hch ultrafine grinding mill, micro powder grinding mill, ultra fine grinding machine

hch ultrafine grinding mill, micro powder grinding mill, ultra fine grinding machine

With yearsaccumulation of experience in R&D, the HCH ultra-fine grinding mill is new ultra fine pulverizing equipment designed by HongCheng. This mill is widely used to grind any non-metallic minerals with Mohs hardness below 7 and moisture below 6%, such astalc,calcite, calciumcarbonate, dolomite,bentonite,kaolin, graphite, carbon black etc.. Product fineness can be adjusted within a range from 325 mesh to 2500mesh and its disposable fineness can reach D97 5um. HCH ultra-fine grinding mill is especially suitable for ultra fine grinding. After a long period of market application practice and user authentication, the device HC1395 model was certified by the China Association of calcium carbonate for energy-saving equipment in China's calcium carbonate ultra-fine processing industry. HCH1395 is the biggest ultra fine circle-roll grinding mill in China.

Technological process: The pre-grinding raw ore material will be crushed into particles10mm and transport to the feeding hopper by the elevator, then feed into the grinding chamber by the feeder. The grinding rollers equip on the rotary table rotates around the centre shaft. There is flexible gap between the roller and ring. The rollers rotate outward by the centrifugal function to compress the fixed ring. The rollers also self- rotates around the roller pin. When material passed through the gap between the ring and roller, the material will be smashed by the rotating rollers. Four layers of rollers. Material will be grinded 1st time when passing the 1st layer of roller and ring. Then be grinded second, third and fourth time when loop through each layer rollers. Thus the materials were grinded sufficient and obtain much fine powder. The powder fallen down onto the bottom table by gravity will goes up to the classifier for separation by the airflow from blower. The qualified fineness passing from the classifier will be collected by the pulse bag collector as final product, while unqualified fallen down for regrinding till passing through. The powder goes with air flow into the pulse bag filter and collects by the discharging valve.The wind path is in circulation and the airflow is in negative pressure. There will be no dust escape, so the equipment can ensure a no dust operation in workshop.

HCH Ultra-fineGrinding Mill is widely used to grind any non-metallic minerals with Mohs hardness below 7 and moisture below 6%, such as talc, calcite, calcium carbonate, dolomite, bentonite, kaolin, graphite, carbon black etc.. This kind of mill is especially suitable for ultra finegrinding. The fineness can be adjusted from 0.045mm(325 mesh) to 0.005mm(2500 mesh), whose range is much wider than that of traditional RaymondMill.

Higher production capacity and lower power consumption:Non metallic mineral particles feed which feedingsize is less than 10mm, canbeone-time processedas < 10 m powder (97% passing). The particlesize less than 3um accounted for about 40%,which contributes to a largerspecific surface area.It has the advantages of low cost,high efficiency, andgoodproduct fineness.

Wide fineness and flexible adjustment: Turbine classifier (patent no.: ZL201030143470.6). The fineness can be adjusted flexibly from 0.04mm (400 mesh) to 0.005mm (2500 mesh). Products with various fineness can meet the market needs and improve your competitiveness.

Environmental protection: The pulse collecting system will remove 99.9% of the dust, ensuring dust-free operation environment. The pulse dust collection system is Hongcheng special invent comply for the environment protection requirements.

Thorough CleaningThe pulse dust collection system is adopted with pulse-jet type of cleaning. By utilize the compression air to shoot clean each filtering bag. High and complete dust cleaning. Prevent bags from powder stocking.

Simply complete the form below, click submit, you will get the price list and a Hongcheng representative will contact you within one business day. Please also feel free to contact us by email or phone. ( * Denotes a required field).

Copyright 2004-2018 by Guilin Hongcheng Mining Equipment Manufacture Co. LTD All rights reserved Tel: |FAX: | E-mail: [email protected] | After-Sales-Service:+86-400-677-6963.

minerals engineering conferences - ultrafine grinding 06

minerals engineering conferences - ultrafine grinding 06

What is ultrafine grinding and what role can ultrafine grinding play in the minerals industry now or in the future? This theme attracted representatives from equipment manufacturers, suppliers of grinding media, mining companies, consultants and academics to a conference in the seaside resort of Falmouth in Cornwall, UK (12-13th June 2006). The conference was attended by 64 delegates from 24 countries spread across all five continents.

While the concept of grinding minerals hardly requires an introduction, it emerged that the definition of ultrafine particles depends on the application: it can relate both to particles in the low m size range and to particles which have been considerably reduced in size. Traditional barriers to ultrafine grinding are the relatively high energy requirement and a perceived reduction in efficiency during further processing. However, technological advances in ultrafine grinding may be welcomed by the mining sector, where the necessity to process increasingly complex ores is presently coupled to buoyant commodity prices.

While conventional milling techniques may produce an ultrafine grind, the required energy rises sharply as the product size, often characterized in terms of the 80 % passing size, d80, decreases. Ultrafine grinding techniques are those techniques which are more energy-efficient than conventional milling techniques in the sub 100 m range. Other advantages over conventional techniques are the option to avoid contamination of the product with ferrous chips, for example from steel balls used as grinding media, lower wear for ultrafine applications, the ability to contain dust and manage heat generation. On the downside, D. Yan states that ultrafine grinding techniques are less predictable than conventional ball mills in terms of energy requirement and grinding performance while throughput may be limited.

During ultrafine grinding, particle breakage occurs by familiar mechanisms: impact or attrition by shear or a combination of these. Classic examples of impact techniques are jetmills where particles are either accelerated against a surface or against other particles moving in the opposite direction. While impact techniques are not suitable for breaking relatively tough materials such as quartz, modified jetmills may be useful for some tough applications. J. Roth (PMT-Jetmill) presented the spiral jetmill as an alternative to classic jetmill designs. The feed is injected into the milling chamber through tangential nozzles while the product is recovered through the classifier rotor located in the middle of the milling chamber. Intense shear between the particles in the milling chamber can produce delamination, preserving or even increasing the aspect ratio of particles. This is beneficial, for example, when talc is ground to enable separation of quartz prior to its application as a reinforcing filler in plastics. In another example, B.G. Kim added that it is attractive to preserve the flaky shape of graphite particles during ultrafine grinding in view of their high conductance.

A. Mc Veigh (Hicom International) discussed application of the Hicom mill for enhancing the recovery of kaolin from china clay waste minerals (silica and mica). Kaolin is commonly used a filler in paper, with platy kaolin enabling the production of lighter and smoother paper. In the Hicom mill, grinding is induced by the inability of the feed to follow the nutating motion of the milling chamber. Product particles escape through openings in the grinding chamber. The Hicom mill can be operated with or without the addition of grinding media. Using relatively fine grinding media, the Hicom mill achieved better delamination than a sand mill currently used by a china clay producer.

Evidence of high-intensity grinding in a Hicom mill was also observed by M. Thornhill, who ground potassium feldspar concentrates with a view to increasing the availability of potassium and assessing their potential as a fertilizer. Trials suggested that ultrafine grinding irreversibly increased the leachability of potassium, although a lower limit to the particle size was observed: very fine particles tended to agglomerate, reducing the specific surface area and the associated leachability of potassium. Comparison with ultrafine grinding of a potassium-rich nepheline syenite concentrate suggest that the effect of mechanical activation achieved by ultrafine grinding is mineral-specific. Although mechanical activation is a difficult concept, E. van der Ven pointed out that ultrafine metal powders can be hazardous on account of their extreme reactivity.

A. Mizitov (Oy Microworld) described the grinding action in a uniRim mill as the equivalent of a pestle-and-mortar. Grinding in the uniRim occurs between the cooled mantle of the grinding vessel and grinding blocks attached to a central rotor. Grinding also occurs well away from the rotor in a planetary mill, which consists of independently-rotating canisters located at the end of arms extending from a central rotor. The combination of centrifugal acceleration of particles towards the rim of the canisters and the even higher angular velocity of the canisters creates a high-intensity grinding environment. E. Kuznetzov (Cyclotec) provided a video to suggest that previous issues such as heat and dust generation, mechanical integrity and discontinuous discharge had been resolved. Scale-up to 100 t/hr is expected to be feasible.

M.K. Abd El-Rahman (CMRDI) studied ultrafine grinding of a variety of minerals in a planetary mill as a function of the rotation speed of the canisters and the presence and size of grinding media in the canister. The advantage of higher rotation speed levelled off at higher speeds, possibly due to cake formation on the canister mantle, while degradation of grinding media increased. Relatively fine grinding media initially led to reduced particle size reduction but, for prolonged grinding, enabled attainment of a smaller product size. This is thought to be due to the smaller interstitial space between media particles, which are generally much larger than the size of product particles. Perhaps surprisingly, a relatively low grinding media-to-feed ratio appeared to increase the initial rate of particle size reduction. For further improvement of grinding performance, the use of chemical additives acting as dispersants was deemed promising.

While stirred media mills stem from a fairly basic design, they have been subject to extensive further development and refinement. For example, the MaxxMill developed by Maschinenfabrik Gustav Eirich consists of a vertical rotating vessel which contains one or more eccentrically-positioned rotors and flow deflectors. Because the MaxxMill operates in dry mode, the smallest particles can be sucked out and classified in an auxilliary cyclone. Particles above a maximum tolerated size are returned to the mill, enabling control of the product size. S. Gerl (Gustav Eirich) presented options to integrate the MaxxMill into processes.

Maelgwyn Minerals Services' M. Battersby introduced the Deswik Turbomicronizer (TM) Mill, a high-speed stirred media mill with a series of impellers along the central shaft. Having evolved from a horizontal design, the vertical Deswik TM Mill is less sensitive to failures of bearing seals and blocking of screens. Feed material is introduced as a slurry at the bottom of the mill, moving upwards in a helix-type flow pattern along a hard-wearing polyurethane resin mill lining. Grinding media are recycled internally to the base of the mill.

Given the technological advances, the focus is turning on the reliability and availability of ultrafine grinding technology in a mining environment. Stirred media mills are starting to feature in large-scale commercial mining applications. Following K. Barns' introduction of the five key process technologies marketed by Xstrata Technology, the application of IsaMill for ultrafine grinding was discussed by D. Curry. Lead/zinc ore at the Mc Arthur River mine in Northern Territories, Australia, requires grinding the ore to below 7 ?m in order to achieve sufficient liberation of galena and sphalerite. Compared to conventional grinding, ultrafine grinding was reported to increase the zinc recovery by 10 %. The IsaMill, which has been developed in partnership with Netzsch Feinmahltechnik, is a high-intensity (up to 300 kW/m3) horizontal disk mill with 8 grinding chambers in series. While media are present to enhance the grinding process, media is retained in the mill without the use of screens. The product is reported to have a narrow particle size distribution, which is considered to be a key factor in maintaining efficient downstream flotation. Using d80 as a parameter, IsaMill may be scaled up, as witnessed by a 3 MW unit being commissioned for AngloPlatinum at Potgietersrust, South Africa.

Anglo Platinum already operates a 2.6 MW unit at Rustenburg, South Africa, for tailings re-treatment, aiming to recover Platinum Group Metals (PGM). C. Rule (Anglo Platinum) explained that ultimate recovery of PGMs locked up in silicates depends on enhanced liberation brought about by ultrafine grinding. A notable improvement in PGM recovery is observed when grinding more tailings below 75 ?m. Anglo Platimum's experience with IsaMill suggests that the wear of mill lining and media consumption were lower than predicted for this application and that the product size distribution and energy consumption were within specification.

The generally advanced nature of stirred media mills was confirmed by the laboratory-scale investigation of two ultrafine grinding techniques by J. Parry. Aiming to liberate fine galena in coarse sphalerite present in ore from Red Dog mine, both the IsaMill and the Stirred Media Detritor (from Metso Minerals) achieved comparable results, as measured with the Mineral Liberation Analyser (from JKTech).

Besides developments in the design and scale-up of stirred media mills, a significant technological breakthrough was achieved with the introduction of a new class of grinding media. Previously, typical grinding media, such as the ore itself, slag, silica sand or river pebbles, suffered from lack of quality, notably inconsistent size and competence. According to P. Hassall (St Gobain-Zirpro), the advent of manufactured media lead to substantial improvement of the media quality through a uniform chemical composition and a high hardness, sphericity, roundness, density, and competency. As a result, the grinding efficiency increases and the energy consumption is lowered. The modern media are typically manufactured ceramic materials such as aluminium oxide, yttrium-, cerium- and magnesium-zirconia oxides and various silicates. B. Clermont (Magotteaux International) described that Keramax MT1 media, containing a mixture of oxides, lowered the energy consumption because there was less sliding friction between hard, spherical media particles. G.A. Graves (Zircoa) emphasised that the smooth surface of media particles, a narrow media size distribution, a high hardness and fracture toughness are vital to achieve energy consumption reduction. Image analysis may be used to monitor the shape and size of media particles. It should be noted that determination of the optimum size of media particles for a given application requires careful consideration. While an application may require media with various media particle sizes, there may be a case for staged milling and ultrafine grinding with optimized media sizes.

While ultrafine grinding can improve recovery and reduce downstream reagent requirements, the effect of extra particle size reduction should be balanced by the cost of additional grinding energy. For example, the Deswik TM Mill reduced a feed with d90 of 89 m to 20 m with 10 kWh/t or 12 m with 16 kWh/t. Ultimately, the economics will decide whether the application of ultrafine grinding will continue to grow.

vertical agitated wet media mill

vertical agitated wet media mill

The agitated media mill ANR from Hosokawa Alpine is designed for the cost-efficient ultrafine grinding of highly concentrated limestone slurries. The operating mode and the design permit the production of extremely high qualities with regard to fineness, degree of whiteness, and abrasiveness.

The mill design ensures low-maintenance continuous system operation with no expensive downtime periods. The flow pattern goes from bottom to top, whereby the feed material is ground to the required end fineness with the aid of ceramic grinding beads (zirconium silicate or zirconium oxide).

hlmx superfine grinding mill

hlmx superfine grinding mill

The traditional ultra-finepowder-processing equipment,due to its low production capacity, is unable to meet the requirements of large-scale productionto satisfythe increasinggreat market demand. Combining several decades of powder mill R&D and production experienceand by introducing advanced technology from Taiwan and Germany, Honecheng has designed and developed the HLMX Superfine Vertical Millbased onHLM Vertical Mill. It becomesthe first choice for large-scale production of ultrafine powderby solving the issue of low production capacity of traditionalsuperfine mill.

The HLMX Superfine Vertical Mill, with static and dynamic separator, can produce powder with a fineness ranging from 325mesh(40m)to 2500 mesh(5m). It can be widely used in chemical, metallurgy, non-metallic mining industries forgrindinglimestone,calcite, marble, calcium carbonate, kaolin, barite,bentonite, pyrophyllite etc. HLMX Superfine Vertical Mill iscapable of providing high qulity filers and additives used in the papermaking, segments, plastic, rubber, pigment,printing ink, PVC and so on.

The motor drives the reducer to rotate the millstone, the raw material issent into the center of the millstone from the air lock rotary feeder. Under the effect of centrifugal force, the material moves to the edge of the millstone. Material than be ground by the force of the roller and smashed under extrusion, grinding and cutting. At the same time, air is blew up around the millstone and bring up the ground material. The air will blow the coarse material back to the millstone. The fine powder will be brought to the classifier, and then, the qualified fine powder will flow out the mill and be collected by dust collector, other coarse powder will be brought down to the millstone by the blade of classifier and be ground again. The circulation like this is the overall process of grinding.

When moving together with the materials to the fridge of the grinding plate, due to its weight, the tramp iron cannot be raised by air flow but falls into the lower mill chamber and then is scraped into the slage outlet to be dischargedby the scraping plate. This efficiently ensures the quality of finished powder product.

With scientific & reasonable design and abovementioned unique advantages, HLMX ultra-fine vertical mills are applied widely in metallurgical, chemical and non-metallic industry, for grinding of various materials, such as limestone, gypsum, coal, barite, calcite etc. Itis large-scale equipment breaking through the bottleneck of ultrafine powder processing capacity. It is your best choice for large-scale production of ultrafine powder.

The secondary classifying system includes ultrafine classifier, fan, dust collector, hopper, screw conveyor and pipes. Ultrafine classifier is the core equipment of the whole system. HLMX series ultrafine vertical mill is equipped with the secondary classifier system, which is capable of efficiently separating coarse powder from fine powder to obtain products of various fineness from 800 mesh to 2000 mesh.

The classifying system is capable of selecting fine particles from the materials. The fineness can range from 800 mesh to 2000 mesh. With the secondary classifying system, different particles size can be obtained and it is also rapid to achieve high production stability product of the same particle size.

(1) The grinding curves of the roller shell and liner plate are uniquely designed based on the ultrafine powder pulverization. The material bed can be formed easily so as to increase the grinding efficiency and the ratio of the finished powder product from the primary grinding.

(3) Adopting the principle of muti-rotor classifier, the product fineness can be easily and efficiently adjustedamong the selected fineness range. HLMX series ultrafine vertical mill saves energy by 30%-50% compared to a common type ultrafine mill when producing the powder of the same fineness.

(1) Combination of crushing, drying, grinding and conveying, simple process flow, reasonable and compact layout, space-saving (50% less than ball mill), lower foundation cost and workshop cost in the field.

(1) The materials bed pulverization principle reduces the duration of the materials retention in the mill and the repeated grinding, which is easy for the powder fineness and components analysis.Moreover, there is less tramp iron in the end powder product, increasing the whiteness and purity of the end powder product.

(3) During the grinding, adding a small amount of additive that will not adversely affect the quality of finished powder product is capable of remarkableimproving the added value of the finished powder product.

(1)Themechanical limit device for the roller is capable of being adjusted so as to ensure the safety clearance between the roller shell and the liner plate on the grinding plate. This effectively removes the possibility of the materials feeding interruptionthus fierce vibration and destructive impact and maintains the safe an economical operation of the mill.

(3)Vertical mill is the better equipment to lower power consumption in the mill industry, which is also what the country advocate and a must to increase the enterprise competitiveness in China powder industry.

lum ultrafine vertical roller mill

lum ultrafine vertical roller mill

(1)Roller can be pulled outside the machine by hydraulic device, large space for replacing the roller liner and repairing the mill,maintenance is very convenient. (2) Roller sleeve can be double sides used , extend the wear-resistant material's life.

The balanced energy storage device can improve rigidity of equipment.While ensuring that the equipment runs in high efficiency,it can effectively reduce equipment's amplitude,stable and reliable in performance;in fine powder or superfine powder production,it shows more advantages.

The unique "sphere upper support structure" changes the roller assembly from cross arm shaft dangling structure to vertical shaft horizontal pendulum structure to realize long-term safe operation.

vxpmill for fine & ultra fine grinding | flsmidth

vxpmill for fine & ultra fine grinding | flsmidth

Ease of implementation and setup are top of mind as you strive to keep your plant running at peak levels of productivity. Our VXPmills are designed for easy shipment, simple installation and trouble-free maintenance. Most importantly, the mills are customisable to each unique mining application, optimising the performance of your mill and increasing ore recoveries. VXPmills are delivered with short lead times at market-leading capital and operating costs.

The VXPmill is a vertically oriented stirred media mill that is open to the atmosphere. They are designed with a modular impeller that has removable discs and spacers. Slurry enters at the bottom, travels upward through the mill chamber, and overflows through a media retention screen at the top. The rotating polyurethane discs activate inert ceramic grinding media inside the milling chamber. This activation fluidises the media bed which performs an attrition grind on the particles in the slurry.

The mills are designed to run at tip speeds between 10 and 15 m/s and are capable of operating with very dense grinding media. The result is a power intensity that is higher than the low-speed mills and overlaps that of the high-speed mills.

There is a large gap between the tip speed and power intensity of the low-speed vertical mills and the high-speed horizontal mills. The VXP mill bridges the gap between high-speed and low-speed mills.

The VXPmills are designed for fine and ultra fine grinding applications. In practice, the mill performs best when the feed has a normal distribution. However, the mill has been used to preferentially grind the coarser hump in bimodal distributions without over grinding the finer part of the distribution.

Grinding efficiency is affected by a wide range of variables. Process parameters such as, slurry flow rate, slurry density, and slurry rheology all affect grinding performance. These variables can often be regulated to fall within an acceptable design range. The mill configuration and/or operating conditions can then be modified to increase the grinding efficiency.

The mills are manufactured in a range of sizes to accommodate different feed rates and process conditions. The laboratory models are generally used for metallurgical and material testing. The pilot mills are designed as modular systems for use on site in pilot trials. These are generally replaced by the larger production mills once pilot trials have been completed.

The VXPmills unique design allows operators to quickly flush and drain the media out of the mill into a holding tank in preparation for disc maintenance. After the flushing cycle is completed, a valve is simply opened at the bottom of the mill and the ceramic beads drain into a temporary media storage tank.

FLSmidth provides sustainable productivity to the global mining and cement industries. We deliver market-leading engineering, equipment and service solutions that enable our customers to improve performance, drive down costs and reduce environmental impact. Our operations span the globe and we are close to 10,200 employees, present in more than 60 countries. In 2020, FLSmidth generated revenue of DKK 16.4 billion. MissionZero is our sustainability ambition towards zero emissions in mining and cement by 2030.

in-depth analysis of ultrafine mill manufacturers and its prices fluctuation

in-depth analysis of ultrafine mill manufacturers and its prices fluctuation

Crushing effect and production efficiency hae a direct impact on the further development of downstream industries,in order to standardize the operational process, and ensure the grinding fineness and the capacity of the ultrafine mill, we interviewed a great number or ultrafine mill manufacturers and made a summary about the interview.

I. straining force on the hydraulic device . According to the analysis conducted by the ultrafine mill manufacturer, the straining force matters so much for the crushing effects. The stronger the straining force gets , the more pressure it will exert on the raw material, the greater fineness of the final products will be. But please pay special attention to the brittle materials, too much staining force can cause the vibration of the ultrafine mill which will increase the energy consumption.

II. Raw material thickness.Unlike traditional crushing and grinding methods, ultrafine mill is designed in light of the thickness of the raw material. The details of the ultrafine mill can be found in the special report of the ultrafine mill.The pressure on the raw material made by roller and rotate medium diameter has been calculated accurately. Driven by the centrifuge force,high-speed disc can separate the qualified powder into the classifier. With the fixed straining force, by setting the reasonable thickness of the raw material, much more qualified powder can be produced.

III. Roller and disc. As the wear parts of the ultrafine mill, roller and disc can get damaged during the process of the production. Therefore, it will be necessary to fix and replace them timely. Once the squeeze surface appears uneven, the final products will be in different sizes,including lots of coarse aggregate. The price of ultrafine mill is closely related with its performance. It will be essential for buyers to make a budget on the quality and lifespan of the wear parts.

IV. Raw material. In terms of raw material, it will save lots of energy to process those brittle materials. As it will be taken seriously on the fineness and its shape. Manufacturers recommend to choose the model of the ultrafine mill in accordance with the raw material and its capacity. The practical effects of one certain mill vary for different raw materials.

manufacture to mine - manufacture to mine | isamill

manufacture to mine - manufacture to mine | isamill

Conventional Ball and Tower Milling were not economic to grind below 25 microns, due to low energy efficiency, low power intensity and high media consumption. Further, the high steel media consumption in these mills was severely detrimental to flotation performance.

Investigations into fine-grinding started at Mount Isa started in the 1970s using conventional grinding technology to increase mineral liberation by grinding to fine sizes. These technologies were not only found to have high power consumption but also proved to be detrimental to flotation performance as a result of pulp chemistry and iron contamination from steel media. These poor results were revisited during pilot plant and tower mill testwork in the 1980s which also showed an inability of tower mills to economically achieve the required sizes.

It was clear that the solution to efficient fine-grinding did not exist in the minerals industry. So we looked for ideas to "crossover" from other industries that also ground fine particles pigments, pharmaceuticals, foodstuffs (e.g. chocolate). While these mills operated at a much lower scale and treated high value products they demonstrated the principle that stirring fine media at high speed was highly efficient. Perhaps the concepts could be developed to treat large tonnages of lower value materials?

In 1991 the introduction of a Netzsch laboratory stirred mill to the Mount Isa site was a turning point in fine-grinding and ultrafine grinding. The litre bench scale mill resembled a milk shake maker and used fine copper smelter slag as grinding media. Testwork on McArthur River ore started in 1991, and by January 1992, a small pilot scale mill, LME100, had been designed and installed at the Mount Isa pilot plant. The testwork showed that high speed, inert, horizontal mills could efficiently grind to 7 microns at laboratory scale providing major improvements in metallurgical performance. To make ultrafine grinding applicable to full-scale production a program of development was undertaken between Mount Isa Mines Limited and NETZSCH-Feinmahltechnik GmbH.

After 7 years of development and testing of prototypes in the Mount Isa operations, the IsaMill evolved. It was large scale, continuous, and most importantly robust because it was developed by operators. The crucial breakthrough was the perfection of the internal product separator this allowed the mill to use cheap natural media (sand, smelter slag, ore particles) and to operate in open circuit. These are significant advantages for operating cost and circuit simplicity. Scale-up was tested using trial installations at the Hilton and Mount Isa lead/zinc concentrators. By the end of 1994, the first full scale IsaMill (1.1MW) was installed in the Mount Isa concentrator.

In 1998 the rights for commercialisation of the IsaMill where transferred from Mount Isa Mines Limited to MIM Process Technologies (now Glencore Technology) and under an exclusive agreement with Netzsch. In December 1998, the IsaMill technology was launched to the metalliferous industry as a cost effective means of grinding down to and below 10 microns.

Moving stirred milling "from ink to zinc"was the hard part. The next challenge was to apply the same energy and processing advantages to mainstream grinding. This needed two further developments an even bigger mill and low-cost, competent ceramic media. The first M10,000 IsaMill was installed in South Africa in 2003, and Magotteaux developed KERAMAX MT1 ceramic media specifically for IsaMilling in 2005.

Since then, the 3MW M10,000 has become the most commonly installed IsaMill. The power installed in regrind and coarse grinding applications has quickly outstripped that used in ultra fine grinding. This remarkably rapid adoption in coarse grinding reflects the robustness and simplicity of IsaMill technology.

In just 11 years since the first IsaMill was installed at the Hilton Concentrator, IsaMills increased their capacity 16 fold from 205kW to 3MW and their volume has increased 20 times. This rapid increase in capacity can be compared to autogenous milling technology which although available since 1907 took 19 years (from 1940 to 1959) to increase power draw by just 6. (from Burford Fine Grinding and Project enhancement, Innovative Mineral Developments AUSIMM 2004)

By the end of 2010 there will be 81 IsaMills operating with over 130MW of installed power. Feed sizes are as coarse as F80 of 250m. The product sizes ore as low as P80 of 7m for materials ranging from lead and zinc sulphides, platinum concentrates, industrial minerals, iron oxide and refractory gold concentrate. Such a new technology has been embraced by those operations that rely on grinding to achieve metal recovery.

higmill high intensity grinding mill - metso outotec

higmill high intensity grinding mill - metso outotec

The Metso Outotec HIGmill is an advanced, energy-efficient fine and ultra-fine grinding solution that utilizes proven technology. With the tall, narrow, vertical body arrangement, grinding media is evenly distributed and mineral particles remain in constant contact, significantly increasing grinding efficiency. It takes advantage of gravitational forces and GrindForce rotor technology to produce a finer grind for mineral liberation.

The HIGmill comprises a mill body, shaft with grinding discs, shell mounted counter rings, gearbox, and drive. The grinding chamber is filled up to 70% with grinding beads. Rotating discs stir the charge and grinding takes place between beads by attrition. The number of discs (grinding stages) depends on the application and can be as high as 20. Feed slurry is pumped into the mill via the bottom connection. When the flow transfers upwards, it passes all consecutive grinding stages. The final product discharges into open atmosphere at the top of the machine.

Gravity keeps the media compact during operation to ensure high intensity inter-bead contact, as well as efficient, even energy transfer throughout the volume. The disc configuration and the whole chamber geometry have been optimized for efficient energy transfer to the bead mass, internal circulation, and classification.

The Metso Outotec HIGmill comes in various drum diameters. The mill heights can be varied to optimize the media load and power input for specific applications. Chamber volumes range up to 50,000 liters with corresponding drives ranging up to 6,500 kW. The HIGmill is the only ultrafine grinding technology in commercial use that can use small-size high-density grinding media in mill sizes above 3000 kW.

HIGmill offers a unique opportunity to optimize on-line product fineness. The control principle is to measure scalping cyclone feed quantity and adjust the mill shaft speed to reach target energy per total feed flow. Alternatively, particle size distribution is measured by the Outotec PSI on-line particle analyzer and the shaft speed adjusted to maintain constant product size.

HIGmill has a less complex and more compact process layout and flow sheet than other stirred media mills. The process comprises just a scalping cyclone, feed tank and pump, and the mill itself. The benefit of high power intensity and vertical installation is a very small footprint. The head room over the mill is small and the flanged split-shell construction reduces the space needed for maintenance. The top-supported hanging arrangement keeps the floor and sides clear, simplifying maintenance and emptying the beads.

parameter optimization of ultrafine comminution based on analytic hierarchy process: fuzzy comprehensive evaluation

parameter optimization of ultrafine comminution based on analytic hierarchy process: fuzzy comprehensive evaluation

Zaisheng Zhu, Jinbo Zhu, Yin Liu, Huaizhi Shao, Hongzheng Zhu, Chuanzhen Wang, Jingyu Wang, Yang Fan, "Parameter Optimization of Ultrafine Comminution Based on Analytic Hierarchy Process: Fuzzy Comprehensive Evaluation", Journal of Control Science and Engineering, vol. 2021, Article ID 6642402, 7 pages, 2021. https://doi.org/10.1155/2021/6642402

This paper proposes a fuzzy comprehensive evaluation of ultrafine powders, namely, yield and quality value-based feature selection. Three indicators reflecting product yield and quality were selected to construct a simple and practical fuzzy comprehensive evaluation protocol. The weight set of the indices and the fuzzy evaluation set were calculated based on the analytic hierarchy process (AHP) method. The fuzzy comprehensive evaluation value was worked out as the only comprehensive index for the evaluation of product. The best ultrafine comminution condition will be established through the comparison of the fuzzy comprehensive evaluation values. Single-factor experiments and orthogonal experiments of the main influencing factors of ultrafine comminution were conducted. It was concluded that the importance of each factor is sequentially the concentration, specific surface area (SSA) of the media, and percentage of critical speed (PCS). Moreover, the concentration and SSA of the media were equally important. Ultrafine comminution by ball mill had the best overall performance under the PCS of 85%, the SSA of the media of 0.24m2/kg, and the concentration of 75%.

Grinding has been utilized in manufacturing fine and ultrafine powders for the development of new materials and for improving product quality [1, 2]. The grinding technology can significantly affect the particle characteristics [3], but not a single-objective process [4]. It is difficult to pulverize the particles directly to required particle size, which generally includes pulverization and classification or prepulverization and ultrafine pulverization [5]. The grinding optimization has been studied in the fields of cement production, chemical industry, metallurgical fine grinding, mineral grinding, and other industries [6, 7]. It can be seen that the proportion of the grinding cost is a large part [8, 9]. Therefore, the study on grinding optimization is valuable and significant, so as to make the equipment have a better grinding response.

In order to solve the problem of multiobjective optimization, many scholars have established comprehensive evaluation criteria or methods, such as power coefficient measurement method, constraint method, and failure mode and effect analysis (FMEA) method [10, 11]. The optimization of the mineral ultrafine grinding process is a multiobjective optimization problem [4, 12]. In many cases, the unit of measurement of each index is different. Therefore, it is difficult to objectively evaluate whether the optimized multiobjective problem is good or not.

Fuzzy set theory, introduced by Zadeh [13], resembles human reasoning in its use of approximate information and uncertainty to generate decisions. It was specifically designed to provide formalized tools for dealing with the imprecision intrinsic to many problems [14]. The fuzzy comprehensive evaluation method has been well applied in many fields [15, 16]; however, it is less involved in the field of mineral crushing. In this study, the fuzzy comprehensive evaluation system, which is based on the analytic hierarchy process, was introduced into the field of ultrafine grinding; comprehensive indicators were used to optimize the ultrafine grinding process of mineral powders. The study aimed at optimizing the three main factors (the mass of powders smaller than 10m , the fractal dimension of particle size distribution and d97) affecting the ultrafine grinding of mineral powders.

Potassium feldspar powders were used in this study, which were collected in Jiangsu Province. The d97 of sample was 63.68m, and the particle size of smaller than 10m was about 35.32%, which was measured by a laser particle size analyzer (Model: BT-9300H). Sodium polyacrylate dispersant was purchased from the Chengxin Chemical Material Supply Station in Zhejiang Province.

The samples were ground in a steel tank ball mill using the wet ultrafine pulverization method, by the ball grinder, with the rated power of 1000W and the critical speed of 85rpm. The ceramic tank with the inner diameter of 250mm, the inner height of 275mm, and the volume of 13.5L were used. Two kinds of steel balls with the sizes of 12mm and 17mm were used in this experiment. Refer to previous research experiments [17]; the mass of ore powders was fixed at 3.66kg at a slurrys mass concentration of 55% and the amount of dispersant was of 0.2% of the mineral powder weight. The specific surface area of the grinding media that consists of 6.6kg of 12mm steel balls and 28kg of 17mm steel balls was 0.20m2/kg. The operational percentage of critical speed was 95%. The relevant data of the product ultrafine pulverized after 3h were analyzed. A single-factor experiment was designed to analyze the main influence factors of the ball mill (rotation rate, SSA of the media, and concentration) in turn, and then the orthogonal experiments were designed to find the optimal process conditions.

Three indicators reflecting product quantity and quality were selected to construct a simple and practical fuzzy comprehensive evaluation scheme for ultrafine powders. The mass of powders smaller than 10m (m10) was used to measure the yield. The fractal dimension of particle size distribution (PSD) and d97 were chosen to measure the quality of the production.

The analytic hierarchy process established by Saaty [18] is a decision-making method combined qualitatively and quantitatively [19, 20]. The function f(x, y) indicates how important the indicator x is compared to the indicator y; the function f(y, x) indicates how important the indicator y is compared to the indicator x. The values of f(x, y) and f(y, x) can be defined according to subjective judgment. If x is as important as y, f(x, y)=1; if x is especially more important than y, f(x, y)=9, and so on. f(x, y)[1, 9]; f(y, x)[1/9, 1].

If CR0.1, it can be acceptable. When potential conflict emerges in evaluation [21], the CR is unacceptable and the decision-maker is encouraged to repeat the pairwise comparisons, or some approaches should be adopted to process highly conflicting data [22, 23].

According to the AHP theory, the weight vector is calculated using the power method, sum method, root method, and the characteristic roots method, among which the sum method is the simplest. In the case where the judgment matrix is consistent, each calculation method can obtain an accurate solution. The sum method was selected to calculate the weight vector in this study. The weight of each indicator is obtained through related calculation formulas. The weight of m10 (1) is 0.69, the weight of D (2) is 0.149, and the weight of d97 (3) is 0.161, so the weight vector can be represented as =(0.69, 0.149, 0.161)T.

The degree of membership 1 of index m10 value was calculated by membership function f(m10), degree of membership 2 of index D value calculated by membership function f(D), and degree of membership 3 of index d97 value calculated by membership function f(d97), respectively. The membership functions f(m10), f(D), and f(d97) are constructed in Section 3.1.1. The weight of m10 (1), the weight of D (2), and the weight of d97 (3) was calculated according to the AHP theory.

The initial experiment conditions were set first. The ore powder slurry was prepared at 55% solid concentration by mass. SSA of the grinding media was 0.20m2/kg. The additive amount of dispersant was 0.2% of mineral powder. The PCS of the tank was 95%. The result shows that m10=2.656kg, D=2.225. According to PSD curve calculation, it can be calculated that d97=25.36m. Therefore, the evaluation set U=(m10, D, d97)=(2.656, 2.225, 25.36).

In the raw material, m10 was 1.293kg. And, the total mass of the raw material was 3.66kg, so the value range of the mass m10[1.293, 3.66]. From geometric knowledge [26], the range of D[1, 3].

Ideally, when all raw mineral powders are pulverized to 10m, d100 was 10m and d97 was less than 10m. In this study, d97 could be approximated as d100, and thus d9710m. In the worst case, there were no fresh 10m powders formed in the product, so the upper limit of d97 was 63.68m. Therefore, d97[10, 63.68].

The kinetic equation [27], which has been revised by Aliavden [28], used to describe the grinding process of materials is obtained as the following equation:where y0 is the initial sieve residue of ground materials with a certain particle size; k is the grinding rate constant; and n is the time index and determined by the property of ground material and its grinding conditions.

With the propelling of the ultrafine pulverization, the difficulty became greater. The second-degree parabolic membership function, which corresponded to pulverization kinetic curve [29], was selected. Because the indicator m10 was a benefit-type indicator, the larger the value, the better the product. While D and d97 were the cost-type indicators, the smaller the value, the better the product. Therefore, the membership functions used for the three indicators were different. The following formulas (equation (6)) are the membership functions of the indicators m10, D, and d97:

The values of indicators were changed into membership degrees , [0, 1]. Take one indicator of them, m10, as an example. In the product, m10=2.656kg, and 1.293<2.656<3.66, so the membership degree of m10 could be obtained by equation (6).

According to equation (7), the multi-indicator fuzzy comprehensive evaluation value Z can be calculated from the fuzzy evaluation set U and weight set of each indicator W., where U=(0.332, 0.15, 0.51) and W=(0.69, 0.149, 0.161)T; therefore, Z=0.334.

The single-factor experiment was designed to find the influence of single factor. Then, the orthogonal experiments were followed to analyze the best process conditions. Taguchi L9 (34) orthogonal arrays were generated by the IBM SPSS Statistics 25.0.

When the experimental PCS was set to 85%, the effect of ultrafine pulverization of mineral powders was best. With a gradual increase in the PCS, the fuzzy comprehensive evaluation value of the experiment results increased rapidly. After the curve reached the highest point, it gradually decreased, but the decrease of Z value was not as rapid as before. When the PCS exceeded 100%, the fuzzy comprehensive evaluation value of the results also dropped rapidly.

With the increase of the PCS, the movement of balls was changed from the principal tumbling form to the combinative impacting form and the tumbling form. The continuous increase of the PCS could cause the media to adhere to the wall, and the force on the particles would reduce. Changes of PCS changed the force distribution (impact force, shear force, frictional force, etc.) [30] between media and powders. The synthetic effect of several forces according to a certain distribution ratio made the possibility of particle refinement increase; thus, the effect was better.

The best parameters of SSA of the media were explored under the conditions where the operational concentration was 55% and the PCS was 85%. The different SSAs of the media were achieved by adjusting the ratio of the two different-sized media. The results are shown in Table 2.

When the SSA of the media was 0.22m2/kg, ultrafine pulverization of mineral powders performs best. Small SSA of the media would greatly reduce the number of point contact among the balls, and the chance of the contact of slurry with grinding balls would be dramatically reduced [31]. During the movement of the media, although the impact force of a single ball on the material was increased, the frictional force and shear force were greatly reduced. The SSA of the media continued to increase, and the fuzzy comprehensive evaluation value of the product did not decrease greatly, which indicates that the impact force was not the main force. The friction force and shear force were the main forces in the pulverization process. In the late stage of ultrafine pulverization, the particles became round and the edges and corners basically disappeared.

When the concentration was 65%, the ultrafine pulverization of mineral powders works best. When the concentration was low, the PSD of product was narrow; however, the yield of product was low. In reverse, the PSD of product was extremely wide; although the yield of product had advantages, there were many large particles in the product, which affected the total quality. If the concentration was low, there were more opportunities for the occurrence of contact between the balls and the particles, but the contact between the particles was insufficient. When the concentration was too high, the liquidity of the slurry reduced sharply and the motion of balls and particles were obstructed, leaving some large particles uncrushed. According to Bed comminution [32], when there were more particles, there were more particle-particle contact; smaller particles would definitely be produced under the same pulverization condition. Therefore, an appropriate increase in the concentration would increase the fuzzy comprehensive evaluation value of the product.

The sequence of the factors influencing the product feature was listed by polar value analysis. With the indicator m-10 as the appraising indicator, maximum differences (R) of each factor were calculated orderly. R (concentration)=0.994, R (PCS)=0.227, R (SSA of the media)=0.330; the factors were ranked in order of importance, and concentration>SSA of the media>PCS. With the indicator D as the appraising indicator, R (concentration)=0.181, R (PCS)=0.130, R (SSA of the media)=0.163, and concentration>SSA of the media>PCS. With the indicator d97 as the appraising indicator, R (concentration)=17.817, R (PCS)=6.343, R (SSA of the media)=5.233, and concentration>PCS>SSA of the media. Obviously, the significance ordering of the factors was contradictory when choosing different appraising indicators. With the indicator Z as the appraising indicator, R (concentration)=0.054, R (PCS)=0.039, and R (SSA of the media)=0.053. Concentration>SSA of the media>PCS; moreover, the concentration and SSA of the media were equally important.

Using the fuzzy comprehensive evaluation value as an indicator, combined with polar value analysis, the optimal process conditions were obtained. The optimal PCS should be at 85%; the optimal SSA of the media should be at 0.24m2/kg and the optimal concentration should be at 75%.

Under the optimal conditions, a verification experiment was conducted to analyze the relevant parameters of the product, and the results are shown as follows: m10=3.415kg, D=2.483, and d97=47.96m. Based on the membership function used in the orthogonal experiments, the membership degrees of each indicator were calculated, 1=0.256, 2=0.067, and 3=0.086. Finally, the maximum fuzzy comprehensive evaluation value under the optimal process parameters was obtained, Z=0.200. Therefore, the optimal operational factors obtained by polar value analysis were correct.

(1) The significance of three indicators of the ultrafine powders is analyzed by the analytic hierarchy process method. (2) According to the three indicators, the fuzzy comprehensive evaluation based on analytic hierarchy process is used to obtain the comprehensive indicator. (3) The three main factors influencing ultrafine comminution, concentration, specific surface area of the media, and percentage of critical speed are significantly ranked by the orthogonal test. The optimal operating conditions have been obtained subsequently.

The authors gratefully acknowledge the financial supports provided by the National Natural Science Foundation of China (51374015); Natural Science Foundation of Anhui Province (2008085QE272); China Postdoctoral Science Foundation (2020M671837, 2019M662134); and Anhui Provincial Excellent Talent Project (gxyqZD2020019); The authors would like to extend their special thanks to Prof. Zhenfu Luo.

Copyright 2021 Zaisheng Zhu et al. This is an open access article distributed under the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited.

lum ultrafine vertical mill

lum ultrafine vertical mill

LUM Series Ultrafine Vertical Grinding Mill is designed on the basis of years of grinding mill production experience. It adopts the Taiwanese grinding roller technology and German powder separating technology. The ultrafine vertical grinding mill integrates ultrafine powder grinding, grading, powder collecting and transporting.

As the dedicated mid-to-high end processing equipment in plastic masterbatches, PVC, artificial stone, electric cable, non-woven fabrics and other industries, LUM Series Ultrafine Vertical Grinding Mill is mainly used for the ultrafine grinding of calcite, marble, limestone, talc, dolomite, barite, kaolin, wollastonite, gypsum, feldspar, pyrophylite and other non-metallic mineral ores.

(4) LUM Ultrafine Vertical Grinding Mill adopts mechanical position-limiting device, so that there is no direct contact point between grinding roller and millstone, which can avoid the destructive impact caused by machine vibration.

(5) Multi-rotor cage-type powder concentrator has high efficiency. Its easy to be adjusted and controlled, which is helpful to achieve the fast switch among different production demands. Therefore, the efficiency of the whole production line can get improved.

The millstone rotates under the action of main motor and reducer. After being weighed on the belt scale, raw materials, along with the elevator, spiral conveyer, star-shaped feeding valve and feed screw, fall on the center of millstone and next they move to the edge of millstone under centrifugal force. While passing through the grinding area between roller and millstone, raw materials will be pulverized by the pressure of roller and the shearing force between roller and millstone. Raw materials after grinding continue moving to the edge of millstone until they are brought into multi-rotor powder concentrator by the airflow of the high-pressure fan. Powders which fail to meet requirement of fineness fall on the millstone for re-grinding while the ones meeting the requirements enter the dust collector along with airflow, and are then transported to product bin by elevator or pneumatic transport system.

The main machine is equipped with high-efficiency multi-rotor powder concentrator, so that the final products can have multiple sizes. Content of 2m of powder can reach as high as 70%. The screen rate of particles whose sizes are within 445m can reach 97%. The specific surface area is around 21000cm^2/g. The discharging rate of 8.5m of powder can reach 97%. Through secondary powder collection, 4-5m of powder can be separated. The particle size distribution of finished powder is narrow, and the content of 2m of powder can be adjusted. And the finished powder has fine shape, making it have high added value.

The optimized roller, millstone and inner airflow guidance design greatly improve the grinding efficiency. The capacity of LUM ultrafine vertical grinding mill is 30% higher than similar products and the power consumption is 30%-60% lower than ball mill.

The internal part adopts PLC automatic control system while the external part adopts touch screen so as to display and adjust the parameters in real time. The reserved modular interface has strong expansibility, which can quickly realize the connection between front-end grinding aid adding system and back-end powder modification system and packaging system, ensuring the automatic control of the whole process.

All the wear-resistant parts of main machine adopt imported wear-resistant material, which effectively prolongs their service life and reduces the iron content in the products and decreases the maintenance costs.

With new structural designs and grinding principle, LUM Series Ultrafine Vertical Grinding Mill has small vibration and low noise. The equipment is sealed as a whole and works under negative pressure. All the dust points are controlled by pulse dust filter, so there is no dust overflow, meeting the national environmental protection requirements.

industrial crushing machine, stone crusher equipment for sale, mineral crusher supplier

industrial crushing machine, stone crusher equipment for sale, mineral crusher supplier

New generation crusher, pew series jaw crusher is born with innovative significance. It is newly designed and improved by our experts on basis of their more than 20 years' crusher manufacturing and design experience. The unique design concept makes this series crusher achieve perfect combination between crushing efficiency and operating cost. Meanwhile, it has a wide range of application, particularly is suitable for crushing hard rock, such as basalt, river pebbles.

ZENITH HPT multiple cylinder hydraulic cone crushers, which incorporates the latest global crushing technologies with high efficiency and easy operation, are the pacemaker in Chinas hydraulic cone crushers for the excellent operating performance and positive customer feedback. It efficiently fulfills various crushing demands, such as: large capacities, first-class cubicity, low operating and maintenance cost, full process adaptability, etc.

HST Series Single Cylinder Hydraulic Cone Crusher is a new and efficient crusher researched and designed autonomously on the base of our twenty years' experience in the crushing industry engaged in design, production, sales and service, combining with the development of modern industrial technology, and drawing advanced crusher technology from the United States, Germany and other countries.

HP series Cone Crusher (Hydraulic) adopts computer optimization design to speed up main shaft speed. The unique crushing chamber replace system can quickly replace components in crushing chamber to meet different size requirement. The friction disc design and rotation of eccentric shaft bushing around fix cone plus more reasonable labyrinth seal system are unique features of HP series, which have more advantages like easier operation, larger application scope, more reliable, more smooth functioning comparing with spring and traditional cone crusher.

For higher productivity, better reliability and flexibility, longer service life, and better final product quality, the S series cone crusher is your best choice absolutely. S series cone crusher offers several outstanding features such as excellent tramp release system, unique hydraulic lifting system, all of these features ensure the S series cone crusher offer the unbeatable performance in secondary, tertiary and quaternary applications.

PFW Series impact crushers are the latest development of impact crusher based on ZENITH's 20 years experience and leading technology in the crushing industry. PFW series impact crusher features heavy duty rotor design, unique hammer locking system, interchangeable wearing parts, and easy maintenance. This series impact crusher provides customers low capital cost solution, outstanding performance, good cubical shape, lowest operation cost per ton, and wide materials application.

Thousands of Zenith PF Series Impact Crushers are installed all over the world in recent 20 years. It has been proved that this series of crushers not only effectively increase productivity and final product quality, but also greatly reduce the investment costs and operation costs. Unmatched excellent performance is shown in the secondary crushing, tertiary crushing and material recovery.

energy use of fine grinding in mineral processing | springerlink

energy use of fine grinding in mineral processing | springerlink

Fine grinding, to P80 sizes as low as 7m, is becoming increasingly important as mines treat ores with smaller liberation sizes. This grinding is typically done using stirred mills such as the Isamill or Stirred Media Detritor. While fine grinding consumes less energy than primary grinding, it can still account for a substantial part of a mills energy budget. Overall energy use and media use are strongly related to stress intensity, as well as to media size and quality. Optimization of grinding media size and quality, as well as of other operational factors, can reduce energy use by a factor of two or more. The stirred mills used to perform fine grinding have additional process benefits, such as polishing the mineral surface, which can enhance recovery.

Fine grinding is becoming an increasingly common unit operation in mineral processing. While fine grinding can liberate ores that would otherwise be considered untreatable, it can entail high costs in terms of energy consumption and media use. These costs can be minimized by performing adequate test work and selecting appropriate operating conditions. This paper reviews fine grinding technology, research, and plant experience and seeks to shed light on ways in which operators can reduce both operating costs and the environmental footprint of their fine grinding circuit.

This paper will begin by giving an overview of fine grinding and the equipment used. It will then discuss energyproduct size relationships and modeling efforts for stirred mills in particular. The paper will go on to cover typical test work requirements, the effect of media size, and the contained energy in media. In closing, specific case studies will be reviewed.

Grinding activities in general (including coarse, intermediate, and fine grinding) account for 0.5pct of U.S. primary energy use, 3.8pct of total U.S. electricity consumption, and 40pct of total U.S. mining industry energy use. Large energy saving opportunities have been identified in grinding in particular.[1]

TableI shows a very large disparity between the theoretical minimum energy used in grinding and the actual energy used. More interestingly, a fairly large difference remains even between Best Practice grinding energy use and current energy use. This suggests that large savings in grinding energy (and associated savings in maintenance, consumables, and capital equipment needed) could be obtained by improving grinding operations.

As fine grinding is typically used on regrind applications, the feed tonnages to fine grinding circuits are small compared to head tonnages, typically 10 to 30tph. However, the specific energies are often much larger than those encountered in intermediate milling and can be as high as 60kWh/t. Total installed power in a fine grinding circuit can range from several hundred kW to several MW; for example, the largest installed Isamill has 3MW installed power.[3] This quantity is small compared to the power used by a semi-autogenous mill and a ball mill in a primary grinding circuit; a ball mill can have an installed power of up to 15MW, while installed power for a SAG mill can go up to 25MW. However, the energy used for fine grinding is still significant. Moreover, as this paper seeks to demonstrate, large energy reduction opportunities are frequently found in fine grinding.

Grinding can be classified into coarse, intermediate, and fine grinding processes. These differ in the equipment used, the product sizes attained, and the comminution mechanisms used. The boundaries between these size classes must always be drawn somewhat arbitrarily; for this paper, the boundaries are as given in TableII. As shown in the table, coarse grinding typically corresponds to using an AG or SAG mill, intermediate grinding to a ball mill or tower mill, and fine grinding to a stirred mill such as an Isamill or Stirred Media Detritor (SMD). Of course, various exceptions to these typical values can be found.

In fine grinding, a material with an F80 of less than 100m is comminuted to a P80 of 7 to 30m. (P80s of 2m are at least claimed by equipment manufacturers.) The feed is typically a flotation concentrate, which is reground to liberate fine particles of the value mineral.

The three modes of particle breakage are impact; abrasion, in which two particles shear against each other; and attrition, in which a small particle is sheared between two larger particles or media moving at different velocities. In fine grinding, breakage is dominated by attrition alone.[4] In stirred mills, this is accomplished by creating a gradient in the angular velocity of the grinding media along the mills radius.

Fine grinding is usually performed in high-intensity stirred mills; several manufacturers of these stirred mills exist. Two frequently used stirred mills include the Isamill, produced by Xstrata Technology, and the SMD, produced by Metso (Figure1). A third mill, the KnelsonDeswik mill (now the FLS stirred mill), is a relative newcomer to the stirred milling scene, having been developed through the 1990s and the early 2000s.[5] In all these mills, a bed of ceramic or sand is stirred at high speed. Ceramic media sizes in use range from 1 to 6.5mm.

The Isamill and the SMD have very similar grinding performance. Grinding the same feed using the same media, Nesset et al.[7] found that the Isamill and SMD had very similar specific energy use. Gao et al.[8] observed that an Isamill and SMD, grinding the same feed with the same media, produced very similar product particle size distributions (PSDs). This similarity in performance has also been observed in other operations.

Nevertheless, there are important differences. In the Isamill, the shaft is horizontal and the media are stirred by disks, while in the SMD, the stirring is performed by pins mounted on a vertical shaft. In an SMD, the product is separated from the media by a screen; the Isamill uses an internal centrifugation system. This means that the screens in an SMD constitute a wear part that must be replaced, while for the Isamill, the seals between the shaft and body constitute important wear parts. Liner changes and other maintenance are claimed by Xstrata Technology to be much easier than in an SMD: While an SMDs liner is removed in eight parts, the Isamills liner can be removed in two pieces, with the shell sliding off easily.[3] The KnelsonDeswik mill is top stirred and can therefore be considered to be similar to an SMD.[5]

An important difference among the Isamill, the SMD, and the KnelsonDeswik mill is that of scale. The largest Isamill installed at time of writing had 3MW of installed power; an 8MW Isamill is available, but appears not to have yet been installed.[3] The largest SMD available has 1.1MW of installed power; one 1.1-MW SMD has been installed. The next largest size SMD has 355kW of installed power.[6] Thus, several SMDs are often installed for a fine grinding circuit, while the same duty would be performed by a single Isamill. SMDs are typically arranged in series, with the product of one becoming the feed for the other. This has the advantage that each SMD in the line can have its media and operating conditions optimized to the particle size of its particular feed. The largest installed power in a KnelsonDeswik mill is 699kW[5]; this places it in an intermediate position between the 355-kW and 1.1-MW SMDs.

In 2012, FLSmidth reported that it had acquired the KnelsonDeswik mill; the mill is now known as the FLSmidth stirred mill. An FLSmidth stirred mill will be installed to perform a copper concentrate regrind in Mongolia.[9] It is speculated that the mill will continue to be scaled up under its new owners to allow it to effectively compete against the SMD and Isamill.

Gravity-induced stirred (GIS) mills include the Tower mill, produced by Nippon Eirich, and the Vertimill, produced by Metso. Grinding to below 40m in GIS mills or ball mills is usually not recommended. In their product literature, Metso give 40m as the lower end of the optimal P80 range for Vertimills.[6] At lower product sizes, both tower mills and ball mills will overgrind fines. At Mt. Isa Mines, a GIS mill fed with material of F80 approximately 50m lowered the P80 size by only 5 to 10m, at the same time producing a large amount of fines.[10] Similarly, in ball mills, it is known that grinding finer than approximately 40m will result in overgrinding of fines as well as high media consumption. However, it must be noted that the product size to which a mill can efficiently grind depends on the feed material, the F80, and media type and size. A Vertimill has been used to grind to sizes below 10m.[11]

The phenomenon of overgrinding is largely the result of using media that are too large for the product size generated. The smallest ball size typically charged into ball mills and tower mills is inch (12.5mm), although media diameters as small as 6mm have been used industrially in Vertimills.[11]

In a laboratory study by Nesset et al.,[7] a GIS mill charged with 5-mm steel shot, and with other operating conditions similarly optimized, achieved high energy efficiencies when grinding to less than 20m. This appears to qualitatively confirm the notion that fine grinding requires smaller media sizes. In the case of the Nesset study, the power intensity applied to the laboratory tower mill was lowthat is, the shaft was rotated slowly in order to obtain this high efficiency, leading to low throughput. This suggests that charging GIS mills with small media may not be practicable in plant operation.

Millpebs have been used as grinding media to achieve fine grinding in ball mills. These are 5- to 12-mm spherical or oblong cast steel pellets, charged into ball mills as a replacement of, or in addition to, balls. While Millpebs can give significantly lower energy use when grinding to finer sizes, they also can lead to high fines production and high media use.

Millpebs were tested for fine grinding at the Brunswick concentrator. The regrind ball mills at the concentrator used 25-mm slugs to produce a P80 of 28m. In one of the regrind mills, the slugs were replaced by Millpebs; these were able to consistently maintain a P80 of 22m while decreasing the power draw by 20pct. However, media use increased by 50pct and the production of fines of less than 16m diameter increased by a factor of 5.[12] The observed drop in specific energy may be due to the fact that Millpebs had smaller average diameters than the slugs and so were more efficient at grinding to the relatively small product sizes required. It is therefore unclear whether the performance of Millpebs would be better than that of conventional 12-mm steel balls. To the best of the authors knowledge, no performance comparison between Millpebs and similarly sized balls has been performed.

A host of other technologies exist to produce fine grinding, including jet mills, vibrating mills, roller mills, etc. However, none of these technologies has reached the same unit installed power as stirred mills. For example, one of the largest vibrating mills has an installed power of 160kW.[13] Therefore, these mills are considered as filling niche roles and are not treated further in this review. A fuller discussion of other fine grinding technologies can be found in a review by Orumwense and Forssberg.[14]

Neese et al.[15] subjected 50- to 150-m sand contaminated with oil to cleaning in a stirred mill in the laboratory. The mill operated at low stress intensities: A low speed and small-size media (200- to 400-m quartz or steel beads) were used. These conditions allowed the particles to be attrited without being broken. As a result, a large part of the oil contaminants was moved to the 5-m portion of the product. This treatment may hold promise as an alternative means of processing bituminous sands, for example, in northern Alberta.

The Albion process uses ultrafine grinding to enhance the oxidation of sulfide concentrates in treating refractory gold ores.[16] In the process, the flotation concentrate is ground to a P80 of 10 to 12m. The product slurry is reacted with oxygen in a leach tank at atmospheric pressure; limestone is added to maintain the pH at 5 to 5.5. The leach reaction is autothermal and is maintained near the slurry boiling point. Without the fine grinding step, an autoclave would be required for the oxygen leaching process. It is hypothesized that the fine grinding enhances leach kinetics by increasing the surface area of the particles, as well as by deforming the crystal lattices of the particles.

Numerous researchers, for example, Buys et al.,[17] report that stirred milling increases downstream flotation recoveries by cleaning the surface of the particles. The grinding media used in stirred mills are inert, and therefore corrosion reactions, which occur with steel media in ball mills, are not encountered. Corrosion reactions change the surface chemistry of particles, especially with sulfide feeds, and hamper downstream flotation.

Further increases in flotation recoveries are obtained by limiting the amount of ultrafine particles formed; stirred mills can selectively grind the larger particles in the feed with little increase in ultrafines production. Ultrafine particles are difficult to recover in flotation.

In intermediate grinding to approximately 75m, the Bond equation (Eq. [1]) is used to relate feed size, product size, and mechanical energy applied. Below 75m, correction factors can be applied to extend its range of validity.[4]

No general work index formula governing energy use over a range of conditions, like the Bond equation for intermediate grinding, has yet been found for the fine grinding regime. Instead, the work-to-P80 curve is determined in the laboratory for each case. The energy use usually fits an equation of the form

Signature plot (specific energy vs P80 curve) for Brunswick concentrator Zn circuit ball mill cyclone underflow; F80=63m. The plots give results for grinding the same feed using different mills and media. After Nesset et al.[7]

Values for the exponent k have been found in the range 0.7 to 3.5, meaning that the work to grind increases more rapidly as grind size decreases than in intermediate grinding. The specific energy vs product size curve has a much steeper slope in this region than in intermediate grinding.

The values of k and A are specific to the grinding conditions used in the laboratory tests. Changes in feed size, media size distribution, and in other properties such as media sphericity and hardness can change both k and A, often by very large amounts. Media size and F80 appear to be the most important determinants of the signature plot equation.

The connections (if any) between k and A and various operating conditions remain unknown. Because of the relatively recent advent of stirred milling in mineral processing, fine grinding has not been studied to the same extent as grinding in ball mills (which of course entail much larger capital and energy expenditures in any case). One of the research priorities in the field of stirred milling should be the investigation of the effects of F80 and media size on the position of the signature plots. If analogous formulas to the Bond ball mill work formula and the Bond top ball size formula can be found, the amount of test work required for stirred milling would be greatly reduced.

Larson et al.[19] found that when specific energy is plotted against the square of the percent particles in the product passing a given size (a proxy for particle surface area), a straight line is obtained. This is demonstrated in Figure3.

In contrast to the conventional signature plot, this function gives zero energy at the mill feed. It is therefore hypothesized that if a squared function plot is obtained by test work for one feed particle size, the plot for another feed particle size can be obtained simply by changing the intercept of the line while keeping the slope the same. Therefore, the squared function plot allows the effect of changes in both F80 and P80 to be modeled.

While the Squared Function Plot is intriguing, experimental validation of its applicability has not yet been published. It nevertheless remains an interesting topic for further investigation and if validated may be used in the future as an alternative measure of specific energy.

A similar analysis has been performed by Musa and Morrison,[21] who developed a model to determine the surface area within each size fraction of mill product. They defined a marker size below which 70 to 80pct of the product surface area was contained; the marker size thus served as a proxy for surface area production. Specific energy use was then defined as kWh of power per the tonne of new material generated below the marker size. Musa and Morrison found that by defining specific energy in this way, it was possible to accurately predict the performance of full-scale Vertimills and Isamills from laboratory tests.

Blecher and coworkers[22,23] found that stress intensity combines the most important variables determining milling performance. Stress intensity for a horizontal stirred mill, with media much harder than the mineral to be ground, is defined as in Eq. [4].

Note that the stress intensity is strongly sensitive to changes in media diameter (to the third power), is less sensitive to stirrer tip speed (to the second power), and is relatively insensitive to media and slurry density.

For vertical stirred mills such as the SMD and tower mill, both SIs and SIg are non-zero. For horizontal stirred mills such as the Isamill, net gravitational SI is zero due to symmetry along the horizontal axis. Therefore, for horizontal stirred mills, only SIs need be taken into consideration.

Kwade and coworkers noted that, at a given specific energy input, the product P80 obtainable varies with stress intensity and passes through a minimum. Product size at a given energy input can be viewed as a measure of milling efficiency; therefore, milling efficiency reaches a maximum at a single given stress intensity. This idea was experimentally validated by Jankovic and Valery (Figure 4).[25]

The stress intensity is defined by parameters that are independent of mill size or type. According to Jankovic and Valery,[25] once the optimum SI has been determined in one mill for a given feed, the same SI should also be the point of optimum efficiency in any other mill treating that feed. Therefore, the optimum SI need only be determined in one mill (e.g., a small test mill); the operating parameters of a full-scale mill need only be adjusted to produce the optimum SI.

Stress frequency multiplied by stress intensity is equal to mill power; therefore, stress intensity could in theory be used to predict mill specific energy. However, to the authors knowledge, a comprehensive model linking stress intensity, stress frequency, and specific energy has not yet been developed. Therefore, there is not yet any direct link between stress intensity and specific energy.

The definition of SIs as given in Eq. [4] is valid only for cases where the grinding media are much harder than that of the material ground (for example, the grinding of limestone with glass beads). Becker and Schwedes[26] determined that, in a collision between media and a mineral particle, the fraction of energy transferred to the product is given by Eq. [6]:

To maintain high efficiency in milling, the media must be chosen so as to be much harder (higher Youngs modulus) than the product material, keeping E p,rel close to unity. Where the Youngs modulus of the product is similar to that of the media, much of the applied energy goes into deformation of the media instead of that of the particle to be ground. The energy used to deform the media is lost, lowering the amount of energy transferred to the product. This fact explains why steel media, with a relatively low Youngs modulus, tend to perform poorly in stirred milling, even though the media are much more dense than silica or alumina media.

The previous sections indicated that stress intensity is independent from individual millsi.e., the optimal stress intensity when using Mill A will also be the optimal stress intensity when using Mill B. However, this does not seem to be the case when actually scaling up mills.

Four-liter Isamills are commonly used for grindability test work. It can be assumed that operating parameters of the test mill (including media type, media size, and slurry density) are adjusted so far as possible to give the optimum SI. These parameters are then used in the full-scale mill as well. However, the 4-L test mills have a tip speed of approximately 8m/s, while full-scale Isamills have tip speeds close to 20m/s.[27] If the same media size, media density, and slurry density are used in the test mill as in the full-scale mill, the stress intensity of the full-scale mill will be approximately 6.25 times larger than that of the test mill. This implies that the full-scale mill is operating outside of the optimum SI and will be grinding less efficiently. That is to say that the operating point of the full-scale mill will be above the signature plot determined by test work.

In reality, however, the operating points of full-scale stirred mills are generally found to lie on the signature plots generated in test work.[19] Therefore, the full-scale mills and test mills have the same milling efficiency, even though the full-scale mill operates at a different stress intensity than the test mill.

This question remains unresolved. One possible answer arises from the observation that two of the P80 vs SI curves in Figure4 appear to have broad troughs, covering almost an order of magnitude change in SI. In this case, even a sixfold increase in SI might not create a noticeable difference in performance, considering experimental and measurement error.

Product size vs stress intensity at three different specific energies for a zinc regrind. Note optimum stress intensity at which the lowest product size is reached. Figure used with permission from Jankovic and Valery[25]

The SMD test unit appears from photographs to have a bed depth of around 30cm, while the full-scale SMD355 has a bed depth of approximately one meter. This represents a change in the gravitational stress intensity of almost two orders of magnitude. As has been previously noted, however, laboratory and full-scale SMDs scale-up with a scale-up factor of approximately unity, with no apparent change in the optimum stress intensity. This observation suggests that the gravitational stress intensity, SIg, is unimportant in SMDs compared to the stirring stress intensity, SIs. By contrast, in GIS mills, where full-size units have bed depths of ten meters or more, gravitational stress intensity can be expected to be much more important in full-size units than in test units, adding a complicating factor to GIS mill scale-up.

Factorial design experiments were performed by Gao et al.[28] and Tuzun and Loveday[29] to determine the effect of various operating parameters on the power use of laboratory mills. Power models were determined giving the impact of different parameters as power equations with linear and nonlinear terms. The derived models did not appear to be applicable to mills other than the particular laboratory units being studied.

In ball milling, the Bond ball mill work index can be used to determine specific energy at a range of feed and product sizes. The Bond top size ball formula can be used to estimate the media size required. No such standard formulas exist in fine grinding. Energy and media parameters must instead be determined in the laboratory for every new combination of operating conditions such as feed size, media size, and media type.

For the Isamill, test work is usually performed with a 4-L bench-scale Isamill. Approximately 15kg of the material to be ground is slurried to 20pct solid density by volume. The slurry is then fed through the mill and mill power is measured. The products PSD is measured, additional water is added if needed, and the material is sent through the mill again. This continues until the target P80 is reached; typically, there will be 5 to 10 passes through the mill. The test work will produce a signature plot and media consumption data as the deliverables.

In contrast to laboratory-scale testing for ball mills and AG/SAG mills, test work results for stirred mills can be used for sizing full-size equipment with a scale-up factor close to one. Larson et al.[19,20] found a scale-up factor for the Isamill of exactly 1, while Gao et al.[8] imply that the scale-up factor for SMDs is 1.25.

A common error in test work is using monosize media (e.g., fresh 2-mm media loaded into in the mill) as opposed to aged media with a distribution of particle sizes. The aged media will grind the smaller feed particles more efficiently. Therefore, using fresh media will give a higher specific energy than in reality.[30]

Another pitfall is coarse holdup in the mill. If the mill is not sufficiently flushed, coarse particles will be kept inside the mill. The mill product then appears finer than it in reality is. This leads to lower estimates of specific energy than reality.[19]

In ball milling, the product particle size distribution (PSD) can usually be modeled as being parallel to the feed PSD on a log-linear plot.[4] When grinding to finer sizes in ball mills, the parallel PSDs mean that large amounts of ultrafine particles are produced. This consumes a large amount of grinding energy while producing particles which are difficult to recover in subsequent processing steps such as flotation.

As shown in the figure, at the left end of the graph, the product PSD is very close to the feed PSD; at the right, the two PSDs are widely spaced. This indicates that the mill is efficiently using its energy to break the top size particles and is spending very little energy on further grinding of fine particles. Thus, the overall energy efficiency of the fine grinding can be expected to be good. As a bonus, the tighter PSD makes control of downstream processes such as flotation easier.

In an experimental study, Jankovic and Sinclair subjected calcite and silica to fine grinding in a laboratory pin stirred mill, a Sala agitated mill (SAM), and a pilot tower mill. The authors found that for each mill, the PSD of the product was narrower (steeper) than that of the feed. In addition, when grinding to P80s below approximately 20m in any of the three mills tested, the PSD became more narrow (as measured by P80/P20 ratio) as the P80 decreased. (When the width of the PSD was calculated using an alternative formula, the PSD was only observed to narrow with decreasing P80 when using the pin stirred mill.) The authors concluded that the width of the PSD was strongly affected by the material properties of the feed, while not being significantly affected by the media size used.[32]

In stirred milling, the most commonly used media are ceramic balls of 1 to 5mm diameter. The ceramic is usually composed of alumina, an alumina/zirconia blend, or zirconium silicate. Ceramic media exist over a wide range of quality and cost, with the lower quality/cost ceramic having a higher wear rate than higher quality/cost ceramic. Other operations have used sand as media, but at the time of writing, only two operations continue to use sand.[8,27,33] Mt Isa Mines has used lead smelter slag as media; however, it is now using sand media.[10,27] Mt Isa is an exception in its use of slag, as a vast majority of operations do not have a smelter on-site to provide a limitless supply of free grinding media. However, in locations where slag is available, it should be considered as another source of media.

Media use in fine grinding is considered to be proportional to the mechanical energy applied. Typical wear rates and costs are given in TableIII and Figure6; these figures can of course vary significantly from operation to operation.

Contained energy refers to the energy required to produce and transport the media, and is distinct from the mechanical (electrical) energy used to drive the mill. Hammond and Jones estimated the contained energy in household ceramics (not taking account of transportation).[39] Hammond and Jones estimates range from 2.5 to 29.1MJ/kg, with 10MJ/kg for general ceramics and 29MJ/kg for sanitary ceramics. Given that ceramic grinding media require very good hardness and strength, especially compared to household ceramics, it is appropriate to estimate its contained energy at the top end of Hammond and Jones range, at 29MJ/kg.

Using 29MJ/kg for the contained energy of ceramic media and a wear rate of 35g/kWh of mechanical energy gives a contained energy consumption of 0.28kWh contained per kWh of mechanical energy applied. A wear rate of 7g/kWh gives a contained energy consumption of 0.06kWh contained per kWh of mechanical energy applied. Therefore, 6 to 20pct of the energy use in fine grinding using ceramic media can be represented by contained energy in the grinding media itself.

Sand media have much lower contained energy than ceramic media as the media must simply be mined or quarried rather than manufactured. Hammond and Jones report a contained energy of 0.1MJ/kg. Blake et al.[36] reported that switching a stirred mills media from sand to ceramic results in a mechanical energy savings of 20pct. Therefore, using sand rather than ceramic media would produce savings in contained energy, but would cost more in mechanical energy. Likewise, Davey[40] suggests that poor-quality media will increase mechanical energy use in stirred milling. It is speculated that this is due to the lower sphericity of sand media. On the other hand, the work of Nesset et al.[7] suggests that the energy use between ceramic and sand media of the same size is the same. Slag media, where a smelter is on-site, would probably have the lowest contained energy consumption of the different media types. There is very little transportation, and for accounting purposes, almost no energy has gone into creating the media as the granulated slag is a by-product of smelter operation.

Becker and Schwedes[41] point out that with poor-quality media, a significant part of the product will consist of broken pieces of media, which will affect the measured product PSD. Clearly, more information on the relationships between contained energy in media and media wear rates is desirable.

Of the different operating parameters for stirred mills, media size probably has the biggest influence on overall energy consumption. The appropriate media size for a mill appears to be a function of the F80 and P80 required. The grinding media must be large enough to break up the largest particles fed to the mill and small enough to grind the material to the product fineness desired. As demonstrated by the experience of Century mine, an inappropriate media size choice can result in energy consumption double that of optimum operation.[8]

In their laboratory study, Nesset et al.[7] varied a number of operating parameters for stirred mills and identified media size as having the largest impact on energy use. It was also noted that the trials which produced the sharpest product PSD were also the ones which resulted in the lowest specific energy use.

Gao et al.[8] report that at Century mine, the grinding media in SMDs performing regrind duty were changed from 1 to 3mm. This resulted in a drop in energy use of approximately 50pct; the signature plot shifted significantly downward (Figure7).

Figure8 shows the product PSD for laboratory SMD tests using 1- and 3-mm media. The PSD for the test using 1-mm media shows that the SMD produced a significant amount of fines (20pct below 4m). The mill also had difficulty breaking the top size particlesthe 100pct passing size appears to be almost the same for both the feed and the product. In contrast, the PSD using 3-mm media shows less fines production (20pct below 9m) and effective top size breakage, with all the particles above 90m broken. This is in line with the observation of Nesset et al.[7] that low energy use is associated with tight product size distributions.

Gao et al.[38] tested copper reverberatory furnace slag (CRFS, SG 3.8) and heavy media plant rejects (HMPR, SG 2.4) in a laboratory stirred mill at two sizes: 0.8/+0.3mm, and 1.7/+0.4mm. For both CRFS and HMPR, the smaller size media gave a lower specific energy than the larger size media. At the same size, both CRFS and HMPR had similar specific energy use. However, the CRFS ground the material much faster than HMPR. Possibly, this was due to its higher density.

Data on F80, P80, and media size were compiled from the literature in order to allow benchmarking against existing operations. The sources are listed in Table IV. F80 and P80 were plotted against media size; the results are given in Figure9.

F80 plotted against media size (blue diamonds); P80 plotted against media size (red crosses). Century UFG=Century ultrafine grind; Century Regr.=Century regrind. Data are taken from Case studies table (Color figure online)

It can be seen from the figure that as the P80 achieved decreases, the media size does as well, from 3mm to achieve 45m to 1mm to achieve under 10m. The F80 decreases with media size in a similar way, from 90m at 3mm to 45m at 1mm. Dotted lines have been added to Figure7 to define the region of operation of mills; these delimit a zone in which the stirred mill can be expected to operate efficiently.

In general, for a particular media size, limits on both F80 and P80 must be respected. For example, the figure suggests that a mill operating with an F80 of 100m should use 3-mm media, while a mill grinding to below 10m would need to use 1-mm media. To reduce a feed of 90m F80 to 10m P80, Figure9 suggests that comminution be done in two stages (two Isamills or SMDs in series) for optimal efficiency. The first stage would grind the feed from 90m to perhaps 45m using 3-mm media, while the second would grind from 45 to 10m using 1- or 2-mm media.

A number of opportunities exist to reduce the energy footprint of fine grinding mills. There are no general formulas, such as the Bond work formula and Bond top size ball formula in ball milling, to describe the performance of stirred mills. Therefore, improvement opportunities must be quantified by performing appropriate test work.

In addition to obtaining the signature plot, the specific energy as a function of new surface area should be determined during test work. This could be done either by the method of Larsen or by that of Musa and Morrison. Defining specific energy as a function of new surface area may constitute a superior means of predicting the performance of full-scale mills, as opposed to defining specific energy as a function of feed tonnage.

Media size should be chosen with care. It is recommended that test work be done with several media sizes in order to locate the stress intensity optimum. Media size can be benchmarked against other operations using Figure9.

There are indications that lower-quality media, apart from degrading faster, require more mechanical energy for grinding due to factors such as lower sphericity. It is recommended to perform test work using media of different quality to determine the effect of media quality on energy use. Slag and sand media may also be considered. Subsequently, a trade-off study involving media cost, electricity cost, improvement in energy efficiency, and contained energy in media should be performed to identify the best media from an economic and energy footprint standpoint.

D. Rahal, D. Erasmus, and K. Major: KnelsonDeswick Milling Technology: Bridging the Gap Between Low and High Speed Stirred Mills, Paper presented at the 43rd Canadian Mineral Processors Meeting, Ottawa, 2011.

Metso: Stirred milling: Vertimill grinding mills and Stirred Media Detritor (product brochure), 2013, available at http://www.metso.com/miningandconstruction/MaTobox7.nsf/DocsByID/F58680427E2A748F852576C4005210AC/$File/Stirred_Mills_Brochure-2011_LR.pdf, accessed April 21, 2013.

J. Nesset, P. Radziszewski, C. Hardie, and D. Leroux: Assessing the Performance and Efficiency of Fine Grinding Technologies, Paper presented at the 38th Canadian Mineral Processors Meeting, Ottawa, 2006.

FLSmidth: Acquisition enhances our precious metals offerings, 2012, FLSmidth eHighlights April 2012, available at http://www.flsmidth.com/en-US/eHighlights/Archive/Minerals/2012/April/Acquisition+enhances+our+precious+metals+offerings, accessed 17 April 2013.

S. Buys, C. Rule, and D. Curry: The Application of Large Scale Stirred Milling to the Retreatment of Merensky Platinum Tailings, Paper presented at the 37th Canadian Mineral Processors Meeting, Ottawa, 2005.

D. Curry, M. Cooper, J. Rubenstein, T. Shouldice, and M. Young: The Right Tools in the Right Place: How Xstrata Nickel Australasia Increased Ni Throughput at Its Cosmos Plant, Paper presented at the 42nd Canadian Mineral Processors conference, Ottawa, 2010.

G. Davey: Fine Grinding Applications Using the Metso Vertimill Grinding Mill and the Metso Stirred Media Detritor (SMD) in Gold Processing, Paper presented at the 38th Canadian Mineral Processors Meeting, Ottawa, 2006.

outotec minerals processing solutions - mining technology | mining news and views updated daily

outotec minerals processing solutions - mining technology | mining news and views updated daily

Outotec provides complete mineral processing solutions that are customised to your specific requirements. The comprehensive portfolio of various technologies treats virtually all ore types efficiently and cost-effectively. With more than a century of experience in the mining sector and a mindset to continuously develop new and innovative technology, Outotec has the expertise and capability for designing, supplying, and constructing modern state-of-the-art mineral processing plants with fast and reliable ramp-up to meet any requirement. Outotecs global network ensures close collaboration with customers worldwide during the entire plant lifecycle.

Outotec provides complete mineral processing solutions that are customised to your specific requirements. The comprehensive portfolio of various technologies treats virtually all ore types efficiently and cost-effectively. With more than a century of experience in the mining sector and a mindset to continuously develop new and innovative technology, Outotec has the expertise and capability for designing, supplying, and constructing modern state-of-the-art mineral processing plants with fast and reliable ramp-up to meet any requirement. Outotecs global network ensures close collaboration with customers worldwide during the entire plant lifecycle.

With more than a century of experience in the mining sector and a mindset to continuously develop new and innovative technology, Outotec has the expertise and capability for designing, supplying, and constructing modern state-of-the-art mineral processing plants with fast and reliable ramp-up to meet any requirement. Outotecs global network ensures close collaboration with customers worldwide during the entire plant lifecycle.

Outotec provides front-line process solutions for a wide variety of mineral processing applications: Base metals Precious metals Iron ore Chromite and ilmenite ores Different industrial minerals Smelter slags Outotec offers solutions from equipment to complete production plants, always tailor-made to the customers needs. Combined with our proven technologies, our extensive mineral processing experience and industry knowledge with multiple plant references make us a unique strategic partner in the mining industry. Focusing on minerals processing, metals production and technology development, our in-house R&D facilities feature state-of-the-art laboratories and pilot plants for challenging extractive metallurgy and minerals processing testwork. Our innovative HSC Chemistry software effectively simulates processes by using the data received from the testwork. Proprietary equipment for mineral processing solutions The demand for ever increasing capacities requires reliable and high throughput machinery. The Outotec range of equipment meet the requirements of any application. We offer an extensive range of grinding mills, flotation cells, and dewatering equipment with a high level of automation and process control to optimize plant performance. Grinding mills Outotecs comminution equipment includes autogenous (AG) and semi-autogenous (SAG) mills, rod mills, ball mills, and pebble mills. A wide variety of mill designs are available to suit your specifications in either greenfield projects or existing operations as upgrades. We have expanded our grinding mill portfolio with the Outotec High-Intensity Grinding Mill (Outotec HIGMillTM) for fine, ultra-fine, and regrind milling applications. Flotation machines Outotecs flotation solutions are tailor-made to customers needs; be it a question of flotation packages with support services, modular process sections or concentrator solutions. FloatForce, Outotecs innovative flotation mechanism, improves metallurgical performance and reduces the energy consumption of flotation operations. This rotor-stator design can be directly retrofitted to Outotecs OK, TankCell and SkimAir flotation cells to improve their mixing profiles and solids suspension. Thickeners Outotec is a leading manufacturer of thickening and clarifying solutions for the minerals industry. Our Outotec High Rate Thickener has pioneered thickening and clarifying methods worldwide. A number of significant thickening advances include: Low-profile triangular rake arms to decrease rake torque Outotec Directional Autodil and Outotec Turbodil: the worlds first thickening systems to auto-dilute feed, which effectively optimises flocculant consumption and performance Outotec FrothBuster: a deaerator that reduce the amount of froth forming on the surface of thickeners, automatic de-scaling of thickener rakes, and the complete redesign of thickener drives to use low-cost, efficient epicyclic gearboxes Outotec Vane Feedwell: a major innovation in the thickening industry, it incorporates a cutting-edge design, and features interconnected upper and lower zones. Filters Outotec is a leading industrial filtration solutions provider with full after sales services for solid-liquid separation. Mining and metallurgy, chemical process, and related industries benefit from our high-efficiency process technologies, products, and solutions. Outotec Larox filtration technologies are based either on overpressure, including automatic vertical pressure filters, horizontal filter presses, and polishing filters, or on under-pressure, including horizontal vacuum belt filters, ceramic disc filters, and conventional vacuum disc and drum filters. Most of the products have served the markets for several decades and all are supported by Outotec services. Analyzers and automation Outotec is a leading supplier of intelligent instruments, sampling systems, and advanced process automation for mineral and metal processing industries. Among the most well-known Outotec products in this field are Outotec Courier on-stream XRF analyzers that enable the real-time assaying of slurry process streams of all types of mineral processing plants. Online particle size analysis by Outotec PSI, combined with advanced control enables optimum grind size with maximum throughput to be maintained regardless of variations in feed quality. The Outotec Proscon and Outotec ACT (Advanced Control Tools) are process control systems and optimizing solutions for unit processes and complete processing plants. The systems comprise design, implementation, maintenance, and all the necessary hardware and software. Press Releases Introducing a Webinar on Outotec HIGmill Technology for Fine and Ultrafine Grinding In the past seven years, Outotec HIG mills have been marketed, tested, sold and commissioned... Company Links www.outotec.com

Outotec offers solutions from equipment to complete production plants, always tailor-made to the customers needs. Combined with our proven technologies, our extensive mineral processing experience and industry knowledge with multiple plant references make us a unique strategic partner in the mining industry. Focusing on minerals processing, metals production and technology development, our in-house R&D facilities feature state-of-the-art laboratories and pilot plants for challenging extractive metallurgy and minerals processing testwork. Our innovative HSC Chemistry software effectively simulates processes by using the data received from the testwork. Proprietary equipment for mineral processing solutions The demand for ever increasing capacities requires reliable and high throughput machinery. The Outotec range of equipment meet the requirements of any application. We offer an extensive range of grinding mills, flotation cells, and dewatering equipment with a high level of automation and process control to optimize plant performance. Grinding mills Outotecs comminution equipment includes autogenous (AG) and semi-autogenous (SAG) mills, rod mills, ball mills, and pebble mills. A wide variety of mill designs are available to suit your specifications in either greenfield projects or existing operations as upgrades. We have expanded our grinding mill portfolio with the Outotec High-Intensity Grinding Mill (Outotec HIGMillTM) for fine, ultra-fine, and regrind milling applications. Flotation machines Outotecs flotation solutions are tailor-made to customers needs; be it a question of flotation packages with support services, modular process sections or concentrator solutions. FloatForce, Outotecs innovative flotation mechanism, improves metallurgical performance and reduces the energy consumption of flotation operations. This rotor-stator design can be directly retrofitted to Outotecs OK, TankCell and SkimAir flotation cells to improve their mixing profiles and solids suspension. Thickeners Outotec is a leading manufacturer of thickening and clarifying solutions for the minerals industry. Our Outotec High Rate Thickener has pioneered thickening and clarifying methods worldwide. A number of significant thickening advances include: Low-profile triangular rake arms to decrease rake torque Outotec Directional Autodil and Outotec Turbodil: the worlds first thickening systems to auto-dilute feed, which effectively optimises flocculant consumption and performance Outotec FrothBuster: a deaerator that reduce the amount of froth forming on the surface of thickeners, automatic de-scaling of thickener rakes, and the complete redesign of thickener drives to use low-cost, efficient epicyclic gearboxes Outotec Vane Feedwell: a major innovation in the thickening industry, it incorporates a cutting-edge design, and features interconnected upper and lower zones. Filters Outotec is a leading industrial filtration solutions provider with full after sales services for solid-liquid separation. Mining and metallurgy, chemical process, and related industries benefit from our high-efficiency process technologies, products, and solutions. Outotec Larox filtration technologies are based either on overpressure, including automatic vertical pressure filters, horizontal filter presses, and polishing filters, or on under-pressure, including horizontal vacuum belt filters, ceramic disc filters, and conventional vacuum disc and drum filters. Most of the products have served the markets for several decades and all are supported by Outotec services. Analyzers and automation Outotec is a leading supplier of intelligent instruments, sampling systems, and advanced process automation for mineral and metal processing industries. Among the most well-known Outotec products in this field are Outotec Courier on-stream XRF analyzers that enable the real-time assaying of slurry process streams of all types of mineral processing plants. Online particle size analysis by Outotec PSI, combined with advanced control enables optimum grind size with maximum throughput to be maintained regardless of variations in feed quality. The Outotec Proscon and Outotec ACT (Advanced Control Tools) are process control systems and optimizing solutions for unit processes and complete processing plants. The systems comprise design, implementation, maintenance, and all the necessary hardware and software. Press Releases Introducing a Webinar on Outotec HIGmill Technology for Fine and Ultrafine Grinding In the past seven years, Outotec HIG mills have been marketed, tested, sold and commissioned... Company Links www.outotec.com

Focusing on minerals processing, metals production and technology development, our in-house R&D facilities feature state-of-the-art laboratories and pilot plants for challenging extractive metallurgy and minerals processing testwork. Our innovative HSC Chemistry software effectively simulates processes by using the data received from the testwork. Proprietary equipment for mineral processing solutions The demand for ever increasing capacities requires reliable and high throughput machinery. The Outotec range of equipment meet the requirements of any application. We offer an extensive range of grinding mills, flotation cells, and dewatering equipment with a high level of automation and process control to optimize plant performance. Grinding mills Outotecs comminution equipment includes autogenous (AG) and semi-autogenous (SAG) mills, rod mills, ball mills, and pebble mills. A wide variety of mill designs are available to suit your specifications in either greenfield projects or existing operations as upgrades. We have expanded our grinding mill portfolio with the Outotec High-Intensity Grinding Mill (Outotec HIGMillTM) for fine, ultra-fine, and regrind milling applications. Flotation machines Outotecs flotation solutions are tailor-made to customers needs; be it a question of flotation packages with support services, modular process sections or concentrator solutions. FloatForce, Outotecs innovative flotation mechanism, improves metallurgical performance and reduces the energy consumption of flotation operations. This rotor-stator design can be directly retrofitted to Outotecs OK, TankCell and SkimAir flotation cells to improve their mixing profiles and solids suspension. Thickeners Outotec is a leading manufacturer of thickening and clarifying solutions for the minerals industry. Our Outotec High Rate Thickener has pioneered thickening and clarifying methods worldwide. A number of significant thickening advances include: Low-profile triangular rake arms to decrease rake torque Outotec Directional Autodil and Outotec Turbodil: the worlds first thickening systems to auto-dilute feed, which effectively optimises flocculant consumption and performance Outotec FrothBuster: a deaerator that reduce the amount of froth forming on the surface of thickeners, automatic de-scaling of thickener rakes, and the complete redesign of thickener drives to use low-cost, efficient epicyclic gearboxes Outotec Vane Feedwell: a major innovation in the thickening industry, it incorporates a cutting-edge design, and features interconnected upper and lower zones. Filters Outotec is a leading industrial filtration solutions provider with full after sales services for solid-liquid separation. Mining and metallurgy, chemical process, and related industries benefit from our high-efficiency process technologies, products, and solutions. Outotec Larox filtration technologies are based either on overpressure, including automatic vertical pressure filters, horizontal filter presses, and polishing filters, or on under-pressure, including horizontal vacuum belt filters, ceramic disc filters, and conventional vacuum disc and drum filters. Most of the products have served the markets for several decades and all are supported by Outotec services. Analyzers and automation Outotec is a leading supplier of intelligent instruments, sampling systems, and advanced process automation for mineral and metal processing industries. Among the most well-known Outotec products in this field are Outotec Courier on-stream XRF analyzers that enable the real-time assaying of slurry process streams of all types of mineral processing plants. Online particle size analysis by Outotec PSI, combined with advanced control enables optimum grind size with maximum throughput to be maintained regardless of variations in feed quality. The Outotec Proscon and Outotec ACT (Advanced Control Tools) are process control systems and optimizing solutions for unit processes and complete processing plants. The systems comprise design, implementation, maintenance, and all the necessary hardware and software. Press Releases Introducing a Webinar on Outotec HIGmill Technology for Fine and Ultrafine Grinding In the past seven years, Outotec HIG mills have been marketed, tested, sold and commissioned... Company Links www.outotec.com

The demand for ever increasing capacities requires reliable and high throughput machinery. The Outotec range of equipment meet the requirements of any application. We offer an extensive range of grinding mills, flotation cells, and dewatering equipment with a high level of automation and process control to optimize plant performance. Grinding mills Outotecs comminution equipment includes autogenous (AG) and semi-autogenous (SAG) mills, rod mills, ball mills, and pebble mills. A wide variety of mill designs are available to suit your specifications in either greenfield projects or existing operations as upgrades. We have expanded our grinding mill portfolio with the Outotec High-Intensity Grinding Mill (Outotec HIGMillTM) for fine, ultra-fine, and regrind milling applications. Flotation machines Outotecs flotation solutions are tailor-made to customers needs; be it a question of flotation packages with support services, modular process sections or concentrator solutions. FloatForce, Outotecs innovative flotation mechanism, improves metallurgical performance and reduces the energy consumption of flotation operations. This rotor-stator design can be directly retrofitted to Outotecs OK, TankCell and SkimAir flotation cells to improve their mixing profiles and solids suspension. Thickeners Outotec is a leading manufacturer of thickening and clarifying solutions for the minerals industry. Our Outotec High Rate Thickener has pioneered thickening and clarifying methods worldwide. A number of significant thickening advances include: Low-profile triangular rake arms to decrease rake torque Outotec Directional Autodil and Outotec Turbodil: the worlds first thickening systems to auto-dilute feed, which effectively optimises flocculant consumption and performance Outotec FrothBuster: a deaerator that reduce the amount of froth forming on the surface of thickeners, automatic de-scaling of thickener rakes, and the complete redesign of thickener drives to use low-cost, efficient epicyclic gearboxes Outotec Vane Feedwell: a major innovation in the thickening industry, it incorporates a cutting-edge design, and features interconnected upper and lower zones. Filters Outotec is a leading industrial filtration solutions provider with full after sales services for solid-liquid separation. Mining and metallurgy, chemical process, and related industries benefit from our high-efficiency process technologies, products, and solutions. Outotec Larox filtration technologies are based either on overpressure, including automatic vertical pressure filters, horizontal filter presses, and polishing filters, or on under-pressure, including horizontal vacuum belt filters, ceramic disc filters, and conventional vacuum disc and drum filters. Most of the products have served the markets for several decades and all are supported by Outotec services. Analyzers and automation Outotec is a leading supplier of intelligent instruments, sampling systems, and advanced process automation for mineral and metal processing industries. Among the most well-known Outotec products in this field are Outotec Courier on-stream XRF analyzers that enable the real-time assaying of slurry process streams of all types of mineral processing plants. Online particle size analysis by Outotec PSI, combined with advanced control enables optimum grind size with maximum throughput to be maintained regardless of variations in feed quality. The Outotec Proscon and Outotec ACT (Advanced Control Tools) are process control systems and optimizing solutions for unit processes and complete processing plants. The systems comprise design, implementation, maintenance, and all the necessary hardware and software. Press Releases Introducing a Webinar on Outotec HIGmill Technology for Fine and Ultrafine Grinding In the past seven years, Outotec HIG mills have been marketed, tested, sold and commissioned... Company Links www.outotec.com

Grinding mills Outotecs comminution equipment includes autogenous (AG) and semi-autogenous (SAG) mills, rod mills, ball mills, and pebble mills. A wide variety of mill designs are available to suit your specifications in either greenfield projects or existing operations as upgrades. We have expanded our grinding mill portfolio with the Outotec High-Intensity Grinding Mill (Outotec HIGMillTM) for fine, ultra-fine, and regrind milling applications. Flotation machines Outotecs flotation solutions are tailor-made to customers needs; be it a question of flotation packages with support services, modular process sections or concentrator solutions. FloatForce, Outotecs innovative flotation mechanism, improves metallurgical performance and reduces the energy consumption of flotation operations. This rotor-stator design can be directly retrofitted to Outotecs OK, TankCell and SkimAir flotation cells to improve their mixing profiles and solids suspension. Thickeners Outotec is a leading manufacturer of thickening and clarifying solutions for the minerals industry. Our Outotec High Rate Thickener has pioneered thickening and clarifying methods worldwide. A number of significant thickening advances include: Low-profile triangular rake arms to decrease rake torque Outotec Directional Autodil and Outotec Turbodil: the worlds first thickening systems to auto-dilute feed, which effectively optimises flocculant consumption and performance Outotec FrothBuster: a deaerator that reduce the amount of froth forming on the surface of thickeners, automatic de-scaling of thickener rakes, and the complete redesign of thickener drives to use low-cost, efficient epicyclic gearboxes Outotec Vane Feedwell: a major innovation in the thickening industry, it incorporates a cutting-edge design, and features interconnected upper and lower zones. Filters Outotec is a leading industrial filtration solutions provider with full after sales services for solid-liquid separation. Mining and metallurgy, chemical process, and related industries benefit from our high-efficiency process technologies, products, and solutions. Outotec Larox filtration technologies are based either on overpressure, including automatic vertical pressure filters, horizontal filter presses, and polishing filters, or on under-pressure, including horizontal vacuum belt filters, ceramic disc filters, and conventional vacuum disc and drum filters. Most of the products have served the markets for several decades and all are supported by Outotec services. Analyzers and automation Outotec is a leading supplier of intelligent instruments, sampling systems, and advanced process automation for mineral and metal processing industries. Among the most well-known Outotec products in this field are Outotec Courier on-stream XRF analyzers that enable the real-time assaying of slurry process streams of all types of mineral processing plants. Online particle size analysis by Outotec PSI, combined with advanced control enables optimum grind size with maximum throughput to be maintained regardless of variations in feed quality. The Outotec Proscon and Outotec ACT (Advanced Control Tools) are process control systems and optimizing solutions for unit processes and complete processing plants. The systems comprise design, implementation, maintenance, and all the necessary hardware and software. Press Releases Introducing a Webinar on Outotec HIGmill Technology for Fine and Ultrafine Grinding In the past seven years, Outotec HIG mills have been marketed, tested, sold and commissioned... Company Links www.outotec.com

Outotecs comminution equipment includes autogenous (AG) and semi-autogenous (SAG) mills, rod mills, ball mills, and pebble mills. A wide variety of mill designs are available to suit your specifications in either greenfield projects or existing operations as upgrades. We have expanded our grinding mill portfolio with the Outotec High-Intensity Grinding Mill (Outotec HIGMillTM) for fine, ultra-fine, and regrind milling applications. Flotation machines Outotecs flotation solutions are tailor-made to customers needs; be it a question of flotation packages with support services, modular process sections or concentrator solutions. FloatForce, Outotecs innovative flotation mechanism, improves metallurgical performance and reduces the energy consumption of flotation operations. This rotor-stator design can be directly retrofitted to Outotecs OK, TankCell and SkimAir flotation cells to improve their mixing profiles and solids suspension. Thickeners Outotec is a leading manufacturer of thickening and clarifying solutions for the minerals industry. Our Outotec High Rate Thickener has pioneered thickening and clarifying methods worldwide. A number of significant thickening advances include: Low-profile triangular rake arms to decrease rake torque Outotec Directional Autodil and Outotec Turbodil: the worlds first thickening systems to auto-dilute feed, which effectively optimises flocculant consumption and performance Outotec FrothBuster: a deaerator that reduce the amount of froth forming on the surface of thickeners, automatic de-scaling of thickener rakes, and the complete redesign of thickener drives to use low-cost, efficient epicyclic gearboxes Outotec Vane Feedwell: a major innovation in the thickening industry, it incorporates a cutting-edge design, and features interconnected upper and lower zones. Filters Outotec is a leading industrial filtration solutions provider with full after sales services for solid-liquid separation. Mining and metallurgy, chemical process, and related industries benefit from our high-efficiency process technologies, products, and solutions. Outotec Larox filtration technologies are based either on overpressure, including automatic vertical pressure filters, horizontal filter presses, and polishing filters, or on under-pressure, including horizontal vacuum belt filters, ceramic disc filters, and conventional vacuum disc and drum filters. Most of the products have served the markets for several decades and all are supported by Outotec services. Analyzers and automation Outotec is a leading supplier of intelligent instruments, sampling systems, and advanced process automation for mineral and metal processing industries. Among the most well-known Outotec products in this field are Outotec Courier on-stream XRF analyzers that enable the real-time assaying of slurry process streams of all types of mineral processing plants. Online particle size analysis by Outotec PSI, combined with advanced control enables optimum grind size with maximum throughput to be maintained regardless of variations in feed quality. The Outotec Proscon and Outotec ACT (Advanced Control Tools) are process control systems and optimizing solutions for unit processes and complete processing plants. The systems comprise design, implementation, maintenance, and all the necessary hardware and software. Press Releases Introducing a Webinar on Outotec HIGmill Technology for Fine and Ultrafine Grinding In the past seven years, Outotec HIG mills have been marketed, tested, sold and commissioned... Company Links www.outotec.com

A wide variety of mill designs are available to suit your specifications in either greenfield projects or existing operations as upgrades. We have expanded our grinding mill portfolio with the Outotec High-Intensity Grinding Mill (Outotec HIGMillTM) for fine, ultra-fine, and regrind milling applications. Flotation machines Outotecs flotation solutions are tailor-made to customers needs; be it a question of flotation packages with support services, modular process sections or concentrator solutions. FloatForce, Outotecs innovative flotation mechanism, improves metallurgical performance and reduces the energy consumption of flotation operations. This rotor-stator design can be directly retrofitted to Outotecs OK, TankCell and SkimAir flotation cells to improve their mixing profiles and solids suspension. Thickeners Outotec is a leading manufacturer of thickening and clarifying solutions for the minerals industry. Our Outotec High Rate Thickener has pioneered thickening and clarifying methods worldwide. A number of significant thickening advances include: Low-profile triangular rake arms to decrease rake torque Outotec Directional Autodil and Outotec Turbodil: the worlds first thickening systems to auto-dilute feed, which effectively optimises flocculant consumption and performance Outotec FrothBuster: a deaerator that reduce the amount of froth forming on the surface of thickeners, automatic de-scaling of thickener rakes, and the complete redesign of thickener drives to use low-cost, efficient epicyclic gearboxes Outotec Vane Feedwell: a major innovation in the thickening industry, it incorporates a cutting-edge design, and features interconnected upper and lower zones. Filters Outotec is a leading industrial filtration solutions provider with full after sales services for solid-liquid separation. Mining and metallurgy, chemical process, and related industries benefit from our high-efficiency process technologies, products, and solutions. Outotec Larox filtration technologies are based either on overpressure, including automatic vertical pressure filters, horizontal filter presses, and polishing filters, or on under-pressure, including horizontal vacuum belt filters, ceramic disc filters, and conventional vacuum disc and drum filters. Most of the products have served the markets for several decades and all are supported by Outotec services. Analyzers and automation Outotec is a leading supplier of intelligent instruments, sampling systems, and advanced process automation for mineral and metal processing industries. Among the most well-known Outotec products in this field are Outotec Courier on-stream XRF analyzers that enable the real-time assaying of slurry process streams of all types of mineral processing plants. Online particle size analysis by Outotec PSI, combined with advanced control enables optimum grind size with maximum throughput to be maintained regardless of variations in feed quality. The Outotec Proscon and Outotec ACT (Advanced Control Tools) are process control systems and optimizing solutions for unit processes and complete processing plants. The systems comprise design, implementation, maintenance, and all the necessary hardware and software. Press Releases Introducing a Webinar on Outotec HIGmill Technology for Fine and Ultrafine Grinding In the past seven years, Outotec HIG mills have been marketed, tested, sold and commissioned... Company Links www.outotec.com

We have expanded our grinding mill portfolio with the Outotec High-Intensity Grinding Mill (Outotec HIGMillTM) for fine, ultra-fine, and regrind milling applications. Flotation machines Outotecs flotation solutions are tailor-made to customers needs; be it a question of flotation packages with support services, modular process sections or concentrator solutions. FloatForce, Outotecs innovative flotation mechanism, improves metallurgical performance and reduces the energy consumption of flotation operations. This rotor-stator design can be directly retrofitted to Outotecs OK, TankCell and SkimAir flotation cells to improve their mixing profiles and solids suspension. Thickeners Outotec is a leading manufacturer of thickening and clarifying solutions for the minerals industry. Our Outotec High Rate Thickener has pioneered thickening and clarifying methods worldwide. A number of significant thickening advances include: Low-profile triangular rake arms to decrease rake torque Outotec Directional Autodil and Outotec Turbodil: the worlds first thickening systems to auto-dilute feed, which effectively optimises flocculant consumption and performance Outotec FrothBuster: a deaerator that reduce the amount of froth forming on the surface of thickeners, automatic de-scaling of thickener rakes, and the complete redesign of thickener drives to use low-cost, efficient epicyclic gearboxes Outotec Vane Feedwell: a major innovation in the thickening industry, it incorporates a cutting-edge design, and features interconnected upper and lower zones. Filters Outotec is a leading industrial filtration solutions provider with full after sales services for solid-liquid separation. Mining and metallurgy, chemical process, and related industries benefit from our high-efficiency process technologies, products, and solutions. Outotec Larox filtration technologies are based either on overpressure, including automatic vertical pressure filters, horizontal filter presses, and polishing filters, or on under-pressure, including horizontal vacuum belt filters, ceramic disc filters, and conventional vacuum disc and drum filters. Most of the products have served the markets for several decades and all are supported by Outotec services. Analyzers and automation Outotec is a leading supplier of intelligent instruments, sampling systems, and advanced process automation for mineral and metal processing industries. Among the most well-known Outotec products in this field are Outotec Courier on-stream XRF analyzers that enable the real-time assaying of slurry process streams of all types of mineral processing plants. Online particle size analysis by Outotec PSI, combined with advanced control enables optimum grind size with maximum throughput to be maintained regardless of variations in feed quality. The Outotec Proscon and Outotec ACT (Advanced Control Tools) are process control systems and optimizing solutions for unit processes and complete processing plants. The systems comprise design, implementation, maintenance, and all the necessary hardware and software. Press Releases Introducing a Webinar on Outotec HIGmill Technology for Fine and Ultrafine Grinding In the past seven years, Outotec HIG mills have been marketed, tested, sold and commissioned... Company Links www.outotec.com

Flotation machines Outotecs flotation solutions are tailor-made to customers needs; be it a question of flotation packages with support services, modular process sections or concentrator solutions. FloatForce, Outotecs innovative flotation mechanism, improves metallurgical performance and reduces the energy consumption of flotation operations. This rotor-stator design can be directly retrofitted to Outotecs OK, TankCell and SkimAir flotation cells to improve their mixing profiles and solids suspension. Thickeners Outotec is a leading manufacturer of thickening and clarifying solutions for the minerals industry. Our Outotec High Rate Thickener has pioneered thickening and clarifying methods worldwide. A number of significant thickening advances include: Low-profile triangular rake arms to decrease rake torque Outotec Directional Autodil and Outotec Turbodil: the worlds first thickening systems to auto-dilute feed, which effectively optimises flocculant consumption and performance Outotec FrothBuster: a deaerator that reduce the amount of froth forming on the surface of thickeners, automatic de-scaling of thickener rakes, and the complete redesign of thickener drives to use low-cost, efficient epicyclic gearboxes Outotec Vane Feedwell: a major innovation in the thickening industry, it incorporates a cutting-edge design, and features interconnected upper and lower zones. Filters Outotec is a leading industrial filtration solutions provider with full after sales services for solid-liquid separation. Mining and metallurgy, chemical process, and related industries benefit from our high-efficiency process technologies, products, and solutions. Outotec Larox filtration technologies are based either on overpressure, including automatic vertical pressure filters, horizontal filter presses, and polishing filters, or on under-pressure, including horizontal vacuum belt filters, ceramic disc filters, and conventional vacuum disc and drum filters. Most of the products have served the markets for several decades and all are supported by Outotec services. Analyzers and automation Outotec is a leading supplier of intelligent instruments, sampling systems, and advanced process automation for mineral and metal processing industries. Among the most well-known Outotec products in this field are Outotec Courier on-stream XRF analyzers that enable the real-time assaying of slurry process streams of all types of mineral processing plants. Online particle size analysis by Outotec PSI, combined with advanced control enables optimum grind size with maximum throughput to be maintained regardless of variations in feed quality. The Outotec Proscon and Outotec ACT (Advanced Control Tools) are process control systems and optimizing solutions for unit processes and complete processing plants. The systems comprise design, implementation, maintenance, and all the necessary hardware and software. Press Releases Introducing a Webinar on Outotec HIGmill Technology for Fine and Ultrafine Grinding In the past seven years, Outotec HIG mills have been marketed, tested, sold and commissioned... Company Links www.outotec.com

Outotecs flotation solutions are tailor-made to customers needs; be it a question of flotation packages with support services, modular process sections or concentrator solutions. FloatForce, Outotecs innovative flotation mechanism, improves metallurgical performance and reduces the energy consumption of flotation operations. This rotor-stator design can be directly retrofitted to Outotecs OK, TankCell and SkimAir flotation cells to improve their mixing profiles and solids suspension. Thickeners Outotec is a leading manufacturer of thickening and clarifying solutions for the minerals industry. Our Outotec High Rate Thickener has pioneered thickening and clarifying methods worldwide. A number of significant thickening advances include: Low-profile triangular rake arms to decrease rake torque Outotec Directional Autodil and Outotec Turbodil: the worlds first thickening systems to auto-dilute feed, which effectively optimises flocculant consumption and performance Outotec FrothBuster: a deaerator that reduce the amount of froth forming on the surface of thickeners, automatic de-scaling of thickener rakes, and the complete redesign of thickener drives to use low-cost, efficient epicyclic gearboxes Outotec Vane Feedwell: a major innovation in the thickening industry, it incorporates a cutting-edge design, and features interconnected upper and lower zones. Filters Outotec is a leading industrial filtration solutions provider with full after sales services for solid-liquid separation. Mining and metallurgy, chemical process, and related industries benefit from our high-efficiency process technologies, products, and solutions. Outotec Larox filtration technologies are based either on overpressure, including automatic vertical pressure filters, horizontal filter presses, and polishing filters, or on under-pressure, including horizontal vacuum belt filters, ceramic disc filters, and conventional vacuum disc and drum filters. Most of the products have served the markets for several decades and all are supported by Outotec services. Analyzers and automation Outotec is a leading supplier of intelligent instruments, sampling systems, and advanced process automation for mineral and metal processing industries. Among the most well-known Outotec products in this field are Outotec Courier on-stream XRF analyzers that enable the real-time assaying of slurry process streams of all types of mineral processing plants. Online particle size analysis by Outotec PSI, combined with advanced control enables optimum grind size with maximum throughput to be maintained regardless of variations in feed quality. The Outotec Proscon and Outotec ACT (Advanced Control Tools) are process control systems and optimizing solutions for unit processes and complete processing plants. The systems comprise design, implementation, maintenance, and all the necessary hardware and software. Press Releases Introducing a Webinar on Outotec HIGmill Technology for Fine and Ultrafine Grinding In the past seven years, Outotec HIG mills have been marketed, tested, sold and commissioned... Company Links www.outotec.com

FloatForce, Outotecs innovative flotation mechanism, improves metallurgical performance and reduces the energy consumption of flotation operations. This rotor-stator design can be directly retrofitted to Outotecs OK, TankCell and SkimAir flotation cells to improve their mixing profiles and solids suspension. Thickeners Outotec is a leading manufacturer of thickening and clarifying solutions for the minerals industry. Our Outotec High Rate Thickener has pioneered thickening and clarifying methods worldwide. A number of significant thickening advances include: Low-profile triangular rake arms to decrease rake torque Outotec Directional Autodil and Outotec Turbodil: the worlds first thickening systems to auto-dilute feed, which effectively optimises flocculant consumption and performance Outotec FrothBuster: a deaerator that reduce the amount of froth forming on the surface of thickeners, automatic de-scaling of thickener rakes, and the complete redesign of thickener drives to use low-cost, efficient epicyclic gearboxes Outotec Vane Feedwell: a major innovation in the thickening industry, it incorporates a cutting-edge design, and features interconnected upper and lower zones. Filters Outotec is a leading industrial filtration solutions provider with full after sales services for solid-liquid separation. Mining and metallurgy, chemical process, and related industries benefit from our high-efficiency process technologies, products, and solutions. Outotec Larox filtration technologies are based either on overpressure, including automatic vertical pressure filters, horizontal filter presses, and polishing filters, or on under-pressure, including horizontal vacuum belt filters, ceramic disc filters, and conventional vacuum disc and drum filters. Most of the products have served the markets for several decades and all are supported by Outotec services. Analyzers and automation Outotec is a leading supplier of intelligent instruments, sampling systems, and advanced process automation for mineral and metal processing industries. Among the most well-known Outotec products in this field are Outotec Courier on-stream XRF analyzers that enable the real-time assaying of slurry process streams of all types of mineral processing plants. Online particle size analysis by Outotec PSI, combined with advanced control enables optimum grind size with maximum throughput to be maintained regardless of variations in feed quality. The Outotec Proscon and Outotec ACT (Advanced Control Tools) are process control systems and optimizing solutions for unit processes and complete processing plants. The systems comprise design, implementation, maintenance, and all the necessary hardware and software. Press Releases Introducing a Webinar on Outotec HIGmill Technology for Fine and Ultrafine Grinding In the past seven years, Outotec HIG mills have been marketed, tested, sold and commissioned... Company Links www.outotec.com

Thickeners Outotec is a leading manufacturer of thickening and clarifying solutions for the minerals industry. Our Outotec High Rate Thickener has pioneered thickening and clarifying methods worldwide. A number of significant thickening advances include: Low-profile triangular rake arms to decrease rake torque Outotec Directional Autodil and Outotec Turbodil: the worlds first thickening systems to auto-dilute feed, which effectively optimises flocculant consumption and performance Outotec FrothBuster: a deaerator that reduce the amount of froth forming on the surface of thickeners, automatic de-scaling of thickener rakes, and the complete redesign of thickener drives to use low-cost, efficient epicyclic gearboxes Outotec Vane Feedwell: a major innovation in the thickening industry, it incorporates a cutting-edge design, and features interconnected upper and lower zones. Filters Outotec is a leading industrial filtration solutions provider with full after sales services for solid-liquid separation. Mining and metallurgy, chemical process, and related industries benefit from our high-efficiency process technologies, products, and solutions. Outotec Larox filtration technologies are based either on overpressure, including automatic vertical pressure filters, horizontal filter presses, and polishing filters, or on under-pressure, including horizontal vacuum belt filters, ceramic disc filters, and conventional vacuum disc and drum filters. Most of the products have served the markets for several decades and all are supported by Outotec services. Analyzers and automation Outotec is a leading supplier of intelligent instruments, sampling systems, and advanced process automation for mineral and metal processing industries. Among the most well-known Outotec products in this field are Outotec Courier on-stream XRF analyzers that enable the real-time assaying of slurry process streams of all types of mineral processing plants. Online particle size analysis by Outotec PSI, combined with advanced control enables optimum grind size with maximum throughput to be maintained regardless of variations in feed quality. The Outotec Proscon and Outotec ACT (Advanced Control Tools) are process control systems and optimizing solutions for unit processes and complete processing plants. The systems comprise design, implementation, maintenance, and all the necessary hardware and software. Press Releases Introducing a Webinar on Outotec HIGmill Technology for Fine and Ultrafine Grinding In the past seven years, Outotec HIG mills have been marketed, tested, sold and commissioned... Company Links www.outotec.com

Outotec is a leading manufacturer of thickening and clarifying solutions for the minerals industry. Our Outotec High Rate Thickener has pioneered thickening and clarifying methods worldwide. A number of significant thickening advances include: Low-profile triangular rake arms to decrease rake torque Outotec Directional Autodil and Outotec Turbodil: the worlds first thickening systems to auto-dilute feed, which effectively optimises flocculant consumption and performance Outotec FrothBuster: a deaerator that reduce the amount of froth forming on the surface of thickeners, automatic de-scaling of thickener rakes, and the complete redesign of thickener drives to use low-cost, efficient epicyclic gearboxes Outotec Vane Feedwell: a major innovation in the thickening industry, it incorporates a cutting-edge design, and features interconnected upper and lower zones. Filters Outotec is a leading industrial filtration solutions provider with full after sales services for solid-liquid separation. Mining and metallurgy, chemical process, and related industries benefit from our high-efficiency process technologies, products, and solutions. Outotec Larox filtration technologies are based either on overpressure, including automatic vertical pressure filters, horizontal filter presses, and polishing filters, or on under-pressure, including horizontal vacuum belt filters, ceramic disc filters, and conventional vacuum disc and drum filters. Most of the products have served the markets for several decades and all are supported by Outotec services. Analyzers and automation Outotec is a leading supplier of intelligent instruments, sampling systems, and advanced process automation for mineral and metal processing industries. Among the most well-known Outotec products in this field are Outotec Courier on-stream XRF analyzers that enable the real-time assaying of slurry process streams of all types of mineral processing plants. Online particle size analysis by Outotec PSI, combined with advanced control enables optimum grind size with maximum throughput to be maintained regardless of variations in feed quality. The Outotec Proscon and Outotec ACT (Advanced Control Tools) are process control systems and optimizing solutions for unit processes and complete processing plants. The systems comprise design, implementation, maintenance, and all the necessary hardware and software. Press Releases Introducing a Webinar on Outotec HIGmill Technology for Fine and Ultrafine Grinding In the past seven years, Outotec HIG mills have been marketed, tested, sold and commissioned... Company Links www.outotec.com

A number of significant thickening advances include: Low-profile triangular rake arms to decrease rake torque Outotec Directional Autodil and Outotec Turbodil: the worlds first thickening systems to auto-dilute feed, which effectively optimises flocculant consumption and performance Outotec FrothBuster: a deaerator that reduce the amount of froth forming on the surface of thickeners, automatic de-scaling of thickener rakes, and the complete redesign of thickener drives to use low-cost, efficient epicyclic gearboxes Outotec Vane Feedwell: a major innovation in the thickening industry, it incorporates a cutting-edge design, and features interconnected upper and lower zones. Filters Outotec is a leading industrial filtration solutions provider with full after sales services for solid-liquid separation. Mining and metallurgy, chemical process, and related industries benefit from our high-efficiency process technologies, products, and solutions. Outotec Larox filtration technologies are based either on overpressure, including automatic vertical pressure filters, horizontal filter presses, and polishing filters, or on under-pressure, including horizontal vacuum belt filters, ceramic disc filters, and conventional vacuum disc and drum filters. Most of the products have served the markets for several decades and all are supported by Outotec services. Analyzers and automation Outotec is a leading supplier of intelligent instruments, sampling systems, and advanced process automation for mineral and metal processing industries. Among the most well-known Outotec products in this field are Outotec Courier on-stream XRF analyzers that enable the real-time assaying of slurry process streams of all types of mineral processing plants. Online particle size analysis by Outotec PSI, combined with advanced control enables optimum grind size with maximum throughput to be maintained regardless of variations in feed quality. The Outotec Proscon and Outotec ACT (Advanced Control Tools) are process control systems and optimizing solutions for unit processes and complete processing plants. The systems comprise design, implementation, maintenance, and all the necessary hardware and software. Press Releases Introducing a Webinar on Outotec HIGmill Technology for Fine and Ultrafine Grinding In the past seven years, Outotec HIG mills have been marketed, tested, sold and commissioned... Company Links www.outotec.com

Filters Outotec is a leading industrial filtration solutions provider with full after sales services for solid-liquid separation. Mining and metallurgy, chemical process, and related industries benefit from our high-efficiency process technologies, products, and solutions. Outotec Larox filtration technologies are based either on overpressure, including automatic vertical pressure filters, horizontal filter presses, and polishing filters, or on under-pressure, including horizontal vacuum belt filters, ceramic disc filters, and conventional vacuum disc and drum filters. Most of the products have served the markets for several decades and all are supported by Outotec services. Analyzers and automation Outotec is a leading supplier of intelligent instruments, sampling systems, and advanced process automation for mineral and metal processing industries. Among the most well-known Outotec products in this field are Outotec Courier on-stream XRF analyzers that enable the real-time assaying of slurry process streams of all types of mineral processing plants. Online particle size analysis by Outotec PSI, combined with advanced control enables optimum grind size with maximum throughput to be maintained regardless of variations in feed quality. The Outotec Proscon and Outotec ACT (Advanced Control Tools) are process control systems and optimizing solutions for unit processes and complete processing plants. The systems comprise design, implementation, maintenance, and all the necessary hardware and software. Press Releases Introducing a Webinar on Outotec HIGmill Technology for Fine and Ultrafine Grinding In the past seven years, Outotec HIG mills have been marketed, tested, sold and commissioned... Company Links www.outotec.com

Outotec is a leading industrial filtration solutions provider with full after sales services for solid-liquid separation. Mining and metallurgy, chemical process, and related industries benefit from our high-efficiency process technologies, products, and solutions. Outotec Larox filtration technologies are based either on overpressure, including automatic vertical pressure filters, horizontal filter presses, and polishing filters, or on under-pressure, including horizontal vacuum belt filters, ceramic disc filters, and conventional vacuum disc and drum filters. Most of the products have served the markets for several decades and all are supported by Outotec services. Analyzers and automation Outotec is a leading supplier of intelligent instruments, sampling systems, and advanced process automation for mineral and metal processing industries. Among the most well-known Outotec products in this field are Outotec Courier on-stream XRF analyzers that enable the real-time assaying of slurry process streams of all types of mineral processing plants. Online particle size analysis by Outotec PSI, combined with advanced control enables optimum grind size with maximum throughput to be maintained regardless of variations in feed quality. The Outotec Proscon and Outotec ACT (Advanced Control Tools) are process control systems and optimizing solutions for unit processes and complete processing plants. The systems comprise design, implementation, maintenance, and all the necessary hardware and software. Press Releases Introducing a Webinar on Outotec HIGmill Technology for Fine and Ultrafine Grinding In the past seven years, Outotec HIG mills have been marketed, tested, sold and commissioned... Company Links www.outotec.com

Outotec Larox filtration technologies are based either on overpressure, including automatic vertical pressure filters, horizontal filter presses, and polishing filters, or on under-pressure, including horizontal vacuum belt filters, ceramic disc filters, and conventional vacuum disc and drum filters. Most of the products have served the markets for several decades and all are supported by Outotec services. Analyzers and automation Outotec is a leading supplier of intelligent instruments, sampling systems, and advanced process automation for mineral and metal processing industries. Among the most well-known Outotec products in this field are Outotec Courier on-stream XRF analyzers that enable the real-time assaying of slurry process streams of all types of mineral processing plants. Online particle size analysis by Outotec PSI, combined with advanced control enables optimum grind size with maximum throughput to be maintained regardless of variations in feed quality. The Outotec Proscon and Outotec ACT (Advanced Control Tools) are process control systems and optimizing solutions for unit processes and complete processing plants. The systems comprise design, implementation, maintenance, and all the necessary hardware and software. Press Releases Introducing a Webinar on Outotec HIGmill Technology for Fine and Ultrafine Grinding In the past seven years, Outotec HIG mills have been marketed, tested, sold and commissioned... Company Links www.outotec.com

Analyzers and automation Outotec is a leading supplier of intelligent instruments, sampling systems, and advanced process automation for mineral and metal processing industries. Among the most well-known Outotec products in this field are Outotec Courier on-stream XRF analyzers that enable the real-time assaying of slurry process streams of all types of mineral processing plants. Online particle size analysis by Outotec PSI, combined with advanced control enables optimum grind size with maximum throughput to be maintained regardless of variations in feed quality. The Outotec Proscon and Outotec ACT (Advanced Control Tools) are process control systems and optimizing solutions for unit processes and complete processing plants. The systems comprise design, implementation, maintenance, and all the necessary hardware and software. Press Releases Introducing a Webinar on Outotec HIGmill Technology for Fine and Ultrafine Grinding In the past seven years, Outotec HIG mills have been marketed, tested, sold and commissioned... Company Links www.outotec.com

Outotec is a leading supplier of intelligent instruments, sampling systems, and advanced process automation for mineral and metal processing industries. Among the most well-known Outotec products in this field are Outotec Courier on-stream XRF analyzers that enable the real-time assaying of slurry process streams of all types of mineral processing plants. Online particle size analysis by Outotec PSI, combined with advanced control enables optimum grind size with maximum throughput to be maintained regardless of variations in feed quality. The Outotec Proscon and Outotec ACT (Advanced Control Tools) are process control systems and optimizing solutions for unit processes and complete processing plants. The systems comprise design, implementation, maintenance, and all the necessary hardware and software. Press Releases Introducing a Webinar on Outotec HIGmill Technology for Fine and Ultrafine Grinding In the past seven years, Outotec HIG mills have been marketed, tested, sold and commissioned... Company Links www.outotec.com

Online particle size analysis by Outotec PSI, combined with advanced control enables optimum grind size with maximum throughput to be maintained regardless of variations in feed quality. The Outotec Proscon and Outotec ACT (Advanced Control Tools) are process control systems and optimizing solutions for unit processes and complete processing plants. The systems comprise design, implementation, maintenance, and all the necessary hardware and software. Press Releases Introducing a Webinar on Outotec HIGmill Technology for Fine and Ultrafine Grinding In the past seven years, Outotec HIG mills have been marketed, tested, sold and commissioned... Company Links www.outotec.com

The Outotec Proscon and Outotec ACT (Advanced Control Tools) are process control systems and optimizing solutions for unit processes and complete processing plants. The systems comprise design, implementation, maintenance, and all the necessary hardware and software. Press Releases Introducing a Webinar on Outotec HIGmill Technology for Fine and Ultrafine Grinding In the past seven years, Outotec HIG mills have been marketed, tested, sold and commissioned... Company Links www.outotec.com

Bozshakol copper mine, owned and operated by Kazakhmys, is the largest single copper mine development in Kazakhstan in terms of volume and value, and one of the largest undeveloped copper deposits in the world.

The Lac Paul phosphate mine is located approximately 200km north of the city of Saguenay in the Saguenay-Lac-St-Jean region of Qubec, and approximately 650km north-east of Montreal, covering an area of more than 27,000ha (270km).

In the past seven years, Outotec HIG mills have been marketed, tested, sold and commissioned for a number of projects worldwide in a wide range of applications and mill sizes, including the worlds highest power regrind / fine grinding / stirred mills.

The Outotec Open Ended Discharge Grinding Mill (OED Mill) enables innovative and efficient high-capacity circuit designs through the removal of pulp lifters from the discharge arrangement, facilitating reductions in both CAPEX and OPEX.

Outotecs commitment to facilitating safe, reliable, and efficient mill relining continues with the release of the Outotec Mill Equipment Transporter (MET) and Outotec Tube Mill Reline Machine (Tube MRM). B

In grinding applications time is money, so fast start-up and high availability are top priorities. The new Outotec MH Series Grinding Mill range offers flexible and easily deployable solutions that are cost-effective and easy to operate and maintain.

Tailings dewatering and disposal is a challenge that every mining operation has to deal with. The Outotec 2nd Generation Paste Thickener is designed to maximize underflow density regardless of challenging mineralogy and tailings feed rate variation.

Outotec has been awarded a contract to design and deliver a mine paste backfill system to OZ Minerals' Prominent Hill mine. The contract price is 15 million and it has been booked into Outotec's 2019 second quarter order intake.

Outotec and Terrafame, a Finnish multi-metal company, have agreed on the delivery of pressure leaching and solvent extraction technologies for a battery chemicals plant to be built in Sotkamo, Finland.

We have combined our expertise in the development of leading tailings and water treatment technologies to develop three new pre-engineered plant products, each one with Outotec's proven and technologically advanced equipment at its heart.

Outotec has been awarded orders for the delivery of process equipment for a copper concentrator expansion in Chile. The contract value booked in Outotec's 2017 fourth quarter order intake is approximately 14m.

Outotec has won two new grinding technology orders, one from Boliden of Sweden and one from Kazzinc of Kazakhstan. These two contracts are worth over 30 million. Boliden has awarded Outotec a contract to supply a primary autogenous mill for Tara Mine's lead-zinc ore project in I

Outotec has been awarded a contract by Hellas Gold for the supply of a large technology package for Hellas Gold's copper-gold concentrator plant in Skouries in Northern Greece. The total contract value exceeds 30 million. Hellas Gold owns three major gold and base metal deposits

efficient and cleaning calcite ultrafine mill price

efficient and cleaning calcite ultrafine mill price

Calcite is a prevalence non-metallic mineral resource, with the development of scientific and technological level and the upgrading of milling process, the use of advanced calcite ultrafine milling machine can improve the quality of calcite powder and fineness, help calcite in broadening the market application area to a higher level. Guilin Hong Cheng specializing in the production of calcite ultrafine milling machine, to develop a reasonable program based on the actual production needs of customers, the price of products provided is reasonable with excellent product quality.

Speaking of ultrafine milling machine, Guilin Hong Cheng has a wealth of manufacturing experience and high-tech applications, calcite ultrafine milling machine is Hong Cheng innovation produced deep processing equipment Hong Cheng HCH1395 is China's calcium carbonate ultra-fine processing of new energy-saving equipment rewarded by China's calcium carbonate Association, is the ideal choice for processing calcite.

Calcite ultrafine milling machine is integration with roller, grinding, impact and other comprehensive mechanical crushing performance, large crushing ratio, high energy efficiency, negative pressure production, with high efficiency to increase the work environment, less dust spill, stable operation. The good product size, no large particles of pollution, product quality and stability, equipment from raw materials broken, transport, milling to the finished product collection, storage, and packaging, can be an independent and complete production system.

[Features]: Integration of rolling, grinding, impact and other comprehensive crushing performance, scientific and rational design, unique structure and innovation, especially the HCH1395 model reward by the China Calcium Carbonate Association certification as calcium carbonate energy-saving equipment in China, HCH2395 is currently China's largest ultrafine grinding mill.

[Focus areas]: Focus on gypsum, calcite, barite, fluorite, marble and other Mohs hardness below 7 and humidity less than 6% non-metallic mineral ultra-fine processing and grinding, the equipment with a number of countries patented technology, performance reached the national leading level.

Simply complete the form below, click submit, you will get the price list and a Hongcheng representative will contact you within one business day. Please also feel free to contact us by email or phone. ( * Denotes a required field).

Copyright 2004-2018 by Guilin Hongcheng Mining Equipment Manufacture Co. LTD All rights reserved Tel: |FAX: | E-mail: [email protected] | After-Sales-Service:+86-400-677-6963.

new heavy mineral spiral for recovery of ultrafine chromite | multotec

new heavy mineral spiral for recovery of ultrafine chromite | multotec

Spiral concentratorsare gravity separation units which are cost and energy efficient. They are widely used to treat various minerals such as coal, iron ore and chromite ore. Separation is based on the difference in the specific gravity of the compounds in the mineral ore. Low recoveries and mass yield are obtained when processing ultrafine chromite with conventional spirals. It has been seen that spiral concentrators are efficient between particle sizes of 45 m and 1000 m. Particles less than 45 m tend to be suspended in water and thus report to the tailings fraction on the spiral. When a significant amount of ultrafine particles below 45 m is present in the feed, the efficiency of the spiral deteriorates. This is why alternative processing methods, such as shacking tables and flotation, are used. Traditionally de-sliming using ahydrocycloneis recommended prior to spiral processing. This helps reduce the amount of ultrafine particles and enhances efficiency. However, this could result in losses of ultrafine chromite in the hydrocyclone overflow. The aim of the internal spiral development study is to evaluate the effect of geometrical change on the spiral concentrator on the processing of ultrafine South African chromite ore. The spiral was tested on the rougher application with an UG2 chromite ore. The particle size of the material was 100% passing 850 m and 60% passing 45% m. The change in geometry of the spiral showed an effect on mass yield and recovery. The spiral offers approximately 2% additional mass yield and recovery than the conventional spiral. Additional tests are underway to further improve the mass yields and recoveries. Testing is underway at Multotec to improve mass yields and recoveries

Separation is based on the difference in the specific gravity of the compounds in the mineral ore. Low recoveries and mass yield are obtained when processing ultrafine chromite with conventional spirals. It has been seen that spiral concentrators are efficient between particle sizes of 45 m and 1000 m. Particles less than 45 m tend to be suspended in water and thus report to the tailings fraction on the spiral. When a significant amount of ultrafine particles below 45 m is present in the feed, the efficiency of the spiral deteriorates. This is why alternative processing methods, such as shacking tables and flotation, are used.

Traditionally de-sliming using ahydrocycloneis recommended prior to spiral processing. This helps reduce the amount of ultrafine particles and enhances efficiency. However, this could result in losses of ultrafine chromite in the hydrocyclone overflow.

The aim of the internal spiral development study is to evaluate the effect of geometrical change on the spiral concentrator on the processing of ultrafine South African chromite ore. The spiral was tested on the rougher application with an UG2 chromite ore. The particle size of the material was 100% passing 850 m and 60% passing 45% m. The change in geometry of the spiral showed an effect on mass yield and recovery. The spiral offers approximately 2% additional mass yield and recovery than the conventional spiral. Additional tests are underway to further improve the mass yields and recoveries.

Get in Touch with Mechanic
Related Products
Recent Posts
  1. end mill grinder

  2. grinding mill buying online

  3. grinding mill in wellawatte

  4. los angeles efficient new mineral ultrafine mill

  5. raymond grinding mill manufacturers india

  6. quartz grinding machinery manufacturers in uttar pradesh

  7. raymonds grinding mill

  8. crushers mill for sale south africa

  9. taclk grinding machines

  10. raymond woolen mills ltd pitampura

  11. resources and equipment on a gold mine

  12. meknes economic environmental construction waste shaking table for sale

  13. puebla low price environmental gangue powder grinding mill price

  14. raymond queneau

  15. lami high quality new brick and tile classifier manufacturer

  16. specification of ball mill feed discharge 500 t h

  17. any vacancy in ktv oil mills

  18. malacca economic large copper mine sand washing machine price

  19. high quality rock stone crusher manufacturer in suwon city

  20. high frequency screen rooms