The VERTI-G cuttings dryer incorporates a high-speed vertical centrifuge that maximizes liquid-solid separation in large-volume processing. This mechanism makes the VERTI-G dryer one of the industrys best performing and most dependable cutting dryers. Available in both standard and compact configurations, the VERTI-G dryer gives operators a critical advantage in meeting increasingly stringent environmental regulations for offshore cuttings disposal.
Maintained by programmable logic control (PLC), the flow of cuttings into the VERTI-G dryer is continuously fed to optimize liquid-solids separation. Once cuttings are introduced into the dryers charge hopper, widely spaced, independently adjustable flights continuously direct cuttings to the screen surface. The flights are coated with tungsten carbide to reduce wear and ensure increased tolerance.
Flights within the VERTI-G dryer create a rolling action that promotes efficient separation and prevents screen plugging. Under high G forces created by the large cone diameter, liquid-solids separation occurs instantly as cuttings make contact with the finer-mesh, high-capacity centrifuge screen. The result is clean return fluid and dry solids discharge.
The VERTI-G cuttings dryer improves overall cost efficiency by recovering costly drilling fluid that is recovered from cuttings as well as whole mud lost from shaker failure and rig motion. Further, the VERTI-G cuttings dryer produces lower waste volumes by generating dryer solids in both oil- and synthetic-based drilling fluid systems. Reducing waste volume helps to significantly reduce disposal costs.
Routine flushing of the dryer system prevents solids buildup in the recovery area and minimizes shutdowns for cleaning. In addition, normal-wear parts are easily accessible from the top of the unit; belts are easily changed without removing the gear assembly. Interchangeable tungsten carbide rotor blades protect the rotor and gearbox from excessive erosion, minimizing main component failure and lowering maintenance cost.
Lost revenue due to equipment downtime is often a direct result of some type of contamination, whether from dirt, water, an incorrect lubricant or a combination of these. Oil analysis testing can identify these contaminants, but unless you are aware of the issues that can arise from them, it can be difficult to take the appropriate actions.
This article will review the most common contamination types, the oil analysis tests most likely to indicate them, normal test results when these contaminants are present, and recommended actions for correcting each problem.
Abrasives are the top problem-inducing contaminants because they tend to cause the most damage. They are more likely to be hard contaminants and be in sizes that are well within your clearance ranges. The most prevalent forms of abrasives are dust or dirt and product or process contamination. If there is a process that includes any level of particulate, it is possible for this particulate to get into the lubricating system and cause damage no matter how soft the particle is.
Degradation from abrasive contamination comes primarily in the form of equipment wear, but another less widespread lubricant degradation problem can also occur. Abrasive wear or cutting wear is usually found in systems with a sliding motion load somewhere in the unit.
Commonly with thrust bearings or other softer metal bearings, the abrasive can wedge into the soft metal and gouge the harder steel surface. This is not to say that you cant have copper-alloy cutting wear. The metal produced depends on the contact surfaces in the path of the abrasive contamination and the hardness of the contaminant.
Systems with rolling actions such as rolling-element bearings, gear teeth, etc., are more likely to have pitting from abrasive contamination. As particulates roll through the load zone, the extreme pressure exerted on the contact point between the races and the rolling elements can pit the surfaces, forming cracks and initiating fatigue wear and spalling.
While lubricant degradation usually comes from another source, you may see some lost lubricant life from abrasive contamination. When a unit is wearing, the metal released by the abrasives can become a catalyst, and these particles increase the available surface area on which lubricants can form degradation byproducts.
Identifying abrasive contamination and wear is generally done through metals testing. If oil analysis is performed, what you typically will see with plain abrasive/dirt contamination is an elevation of the metals that are in direct contact with the abrasives. In gears, this will tend to be high iron levels with low alloy metals (chrome, nickel, manganese, etc.) and an increase in silicon and possibly aluminum if there is enough contamination.
Particle counting is another common test used to monitor contamination. However, keep in mind that a particle count is not selective in the particulate it is counting. Additional testing will be needed to determine the type of contaminant (water, air, dirt, fibers, metals, etc.).
Typical recommendations will include repairing the ingression point and filtering the lubricant, which are not always feasible. The protection of the equipment should be the analysts first and foremost concern when making recommendations. If filtration is not an option, changing the lubricant may be suggested. This is not as optimal as filtration, but when you have contamination, it is likely that the new lubricant will be much cleaner than the lubricant in the sump and can in effect dilute the problem contaminant, reducing the abrasive wear.
Some type of exception testing may also be recommended. This will depend on whether there is obvious wear in the system. Analytical ferrography or filter patch analysis can help determine the extent of the damage and if you need to take immediate action.
Dissolved water is usually benign except in extreme cases that require exceptionally low moisture levels. This form of water generally enters the lubricant via humidity or a similar process. The lubricant simply absorbs the water up to the saturation point and does not exhibit any signs of water contamination such as clouding.
Emulsified water is the most damaging form of water contamination. It occurs when the amount of water is beyond the saturation point and has likely entered the lubricating stream. A mixing action in the equipment may have emulsified the water, or it may be a function of a lubricant additive. Regardless, the initial identifier of this type of water contamination is that the lubricant is usually cloudy. This cloudiness comes from the water becoming small droplets within the oil. Emulsified water is the most damaging because it is free flowing with all of the lubricant and will be in the load zone.
Free water is somewhat less damaging than emulsified water but is still problematic. Some lubricants will not hold water in suspension past the saturation point, so it falls to the bottom of the sump. Among the problems resulting from this type of contamination include allowing water to become part of the lubricating stream, impacting the lubricants ability to shed water (demulsibility) and letting it emulsify, initiating biological contamination that will further degrade the oil, and plugging the filter. There is also the possibility of a safety hazard if free water is allowed to continue to enter the sump and overflow it.
With water contamination, there is just as much if not more damage to the lubricant as there is to the equipment. The main source of equipment degradation will be rust. Any time you have a degraded lubricant with water contamination, there is the possibility of rust on nearly any iron/steel surface. Rust is very hard (harder than steel) and creates abrasive particles in addition to the existing water problem.
Another problem with water contamination involves hydrogen embrittlement. In this phenomenon, water is cracked into oxygen and hydrogen, and the hydrogen is absorbed into metal surfaces. This creates a harder but more brittle surface that is unable to flex as needed for rolling elements to work properly. This results in cracking of the rolling surfaces and spalling.
In regards to lubricant degradation, the primary issue is having water in the equipments load zone. Water in a load zone is incapable of supporting a load, so the load continuously collapses onto a much thinner lubricant film. This allows significant surface-to-surface contact, which leads to wear.
Water contamination will also cause premature aging of the lubricant. It is estimated that water in a lubricant can reduce the lubricants lifespan by one-tenth. In addition, water in a lubricant sump can produce sludge. This is primarily a factor of simple premature aging of the lubricant but should be considered because it can give rise to a number of other issues such as thickening of the lubricants viscosity, preventing splash lubrication or plugging a filter.
Water usually does not enter a lubricating system by itself. External machine surfaces tend to be dirty, and the water will suspend this dirt and then enter the system with it. This not only causes water damage to the lubricant but also abrasive damage to the equipment.
In many cases, water contamination can be identified onsite with a visual test, as emulsified water in oil will become milky. However, air entrainment is another potential issue with cloudy oil, so you should go beyond just a visual test.
The hot-plate crackle test can also be used to check for water onsite as well as at most commercial laboratories. You can perform a go/no-go test by simply raising the hot-plate temperature to 320 degrees F and seeing if the sample sizzles like bacon when you put it on the surface. Of course, this should be done with caution, since hot liquid can spatter if there is a lot of water. Other methods are also available, but the hot plate provides a good initial detection for general-purpose analysis.
For a more exact measurement or to detect water at very low levels, have a Karl Fischer water test done. There are multiple variations of this test, including coulometric and volumetric, but they all have similar capabilities. Check to see which is being performed and if it will meet your needs. Coulometric tends to be more accurate at lower levels, while volumetric is usually better at higher levels. Certain additives, such as those that contain sulfur, can interfere with this type of test and should be taken into account.
Typical oil analysis recommendations include correcting the source of water. This should be done before any further action is taken. In some applications, water must be removed continually, and the water ingression cannot be prevented.
The next most common recommendation is to change the lubricant. This may be suggested in conjunction with other water-removal options (water drain-off, dehydration, centrifuge, etc.), depending on the labs knowledge of the sump size and the sites capabilities.
With a mineral oil in a glycol-based sump, you tend to see increased viscosity and sludge formation due to the chemical reaction between the hydrocarbon and glycol products. Once this chemical reaction begins, you may notice excessive wear, as the lubricant viscosity is excessively high. Since the two lubricants do not typically mix, you may also observe elevated wear because the load-zone lubricant film will not be a single lubricant and could have a reduced load-carrying capability. Significantly reduced lubricant life is also likely to result.
Because of the increased viscosity and sludge formation, you may have slow-flowing or even plugged filters. Acid formation as a degradation byproduct can also increase and attack the lubricated surfaces.
Viscosity testing and metals analysis are the primary methods used to identify a mineral oil in a glycol-based sump. Information about the lubricant in use will be required by the analyst to properly interpret the results.
If a mineral/glycol contamination issue is discovered, the likely recommendation would be to flush the sump. There is no other filtration option for a lubricant contaminated in this manner, so the contamination must be physically removed.
Please note that while the latest glycols derived from butylene are far more compatible with mineral oils than those using propylene and ethylene, the analysis of these new glycols is still evolving. This should be taken into consideration when evaluating oil analysis data from a glycol-based lubricant system.
Missing or wrong additives can lead to many potential problems. It is common to see a missing extreme-pressure (EP) or anti-wear (AW) additive in gear, bearing and hydraulic applications. If you are missing one of these additives and the equipment requires it, excessive rubbing wear and severe sliding wear could occur, depending on the tolerances and workload. These additives physically separate the loaded surfaces when the lubricant viscosity is insufficient, and without them you will be contacting these loaded surfaces.
If a lubricant with a detergency additive is put into a system designed to shed water, the detergency additive will ruin this shedding property of the lubricant. Generally, the only solution is to remove and completely replace the lubricant or risk having water ingression cause significant bearing wear. This problem is most common when dealing with large turbine sumps that have been contaminated with diesel engine oil. Consider that as little as a quart of diesel engine oil can destroy the demulsibility of 2,000 gallons of turbine oil.
If a system with yellow metal (copper alloys) has a manufacturers recommendation to not use an EP additive, this is usually because the EP additive would be highly corrosive to the yellow metals when the additive reaches activation temperatures. In these instances, a metals test should be conducted to reveal the problem. This test can detect additives and allow you to see changes in the additive levels. Oxidation or nitration tests may also be helpful.
In addition, you may be able to identify an incorrect additive with an infrared spectrum comparison/overlay. With this test, two lubricants can be overlaid on a single graph to determine if there are any chemical signature differences in the infrared signal. This is not a typical test and should be viewed as an exception test in most cases.
For these types of issues, the common recommendations will include using exception testing (analytical ferrography, etc.), which can reveal the extent of surface degradation if there are wear problems. Another recommendation would be to check the manufacturers specifications as well as the operating temperatures and how they relate to the lubricant selection.
The more widespread issue with an incorrect lubricant involves using the wrong viscosity. If the viscosity is too high, you may see increased wear in gear systems due to reduced or no splashing ability (if the system requires splash lubrication). In hydraulics, a high viscosity can lead to slow performance and low filtration rates. In nearly all low-viscosity situations, the result will be elevated wear. This is because the fluid film is not thick enough to prevent surface-to-surface contact during operation.
To detect a viscosity problem, perform a viscosity test. Also, consider conducting a baseline test on the new lubricant, as viscosities can change from batch to batch, and a lubricant top-up using a similar lubricant with a different viscosity may not be readily apparent. In addition, you may be able to identify this issue with metals testing, since additive levels will commonly fluctuate along with a viscosity change, even within the same product line.
The recommendations for viscosity problems can be fairly involved. This is because along with the possibility of having put a lubricant with the wrong viscosity into a machine, there may have also been an operating change that has affected the machine and caused the issue. For example, if the ambient temperature has increased, the viscosity may now be too low for the operating temperature, and wear may start to occur.
Outside of this possibility, the most common recommendation will be to change the oil in the sump. If the sump size is significant, it may be suggested to sweeten the oil or drain off a portion and replace it with fresh lubricant to improve the viscosity.
Please keep in mind that these are only a small portion of the problems that may arise and that laboratory testing capabilities are an ever-changing field. New technologies and improved methods are constantly becoming available. If you have a specific issue that requires testing, contact your oil analysis lab and be sure to get the best, most effective testing you can find.
Oil and gas refiningrelies on the purity of feed streams for efficient process reactions. Removal of fluid and particulate contaminants from feed streams and fluid recirculation processes is essential for improving downstream refining efficiency. Our advanced filtration solutions deliver premium filtration and fluid separation performance for a variety of refining applications such asalkylation,caustic treatment, hydroprocessing final proucts, HF, amine and catalyst recirculation systems, fluid separations and much more. As the industry leader in innovative filtration technology, we offer premium filtration solutions for downstream refining applications that maximize contaminant removal, minimize maintenance downtime, andextend the life of capital equipmentfor dramatically improved business performance.
Efficient filtration is essential for improving the performance of refining oil processes. Whether it be hydrocarbon feedstocks or supporting fluid systems such as solvents or catalysts, fluid streams that are free of contaminants facilitate efficient reactions and improve output quality.
With advanced media designs and materials, our filtration solutions maximize the capture of contaminants that are not only harmful to the immediate process, but can damage equipment further downstream resulting in lengthy and costly maintenance interventions. Along with increased capacities, the frequency of filter maintenance activities is significantly reduced to further reduce operating costs. For fluid recycle streams, our high performance filtration extends the life of costly fluids such as solvents and catalysts as well.
Ourdownstreamrefinery filtrationand separationproducts are specifically engineered to maximize contaminant removal and operate with longer onstream life for a truly streamlined operation that directly and positively impact business performance.
In todays business environment, refinery process efficiency is as important as ever. Minimizing downtime, improving process reactions and output products, and reducing operating costs are essential to optimizing business performance. Effective and reliable filtration solutions have direct and significant impacts on each of these concerns. As the global leader in innovative filtration technologies, we understand the pain points of the refining operation and has developed premium filtration solution to improve performance across numerous refining processes.
Throughout the downstream refining operation, both scheduled and unscheduled maintenance activities are major contributors to operational downtime. Regardless of the process, whether it be alkylation, caustic treatment, feedstock filtration, or anything else, contamination poses significant risks that can result in extensive and costly downtime. With our filtration solutions, contaminant removal is maximized which greatly reduces the risk of equipment failure and unscheduled maintenance interventions. Furthermore, with longer onstream life, the frequency of scheduled maintenance operations is reduced.
The purity of feedstocks and supporting fluid streams such as solvents and catalysts are essential to producing high quality end products. Our effective and reliable filtration and separation technologies remove harmful contaminants and facilitate efficient refining reaction that improve end-product quality and minimize product waste.
Our advanced filtration solutions are engineered to improve the downstream refining process through effective and reliable contaminant removal, reduced maintenance downtime, extended life of capital equipment, and enhanced end-product quality for a truly streamlined operation and significantly increased business performance. Contact our team of filtration experts to learn more about Palls innovative high performance filtration solutions for oil refinery applications.
Throughout the refining operation, both scheduled and unscheduled maintenance activities are major contributors to operational downtime. Regardless of the process, whether it bealkylation, caustic treatment, feedstock filtration, or anything else, contamination poses significant risks that can result in extensive and costly downtime. With our filtration solutions, contaminant removal is maximized with greatly reduces the risk of equipment failure and unscheduled maintenance interventions. Furthermore, with longer Donstream life, the frequency of scheduled maintenance operations is reduced.
Hydraulic fracturing is used in the oil and gas industry to increase the flow of oil and/or gas from a well. The producing formation is fractured open using hydraulic pressure and then proppants (propping agents) are pumped into the oil well with fracturing fluid to hold the fissures open so that the natural gas or crude oil can flow up the well. The proppant size, shape, and mechanical strength influences the integrity of the newly created fractures, and therefore the flow of oil and gas out of the well.
The material used for proppants can range from naturally occurring sand grains called frac sand (top left), resin coated sand (top right), to high-strength ceramic materials (bottom left), and resin coated ceramic materials (bottom right).
The quality control of the proppants is described mainly in ISO 13503-2 (1), which replaces the earlier API standards RP 56, 58 and 60. Among other tests, the standards demand the test of size, shape and crush resistance.
The size range of the proppant is very important. Typical proppant sizes are generally between 8 and 140 mesh (106 m - 2.36 mm), for example 16-30 mesh (600 m 1180 m), 20-40 mesh (420 m - 840 m), 30-50 mesh (300 m 600 m), 40-70 mesh (212 m - 420 m) or 70-140 mesh (106 m - 212 m). When describing frac sand, the product is frequently referred to as simply the sieve cut, i.e. 20/40 sand.
The shape of the proppant is important because shape and size influence the final permeability through the fracture. A wide range of particle sizes and shapes will lead to a tight packing arrangement, reducing permeability/conductivity. A controlled range of sizes and preferential spherical shape will lead to greater conductivity. The roundness has been historically analyzed (2) using a visual, manual method based on the chart shown in the figure below, originally developed by Krumbein and Sloss. This method results in large subjective differences from operator to operator.
In downstream oil and gas operations, separation of the various crude fractions is done for the purpose of purification or commercialization. The separation process involves removing several liquids and gases from the hydrocarbon mix in separation units. Some examples include gas-oil, fuel-gas, and water-gas separation. A piece of vital equipment used for this purpose is the coalescer.
A coalescer is a piece of industrial equipment used in the oil and gas processing and petrochemical industries to perform coalescence. Coalescence is the process of causing an agglomeration (coming together) of liquid aerosols to form larger droplets which are large enough to be drained away gravitationally. A coalescer operates in reverse to an emulsifier which creates emulsions.
A coalescer may be used on its own, or as a component of a larger separation unit. Selecting the right type of equipment will depend on the nature of the substance to be separated. For example, an oil coalescer or fuel coalescer can be used to recover oil or fuel from a water-oil mix respectively while a gas coalescer is used to separate gases from gas-fuel or gas-water emulsions.
Coalescers are widely used in downstream oil and gas operations and petrochemical industries for liquid-liquid or liquid-gas separation during product refining processes. For example, liquid-gas coalescers are used in the downstream sector to separate water vapor and liquid hydrocarbons from natural gas streams to ensure high product purity.
In addition, coalescers can be used to protect refining equipment from corrosion. In the petrochemical industry, coalescers as part of filtration systems to eliminate water vapor from products prior to storage.
There are two basic types of coalescers used in the industry, based on the mode of operation; electrostatic and mechanical coalescers. The mechanical coalescer is the predominant type utilized in the oil and gas industry and petrochemical plants all over the world.
Electrostatic coalescers utilize electric charges (DC or AC, or a combination of both) to induce coalescence of liquid molecules onto the surface of a collection tank. They are especially useful in water-hydrocarbon emulsions and widely used in offshore production platforms. The electrostatic charges help to destabilize the emulsion by increasing the size of the molecules, causing them to fall to the bottom of the tank.
Mechanical coalescers utilize a series of baffle walls or coalescing filters to separate water/hydrocarbon condensate from emulsions and coalesce them into larger molecules. A common application is for water separation from liquid hydrocarbons or natural gas.
Typically, the separating mechanism consists of a series of baffle walls or filters located at various points of the system. The system is designed such that the separation devices trap the various components of the mixture at intervals.
In the case of water-oil separation, baffle fibers separate the denser oil molecules and allow water molecules to diffuse and coalesce at a collection point underneath the baffle walls where they can be drained mechanically.
A coalescing filter is a device used to separate vapors, liquids, soluble particles, or oil from some other fluid through a coalescing effect. The coalescing effect is the coming together of liquid aerosols to form a larger whole which is easier to filter out of the system due to increased weight.
The filter consists of several progressive layers which perform specific functions; from separating solid particles to liquid molecules from a gas flow. Some common materials used as coalescing filters include borosilicate microfibers and semi-permeable membranes. A coalescing filter for natural gas separates water vapor and other particulates to improve product purity.
Integrated Flow Solutions specializes in the design and fabrication of modular, engineered to order process systems for the oil and gas industry. We offer a range of modular fluid filtration and fuel gas conditioning systems to meet the most stringent requirements for product purity.
Scientific progress in the last two centuries has allowed a great development of industrial production activities, modifying the relationship between mankind and the environment. In particular, the exploitation of natural resources has led to changes in the environment, often irreversibly. This raises the need to develop, in parallel to the new technologies, research aimed on the one hand at preventing potential ecological disasters, the other at remedying in case of contamination. In this frame, great are the efforts by developed countries to stimulate applied research for the rehabilitation of polluted sites.
One of the industrial sectors with the largest impact on the environment relates to the Oil and Gas industry. Pollution is due to several activities, including drilling, stimulation and the separation and dehydration operations. Two couples of categories can be individuated in the first place: pollution from punctual of diffuse sources and from chronic or accidental release of pollutants. From the pollutant point of view, this can be either organic or inorganic with, consequently, different environmental fates and repercussion on air, soil and groundwater.
The main categories of chemical standards for developing soil remediation guidelines are represented by: inorganic parameters, metals, hydrocarbons, halogenated aliphatics, pesticides, other organics and radionuclides. Both before and after the remediation is necessary to perform some important procedures. The first concerns monitoring and planning methods of remediation, where chemical, hydrogeological and microbiological analysis are made to characterize the soil and the pollution typology. The individuation of standards depends both on human and ecological features (as the use of land and water) as well as the kind of the contaminated matrix (physic-chemical characteristics). The second concerns the methods effectiveness control: the treatment is complete when the remedial target levels have been achieved for the specified use of the soils and the risk to the ecosystem is minimized. The number of samples to collect should be adequate to provide a statistically reliable result and strictly depends on the use of the soils and the possible contaminants migration. During the decontamination procedure, any possible impact on the related matrixes (such as air in case of VOC emission) should be constantly monitored. The Soil Screening Guidance is an EPA tool for the standardization of the step-by-step evaluation and clean-up of contaminated soils destined to possible residential use of land. In the following, main techniques for soil remediation will be presented focusing on the cleaning up after hydrocarbon contamination.
The goal of remediation is to remove, or to make harmless, substances contaminating the soil or groundwater. The remediation processes can be applied directly to the site of contamination, in situ, or after removing the contaminated soil, ex situ. Among the latter, there are the treatments on site, when working on the excavation site or off site, when you need to transport in plants located elsewhere. It is possible a classification of the different processes in accordance with the mechanism for cleaning up: non-organic (chemical, physical or thermal) or biological. The choice of different types of treatment is linked to several factors related to the nature of the pollutant, the polluted site, the type of technology (basically to its efficiency and cost). Briefly, the main techniques of both non-biological and biological remediation will be described below.
Description: this technique, generally carried out on site, consists in the soil decontamination by washing with water and possible addition of other substances (chelating agents, surfactants, acids or bases), according to the needs, in order to improve the solid-liquid extraction in contact with the ground. The latter undergoes an initial pre-treatment to remove coarse material and then switch to the washing stage where there is the process of extraction-solubilisation of the pollutant, which passes into the aqueous solution. Subsequently it has a solid-liquid separation that provides the clean solid and starts the water to the treatment thanks to which the pollutant is separated, concentrated, and recirculates the process water for the next wash. The capacity of reclamation is quite high (about 25 t / h). The duration of treatment Soil Washing is usually short, from one to three months and increases as the percentage of clay and silt content in the soil.
Development and applicability: currently, it is developed on a large scale and found more applications in Europe than in America especially in the removal of heavy metals. It can be applied, however, to a wide range of pollutants, including hydrocarbons and pesticides.
Critical issues: May be limited by silty and clayey soils that make it more difficult to solid-liquid separation. Physical separation is generally not effective for treating the chemically adsorbed metals.
Description: technique operating on site using a solvent to improve the efficiency of extraction, in a process very similar to that previously described. Since traces of solvent may remain in the ground at the end of the treatment, a criterion for its choice concerns the degree of toxicity.
Development and applicability: the solvent extraction has proven effective in removing a wide range of organic pollutants, from hydrocarbons to organochlorine pesticides, VOCs and petroleum wastes. The plants in full scale come to treat 20 t / h of soil.
Critical issues: It is not applicable for the removal of inorganic pollutants and some processes are limited by the solid matrix moisture content and fine particles. The presence of detergents and emulsifiers can unfavourably influence the extraction performance.
Description: this technique, also called Soil Vacuum Extraction, is applied in situ and used in the reclamation of the unsaturated zone of the soil, the area in which the pores of the soil contain air or water at a pressure lower than the atmospheric one (by capillarity). Using a system of wells, vacuum is applied so as to induce a controlled flow of air from outside which brings with it the volatile compounds and some semivolatiles. This system comprises a gas treatment extracts made from activated carbon filters, systems of incineration or cold traps; the treated gas is released into the atmosphere or re-injected into the ground.
Development and applicability: This method finds application mainly in soils at medium depth and permeability to avoid the short-circuiting of the steam flow or a difficulty in its circulation. The pollutants to be removed must have a vapor pressure greater than 1 mm Hg at 20C. Both SVE and air sparging are used to clean up several acres of contaminated soil and groundwater at the Vienna PCE Superfund site in West Virginia.
Description: technology operating in situ in which air is bubbled through a contaminated aquifer. The air bubbles cause stripping of volatile organic compounds present in the saturated zone, the part of the subsurface in which the pores of the soil are filled with water at pressure equal to or greater than the atmospheric one. In general, the exit gas from the underground are conveyed by means of a suction system, which often coincides with a SVE inserted into the unsaturated zone.
Critical issues: if it is not used in conjunction with SVE, an unwanted migration of pollutants outside the contaminated area may occur. Special attention should be given in the event of large doses of pollutant supernatants (eg. Hydrocarbons in suspension), to prevent the push and the bubbling cause aerosols in the surrounding areas.
Description: this technology allows the in situ simultaneous removal of the contaminants present in the unsaturated zone and the saturated zone of the soil (In case the contamination concerns both stages) by the means of a vacuum pump. In this way extends the applicability of the SVE to the saturated zone of the soil. Downstream of the vacuum pump it is necessary to separate the liquid from the vapour phase and proceed to the train of treatments for the different phases.
Development and applicability: suitable for this technology are the low permeability soils, usually clay, in which the cone of depression extends in depth, going to increase the thickness of the unsaturated zone. An important factor to consider concerns the hydrogeology of the site, crucial to understand the degree of applicability and effectiveness of this treatment.
Description: in the solidification processes, the pollutants are physically linked, or trapped in a solid matrix, while in the stabilization, chemical reactions transforming the pollutant in a less mobile species, are favoured. An example is given by the cement that immobilizes many metal contaminants by forming insoluble hydroxides, carbonates and silicates (stabilization) as well as providing an encapsulating matrix for the leaching attenuation (solidification).
Development and applicability: this technique is used mainly for the treatment of inorganic pollutants, including radionuclides, while the presence of organic material may constitute an obstacle for the success of the neutralizing process.
Description: This ex-situ treatment consists in the desorption of volatile pollutants through the supply of heat from outside. The material polluted, is sent to a rotary kiln or to a heated auger system, where, by increasing the temperature the formation of gases and vapours of polluting compounds is guaranteed. The contaminants destruction is realised using a secondary treatment units.
Development and applicability: there are two processes in response to operating temperature, low (90-320C) and high (320-560C). In the first case, generally suitable for non-halogenated hydrocarbons, no thermal oxidation occurs and the physical characteristics of the soil remain unchanged. In the second case, instead, semivolatile organic compounds, volatile metals and polycyclic aromatic compounds are removed by operating, often in combination with the incineration processes, solidification/stabilization and dechlorination.
Description: technology that works off site used for the final disposal of contaminated materials resulting from the treatment of soil washing, solvent extraction and thermal desorption. The contaminated material is fed into a burner where takes place the volatilization and oxidation of organic compounds at temperatures between 870C and 1200C, in the presence of oxygen. Often it is necessary to supply the burner with an auxiliary fuel, both to trigger and to maintain the combustion.
Development and applicability: used especially if contamination concerns explosives, chlorinated hydrocarbons, polychlorinated biphenyls and dioxins. In the presence of heavy metals, it is necessary to inert ashes.
Description: technology operating in situ, for the soils treatment in the unsaturated zone. It stimulates the degrading action of microorganisms already present in the soil (native microbial flora), providing oxygen and, where necessary, mineral nutrients into the ground by percolation or by direct input with specific spargers. Oxygen is normally provided through direct input or air suction through spears stuck in the ground.
Development and applicability: it is useful in the remediation of hydrocarbons contaminated soils and is adaptable to soils with high permeability. Process often coupled with SVE: first making an SVE with the removal of the more volatile hydrocarbons, then performs a bioventing, simply by reducing the air flow and injecting nutrients for degrading residual non-volatile hydrocarbon components.
Description: technology similar to bioventing, which operates in situ for the treatment of saturated soils and groundwater. The acceleration of the native microbial flora degradation is done through direct air and appropriate nutrients entering the contaminated area.
Development and applicability: it is normally used to degrade the contaminants that are dissolved in the groundwater, adsorbed on soil particles below the groundwater level or in the capillary fringe area. Effective is the application in petroleum products reduction, usually realised for underground storage tank sites.
Description: in this way is performed an intrinsic bioremediation, exploiting the nature ability to restore a polluted environment. Set up a site for a natural attenuation essentially means: run a targeted monitoring to know the precise boundary between the contaminated area and the clean zone, a campaign of analysis for the measurement of some basic parameters (temperature, pH, redox potential, concentration nitrate, nitrite and ammonia, phosphates) and enumeration of bacterial populations specific for the different types of biodegradation.
Critical issues: the presence of non-biodegradable pollutants, existence of contamination phenomena able to convey hazardous substances towards targets of environmental interest and need to complete the remediation in a short time.
Description: technique operating on site which consists of arranging the contaminated material on a non-permeable surface in a layer normally less than one meter, ensuring, during the decontamination period, the maintenance of the best conditions for the microbial populations development. It is essential to ensure, from the beginning of the treatment, a correct balance of the main nutritional components of the system: carbon, nitrogen and phosphorus, in relations respectively 100: 5: 1 in addition to the content of water content (60-70% of the saturation value), and the soil pH, which must be neutral. Furthermore it is necessary to facilitate the air entry for the correct oxygen supply to the bacterial populations, generally by mixing the soil to be treated or by entering bulking agents (wood chips, expanded silicon, etc.). This process requires an extended time frame, possibly up to 24 months, depending on a number of factors, including the nature of the contamination, the concentrations of contaminants, types of soil and volume of soil to be remediated. Landfarming to remove volatile constituents from soils through evaporation, without biological degradation, is not acceptable, unless are realised the volatile constituents capture and treatments.
Description: technique very similar to landfarming, with the main difference residing in the method of oxygen transfer. In the preparation of the biopile soil layers are superimposed with interspersed perforated tubes, used to distribute, air and solutions containing the necessary nutrients. In the presence of volatile pollutants, the biopile can be covered with waterproof sheets with appropriate openings to let out the steam to be sent to treatment. The presence of the sheets also facilitates the monitoring of the parameters indicated in the landfarming section.
Description: technique consisting in the remediation of soil within fermentation reactors. Inside the reactors can be controlled effectively operating parameters or use non-native bacterial populations (bioaugmentation). Theoretically it would be possible to use genetically modified bacteria, practice today banned in open field.
Description: A system for the in situ treatment of groundwater. Inside the aquifer is placed transversally a barrier consisting of soil or suitable solid support colonized by microorganisms. Therefore the barrier is passive, and biodegradation occurs by contact between the water that runs through it and microorganisms adhering to it. It is also necessary to construct a series of wells for the air and nutrients intake for the present microorganisms.
In recent years, research in the field of bioremediation is evolving to try to increase the contamination cases resolved by biological remediation. In this regard two research lines are being developed to exploit synergistic actions respectively between microorganisms and plants (bioremediation/phytoremediation) and between bacteria and fungi. Not to be overlooked are the research of genetics to modify microorganisms and make them capable of degrading substance considered recalcitrant and the research to make possible actions in situ even in situations where it is very difficult to convey sufficient amount of oxygen. Have particular importance the cases of hydrogen or magnesium peroxides use .
In the non-bio field, permeable reactive barriers (continuous and non), characterized by high conductive reactive media capturing the contaminants by deviating the natural flows, are producing invigorated research results. Another interesting field of research can be individuated in the use of hydraulic fracture technology for soil and groundwater remediation. FRx promotes the Hydraulic fractures as an optimal in situ treatment for the removal of materials from extraction wells. They utilizes US EPA practices and individuates four key factors distinguishing the uses of hydraulic fractures for soil and groundwater remediation from those ideated for the oil and gas production: volume, depth pressure and chemical additives .
Our solids control technologies optimize drilling efficiencies by maintaining fluid integrity, reducing fluid losses, minimizing HSE impact, and lowering drilling costs through NPT management. Offerings include advanced shale shakers and associated OEM composite screens, new-generation centrifuges and pumps, cuttings dryers, and the RHE-USE two-stage centrifuge system enabling reuse of invert emulsion drilling fluids over multiple wells.
We work closely with rig designers, contractors, operators, and shipyards to customize integrated drilling and waste management configurations for optimal fluid recovery, reduced dilution rates, less waste generation, and lower costs.
New-generation cuttings management technologies reduce the HSE footprint of drilling operations. They include fully enclosed pneumatic technologies for the containment, handling, temporary storage, and transport of drill cuttings. Thermal and frictional desorption minimize the fluid content of cuttings, significantly reducing total waste volumes and the need for costly transportation. We also have significant expertise in planning, implementing, and monitoring in situ injection of drilling waste. Operators save time, labor, rig space, and mitigate HSE risk by avoiding transportation over water or on roadways.Get in Touch with Mechanic