Abstract: A system for providing improved bulk liquid mixing and effective gas-liquid contacting for mass transfer of the gas to the liquid, especially a non-Newtonian liquid, the viscosity of which decreases when under shearing conditions (shear thinning), in an upright tank. An upright draft tube is mounted within the tank and has a lower end spaced from the tank bottom and an upper end spaced below the surface of the liquid in the tank. A plurality of mixing impellers in the draft tube are sufficiently close to each other to establish a field or pattern of agitation to cause shear thinning and upflow throughout the draft tube and which produces significant turbulence at the liquid surface. A plurality of radially inwardly projecting, circumferentially spaced baffles extend from the draft tube and are proximate the mixing impellers to prevent swirling of the liquid within the draft tube.

Abstract: A recirculating composting apparatus cycles air and waste gases through a composting vessel, into a curing bin which contains previously composted material. Within the curing bin, ammonia and other noxious gases are adsorbed and converted into valuable fertilizer. The gases released from the curing bin may pass into another curing bin and then be recirculated back into the composting vessel, or may alternatively be released into the environment or passed through a biofilter. In preferred embodiments, like containers may be used for each curing phase and also the composting phase. The use of similar or compatible containers allows an entire vessel to be converted from a composting vessel into a curing bin simply by disconnection at one location and reconnection at a different location, without having to disturb the contents within the vessel or incur the undesired associated labor.

Abstract: A method and an apparatus for decomposing and eliminating ethanol in an exhaust gas by bringing the ethanol in the exhaust gas into contact with an ethanol-utilizing microorganism held in a filter bed are provided. A microorganism selected from the genus Candida, the genus Pichia and/or the genus Hansenula is used as the ethanol-utilizing microorganism, whereby a method and an apparatus having a high removal efficiency of ethanol in the exhaust gas, and being capable of long-term, stable decomposition and elimination of ethanol under high concentration, high load capacity, can be provided.

Abstract: It has been discovered that fluids viscosified with viscoelastic surfactants (VESs) may have their viscosities reduced (gels broken) by the direct or indirect action of a biochemical agent, such as bacteria, fungi, and/or enzymes. The biochemical agent may directly attack the VES itself, or some other component in the fluid that produces a by-product that then causes viscosity reduction. The biochemical agent may disaggregate or otherwise attack the micellar structure of the VES-gelled fluid. The biochemical agent may produce an enzyme that reduces viscosity by one of these mechanisms. A single biochemical agent may operate simultaneously by two different mechanisms, such as by degrading the VES directly, as well as another component, such as a glycol, the latter mechanism in turn producing a by-product (e.g. an alcohol) that causes viscosity reduction. Alternatively, two or more different biochemical agents may be used simultaneously.

Abstract: This process is unique in photosynthetic carbon sequestration. An on-site biological sequestration system directly decreases the concentration of carbon-containing compounds in the emissions of fossil generation units. In this process, photosynthetic microbes are attached to a growth surface arranged in a containment chamber that is lit by solar photons. A harvesting system ensures maximum organism growth and rate of CO2 uptake. Soluble carbon and nitrogen concentrations delivered to the cyanobacteria are enhanced, further increasing growth rate and carbon utilization.

Abstract: A process for treating hydrocarbon-containing effluents that comprise isoalkanes to reduce the hydrocarbon concentration at least partly is described, characterized in that in the presence of a suitable substrate, a Corynebacterium urealyticum CIP-I-2126 bacterium is grown, and the hydrocarbons that are contained in the effluents are degraded by the biomass of said bacteria that is thus produced. Application for pollution control of water and soil contaminated by hydrocarbons and optionally by ethers that come from a gasoline, kerosene and/or gas oil fraction.

Abstract: A biofilter reactor includes a housing, an axial pipe rotatably supported in the housing and including a plurality of perforations that open into the interior of the housing for collecting a treated fluid. The axial pipe includes an outlet in communication with the interior thereof for removing the treated fluid from the housing. A porous medium is disposed about the axial pipe and is rotatable therewith. The porous medium is made of a microbial foam.

Abstract: To provide a process for treating gas for decomposing organic solvent and/or other organic gas contained in exhaust gas effectively and simply at low costs to remove the decomposition product of organic gas by applying other process. The gas can be treated very effectively by decomposing or removing a target gas component dissolved in liquid capable of treating the gas, preferably, by applying microbial treatment, after bringing the gas rising into contact with the liquid falling in a gas treatment tower wherein part of the gas (branched gas ) is admixed with the liquid before feeding the liquid into the tower.

Abstract: A compact plant for the depuration of polluted air, in particular from odorous substances, comprising a unitary housing in which are placed, in sequence, a prescrubbing section, a filtering bed and a postscrubbing section, in the two scrubbing sections the air flowing counter currently with respect to the water sprayed by suitable nozzles and possibly added with suitable chemical additives, whereas the filtering bed, preferably consisting of particles of the kind described in EP-497214, is sprayed with water added with nutrient substances for the micro-organism present in the bed itself, the water being sprayed flowing co-currently with the air passing through the bed.

Abstract: The biological washing reactor and the wet electrofilter are located in a common container. This container ends at the bottom at a biotank. A droplets remover is located at the purified gas outlet. The exhaust gas which is to be purified and which contains impurities in form of aerosols, dust and organic gases flows through the exhaust gas inlet into the container and flows firstly through the preliminary separator and thereafter through a biological washing reactor and the wet electrofilter. The process water for the continuous sprinkling of the preliminary separator and of the biological washing reactor, and for the intermittent cleaning of the wet electrofilter and of the droplets remover is circulated in a closed loop via the biotank. The circulated process water is regenerated in the biotank.

Abstract: A method and apparatus are designed for converting waste gases from industrial processes such as oil refining, and carbon black, coke, ammonia, and methanol production, into useful products. The method includes introducing the waste gases into a bioreactor where they are fermented to various products, such as organic acids, alcohols, hydrogen, single cell protein, and salts of organic acids by anaerobic bacteria within the bioreactor. These valuable end products are then recovered, separated and purified.

Abstract: A system for providing improved bulk liquid mixing and effective gas-liquid contacting for mass transfer of the gas to the liquid, especially a non-Newtonian liquid, the viscosity of which decreases when under shearing conditions (shear thinning), in an upright tank. A process, such as fermentation which produces commercial quantities of polysaccharides such as xanthan gum. may be carried out in the tank. An upright draft tube is mounted within the tank and has a lower end spaced from the tank bottom and an upper end spaced below the surface of the liquid in the tank. A plurality of mixing impellers in the draft tube are sufficiently close to each other to establish a field or pattern of agitation to cause shear thinning and upflow throughout the draft tube and which may produce turbulence at the liquid surface. A plurality of radially inwardly projecting. circumferentially spaced baffles extend from the draft tube and are proximate the mixing impellers to prevent swirling of the liquid within the draft tube.

Abstract: A counterflow scrubbing system for deodorizing air having sulfur components such as H2S typically associated with wastewater treatment includes a tower vessel having sulfer-oxidizing microorganisms in porous rock media, and operates at a pH preferably between 1.5 and 4.0 The media has a high ratio of surface area to volume, being at least 1000 and preferably approximately 10,000. The system can operate continuously without requiring objectionable chemicals, relaying of filter beds, or back-flushing. Optionally, concentrations of nutrients and/or bacteria are added to make-up water from an included reservoir.

Abstract: The invention relates to a method for biological cleaning of a contaminated gas flow containing gaseous and/or particulate contaminants comprising the steps of contacting the contaminated gas flow counter-currently with a jet of suitable microorganism-containing scrubbing liquid in order to enhance absorption of gaseous and particulate contaminants in the scrubbing liquid; recovering the scrubbing liquid in a vessel; draining part of the scrubbing liquid from the vessel and compensating the drained part with fresh liquid. The method is carried out in a reverse jet scrubber and does not use any packing material for support to the microorganisms.

Abstract: An integrated treatment process and apparatus is provided for removing selected contaminants from both liquid and gaseous waste streams. A multistage separation and bio-oxidation substrate is provided in a column through which the contaminants are passed. The substrate components provide absorption, adsorption, ion exchange, solubility, and bio-degradation qualities to the column to effectively separate and destroy a wide range of contaminants in industrial waste streams.

Abstract: A microbial consortium, ATCC 202177, is enriched to remove target sulfur compounds from gases in the presence of ammonia, cyanide, carbon monoxide, and other toxic gases and mixtures thereof. The ATCC 202177 consortium is cultured in an anaerobic or aerobic nutrient medium until enough cells of ATCC 202177 are recovered to remove the target sulfur species at a pressure ranging from 1 to 80 atmospheres.

Abstract: An odor treating system in which a silo-type structure (2) incorporates in layered sequence along its height at least one bioscrubber (4) and one wet scrubber (6) or biofilter and incorporates a port (10) for introducing malodorous effluent into the structure (2) below the scrubbers (4, 6) and fan means (1) overlying the scrubbers (4, 6) for drawing the effluent through the scrubbers (4, 6) to deodorize, dilute and disperse the effluent into the atmosphere.

Abstract: A hybrid filter system for degrading a sulfur-containing compound having a primary stage sacrificial filter and a secondary stage biofilter is disclosed. This hybrid filter system significantly increases the lifetime of the biofilter providing a cost effective and removal effective biofiltration filter system. The process consists of two filtration stages, a primary stage sacrificial filtration and a secondary stage biofiltration. A small percentage of the sulfur-containing compound is oxidized to elemental sulfur which blocks the pore space of the filter matrix. The primary stage sacrificial filter is used to trap and remove elemental sulfur which is produced when the sulfur-containing compound is passed through the filter. To protect the secondary stage biofilter from premature plugging by precipitated elemental sulfur the primary stage sacrificial filter is used to capture the precipitated elemental sulfur.

Abstract: The invention relates to a process of combatting micro-organisms in industrial processes, particularly in the wood processing industry, by adding glucose oxidase and optionally glucose or a source of glucose to the process solution or slurry.

Abstract: A system for deodorizing malodorous sewer gas having a tower with a lower gas inlet and an upper gas outlet, malodorous gas passing into the tower through the gas inlet. Packing is positioned within the tower between the inlet and outlet. An enzyme solution recirculating system withdraws enzyme solution from the interior bottom of the tower and introduces it into an upper portion of said tower, the enzyme solution passing downward through the packing. A blower moves malodorous gas into the tower inlet and upwardly through the packing for contacting downwardly passing enzyme solution. An enzyme solution replenishment system is connected to the circulation system.

Abstract: The need to filter gas emanating from a containment vessel is reduced or eliminated by maintaining, within the vessel, a gradient that concentrates most of the gaseous contaminants away from the vessel exits. This is achieved by reducing the density of gas drawn from the region near its source and discharging the reduced-density gas to another region of the vessel. Owing to its reduced density, the discharged gas already has a lower contaminant concentration than the source gas. The concentration decreases further as convection draws the discharged gas back to its source. So long as the gas flows within the containment vessel are non-turbulent, the concentration gradient remains substantially static, and the vents remain exposed only to low concentrations of contaminants. The gas density may be reduced by heating and humidification, catalytic reaction, or reaction among constituents of the gas.

Abstract: A process for the removal of sulphides, including hydrogen sulphide, carbonyl sulphide and carbon disulphide, from a gas stream by scrubbing the gas with an aqueous washing liquid and treating the washing liquid with sulphide-oxidizing bacteria in the presence of an electron acceptor and reusing the treated liquid as a washing liquid, wherein the scrubbing and the bacterial treatment are carried out in the same reactor and nitrate is used as the electron acceptor. The process is especially useful of desulphurising gas at high pressure, such as natural gas.

Abstract: A reaction purifier (100) using microorganisms which feed on harmful components in exhaust gas is installed in an exhaust passage (18, 21, 22, 23, 24) of an engine (1). The microorganisms are mixed with a culture fluid, and the culture fluid is circulated through tubes (111) in which micro holes (111A) are formed. The diameter of these holes is such as not to allow culture fluid to pass, but to allow exhaust gas to pass. The tubes (111) are housed in a casing (112), and harmful components are removed by leading exhaust gas into the casing (112) to bring into contact with the microorganisms in the culture fluid. By using the reaction purifier (100) and catalytic converter (20A, 20B) in conjunction, even better exhaust gas purifying performance is obtained.

Abstract: Degassing is accomplished by driving a gas-containing solution to a subatmospheric pressure approximately equal to the solution vapor pressure, and maintaining the subatmospheric pressure notwithstanding evolution of gas from the solution. This may be accomplished using a vacuum tower arrangment whereby a column of the gas-containing liquid is drawn to the maximum physically attainable height. So long as the vacuum is coupled to the liquid column above this height (generally on the order of 34 feet, depending on the ambient temperature and the composition of the liquid), the liquid will not be drawn into the vacuum, which creates a non-equilibrium region of extremely low pressure above the liquid that liberates dissolved gases. Moreover, liquid introduced into the low-pressure region above the column will fall onto the column without entering the vacuum system.

Abstract: Process for the microbiological clean up of halogenated ethenes, characterized in that bacterial strains which are growing with ethene as carbon and energy source and break down halogenated ethenes are preadapted with ethene as carbon and energy source for new formation and for energy supply and are contacted in an aerobic bioreactor with the halogenated ethenes to be cleaned up.

Abstract: A device for purifying gases, such as air in particular, or liquids, such as water in particular. The device comprises a chamber in which filter material is incorporated. The chamber has inlets and outlets for the medium to be purified. The medium is led through filter material, in which micro-organisms are employed for the purification. A mat having large open pores is used as filter material. The mat is manufactured from foamed plastic material having open pores and is flat on one side and is provided with extrusions on the other side. The material may be polyurethane. The mat is wound in such a way that it can be situated on a tube. The chamber has a substantially cylindrical shape into which the rolled-up mat can be fittingly slid.

Abstract: The invention relates to a water supply and drainage type microorganic deodorizing system, by which a clogging of deodorizer can be effectively prevented in order to decrease a deodorizing capacity, wherein deodorization chambers are provided in two stages in the tower main body, offensive odor constituents are gradually adsorbed by filters of the deodorization chambers as ordered by decomposing action of microorganisms, and decomposed in order to completely deodorize. Furthermore, by providing a water sprinkling system of replenishing water in relation to the filters the performance of the filters can be restored, and furthermore, by providing a water diluting system WC which dilutes cleansing water of the filters, drainage can be prevented from being contaminated, in accordance with drainage standards.

Abstract: A process for scrubbing a gas containing hydrogen sulphide and/or carbonyl sulphide, in which the spent scrubbing liquid is treated with autotrophic sulphide-oxidizing bacteria capable of oxidizing at high pH, and elemental sulphur is obtained, the elemental sulphur is separated and the treated scrubbing liquid is recycled to the gas scrubbing step. Before recycling, the scrubbing liquid may further be treated with heterotrophic thiosulphate-oxidizing bacteria which produce polythionate which is useful for further enhancing the sulphide-scrubbing capacity of the scrubbing liquid.

Abstract: A process for removing pollutants is enhanced by using a slurry containing a particulate adsorbent carrying a biologically active material. The pollutant is contacted with the slurry and is adsorbed and biodegraded therein. The slurry is useful in a bioscrubber and provides economical high flow rate treatment of gases.

Abstract: A system for removing particulate, sulfur dioxide, nitrogenous oxides and other condensables from the flue gas of a coal, lignite, or other solid fuel combustor. The system can combine biomass filtration, anaerobic digestion, steam absorption refrigeration, and heat exchangers to minimize parasitic energy consumption, solid and liquid waste disposal and interference with combustion efficiency, while achieving near total reduction of contaminants without regard to sulfur or ash content of fuel. Gases at the exit of a multiclone of a fuel-combustor enter a waste heat boiler, generating low pressure steam that drives a steam absorption chiller. The flue gas which still contains small particulate material pass through a moving belt system conveying a mat of chopped biomass that can be impregnated with bacteria that feed on nitrogenous oxides. The mat is sufficiently thick and moist to entrap the remaining solids and smoke in the exhaust stream.

Abstract: Apparatus for the purification of waste water and/or waste gas using a biofilter containing a filtering material, wherein the waste water move downwardly thereinto while the waste gas move upwardly or downwardly thereinto, is disclosed. Also disclosed is an apparatus for simultaneous purification of waste water and waste gas, comprising a filtering material comprised of a succession of layers. More conveniently, the apparatus comprises sufficient filtering material between the gas inlet and water outlet to ensure that the water coming out of the apparatus has not been substantially contaminated by the upwardly moving waste gas. In a preferred embodiment, the upper layer of filtering carrier material has a substantially lower filtration capacity than a lower layer of filtering carrier material, to prevent clogging of the filtering material upon downward flow of the waste water. Further disclosed is an apparatus for simultaneous purification of waste water as waste gas moving both downwardly.

Abstract: An odor control system consisting of a cylindrical bio-scrubber (20) packed with means providing an extensive surface area over which liquid media is caused to cascade, an oxidation pond (22) containing selected microorganism in a fluid media, and means (25) for introducing gases to be treated into the bio-scrubber (20) while concurrently causing microbial-impregnated fluid from the oxidation pond (22) to flow through and into contact with effluent gases passing through the bio-scrubber (20), thereby to effect transport of gases to the oxidation pond (22) where volatile organic compounds are metabolically destroyed. When necessary to achieve optimum odor reduction a further element can be added to the overall combination in the form of a biofilter (30) through which gases emanating from the bio-scrubber (30) are passed before their release to the atmosphere.

Abstract: A system for purifying a polluted air by using algae such as Spirulina is capable of reducing carbon dioxide (CO.sub.2), nitrogen oxide (NO.sub.x) and/or sulfur oxide (SO.sub.x) in the polluted air and generating oxygen. That is, this system comprises a culture tank filled with a culture fluid including the algae, an air supply unit for forcing the polluted air into the culture fluid to dissolve carbon dioxide and nitrogen oxide and/or sulfur oxide in the culture fluid, and a lighting unit for radiating a light to the culture fluid. By radiating the light to the culture fluid in the presence of carbon dioxide, photosynthesis of the algae is promoted to convert carbon dioxide into oxygen. In addition, the algae use the nitrogen oxide and/or sulfur oxide as a nutrient during the photosynthesis. As a result, the present system can efficiently purify the polluted air to generate a purified air, which is rich in oxygen.

Abstract: Process and device for so-called biofilters, in which polluted gas, e.g. air, is made to pass through, and thereby be cleaned in a bed of bed media arranged in a container, comprising measuring the moisture content of the bed and the supply of fluid, e.g. water, in order to maintain the desired moisture content, wherein the moisture content of the bed is measured by elements (9; 23, 23') which are not in contact with the bed media.

Abstract: A process is provided for removing hydrogen sulfide out of gas, such as gas separated from geothermal brine, by passing the hydrogen sulfide containing gas and oxygen containing gas through a bioreactor containing bacteria, such as Beggiatoa, Thiothrix and Thiobacilli, supported on a support so that the bacteria oxide the hydrogen sulfide into elemental sulfur, which is subsequently oxidized into sulfuric acid. The flow of the gases through the bioreactor is cyclically reserved about every 12 hours to about 5 days so as to provide a better sulfur distribution in the support, resulting in more efficient oxidation of the elemental sulfur into sulfuric acid. Hydrogen sulfide depleted gas and sulfuric acid are discharged from the bioreactor. A plurality of bioreactors may be used, connected in series or in parallel.

Abstract: An apparatus and method for control and treatment of ammonia (NH.sub.3), oxides of nitrogen (NO.sub.x) or volatile organic compounds (VOC) emitted in a gaseous form from various processes where these compounds are used, present or formed. The gaseous emissions may be comprised of NH.sub.3, NO.sub.x or VOC individually or as a mixture of these compounds and other gaseous substances such as air, organic vapors and other organic or inorganic gases. The control and treatment method involves simultaneous liquid scrubbing and biochemical decomposition of NH.sub.3, NO.sub.x or VOC or a combination thereof.

Abstract: A method for increasing biodegradation of sparingly soluble volatile organic compounds (VOCs) in a bioreactor is disclosed. The method comprises dissolving in the aqueous phase of the bioreactor a water soluble, nontoxic, non-biodegradable polymer having a molecular weight of at least 500 and operable for decreasing the distribution coefficient of the VOCs. Polyoxyalkylene alkanols are preferred polymers. A method of increasing the growth rate of VOC-degrading microorganisms in the bioreactor and a method of increasing the solubility of sparingly soluble VOCs in aqueous solution are also disclosed.

Abstract: The present invention discloses a process for breaking an emulsion comprising water and oil, comprising the steps of mixing an emulsion consisting of water and oil with a culture, bacterial cells or a culture supernatant of a bacterium belonging to the genus Alteromonas or the genus Rhodococcus capable of breaking an emulsion comprising water and oil; and consequently separating said emulsion into an aqueous layer and oil layer; and, a process for breaking an emulsion comprising water and oil, comprising the steps of mixing an emulsion comprising water and oil with bacterial cells of a bacterium belonging to the genus Aeromonas capable of breaking an emulsion comprising water and oil so as to form an aqueous layer and an aggregated layer consisting of bacterial cells and oil, and then separating these layers.

Abstract: A process for biologically enhancing an iron-based redox process for catalytic oxidation of a sulfide compound such as hydrogen sulfide from a gas in a redox system wherein said catalyst comprises a ferric compound and at least one organic chelant capable of holding ferric and ferrous ions in solution at processing temperatures and conditions suitable for generation and retrieval of elemental sulfur, comprising the steps of oxidation of a sulfide compound by a gas with a redox system comprising ferric ions, removal of elemental sulfur from said system, and reoxidation of ferrous ions in the redox system in the presence of a culture of bacteria comprising Thiobacillus ferrooxidans and leptospirillium ferrooxidans at a pH at least as high as about 7.5.

Abstract: A method and apparatus for removing select gas contaminants is disclosed. The apparatus is a bioreactor having a chamber for containing liquid and a liquid positioned therein, the liquid forming a column having a top and a bottom surface defining a height. The bioreactor further has a gas dispersal unit positioned in the column and a selected biomass suspended in the liquid, where the biomass is selected to metabolize the gas contaminant requiring degradation. The method includes feeding a select gas contaminant having a low Henry's coefficient into the gas dispersal unit to produce a stream of bubbles containing the gas contaminants, where the gas contaminant is a food source for said biomass, and allowing the stream of bubbles to sparge through and exit the top of said column.

Abstract: An anaerobic process of desulfurizing a sour natural gas stream wherein a selected consortium of chemoautotrophic bacteria converts H.sub.2 S and other sulfur species into elemental sulfur, which is recovered as a product. The process is conducted at pressures of up to 1000 psi and temperatures up to 140.degree. F. (10.degree. C. to 60.degree. C.), and mitigates up to 10,000 ppm H.sub.2 S to pipeline standards of .ltoreq.4 ppm and up to 10% CO.sub.2 to .ltoreq.2% CO.sub.2.

Abstract: An installation and a method are described for the treatment of a gas containing hydrogen sulphide, the gas (1) being washed in a first gas scrubber (5) with an alkaline wash liquid and the spent wash liquid (4) being treated in an aerobic reactor (6) with oxygen in the presence of sulphide-oxidising bacteria and the effluent (9) from the aerobic reactor (6) being re-used as wash liquid (3) and the elementary sulphur formed during the treatment with oxygen being removed from the effluent (19), the effluent (13) from which sulphur has been removed being treated in an anaerobic reactor (17) with sulphate-reducing bacteria and returned to the aerobic reactor (6). The installation and the method can also be used for simultaneous removal of SO.sub.2, COS, CS.sub.2, NH.sub.3 and HCN.

Abstract: A system for providing improved bulk liquid mixing and effective gas-liquid contacting for mass transfer of the gas to the liquid, especially a non-Newtonian liquid, the viscosity of which decreases when under shearing conditions (shear thinning), in an upright tank. A process, such as fermentation which produces commercial quantities of polysaccharides such as xanthan gum, may be carried out in the tank. An upright draft tube is mounted within the tank and has a lower end spaced from the tank bottom and an upper end spaced below the surface of the liquid in the tank. A plurality of mixing impellers in the draft tube are sufficiently close to each other to establish a field or pattern of agitation to cause shear thinning and upflow throughout the draft tube and which may produce turbulence at the liquid surface. A plurality of radially inwardly projecting, circumferentially spaced baffles extend from the draft tube and are proximate the mixing impellers to prevent swirling of the liquid within the draft tube.

Abstract: The present invention provides a method for treating volatile hazardous air pollutant (VHAP) and volatile organic compound (VOC) waste products from gas streams. The system disclosed herein employs microporous hydrophobic membranes to remove VHAPs/VOCs from a gas stream into an oleophilic stripping fluid. The stripping fluid is directed into a separate biomembrane reactor wherein the VHAPs/VOCs are transferred across a second microporous hydrophobic membrane into an aqueous nutrient medium, where the extracted VHAPs/VOCs are degraded by microorganisms residing on the surface of the membrane. VHAPs/VOCs are degraded to carbon dioxide, water, and cell debris. The disclosed system uncouples biotreatment from waste generation, such that operation of the biotreatment unit can be continuous and optimized independently of plant work schedules or fluctuations in pollutant concentrations entering the system.

Abstract: A soil remedying process for the soil contaminated with a volatile pollutant, which comprises the steps of forming in a probe a remediation site containing a microorganism which can degrade the volatile pollutant, introducing the volatile pollutant into the remediation site in the probe, and degrading the volatile pollutant by the microorganism.

Abstract: A bioremediation apparatus for removal of volatile organic compounds (VOC's) from a contaminated air stream generated from the subsurface remediation of hydrocarbon contaminated ground water and soil is described. The apparatus includes an above ground multilevel biofilter which holds a biologically active media at each level, the levels forming a stack of interlocked levels in series such that the media in each level does not directly contact the media in the adjacent levels. The biofilter includes, a perforated support plate having a multiplicity of holes, the holes having a maximum diameter sufficiently small to prevent significant amounts of the bioactive media from passing there through and a minimum diameter sufficiently large to prevent clogging, the spacing between adjacent holes being selected to produce an overall ratio of total hole area to total plate area of between from about 20% to about 35%.

Abstract: A method for carrying out a well treatment in a well (e.g. fracturing, sand control, etc.) wherein a high-viscosity treatment fluid containing a gel (e.g. a polymeric gelling agent) is flowed down the well along with a bacteria selected from the generic classes of Enterococcus and Corynebacterium or a mixture of the two, which is capable of digesting and/or cleaving the gel to reduce the viscosity of the gel at the conclusion of the well treatment.

Abstract: A method and arrangement for conducting air filtration by biofilter operation is provided. The arrangement generally includes at least one bioreactor bed, through which air to be purified is passed. Preferably the arrangement is configured so that air flow through each tank is from the top downwardly. In general, the biofiltration operation is conducted under pressures of less than ambient, to advantage.

Abstract: Removal of dissolved hydrogen sulfide and a reduction in BOD is achieved by the addition of nitrate ions to waste systems in an amount sufficient to stimulate growth of bacteria which utilize dissolved hydrogen sulfide in their metabolism. Specifically, about 2.4 lbs. nitrate oxygen per lb. of sulfide is required.

Abstract: Removal of dissolved hydrogen sulfide and a reduction in BOD is achieved by the addition of nitrate ions to waste systems in an amount sufficient to stimulate growth of bacteria which utilize dissolved hydrogen sulfide in their metabolism. Specifically, about 2.4 lbs. .Iadd.nitrate .Iaddend.oxygen per lb. of sulfide is required.