Abstract: A modular system for treating wastewater is designed having different phases. In an initial phase, plural tanks are provided, including at least one reactor and digester tank. In a subsequent phase, at least one of the tanks is converted into a different type of tank, and additional new tanks are provided to accommodate larger quantities of wastewater. In one embodiment, conversion of at least one of the tanks is accomplished by removing a temporary wall from a digester tank to create another reactor tank.

Abstract: A method and an apparatus for treating an organic waste water capable of deodorizing an exhaust gas diffused into an atmosphere is provided, wherein heat energy loss is small and the amount of an organic or inorganic nitrogen compounds in an effluent from the apparatus is low. In the method of the present invention, an organic waste water is nitrified in a nitrification device 8, denitrified in a denitrification device 9, and subjected to an aerobic biological treatment in an aeration tank 10, and then the treated mixture is solid-liquid separated in a solid-liquid separation device 3. A portion of an excess sludge separated in solid-liquid separation device 3 is solubilized at a high temperature in a solubilization device 6, and the solution after a solubilization treatment is returned to denitrification device 9 and a gas exhausted from solubilization device 6 is charged into nitrification device 8.

Abstract: A wastewater treatment process having improved solids separation characteristics and reduced biochemical oxygen demand (BOD) in the purified wastewater comprising the steps of: passing wastewater through a main aerobic biological oxidation zone and therein oxidizing a portion of the BOD a portion of the ammonia nitrogen content (NH.sub.

Abstract: A method of treating an organic waste water, which is capable of separating and recovering phosphorus components in a liquid or solid form, is provided. According to the method of the present invention, reuse of phosphorus components can be facilitated, while the content of phosphorus components contained in a large quantity of a primary treated liquid can be reduced.

Abstract: The invention provides a system 10 for treatment and purification of domestic household effluent, and for the elimination within said system of organic solid wastes, comprising elements 12 and 14 for separately collecting first and second constituents of the sewage of a domestic residential unit, lavatory sewage comprising said first sewage constituent, and bath, shower, wash basin, laundry, kitchen sink sewage and the like comprising said second sewage constituent, a first and a second dual-purpose vessel 22 and 24, each vessel having at least one inlet port 18 and 20 and at least one outlet port 26, 28, 30, 32 and being arranged so that during the time period that one of said vessels 22 receives said first sewage constituent and acts as a collector and settling tank, the remaining vessel 24 operates as an anaerobic reaction vessel, the vessel operating as an anaerobic reaction vessel carrying out a decomposition process during which the volume of sludge 34 contained therein is greatly reduced by conversion

Abstract: A method and apparatus for treating waste material to remove selected components form the waste is described using a reactor or a series of reactors in fluid communication with each other for receiving the waste to be treated as influent. The influent forms a biomass including the waste and microorganisms and is treated by controlling the metabolic activity of the microorganisms by monitoring the oxygen utilisation rate or the potential oxygen utilisation rate of the biomass so as to determine the required amount of oxygen to be supplied to the biomass and to determine the period of aeration of the biomass in order to maintain a predetermined oxygen utilisation rate or value so as to remove the selected components of the waste. The preferred selected components to be removed are nitrogenous, carbonaceous and/or biological phosphorus containing materials or derivatives.

Abstract: A wastewater treatment process having improved solids separation characteristics and reduced biochemical oxygen demand (BOD) in the purified wastewater comprising the steps of: passing wastewater containing suspended solids and biodegradable organic substances through a main aerobic biological oxidation zone; passing the effluent from said aerobic biological oxidation zone to an aerobic/mixing zone and therein mixing said effluent with effluent from the anoxic/anaerobic zone; passing the effluent from said aerobic/mixing zone to a settling zone and therein separating purified wastewater and sludge containing suspended solids; passing a portion of the sludge formed in the settling zone and volatile acids to an anoxic/anaerobic zone; and recycling an effective amount of the effluent from said anoxic/anaerobic zone to said aerobic/mixing zone.

Abstract: A method of biological treatment of materials by a combination of at least two groups of microorganisms forming sludges in at least two biological treatment zones treating the said materials wherein for purposes of increasing the treatment efficiency and stability at least one said sludges is conditioned in at least one sludge conditioning zone, whereby converting at least a fraction of at least one said group of organisms into organisms of another group, and thus forming the conditioned sludge, and the said conditioned sludge is fed in at least one said biological treatment zone.

Abstract: Recycling apparatus for use in a closed-loop waste-treatment system includes components for removal of inert materials. Typically, the system includes a treatment vessel used in conjunction with a clarifier in an internal recycle configuration; clear water from the top of the clarifier is conducted away from the system as treated effluent, while a portion of the biomass settling at the bottom of the clarifier is returned to the head of the treatment vessel through a hydrocyclone and screen arrangement to remove inert content, thereby substantially increasing the efficiency of biological waste-digestion processes.

Abstract: The present invention entails a method and system for enhancing biological nitrification in a wastewater treatment process. The process entails both a mainstream wastewater process and a sidestream process wherein the sidestream process produces an abundant supply of supplemental nitrifiers that are in turn directed into the mainstream for assisting in carrying out the nitrification process in the mainstream. Specifically, the sidestream process includes directing a liquid stream (such as a dewatering liquid) having a high ammonia concentration at an elevated temperature into a sidestream nitrification zone which is operated at conditions which maximize production of nitrifiers therein. Afterwards, the resulting nitrifiers produced in the sidestream nitrification zone are directed into the mainstream where the nitrifiers function to enhance nitrification in the mainstream and allows operation at low sludge retention time conditions where nitrification otherwise could not be sustained.

Abstract: An aquaculture process for dissolving gas in liquid by impinging two or more streams substantially and directly one to the other wherein the two streams enter an impingement zone from conveying means of substantially equal shape with a velocity greater than 2 ft/sec, wherein at least one of the streams is a gas/liquid mixture and at least one of the streams passes through a venturi prior to impingement, the impingement of the two streams taking place above a water line of an environment being discharged into so as to offset the pressure of the fluid discharging from the process, the impingement of the two streams further taking place in a contained environment such that the fluid dynamics of each stream just prior to and after the point of impingement is substantially turbulent, whereby after impingement, the streams are discharged at velocities that have substantially turbulent fluid dynamics with the discharge from the impingement zone not changing direction before discharge to the surrounding environment,

Abstract: The invention relates to a nutrient rich humus material produced by a process wherein solids in an aqueous slurry of animal excrement are settled or precipitated in a solids ecoreactor, the slurry may be treated before and/or after settlement in the ecoreactor by passing to a bioreactor wherein soluble phosphorus may be precipitated with metallic salts, the slurry is aerobically and anaerobically treated to form an active biomass that actively bioconverts remaining soluble phosphorus, nitrogen and organics, and the aqueous slurry containing bioconverted phosphorus is recycled to said solids ecoreactor and/or discharged, and at least a portion of slurry is bioconverted and recovered as a beneficial humus material.

Abstract: A method for removing contaminants from a surface such as pavement using a portable closed-loop system which is transported to the location to be cleaned by a vehicle. The method includes storing a volume of fluid in a clean tank, pumping the fluid to a cleaning head, blasting the surface to be cleaned with the fluid, suctioning the contaminants from the surface, removing suspended and colloidal contaminants, removing hydrocarbons, and returning this fluid to the clean fluid tank for recirculation through the system.

Abstract: A method for qualifying a chemical distribution system and components used therein to ensure that the quantity of contaminants extracted from the system by the chemical is below a predetermined specification level. A volume of the chemical is continuously circulated through the system. The concentrations of extracted contaminants in the chemical are periodically measured, and the contaminant extraction rate determined as a function of the measurements. The system is qualified for production when the extraction rate has decreased to the specification level.

Abstract: The invention relates to a improved process for the biological transformation of phosphorus and nitrogen containing storm water runoff into ecologically manageable materials by a process wherein aqueous storm water runoff is passed to a bioreactor where soluble phosphorus is precipitated with metallic salts, the aqueous fluid is aerobically and anaerobically treated to form an active biomass that actively bioconverts remaining soluble phosphorus and nitrogen, and the aqueous fluid containing bioconverted phosphorus and nitrogen is passed to an ecoreactor wherein at least a portion of the biomass is bioconverted to a beneficial humus material.

Abstract: A process and apparatus for biological purification of wastewater resulting in reduction of biological oxygen demand, reduction of suspended solids, and for nitrification, wherein the process involves aerating wastewater in a treatment zone for reduction of biological oxygen demand, transferring the mixed liquor from this treatment zone on an alternate basis to a second or third treatment zone which undergoes an aeration/settle, fill and decant cycle. As the second or third zone is receiving influent, it is being decanted in a modified plug-flow fashion. The alternate treatment zones allow for a continuous discharge of treated effluent during the process. During aeration of the second or third treatment zone, mixed liquor is recycled to the first treatment zone. Sludge is retained long enough to achieve nitrification. This invention is particularly suited for modification of aerated lagoon systems to achieve nitrification with a high degree of efficiency.

Abstract: A starting mixture of liquid and solid organic wastes that is susceptible to at least partial microbiological degradation, with formation of biogas, is treated by the following process. The mixture is mechanically separated into a first sludge phase with enriched dry substance and a first liquid phase containing dilute solids. The first liquid phase is subjected to anaerobic treatment leading to formation of biogas and to the development of a second sludge phase and a second liquid phase. The first sludge phase is subjected to aerobic treatment resulting in the formation of compost, fertilizer, or feed. At least part of the second sludge phase is recirculated into the starting mixture, thereby causing the formation of biogas in the starting mixture and facilitating decomposition of higher compounds contained in the starting mixture.

Abstract: The present invention provides apparatus and method for increasing the wastewater treatment capacity of an existing pond treatment facility wherein the facility includes at least one treatment pond and means for bringing influent wastewater to the pond. Apparatus according to the present invention includes a porous baffle placed into the pond so as to separate the pond into two separate and distinct, but fluidly connected portions. The baffle thus divides the pond into a first portion for treatment of biological solids in the wastewater with the use of concentrated bacteriological growth and a second portion which provides a reservoir to accommodate high rates of wastewater flows and organic loads such as will occur with storm water flow.

Abstract: The invention relates to a nutrient rich humus material produced by a process wherein solids in an aqueous slurry of the excrement are precipitated in a solids ecoreactor, the treated slurry is passed to a bioreactor wherein soluble phosphorus is precipitated with metallic salts, the slurry is aerobically and anaerobically treated to form an active biomass that actively bioconverts remaining soluble phosphorus and the aqueous slurry containing bioconverted phosphorus is recycled to said solids ecoreactor wherein the at least a portion of slurry is bioconverted and recovered as a beneficial humus material.

Abstract: The present invention entails a nitrification-denitrification wastewater treatment process where nitrification and denitrification is carried out in three separate treatment basins. First, wastewater influent is directed from a supply line into a first basin where the wastewater is subject to denitrification. Wastewater held in a second basin is subjected to nitrification while the influent wastewater is directed into the first basin. Effluent from the first basin that is being filled is directed directly to a third basin which performs both denitrification and nitrification at various times during the total process. Purified wastewater from the third basin is directed to a clarifier which separates activated sludge from the purified wastewater and the activated sludge is returned and mixed with the influent wastewater. After a selected time period the influent wastewater being directed to the first treatment basin is switched to where the wastewater influent is now directed into the second treatment basin.

Abstract: Processes for the treatment of organic waste are disclosed, including feeding the organic waste to an ATAD reactor and subjecting the organic waste to biological digestion in the ATAD reactor in order to produce a biomass and clear decant therein, oxidizing at least a portion of the biomass so as to produce an oxidized effluent therein, and returning the oxidized effluent to the ATAD reactor. Variations on these processes which are disclosed include the removal of nutrients from the clear decant, treating of the organic waste with a mixer prior to feeding it to the ATAD reactor, feeding the waste by a grinder upstream of the mixer, feeding the mixed material initially to an AAD vessel from which methane gas is removed, and then to the ATAD reactor, with or without nutrient removal, the use of solid separation for the effluent from the ATAD reactor, and other such variants.

Abstract: The present invention relates to a process for treating wastewater utilizing a step feed return activated sludge process. The wastewater is directed via one or more step feed points through a mainstream process. The step feed point includes at least one aerobic zone and at least one anoxic zone, in repeating or alternating sequence. A portion of effluent from the one or more anoxic zones are fed through at least one anaerobic zone to which raw or pretreated wastewater is fed and returned to the upstream portion of the anoxic zone. Additionally, return activated sludge may be recycled to one or more of the anoxic zones.

Abstract: The invention relates to a improved process for the biological transformation of phosphorus and nitrogen containing animal waste excrement into ecologically manageable materials by a process wherein solids in an aqueous slurry of the excrement are precipitated in a solids ecoreactor, the treated slurry is passed to a bioreactor zone where it is soluble phosphorus is precipitated with metallic salts, the slurry is aerobically and anaerobically treated to form an active biomass that actively bioconverts remaining soluble phosphorus and the aqueous slurry containing bioconverted phosphorus is passed to a polishing ecoreactor zone wherein the at least a portion of slurry is bioconverted to a beneficial humus material.

Abstract: A sequencing batch waste treatment facility with pretreatment mixing and equalization by mixing with selectively bred bacteria to achieve a selected waste to bacteria ratio, wherein waste is treated and reduced to acceptable biological oxygen demand levels for municipal-type waste treatment or general discharge per regulatory permit. A treatment colony of mature bacteria is cultivated and maintained in a treatment tank while a colony of young bacteria, separate from the treatment colony, is selectively bred in a bacteria tank to be particularly adapted to digest the waste being treated. Newly received waste is mixed to break macroscopic solid waste apart, into microscopic solid waste and to blend solid waste and liquid waste components into a waste slurry. Some of the selectively bred bacteria are portioned and mixed into the waste slurry up to an equalization point. The equalized batch of waste slurry is subsequently transferred to treatment.

Abstract: Methods are described for pretreating microbial sludges to break cells and disrupt organic matter. One method involves the use of sonication, and another method involves the use of shear forces. The pretreatment of sludge enhances bioconversion of the organic fraction. This allows for efficient dewatering of the sludge and reduces the cost for final disposal of the waste.

Abstract: Wastewater is treated by promoting the presence and growth of BPR organisms, which have the ability to absorb and retain an amount of phosphorus in excess of the amount required by the BPR organisms for metabolism and cell growth. In the process, a mixture of influent wastewater (10) and activated sludge (14) containing BPR organisms is first subjected to a period of incubation in an anoxic zone (20) followed by a period of incubation in an anaerobic zone (30). Volatile fatty acids (VFA's) (16) are added in the anaerobic zone (30). The mixture is then subjected to an aerobic zone (41). The wastewater mixture (46) leaving the aerobic zone is clarified in a clarifier (50), causing activated sludge to settle. The activated sludge contains BPR organisms which are engorged with phosphorus absorbed from the wastewater. The clarified wastewater (52) becomes effluent from the system. The activated sludge (54) is removed from the clarifier (50).

Abstract: A process and apparatus is disclosed for treating waste water. After treatment, essentially no sludge remains for disposal. The treatment includes mixing the waste water with activated sludge solids in an aeration tank (15). The mixed liquor from the tank is then moved to a clarifier settling tank (17). About 5-25% of the activated sludge separated in the settling tank is returned to an aerobic digester (23) and treated for about 16-24 hours. The aerobic digester can be a batch unit or a continuous process unit. After treatment in the aerobic digester, the activated sludge solids are returned to the aeration tank (15).

Abstract: Conventional biological processes for treating wastewater include the so-called activated sludge process which is continuous and the sequencing batch reaction (SBR) activated sludge process. The first process requires the use of dedicated, relatively expensive external clarifiers, and the second process is inefficient in terms of treatment volume. A modified sequencing batch reactor process and system enable the efficient, continuous treatment and discharge of wastewater, combing the advantages of the SBR and activated sludge processes. In the present case, wastewater is initially fed in a first direction through a plurality of contiguous cells, the wastewater is subjected at all times to biological treatment in a plurality of such cells and settled in at least one of the cells immediately prior to discharge from the system.

Abstract: A modified activated sludge system is provided wherein wastewater is treated to reduce BOD, nitrogen, and/or phosphorus. The disclosed system features a zone sequence nitrification/denitrification, with nitrification induced by recycling mixed liquor that contains a significant concentration of oxygen and nitrifying bacteria. With a further modification, the main treatment zones of the treatment system are split into two or more parallel treatment trains that are either high-loaded with BOD or low-loaded with BOD. The high-loaded sections facilitate the sludge generation and BOD removal, while the low-loaded sections are operated for nitrification and to enhance the growth of nitrifying bacteria. The parallel treatment zones combine and pass into a final denitrification zone. Phosphorus removal is achieved with phosphate release in a reverse flow regime to the main treatment, and phosphate retention primarily in aerated treatment zones in the main stream of the process.

Abstract: A method in which a miscellaneous drain water purifying device having a plurality of separator tanks connected to miscellaneous drain water sources via a change valve, receiving miscellaneous drain water, leaving it stagnant, and separating sedimentation and floating substances and a decomposition tank connected to a plurality of the respective separator tanks and receiving flow-out liquid from the sedimentation separator tanks is used, while one of the sedimentation separator tanks receives miscellaneous drain water and carries out sedimentation separation of sludge, sends out the top level clear water in the quantity equal to the received water quantity to the decomposition tank and carries out purifying treatment, an aeration treatment of the sludge separated from miscellaneous drain water by the previous stage prior to transfer is carried out in the other separator tank which is shut off from the miscellaneous drain water sources via the change valve; such transfer is alternatively repeated at suitable in

Abstract: A wastewater treatment system incorporates three interconnected, but separately controlled, processes to enhance biological phosphorus removal. The first process is a mainstream biological treatment process utilizing aerobic and solids separation zones and the provision of return activated sludge. The next is a first sidestream process for anoxic/anaerobic "selection" of desirable BPR organisms. Finally, a second sidestream process serves to ferment organic material in some of the return activated sludge to produce food utilized in the first sidestream selection process. The system permits the three processes to be separated from each other by creating two sidestreams, allowing all three processes to be controlled separately and optimized in satisfying their own specific goals.

Abstract: Raw sewage ("black water" from toilets), wastewater from showers, sinks, kitchen facilities ("grey water") and oily water from the bilge of a host vessel ("oily water"), in combination, unexpectedly provide the essential nutrients for a live mass of mixed microorganisms which are peculiarly well-adapted to ingest the nutrients. To facilitate availability of oxygen to the microorganisms so as to provide growth of the microorganisms, and also, to allow them destroy to themselves, excess oxygen is discharged, in a combination of microbubbles and macrobubbles, into a membrane bioreactor ("MBR"). The mixture of bubbles is preferably generated with coarse (>2 mm) and fine (<20 .mu.m) bubble diffusers. An auxiliary stream, whether alone, or a recirculating stream into which air is drawn, may provide the coarse bubbles. The air is entrained, in a jet aerator or eductor, in a recirculating loop of activated sludge taken from the MBR.

Abstract: A wastewater orbital treatment system includes an elongated racetrack-like tank containing a central partition wall. A surface aerator is mounted adjacent to at least one end of the partition wall to both aerate and propel the mixed liquor including biomass around the orbital tank. An aerobic zone for BOD and ammonia oxidation is provided in an upper layer of the moving volume of mixed liquor and an anoxic zone for reduction of NO.sub.x from the aerobic zone, by anoxic respiration by the biomass, is provided in a lower layer of the moving volume of mixed liquor. An imperforate horizontal baffle is provided under the surface aerator so as to prevent dissolved oxygen in the aerobic zone from entering the anoxic zone. The NO.sub.x from the aerobic zone is introduced through a free interface of the two vertically displaced zones downstream of the baffle.

Abstract: A biochemically enhanced hybrid anaerobic reactor (BEHAR) system has been developed for treatment of high strength industrial wastewaters. The process is designed and operated based on specific criteria developed around critical biochemical and microbiological principles of the facultative and anaerobic microorganisms involved in anaerobic treatment. Biological kinetic relationships developed by the inventor for substrate removal, methane gas production, and biogas quality control as a function of the mass substrate loading rate are used for designing and operating the BEHAR process. A specific formulation of biological growth micronutrients has been developed for enhancing the anaerobic treatment process. Ferric chloride, one of the chemicals used as a micronutrient, is also utilized for sulfide toxicity control, biogas cleaning without scrubbing, and odor control.

Abstract: Conventional biological processes for treating wastewater include the so-called activated sludge process which is continuous and the sequencing batch reactor (SBR) activated sludge process. The first process requires the use of dedicated, relatively expensive external clarifiers, and the second process is inefficient in terms of treatment volume. A modified sequencing batch reactor process and system enable the efficient, continuous treatment of wastewater, combining the advantages of the SBR and activated sludge processes. Wastewater is treated in three contiguous treatment sections, each of which includes a plurality of contiguous cells. In a first series of operations, the flow direction is from the first to the third sections, and in a second series of operations the flow is reversed. In each series of operations, the first step is to aerobically treat the wastewater, and then allow the sludge to settle before discharging the treated wastewater from the system.

Abstract: Bioremediation or other liquid waste biotreatment operations are enhanced by the use of turbulence promoters to create turbulent flow conditions in an oxygen/liquid waste dispersion prior to passage in an improved gas/liquid distribution system for passage through eductors into a lagoon or other holding source of the liquid waste being treated.

Abstract: An aqueous medium in which glucoamylase is dissolved, is contacted with nitrogen-functionalized amorphous precipitated silica having a pore diameter at the maximum of the volume pore size distribution function of from about 7 to about 100 nanometers, whereby at least a portion of the glucoamylase is adsorbed by the nitrogen-functionalized amorphous precipitated silica. The process is particularly suitable for removing glucoamylase from draught beer.

Abstract: The present invention relates to a process at the purification of water, in particular sewage water, comprising a nitrification process and a denitrification process during simultaneous decomposition of a pre-precipitated sludge of sewage water. The invention is characterized in that decomposed sludge or solutions of sludge of a chemical pre-precipitation of sewage water is added as a source of carbon at the denitrification step.

Abstract: In a system for biodegrading oxidizable organic waste in a bioreactor in combination with a membrane ultrafiltration unit used to separate a high quality permeate from activated sludge which is returned to the bioreactor from the membrane unit as a recycle stream, it has been found that an in-line fine bubble diffuser or "micronizer" takes advantage of the kinetic energy in the recycle stream to aerate the biomass with surprising efficiency. The micronizer is positioned external to the biomass in the bioreactor; the discharge from the micronizer provides a microaerated tail-jet of the recycle stream which has been infused with a mass of air bubbles from 1-1000 .mu.m in diameter. The velocity of the compressed air flowed into the micronizer keeps its pores from clogging with sludge. The energy of the recycle stream without the air is insufficient to provide the requisite motive force for adequate oxygen transfer and to establish a predetermined recirculation pattern.

Abstract: A process and a plant for the purification of waste water wherein the waste water is alternatingly treated in the two treatment zones under anoxic and aerobic conditions and the waste water thus treated is subjected to an aerobic treatment in a separate zone before it is introduced into a clarification zone from which purified waste water and sludge is removed, at least a part of the sludge being recycled to the waste water which is introduced into one of the two treatment zones.

Abstract: The invention relates to an apparatus and process useful for the biological transformation of waste materials into ecologically desirable materials. A meta system reactor is disclosed comprising three primary zones which are cyclically and dynamically connected by a circulating fluid. In the process of the invention, each of a bioreactor zone, solids ecoreactor zone and georeactor zone further comprise secondary subsystems and are cyclically connected by a series of recycle flows and organism movements to bioconvert the contained materials. The converted materials produced can be desirable and ecologically beneficial end products comprising gases such as nitrogen, oxygen, carbon dioxide, and water vapor; a biologically active and highly beneficial humus material; and clean water which may be passed through a final wetlands polishing and biomonitoring system before discharge into a natural receiving water.

Abstract: The invention relates to a method for processing manure, comprising the steps of:i) adding an organic carrier liquid to the manure;ii) concentrating the mixture of manure and carrier liquid;iii) condensing the formed vapor;vi) anaerobic treating of the condensate; andv) aerobic treating of the effluent from the anaerobic treatment.Preferably the effluent deriving from the anaerobic treatment is denitrified in a denitrification unit and nitrified in a nitrification unit, and wherein a portion of the sludge-influent mixture from the nitrification unit is recirculated to the denitrification unit.The treating yield is greater than 90%, preferably greater than 95%, such as 97-99% BOD.

Abstract: An improved powdered adsorbent enhanced sludge process for the treatment of wastewater is disclosed that allows for in situ recovery of unregenerated powdered adsorbent. In situ recovery is performed by contacting a mixture of activated sludge and spent powdered adsorbent at disassociation conditions whereby cell lysis occurs. The cell lysis allows for physical separation of the spent powdered adsorbent from the activated sludge, thus allowing for recycle of adsorbent without the need for a regeneration process.

Abstract: The treatment of water by a biological technique. The water to be treated circulates in the interior of the reactor, in the space (2) located above the partition (1). It is aerated and agitated by a diffuser (3); it enters the reactor by the opening (4) and leaves by the opening (5). A volume of confined water, poor in oxygen, occupies at the bottom of the reactor the space (6) located below the partition (1) and has across its thickness a layer supersaturated in oxygen (10) occupied by the microalgae and aerobic microorganisms; a region rich in oxygen (11) occupied by aerobic microorganisms; a region (12) poor in oxygen and occupied by anaerobic microorganisms; and an intermediate region (13) occupied by aerobic and anaerobic microorganisms. The invention is applicable particularly, in its closed circuit configuration, to aquaria and by means of either a closed circuit or an open circuit, to the treatment of water.

Abstract: The present invention relates to a reactor for biological purification of pollutant-containing water in a closed vessel by means of loop operation. This vessel contains, disposed vertically and concentrically with respect to its jacket and to each other, an insertable pipe that is open at both ends, into which a nozzle projects for the purpose of supplying the water-gas-biomass mixture to be purified, and a guide pipe that is open at both ends and that forms an inner annulus with the internal insertable pipe and an outer annulus with the reactor jacket. This guide pipe projects above and below the ends of the insertable pipe. A deflector plate is mounted below the insertable pipe but inside the guide pipe, so that part of the biomass-water mixture is deflected back into the inner annulus. A conically shaped sedimentation chamber is disposed in the lower part of the reactor.

Abstract: This invention relates to an improved process for the treatment of municipal waste and particularly to the reduction of organic sludges generated in the biological digestion of organic material. In the conventional processes the waste containing organic matter is contacted with an oxygen-containing gas in the presence of biologically active organisms under conditions to produce biomass which, on separation, forms a sludge. A portion of the sludge often is returned to the aerobic digestion process. This invention relates to an improvement for sludge reduction in these processes wherein a portion of the sludge is hydrolyzed and then subjected to biological digestion in an autothermal aerobic digestion zone. The effluent from the autothermal aerobic digestion zone usually is returned to the initial aerobic digestion process or submitted for disposal.

Abstract: Water contaminated with at least one volatile compound is treated by air stripping the volatile compound into the gas phase, then removing the volatile compound from the gas phase by contacting it with an aqueous mixture of biological solids and powdered adsorbent. The partially-purified water is further treated by a biophysical aerobic process which in turn produces the aqueous mixture of biological solids and powdered adsorbent used to remove the volatile compound from the gas phase. The aqueous mixture of biological solids and powdered adsorbent containing the volatile compound is thickened and the solids slurry treated by regeneration, preferrably wet air oxidation, to destroy the biological solids and volatile compound as well as regenerate the powdered adsorbent. The regenrated adsorbent may be returned to the biophysical aerobic treatment process.

Abstract: A method and apparatus for an anaerobic process to reduce caustic requirements and to facilitate dissolution of organic acid having limited solubility by combining effluent from an anaerobic reactor having dissolved carbon dioxide with fresh feed containing the organic acid and stripping the carbon dioxide from the mixture to raise the pH.

Abstract: A process is disclosed for decreasing the phosphorus content of an aqueous influent stream containing biodegradable substrates, comprising adding to said stream previous aerobically enhanced and anaerobically stressed bacteria; dividing said stream into separate first and second streams; treating the first stream in an aerobic zone, in the presence of sufficient oxygen, for a time sufficient to cause enhancement of the bacteria to take-up phosphorus in excess of their growth requirements; treating the second stream in an anaerobic zone containing less than about 1 ppm of oxygen, for a time sufficient to stress the bacteria and cause release of phosphorus which is nonessential for the bacteria growth requirements; intimately mixing said treated first and second stream; holding said mixed first and second streams to allow settling of precipitants; removing liquid effluent from the upper portion of the settled stream; removing high solids content sludge, containing bacteria and phosphorus from the lower portion

Abstract: In a sludge thickener, supernatant fluid is drawn off via peripheral ducts and oxygenated at a suitable location. The supernatant fluid is thereafter reintroduced into the thickener via diffusers distributed transversely of the thickener and intermediate the peripheral ducts. The generation of nauseating smells is thereby prevented, and an advantageous increase of the concentration of the sludges is attained.