Abstract: The invention relates to a process for the biological treatment of waste water, in which a mixture of activated sludge and waste water is treated with gas in an activation stage and the activated sludge is separated off from the treated waste water by flotation, wherein the concentration of the activated sludge in the activation stage is .gtoreq.6 g/l and wherein the flotation is a pressure-relief flotation.

Abstract: An activated sludge treatment apparatus having an aeration tank 14 for subjecting an organic waste water to an aerobic biological treatment, a first precipitation device 16 for separating a waste water treated in aeration tank 14 into treated water and a sludge, a recycle route 18 for returning a portion of the sludge separated by precipitation device 16 to aeration tank 14, a solubilizing treatment device 24 for solubilizing, at a high temperature, excess sludge separated by precipitation device 16, and a return route 30 for returning a treated solution solubilized by solubilizing treatment device 24 to aeration tank 14, is disclosed.

Abstract: In a sealed container, organic material, more especially biowaste is composted. The exhaust air from the sealed container is purified in an exhaust air cleaning unit. In order to improve the cleaning effect, the condensate water from the exhaust air cleaning unit is supplied to a high performance bioreactor, in which it is brought into contact with atmospheric oxygen and is agitated. The suspension leaving from the bioreactor is caused to flow in a circuit through an ultra-filtration module for purifying the water.

Abstract: A wastewater treatment method involving mixing of the wastewater with an activated sludge and water that has been supersaturated with air under high pressure is described. After the pressure is reduced two processes are carried out which are biological oxidation of pollutants by activated sludge and flotation of suspended solids. A portion of the treated water is saturated with air and returned to the beginning of the process. The waste activated sludge is removed along with some floated and biologically non-oxidated pollutant particles.

Abstract: A method for treating wastewater is useful in treatment of biomass (sludge) resulting from wastewater treatment, particularly for biological sludges of aerobic, facultative and/or anaerobic origin. The invention relates fractionation of microorganisms and organic materials within the sludge by mechanical shearing, in combination with heat, chemical and/or biochemical treatment to improve waste treatment and to release nutrients for recirculation for use by microorganisms in the waste treatment system.

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 process for treating waste water uses the combination of a septic tank operating in series with a biological reactor such as a sequencing batch reactor. In this process, waste water is supplied and accumulated in a septic tank. In the septic tank, the waste water and the settling sludge are biologically treated under anaerobic conditions. A given amount of treated waste water is then transferred from the septic tank into a biological reactor such as a sequencing batch reactor, where it is mixed and aerated. Such a mixing and aerating causes activation of the sludge and clarification of the waste water. The activated sludge in suspension in the liquor is then allowed to settle and an upper layer of clarified water formed above the mixed liquor after the settling period is decanted. The excess activated sludge in the biological reactor may then be removed therefrom and supplied into the septic tank so that the excess sludge be treated by digestion therein.

Abstract: A wastewater treating apparatus has first, second and third bioreactors. Each bioreactor has, in an upper position, a reaction/sprinkling portion for exhaust gas treatment. The first bioreactor has, in a lower position, a submerged portion including an aerobic upper portion and an anaerobic lower portion. The aerobic upper portion includes a membrane filter. A membrane concentrated liquid produced by the membrane filter is introduced into a mixing tank. A mixture of an alcohol, fine powdered material and membrane concentrated liquid from the mixing tank is introduced, together with a developer-containing wastewater, into the anaerobic lower portion, so that a granular sludge is formed therein. The granular sludge contains anaerobic microorganisms in a high concentration level and is therefore capable of treating the wastewater without necessity of wastewater dilution or use of chemicals.

Abstract: A wastewater treatment apparatus is provided which includes at least an aeration chamber and a clarification chamber having a common wall therebetween, a transfer port opening through the common wall between a lower portion of the clarification chamber and the aeration chamber, an aerator mechanism in the aeration chamber for creating wastewater flow currents which flow through an inlet portion of a flow augmenting device located in the common wall above the transfer port. The flow augmenting device is a conduit or pipe having a discharge outlet adjacent the lower portion of the clarification chamber through which exits the flow from the aeration chamber resulting in solid particles being agitated and returned from the clarification chamber lower portion into the aeration chamber through the transfer port.

Abstract: Process for the treatment of liquid effluents, such as waste water, for the purpose of removal of carbon, nitrogen and phosphorus pollution using an activated sludge, according to which the effluent, after having been subjected to mechanical pretreatments, is brought into contact with the activated sludge. The effluent/activated sludge mixture is the subjected to clarification/settling in order to separate the treated water from the thickened sludge, the latter then being recycled at the head of the aeration treatment and the excess sludge being continuously discharged. An inert material of inorganic origin is injected into the activated sludge, this material being immediately and homogeneously dispersed in the activated sludge, in order to create a mixed culture containing both, and in a single bacterial floc, free heterotrophic species and autotrophic species partially fixed on the particles of the said material within the floc.

Abstract: A wastewater treatment system mixes return activated sludge with influent wastewater under anoxic conditions in the presence of luxury uptake organisms to cause release of phosphorous compounds into the surrounding wastewater. The wastewater is then aerated in the presence of nitrifying organisms to convert ammonia into nitrate while the luxury uptake organisms take up the phosphorous compounds. The wastewater is next subjected to alternating anoxic and oxic conditions to reduce the nitrate to nitrogen gas using denitrifying organisms. The resulting effluent is substantially free of nitrogen-based phosphorous-based nutrients.

Abstract: An apparatus and method are provided that are useful in a process for treating organic wastewater for the removal of phosphorus and nitrogen compounds. The apparatus includes an anoxic zone, an oxic zone, and an anaerobic treatment zone, each having therein microorganisms that are operable to affect biological denitrification, BOD oxidation, luxury-uptake of phosphorus and formation of nitrates.

Abstract: A pressurized process for the treatment of high-solids wastewater having relatively high BOD and phosphorus concentration includes anaerobic and aerobic treatment. The treated wastewater effluent is discharged in an environmentally safe manner such that the residue BOD and P are concentrated in the solid fraction which may be a source of protein.

Abstract: A system for purifying nitrogenous waste water by biological nitrification and denitrification, comprises at least two essentially separated reactor chambers, a liquid supply (4) and a liquid discharge (5). The first, aerated reactor chamber (1) is provided at the top with an overflow to the second, oxygen-depleted reactor chamber (2). The oxygen-depleted reactor chamber (2) is divided at the top into a degassing chamber (7) and a settling chamber (8) having an overflow (9) to the liquid discharge. The first reactor chamber is provided with an air supply (11, 18) and an air discharge (12) located above the supply. The first reactor chamber may be partly divided into a riser (14) and a downcomer (15) which allow, as a result of the air supply, mass circulation to take place in the aerated reactor chamber.

Abstract: A system for wastewater and sludge treatment utilizes an anaerobic reactor to modify the wastewater and generate sludge and liquid effluent. The sludge is transferred to a conditioner wherein anaerobic, aerobic and chemical means may be utilized to cultivate the required strains of organisms and break down various pollutants. Various chemicals may be solubilized, or precipitated, or adsorbed to remove them from the waste stream. Aerobic conditioning may be used to increase the volume of sludge, and to increase the temperature of the sludge. A shell having multiple compartments can provide for the entire process by utilizing the upper portion for anaerobic reaction and the lower portion for conditioning. An aerobic reactor can be disposed centrally of the conditioning compartments. Pipes and pumps can be used to transfer components from one compartment to another, and to discharge the cleaned effluent. The sludge is further subjected to aerobic reaction and bioheating.

Abstract: A sequencing batch reactor is controlled to provide an effective, efficient treatment of raw waste water. Controls include regular withdrawal of mixed liquor during each cycle of operation. The withdrawal is volumetrically controlled to provide a sludge retention time of 5 to 10 days in the system. This produces a carbon and nitrogen oxydizing bacterial culture with good setting properties. Hydraulic loads in the system are controlled according to liquid levels, while the bacterial processes are controlled by timed sequences. A storm control procedure monitors the influent rate and shortens the cycle times according to the magnitude rate, to increase the system capacity. The system also includes a novel effluent withdrawal system, with a check valve controlled intake about midway up the reactor. This is trouble-free, with the check valve preventing sludge entry into the effluent withdrawal and maintaining prime on the effluent withdrawal pump.

Abstract: A process for the treatment of organic waste is described which comprises the steps of:a) feeding input waste in an input line to an ATAD reactor where the waste is subjected to biological digestion;b) settling out a portion of a biomass formed in the digestion unit;c) hydrolyzing the separated portion in a hydrolysis vessel;d) returning hydrolyzed effluent to the input line upstream of the ATAD reactor; ande) periodically removing clear decant from the reactor. Variations of this process include removal of nutrients from the clear decant; feeding solid organic 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.

Abstract: The invention provides processes for treating waste water comprising subjecting waste water to liquid phase oxidation without catalyst, liquid phase oxidation with catalyst and anaerobic digestion and/or aerobic treatment.

Abstract: An activated sludge sewage treatment process wherein sewage is received into a sewage treating basin in first zone into which activated sludge is mixed and retained for a period sufficient to form a non-bulking sludge and absorb biodegradable dissolved compounds into the activated sludge, and aerated and subjected to a quiescent condition to permit settling of the sludge in a zone characterized in that it has less than approximately twenty percent of the biochemical oxygen demand of the original sewage and where in the sludge is non-bulking, decanting treated sewage from the upper portion of the basin after allowing the sludge to settle, and cyclically repeating the process, anaerobically fermenting the influent sewage, and recycling anaerobically fermented partially treated sewage to the input of the influent sewage is disclosed.

Abstract: A method and system for removing pollutants dissolved in the aqueous discharge of a plant, such as a power plant, from a body of water having known hydraulogy and physicochemical characteristics, the method comprising (a) modifying the hydraulic system of the body of water including use of physical barriers to define a zone in a portion of the body of water which zone includes the discharge point and where the water has a range of physicochemical characteristics; (b) selecting a large and preferably filamentous, planktonically growing strain of algae adapted to absorb the particular pollutants and genetically dominating algae at the physicochemical characteristics of the zone; (c) establishing a colony of the selected algal strain in the zone; (d) harvesting a portion of the colony; and (e) reinnoculating the zone near the discharge point with a fraction of the harvested portion. The fraction used for reinnoculation can be adjusted to balance the rate of pollutant removal to the rate of pollutant discharge.

Abstract: A waste water treatment plant of simple design and high efficiency which is particularly adapted for use in small communities is described. The plant comprises a reaction tank and an aeration tank, inlet means to admit raw waste water continuously into the reaction tank, a first airlift pump or a penstock to transfer waste water intermittently from the reaction tank to the aeration tank to displace treated waste water therefrom through an outlet, aerators to aerate the aeration tank when the first airlift pump or penstock is inoperative, a second pump for transferring sludge and waste water from the aeration tank to the reaction tank after the first airlift pump has ceased operation and before the aerator is actuated, and control means to stop the aeration in sufficient time before actuation of the first airlift pump or penstock to allow substantial settling of the sludge in the aeration tank.

Abstract: In the method for concentrating/dehydrating sewage sludge including activated sludge with the aid of organic polyelectrolytes and/or inorganic flocculators the activated sludge portion is produced in an aerated biologic clearing step in presence of--based on the amount of liquid flowing into the clearing step--5 to 0.01 parts by weight per million parts by weight of at least one compound selected from the group consisting of folic acid, dihydrofolic acid and at least an ammonium alkali metal salt, alkaline earth metal salt and alkanolammonium salt thereof.

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: Process for the psychrophilic biological purification of waste waters having medium-low concentrations of polluting substances. The process comprises a first anaerobic treatment step with an expanded mud bed of U.A.S.B. type at a low flow rate, a second treatment step comprising a fluid-bed treatment on a fine support at a high flow rate, and a final treatment step comprising anaerobic treatment for the nitrification and oxydation of the various substances reduced in the previous treatments. The flow is then recycled to the upstream steps for the removal of possible nutrients, such as nitrogen and phosphorus.

Abstract: A waste treatment and water recycling system that includes a delivery system, a trap, a sump, an anoxic reactor, an aerobic digestion chamber, a filtering system, an adsorption system, a disinfecting system and a water return system. The delivery system includes one or more flush-type toilets and urinals which receive flush water from the water return system and deliver the toilet and urinal waste and flush water to the anoxic reactor. The anoxic reactor contains bacteria which utilizes organics in the toilet waste to convert oxidized nitrogen compounds, such as nitrates, to nitrogen gas, produce bicarbonates and other products. The bacteria, in accomplishing this, lower the organic load on subsequent processes.

Abstract: In a process for the biological sewage purification of sewage containing organic as well as nitrogen-containing pollutants, carbon decomposition and nitrogen removal are performed. The sewage is gassed with air and/or pure oxygen in a reactor in the presence of a biomass fixed on a support material and then, in a secondary sedimentation step, is separated into purified water and sludge. The sludge is at least partially recycled into the reactor. Particles of support material in lumpy and/or granulated form and in free-flowing quantities are employed in the reactor as support material for the microorganisms. To attain both a high carbon and a high nitrogen decomposition at the same time, the reaction is provided with BOD.sub.5 volume load of 0.4 to 2.5 kg/m.sup.3 d and a TKN volume load of 0.1 to 0.8 kg/m.sup.3. d, BOD.sub.5 decomposition, nitrification and denitrification are all performed within an undivided reactor, in which the O.sub.2 concentration within the liquid is 0.

Abstract: A process is described for producing an animal feed, comparable to feathermeal in properties and appearance, from two waste products: float sludge and activated sludge. The process uses a bulking agent for extracting excess fat from the sludges, particularly the float sludge, while a mixture of the sludges and the bulking agent is being stirred, heated, and dried. Blood, chicken litter, meat scrap, and the like can be substituted for activated sludge to provide protein. The bulking agent can be any material that can expose the sludges to air, that is capable of absorbing fat, and that can be separated from the dried and partially de-fatted sludges. Wood chips are the preferred bulking agent. Wood shavings, shredded cardboard, shredded newspaper, paunch manure, and the like can be substituted for wood chips as the bulking agent.

Abstract: The present invention provides for an improved method of operating an activated sludge system whereby a significant amount of ammoniacal nitrogen is removed in the BOD sorption zone, which does not later appear in the system as protein or NOX. The improved method for achieving said ammoniacal nitrogen removal comprises decreasing the ammoniacal nitrogen concentration of the mixed liquor in the oxidation zone to a point where the mixed liquor leaving the oxidation zone has an ammoniacal nitrogen concentration less than about 0.3 ppm. Additionally, an overall F/M.sub.o ratio equal to or greater than about 0.05 is maintained.

Abstract: According to an embodiment thereof, the method comprises using a pair of reaction vessels, sequentially, to treat the sludge. Both vessels are pressurized, and the first thereof has an aerator for aerating the sludge, and receives sulfuric acid and chlorine thereinto through a port. A dewatering device is provided upstream of the first vessel, and the outlet of the first vessel is coupled to an inlet of the second vessel through another dewatering device. The second vessel defines a final-treatment chamber in which the sludge is exposed to ozone, air and lime. The treatment method, then, comprises the steps namely: introducing the sludge into the first vessel and oxidizing and depressing the pH of the sludge so introduced, and recycling the sludge in the first vessel over a given period of time. Thereafter the sludge is dewatered and conducted to the second vessel wherein it is exposed to air, ozone and lime, as aforesaid, and discharged after a like period of time.

Abstract: The present invention provides a method and apparatus for economical and efficient composting. The apparatus includes a manifold with lances coupled thereto for even fluid distribution throughout the compost. The manifold is designed to direct fluid flow to a portion of the lances while simultaneously removing fluid flow from the other portion of lances. This creates substantially uniform patterns of fluid injection and evacuation for uniform composting, reduced energy requirements and greater control of process conditions. Further, reversal of the fluid flow enhances control of process conditions and adds an automatic self cleaning aspect to the apparatus.

Abstract: A method and apparatus for treating sewage and converting the sewage into organic fertilizer which utilizes equipment for converting the solid material of the sewage into patties and a mixing apparatus for mixing the patties with bulking agents. The mixture of patties and bulking agents is stored in a pile and subjected to a supply of air to enhance the self-combustion or oxidation of the organic material in the patties. The bulking agents provide the patty-bulking agent mixture with air passages and pockets and minimize compaction of the patties. The self-combustion of the patties continues until the organic material is burned out, leaving a residual ash. A shaker separator having an elongated longitudinal perforated member is reciprocated to separate the ash from the bulking agents. The ash is collected and utilized as organic fertilizer. The bulking agents are recycled back to the mixing apparatus.

Abstract: An improved process is disclosed for the treatment of aqueous waste streams containing nitrogenous matter (nitrate or nitrite ions or matter capable of forming nitrate and nitrite ions) in the presence of sufficient carbonaceous matter to permit substantially complete denitrification of the aqueous effluent. The process comprises introducing an aqueous waste stream having a pH less than 6 into an anaerobic treatment zone containing anaerobic activated sludge at a rate such that the concentrations of nitrate and nitrite ions in the anaerobic treatment zone are maintained at a level less than 3 milligrams/liter. In embodiments, the effluent from the anaerobic treatment zone is passed to an aerobic treatment zone effluent from which is recycled at a rate at least equal to that at which untreated waste is fed to the anaerobic treatment zone. The waste stream feed may contain phenol.

Abstract: There is disclosed a method for the preparation of an animal feed supplement from fish cannery waste process water in which the water is maintained under aerobic conditions and is processed through a flotation cell to separate the oils and proteins contained in the water as a concentrated sludge. The sludge is dewatered, blended with a bulk, solid carrier preserved against oxidative spoilage of the lipids with an effective anti-oxidant, and dried in vacuum under low temperature conditions to obtain an animal feed supplement in dry particulate form. The processing of the waste water is done under aerobic conditions to promote the growth of yeast and non-toxic, aerobic, bacterial improve color and odor and texture, and enhance the feed value of the sludge recovered from the processing.

Abstract: A modified activated sludge system is provided wherein BOD-containing wastewater and recycled sludge are initially admixed under anaerobic conditions in the substantial absence of oxygen or oxidizing agents and subsequently subjected to aeration and clarification. By the disclosed operation the selective production of non-bulking biomass is favored while effective removal of phosphates is obtained. By a further alternative modification, nitrates and nitrites are also removed by interposing an anoxic treating zone between the anaerobic zone and the aerating zone.