Abstract: This disclosure relates to physical selection, deselection or outselection for smaller, less dense, sheared or compressed particles in sludge, wherein the first deselection step occurs at the reactor or at a clarification step, by separately deselecting for such particles and then a second deselection step occurs in an external selector. This double deselection promotes the more efficient removal of slow settling particles, while simultaneously allowing for maintenance of multiple solids residence times for fast and slow growing organisms. The deselection in a clarifier occurs typically at the periphery of the tank or at the surface of a blanket using a positive or negative pressure device. Structures such as slotted or perforated plates, pipes or manifolds can be used to assist in such deselection. Baffles can also be used for such deselection.

Abstract: The present invention describes a method of optimizing CO2 concentration to increase the specific growth rate of Anammox bacteria and methanogens in wastewater and sludge treatment, as well as novel systems and methods of treating wastewater and sludge. The specific growth rate or doubling time of the Anammox bacteria and methanogens were determined to be sensitive to dissolved CO2 concentration. Optimizing dissolved CO2 concentration increases the specific growth rate of the Anammox bacteria, which may be used as an alternative biological nitrogen removal process for the treatment of domestic wastewater. In the method and system of treating sludge, the CO2 stripper returns biogas with low CO2 concentration to the headspace of an anaerobic digester in order to lower the headspace CO2 concentration and therefore, the soluble CO2 concentration. The lower soluble CO2 concentration increases the specific growth rate of the methanogens for a more efficient anaerobic digestion process.

Abstract: Disclosed are a sewage and wastewater treatment system and method using a constant level continuous flow sequencing batch reactor (CSBR). Also, disclosed is a method capable of converting the system into a membrane bio-reactor (MBR) process by means of submerged membranes with a simple configuration. Further, disclosed is an automated foam and scum management and removal system.

Abstract: Disclosed are apparatus and method for alternative aeration-effluent wastewater treatment using a ceramic membrane, which allows the biological treatment to be performed sufficiently in an intermittent aeration tank by combining an anaerobic tank with a plurality of intermittent aeration tanks and selectively changing an inflow path of influent water according to an operation status of the intermittent aeration tanks. The present disclosure is directed to providing an apparatus and method for alternative aeration-effluent wastewater treatment, which allows the aeration and treated water to continuously discharge through two intermittent aeration tanks by independently forming an air injection line and a treated water discharge line at a ceramic membrane provided in each intermittent aeration tank.

Abstract: The present invention provides a method for sludge treatment, comprising the following steps: (1) mixing a sludge feed from a sewage biotreatment process with a first mixed liquor to obtain a second mixed liquor; (2) subjecting the second mixed liquor to an oxygen-supplying process to obtain a third mixed liquor; (3) subjecting the third mixed liquor to an anoxic process to obtain a fourth mixed liquor; (4) separating the fourth mixed liquor to obtain a supernatant liquid and a first concentrated mixed liquor; (5) discharging the supernatant liquid, and returning at least a part of the first concentrated mixed liquor as the first mixed liquor to the step (1), wherein the amount of sludge of the first concentrated mixed liquor that does not return to the step (1) is less than the amount of sludge of the sludge feed. The present invention further relates to the use of the method for sludge treatment in sewage treatment. The method for sludge treatment can achieve a long term stable run without sludge discharge.

Abstract: A method for the biological purification of ammonium-containing wastewater. The wastewater is purified in an aeration tank in which a low oxygen concentration of less than 1.0 mg/l is set so as to first convert, using aerobically oxidizing bacteria, ammonium contained in the wastewater to nitrite and then to convert, using anaerobically oxidizing bacteria, ammonium and nitrite to elemental nitrogen. At least a part of surplus sludge formed in the aeration tank is separated into a heavy sludge phase and a light sludge phase. The light sludge phase is fed as surplus sludge to a sludge digestion. Sludge water that is separated off from the sludge in a sludge dewatering is fed to a deammonifying tank. Nitrogen compounds in the sludge water are converted, by deammonification in the deammonifying tank, to elemental nitrogen. Surplus sludge formed in the deammonifying tank is fed to the aeration tank.

Abstract: A method of treating wastewater containing an organic compound includes feeding wastewater to an anoxic tank, adding compounds containing nitrogen and phosphorus components to wastewater, performing anaerobic treatment on wastewater, and discharging treated wastewater as pre-treated water; introducing pre-treated water into an anaerobic treatment tank, performing anaerobic treatment on pre-treated water, thereby decomposing the organic compound into organic compounds of smaller molecular size and a mixture gas containing methane and carbon dioxide, and discharging treated water as primary water; introducing primary water into an aerobic treatment tank, performing aerobic treatment on primary water, and discharging treated water through a solid-liquid separator as secondary water; and introducing at least a part of secondary water into a reverse osmosis membrane separation unit, and separating part of secondary water into RO permeated water and RO concentrated brine, wherein at least a part of RO concentrated

Abstract: A method and system of treating wastewater is disclosed. The treatment system has a nitrification-denitrification system comprising a sorption system, a biofilm system, and an anaerobic digester that digests or converts at least a portion of the solids or sludge from the sorption system and biofilm system.

Abstract: A method of treating wastewater includes removing BOD and ammonium from the wastewater. The wastewater is directed into a tank where it is mixed with mixed liquor or activated sludge from an activated sludge wastewater treatment system. The mixture of wastewater and mixed liquor or activated sludge forms a mixed liquor stream. The mixed liquor stream is directed to a ballasted flocculation system where suspended solids is removed from the wastewater. This produces a clarified effluent that is directed to a zeolite tank. Clarified wastewater from the ballasted flocculation system is directed into the zeolite tank and mixed with zeolite. Zeolite is effective to remove ammonium from the wastewater. Thus, the process as a whole is effective in removing suspended solids, soluble BOD as a result of mixing the mixed liquor or activated sludge with the wastewater, and ammonium.

Abstract: Waste-treatment processes are enhanced through generation and introduction of specific biological populations customized to perform or favor specific tasks either during the main process, for the formation or precipitation of certain biological nutrients, or to accomplish solids formation reduction in a post-treatment process. These bacteria may be grown from specialized mixes of activated sludge and waste influent by exposing these materials to controlled environments (e.g., in an off-line treatment area). They may then be returned to the main process to perform certain tasks such as converting particulate cBOD into soluble cBOD for utilization, to reduce high solids yield organisms by supplementing the population characteristics with low yield organism characteristics, to provide biological nutrients or oxygenation assistance, to improve nitrification/denitrification efficiency, or to disfavor filamentous biology such as Norcardia sp.

Abstract: Systems and methods for treating wastewater including a dissolved air flotation operation performed upon a portion of a mixed liquor output from a contact tank prior to the mixed liquor entering a biological treatment tank.

Abstract: Method for treating wastewater, in particular municipal wastewater, in which the wastewater is initially received in an equalization basin reactor for performing an infiltration and inflow equalization process. The equalization basin reactor has sufficient capacity for the increased inflow of wastewater received under wet weather conditions. However, the increased inflow is not merely stored in the equalization basin reactor for later processing, but the wastewater treatment process continues throughout the wet weather period with the first stage wastewater treatment being performed in the equalization basin reactor, which further provides a substantially constant outflow of partially treated wastewater for subsequent treatment stages.

Abstract: A hybrid method and system of treating wastewater with reduced energy usage is disclosed. The treatment system has a sorption system, an anaerobic digester that digests or converts at least a portion of the solids or sludge from the sorption system, and an aerobic treatment tank that partially reduces oxygen demand of a portion of the sludge from the sorption tank.

Abstract: The present invention relates to a process for treating wastewater that includes the steps of: —a contact step, wherein wastewater contacts bacteria retained on a support surface and the dissolved oxygen concentration of the wastewater is maintained at 2.0 mg/l or less; an aeration step, wherein gas is passed through wastewater that has passed through the contact step and the dissolved oxygen concentration of the wastewater is reduced as the wastewater passes through the aeration step; a sedimentation step, wherein wastewater that has passed through the aeration step is substantially separated into treated water and sludge; and a sludge recycling step, wherein sludge from the sedimentation step is passed to the contact step. The invention also relates to a processing unit on which the aforementioned process may be operated.

Abstract: Methods and systems are provided for treating wastewater to simultaneously remove nitrogen, carbon, and phosphorus. The process includes an anoxic tank that receives at least two streams, including plant influent wastewater and return activated sludge. These streams are mixed in the anoxic tank to promote phosphorus release and fermentation of particulate and dissolved organic matter. The mixed liquor is transferred to an aerated tank having low dissolved oxygen concentrations to promote development of phosphorus-release bacteria that is eventually recycled to the anoxic tank by way of the return activated sludge. Simultaneous nitrification, denitrification, and phosphorus release occur in the aerated tank. A membrane tank separates treated effluent from activated sludge in a membrane tank.

Abstract: Methods and systems for utilizing biological wastewater treatment processes to remove nutrients from wastewater containing reduced sulfide compounds may include treating the wastewater in an anaerobic zone, an anoxic zone, and an aerobic zone. The wastewater is first treated in the anaerobic zone to uptake residual biodegradable organic material using specialized bacteria known as phosphorus accumulating organisms (“PAOs”) and glycogen accumulating organisms (“GAOs”). After treatment in the anaerobic zone, the wastewater is treated in an anoxic zone to convert nitrates to nitrogen gas and sulfur to sulfates. Following treatment in the anoxic zone, the wastewater is treated in the aerobic zone to oxidize ammonia to nitrate and to complete removal of phosphorus. After treatment in the aerobic zone, the wastewater may be treated in other zones, or may be delivered to a liquid-solids treatment stage.

Abstract: A biological nutrient removal (BNR) system to treat a typical U.S. municipal/domestic wastewater. This BNR system consists of four main directly interflowing of anaerobic, aerobic, anoxic and re-aeration. In the municipal/domestic wastewater treatment industry, the past multi-stage suspended waste activated sludge treatment facilities have been adding coagulant chemicals such as alum to remove total phosphorous (TP) and total nitrogen (TN) to 1.0 mg/l and 3.0 mg/l, respectively. This BNR system is a unique activated sludge biological configuration capable of treating wastewater biologically for clarifier effluent TP and clarifier effluent TN to a level less than 1.0 mg/l for each pollutant without any coagulant chemical additions.

Abstract: The present invention relates to systems and processes of wastewater treatment and, in particular, to systems and methods of treating wastewater utilizing biological treatments utilizing two mixed liquor recycle streams for nutrient removal.

Abstract: Methods and systems are provided for treating wastewater to simultaneously remove nitrogen, carbon, and phosphorus, while recovering energy in the form of methane and carbon dioxide. An ammonia-containing stream is directed to a pretreatment tank that produces excess sludge, biogas, and a pretreated stream. The pretreated stream has at least 45% less carbon than the ammonia-containing stream. The pretreated stream is then directed to an anoxic tank, which promotes phosphorus release and fermentation of particulate and dissolved organic matter. The mixed liquor is transferred to an aerated tank having low dissolved oxygen concentrations to promote development of phosphorus-release bacteria that is eventually recycled to the anoxic tank by way of the return activated sludge. Simultaneous nitrification, denitrification, and phosphorus release occur in the aerated tank. A membrane tank separates treated effluent from activated sludge in a membrane tank.

Abstract: An apparatus and method for selecting, retaining or bioaugmenting solids in an activated sludge process for improving wastewater treatment using screens. The screens can be used to separate and retain solids based on size, compressibility or shear resistance. The screens are used to separate and select slow growing organisms, faster settling organisms, or materials added to absorb, treat or remove constituents in the activated sludge process. A swapping screen arrangement provides another means of selecting various particles. The exposed shear rate or time, particle compression, or SRTs can be adjusted manually and/or automatically in response to detected readings from an instrument such as a spectrophotometer or other optical approaches to optimize selection of organisms.

Abstract: Treatment systems are described which uncouple the solids retention time (SRT) of the recycling bacteria from the wasting bacteria. Elevated recycling bacteria SRTs increase concentrations of nitrifying bacteria in the aeration basin and Anammox bacteria in the anoxic basin, improving nitrification and anaerobic ammonium oxidation. Fluorescence in situ hybridizations were used to identify and determine the abundance of nitrifying bacteria and Anammox bacteria (recycling bacteria) in freshly settled sludge of biological nutrient removal (BNR) secondary clarifiers. An uneven distribution was observed for recycling bacteria in two BNR systems. Settling patterns suggest microcolony formation processes are sensitive to the internal recycle rate, which allow for rapid recycling bacteria microcolony growth by increasing circulation of flocs through the aeration and anoxic basins. Uncoupling the SRT enhances aeration and/or anoxic basin utilization and reduces the overall hydraulic residence time.

Abstract: A hybrid method and system of treating wastewater with reduced energy usage is disclosed. The treatment system has a sorption system, an anaerobic digester that digests or converts at least a portion of the solids or sludge from the sorption system, and an aerobic treatment tank that partially reduces oxygen demand of a portion of the sludge from the sorption tank.

Abstract: Fluorescence in situ hybridizations were used to identify and determine the abundance of nitrifying bacteria and Anammox bacteria (recycling bacteria) in freshly settled sludge of biological nutrient removal (BNR) secondary clarifiers. An uneven distribution was observed for recycling bacteria in two BNR systems. Settling patterns suggest microcolony formation processes are sensitive to the internal recycle rate, which allow for rapid recycling bacteria microcolony growth by increasing circulation of flocs through the aeration and anoxic basins. Sludge containing high levels of recycling bacteria are selectively collected and separated from the remaining sludge, uncoupling the solids retention time (SRT) of the recycling bacteria from the wasting bacteria. Elevated recycling bacteria SRTs increase concentrations of nitrifying bacteria in the aeration basin and Anammox bacteria in the anoxic basin, improving nitrification and anaerobic ammonium oxidation.

Abstract: A method for creating Class A compost for sale to the public from waste products, especially municipal sewage, involving lower expense and improved versatility over prior methods.

Abstract: Waste-treatment processes are enhanced through generation and introduction of specific biological populations customized to perform or favor specific tasks either during the main process, for the formation or precipitation of certain biological nutrients, or to accomplish solids formation reduction in a post-treatment process. These bacteria may be grown from specialized mixes of activated sludge and waste influent by exposing these materials to controlled environments (e.g., in an off-line treatment area). They may then be returned to the main process to perform certain tasks such as converting particulate cBOD into soluble cBOD for utilization, to reduce high solids yield organisms by supplementing the population characteristics with low yield organism characteristics, to provide biological nutrients or oxygenation assistance, to improve nitrification/denitrification efficiency, or to disfavor filamentous biology such as Norcardia sp.

Abstract: A process for converting organic waste materials into usable products and products thereof is disclosed. According to the process, organic waste materials are contacted with an oxidant to form a product and then an amount of the oxidant is removed from the product to form a reactor-ready feedstock. The oxidant is removed by various means, including washing, photolysis, catalytic means, oxidation of the oxidant, reduction of the oxidant, and heat. The reactor-ready feedstock may then be introduced into a reactor, such as a digester or incubator, and the reactor-ready feedstock is converted by microorganisms into biofuel or other products.

Abstract: The present disclosure relates to methods of treating highly contaminated wastewater using waste activated sludge as an adsorbent.

Abstract: Disclosed is a system for reducing the demand of wastewater volume flowing through a wastewater collection piping system thereby increasing the effective capacity of the system. A portion of the wastewater is diverted from a sewer main. The solids are separated from the liquid; for example, by a centrifugal separator such as a vortex or cyclone separator. The recovered liquid can be treated and made available for reuse or disposed of. The separated or concentrated solids are reintroduced into the sewer main dynamically in a portion that adjusts the wastewater loading, or alternatively, the solids loading, in the sewer main to a predetermined amount or predetermined range. The system can be adapted to reducing demand of wastewater volume flowing within a wastewater treatment plant by diverting the wastewater in the flow path between the wastewater plant inlet and the biological processing stage and reintroducing separated solids downstream.

Abstract: The invention relates to a method for biologically treating waste water, using a set of micro-organisms having different metabolic spectra, in order to eliminate carbon and nitrogen, even phosphorus. Some of the micro-organisms are fixed to mobile solid carriers (2) and form a fluidised fixed biomass. Some of the micro-organisms are free to be used in an activated mud treatment. To this end, a first non-aerated treatment zone (21a) is followed by a second aerated treatment zone (21b); the treated effluent is subjected to a solid/liquid separation by flotation (6) at a speed higher than 10 m/H; and part of the mud recovered by flotation is recirculated (8) towards the activated mud treatment, said recirculation being controlled (9, 10, 11) so that the MES concentration of the effluent subjected to the liquid/solid separation remains compatible with the retained flotation.

Abstract: The present invention relates to a sewage/wastewater treatment system comprising a rectangular upflow anaerobic/oxygen-free reaction tank and a method of treating sewage/wastewater using the same. The rectangular upflow anaerobic/oxygen-free reaction tank comprises a water introducing unit, an inlet unit being in fluid communication with the water introducing unit and having a plurality of through-holes formed therein through which water introduced from the water introducing unit can pass, a mixing unit comprising a main shaft and a plurality of spaced-apart stirring blades fixed to the main shaft, and an outlet unit for collecting water after being treated in the anaerobic/oxygen-free reaction tank. The system and method can treat sewage/wastewater cost-effectively.

Abstract: Biologically treated wastewater is directed as mixed liquor from a treatment tank to a downstream filtration tank having a having a submerged membrane module extending across the cross-sectional area of the filtration tank. Mixed liquor is directed from the bottom of the filtration tank upwardly into the membrane module such that substantially all of the mixed liquor received in the bottom of the filtration tank flows through the membrane module. A permeate stream is produced. A portion of a non-permeate stream is recirculated to the treatment tank. The filtration tank is sized such that there is no substantial recycle of mixed liquor in the filtration tank. Once the mixed liquor in the filtration tank makes one pass through the membrane module the mixed liquor is recycled to the treatment tank and generally not permitted to be recycled through the membrane module without first returning to the treatment tank.

Abstract: A system for treating ammonia-based wastewater is provided. The system includes a first reactor, including: denitrification bacteria for denitrification; a second reactor disposed on the back of the first reactor, wherein the second reactor includes an aerator and aerobic heterotrophic bacteria, and has an HRT of less than 6 hours; a third reactor disposed on the back of the first reactor, wherein the third reactor contains nitrification bacteria carried on the carriers for improving nitrification; and a solid-liquid-separating reactor disposed on the back of the third for separating the solids and liquids in the effluent of the third reactor.

Abstract: An integrated bioreactor and its applications as well as a method for treatment of highly-concentrated organic wastewater using the same. The integrated bioreactor with a concentric columnar structure includes an inner layer and an outer layer, in which the inner layer is an upflow anaerobic sludge blanket (UASB) and the outer layer is a moving bed biofilm reactor (MBBR). The effluent of the MBBR is recycled into UASB via a reflux pump mounted between a water tank and the integrated bioreactor. A water outlet of the UASB is arranged with an on-line pH monitor and a mechanical agitation device is arranged on the top of a bottom water distributor. The bioreactor is low in cost, features friendly maintenance, stable operation, and high degree of automation, and can be applied under low temperature.

Abstract: In the field of water treatment, this invention relates to economical methods, processes and apparatus for preparing Class A bio-solids wherein: dewatering costs and energy costs are efficient, the solids product has reduced ammonia and sulfide odor, and the concentration of solids in the aqueous solids may vary from approximately 3 to approximately 90 percent. This invention presents mesMophilic and thermophilic digestion in concert, wherein mesophilic digestion incorporates strains of Thiobacillus with nitrifiers to remove sulfide(s) and ammonia from bio-solids. Chemical dewatering of thermophilic digested bio-solids is accomplished incorporating a cationic, quatemized or an anionic polyacrylamide with at least one selected from a list consisting of: an aluminum salt, an iron salt, an amine comprising a quatemized nitrogen moiety and any combination therein. A quatemized polyacrylamide is presented alone.

Abstract: An advanced water treatment method processes a continuous flow of water in a sequence of stages including pre-filtering to remove solids, conditioning to adjust pH, blending with a recycled dense microalgae culture, and passing the resulting mixture through an enclosed, environmentally-controlled photobioreactor where nutrients, PCB's, trace metals and other pollutants and regulated compounds are taken up by the algae. The flow from the PBR is separated using cross-flow filtration to produce a treated water flow and a dense microalgae flow that is recycled to the blending stage upstream. Thus, whereas the algae is recycled, the water entering the system is treated by flowing sequentially through the stages of the system, without any recycling or repetition of treatment stages.

Abstract: A method for treating waste-activated sludge comprises adding (1) a pozzolanic material to waste-activated sludge to form a mixture. The mixture is homogenized and aerated (2). The pozzolanic material reacts with the waste-activated sludge. The mixture is allowed to settle (3). A portion of the mixture is recirculated (4) from a downstream location to an upstream location. The recycled mixture includes pozzolanic material. Some embodiments provide advantages over existing wastewater treatment methods which may include: reduction or elimination of unpleasant odours, reduction of overall costs, conversion of waste into useful products, and/or reduction or elimination of discharged bacteria or other undesirable materials.

Abstract: Treatment system for wastewater containing ammonium is provided. The treatment system of the present invention includes an ammonia oxidation reactor and a membrane reactor disposed on the back of the ammonia oxidation reactor. The ammonia oxidation reactor includes biological carriers for carrying the ammonium oxidation bacteria and nitrite oxidation bacteria, a pH level controller for increasing the pH level to above 7.5, and a DO (dissolved oxygen) controller for reducing the DO content to less than 1.0 mg/L. The membrane reactor composed of a membrane and an aerator is used to separate the solids and liquids of the effluent of the ammonia oxidation reactor. In addition, a method for treating wastewater containing ammonium is also provided.

Abstract: Methods and systems are provided for reducing ammonia partially by a denitrification process. A stream containing ammonia is contacted with oxygen to form a first product stream in low dissolved oxygen conditions. The ratio of oxygen to nitrogen is about 2.28 g O2/g N—NH3 (2.28 grams of oxygen per gram of nitrogen in ammonia) or less. The first product stream is then exposed to organic matter in an amount of 0.57 g COD/g N—NH3 (0.57 grams of chemical oxygen demand per gram of nitrogen in ammonia). This microbial reaction ultimately produces nitrogen gas, water, and carbon dioxide.

Abstract: Disclosed herein is an advanced wastewater treatment device. The device includes a wastewater treatment bath having an anaerobic bath in which phosphorus is discharged, an anoxic bath in which denitrification of nitrate nitrogen is performed, and an aerobic bath in which decomposition and nitrification of organic matter is performed. A first movable divider separates the anaerobic bath from the anoxic bath and is movably provided in the wastewater treatment bath to change relative volume of the anaerobic and anoxic baths. A second movable divider separates the anoxic bath from the aerobic bath and is movably provided in the wastewater treatment bath to change relative volume of the anoxic and aerobic baths. A divider moving unit moves the first and second movable dividers. An air supply unit includes air nozzles, an air pump, and valves. A recycling unit recycles activated sludge of the aerobic bath to the anoxic bath.

Abstract: Wastewaters are treated by an activated sludge process that includes combining wastewater with bacteria-laden sludge in an activated sludge tank to form a mixed liquor, separating the mixed liquor into a clear effluent and activated sludge stream, pretreating at least a portion of the activated sludge stream in a conditioning tank, transferring at least a portion of the activated sludge stream in the conditioning tank to an interchange bioreactor operating in batch or continuous flow mode, processing the activated sludge stream within the interchange bioreactor by selecting desired growth conditions to cultivate at least one type of bacteria in the activated sludge stream, and returning at least a portion of the activated sludge stream in the bioreactor to the activated sludge tank. The process may further include a sidestream reactor to remove phosphates from the activated sludge stream leaving the interchange bioreactor.

Abstract: A hybrid method and system of treating wastewater with reduced energy usage is disclosed. The treatment system has a sorption system, an anaerobic digester that digests or converts at least a portion of the solids or sludge from the sorption system, and an aerobic treatment tank that partially reduces oxygen demand of a portion of the sludge from the sorption tank.

Abstract: A method for removing contaminant from feedwater by forming a dispersion comprising bubbles of a treatment gas in a continuous phase comprising feedwater, wherein the bubbles have a mean diameter of less than about 5 ?m and wherein the treatment gas is selected from the group consisting of air, oxygen, and chlorine. A method for removing contaminants from a feedwater by subjecting a fluid mixture comprising feedwater and a treatment gas to a shear rate greater than 20,000 s?1 in a high shear device to produce a dispersion of treatment gas in a continuous phase of the feedwater. A system for treating feedwater to remove contaminants therefrom is also presented, the system comprising at least one high shear mixing device comprising at least one generator comprising a rotor and a stator separated by a shear gap; and a pump configured for delivering feedwater and treatment gas to the high shear mixing device.

Abstract: The invention provides a side stream type membrane bioreactor process which does not cause an excessive fall in the MLSS concentration in a bioreactor, does not require any additional effluent treatment facility for discharging backwash effluent, and can further ensure the stability of the membrane filtration performance of a separation membrane. According to the invention, in a side stream type membrane bioreactor process, a backwash effluent containing foulants that are generated by backwashing a separation membrane is collected in a backwash effluent tank, and subjected to ozone treatment, and the resultant is returned to a bioreactor. By this ozone treatment, the foulants close to the membrane pore size of the separation membrane are made fine or are made into a state be easily taken into activated sludge flocs. Therefore, even when the treated effluent is returned to the bioreactor, the membrane filtration performance of the separation membrane is not deteriorated.

Abstract: A process for treating waste water to remove phosphorous and nitrogen in a treatment system including an anaerobic zone (5) containing an anaerobic mixed liquor having organisms which release phosphorous into the anaerobic mixed liquor; an anoxic zone (7) containing an anoxic mixed liquor having organisms which uptake phosphorous and denitrify the anoxic mixed liquor and an aerobic zone (9) containing an aerobic mixed liquor having organisms which uptake phosphorous and nitrify the aerobic mixed liquor; the process including the steps of providing wastewater to be treated into the anaerobic zone (5) and communicating anaerobic mixed liquor from the anaerobic zone (5) to the anoxic zone (7). The anoxic mixed liquor is then communicated from the anoxic zone (7) to the anaerobic zone (5) and the anoxic mixed liquor from the anoxic zone (7) to the amble zone (9).

Abstract: It is described a method for manufacture of sanitised organic sludge, said method comprising the following steps: mechanical mixing of a cellulose containing component, a super absorbent and dewatered organic sludge; leading the mixture to a sanitising container; continuously supplying air to the sludge mixture until the desired temperature has been reached. The super absorbent increases the moisture retention of the sludge mixture, such that odor and leakage is prevented during composting. The cellulose component, preferably shredded newspaper, admits increased air supply to the sludge mixture. The method may be used to treat sewage sludge, hydrocarbon polluted soil and waste from fish processing or abattoirs.

Abstract: A method and system for treating organically contaminated waste water for reuse, by: introducing the waste water into a sedimentation tank to remove a significant portion of the organic contaminants; circulating the waste water from the sedimentation tank to an anoxic mixing chamber for denitrifying the waste water; circulating the waste water from the anoxic mixing chamber to a rotary biological contactor to nitrify the waste water by aeration, and to assimilate organic materials therein by bringing the waste water into contact with a biological medium, to thereby output nitrified waste water; and recirculating a portion of the nitrified waste water outputted from the rotary biological contactor back to the anoxic mixing chamber to enhance the nitrifying and denitrifying of the waste water.

Abstract: A wastewater treatment system has two separate but interlinked tanks containing four different zones, namely aerobic, microaerophilic, anoxic and anaerobic, for the biological treatment of the wastewater, as well as two clarification zones and a filtration unit for separation of solids from liquid. The first tank contains the aerobic, microaerophilic and anoxic zone as well as a clarification zone, while the second dank includes the anaerobic zone, a solid-liquid separation zone and a filtration unit. The aerobic zone is an airlift reactor that contains air diffusers at the bottom of the zone to introduce air into the zone. The air bubbles mix the liquid and its content of microorganisms, and provide oxygen for the aerobic biological processes that take place in this zone. Aeration also produces circulation of liquid between the aerobic zone and its adjacent microaerophilic and anoxic zones that are located at the sides and under the aerobic zone, respectively.

Abstract: Waste treatment systems and methods of using them to treat septage, domestic sludge or both are disclosed. Certain examples provided herein relate to waste treatment systems that include a plurality of stages, such as, for example, a plurality of ecosystems, configured to treat domestic sludge, septage or both.

Abstract: A method of wastewater treatment that reduced equipment cost and running cost and realizes high efficiency implementation and further tank miniaturization, and that reduces excess sludge withdrawal. There is provided a method of wastewater treatment with excess sludge withdrawal reduced, characterized in that there are installed an aeration tank wherein wastewater is brought into contact with carrier particles under aerobic conditions, a total oxidization tank and a sedimentation tank, and that operation is made while maintaining the BOD sludge load in the total oxidization tank at 0.08 kg-BOD/Kg-MLSS*day or smaller, and that a coagulant is charged in the complete oxidization tank in order to improve the setting in the sedimentation tank.

Abstract: Waste-treatment processes are enhanced through generation and introduction of specific biological populations customized to perform or favor specific tasks either during the main process, or for solids minimization purposes in a post-treatment process. These bacteria may be grown from specialized mixes of activated sludge and waste influent by exposing these materials to controlled environments (e.g., in an off-line treatment area). They may then be added back to the main process to perform certain tasks such as converting particulate cBOD into soluble cBOD for utilization, to reduce high solids yield organisms by supplementing the population with low yield organisms, to improve nitrification/denitrification efficiency, or to disfavor filamentous biology such as Norcardia sp.