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: Disclosed are a wastewater treatment plant and a wastewater treatment method. The wastewater treatment plant includes: a reactor including a gas outlet, a treated water outlet, and an inlet through which wastewater and gas are supplied, through which the wastewater is introduced, to perform aeration and denitrification; a sludge separation means including plural reaction unit bodies stacked inside the reactor to divide the interior of the reactor into upper and lower sides and separating sludge in a aeration process by forming a gas hold-up space for collecting the gas rising from a lower portion of the reactor; and a aeration unit introducing gas into the reactor.

Abstract: A wastewater treatment system includes wastewater having nitrogen-containing compounds, an anoxic zone having denitrifying bacteria, and an aerobic zone having nitrifying bacteria. The anoxic zone is coupled to the aerobic zone, and wastewater flows from the anoxic to the aerobic zone or vice versa. A fluidized bed heat exchanger configured to accept heat from a heat engine and to transfer the heat from the heat engine to the wastewater is positioned in the aerobic zone or the anoxic zone. The fluidized bed heat exchanger includes particulate media, and fluidization of the particulate media scrubs bacterial growth from portions of the fluidized bed heat exchanger. Treating wastewater can include flowing wastewater having nitrogen-containing compounds into a biological reactor having an anoxic zone and an aerobic zone, and heating the wastewater with heat from a heat engine to facilitate denitrification reactions in the anoxic zone and nitrification reactions in the aerobic zone.

Abstract: An aquarium filter element having a removable insert. The removable insert may include a chemical agent or biological agent for treating aquarium water.

Abstract: A nitrification carrier having made nitrifying bacteria dominant therein and a denitrification carrier having made anaerobic ammonium-oxidizing bacteria dominant therein are mixed in a treatment tank. Both of a nitrification reaction with the nitrification carrier and a denitrification reaction with denitrification carrier are allowed to proceed in the treatment tank to decompose ammonium nitrogen in wastewater to nitrogen gas. The ratio of the bacterial loads of the nitrifying bacteria and the anaerobic ammonium-oxidizing bacteria can be easily controlled by immobilizing the nitrifying bacteria and the anaerobic ammonium-oxidizing bacteria on different carriers from each other (nitrification carrier and denitrification carrier) and by controlling the volume ratio (ratio of the feeding amounts) of the nitrification carrier and the denitrification carrier.

Abstract: A method for the treatment of effluents containing nitrogen in the form of ammonium, in which: a volume of effluent is introduced into the batch reactor in successive volume fractions, each volume fraction being treated during a subcycle, each subcycle including a phase of feeding with a volume fraction and, in an alternating manner, two treatment stages, i.e. an aerated first stage, during which complete or partial oxidation of the ammonium takes place to give nitrites, followed by a nonaerated second stage, during which the nitrites produced and the ammonium are converted to nitrogen gas. During the aerated first stage, the dissolved oxygen concentration in the batch reactor is maintained between 0.1 mgO2/l and 0.6 mgO2/l; the N—NO2:N—NH4 ratio is adjusted to be between 0.9 and 1.5 at the beginning of the nonaerated stage; and the nonaerated phase is carried out by deammonification, without the provision of carbon-based substrate.

Abstract: A wastewater treatment method for treating wastewater containing ammonium nitrogen, includes the steps of: charging an unacclimated denitrification carrier containing anaerobic ammonium-oxidizing bacteria into a treatment tank; charging an unacclimated nitrification carrier containing nitrifying bacteria into the treatment tank; acclimating the unacclimated denitrification carrier in the treatment tank under an anaerobic condition; acclimating the unacclimated nitrification carrier in the treatment tank under an aerobic condition, after having acclimated the denitrification carrier; nitriting the ammonium nitrogen in the wastewater to generate nitrite with the acclimated nitrification carrier; and denitrifying the nitrite generated by nitriting the ammonium nitrogen with the acclimated denitrification carrier, while using the ammonium nitrogen in the wastewater as a hydrogen donor.

Abstract: The present invention is directed to a novel process and method for treating nitrogen that is contained in an organic waste stream using aeration at a preferred predetermined mass loading in an aerobic volume followed by treatment in an anoxic/anaerobic volume. The present invention also includes the solid humus material produced from the treatment of an organic waste stream aeration at a predetermined loading in an aerobic volume followed by treatment in an anoxic/anaerobic volume and the removal of said humus solids.

Abstract: An exemplary method of treating nitrogen-contaminated wastewaters, especially those with high ammonia concentrations, according to the invention includes the steps of ammonia degassing and recapture, and of nutrient assimilation with microalgae. Organic nitrogen, organic carbon, phosphorus, heavy metals and other compounds may also be removed in different embodiments of the invention. Examples of applicable wastewaters include landfill leachate, municipal solid waste anaerobic digester effluent, agricultural anaerobic digester effluent, municipal wastewaters, agricultural wastewaters, and other similarly contaminated wastewaters.

Abstract: A method for removal of ammonia from a polluted medium avoids the disadvantages related to the chemical-physical properties of an ammonium-containing salt (MAP). The method has improved technical and economical operational parameters and produces a reusable and environmentally friendly nitrogen fertilizer. All chemical processes and mechanical steps of the method are carried out in one single container, with the different steps divided into time phases. The chemical products are prevented from transportation between compartments and contact with pumps and pipes. Only liquids without precipitates are in contact with these elements. The method is applicable to ammonia-containing water from leachate, wastewater, the food industry, and agriculture.

Abstract: Disclosed is a system for treating wastewater. The system includes a microorganism clad structure positioned in a body of wastewater such that the microorganism clad structure is at least partially submerged in the body of wastewater. The apparatus also includes an aeration device, such as a propeller-type, surface mounted aeration device, supplying a horizontal flow of oxygenated water to the microorganisms attached to the microorganism clad structure such that the microorganisms may carry out a biological process.

Abstract: A wastewater treatment system comprising one apparatus (1) for de-nitrification and effluent solids removal, another apparatus (2) for biological main treatment, and a further apparatus (3) for solids removal (5), each apparatus including a volume (40) in which each process is performed, a media-retaining sieve (6) at the volume (40) and arranged to retain buoyant media particles (4) in the volume (40), and a gas sparging device (8), (9) which is located in a lower end region of the volume (40) and which is controllable by way of valves (11) and (15). The three volumes (40) are substantially (10) identical to, or multiples of, each other, the three sieves (6) are substantially identical to each other, and the three sparging devices (8), (9) are substantially identical to each other. The gas is sparged into the main treatment bed at a lower flow rate for wastewater aeration but intermittently at a higher flow rate to disrupt and clean the bed.

Abstract: A wastewater treatment system includes wastewater having nitrogen-containing compounds, an anoxic zone having denitrifying bacteria, and an aerobic zone having nitrifying bacteria. The anoxic zone is coupled to the aerobic zone, and wastewater flows from the anoxic zone to the aerobic zone or vice versa. The wastewater treatment system is configured to accept heat from a heat engine to heat the wastewater. Treating wastewater can include flowing wastewater having nitrogen-containing compounds into a biological reactor having an anoxic zone and an aerobic zone, and heating the wastewater with heat from a heat engine to facilitate denitrification reactions in the anoxic zone and to facilitate nitrification reactions in the aerobic zone. In some cases, the wastewater is heated with a three phase fluidized bed heat exchanger having porous particulates in contact with heat exchange tubes, with bacteria coupled to an interior of the porous particulates.

Abstract: In a wastewater treatment plant using methane gas, a by-product of anaerobic sludge digestion, to generate energy in a combustor to run the plant, a system for collecting the gas stream from the plant biological process and feeding the gas stream, containing nitrous oxide emissions, into the combustor. The nitrous oxide is thermally reduced down to nitrogen (N2) and oxygen (O2).

Abstract: A method of biologically treating water and more particularly, a process for nitrifying and denitrifying water includes employing a continuous aeration mode and a sequential aeration mode. In the continuous aeration mode, nitrification and denitrification reactions occur simultaneously in the water. The continuous aeration mode occurs when the nitrate concentration of the water reaches a predetermined low threshold. The sequential aeration mode occurs when the nitrate concentration reaches a predetermined high threshold. When in the sequential aeration mode, aeration is ceased when the ammoniac concentration reaches a predetermined low threshold and aeration is activated when the ammoniac concentration reaches a predetermined high threshold.

Abstract: Disclosed is a system for treating wastewater. The system includes a microorganism clad structure positioned in a body of wastewater such that the microorganism clad structure is at least partially submerged in the body of wastewater. The apparatus also includes an aeration device, such as a propeller-type, surface mounted aeration device, supplying a horizontal flow of oxygenated water to the microorganisms attached to the microorganism clad structure such that the microorganisms may carry out a biological process.

Abstract: Described herein is a Submerged Attached Growth Reactor (SAGR) which provides nitrification (ammonia removal) from wastewater in cold to moderate climates. The system described herein is novel in that the SAGR reactor includes more than one influent distribution point. Specifically, in addition to the first influent distribution point at the front end of the reactor, there is provided at least one additional distribution point(s) downstream of this first distribution point for introduction of influent into the reactor. As a result of this arrangement, when a second low carbonaceous biochemical oxygen demand (CBOD), high nitrogen influent is distributed into the reactor at a location downstream of the initial influent entry point, a second (or more) population of bacteria (mainly nitrifying bacteria) is established and/or maintained in a physically discrete part of the overall treatment reactor.

Abstract: A process for the removal of azide ions from aqueous liquids at alkaline pH by alkali-soluble metals and catalyst or by hydrogen and catalyst.

Abstract: A bioretention system and method are provided for removing phosphorus, nitrogen and other materials from effluent such as wastewater and stormwater. The system and method can include a filtration media comprising water treatment residuals and other fill such as soil. Plants can be growing in the soil. The system can also include a drainage system to regulate outflow, to function during both low and high throughputs of water.

Abstract: A process for treatment of water to convert ammonia to nitrate including: feeding water containing dissolved ammonia, as an influent introducing water to be treated, into a packed column containing filter media as packing; introducing air through a diffuser at the bottom of the packed column to maintain the water saturated with oxygen throughout the packed column; establishing colonies of bacteria converting ammonia to nitrate within the column; and removing an ammonia-free and nitrite-fee effluent from the column.

Abstract: The present invention relates to a vertical-horizontal filter unit for the biological purification of polluted water, comprising an upper zone of a soil patch planted with plants, having inlets for the polluted water, and arranged underneath a sand layer with a lower filter zone made of gravel and at least one removal point for the purified water, wherein between the upper and lower filter zones a barrier layer with openings is arranged and the filter unit is sealed against the soil on the sides and at the bottom. The openings in the barrier layer are arranged along the edge and/or the barrier layer does not reach the edge of the patch completely. The invention is characterized in that the upper zone acts as an aerobically cleaning zone and the lower zone as an anaerobically cleaning zone.

Abstract: Improved fluidized bed precipitators (20, 46, 62, 74, 108, 112, 134, 168) especially useful for the treatment of waste waters containing soluble phosphorus are provided, having upright, primary fluidized bed sections (22, 48, 64, 76, 110, 114, 136) and obliquely oriented solids settling sections (28, 54, 68, 120, 144) which enhance the settling of small particles (166) and return thereof to the fluidized bed sections (22, 48, 64, 76, 110, 114, 136). The precipitators (20, 46, 62, 74, 108, 112, 134, 168) may also be equipped with a solids detection/withdrawal assembly (178) made up of one or more pressure transducers (180, 182) operable to determine the pressures within the fluidized bed sections 22, 48, 64, 76, 110, 114, 136) as a measure of bed densities, along with a selectively operable valve (172) which may be opened to periodically remove solids without clogging.

Abstract: A method for treatment of nitrified wastewater, the method including supplying wastewater to be treated to a tank having a layer of biomass supporting media near or at the top thereof, retaining biomass on and below the biomass supporting media for a sufficient time such that the biomass hydrolyses and supplies organic carbon to the wastewater in the tank; denitrifying and simultaneously clarifying the wastewater by providing an upward flow of the wastewater in the tank through the layer of biomass supporting media and discharging excess sludge from the bottom of the tank at a rate which is selected to maintain nitrate and ammonia concentrations below selected thresholds.

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: The present invention provides a treating unit of activated sludge for wastewater treatment and a treating apparatus having the same. The treating unit is constructed by a cage-shaped supporting structure which defines an interior space for containing the microbial cell therein. The present invention provides a measure for simultaneous removal of organics and nitrogen compounds from the wastewater under a condition of controlled aeration, and makes the configuration of treating apparatus as well as the treating process more simplified. It is also an alternative to replace the traditional A2O process. According to the present invention, the design of sludge return, which is essential for the conventional activated sludge treatment, is not needed. Moreover, the present invention is compatible with the conventional activated sludge treatment process and is advantageous in its short start-up period during which a stable operation is achievable.

Abstract: An aeration-less water treatment apparatus including an anaerobic reactor which receives sewage to cause the sewage to flow as an upward stream, and an aerobic reactor which receives treated water from the anaerobic reactor to cause the water to flow as a downward stream so that the water contacts aerobic microorganisms and air to aerobically treat the polluted matter in the water, the apparatus further including a suspended sludge section located in a lower part of the anaerobic reactor and in which the anaerobic microorganisms are suspended in the sewage, and a carrier section located in an upper part of the anaerobic reactor and having carriers to which the anaerobic microorganisms are attached, the anaerobic microorganisms having flowed from the suspended sludge section being further attached to the carriers.

Abstract: A method for treating a portion of liquid waste manure comprising adding a first reagent to the portion in a first vessel to cause the formation of waste manure flocs of a first size; adding a second reagent to liquid portion to cause growth of the waste manure flocs of the first size into separable waste manure flocs; adding optionally a third reagent to the portion of liquid containing waste manure flocs to cause further growth of the separable waste manure flocs; separating the liquid volume containing separable waste manure flocs into a waste manure sludge and a first filtrate; and dewatering the waste manure sludge in a filtration system comprising a first filter including a first housing, a first displaceable filter medium, and a first displacement actuator disposed between the first housing and the first displaceable filter medium.

Abstract: A process for treating nitrogenous wastewater contains an autotrophic denitrification reaction, a heterotrophic denitrification reaction and a COD removal reaction simultaneously and mixedly taking place in a single reactor. The nitrification reaction is caused by nitrifying bacteria, in which ammonium is oxidized into nitrite. The autotrophic denitrification reaction is caused by autotrophic denitrifying bacteria, in which ammonium used as electron donor and nitrite used as electron acceptor are converted into nitrogen gas and nitrate. The heterotrophic denitrification reaction is caused by heterotrophic denitrifying bacteria, in which nitrate and COD are consumed. It is not necessary to build two separate reactors for aerobic nitrification and anaerobic denitrification, thereby effectively reducing the fabrication and operation cost.

Abstract: In the treatment of domestic and municipal waste water environmental pollutants, such as ammonia, oxides of nitrogen, organic matter which gives rise to what is known as chemical oxygen demand (COD) [and biological oxygen demand (BOD)], and solid matter, should be removed from the waste water In a typical treatment process the waste water is treated to remove ammonia, firstly by nitrification—the biological oxidation of ammonia (NH3) to nitrite (NOD2?) and then to nitrate (NOD3?)—and, secondly, by de-nitrification—the conversion of the formed nitrite or nitrate to nitrogen gas (N2). Domestic and municipal waste water normally contains bacteria which will perform this treatment.

Abstract: Methods, systems and compositions for a green sorption media for bioretention soil amendments in drainfields for on-site waste water systems filled with the green sorption media to foster an anaerobic or anoxic environment saturated. The green sorption media includes one or more recycled materials, including tire crumb, sawdust, orange peel, coconut husks, leaf compost, oyster shell, soy bean hulls and one or more naturally occurring materials including peat, sands, zeolites, and clay. The wastewater filtration system for a passive drainfield includes the green sorption material mixture, a cell including baffled compartments and a riser, the cell filled with green sorption material mixture to provide an alternating cycle of aerobic and anoxic environments, an influent distribution system to distribute the influent over the cell, and a piping system arranged for dosing the cell to sustain the functionality of the green sorption material mixture to remove nutrient content in wastewater.

Abstract: The invention relates to a method for improving vermiculite's intake of ammonium, in which method heating of the crude vermiculite is conducted to a temperature where vermiculite's third dehydration step takes place, the temperature being lower than the temperature where vermiculite's fourth dehydration/dehydroxylation step takes place. The invention relates also to use of the obtained vermiculite and to an absorption material, comprising vermiculite material and additives, where at least 50% of the vermiculite material comprises vermiculite, which has undergone the third dehydration step but not the fourth dehydration/dehydroxylation step. The invention relates also to use of thermally treated and ammonium doped vermiculite as fertilizer/soil conditioner.

Abstract: A compact high efficiency combined biological and physical unsaturated wastewater treatment filter configured for periodic backwashing is disclosed. The filter utilizes packed media and removes pollutants and pathogens from wastewater and other dirty water sources. The filter comprises a periodic backwashing means to less the chance that biofilm growth will clog the media pores. However, such backwashing still leaves sufficient biofilm attached to the media to maintain a very high level of treatment. In the preferred embodiment, the filter utilizes high frequency dosing to cause pore saturation at or near the surface during dosing and shortly thereafter in order to maximize distribution uniformity and to induce downward airflow into the media. The system provides a number of unexpected benefits; including allowing a very low distribution pressure and providing high oxygen transfer at low energy utilization into the filter media for aerobic biodegradation of pollutants.

Abstract: An economical, integrated system works in series with anaerobic digestion of animal waste to recover nitrogen and phosphorous, while also scrubbing the produced biogas.

Abstract: The present invention relates to a novel arrangement of denitrification reactors for removal of nitrate compounds in a recirculating aquaculture system. The novel arrangement of an aquaculture system of the present invention includes positioning one or more anaerobic denitrification reactors upstream of aerobic nitrification and degassing processes. One aspect of the present invention includes a flow of aqueous medium from aquatic species rearing tanks towards one or more denitrification reactors. Another aspect of the present invention includes flow of aqueous medium from aquatic species rearing tanks to a solids removing filter or mechanical filtration means for removal of solid waste matter or biomass prior to flow of aqueous medium towards one or more denitrification reactors.

Abstract: Disclosed is a system for treating wastewater. The system includes a microorganism clad structure positioned in a body of wastewater such that the microorganism clad structure is at least partially submerged in the body of wastewater. The apparatus also includes an aeration device, such as a propeller-type, surface mounted aeration device, supplying a horizontal flow of oxygenated water to the microorganisms attached to the microorganism clad structure such that the microorganisms may carry out a biological process.

Abstract: A lagoon of effluent is established, comprising a set of sub-portions at different levels in the lagoon associated with a corresponding set of concentrations of dissolved oxygen, each sub-portion of the lagoon having a different concentration of dissolved oxygen. An incubator comprising a set of sub-portions associated with said set of concentrations of dissolved oxygen is established, each sub-portion of the incubator having a different concentration of dissolved oxygen. A volume of effluent from each sub-portion of the lagoon is transmitted to a corresponding sub-portion of an incubator having a substantially similar concentration of dissolved oxygen as said sub-portion of the lagoon. A first remediated volume of effluent is generated in said corresponding sub-portion of the incubator responsive to proliferating a first microorganism which uses a first compound in said volume of effluent as substrate for growth, the first microorganism enabling a first chemical reaction which alters the first compound.

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 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: The present invention provides a method of treating wastewater containing phosphorus and/or nitrogen for removing phosphorus and/or nitrogen from the wastewater, including following steps of: (a) introducing wastewater containing phosphorus and/or nitrogen into a an anaerobic reactor, treating the introduced wastewater with anaerobic microorganisms, to produce biogas from organic matters in the wastewater, and then discharging the treated wastewater saturated with carbon dioxide under carbon dioxide partial pressure of 0.2 to 0.5 atm; and (b) injecting the treated wastewater of step (a) into a carbon dioxide stripping apparatus wherein the wastewater is free-fallen to expose the wastewater to ambient condition with carbon dioxide partial pressure of less than 0.001 atm so that carbon dioxide stripping takes place and increase in pH occurs without addition of alkaline substance, and then providing proper pH of 8.4 to 9.6 to form struvite.

Abstract: A method for the removal and sequestration of ammonia nitrogen from anaerobic fermentation effluent while producing a higher BTU biogas. The method includes the steps of removing the slurry from the digester, stripping the ammonia from the slurry or portion thereof with a high BTU biogas, blending the stripped ammonia with the digesters biogas to remove the carbon dioxide and precipitate ammonium bicarbonate/carbonate as a solid while producing a high Btu biogas, a portion of which is used to strip the ammonia and CO2 from the slurry. The process removes ammonia nitrogen from the digester effluent while producing a high Btu biogas and a solid ammonium bicarbonate/carbonate product. Ammonia stripping is accomplished with a recycled stripping gas deficient in CO2 and ammonia that is capable of removing the CO2 and ammonia from solution by virtue of the lower partial pressures of CO2 and ammonia in the stripping unit.

Abstract: A bioretention system and method are provided for removing phosphorus, nitrogen and other materials from effluent such as wastewater and stormwater. The system and method can include a filtration media comprising water treatment residuals and other fill such as soil. Plants can be growing in the soil. The system can also include a drainage system to regulate outflow, to function during both low and high throughputs of water.

Abstract: An apparatus is provided that includes: a containment system 208 having at least one sidewall and bottom that are substantially impermeable to a passage of water; a distribution system 124 to introduce an aqueous stream comprising nitrates into the containment system; a de-nitrification system 128 comprising a de-nitrification media, the media being contained within the containment system; a pump to pressurize the stream and cause the stream to pass through the de-nitrification media, thereby converting at least most of the nitrates into nitrogen gas and forming a treated stream; and a collection system 132 to remove the treated stream from the containment system.

Abstract: The invention relates to a method for processing an aqueous effluent (E) containing in solution at least one type of metal (M) nitrite or nitrate whose oxide is stable in an aqueous medium consisting (I) in introducing cations NH4+ in aqueous solution, generally in the form of an aqueous ammonia solution, into the aqueous effluent and, subsequently (II) in processing the obtainable medium at a temperature ranging from 100 to 700° C. and a pressure of 1-50 MPa (i.e. from 10 to 500 bar), thereby converting the metal (M) nitrite or nitrate into metal (M) oxide, nitrogen and water.

Abstract: Biological nutrient removal (BNR) in wastewater treatment to remove carbonaceous substrates, nutrients and phosphorus, has recently become increasingly popular worldwide due to increasingly stringent regulations. Biological fluidized bed (BFB) technology, which could be potentially used for BNR processes, can provide some advantages such as high efficiency and compact structure. This present invention incorporates the fixed-film biological fluidized bed technology with the biological nutrient removal in a twin liquid-solid fluidized bed, which has achieved the simultaneous elimination of organic carbon, nitrogen and phosphorus, in a very efficient manner and with very compact space requirements. The BNR-LSFB has two fluidized beds, running as anoxic/anaerobic and aerobic processes to accomplish simultaneous nitrification and denitrification and to remove carbonaceous substrates, nutrients and phosphorus, with continuous liquid and solids recirculation through the anoxic/anaerobic bed and the aerobic bed.

Abstract: A constant velocity serpentine anoxic reactor incorporates a multiple cell vertical serpentine path, as well as a horizontal serpentine path, through the anoxic chamber. A fixed film media is mounted within each cell of the anoxic chamber to provide a structure on which the bacteria can grow to sustain the biological reaction, which convert nitrates into nitrogen gas. The fixed film media can be a cross-flow media and can optionally include a web of textile material integrated within the fixed film media to enhance bacterial growth within the fixed film media or optionally the anoxic vertical serpentine configuration could be applied to an activated sludge operation. A nitrate recycle pump recycles about 75% of the effluent from the aerobic chamber back into the anoxic chamber to provide a nitrate source for the digestion of the BOD within the influent wastewater.

Abstract: The invention is directed to a process for the simultaneous removal of BOD and phosphate from a liquid containing ammonium, BOD, phosphate and magnesium, the method comprising: feeding the liquid to a reactor containing BOD-oxidising biomass; ensuring that the liquid in the reactor contains an excess to stoichiometry of ammonium and magnesium relative to phosphate, wherein the stoichiometry is related to the stoichiometry of struvite; oxidising at least part of the BOD; adjusting the pH of the liquid in the reactor at a desired value; forming solid material in the reactor, the solid material comprising struvite; separating at least part of the solid material from the reactor effluent; returning a part of the solid material to the reactor. The invention is also directed to a reactor for this process. The advantage of the process and the apparatus is that in one reactor both BOD and phosphate are removed from the liquid.

Abstract: A process for treating biological oxygen demand (BOD), nitrogen and phosphorus containing wastewater, wherein the process includes providing wastewater influent to an oxygen-deficit aeration zone having activated sludge and mixing the wastewater influent with the activated sludge in the oxygen-deficit aeration zone to form a mixed liquor. The process further includes transferring the mixed liquor from the oxygen-deficit aeration zone to an oxygen-surplus aeration zone and transferring a portion of the mixed liquor from the oxygen-surplus aeration zone to a membrane filter wherein a filtrate is separated from sludge. In addition, the process includes recycling at least a portion of the sludge to the oxygen-deficit aeration zone as recycled activated sludge.

Abstract: Method and apparatus in which a biomass is carried on a substrate that is fluidised. The fluidised substrate has a layer of distributor particles below it, through which the fluidizing medium passes prior to contact with the fluidised substrate and biomass associated therewith. The effect of the distributor layer is that the particles damp out excessive turbulence in the fluidizing medium, thus preventing undue turbulence of the medium within the fluidised layer. The particles may be recycled through the distributor layer to strip excess biofilm from the substrate particles prior to returning the substrate particles to the fluidised bed.

Abstract: A method of supporting denitrification includes receiving biological material at a pulsed electric field station and applying a pulsed electric field to the biological material within a treatment zone in the pulse electric field station to generate treated biological material. The method also includes transporting at least a portion of the treated biological material to an anoxic bioreactor in substitution, at least in part, for an external source of electron donor. A system for supporting denitrification is also provided.

Abstract: Disclosed is a system for treating wastewater. The system includes a microorganism clad structure positioned in a body of wastewater such that the microorganism clad structure is at least partially submerged in the body of wastewater. The apparatus also includes an aeration device, such as a propeller-type, surface mounted aeration device, supplying a horizontal flow of oxygenated water to the microorganisms attached to the microorganism clad structure such that the microorganisms may carry out a biological process.