Abstract: In a method for backwashing a water processing system using a buoyant filter layer constrained under wire mesh screen extending across a processing vessel, a water surface level in the processing vessel is lowered below the wire mesh screen. Air is subsequently released from under the buoyant filter layer to separate substances clogging the filter layer, while allowing the release of air out of said vessel from an upper part thereof. By lowering the water surface level below the upper wire mesh screen, the filter material is allowed to move more freely because the filter material is not restricted by the wire mesh screen from making upward movement. Hence, when air is released from under the filter layer, the filter material can move uniformly over the entire filter layer, and the clogging substances such as SS captured by the filter material and the biological film formed on the surface of the filter material can be favorably removed without damaging the filter material.

Abstract: A method of treating a waste stream including the steps of feeding the stream through a thermophilic anaerobic reactor and then a mesophilic anaerobic reactor operated in series.

Abstract: An aquarium filter for removing chemical and physical waste from an aquarium. The filter includes a fluidized bed of particles, such as sand, for removing ammonia from the water. The filter can also include a physical trap for solid material and activated charcoal for removing organic material from the aquarium water. The filter can be constructed in an aesthetically desirable manner and can be convenient to maintain.

Abstract: A process and apparatus for the treatment of flowable waste in a waste treatment reactor and in particular the treatment of waste water in a bioreactor containing a bed of support particles having an attached biofilm and entrapped microorganisms are described. The process includes the steps of intermittently introducing waste water through a discharge port adjacent a bottom surface of the bed to form a series of plugs of waste water integrated with the microorganisms in the immediate vicinity of the discharge port; and maintaining a quiescent period following each introduction of waste water to promote biological degradation of contaminants in the waste water of each plug by the microorganisms and production of treated waste water.

Abstract: A wastewater treatment process having improved solids separation characteristics and reduced biochemical oxygen demand (BOD) in the purified wastewater comprising the steps of: passing wastewater containing suspended solids and biodegradable organic substances through a main aerobic biological oxidation zone and therein oxidizing a portion of the BOD and converting a portion of the BOD into additional suspended solids and at least a portion of the ammonia nitrogen content (NH.sub.3 --N) of the wastewater is oxidized to nitrate nitrogen (NO.sub.

Abstract: A water treating apparatus is provided which can treat waste water for use as raw water in an ultrapure water producing system without addition of various kinds of chemicals. The apparatus includes a first water tank for receiving acid waste water, a second water tank for subjecting the waste water from the first water tank to solid-liquid separation and discharging supernatant liquid, an ion exchange tank including ion exchange resin and an aeration tube for generating treated water through a membrane filter, a precipitation tank for settling ion exchange resin, an air lift pump for introducing ion exchange resin from the precipitation tank into the first water tank, and a return air lift pump for returning ion exchange resin from the second water tank to the ion exchange tank. The ion exchange resin acts to exchange ions with fluorine ions of treated water in the ion exchange tank and is regenerated by acid waste water in the first water tank.

Abstract: The treatment system is for use with septic tank effluent. Water is passed over polyurethane foam blocks, arranged in a heap so that air can circulate freely around the blocks. The size of the foam cells is small enough that water soaks into the blocks and is retained therein. The foam is soft and easily deformed. At the points of block-to-block engagement, the blocks deflect and conform to each other, giving rise to a large contact area through which water can pass between blocks.

Abstract: A radial flow bioreactor comprising a reaction vessel having an inlet and an outlet respectively for adding and withdrawing a culture medium and at least one cell basket within the reaction vessel for accommodating a plurality of cell carriers and having side wall perforations so dimensioned as to prevent passage of the cell carriers therethrough.

Abstract: Biological denitrification of water using one or more bioreactor units containing bioreactor media, a prefilter assembly containing prefilter media, and a slow sand filter containing sand filter media. Each bioreactor unit requires certain water flow related values and the bioreactor media must have certain material or dimensional characteristics. An air scouring process is constrained to predetermined parameter values to remove excess biomass material from the bioreactor media. The prefilter assembly also includes a flow distribution device for providing uniform water flow throughout the cross-section of the prefilter media. In one embodiment, the prefilter assembly and the slow sand filter assembly are semi-portable in that they have a reduced size with limited dimensions. This enables the prefilter assembly and the slow sand filter assembly to be made at a remote location and transported to the site at which water is to be denitrified.

Abstract: The present invention provides a high-performance organic waste water treating system which allows continuous processing of waste water without causing deterioration of the performance due to clogging of the filtration bed, excessive sludge, bad smell, or breeding of flies. The system of the invention includes a trickling filtration bed packed with filter media having a particle diameter of not greater than 10 mm, the filtration bed comprising an upper portion, a middle portion, and a lower portion, an air supply unit for feeding air from a bottom of the filtration bed to make the air flown through the filtration bed, and a vent pipe embedded into the middle portion of the filtration bed to connect to the atmosphere. A predetermined amount of organic waste water is abruptly supplied over a short time period into the trickling filtration bed at a predetermined cycle.

Abstract: The apparatus for waste water treatment has, in a tank, a contact circulation part in which Bincho charcoal is accommodated, a sprinkling circulation part which is disposed above the contact circulation part and in which black coal is accommodated, air lift piping for lifting treatment-object water from the contact circulation part to the sprinkling circulation part, a water-sprinkling tube for sprinkling the treatment-object water onto the sprinkling circulation part, an aquatic plant cultivation bed disposed between the contact circulation part and the sprinkling circulation part, and air-diffusing tubes for introducing malodorous gas. Small quantity of surfactants and colorants are adsorbed by the Bincho charcoal and the black coal and decomposed by microorganisms that have grown in the Bincho charcoal and the black coal. The microorganisms act to biologically decompose the malodorous gas.

Abstract: An anaerobic digestion process capable of converting organic slurries to precipitates, as well as soluble and gaseous products through a series of reactors or process steps. The organic material is processed through three sequential steps consisting of two anaerobic digestion steps and an intermediate liquid/solid separation step. The sequential steps consist of first degrading rapidly metabolized soluble and particulate constituents, contained in the influent, by mixing the influent to the first reactor with an effluent from a second reactor containing a high concentration of active biomass. Effluent from the first reactor is treated in a second step wherein the soluble and particulate components are mechanically separated from an effluent stream essentially free of particulate material but containing soluble products of digestion.

Abstract: A multistage treatment system for treating nutrient-rich water containing nitrogen compounds, phosphorous compounds, and other minerals. Three or more vessels or stages typically constitute the multistage treatment system. Each stage of the system is a reaction vessel having a first zone containing a substantially insoluble salt for precipitating phosphorous compounds and other minerals, a second zone containing a microorganism retained on an inert substrate for converting nitrogen compounds, and a separation device for removing precipitates from the water. The effluent from the multistage system may be further treated in ponds cultivated with aquatic grass or in a packaged algae filter having a medium for supporting algae growth and an artificial light source.

Abstract: Process and plant for biological purification of polluted water wherein the polluted water is successively subjected to an anaerobic, anoxic and aerobic treatment in the presence of microorganisms, and wherein the anaerobic and the anoxic treatment are carried out in the presence of one or more microorganism cultures which are different from the microorganism culture used in the aerobic treatment. Hereby better exploitation of organic matter in the water is obtained thus improving the removal of nitrogen, and an increased reaction rate per unit mass of biomass is obtained thereby allowing the amount of biomass to be reduced or the total reaction rate of the plant to be increased.

Abstract: Organic contaminants are removed from water by microbial biodegradation in a stirred tank system having a powdered or granular media for biofilm support. A stirring impeller maintains the media suspension, provides a shear force to remove excess biomass from media particles and is adjustable to provide an optimal biofilm thickness.

Abstract: A process and a device for biologically treating an organic waste mixture containing organically polluted waste water and solid components. The process and the device involve exposing the organic waste mixture to a first decomposition stage where the solid components and the waste water are separated from one another and where the solid components are decomposed under predominantly aerobic conditions. The waste water is then passed to a second decomposition stage where the waste water is decomposed under anoxic conditions. Thereafter, the waste water is passed to a third decomposition stage where the waste water is decomposed again under aerobic conditions thereby creating recirculation water. At least a portion of the recirculation water is returned from the third decomposition stage to the first decomposition stage for continuously recirculating water through and between respective decomposition stages.

Abstract: A method for complete treatment of septic tank effluent or other contaminated liquid by contriving for it to flow in an ultra-thin film over a surface treatment medium such as fabric or sand. It provides diffusive aeration, biological reaction and physical filtration on a molecular scale.The device transfers contaminated water, or other liquid, from a container to a final collector completely purifying the liquid in the process. The purified effluent can then be reused for household, industrial, irrigation or other uses, or disposed of as normal surface run-off in streams or lakes.To increase efficiency, said container encloses a progressively more finely pored media precisely situated with effluent seeping gradually through progressively finer pores to provide uniquely effective pretreatment.

Abstract: Organic waste disposal treatment apparatus includes a treatment chamber assembly in which a compost bed may be formed, an inlet to the treatment chamber assembly through which organic waste may be added to a compost bed in the treatment chamber assembly, ventilation means for promoting aerobic digestion of the compost bed in the treatment chamber assembly, drainage means for preventing waste material in the treatment chamber assembly from becoming anaerobic and access means for accessing and removal of compost formed in the treatment chamber assembly. The treatment chamber assembly includes a holding tank formed of plastics material, the access means includes a closed conveyor for conveying compost from the lower zone of the compost bed. The treatment chamber assembly may include an air permeable division for diving a duct from the compost bed. It is also preferred that the holding tank be partially filled with an active bed of compost.

Abstract: A process for maintaining a high rate of mass transfer of nutrients contained in a liquid feed stream to a biofilm of microorganisms supported on a bed of particulate matter. The microorganisms in the biofilm are subjected to a continuous, uniform flow of the liquid feed steam and a countercurrent flow of respiratory air so as to support biofilm growth. The bed is periodically pulsed with air at a pressure sufficient to shed microorganisms from the biofilm, and at intervals sufficient to avoid preferential channeling of the liquid feed steam through the bed and/or to disrupt and rearrange the bed of particulate matter.

Abstract: A fluidized-bed fermenter is described, which is characterized by an inverted cone-shaped fermentation space (1) with two feed pipes (2 and 3) optionally provided with control valves (4 and 5), of which one (2) is vertically aligned to the cone vertex and the second (3) is nonvertically aligned to the shell of the cone in 0.1 to 0.3 times the height of the fermentation space and a sedimentation space (6) above fermentation space (1), which has one or two drainpipes (7 and 8) optionally provided with control valves (9 and 10).

Abstract: A filtration system for an aquarium having water and fish. A container is mounted in juxtaposition to the aquarium and a porous filter is disposed in the container. The top of the filter is connected to the bottom of a pot in which is growing a terrestrial plant in soil. A pump circulates water from the aquarium into the container and through the filter. The filter removes solid and dissolved pollutants from the water and roots of the plant grow into the filter, utilizing the pollutants retained in the filter.

Abstract: The invention relates to a method for removing hydrogen sulphide (H.sub.2 S) from oil-containing water and equipment therefor. Oil-containing water and nitrate is conducted through a bioreactor to remove H.sub.2 S. Nitrate is added to the oil-containing water in a dose ratio (sulphide:nitrate) of 1:10 to 1:40. The retention time in the reactor tank is 10-60 minutes. After this treatment, purified water where >90% of the H.sub.2 S-amount is removed are taken out of the tank. The equipment for performing the method is based on a bioreactor having a large density of denitrifying bacteria. The reactor tank 1 is filled with carrying material providing large contact area. Even distribution of oil-containing water and nitrate over the carrying material which already may be covered by septic mud, forms an active sulphide oxidizing biofilm having a large surface. This biofilm is extremely effective for removing sulphide from oil-containing water.

Abstract: An integrated synchronous aerobic/anaerobic bioreactor is disclosed for treating waste liquids, such as pulp and paper waste water, and to methods of treating such waste liquid. The apparatus includes a bioreactor and an external aerator for injecting a controlled amount of an oxygen-containing gas into the waste liquid as it is cycled through the apparatus. An aerobic/anaerobic biofilm is provided in the reactor, having a decreasing gradient of oxygen concentration toward its core.

Abstract: Removal of a target metal having an insoluble phosphate (e.g. actinides), is effected by passing the solution through a bioreactor containing an immobilised phosphatase-producing microorganism which has been cultivated using a culture medium containing an assimilable organic source of phosphorus and which has been primed with an element, other than the metal to be removed, having an insoluble phosphate so as to deposit the phosphate of the priming element on cell surfaces of the microorganism. The priming element phosphate facilitates deposition of the target metal phosphate.

Abstract: A biofilter for the removal of contaminants from gas streams disclosed. The biofilter makes use of a series of modular trays, each containing a gas-contacting medium for removing at least one contaminant from the process stream. The trays have a modular design that allows them to be sealingly stacked and to be configured to allow series, parallel or series-parallel flow through the biofilter.

Abstract: A reactor for treating a liquid containing evolvable and entrained gas has a vessel for containing a bed of particulate media, and a liquid flow distributor mounted in the vessel that includes a manifold connected to receive liquid and introduce it into the bed. The manifold includes a liquid conveying passage having an upper region where any gas that evolves from the liquid can collect and at least one discharging nozzle having an inlet in open communication with the upper region for receiving the liquid, evolved gas or a mixture thereof, and an outlet for uniformly discharging the liquid, gas or mixture thereof into the bed.

Abstract: A method of treating waste water is described. Firstly, providing specially acclimatized microbial consortia with relatively low sensitivity to changes in pH and changes in temperature, such that the microbial consortia is capable of metabolizing contaminants efficiently within a predetermined broad pH range and broad temperature range. Secondly, maintain the microbial consortia in a space limited and a substrate limited mode within an immobilized bioreactor operating within the predetermined pH range and the predetermined temperature range. Thirdly, introduce waste water with liquified insoluble organic contaminants into the immobilized bioreactor. The organic contaminants are metabolized by the microbial consortia working under space limited and substrate limited conditions, thereby treating the waste water with a minimal sludge production rate.

Abstract: To purify untreated water, for example waste water, containing organic pollution, materials in suspension and nitrogen-containing pollution, reagents are added under conditions adapted to coagulate all of the materials in suspension, including colloidal materials, to form granular physical/chemical floc. Diluting water is added, preferably after the reagents, in a flowrate ratio of at least 2/1. The dilute flocculated water is caused to flow through a bed of sludge in the form of such dense and granular floc and denitrifying bacteria. The bed is subject to turbulent but intermittent agitation. A denitrified effluent is recovered. This denitrified effluent is caused to flow through a biological filter or preferably through a fluidized bed containing nitrifying bacteria and into which oxygen or air is injected. A clarified effluent is obtained, some of which is recycled as the diluting water.

Abstract: An apparatus for waste water treatment, wherein fluorine contained in waste water is treated into a fluoride through a chemical reaction and sludge containing the fluoride is thickened and dehydrated into a sludge cake, has first and second tanks each packed with calcium carbonate mineral. In the first tank, waster water containing fluorine is agitated by air discharged from an air diffuser and caused to react with the calcium carbonate mineral. Through this reaction of the waste water with the calcium carbonate mineral and action of microorganisms on the surface of the calcium carbonate mineral, a pH value and a fluorine concentration of the waste water is adjusted till the pH value and the fluorine concentration fall within their respective predetermined ranges.

Abstract: A waste water treatment apparatus is provided which can treat a high-concentration waste water containing persistent chemical substances including nitrogen and surfactant simultaneously with small amount of exhaust gases and is yet simple in construction. The apparatus has a first bioreactor having a lower portion including an inflow pipe for admission of waste water to be treated and aeration means, and an upper portion packed with vinylidene chloride fillers; a second bioreactor including a filler-packed portion packed with charcoal and calcium carbonate fillers; and an exhaust gas introduction diffuser for directing exhaust gases generated in an uppermost portion of the first bioreactor into the filler-packed portion. The water under treatment is anaerobically treated in the lower portion and is subjected to aerobic treatment and also to anaerobic treatment in the upper portion.

Abstract: A method and apparatus for achieving in situ bioremediation of volatile contaminants in the vapor phase and dissolved or dispersed contaminants in the groundwater phase at a contaminated site. The apparatus of this invention is configured to be used within a remediation well of the type employed with vapor extraction and dewatering techniques, and serves to biologically treat soil contaminants in situ with microbes and any suitable microbial nutrients. As such, the present invention is adapted to be employed in conjunction with vapor extraction and dewatering remediation techniques to treat vapor and water-borne contaminants more effectively. The apparatus securely retains the microbes in a manner that serves to prevent leaching into the surrounding soil while simultaneously protecting the microbial population from predatory, competitive and inhibitory microorganisms.

Abstract: A biological purification process, a secondary treatment of partially cleaned waste water for example, is carried out in a porous bed of loose granules which float in the liquid. The granules are continuously washed to remove coagulated impurities by means of a small quantity thereof being entrained from the top of the bed in a small volumn flow of the effluent of the process, mixed with the inflowing impure liquid and then returned to the bottom of the bed. Excess reaction gas may also be delivered to the bed via the inflowing liquid and unreacted gas collected for reuse.

Abstract: Porous bodies are produced which are suitable for use as supports for catalysts, including living cells, such as bacteria and which are upset resistant to acids and bases. The bodies have a significantly large average pore diameter of about 0.5 to 100 microns, (i.e. 5,000 to 1,000,000 .ANG.) and a total pore volume of about 0.1 to 1.5 cc/g with the large pores contributing a pore volume of from about 0.1 to 1.0 cc/g. The bodies are made by preparing a mixture of ultimate particles containing a zeolite and one or more optional ingredients such as inorganic binders, extrusion or forming aids, burnout agents, or a forming liquid, such as water. In a preferred embodiment, the ultimate particles are formed by spray drying.

Abstract: A process and system for the reduction of nitrate to nitrogen in a fluid medium. Anaerobic bacteria fed by a carbon source are used for nitrate reduction. The addition rate of the carbon source and process residence time are controlled using the oxidation-reduction potential of the fluid medium to achieve a desired level of nitrate reduction. An industrial process control system may be used to monitor inputs and control outputs. A column of suspended beads may be used as the anaerobic bacterial bed for denitrification.

Abstract: The present invention features methods and apparatus for biodegrading pollutants carried by aqueous fluid. The method and apparatus use a vessel and a matrix for immobilizing microorganisms and an inlet and outlet opening for creating a horizontal flow of fluid and air through the matrix. Microorganisms immobilized on the matrix biodegrade pollutants.

Abstract: Disclosed herein is a treatment facility comprising a fluid bed reactor including a reactor tank containing a bed of particles which function as a carrier for growth of biological material, the reactor tank having an inlet and an outlet, the reactor further including structure for conducting liquid to be treated, from the reactor tank inlet, upwardly through the bed of particles at a rate conducive to fluidization of the bed of particles; an equalization surge tank for housing liquid to be treated in the fluid bed reactor, the equalization surge tank having an inlet, and an outlet; conduit structure for supplying liquid from the outlet of the equalization surge tank to the inlet of the fluid bed reactor; and structure for supplying an oxidant into the equalization surge tank, in such a manner that stripping of volatile constituents is avoided, for oxidizing iron in the liquid in the equalization surge tank.

Abstract: A method and an apparatus for in situ purification by aeration and biofiltration of water from a water body. According to this method, polluted and/or oxygen deficient water is drawn through a conduit into a submerged chamber held adjacent to the surface of the water body. Water is oxygenated from three sources: air injected into the conduit to draw the water into the submerged chamber, air diffusing from the surface of the water body; and air injected in a lower portion of the chamber. The oxygenated water flows downwardly from the chamber through a submerged biofilter having a filter bed made of filtering media which may be preinoculated with beneficial microorganisms and essential nutrients. Rafted or floating vascular plants can be inserted into the chamber to enhance purification by fixing metals.

Abstract: A method for treatment of a liquid waste stream having an undesirably high COD and comprising water and a concentration of organic nitrogen compounds of at least about 300 mg/l total kjedahl nitrogen is disclosed. According to the method, the liquid waste stream is oxygenated to produce an oxygenated liquid containing water, dissolved oxygen and the organic nitrogen compounds and the oxygenated liquid is passed through a fluidized bed reactor containing a fluidized bed of particulate solids supporting microorganisms capable of biodegrading the organic nitrogen compounds, thereby to subject the organic nitrogen compounds in the oxygenated liquid to aerobic microbial degradation and to produce an effluent containing water, ammonia and carbon dioxide, and the fluidized bed reactor contents and the effluent is maintained at a pH in the range of from about 6 to about 8.

Abstract: A liquid treatment apparatus for removing potentially combustible substances from water includes a biological fluid bed reactor that is supplied by a first conduit with contaminated water and that treats this water, under aerobic conditions, before discharging it as treated effluent containing a significantly reduced concentration of contaminants. The liquid treatment apparatus also includes a gas dissolution apparatus for providing dissolved oxygen to the contaminated water flowing through the first conduit to sustain biological action in the reactor. The gas dissolution apparatus includes an oxygenator including a pressurized bubble contactor disposed in a recycle conduit connected between the outlet of the reactor and the first conduit.

Abstract: A method of improving the quality of septic tank effluent is disclosed. Sewage wastewater having a significant concentration of waste solids is flowed to a septic tank. In the septic tank the solids are allowed to separate from the wastewater to form a relatively clear horizontal liquid layer between sludge and scum layers. At least a portion of the liquid layer is flowed from a recirculation outlet through an aerobic filter to produce a filter effluent. The filter effluent is flowed to the septic tank. A septic tank effluent is discharged from a septic tank discharge outlet which is spaced apart from the inlet and which is in fluid communication with the liquid. The septic tank effluent has reduced levels of total nitrogen, BOD and total suspended solids.

Abstract: A method of treating a waste stream including the steps of feeding the stream through a thermophilic anaerobic reactor and then a mesophilic anaerobic reactor operated in series.

Abstract: Apparatus (1) for treating a fluid, in this case wastewater, comprising a vessel or tank (2), a conduit (3) to supply the wastewater in an alternating sequence to the vessel (2), and a source (4) for oxygenating the bed of granular media (5) to provide aerated filter media. The filter bed is aerated during operation by air, oxygen enriched air or other gas being introduced at or adjacent the base (as viewed) of the bed through the source (4), which may be a perforated manifold, diffuser or the like extending substantially over the whole surface area of the bed (5). Also, the bed (5) is a granular media such as natural minerals or blast furnace slag media to the surface of the discrete particles of which is attached bacteria and microorganisms (a biomass) which effects treatment of the fluid.

Abstract: A bioremediation support for the support of microorganisms used in the biotreatment of an aqueous waste stream or contaminated vapor is made of a low-density siliceous glassy material. This material has a cellular or frothy texture, large pores of greater than 1,000 Anstrom units in diameter dispersed throughout the material, a high macropore volume in pores of greater than 1,000 .ANG. of more than 0.3 cc/cc and a BET surface area of greater than 10 m.sup.2 /g. A preferred material is pumice.

Abstract: A device and method for maintaining effective bacterial levels within a collecting container of an organic matter collection system of the type having a collecting container having a bottom and a liquid to air interface-surface is provided. The bacterial incubator comprise: a housing having a first and second interior chamber; an elongated feed tube, connected to the housing, having a passageway terminating at one end in connection with the second interior chamber and terminating at the other end in a feed opening; and a plurality of high surface-area members that are contained within the first interior chamber. The first interior chamber is in fluid connection with both the second interior chamber and the exterior of the housing. The elongated feed tube is of a length sufficient to allow a section thereof containing the feed opening to be positioned above the air to liquid interface-surface of a collecting container.

Abstract: A filter system is provided for mounting on an aquarium tank to treat the water in the aquarium. The filter system comprises a plurality of filter chambers, each containing a different filter media. The filter chambers serve to filter particulate matter from the aquarium water. A heater is further provided for controlling and maintaining the temperature of the aquarium water. The filter system further includes a dry chamber including a biological medium to support the growth of beneficial bacteria on the medium. A particularly preferred type of media is a plurality of plastic biospheres. The beneficial bacteria serve to biologically treat the aquarium and eliminate ammonia and nitrites from the water. At least one buffering chamber including a buffering medium is provided for buffering the aquarium water and maintaining a predetermined alkalinity level for the water. An air pump serves to pressurize portions of said filter system and aerate the aquarium water.

Abstract: A system for treating groundwater contaminated with acidity or other contaminants is disclosed. The system involves excavating a trench into the aquifer in the path of the contaminant plume, and placing a body of active material in the trench. The active material depends on the particular contaminant: organic carbon may be used when the contaminant is ferrous sulphate, or hexavalent uranium oxide, or dissolved nitrate; pyrite or elemental iron may be used when the contaminant is eg chromium oxide. The active material causes the contaminant, by chemical reaction, to change its oxidation-reduction state, and to precipitate harmlessly in the body of material.

Abstract: A treatment zone 10 in the form of a basin 12 having an inlet port 14 and an outlet port 16. The inlet port 14 allows water to flow into the basin 12. The outlet port 16 allows water to flow out of the basin 12. The inlet port 14 and the outlet port 16 are located at opposite ends of the basin 12 so as to allow water from a body of water having a concentration of water soluble metal ions contained therein to flow substantially through the entirety of the basin 12. A porous matrix 22 is disposed within the treatment zone 10. The porous matrix 22 is inoculated with a population of aerobic metal oxidizing bacteria. The population of aerobic metal oxidizing bacteria is capable of metabolizing water soluble metal ions in the water from the body of water into water insoluble metal oxides. Thus, there is an overall decrease in the concentration of the metal ions in the water flowing out of the treatment zone 10 as compared to water flowing into the treatment zone 10.

Abstract: This invention relates to a method and apparatus of denitrification. The apparatus includes a weir block, a denitrification vessel having a wall surface, and filter media having microorganisms on their surfaces. The weir block may have a convex outer surface which is tangentially adjacent to and preferably contiguous with the upper end of the wall, whose lower end is in contact with the water in the denitrification vessel. The method may include passing the wastewater over the convex surface of the weir block, passing the water over the second surface of the substantially vertical wall and into the denitrification vessel while preferably maintaining substantially laminar flow and limiting the dissolved oxygen in the denitrification vessel, preferably to below about 5 mg/L and more preferably to below about 4 mg/L.

Abstract: An ecological fluidized bed system and method for the processing of polluted water to provide treated water. The system comprises a fluidized bed container containing a layer of coarse media with a layer of fine media above it which has a buoyancy substantially similar to the polluted water, and particularly pumice rock having a high surface to volume ratio, an inlet to introduce water into the container, and an outlet to withdraw treated water, and either a mechanical pump in an anaerobic operation or an airlift pump in an aerobic operation. The system includes an ecosystem such as microorganisms, benthic animals, and higher aquatic plants for the purification of the polluted water within the container, and a pump means to provide for the rapid recirculation of the polluted water within the container with the fine media as a fluidized bed, with a recirculation rate up to a thousand times the flow-through water rate, thereby providing for the rapid, efficient and effective purification of the polluted water.

Abstract: Process for the biological treatment of water using a biological reactor containing a culture of microorganisms, immobilized on a granular support material, according to which an expendable powdery material is injected into the said reactor, said process being performed so as to ensure a self-selection and a self-regulation of the support material of the particle size necessary for the biological process.