Abstract: The present invention relates to a process for the purification of a medium containing organic waste. The process according to the present invention is characterized in that the starting medium (or effluent) containing the organic waste is subjected to the following stages: (i) treatment with at least one oxidizing agent; (ii) treatment with at least one flocculating agent; (iii) treatment with at least one polyelectrolyte, and in that the effluent obtained on conclusion of all of these stages is subjected to a filtration stage (iv), whereby a filtration cake and a filtrate are obtained. The process according to the present invention is more particularly useful for the treatment of pig manure.

Abstract: A method and plant for the purification of polluted water by the activated sludge method is provided in that a mixture of polluted water and recycled sludge is subjected to biological treatments in at least two treatment zones, and maintaining for a period such conditions in one of the treatment zones that a sludge precipitation occurs therein, supplying in a subsequent period the mixture of polluted water and recycled sludge directly or indirectly to the zone which, during the preceding period, served as a sludge precipitation zone prior to further treatment thereof in one or more treatment zones, and passing the treated water to a permanent clarification zone and separating it into a water fraction and a sludge fraction, at least a part of the sludge fraction being recycled and mixed with polluted water.

Abstract: A method of purifying waste water biologically, in which at least one biological reaction is performed in at least one biological reactor containing microorganisms in activated sludge, and the waste water is separated from the activated sludge in a clarification basin, with at least a fraction of the activated sludge from said biological reactor being recirculated, wherein, prior to admitting the waste water to be treated into said biological reactor, at least a fraction of the polluting particles in suspension therein are separated out therefrom, the separated polluting particles are sent to a sludge activation reactor that is separate and disposed in parallel, the separating polluting particles are used as the main substrate for the development of microorganisms in strict aerobiosis, and the superactivated sludge obtained in this way is injected into the biological reactor(s).

Abstract: Methods and compositions are disclosed for treating swimming pool waters in order to remove one or more nutrients necessary for algal growth and to accelerate the breakdown of objectionable chloramines within chlorinated pool waters. The target nutrients of preference are those containing phosphorus or nitrogen. Phosphorus nutrients are preferably removed by ion-exchange with finely divided lanthanum carbonate, or by direct precipitation in the pool with liquid lanthanum chloride. Nitrogen nutrients (including, in particular, chloramines) may be removed (possibly with the aid of catalysts and in separate reactors). The same reagents used to scavenge phosphates are useful in this regard, the nitrogen being released from the pool water as a nitrogenous gas. To allow the fine lanthanum carbonates to be conveniently handled in the pool environment, they may be linked to larger carrier particles, such as those of diatomaceous earth, or they may be embedded within porous beads formed from polymers or gels.

Abstract: The metal oxide media includes oxides and hydroxides of iron, and other metals. The material is derived from basic-oxygen steel-making process, and includes a high calcium content. The oxide surfaces facilitate the adsorption of phosphorus, and the increased pH facilitates the precipitation of calcium and other phosphates. The oxides are a catalyst for converting organic phosphorus to inorganic form. Limestone may be added to the oxides, to ensure a long-term source of calcium, and to maintain high pH for long periods.

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

Abstract: The biological process is for treating wastewater in order to remove the phosphorus therefrom and thus obtain clarified water. The process is using two sequencing batch reactors (SBR) in series filled with a sludge-mixed liquor. The process consists of: continuously feeding wastewater into the first (SBR) operating under anaerobic conditions for equalization and anaerobic treatment by controlling in-time any fermentation reaction occurring therein in order to produce an acidogenesis fermenting phase of organic materials and prevent the methanogenesis phase. Then, the fermented wastewater from the first SBR is rapidly transferred by batch into the second SBR. In the second SBR, the wastewater is first anaerobically treated to store a maximum amount of volatile fatty acids (VFAs) in the phosphorus removal biomass.

Abstract: A method for removing pollutants from water, according to the preferred embodiment of the present invention, comprises the steps of providing algal spores for seeding, providing a source of water for flowing through a floway, and the water contains a quantity of pollutants and has a pH on entry into said floway, providing a growing surface in the floway upon which the algal spores form an attachment, subjecting the algal spores in the floway to operating conditions resulting in the formation of an algal turf in which the algae has cell walls on its surface, adjusting the floway operating conditions such that a predetermined pollutant precipitates onto and/or into the algal cell walls but not into the water, and harvesting a portion of the algal turf including the cell walls onto and/or into which the pollutants have precipitated.

Abstract: A process and a system for the purification of waste water in several successive stages includes a first stage for anaerobic treatment of the waste water, a second stage for aerobic treatment of the waste water, a third stage for clarification and sedimentation of the waste water with a sludge return, and an arrangement for controlling the residence time of the waste water in the anaerobic stage by varying the volume of the anaerobic stage.

Abstract: A method for treating waste water which comprises passing the water through a series of steps including sequentially passing the water through an aeration step, and then a plurality of treatment cells wherein each treatment cell comprises a trickle filter cell. The waste water is subsequently subjected to a denitrification step and to a dephosphorization step. It is then passed through a trickle filter cell and optionally may be treated by passing through a cell wherein the waste water is in contact with peat moss.

Abstract: Described is a two-stage sewage treatment plant (10), in particular for domestic sewage, wherein the first biological purification stage (12) is dimensioned so that besides the carbon load, the mean nitrogen load is maximally degraded. Any peak loads that may appear are degraded in the second biological purification stage (13). This makes possible a space-saving construction and an economical operation. The second biological purification stage (13) is always a two-stage filtering installation with a filter stage (20) for nitrification and a filter stage (21) for denitrification. The first biological purification stage (12) can be an activated sludge stage as per A 131, a pure oxygen activated sludge or likewise a two-stage filtering installation.

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

Abstract: This invention refers to an original solution for the purification of contaminated water streams with the activated sludge method, involving: a) a two-stage aeration system operating at high rate and low rate conditions respectively, where the first stage operates in anoxic conditions promoting denitration, whereas the second stage operates under oxidant conditions so that nitrates are removed to an extent of 70%; b) a system for moving the biological sludge, where the sludge produced in the first aeration tank is totally rejected, and that produced in the second aeration tank is recycled to the first.

Abstract: A composition for treating water or flue gases that contains metal ions and possibly also organic and/or inorganic compounds is produced by reacting sulfur with an alkali- and/or alkaline earth metal hydroxide in the presence of water.The inventive composition corresponds to general formula IM.sub.x S.sub.y O.sub.z, (I)where M represents an alkali or alkaline earth metal,x is 1 or 2,y is in the range 0.5x-4.0x, andz is in the range 0.1-2.5.Alkali sulfite salts, particularly sodium salts, may also be added to the compound for reducing H.sub.2 S emission.

Abstract: An improved process for removing phosphate from waste water comprising simultaneously injecting a coagulating agent upstream and downstream of a stage of biological oxidation in aerobic medium.

Abstract: Control of a water/wastewater treatment system is effected by sensing the oxidation reduction potential (ORP) at various parts of the system and using neuro-adaptive process control techniques to make adjustments when necessary based on the ORP values. Internal nitrate recycling, sludge return, organic substrate addition and/or aeration can be adjusted to achieve the desired environmental conditions. In the event that phosphorus removal is necessary, the system can be used to assure proper detention time needed for biological phosphorus uptake.

Abstract: A method of processing waste water comprises atomizing waste water under selected atmospheric conditions to achieve substantially complete phase change of the water. The atomization is conducted by spraying waste water from a nozzle mounted on a tower adjacent a catchment area for collecting ice crystals produced by the phase change of the atomized waste water into ice crystals, under atmospheric conditions favourable to freezing of atomized water droplets into ice.

Abstract: A device for treating fluid, particularly polluted water such as add-sulphate water. The device includes a stainless steel chamber which is provided with buoyancy pontoons allowing it to float in communication with the polluted water in a reservoir. The chamber is provided at both ends with openings which allow water to flow freely into and out of the chamber for treatment. A trap door provides an entry for water treatment reagent and a motor and gearing system rotates the chamber about its axis. The rotation of the chamber combined with the action of the internal mixer flights serve to agitate the water and reagent mix with a milling action.

Abstract: A system and method of sewage treatment which comprises the sequential steps of:(i) subjecting waste water to be treated to a primary settling means to remove settleable solids and suspended solids and produce settled effluent;(ii) passing the settled effluent through a peat filter; and(iii) collecting the effluent from the peat filter and passing it through a sub-surface constructed wetland.

Abstract: The invention relates to methods and processes for the photoassisted oxidation of dissolved species such as arsenic, iron, phosphorous and sulphur. Each aspect of the invention involves supplying to a solution including the species to be oxidized, an oxidant and a photoabsorber, and then irradiating the resultant solution with UV/electromagnetic radiation. The resulting oxidised species can then be subsequently treated, used and/or removed (e.g. through precipation/co-precipitation).

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: A process for removing lead from drinking water discharged from a drinking water outlet comprising:(a) directing the water through a first matrix comprising a calcium mineral of between 10 and 100 weight percent of a solid calcium phosphate mineral which is slightly soluble in water, the remaining portion being a solid calcium carbonate mineral which is slightly soluble in water, such that there is sufficient contacting between the water and the first matrix to introduce sufficient phosphate ions into the water to form lead precipitate and reduce the lead concentration in the water to below 15 parts per billion,(b) directing the lead depleted water from step (a) through a second matrix, the second matrix comprising a mineral that when in equilibrium with the water reduces the phosphate ion concentration to 60 mg/L or below.

Abstract: A dephosphorizing material containing iron and/or an iron-containing compound, a cementitious material, water, and a mixing agent for accelerating bleeding as the starting material, and having fine pores therein formed by solidifying the starting materials while bleeding not less than 2.0% by weight of the water contained in the starting materials to render the percent water absorption of not less than 10%; and a dephosphorizing method which includes bringing the dephosphorizing material into contact with a phosphorus-containing aqueous solution. This dephosphorizing material can effectively reduce the phosphorus concentration in sewages, rivers, or the like by fixing the phosphorus component on its surface. The dephosphorizing method is so simple that it can be effected merely by bringing the dephosphorizing material into contact with a phosphorus-containing aqueous solution, thus being capable of removing the phosphorus component effectively without necessity for any special controls.

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

Abstract: A process for biologically removing nitrogen and other nutrients from wastewater using recycled activated sludge. A mixed liquor is formed from influent wastewater and recycled activated sludge and then treated in two successive nitrogen removal stages, each stage having an anoxic denitrification zone and an aerobic nitrification zone. The first nitrogen removal stage entails circulating the mixed liquor back and forth between the anoxic zone and the aerobic zone. The mixed liquor is then transferred to a final clarifier where activated sludge is separated from purified supernatant. To increase the NO.sub.x.sup.- reducing enzymatic activity of denitrification microorganisms, the activated sludge is retained in the final clarifier for a time period sufficient to permit adaptation of these microorganisms to a nitrate/nitrite-respiring metabolic pathway.

Abstract: An activated sludge treatment process and apparatus are provided for denitrification of a trickling filter plant effluent in which the nitrate nitrogen to BOD5 ratio can be maintained at less than or equal to 0.18 without the use of a nitrate monitor to control supplemental dosing with carbonaceous organic compounds or their salts. The apparatus is equipped with a turbidity meter, a phosphate monitor, and with a substrate storage tank for the addition of carbonaceous organic substrate. The substrate is added immediately at the end of the oxic phase and is continued until phosphate release is detected. Accordingly, the phosphate monitor functions as an indicator of nitrate respiration in the anoxic phase.

Abstract: A method for treating poultry litter which inhibits ammonia volatilization and reduces soluble phophorus levels in the litter. The method comprises the addition of alum to litter in an amount sufficient to maintain the litter pH at values low enough to inhibit ammonia volatilization. The addition of alum, iron or calcium compounds to litter also effectively precipitates soluble phosphorus in litter, thereby reducing the amount of soluble phosphorus runoff from fields receiving litter.

Abstract: A method for purifying aqueous solutions having varying concentrations of contaminants and/or various contaminants including ions of several metals and elements by conducting precipitation in a first precipitation stage by adding lime in a surplus quantity whereby a pH of about 12 is established and maintained in the solution and a major part of the contaminant content is precipitated so as to form a solution having a substantially constant composition and to form a precipitate that is isolated and removed together with residual lime. Precipitation is then conducted in a second precipitation stage by adding a reagent for precipitation at a pH in the range of 4-11 wherein residual contaminant in the formed solution from the first precipitation stage is precipitated the precipitate is isolated and returned to the first precipitation stage.

Abstract: A sewage purification method which includes a first step in which at least two kinds of flocculants are introduced in sewage for stirring and mixing therewith so as to float and settle inorganic and organic materials. The first step is sequentially repeated more than one time. Next, at least three kinds of flocculants are introduced into the supernatant obtained in the first step for stirring and mixing therewith so as to further float and settle remaining inorganic and organic materials. At least one of the first and second steps is sequentially repeated more than one time. In the above way, middle water, drinking water and super-pure water can be obtained from sewage. Purification of exhaust gas is also possible by introducing such exhaust gas in one of the above steps.

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

Abstract: The method is of the type wherein the raw or untreated water to be treated is made to circulate in cells or biofilters with submerged filtering beds working anaerobically and then aerobically or vice versa. A treatment module is used comprising at least two cells or biofilters in series (for example one biofilter under anaerobic conditions and one to five biofilters under aerobic conditions) in making phases of anaerobiosis and then aerobiosis alternate cyclically. The entry of flow to be treated takes place always in the anaerobic cell. Advantageously, each phase of the cycle is separated from another by a hold phase comprising a halt in the supply of water to be treated.

Abstract: This invention is directed to an activated sludge treatment process for removing phosphorus and nitrogen from wastewater. The process includes providing wastewater influent and activated sludge in a stressed contact zone to form a mixed liquor. In a luxury contact zone, the mixed liquor is mixed and aerated and the organisms in the activated sludge take up at least portion of the phosphorus. The method further includes separating the activated sludge from the mixed liquor, and returning at least a portion of the activated sludge to the stressed contact zone. The inventive process accomplishes wastewater treatment without having to pass the wastewater through an anaerobic zone.

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

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

Abstract: A process for reducing the phosphate content in waste water from the preparation of salts of ascorbic acid 2-monophosphate comprisesA. treating the waste water from the crystallization of the metal salts of ascorbic acid 2-monophosphate with an alkali metal or alkaline earth metal hypochlorite, chlorine or H.sub.2 O.sub.2,andB. precipitating, at a pH of 9-12, the inorganic phosphate which has been produced from organically bound phosphorus and/or was present in the waste water, especially as calcium phosphate.

Abstract: A process and apparatus are described for clarifying milkhouse wastewater, which is rich in phosphorus and also contains colloidal and suspended solids. This wastewater is obtained during the washing of milk pipelines of a dairy milking system. The wastewater is collected in a treatment vessel, with the ratio of suspended solids to phosphorus in the wastewater being lowered either before entering or while in the treatment vessel. To this wastewater of lowered suspended solids:phosphorus ratio, there is added sufficient calcium, preferably in the form of lime, to react with all of the phosphorus in the wastewater to form calcium hydroxyapatite precipitate. It has been discovered that, by lowering the ratio of suspended solids:phosphorus, sufficient calcium hydroxyapatite precipitate is formed to sweep with it during settling substantially all colloidal and suspended solids thereby leaving a clear, environmentally safe effluent water.

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

Abstract: Generation of Fe.sup.+2 for water treatment and treatment process using a microbe capable of converting Fe.sup.+3 to Fe.sup.+2 wherein the microbe is selected from ATCC 55339.

Abstract: A method for waste water (1) treatment comprising the steps of: (a) combining waste water (1) with activated sludge (4) under anaerobic conditions; (b) transferring the products of step (a) to a container (B); (c) aerating the contents of the container (B); (d) allowing the contents of the container to settle and separate into an effluent layer (3) and an activated sludge layer; (e) decanting at least some of the treated effluent (3) and (f) recycling at least a proportion of the activated sludge (4) from step (d) to provide the sludge of step (a).

Abstract: Waste water is disposed in a flocculation mixing tank 1, an anaerobic tank 2 and an aerobic tank 3 connected in series. First, a dephosphorization flocculating agent and, if necessary, a polymeric flocculating agent are added to waste water in order to produce and grow phosphorus-containing flocs therein. Then, to the water is added a recycling solution from an aerobic tank 3, said solution containing nitrates and nitrites. The mixture water is charged in an anaerobic tank 2 until microbially decomposable components (herein referred to BOD components), nitrates and nitrites are anaerobically and microbially decomposed and gas is produced. In the aerobic tank 3 is charged a supernatant solution from the anaerobic tank 2, said solution containing ammonium compound and BOD components, to nitrates, nitrites and CO.sub.2. At least a part of supernatant solution containing the nitrates and nitrites is recycled to the anaerobic tank 2. Solids discharged from the anaerobic tank 2 and the aerobic tank 3 are wasted.

Abstract: The present invention provides a method for purifying agricultural waste. The method includes the steps of adding effective amounts of at least one polymer flocculent, at least one coagulant, and at least one precipitant. The combined effect of the various components of the present invention not only purifies the agricultural waste but also yields a dewatered organic mass for composting to act as a peat replacement.

Abstract: Metals have phosphates of low water solubility e.g. Cd, Pb, Cu, Mn, Sr, U, La, Pu, Am and Np, are removed from water by reaction with phosphate produced by enzymatically-cleaved polyphosphate which has been accumulated by one or more polyphosphate-accumulating microorganisms.

Abstract: A dephosphorizing material disposed so that a material containing iron as a main component and a calcium compound material contact a phosphorus-containing aqueous solution, and provided with a water-permeable material at least around the material containing iron as a main component. A phosphorus component of sewage and river water can be removed easily by simply bringing this dephosphorizing material into contact with such phosphorus-containing aqueous solutions, without employing any special solution control method. This dephosphorizing material is capable of reducing the outflow of iron rust occurring due to the oxidation of iron during a dephosphorization of a phosphorus-containing aqueous solution, and the iron effluent can be eliminated by the action of the calcium compound material. Accordingly, this dephosphorizing material can be applied practically to sewage and river water.

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

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

Abstract: The specification discloses a process and apparatus for the purification of wastewater in several successive stages wherein the wastewater is aerated in a first region and is then subjected to intermediate clarification in a second region and including a post-clarification aeration in a third region and post-clarification sedimentation in a fourth region.In order to provide a simple, space-saving, low-cost yet reliable wastewater treatment arrangement, the apparatus is arranged to include all four regions in one basin by providing separating walls in the basin. These regions can be preceded by other processing stage regions and followed by filtering or storage regions.In order to allow adjustment for varying loads and for changing relationships between hydraulic and biochemical loads, the separating walls between the regions are arranged to be movable to permit changes in the relative volumes of the regions.

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.

Abstract: A composition for treating water that contains metal ions and possibly also organic and/or inorganic compounds is produced by reacting sulfur with an alkali- and/or alkaline earth metal hydroxide in the presence of water.The inventive composition corresponds to general formula IM.sub.x S.sub.y O.sub.z, (I)whereM represents an alkali or alkaline earth metal,x is 1 or 2,y is in the range 1.5x-2.5x, andz is in the range 0.1-2.5.

Abstract: Disclosed is a process for removing by-product phosphorus-containing (PO.sub.x) materials, alendronate and alendronate byproducts from crude mother liquors in an omega amino-1-hydroxy-C.sub.2 -C.sub.6 alkylidene-1,1-bisphosphonic acid synthesis process, e.g. alendronate sodium. Calcium chloride is added first to the crude mother liquors, then calcium oxide to precipitate the PO.sub.x materials, then neutralized to about pH 7 to complete precipitation. Substantially all of the alendronate sodium active ingredient is removed from the precipitate. Following filtration, the PO.sub.x filtercake can then be disposed of by incineration, landfilling or reclamation of usable phosphorus as fertilizer. The remaining filtrate can then be further treated in an environmentally acceptable manner by wastewater treatment or recycling to the process.