Abstract: A modified activated sludge system is provided wherein wastewater is treated to reduce BOD, nitrogen, and/or phosphorus. The disclosed system features a zone sequence nitrification/denitrification, with nitrification induced by recycling mixed liquor that contains a significant concentration of oxygen and nitrifying bacteria. With a further modification, the main treatment zones of the treatment system are split into two or more parallel treatment trains that are either high-loaded with BOD or low-loaded with BOD. The high-loaded sections facilitate the sludge generation and BOD removal, while the low-loaded sections are operated for nitrification and to enhance the growth of nitrifying bacteria. The parallel treatment zones combine and pass into a final denitrification zone. Phosphorus removal is achieved with phosphate release in a reverse flow regime to the main treatment, and phosphate retention primarily in aerated treatment zones in the main stream of the process.

Abstract: The invention relates to a method for the treatment of (raw) sewage in a package plant consisting of three bioreactors in series. The treatment is being carried out using three types of biomass.In a first step phosphate is removed by biological means and, at the same time, the chemical and biological oxygen demand is lowered in a highly loaded active sludge system, in a second step a nitrification is carried out, ammonium being converted to nitrate, and in a third step a denitrification is carried out using a carbon source. In the denitrification step acidified surplus sludge from the P-removing step can also be used instead of an external carbon source. The nitrifying and denitrifying bioreactors are both fixed film processes. The thickness of the biofilm on the support material in the nitrifying bioreactor can be influenced by adjusting the aeration system or by adjusting the hydraulic loading.

Abstract: A process is disclosed for treating wastewater from a polymerization process. The wastewater contains volatile residual monomer, for example acrylonitrile monomer. The method includes the steps of pretreating the wastewater with an amount of oxygenated waste activated sludge to reduce the levels of residual monomer in the wastewater stream in order to reduce the volatilization of the volatile residual monomer into the atmosphere during further treatment of the wastewater stream. Preferably the process involves steps of neutralization, primary clarification, cooling, aeration and secondary clarification to provide a wastewater treatment process that has a minimum of air emissions of residual volatile hydrocarbon monomer and which provides a final treated water effluent that has the desired pH level, temperature, biological oxygen demand and a suspended solids level for emission of the treated water into the environment.

Abstract: The invention relates to a method for processing manure, liquid manure and/or Kjeldahl-N containing waste water being subjected to a nitrification in an aerated reactor containing active sludge and to a denitrification in a high rate recirculation denitrification reactor (13) containing a very compact biomass capable of converting nitrate to nitrogen gas. The loading of the nitrification reactor (9) being controlled to obtain an optimal nitrification and denitrification, the effluent from the nitrification reactor (9) partially being passed to the denitrification reactor (13), adding a source of carbon to the effluent to be passed to the recirculation denitrification reactor (13) and passing another portion of the effluent stream from the nitrification reactor (9) to a separation step (19) to separate a sludge, the effluent from separation step (19) being passed to a discharge line denitrification reactor (37) under the addition of a carbon source if desired.

Abstract: A continuous process by which waste water containing low to high concentrations of organic constituents and total nitrogen is biologically purified to such an extent that the organic constituents are minimized, the content of total nitrogen is completely nitrified, if it exceeds the assimilation demand, and the nitrate formed is reduced by aerating the waste water or exposing it to oxygen while not exceeding a preselected redox potential. In the subject process, the expenditure on the oxygen introduction and the expenditure on the denitrification are minimized. Further, the amount of excess sludge produced is extremely small.

Abstract: A high rate multi-stage bubble separation process is developed for: (a) initially generating coarse gas bubbles with diameters greater than 80 microns in turbulent hydraulic condition to mix an influent water with chemicals, enzymes, microorganisms, or combinations thereof, to produce chemical flocs, biological flocs or both, and to strip volatile contaminants from water; (b) subsequently terminating coarse gas bubbles and generating extremely fine gas bubbles with diameters smaller than 80 microns in laminar hydraulic condition to float suspended, oily and surface-active contaminants together with said chemical flocs and said biological flocs from water, to settle heavy contaminants from water, and to produce a clarified effluent water, a floating scum, and a sludge; (c) terminating the fine gas bubbles and discharging the clarified effluent water; (d) discharging the floating scum and the sludge upon demand; and (e) optionally collecting and treating an emitted gas stream resulting from said coarse gas bubb

Abstract: A modified activated sludge system is provided wherein wastewater is treated to reduce BOD, nitrogen, and/or phosphorus. The disclosed system features a zone sequence nitrification/denitrification, with nitrification induced by recycling mixed liquor that contains a significant concentration of oxygen and nitrifying bacteria. With a further modification, the main treatment zones of the treatment system are split into two or more parallel treatment trains that are either high-loaded with BOD or low-loaded with BOD. The high-loaded sections facilitate the sludge generation and BOD removal, while the low-loaded sections are operated for nitrification and to enhance the growth of nitrifying bacteria. The parallel treatment zones combine and pass into a final denitrification zone. Phosphorus removal is achieved with phosphate release in a reverse flow regime to the main treatment, and phosphate retention primarily in aerated treatment zones in the main stream of the process.

Abstract: A biological treatment system involving the use of a gas dissolving pressure vessel, a pressurized water release assembly, a pretreatment chamber, a bioreactor, an open vessel, a post-treatment unit, a sludge removal unit, and a removable gas collection and purification unit for both wastewater treatment and air emission control is described. Gases are dissolved efficiently in a water inside the pressure vessel under controlled high pressure and high rotating velocity. Chemicals, or microorganisms, or both arm dosed to an influent water producing a pretreated water containing chemical flocs and biological flocs. The bioreactor comprising a hanging biological contactor is adopted when biochemical reaction is intended. A pressurized water containing supersaturated gases is produced in the pressure vessel and than depressurized through the pressurized water release assembly becoming a depressurized water containing micro bubbles.

Abstract: Conventional biological processes for treating wastewater include the so-called activated sludge process which is continuous and the sequencing batch reactor (SBR) activated sludge process. The first process requires the use of dedicated, relatively expensive external clarifiers, and the second process is inefficient in terms of treatment volume. A modified sequencing batch reactor process and system enable the efficient, continuous treatment of wastewater, combining the advantages of the SBR and activated sludge processes. Wastewater is treated in three contiguous treatment sections, each of which includes a plurality of contiguous cells. In a first series of operations, the flow direction is from the first to the third sections, and in a second series of operations the flow is reversed. In each series of operations, the first step is to aerobically treat the wastewater, and then allow the sludge to settle before discharging the treated wastewater from the system.

Abstract: A process is described for the operation of a multiple zone batch treatment system for biological or biophysical treatment of wastewater. The system comprises two or more batch treatment zones with wastewater passing sequentially through all treatment zones. After the mix and settle batch steps occur for all zones, influent wastewater flows into the first zone and displaces clarified wastewater in a plug flow mode through each treatment zone and ultimately from the last zone. The combining of the decant and fill steps for all or most of the zones provides for shorter cycle times and greater capacity for the system.

Abstract: In treating effluent from an integrated paper mill having bleach plant effluent (including kraft mill effluent) and paper mill effluent (including effluent from a mechanical pulp mill) it has been found that if the two effluents are separately biologically treated and the recycled activated sludge directed to treatment of the bleach plant kraft mill effluent contains a significant portion of activated sludge derived from the treatment of the paper mill effluent that a significantly higher percentage of the absorbable organic halogens (AOX) can be removed from the bleach plant effluent.

Abstract: The invention relates to an apparatus and process useful for the biological transformation of waste materials into ecologically desirable materials. A meta system reactor is disclosed comprising three primary zones which are cyclically and dynamically connected by a circulating fluid. In the process of the invention, each of a bioreactor zone, solids ecoreactor zone and georeactor zone further comprise secondary subsystems and are cyclically connected by a series of recycle flows and organism movements to bioconvert the contained materials. The converted materials produced can be desirable and ecologically beneficial end products comprising gases such as nitrogen, oxygen, carbon dioxide, and water vapor; a biologically active and highly beneficial humus material; and clean water which may be passed through a final wetlands polishing and biomonitoring system before discharge into a natural receiving water.

Abstract: A process for high-load treatment of carbohydrate-containing waste water comprises the steps of separating a yeast appearing in the waste water, subjecting the separated yeast to large-quantity culture, and treating the waste water by a high-load operation using the cultured yeast as a seed fungus under the conditions of a volume load of 10 to 80 kg-BOD/m.sup.3 .multidot.day and a yeast load of 1.0 to 5.0 kg-BOD/kg-yeast.multidot.day, whereby it is possible to treat the high-concentration waste water efficiently with a small volume for treatment. To obviate the conflict between the yeast and bacteria, it is recommendable to add Cl.sub.2 to a reservoir in an amount of 10 to 50 mg/l. Upon the treatment of the waste water, a surplus of yeast is generated, which contains proteins and vitamins in high contents and, therefore, is capable of being taken by a fodder company as fodder or fertilizer; thus, the disposal cost associated with the surplus yeast is saved.

Abstract: The invention relates to a method for processing manure, comprising the steps of:i) adding an organic carrier liquid to the manure;ii) concentrating the mixture of manure and carrier liquid;iii) condensing the formed vapor;vi) anaerobic treating of the condensate; andv) aerobic treating of the effluent from the anaerobic treatment.Preferably the effluent deriving from the anaerobic treatment is denitrified in a denitrification unit and nitrified in a nitrification unit, and wherein a portion of the sludge-influent mixture from the nitrification unit is recirculated to the denitrification unit.The treating yield is greater than 90%, preferably greater than 95%, such as 97-99% BOD.

Abstract: The present invention entails a process for treating wastewater utilizing a return activated sludge process. Primary sludge is separated from the wastewater stream and conveyed into a fermentation tank and held a sufficient time to permit hydrolysis of suspended solids so as to produce soluble substrates. Part of the soluble substrates are mixed with nutrified return activated sludge and held for a selected time period to form conditioned return activated sludge. Thereafter, the conditioned return activated sludge is mixed in an initial aerobic treatment zone with pretreated wastewater. Thereafter, the mixed conditioned return activated sludge and pretreatd wastewater is conveyed through a series of treatment zones, which includes at least one anoxic treatment zone, to which part of the soluble substrates are added, where nitrogen and other pollutants are removed from the wastewater.

Abstract: A sewage treatment plant for the purification of waste water includes a chamber container (1) divided by partitions (4) into different sections (6, 7, 8) for pretreatment, biological treatment, chemical treatment, intermediate or retreatment of waste water, each section (6, 7, 8) having several chambers (6a through f, 7a through f, 8a through f) separated from one another by dividing walls (4, 5), chambers (6a through f, 7a through f, 8a through f) being linkable, with regard to inflow technique, in any pre-selectable association depending on the quantity and type of waste water to be treated, and at least one installation for removal of deposited treatment sludge in each of the areas for pretreatment, intermediate treatment and retreatment.

Abstract: The present invention entails a process for treating wastewater utilizing a return activated sludge process. Primary sludge is separated from the wastewater stream and conveyed into a fermentation tank and held a sufficient time to permit hydrolysis of suspended solids so as to produce soluble substrates. The soluble substrates are mixed with the return activated sludge and held for a selected time period in an anoxic zone, to form conditioned, denitrified return activated sludge, followed by anaerobic treatment, to produce microorganisms that are capable of biologically removing phosphorus. Thereafter, the conditioned return activated sludge is mixed in an initial aerobic treatment zone with pretreated wastewater. Thereafter, the mixed conditioned return activated sludge and pretreated wastewater may be conveyed through a series of treatment zones, which may include at least one anoxic treatment zone.

Abstract: A process for treating wastewater to biologically remove phosphorous as well as lowering ammonia, TSS and BOD levels is provided. The process employs a plurality of basins which may be individually controlled to achieve anaerobic, anoxic or aerobic conditions. The basins are reconfigurable in that the flow of influent to a basin, transfer of mixed liquor between basins and effluent discharge from a basin can be varied to create a treatment cycle which has features of both continuous and batch processes while minimizing recycle rates and hydraulic level changes.

Abstract: The invention relates to an installation for aerobic biological purification of pollutant-containing water, which installation consists of an axial-flow submerged reactor and a sedimentation tank for separation of the biosludge from the purified water. The reactor is a pipe containing a two-stage activated-sludge chamber, which pipe contains (a) a first activated-sludge stage in which a driving-jet nozzle is disposed at the downstream end for the dispersion of the air and the microorganisms in the waste water to be purified, and (b) a second activated-sludge stage in which internals are disposed for homogeneous dispersion of the gas bubbles and the microorganisms as well as for immobilization thereof.

Abstract: A two-stage process for purifying wastewater includes the steps of biophysical anaerobic treatment to remove the majority of the COD, followed by biophysical aerobic treatment to further purify the wastewater. A powdered adsorbent, preferably powdered activated carbon, is used with biological solids in each treatment step. Excess biophysical solids from the aerobic step are transferred to the anaerobic step for digestion. Fresh powdered adsorbent is added to the aerobic treatment step to compensate for that transferred to the anaerobic treatment step. Solids concentration in the anaerobic step is controlled by wasting solids to disposal.

Abstract: Water contaminated with at least one volatile compound is treated by air stripping the volatile compound into the gas phase, then removing the volatile compound from the gas phase by contacting it with an aqueous mixture of biological solids and powdered adsorbent. The partially-purified water is further treated by a biophysical aerobic process which in turn produces the aqueous mixture of biological solids and powdered adsorbent used to remove the volatile compound from the gas phase. The aqueous mixture of biological solids and powdered adsorbent containing the volatile compound is thickened and the solids slurry treated by regeneration, preferrably wet air oxidation, to destroy the biological solids and volatile compound as well as regenerate the powdered adsorbent. The regenrated adsorbent may be returned to the biophysical aerobic treatment process.

Abstract: A process for purifying waste water resulting from the manufacture of chemo- and/or thermomechanical pulp, which comprises subjecting the waste water to at least the following sequence of steps:sedimentation of coarser constituents (4);cooling (6);detoxification (7);anaerobic hydrolysis and preacidification (10) with addition of nutrient salts and readjustment of the redox potential;production of methane in a methane reactor (11);aerobic purification and separation of biologic sludge (12; 13), which is at least partly recycled to the detoxification step (7), in which process aerobic sludge is separated prior to the anaerobic hydrolysis step (10).

Abstract: A method for the treatment of activated slurries of waste water, notably of urban waste water, characterized in that the water to be treated, previously subjected to the standard prior treatments such as screening, renewal of sediments, degreasing, and possibly a primary decantation, is directed to a single ventilation or aeration basin with a high mass load where it dwells during a reduced period, from which it is discharged to a clarifier-thickener equipped with inclined parallel plates or tubes, stimulating the separation of the slurry, which is being recycled in the ventilation or aeration basin at a high concentration made necessary by the reduced dwelling time of the water in the basin.

Abstract: A process is provided for the removal of heavy metals from wastewater prior to being fed to a wastewater treatment installation, with anaerobic sludge to cause the anaerobic sludge to absorb heavy metals in the wastewater. Thus, the heavy metals depleted wastewaters can then be treated in a conventional treatment plant and thereafter, the resultant sludge can be directly employed for agricultural purposes without requiring further treatment to remove heavy metals therein. To effect the process a preferred reactor is made up of two parts, a cylindrical mixing tank and a superposed funnel-shaped sedimentation zone.

Abstract: A wastewater treatment reaction vessel is operated with repeated sequences of aeration and non-aeration, using a single vessel or multiple vessels alternately, activated sludge which is acclimated for BOD reduction, nitrification or biological denitrification and phosphorus removal is absorptively reacted with influent wastewater, and the combined flow is passed into subsequent absorptive reactor volumes, reducing the BOD such that the effluent BOD is less than twenty percent that of the influent.

Abstract: A method of biological purification of waste water by removing organic contaminants therefrom by activated sludge in two purification stages is proposed. The primary stage involves mixing waste water with activated sludge, aerating the mixture and separating recyclable sludge and sludge water. The recyclable sludge is regenerated and fed for mixing with waste water. At the secondary stage the sludge water of the primary purification stage is aerated and residual activated sludge is removed therefrom. The recyclable sludge delivered for regeneration is divided into two flows one of which is fed directly for regeneration, whereas the other is compacted prior to regeneration to be mixed with the first for joint regeneration. An invariable ratio between the amount of organic contaminants carried by incoming waste water and activated sludge is continuously maintained at the first purification stage. An aeration tank for carrying out the proposed method comprises mixing vessels of the primary and secondary stages.

Abstract: Wastewater is passed sequentially through an anaerobic treating zone and an oxic treating zone, followed by separation from the treated liquor of a dense sludge containing activated biomass, a least part of which is recycled to provide the activated biomass employed in treating the influent wastewater. Of the part of the sludge so recycled a minor portion is introduced into the anaerobic treating zone for admixture with the wastewater influent and the remaining major portion is introduced into the oxic treating zone, into which oxic zone oxygen-containing gas is admitted to effect oxygenation of the contents of that zone.

Abstract: A waste water stream is clarified by phase separation of a part of the stream in a clarifier positioned in an oxidation ditch, through the establishment of a head differential between the level of liquid in the clarifier and the level of liquid in the oxidation ditch.

Abstract: Phosphorus, nitrogen and BOD are removed from organic waste liquid containing the same by mixing the organic waste liquid with activated sludge which is substantially free of oxygen, nitric acid and nitrous acid and subjecting the mixture to the action of the activated sludge under anaerobic conditions which forms a mixture of a liquid rich in soluble phosphorus and an activated sludge low in phosphorus. The sludge and liquid are separated. A portion of the liquid is subjected to solid-liquid separation to form a liquid high in phosphorus and a sludge low in phosphorus. This latter sludge is, along with the other portion of the liquid and the sludge from which the liquid has been initially separated are mixed with oxygen, in the presence of nitric acid or nitrous acid and subjected to aerobic biological oxidation. This results in the formation of a liquid low in phosphorus and an activated sludge.

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

Abstract: Disclosed is a process for treating waste water through the use of activated carbon. The carbon is generally added to waste water having a pH from about 4 to about 11, and is commonly added after the waste water has undergone primary treatment. Preferred modes of operation comprise using low concentrations of activated carbon having a high surface area and a zeta potential greater than about -10 millivolts. It is also preferred to use activated carbon in conjunction with an activated sludge process having an average sludge age greater than about ten days, especially where the waste water undergoes a pretreatment prior to the activated sludge process to reduce chemical oxygen demand, oil and solids content. Low concentrations of activated carbon based on feed waste water are generally used while maintaining substantially higher carbon concentrations in the process.

Abstract: A process and apparatus for the treatment of aqueous waste materials or effluents, particularly the aqueous waste materials of bottling plants and installations, in which a trickling element is employed for the basic rough processing to effect the removal of biological oxygen demand (BOD). The discharge stream of effluent from the trickling element is conveyed into an oxidation-reaction tank, providing for the chemical oxidation of light organic floc resulting from biological action in the trickling element and further BOD reduction, and for the oxidation of any biomass sloughing off the media in the trickling element. The treated waste material or effluent discharge emanating from the oxidation-reaction tank is conducted through a mixing tank which is adapted to simultaneously receive the final rinse waste effluent from the bottling plant, and to intermix the two effluents and subject these to further oxidation treatment through the intermediary of admixing air therewith.