A process for the purification of water is described, wherein a solution containing a proportion of a mixed microbiotic culture is added to the water in an environment having catalytic activity. This process may effectively be used for the purification of effluents and of waters in public and private installations.

The invention relates to a process for treating industrial wastewaters, preferably wastewaters from the metal-processing industry, preferably suitable for treating the wastewater in such a manner that it can be recycled back to the production. In the process the wastewater passes through a sequence of treatment steps consisting of a chemical/physical flocculation/precipitation, a filter system, a biological wastewater purification stage and also a nanofiltration unit.

A sewage treatment plant and method employing rapid sludge chemical dewatering technology in conjunction with slower conventional mechanical dewatering solids agglomeration and disposal methods to meet environmental permitting restrictions and siting limitations for disposal of sewage and wastewater.

A chemical/biological wastewater treatment plant apparatus and treatment method employing rapid sludge chemical dewatering technology in conjunction with an environmental biological system for treating the separated treated wastewater by land applying it for the propagation of biosynthetic fuels and other plants; and/or passing it through aqueous plant or microbial reduction of the dissolved solids and ammonia for BOD compliance to produce water of sufficient quality to reduce the overall salt l...

A method of cleaning a membrane in a membrane separation activated-sludge process. By the method, deposits adherent to the surface of a membrane used in a membrane separation activated-sludge process can be effectively scratched off and the membrane filtration rate can be prevented from decreasing. Membrane-cleaning particles (4) in which the surface to be in contact with the water to be treated has been hydrophilized and has a surface roughness of 100-2,500 .mu.m are introduced into a bioreacto...

A single-stage continuous aeration-batch clarification process for purifying wastewater containing pollutants includes the steps of continuously aerating the wastewater in the presence of biologically active solids and powdered absorbent in an aeration zone. A portion of the mixture of wastewater, biologically active solids and powdered absorbent is transferred to a settling zone where a settled solids phase and a clarified liquid phase are formed. During the settling step additional wastewater ...

This invention provides a method of reducing the concentration of at least one electrically charged compound present in aqueous feedstock (5), such as water and waste water. The feedstock to be treated is continuously supplied to one surface of a selectively permeable, electrically charged membrane (2) contained within a module (1). Simultaneously an aqueous reaction medium, containing an active microbial culture, contacts with the opposite face of the membrane (2). The microbial culture, fed wi...

Selenium compounds present in aqueous liquids containing sulfate and or chloride anions can be effectively removed by passing the liquid through a thiouronium modified anion ion exchange resin.

Industrial wastewater is contacted with a weak acid cation exchange resin, in the hydrogen ion form, to substantially reduce the sodium and ammonium alkalinity levels rendering the wastewater suitable, for example, as an environmentally acceptable cooling medium.

A method for recovering phosphate from sludge includes the processes of treating sludge drawn from a water treatment system at a sewage treatment plant in an anaerobic condition to release polyphosphate accumulated in the sludge into solution, and recovering phosphate in the solution using a seed crystal material. A system for recovering phosphate from sludge includes a phosphorus-releasing means for treating sludge drawn from a water treatment system at a sewage treatment plant in an anaerobic ...