Abstract: A polyurethane foam web with a thickness of 5 mm to 30 mm is passed continuously through a dipping bath and is thereby impregnated with 10% to 1000% by weight of a polymer dispersion consisting of the components A) and B) defined below:A) 30% to 65% by weight, preferably 40% to 60% by weight and particularly preferably 45% to 50% by weight of a cationic styrene/butadiene copolymer latex containing about 50% of dry substance, or of an anionic butadiene/acrylonitrile copolymer latex, andB) 10% to 50% by weight, preferably 15% to 40% by weight and particularly preferably 25% to 35% by weight of an inorganic and/or organic pulverulent filler,and the foam web treated in this way is compressed to remove excess liquid and then dried in a drying oven at temperatures of 80.degree. C. to 120.degree. C.

Abstract: In this process, a polyurethane foam web with a thickness of 5 mm to 30 mm is passed continuously through a dipping bath and is thereby impregnated with 10% to 1000% by weight of a polymer dispersion consisting of the components A) and B) defined below:A) 30% to 65% by weight, preferably 40% to 60% by weight and particularly preferably 45% to 50% by weight of a cationic styrene/butadiene copolymer latex containing about 50% of dry substance, or of an anionic butadiene/acrylonitrile copolymer latex, andB) 10% to 50% by weight, preferably 15% to 40% by weight and particularly preferably 25% to 35% by weight of an inorganic and/or organic pulverulent filler,and the foam web treated in this way is compressed to remove excess liquid and then dried in a drying oven at temperatures of 80.degree. C. to 120.degree. C.

Abstract: The fluid-bed reactor for biological effluent treatment, using carrier particles for microorganisms, consists of a tank with a retention system for the carrier particles, gas supply units and a jet ejector arranged along the tank for the particle recycle. The propulsion nozzle of the jet ejector is fed with the effluent stream which is to be treated.

Abstract: An apparatus for cultivating immobilized micro-organisms consisting of a fluidized bed reactor with fittings for gassing and a retainer system for the immobilized biocatalysts. The fluidized bed reactor is characterized in that the fittings for gassing consist of several segments with gas outlets arranged on the base of the fluidized bed reactor, which admit gas alternately or cyclically. A central gas outflow opening, pointing upwards, can be provided in the fluidized bed reactor as a further gassing unit. The method of operating the fluidized bed is characterized in that circulating gassing occurs in the reactor by means of sequential opening of the gas inflow openings of the segment-shaped fittings. In addition, switches may occur from the central gassing unit to gassing by means of the segment-shaped fittings or vice-versa.

Abstract: The fluidized bed reactor for biological treatment of effluent essentially comprises a container (1) over the base 2 of which elongated gassing units having gas exit apertures (5) are arranged parallel to one another, in such a way that in each case two neighboring circulating currents (8, 9) in mirror-image symmetry are produced in the reactor. In addition, the reactor (1) is supplied with a retention system (16) arranged on the outside for the separation of carrier particles for biocatalysts suspended in the effluent.

Abstract: In a two-stage process for the biological degradation of complex, non-readily degradable wastewater constituents, acidification takes place in the first stage and anaerobic degradation in the presence of methanogenic organisms in the second stage. In the first stage, the wastewater is treated both with the acidogenic organisms and with dehalogenating and/or desulfonating and/or deaminating strains. In addition, highly sub-stoichiometric quantities of oxygen, based on the organic carbon load, are introduced in the first stage either directly or indirectly by addition of oxygen-yielding compounds. Both stages are advantageously operated as fluidized-bed processes using supports to immobilize the biomass.

Abstract: Waste water and/or outgoing air are purified by contact with a polyurethane hydrogel containing surface active coal, a polymer having cationic groups and cells having enzymatic activity and being capable of growth.

Abstract: A biologically active composition is prepared comprising a polyurethane hydrogel containing surface active coal, a polymer having cationic groups and cells having enzymatic activity and being capable of growth. The composition is used for purifying waste water and outgoing air.