Abstract: A method of biologically treating wastewater with an integrated fixed film activated sludge process. The integrated fixed film activated sludge process includes biomass suspended in mixed liquor and biomass disposed on carriers. Under certain conditions the dissolved oxygen concentration in a reactor that includes the mixed liquor, biomass suspended in the mixed liquor, and the biomass on the carriers, biological treatment is performed primarily by the biomass in the mixed liquor. This is achieved by controlling or maintaining the dissolved oxygen concentration in the reactor at a relatively low concentration. When the biomass suspended in the mixed liquor is unable to adequately biologically treat the mixed liquor, the dissolved oxygen concentration in the reactor is controlled or maintained at a relatively high concentration. This enables biomass on the carriers to contribute more to the biological treatment of the mixed liquor than when the dissolved oxygen concentration was maintained relatively low.

Abstract: A method for removal of ammonia from a polluted medium avoids the disadvantages related to the chemical-physical properties of an ammonium-containing salt (MAP). The method has improved technical and economical operational parameters and produces a reusable and environmentally friendly nitrogen fertilizer. All chemical processes and mechanical steps of the method are carried out in one single container, with the different steps divided into time phases. The chemical products are prevented from transportation between compartments and contact with pumps and pipes. Only liquids without precipitates are in contact with these elements. The method is applicable to ammonia-containing water from leachate, wastewater, the food industry, and agriculture.

Abstract: A method of biologically treating wastewater with an integrated fixed film activated sludge process. The integrated fixed film activated sludge process includes biomass suspended in mixed liquor and biomass disposed on carriers. Under certain conditions the dissolved oxygen concentration in a reactor that includes the mixed liquor, biomass suspended in the mixed liquor, and the biomass on the carriers, biological treatment is performed primarily by the biomass in the mixed liquor. This is achieved by controlling or maintaining the dissolved oxygen concentration in the reactor at a relatively low concentration. When the biomass suspended in the mixed liquor is unable to adequately biologically treat the mixed liquor, the dissolved oxygen concentration in the reactor is controlled or maintained at a relatively high concentration. This enables biomass on the carriers to contribute more to the biological treatment of the mixed liquor than when the dissolved oxygen concentration was maintained relatively low.

Abstract: The invention concerns a method and an apparatus for removal of ammonium from a polluted media, which avoid the disadvantages related to the chemical-physical properties of MAP, with the aim to improve the technical and economical operational parameters and to produce a reusable and environmental friendly produced nitrogen fertiliser. The invention concerns a method and a apparatus where all chemical processes and mechanical steps are carried out in one single container with the different steps split in time phases, whereby the chemical products are prevented from transportation between compartments and contact with pumps and pipes. Only liquids without precipitates are in contact with these elements. The apparatus includes a process container, an elevator unit and a flexible membrane which together enables all chemical processes, separation, mixing and gas extraction to be carried out in the same compartment.

Abstract: A process and a plant for the purification of waste water wherein the waste water is alternatingly treated in the two treatment zones under anoxic and aerobic conditions and the waste water thus treated is subjected to an aerobic treatment in a separate zone before it is introduced into a clarification zone from which purified waste water and sludge is removed, at least a part of the sludge being recycled to the waste water which is introduced into one of the two treatment zones.