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: Apparatus and method for the simultaneous purification of air and water, using a plurality of compartments arranged in a series extending from a first to a last compartment. Each compartment is partially filled with a biologically active material. Air and water to be purified are introduced into the first compartment into a lower portion thereof. Each said compartment other than the last compartment has outlets for air and water adjacent an upper portion thereof communicating with conduits for conveying air and water to a lower portion of the next compartment in the series. Each compartment other than the last has a closed top such that air can leave only through the conduits and pass to a lower portion of the next compartment. The last compartment has outlets adjacent an upper portion thereof for purified air and water.