ANAEROBIC WASTE WATER TREATMENT

Abstract

Anaerobic digestion has been broadly recognized as the core of sustainable waste management. The anaerobic sludge reactor is the most widely and successfully used high rale anaerobic system for sewage treatment. It has gained a lot of popularity in tropical countries where sewage temperature is rather high, viz. 24- 27 °C. The anaerobic sewage treatment is certainly not limited to regions of hot climates. Two-stage systems consisting of a high loaded first stage followed by a methanogenic stage have been proposed for sewage treatment at low temperature. However, when applying high loaded reactors, the produced sludge is by definition not stabilised and needs further stabilisation in a separate digester. A novel technology consisting of an integrated high loaded reactor and digester for treating sewage at low temperature. The solices, which are entrapped in the sludge bed, are conveged to a digester operated at optimal conditions where they can be stabilised and the digested sludge is recirculated to the reactor to improve its methanogenic capacity. The ambient temperature flucluates between winter and summer, resulting in a sewage temperature of 10°C and 25°C.