BIOLOGISKT BEHANDLINGSSYSTEM FOER SPILLVATTEN

摘要

In an activated sludge system, activated biomass is mixed with BOD-contg. waste water influent in a BOD sorption zone to produce a mixed liquor with less than 5% of the total BOD5 oxidised. The BOD contained in the mixed liquor is subsequently oxidised in an oxidation zone under controlled aeration conditions such that at least 30% of total influent BOD5 is oxidised. The oxidised mixed liquor is settled to separate supernatant liquor from the more dense sludge including biomass. A portion of the sludge is recycled to provide activated biomass in the initial BOD sorption zone. Used for treatment of municipal sewage and industrial waste water by the activated sludge process. Operation of the system at high influent throughput rate minimises the external O2 requirement for BOD removal. -