Process for purifying waste water in an activation tank

摘要

Process for purifying waste water (effluent) in an activation tank. nown waste water purification processes which degrade nitrogen compounds with the aid a nitrification phase and a subsequent denitrification phase have the disadvantage that they cannot operate in a load-dependent manner and thus cannot operate optimally. According to the invention it is provided to determine each of the time periods for the nitrification phase and denitrification phase in dependence on the amount of oxygen introduced into the activation tank, the power requirement of the aeration device which is assigned to the activation tank being able to serve in a simple manner as a value for the (O2) feed. The novel plants therefore operate in a load-dependent manner. Application for sewage treatment plants having spatial loadings below 0.25 kg BOD5 per m<3>. <IMAGE>