Chemical treatment systems of night soil are characterized by a smaller scale of the primary treatment process than other treatment systems. Treatment at lower dilutions with a high load is therefore desirable in the secondary treatment process as well.
By the activated sludge process, biochemical oxygen demand (BOD) is easily removed from the supernatant liquor produced by the primary treatment, such that treatment without dilution at a high load may be sufficient.
This study consists of the treatment of the supernatant liquor produced by the primary treatment in the nightsoil chemical treatment system, using an activated sludge process without dilution at high load in order to study the design dimensions such asloading conditions, oxygen requirement and sludge production.