Kinetics and stoichiometry of SBR/denitrification with a primary sludge carbon source

Abstract

Primary sludge from domestic wastewater was shown to be an excellent feed stock for separate stage denitrification processes. Biological solids were obtained from laboratory SBR activated sludge processes operated at solids retention times of 6, 12, and 24 days. The biological solids were added to solutions of nitrite, nutrients, and selected substrates (dextrose, acetate, carboxymethyl cellulose, and primary sludge). Denitrification rates were determined with batch reactors. Values of the denitrification rate observed compare favorably with those for acetate and dextrose. Rates with carboxymethyl cellulose were similar to those associated with endogenous respiration.