The use of chemical uncouplers to reduce biomass production in the activated sludge process

The use of chemical inhibitors to uncouple bacterial catabolism and anabolism in the activated sludge process was investigated, in an attempt to lower biomass production. Toxicity testing investigated the oxygen uptake of treated samples. Several candidate chemicals (2,4-Dinitrophenol (2,4-DNP), rotenone) were found. Testing for oxygen uptake was carried out in a respirometer. Further work investigated the effect on the COD removal and biomass of the activated sludge. Results suggested that at an optimum dose, uncoupling could be achieved whilst the COD removal remained comparable to that of the control samples.