Preliminary evaluation of inhibitory effects of some substances on aerobic and anaerobic treatment plant biomasses

two biomasses coming from an aerobic activated sludge system and an anaerobic upflow sludge bed reactor, both operating in an industrial wastewater treatment plant. The aim was to obtain information about procedures to enhance the plant efficiency in the treatment of industrial wastewaters containing inhibitory compounds. To evaluate the aerobic biomass a respirometric test was used, as the anaerobic biomass was examined by methanogenic activity batch tests. Inhibition measures show similar results in experiments carried out with increased concentrations of the considered compounds on both biomasses. To control the reality of the toxicity assay procedures, high concentrations of NaOCl were tested among the other compounds during the study.