Accumulation of Soluble Microbial Products in Membrane Bioreactor and Its Influence to Bioreactor Operation

Accumulation of SMP in the membrane bioreactor(MBR) and its influence to bioreactor operation were studied.The result showed that the predominant constituent of SMP was carbonhydrate in the bioreactor during steady state.Furthermore,compared to the conventional activated sludge process(CAS),concentrations of SMP were higher in the MBR due to efficient interception performance of the membrane.It was found that the accumulation of SMP in the MBR had adverse effect on sludge MLVSS/MLSS value and dehydrogenase activity,and microbial metabolism activity was restrained.During steady state,the concentration of protein and carbonhydrate in the effluent and mixture supernatant respectively contributed to 95% and 64% of the TOC.SMP were main pollutants of mixture supernatant and effluent in the MBR.