Effect of Nutrient Supply on the Production of Soluble Microbial Products(SMP) in Anaerobic Reactors

Three up-flow anaerobic sludge blanket (UASB) reactors added with different amount of nutrients were compared to investigate the effect of nutrient on the production of soluble microbial products (SMP) in the bench-scale anaerobic reactors. The running performance and the analysis of SMP verified that the nutrient level could greatly affect the treatment performance and the quality of anaerobic effluent. The surplus nutrimental addition would stimulate the bacterial activity and increase the metabolism products, causing the high concentration of effluent organic matter. On the contrary, the nutrient deficiency could keep the microbial activity at a low level, which caused the temporary better anaerobic effluent at the low organic loading rate (OLR), but might lead to a vulnerable microbial system, even system failure when OLR went higher. Molecular analysis revealed that the abundant existence of Methanosaeta might be beneficial to the SMP consumption.