Generation of soluble microbial products in membrane bioreactor under nutritional deficiency.

In order to investigate the regularity and characteristics of the product of SMP under nutrient deficiency,and to provide theoretical basis for optimizing MBR reactor's operation and lessening membrane fouling,this research is done under the oligotrophic environment using the sludge from the MBR of Tianjin University.Results show that production of SMP could be divided into two stages under nutrient deficiency including dissolved of EPS produced SMP and splited of dead cell proucted SMP.Accompanied by nutrient deficiency,SMP of macromolecular material has a significant increase in the proportion.From the third day of 20.2% (the proportion of the total TOC),the eighth day rose to 39.2%,which would aggravate membrane fouling,and SMP produce in different stages can stimulate the microorganisms to increase the rate of degradation of the substrate.