Influence of organic loading rate on membrane fouling in membrane separation activated sludge process

A Laboratory-scale experiment was conducted to investigate the influence of organic loading rate to a reactor on the bio fouling in a membrane separat ion activated sludge system. A flat-sheet-type membrane module was used and the change of the pressure and the filtration resistance were measured. Us ing synthetic substrate, TOC loading rate was set in the range between 0.3 g l(-1) day(-1) and 1.5g l(-1) day(-1) Also an experiment on the consolidat ion characteristics of sludge accumulated on membrane was conducted. A math ematical model was developed to simulate temporal changes of suction pressu re, flux and filtration resistance considering accumulation, detachment and consolidation of bacterial extracellular polymers on the membrane surface. A reactor with higher loading rate showed sudden increase of transmembrane pressure, while a reactor with lower loading rate showed delayed increase of the pressure. The experimental results were simulated well by the develo ped model.