The Study of Organic Removal Efficiency and Membrane Fouling in a Submerged Membrane Bioreactor Treating Vegetable Oil Wastewater

The characterizations of vegetable oil wastewater (VOW) are unpleasant odor, dark color, and high organic contents, including large amounts of oil and grease (O&G), chemical oxygen demand (COD), fatty acids and lipids. Therefore, VOWs should be treated efficiently to avoid the environmental pollution. The aim of the present study was the investigation of VOW biological treatment using membrane bioreactor (MBR) in terms of organic pollutant removal performance and membrane fouling. During 30 days MBR operation at hydraulic retention time and solid retention time of 48 h and 20 days, respectively, there was a consistently low turbidity (<2 NTU) in the MBR effluent. The COD and O&G removal efficiency from the wastewater using the MBR were 85.0±1.3% and 82.7±1.4%, respectively. With decrease in aerobic metabolic activity and hence the activated sludge growth rate during the MBR operation, the MLSS and MLVSS decreased and led to accumulation ofO&G and soluble microbial products (SMP) inside the bioreactor. The effluent COD value and the transmembrane pressure during the MBR operation remained in the range 88.7±11.5 mg L-1 and 1-2 kPa, respectively. The current study shows that the MBR has a very good potential for treatment of VOW, both in terms of removal performance and membrane fouling

کلیدواژه ها:

Membrane Bioreactor ، Vegetable Oil Wastewater ، Biological Treatment ، Organic Pollutant Removal ، Membrane Fouling