Quantification of air stripping and biodegradation of organic removal in acrylonitrile-butadiene-styrene (ABS) industry wastewater during submerged membrane bioreactor operation

With the rapid development of the petrochemical industry in Taiwan, a significant amount of nitrogenous organic wastewater is generated. Some of this wastewater contains volatile residual monomers, such as acrylonitfile-butadiene-styrene (ABS) manufacturing wastewater. Because of the high volatility of the acrylonitrile monomer, this chemical will be partly removed from the aeration system by the air stripping effect. An empirical model was developed for evaluating BOD removal by air stripping and biodegradation when the wastewater was treated in an aerobic submerged membrane bioreactor (ASMBR). The results showed that the removal of BOD from ABS wastewater by air stripping was in the range of 2-10%. These results also showed that the estimation of contribution of air stripping and biodegradation in the BOD removal in the MBR is very important in the optimum design of the MBR for ABS wastewater.