Removal Of Xylene From Simulated Waste Gases By Two-liquid-phase Bioreactor

Two-liquid-phasebioreactor (TLPB) is a new technology for waste gas treatment. The removal capacity of xylene of TLPB was enhanced by adding dimethyl silicone into inorganic salt solution. In this thesis, the removal of gas-phase o-xylene waste gas by TLPBs was studied. It was expected that this study could provide theoretical foundation and basic data for the industrial application of this new approach.Dimethyl silicone oil was selected as a non-aqueous phase to enhance the absorption. The effecet of two-phase system on solubilization of o-xylene was investigated. The optimum volume ratio of silicone oil in the nutrient solution was5%in present study. The existence of silicone oil had no significant effect on the biodegradation of o-xylene according to the toxicity test.Two common bioreactors, biotrickling filter and airlift bioreactor, were selected and transformed to TLPBs by adding5%(v/v) of silicone oil. The effect of gas residence time, inlet concentration, inlet capacity and concentration fluctuation were investigated. The results showed that the removal efficiency of TLPBs was better than those of corresponding traditional bioreactors. In addition, it indicated that airlift bioreactor had more advantages compared to biotrickling filter.The microbial community structure in the biological reactor was analyzed by molecular biology techniques. The results showed that the microorganmisms was dominanted in the bioreactor were Family Chitinophagaceae, Comamonas gene and Novosphingobium gene.