MEMBRANE BIOREACTOR WITH A POROUS HYDROPHOBIC MEMBRANE AS A GAS-LIQUID CONTACTOR FOR WASTE-GAS TREATMENT

A novel type of bioreactor for waste gas treatment has been designed. The reactor contains a microporous hydrophobic membrane to create a la rge interface between the waste gas and the aqueous phase. To test the new reactor, propene was chosen because of its high air/ water partit ion coefficient, which causes a low water concentration and hampers it s removal from air. Propene transfer from air to a suspension of prope ne-utilizing Xanthobacter Py2 cells in the membrane bioreactor proved to be controlled by mass transfer in the liquid phase. The resistance of the membrane was negligible. Simulated propene transfer rates agree d well with the experimental data. A stable biofilm of Xanthobacter Py 2 developed on the membrane during prolonged operation. The propene fl ux into the biofilm was 1 x 10(-6) mol m(-2) s(-1) at a propene concen tration of 9.3 x 10(-2) mol m(-3) in the gas phase. (C) 1995 John Wile y & Sons, Inc.