Model of a polyethylene microporous hollow-fiber membrane biofilm reactor inoculated with Pseudomonas putida strain To1 1A for gaseous toluene removal

A diffusion and reaction model is presented for a gas phase membrane biofilm reactor (MBfR) that overcomes many of limitations of conventional biofilters. The model considers transfer of toluene from the gas phase through the membrane and into a toluene degrading biofilm. Data from bench-scale tests of toluene removal in an MBfR were used to validate the model. Overall mass transfer coefficients were 0.64 × 10−3, 1.1 × 10−3, 1.86 × 10−3 (m s−1) at liquid flow rates (shell-side) of 4, 7, and 9 L min−1, respectively. Modeled mass transfer coefficients were in good agreement with experimental values. The bench-scale MBfR was capable of removing more than 98% of the influent toluene (an overall removal rate of 17 g m−3 min−1) at an inlet concentration of 100 ppmv and a gas flow rate of 1.0 L min−1 (gas residence time of 1.3 s in the membrane lumen). Model predictions were well in agreement with experimental values.