Mathematical modeling of trichloroethylene (TCE) degradation in membrane-attached biofilms

A mathematical model for the counter-diffusional membrane-attached methanot rophic biofilm reactor was developed. The model included competitive inhibi tion between trichloroethylene (TCE) and methane, production of inactive ce lls by TCE byproduct toxicity, and biomass detachment as a function of inac tive cell concentration. Simulation results indicated that the optimum oxyg en to methane ratio was dependent on the biofilm and the membrane thickness . Furthermore, the model confirmed experimental observations that the effic iency of the process is not limited by competitive inhibition or substrates mass transfer, but by the back-diffusion of TCE through the membrane and t he consequent TCE accumulation in the gas phase.