Performance analysis of a proton exchange membrane fuel cell (PEMFC) integrated with a trickling bed bioreactor for biological high-rate hydrogen production

For the performance investigation of a biohydrogen reactor integrated with a proton exchange membrane fuel cell (PEMFC), mesophilic trickling bed bioreactors (TBRs) filled with hydrophobic materials (HBM) were designed and conducted for hydrogen production under the anaerobic fermentation of sucrose. The bioreactor consisted of the column packed with polymeric cubes and inoculated with heat-treated sludge obtained from an anaerobic digestion tank. A defined medium containing sucrose was fed by the different hydraulic retention time (HRT) and recycle rate. Hydrogen concentrations in the gas phase were constant, averaging 40% of biogas throughout the operation. The hydrogen production rate (HPR) was increased until 10.5 LH₂ L^-1 h^-1 of the bioreactor when influent sucrose concentrations and recycle rates were varied. No methane was detected when the reactor was under a normal operation. The trickling bed bioreactor with hydrophobic materials demonstrates the feasibility of the process to produce hydrogen gas, and PEMFC was operated with the treated biogas from the reactor as a fuel source. A likely application of this reactor technology can be hydrogen gas recovery from the pretreatment of high-carbohydrate-containing wastewaters and the electricity generation using the fuel cell system with employment of the produced biogas.