Biological hydrogen production from an unsaturated, packed-bed bioreactor

Biohydrogen production through dark fermentation provides an economical alternative to costly aeration processes for wastewater treatment. The generated hydrogen can be captured and used in fuel cells. The design and testing of a trickle-bed hydrogen-producing bioreactor was presented. The reactor was packed with glass beads to allow biofilm to build up from a pure culture inoculum, Clostridium acetobutylicum. Gas-phase hydrogen concentrations of 74-79% were obtained at influent glucose concentrations of 3.3-10.5 g/L. The hydrogen production rate ranged from 23.5 to 27.3 mL/hr. The measured hydrogen yields indicated an overall conversion efficiency of 17-22% based on a theoretical stoichiometry of 4 moles hydrogen from 1 mole of glucose. This is an abstract of a paper presented at the 228th ACS National Meeting (Philadelphia, PA 8/22-26/2004).