Fermentative hydrogen production from wastewater and solid wastes by mixed cultures

Over 160 publications related to fermentative hydrogen production from wastewater and solid wastes by mixed cultures are compiled and analyzed. Of the 98 reported cases, 57 used single substrates (mainly carbohydrates), 8 used actual wastewater, and 33 used solid wastes for hydrogen conversion. The key information is compiled in four tables: (1) pretreatment conditions for screening hydrogen-producing bacteria from anaerobic sludge or soil, and the process and performance parameters for (2) single substrates in synthetic wastewaters, (3) actual wastewaters, and (4) solid wastes. Process parameters discussed include pH, temperature, hydraulic retention time, seed sludge, nutrients, inhibitors, reactor design, and the means used for lowering hydrogen partial pressure. Performance parameters discussed include hydrogen yield, maximum volumetric production rate, maximum specific production rate, and conversion efficiency. The outlook for this new technology is discussed at the end.