Integrated biological hydrogen production

Enhancement of Bio-Hydrogen Production in Chlamydomonas Reinhardtii by Immobilization and Co-Culturing

“…Photosynthetic hydrogen production by green microalgae uses the visible region of light spectrum (400-700nm), whereas ragi tapai which contains a mixture of microorganism uses the near infrared region (700-950nm) of the solar spectrum [40]. Hence combination of both microalgae and ragi tapai broadens the range of solar spectrum allowing improved utilization of the light for photobiological hydrogen production [9].…”

Photobiological Solar Energy Harvest

“…In a sealed, sulfur depleted environment, algae will stop oxidizing water, thus ending the supply of oxygen. When the remaining oxygen is consumed, the algae begin metabolizing stored compounds in an alternative respiration system from which hydrogen is evolved as the product (Melis & Melnicki, 2006). The catalysts for this reaction are either the hydrogenase or the nitrogenase enzymes, whose activities are inhibited by elevated oxygen levels in the environment.…”

Photofermentative Hydrogen Generation in Presence of Waste Water from Food Industry

“…High concentration of N-NH 4 + as well as N 2 inhibits hydrogen production by nitrogenase. In the absence of nitrogen in the system the nitrogenase catalyses the reduction of protons to molecular hydrogen (Melis, 2006, Yakunin, 1988, Pawlowski, 2003, Dubbs, 2004.…”

“…In case of brewery waste with low COD (27 g O 2 /l) only 0.67 l of H 2 per l medium was produced (waste concentration 80 % v/v). If higher concentrations of wastes were applied, the efficiency of hydrogen production was lower, which was caused by and inhibiting concentration of N-NH 4 + (40 mg/l for dairy waste and 96 mg/l for brewery waste) (Waligórska, 2009, Melis, 2006. Such concentration of ammonium ions can diminish significantly the overall generation of hydrogen .…”