The overall energy recovery from tw

The overall energy recovery from two stages is
equivalent to 6.9 x 10-3 kW-h, which increased by 81% compared to that recovered from one stage fermentation 3.8
x 10-3 kW-h). The finding suggested that the first stage of hydrogen fermentation plays significant role in the
overall improvement of degradation efficiency and biogas recovery. Separation of combined hydrolysis,
acidogenesis, and acetogenesis in the first stage from the second stage fermentation allows more flexibility in
controlling of fermentation conditions and could be more beneficial for simultaneous treating and extracting
complex organic feedstocks or recalcritant organic matters.