Abstract
Methane fermentation was carried out to produce methane from lignocellulosic waste, i.e. soybean curd refuse, bamboo, and Japanese cedar. Soybean curd refuse was fermented directly using methanogens sludge. Bamboo and Japanese cedar were pretreated by steam explosion and then fermented using methanogens sludge. The steam explosion was effective for the delignification of bamboo and Japanese cedar, and enhanced the methane production from lignocellulosic waste. About 300 mL methane gas was produced from 1 g soybean curd refuse. The maximum amounts of methane gas produced, i.e. 237 and 108 mL, were obtained from 1g steam-exploded bamboo (Steam pressure of 3.5 MPa and steaming time of 5 min) and steam-exploded Japanese cedar (Steam pressure of 3.5 MPa and steaming time of 10 min), respectively. Since about 420 mL methane gas are produced from 1 g holocellulose, according to Buswell's theory, the yield of methane produced from holocellulose in the steam-exploded bamboo (holocellulose content: 0.71 g) and Japanese cedar (holocellulose content: 0.44 g) corresponded to about 80 and 60 % of the theoretical value, respectively.
