Abstract
Authors have been studied to clear characteristics of pretreated wheat bran as a typical fibrous biomass for a substrate of methane fermentation and conducted some experiments under various conditions in order to exchange biomass into energy through methane fermentation. In this paper, untreated wheat bran was selected for decreasing cost and labor of pretreatment. The objective in this paper was to clear characteristics of untreated wheat bran in detail in order to maintain the steady operation through continuous methane fermentation. As a result, the maximum organic loading rate was obtained about 2.5 [g-TS/L/day] to maintain the steady fermentation under mesophilic methane fermentation with 50L fermenter using untreated wheat bran. This value was much lower than that of obtained with 1L fermenter using pretreated wheat bran. The reason was considered to need more time for hydrolyzing untreated wheat bran and to give more harmful influences to bacteria with high organic loading rate. However, this value was about same as that of ordinary mesophilic methane fermentation using livestock manure. Therefore, it's cleared that methane fermentation is useful for energy conversion process from a fibrous biomass.
