Methane Production Potential of Rumen Pretreated Lignocellulosic Wastes

Bioenergy production from lignocellulosic biomass is challenging due to its structure and a pretreatment is required before methane production. In this study, biological pretreatment by using rumen microorganisms was applied for different types of lignocellulosic wastes: wheat straw, cotton stalk, reeds and sunflower stalk. The reactors were pretreated for 2, 5, 10, 15 and 20 days. After the pretreatment stages and gas measurements were done, reactors were separated into two phases as lower solid phase and upper liquid phase. The reactors were installed for the methanation stage, gas measurements were made at regular intervals and graphs were drawn using the cumulative results. Modified Gompertz equation was used to estimate potential biogas production. According to the results, the reactor containing 5 days pretreated wheat straw became prominent among the other reactors in terms of biogas and methane production with 163 ml and 102 ml, respectively. It was followed by 20 days pretreated reeds with 104 ml biogas and 80 ml methane, 2 days pretreated sunflower stalk with 88 ml biogas and 52 ml methane, and 2 days pretreated cotton stalk with 87 ml biogas and 50 ml methane.