Kinetics of rice straw methane fermentation

Abstract

The kinetics of anaerobic fermentation of rice straw to methane were studied. Rice straw was the only carbon source at influent volatile solid concentrations of 18.9 and 37.8 g/l. Semicontinous runs were carried out at 37°C in laboratory scale perfectly mixed reactors. The Contois' kinetic model constants were calculated from the experimental data. Arefrac tory coefficient was measured (R=0.374) to account for the nonbiodegradable portion of the organic matter of rice straw and incorporated into the kinetic equations. The predicted values of effluent substrate concentration, volumetric methane yield, volumetric methane production rate, and biodegradable conversion efficiency fit well with those measured experi mentally.