EFFECT OF SODIUM HYDROXIDE SOLID STATE PRETREATMENT ON PHYSICOCHEMICAL CHARACTERISTICS OF RICE STRAW FOR ENHANCING BIOGAS PRODUCTION
Pretreatment of rice straw with NaOH in solid-state was highly effective in improving biodegradability and enhancing biogas production. The chemical compositions, chemical structures and physical structures of rice straw before and after anaerobic digestion (AD) were analyzed using Fourier transform infrared spectroscopy (FTIR) to explore the effect of NaOH pretreatment on AD of rice straw to improve biogas yield. It was found that the methane yield of NaOH-treated rice straw was increased by 30.3％-62.7％. The enhancement of methane yield was attributed to the improvement of biodegradability through NaOH pretreatment. Degradation of 16.4％ cellulose, 36.8％ hemicellulose, and 28.4％ lignin was observed. After AD, both the untreated and NaOH-treated rice straw were degraded obviously, but the degradation rates of cellulose, hemicellulose and total lignocellulose of the NaOH-treated rice straw increased more 44.0％, 16.3％, and 30.0％ than that of the untreated rice straw, respectively. The linkages of interunits and the functional groups of cellulose were either broken down or destroyed during NaOH treatment and AD, causing intramolecular and intermolecular changes of chemical structures. The analyses on cellulose crystallinity showed that the infrared crystallization index (ICI) of NaOH-treated rice straw after AD was smaller than that of untreated rice straw after AD due to the role of NaOH. The changes of chemical compositions, chemical structures, and physical characteristics made rice straw become more available and biodegradable and thus were responsible for the enhancement of biogas yield.
Rice straw Solid-state pretreatment Anaerobic digestion Sodium hydroxide Structural change
Yan-feng HE Xiu-jin LI Yan-ping LIU Ming-xia ZHENG
Department of Environmental Science and Engineering,Beijing University of Chemical Technology,Beijing,P.R. China,100029
国际会议
广州
英文
1428-1434
2008-12-03（万方平台首次上网日期，不代表论文的发表时间）