Anaerobic digestion has become an established and proven technology for the treatment of organic wastes such as municipal solid waste, industrial organic waste, animal manure, and agricultural residues. The main advantage of this process is that the product can be used as a vehicle fuel or for co-generation of electricity and heat, and thus, can lead to reductions in greenhouse gas emissions.In China, rice straw (RS) is one of the most abundant agricultural residues, with quantities estimated between 180 and 270
million tons based on dry content in 2007 (Yanli et al., 2010). Large amounts of RS, however, are burned or discarded resulting in environmental pollution. Numerous studies have been carried out using agricultural residues as mono-substrates for biogas production(Khalid et al., 2011; Salminen and Rintala, 2002); however,the direct utilization of rice straw by microorganisms is difficult because of their unbalanced nutritional properties (C/N) and recalcitrant lignocellulosic structure (Himmel et al., 2007). Therefore,attention has been increasingly focused on improving biogas production
of lignocellulosic materials through various pretreatments