Effect of Particle Size on the Aerobic and Anaerobic Digestion Characteristics of Whole Rice Straw

The effect of reducing particle size on physical properties, the methane yield and energy flow were investigated through biochemical potential (BMP) experiment aerobic-anaerobic digestion (AAD) rice straw (RS). whole was crushed four sieves different aperture sizes (1, 3, 5, 7 mm) to obtain actual non-uniform distribution (PSD). results indicated that normally or logarithmic distributed. Reducing could significantly promote aerobic hydrolysis acidification process, increase content volatile fatty acids (VFAs) from 4408.78 6225.15 mg/L degradation solids (VS) 40.56% 50.49%. path analysis suggested reduction played an important role in improving lignocellulosic degradability, which main factor affecting production with comprehensive decision 0.4616. maximum obtained at 1 mm sieve 176.47 mLCH4g?1 VS. phyla Firmicutes (61.5%), Proteobacteria (9.3%), Chloroflexi (8.3%), Bacteroidetes (4.1%), Cyanobacteria/Chloroplast (4.6%) mainly responsible for VFAs lignocellulose degradation. However, net negative balance observed due increased input. Therefore, optimum AAD 3 mm.