Effect of Temperatures on Hydrolysis Efficiency and Subsequent Methane Production of Rice Straw Degraded by Domesticated Paddy Soil Microbes

Rice straw (RS) is treated by straw biogas anaerobic digestion (AD) technology to reduce pollution, but RS anaerobic gas production technology has some problems such as low gas production rate, slow digestion speed, and long digestion period. Domesticated paddy soil microbes (DPSM) is an effective biological pretreatment technology that can improve the efficiency of AD of RS. This study aims to select the optimum temperature conditions for hydrolysis of RS from 25 ℃, 37 ℃, and 55 ℃. The results show that at 37 ℃, the COD value reached the peak value on day 3 of the hydrolytic acidification period, and the organic acid content reached 4134.548 mg/L on day 15. Considering material consumption and organic acid accumulation, the hydrolysate on day 3 of 37 ℃ was selected for AD. Compared with the control group, the total amount of methane produced by AD increased by 13%, and the AD period was shortened by 10 days. This study provided technical guidance for the application of composite bacteria in the pretreatment of lignocellulosic raw materials