Improving two-stage thermophilic-mesophilic anaerobic co-digestion of swine manure and rice straw by digestate recirculation.

摘要: Abstract The anaerobic co-digestion (coAD) of swine manure (SM) and rice straw (RS) is appealing for renewable energy recovery waste treatment worldwidely. Improving its performance very important application. In this study, long-term semi-continuous experiments were conducted to evaluate the improving effects digestate recirculation on performance, recovery, microbial community two-stage thermophilic-mesophilic coAD (RS). experimental results indicated that systems SM RS (mixing ratio 3:1) with or without could not realize phase separation. reactors both characterized by pH values ranging from 7.74 7.85, methane production as 0.41 ± 0.02 0.44 ± 0.03 L/L/d, stable operation. Notably, increased total production, organic matter removal, reaction rate system 9.92 ± 5.08, 5.22 ± 1.94, 9.73–12.60%, respectively. Digestate improved significantly increasing abundance Methanosarcina (from 4.1% 7.5%–10.7% 35.7%) decreasing Methanothermobacter 94.2% 87.3%–83.6% 56.8%). Thus, main methanogenesis pathway was changed effectively improved. Although input 30.26%, balance 6.83%.