College of Engineering, Shenyang Agricultural University, Shenyang 110866, China.
Biomass Energy Engineering Research Centre, School of Agriculture and Biology, Shanghai Jiao Tong University, 800 Dongchuan Road, Shanghai 200240, China.
Int J Environ Res Public Health. 2023 Jan 17;20(3):1687. doi: 10.3390/ijerph20031687.
Slurry reflux is a low-cost slurry reduction technology, which can solve the problem that a large amount of slurry cannot be completely consumed in a biogas plant. Anaerobic digestion (AD) of corn stalks with slurry reflux and non-reflux was compared and evaluated in continuous anaerobic digestion to clarify the effects of slurry reflux on AD with organic loading rate (OLR) variation. It was found that slurry reflux increased cumulative methane production and improved system stability. The average methane yield of the slurry reflux group was 224.19 mL/gVS, which was 41.35% higher than that of the non-reflux group. High-throughput sequencing results showed that slurry reflux increased the microbial community richness. The dominant microorganisms in the reflux group were in phylum Bacteroidetes, which have the capacity to degrade polymers, and , which is an aceticlastic methanogen. The relative abundances of Bacteroidetes and were 32.41% and 41.75%, respectively. III and , which are related to syntrophic acetate oxidation and hydrolysis, were increased in relative abundance in the slurry reflux system. The increase of the OLR altered the main methane-producing pathway from the acetoclastic methanogenic pathway to the hydrogenotrophic methanogenic pathway in the AD system, and the slurry reflux can delay this trend. This study provided an effective way for the reduction and utilization of slurry in a biogas plant.
料浆回流是一种低成本的料浆减量化技术，可以解决沼气工程中大量料浆无法完全消耗的问题。采用连续厌氧消化技术比较和评价了有料浆回流和无料浆回流的玉米秸秆厌氧消化，以阐明料浆回流对有机负荷率（OLR）变化的厌氧消化的影响。结果表明，料浆回流提高了累积甲烷产量，改善了系统稳定性。料浆回流组的平均甲烷产率为 224.19 mL/gVS，比无回流组高 41.35%。高通量测序结果表明，料浆回流增加了微生物群落的丰富度。回流组中的优势微生物在门水平上属于拟杆菌门，具有降解聚合物的能力，而属于乙酸营养型产甲烷菌。回流组中拟杆菌门和的相对丰度分别为 32.41%和 41.75%。与协同乙酸氧化和水解有关的 III 和 在料浆回流系统中的相对丰度增加。OLR 的增加改变了 AD 系统中主要的产甲烷途径，从乙酸营养型产甲烷途径转变为氢营养型产甲烷途径，而料浆回流可以延缓这种趋势。本研究为沼气工程中料浆的减量化和利用提供了一种有效的方法。
