基于厌氧膜生物反应器的剩余污泥-餐厨垃圾厌氧共消化性能

采用厌氧膜生物反应器(anaerobic membrane bioreactor,AnMBR)进行剩余污泥与餐厨垃圾的共消化,研究其有机物的去除特性、产气性能和微生物群落组成等运行性能.结果表明,反应器运行过程中有机负荷(organic loading rate,OLR,以VS计)稳定在0.59～0.64 kg·(m~3·d)~(-1),挥发性固体(volatile solids,VS)降解率由单消化17.5%上升至共消化40%,COD截留率为95.3%.消化液含固率提高了3.9倍,最终CH_4体积分数稳定在60%,CH_4产量(以COD_(added)计)为78.7 mL·g~(-1).跨膜压差(transmembrane pressure,TMP)和平均Flux分别维持在-3.1～-2.7 kPa和0.106 L·(m~2·h)~(-1),膜污染较轻.16S rRNA微生物多样性分析表明,AnMBR内部厌氧消化细菌主要是Proteobacteria(变形菌门)、Bacteroidetes(拟杆菌门)和Cloacimonetes(阴沟单胞菌门),产甲烷菌中的优势菌科为Methanobacterium(甲烷杆菌科),优势菌属为Methanosaeta(甲烷鬃毛菌属)和Methanolinea(甲烷绳菌属).这将为AnMBR处理污泥及其它高含固率废物流的稳定性和运行性能研究提供有力的理论参考依据,进而为生物质资源化和能源危机提供有效解决途径.

Performance of Anaerobic Membrane Bioreactors for the Co-digestion of Sewage Sludge and Food Waste

A laboratory-scale anaerobic membrane bioreactor (AnMBR) was used for the co-digestion of sewage sludge and food waste to investigate its organic matter removal characteristics, biogas production performance, and microbial community composition. The results showed that the degradation rate of volatile solids (VS) increased from 17.5% for a single digestion to 40% for the total digestion, and that the COD removal was 95.3% when the organic loading rate (OLR) was stabilized at 0.59-0.64 kg·(m³·d)^-1. The solids content of the digested sludge increased by a factor of 3.9. The final CH₄ content was 60% and the CH₄ yield was 78.7 mL·g^-1 of COD_added. The transmembrane pressure (TMP) and average flux were maintained at between -3.1 and -2.7 kPa and 0.106 L·(m²·h)^-1, respectively, and membrane fouling was not serious. According to an analysis of the microbial diversity using 16S rRNA, the anaerobic bacterium in the AnMBR were mainly phylum Proteobacteria, Bacteroidetes, and Cloacimonetes, and the dominant methanogens included the Methanobacterium family, Methanosaeta genus, and Methanolinea genus. This study provides a strong theoretical basis for research into the stability and performance of AnMBRs for the co-treatment of sludge and other high-solid waste streams, and provided an effective solution for biomass resource utilization and the energy crisis.