生物-非生物添加剂协同促进餐饮业厨余垃圾厌氧消化——产气效能及微生物菌群动态变化

A synergistic promotion during anaerobic digestion of food waste generated from catering industry by the bio-abiotic additives——Biogas production efficiency and corresponding microbial dynamic changes

围绕当前餐饮业湿热除油厨余垃圾(FORFW)厌氧消化甲烷产率不高、“酸积累”和“氨抑制”导致过程不稳定的问题,基于生物-非生物协同强化湿热除油餐饮业厨余垃圾厌氧消化的课题组的前期发现,通过三因素三水平中温厌氧消化正交试验系统探究并优化接种比、铁类添加剂添加量和酵母菌添加量3个条件参数,同时借助高通量测序阐明生物-非生物添加剂协同促进FORFW产甲烷的内在微生物机理.研究发现,3个条件参数对FORFW厌氧消化的甲烷产率影响由高至低为接种比>酵母菌添加量>铁类添加剂添加量.接种比1.5、铁类添加剂0.5%(质量分数)、活化酵母菌3%(质量分数)为较优的使用条件.在上述条件下,FORFW的挥发性固体(VS)去除率为40.1%,累积甲烷产率为237.5mL/gVS.体系中甲烷鬃毛菌属(Methanosaeta)、互营单胞菌属(Syntrophomonas)和Syner-01属相对丰度明显增加,实现了乳酸来源的丙酸高效转化.其中,甲烷鬃毛菌属与厌氧绳菌科细菌互营产甲烷,互营单胞菌属参与互营丁酸氧化,Syner-01属参与互营乙酸氧化和氨基酸氧化.因此,FORFW的甲烷产率得到了切实保证.

The aim of this study was to solve the problem of unstable process induced by low methane production rate,"acid accumulation"and"ammonia inhibition"in the anaerobic digestion of floatable-oil recovered food waste(FORFW)generated from the catering industry.Based on our previous research that combined bio-abiotic addition could enhance the anaerobic digestion of food waste synergistically,a three factors-three levels orthogonal experiment of mesophilic anaerobic digestion was conducted in this study to investigate and optimize reaction parameters,including inoculum ratio,iron addition amount and yeast amount.The intrinsic microbial mechanism of synergistic promotion of bio-abiotic additives in FORFW methanogenesis was elucidated by the high throughput sequencing technique.It was found that the influence of three parameters on the methane yield of FORFW anaerobic digestion:inoculum ratio>yeast amount>iron addition amount.The optimal condition were inoculation ratio of 1.5,iron addition of 0.5%(w/w)and activated yeast of 3%(w/w).Under the optimal condition,the VS removal rate of FORFW was 40.1%,and the accumulative methane yield was 237.5mL/g VS.The relative abundance of genera Methanosaeta,Syntrophomonas,and Syner-01 increased significantly in the system,resulting in efficient conversion of lactic acid-derived propionic acid.Genus Methanosaeta interacted with Anaerolineaceae in syntrophic methanogenesis,Syntrophomonas was involved in butyric acid oxidation process,while Syner-01 participated in acetic acid oxidation and amino acid oxidation.Thus,the methane yield of the FORFW generated from the catering industry was ensured.The research results will provide scientific guidance for further practical application and process control.