沼液全量回流对农业废弃物沼气发酵的影响  

Effect of full reflux of biogas slurry on biogas production with agricultural wastes

作　　者：陈广银 王恩慧 郑嘉伟 吴佩 刘旭 方彩霞 CHEN Guang-yin;WANG En-hui;ZHENG Jia-wei;WU Pei;LIU Xu;FANG Cai-xia(Anhui Engineering Laboratory of Soil and Water Pollution Control and Remediation,Wuhu 241002,China;School of Ecology and Environment,Anhui Normal University,Wuhu 241002,China)

机构地区：[1]安徽省水土污染治理与修复工程实验室,安徽芜湖241002 [2]安徽师范大学生态与环境学院,安徽芜湖241002

出　　处：《中国环境科学》2023年第S1期118-124,共7页China Environmental Science

基　　金：安徽高校协同创新项目(GXXT-2019-010)

摘　　要：为从源头实现沼液减量化,采用半连续进料方式,研究沼液全量回流用于农业废弃物沼气发酵的可行性.结果表明:纯秸秆沼气发酵过程中发酵液pH值、EC持续增加,总氮(TN)持续降低(第132d时仅为110mg/L),总挥发性脂肪酸(TVFAs)在94d后逐渐积累,日产气量逐渐下降,第104d时仅为产气稳定期时的50%,补氮后产气快速恢复,较补氮前大幅提高了1.5倍;与纯秸秆发酵相比,以秸秆猪粪混合物发酵避免了发酵过程中氮不足的问题,系统稳定性明显增强,且日产气量长期保持稳定,在沼液回流105d后TN和TVFAs有积累趋势,但对产气尚未表现出抑制.综上所述,在多元物料沼气发酵系统中进行沼液全量回流总体可行,但需关注铵氮和TVFAs累积问题.To realize the reduction of biogas slurry from the source,the feasibility of full reflux of biogas slurry for biogas production with agricultural wastes was studied at a CSTR reactor.The results showed that,the pH value and EC of the biogas slurry increased continuously,the total nitrogen(TN)content decreased to a low level(only 110mg/L on day 132)during the anaerobic mono-digestion of rice straw,and the content of total volatile fatty acids(TVFAs)accumulated gradually after day 94.Meanwhile,the daily biogas yield decreased gradually,and which was only 50%of that in the stable biogas production period on day 104.Insufficient nitrogen is an important reason for the decrease in the daily biogas yield during the anaerobic mono-digestion of rice straw with full reflux of biogas slurry.The daily biogas yield increased rapidly after nitrogen supplement and was 1.5times higher than that before nitrogen supplementation.Compared to anaerobic mono-digestion of rice straw,the stability of anaerobic co-digestion system of wheat straw and pig manure was significantly enhanced and the daily biogas yield was more stable.However,after 105days of full reflux of biogas slurry,the contents of TN and TVFAs in biogas slurry accumulated gradually while the daily biogas yield was still stable.In summary,it is feasible to conduct the full reflux of biogas slurry to the anaerobic system in the multi-material biogas plant,but attention should be paid to the accumulation of ammonium nitrogen and TVFAs.

关 键 词：厌氧消化 沼气 沼液回流 氮 农业废弃物 

分 类 号：S216.4[农业科学—农业机械化工程] X71[农业科学—农业工程]