稻秸干式厌氧发酵气-肥联产潜力研究  

Study on the Potential of Rice Straw Dry Anaerobic Fermentation with Biogas and Fertilizer

作　　者：王晨 王振旗 张敏 沈根祥[1,2] 张心良 钱晓雍 高宗源 WANG Chen;WANG Zhen-qi;ZHANG Min;SHEN Gen-xiang;ZHANG Xin-liang;QIAN Xiao-yong;GAO Zong-yuan(School of Resources and Environmental Engineering,East China University of Science and Technology,Shanghai 200237,China;State Environmental Protection Key Laboratory of Environmental Health Impact Assessment of Emerging Contaminants,Shanghai Academy of Environmental Sciences,Shanghai 200233,China)

机构地区：[1]华东理工大学资源与环境工程学院,上海200237 [2]上海市环境科学研究院国家环境保护新型污染物环境健康影响评价重点实验室,上海200233

出　　处：《生态与农村环境学报》2022年第2期266-272,共7页Journal of Ecology and Rural Environment

基　　金：上海市科委“科技创新行动计划”项目(19DZ1204801);上海市重大环保科研项目(沪环科[2015]第8号,沪环科[2020]第10号)。

摘　　要：针对水源区稻秸长期还田引发的农业生产问题和环境风险,以及本地有机肥供应短缺问题,采用一体化不锈钢发酵罐,通过观测猪粪添加条件下稻秸干式厌氧发酵(含固率为20%)的产气特征和沼渣特性,探讨了高C/N比下稻秸气-肥联产潜力。结果显示,当反应体系C/N比升至50(C3组)时,日产气量最高为4.7 L·d^(-1),w(甲烷)达50%以上所需时间为12 d,单位干物质产气量为294 L·kg^(-1),仅比C/N比为30的最优组(C6组)下降了11.2%,说明稻秸干式厌氧发酵系统运行C/N比上限可设置为50;此外,稻秸干式厌氧发酵处理后C/N比为30~50的处理组(C3~C6)中纤维素可大幅降解,虽脱水沼渣总养分含量仅有2.25%~3.71%,但有机质含量、pH值和重金属含量均符合我国农业行业中NY/T 525—2021《有机肥料》标准要求,具备高品质有机肥料产品的生产潜力;经模拟工程测算,处理12 t·d^(-1)的秸秆年收益可达78.16万元,较现行的直接还田利用模式经济收益显著提高,说明水源区稻秸干式厌氧发酵气-肥联产具有可行性。To solve the long existing obstacles of following season growth and other environmental risks caused by rice straw returning to the field,as well as the issue of local organic fertilizer supply deficit in water resource area,a series of batch tests on an integrated stainless-steel anaerobic digester(with total solids of 20%)were conducted.The characteristics of both biogas and residue production from the studied dry anaerobic digestion(AD)system with limited pig manure(PM)input(as nitrogen source)were investigated,to explore the biogas and digestate productivity from AD systems with high C/N ratio.Results show that the maximum gas yield was 4.7 L·d^(-1) when C/N ratio reached 50∶1(group C3).On the 12 th day,the methane content in C3 group reached to 50%and biogas yield reached to 294 L·kg^(-1),which were only 11.2%lower than the optimal group C6(with C/N of 30∶1).It indicates that the upper limit of feedstock C/N ratio in dry AD system could be set at 50∶1.Moreover,the cellulose in C3~C6(with C/N ratio of 50∶1~30∶1)could also be significantly degraded after digestion processes.The total nutrient in the dehydrated digestate of different treatments(C3~C6)was only around 2.25%to 3.71%,but other criteria such as organic matter content,pH value and heavy metal contents could all meet the organic fertilizer standards NY/T 525-2021 in agricultural industry,thus could be processed to high-quality organic fertilizer products.Based on engineering process simulation,when rice straw was processed at a rate of 12 t·d^(-1),the annual profit of the studied system was 781600 yuan,which is significantly higher than the profit of direct returning of straw to field.Therefore,it′s considered both economically and environmentally feasible to apply biogas and fertilizer co-production from rice straw-based dry AD in water resource area.

关 键 词：水源区 水稻秸秆 共消化 干式厌氧发酵 制肥潜力 

分 类 号：X713[环境科学与工程—环境工程]