中温和高温环境下乙酸和丙酸厌氧发酵产甲烷动力学特征  

Methanogenesis kinetics of anaerobic digestion of acetate and propionate at mesophilic and thermophilic conditions

作　　者：乔玮[1,2] 姜萌萌 赵婧[1,4] Wandera S.M 董仁杰[1,2,3] Qiao Wei;Jiang Mengmeng;Zhao Jing;Wandera S.M;Dong Renjie(College of Engineering,China Agricultural University,Beijing 100083,China;R&D Center for Efficient Production and Comprehensive Utilization of Biobased Gaseous Fuels,Energy Authority,National Development and Reform Committee(BGFeuls),Beijing 100083,China;Institute of Yantai,China Agricultural University,Yantai 264670,China;Faculty of Science and Engineering,University of Groningen,Groningen,9747 AG The Netherlands)

机构地区：[1]中国农业大学工学院,北京100083 [2]国家能源生物燃气高效制备及综合利用技术研发(实验)中心,北京100083 [3]中国农业大学烟台研究院,烟台264670 [4]荷兰格罗宁根大学科学与工程学院,格罗宁根9747AG

出　　处：《农业工程学报》2018年第21期234-238,共5页Transactions of the Chinese Society of Agricultural Engineering

基　　金：“十三五”国家重点研发计划课题(2016YFD0501403);国家自然科学基金课题(51778616、51408599);北京市自然科学基金(6182017)。

摘　　要：采用不同浓度的乙酸和丙酸在中高温下进行厌氧发酵批次试验,采用修正的Gompertz模型和产甲烷的一级动力学模型分析,研究酸浓度和温度对发酵产气动力学的影响。研究表明,当乙酸和丙酸浓度较低时降解较快,高浓度酸抑制产气。乙酸在中温条件下降解较快,质量浓度为5 000 mg/L时中温反应有最大产甲烷速率101 mL/d;质量浓度为10 000mg/L时高温条件下有最大产甲烷速率77mL/d,随酸浓度增加,最大产甲烷速率减小,高温反应器对酸的耐受度较高。丙酸在高温条件下更易降解,浓度为4 000 mg/L时,中高温反应均有最大产气速率:78 mL/d(中温)和96 mL/d(高温)。另外,高浓度乙酸和丙酸厌氧降解产气具有滞后性,且随酸浓度的增加滞后期延长,降解过程受到抑制,一级动力学常数减小。温度对厌氧降解的影响大于酸浓度对厌氧降解的影响。During anaerobic fermentation is strongly influenced by temperature and volatile fatty acids(VFAs).When the temperature in anaerobic reactors is too high,the VFAs are easy to accumulate,especially acetate and propionate.High VFAs will inhibit the activity of methanogens,the fermentation process as well as the methane yield will become unstable even make the anaerobic system failed.In order to investigate the ability of adapting different concentration of acids and temperature,batch experiments with different concentrations of acetate and propionate were carried out at both mesophilic and thermophilic conditions.Modified Gompertz model and first order model were used to analyze the methane production kinetics.The inoculum was got from coffee mate anaerobic digestion,because coffee mate contains 2%protein,34%fat and 56%carbohydrates,which can simulate the real ingredients in anaerobic fermentation.The concentrations of acetate acid were set for 0,2 000,5 000,10 000 and 20 000 mg/L;and the concentrations of propionate were set for 0,500,1 000,2 000,4 000 and 8 000 mg/L.In addition,sodium hydroxide was used to adjust the pH value in a range of 7.2-7.6 in every batch bottle,and every concentration had 3 parallels to ensure the veracity of this experiment.The result showed that both of acetate and propionate degradation faster at the lower concentration.Acetate was easily degraded at mesophilic condition,when the concentration of acetate was 5 000 mg/L;mesophilic reactors had the maximum methane production rate which was 101 mL/d,while the thermophilic reactor had the maximum methane production rate which was 77 mL/d when the acetate concentration was 10 000 mg/L.With the acid concentration increasing,methane production rate decreased and the thermophilic reactor had a higher tolerance for the acetate concentration.In contrast,propionate was easily decomposed under the thermophilic condition and the lag phase under mesophilic was greatly affected by the acid concentration;when the propionate concentration increased fro

关 键 词：甲烷 动力学 温度 厌氧发酵 乙酸 丙酸 

分 类 号：X712[环境科学与工程—环境工程]