摘要
为明晰厌氧消化过程的主要限速步骤,分别以丁酸、乙酸、H_2/CO_2为基质,在37℃和pH 5.00-9.00条件下对厌氧活性污泥进行培养,依据Shelford耐受定律对食丁酸产氢产乙酸菌（SBOB）、乙酸营养型产甲烷菌（ACM）和氢营养型产甲烷菌（HTM）的pH值生态幅及基质转化速率进行分析.结果表明,SBOB、ACM和HTM的pH值生态幅分别为6.19-8.59、5.50-7.74和4.39-9.23,其代谢最适pH值分别为7.39、6.62和6.81.在最适pH值条件下,厌氧活性污泥对丁酸、乙酸、H_2/CO_2的转化速率分别为0.86、1.04和1.09g CODequ/（g MLVSS·d）.可见,与产甲烷菌相比,产氢产乙酸菌的pH值生态幅更窄,基质转化速率更慢,对厌氧消化过程具有更为显著的限制作用.
To identify the rate-limiting degree of hydrogen-producing acetogenesis and methanogenesis in anaerobic digestion, anaerobic activated sludge sampled from an UASB was cultivated at 37℃ with a series of initial pH ranged from 5.00 to 9.00. With butyric acid, acetic acid and H_2/CO_2 as substrate, respectively, the ecological amplitude of pH and the substrate conversion rate of syntrophic butyrate-oxidizing bacteria（SBOB）, aceticlastic methanogens（ACM） and hydrogenotrophic methanogens（HTM） were evaluated according to the Shelford＇s tolerance law. The results showed that the ecological amplitudes of pH for SBOB, ACM and HTM were 6.19-8.59、5.50-7.74 and 4.39-9.23, with an optimal pH of 7.39, 6.62 and 6.81 for their metabolism, respectively. With the optimal metabolic pH, the specific conversion rate of butyric acid, acetic acid and H_2/CO_2 by the sludge was 0.86, 1.04 and 1.09 g CODequ/（g MLVSS·d）, respectively. Obviously, the hydrogen-producing acetogens had narrower pH ecological amplitude and lower substrate conversion rate than the methanogens, indicating that hydrogen-producing acetogenesis in the anaerobic activated sludge had a stronger limitation on the anaerobic digestion.
出处
《中国环境科学》
EI
CAS
CSCD
北大核心
2016年第10期2997-3002,共6页
China Environmental Science
基金
国家自然科学基金资助项目(51478141)
城市水资源与水环境国家重点实验室(哈尔滨工业大学)自主课题(2016DX06)
关键词
厌氧消化
限速步骤
PH值
生态幅
基质转化速率
anaerobic digestion
rate-limiting
pH
ecological amplitude
substrate convertion rate
