污泥厌氧消化过程中产氢产乙酸/同型产乙酸协同产酸研究

Synergistic Effect of Syntrophic Acetogenesis and Homoacetogenesis for Volatile Fatty Acids Production from Sludge by Anaerobic Digestion

应用产甲烷菌抑制剂溴乙烷磺酸盐(BES)阻断产甲烷过程,并添加丁酸盐以强化产氢产乙酸过程,研究不同条件下乙酸和气体的累积,借助于热力学分析推断污泥产酸发酵过程中的乙酸累积机制.结果表明,在抑制产甲烷体系中,反应吉布斯自由能降低至临界值(-15 kJ.mol-1)时,乙酸累积浓度达6 g/L,协同作用中产氢产乙酸菌与同型产乙酸菌产生乙酸的比例为7∶3;在H2分压为3.2 kPa,4 g/L的丁酸和6 g/L的乙酸体系中,产氢产乙酸和同型产乙酸的协同作用不再发生.同型乙酸菌和产氢产乙酸菌可利用协同作用产生乙酸,但产氢产乙酸菌与同型产乙酸菌的互营关系是有限的.

By using metabolic inhibitor（BES） to block the methanogenesis and adding butyrate to enhance syntrophic acetogensis,syntrophic acetogens/homoacetogens synergism during the acidification fermentation of sludge from anaerobic digestion was investigated and then the acetate accumulation mechanism was clarified.The results indicated that the acetate concentration was 6 g·L-1 in the condition of the ΔG was about-15 kJ·mol-1 and no methanogens,and the proportion of acetate were produced by syntrophic acetogens and homoacetogens is 7∶3.However,the syntrophic acetogens/homoacetogens synergism did not occur under the condition of H2 pressure was 3.2 kPa,the butyrate concentration was 4 g·L-1 and the acetate concentration was 6 g·L-1.The acetate can be produced by the syntrophic acetogens/homoacetogens synergism but it is restricted.