Zhao Tiantao, Zhang Lijie, Chen Haoquan, Zhao Youcai
Department of Chemical and Biological Engineering, Chongqing University of Technology, Chongqing 400050, China.
J Environ Sci (China). 2009;21(6):827-33. doi: 10.1016/s1001-0742(08)62348-7.
The inhibition effects and mechanisms of chlorinated methane and acetylene on methanogenesis in the anaerobic digestion process of the biodegradable wastes were investigated. It was found that both chloroform and acetylene could effectively inhibit methanogens while the biodegradability of the wastes was not affected. Acetylene inhibited the activity of methanogens, while chloroform inhibited metabolic process of methanogenesis. A central composite design (CCD) and response surface regression analysis (RSREG) were employed to determine the optimum conditions and interaction effects of chloroform and acetylene in terms of inhibition efficiency, production of volatile fatty acids (VAF) and molar ratio of propionic acid to acetic acid. Chloroform had significant effect on enhancing the production of VFA (F = 121.3; p < 0.01), and acetylene promoted the inhibition efficiency (F = 99.15; p < 0.05) more effectively than chloroform (F = 9.72; p > 0.05). In addition, a maximum molar ratio of propionic acid to acetic acid of 1.208 was estimated under the optimum conditions of chloroform concentration of 9.05 mg/kg and acetylene concentration of 3.6x10(-3) (V/V). Hence, methanogens in the wastes can be inhibited while the stabilization process of the biodegradable wastes can still work well, as propionic acid generated during the inhibition process could hardly be utilized by methanogens.
研究了氯代甲烷和乙炔对可生物降解废物厌氧消化过程中甲烷生成的抑制作用及其机制。结果发现，氯仿和乙炔均可有效抑制产甲烷菌，同时不影响废物的生物降解性。乙炔抑制产甲烷菌的活性，而氯仿抑制甲烷生成的代谢过程。采用中心复合设计（CCD）和响应面回归分析（RSREG）来确定氯仿和乙炔在抑制效率、挥发性脂肪酸（VAF）产量以及丙酸与乙酸摩尔比方面的最佳条件和相互作用效应。氯仿对提高VFA产量有显著影响（F = 121.3；p < 0.01），且乙炔比氯仿更有效地促进抑制效率（F = 99.15；p < 0.05，氯仿F = 9.72；p > 0.05）。此外，在氯仿浓度为9.05 mg/kg和乙炔浓度为3.6×10⁻³（V/V）的最佳条件下，估计丙酸与乙酸的最大摩尔比为1.208。因此，废物中的产甲烷菌可被抑制，而可生物降解废物的稳定化过程仍能良好运行，因为抑制过程中产生的丙酸几乎不能被产甲烷菌利用。
