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以两种厌氧污泥和一种绵羊胃液 (rumen)的混合物为接种物 ,对葡萄糖进行厌氧发酵。通过调节通气和搅拌控制发酵系统的氧化还原电位 ,考察了恒化器中氧化还原电位对葡萄糖厌氧发酵产物生成的影响。结果表明 ,氧化还原电位对发酵产物有强烈影响。在pH 6和水力停留时间 5h及 10h时 ,在Eh - 550～ - 30 0mV ,乙酸和乳酸是主要产物 ,丁酸浓度随Eh的升高而降低 ,而丙酸和甲酸浓度随Eh升高而增加。当Eh >- 2 0 0mV ,除乙醇外的所有产物浓度都急剧下降 ,而此时的电子回收率极低 ,约为 4 0 %。在Eh >- 10 0mV ,pH <3 5的条件下 ,酵母是主要微生物 ,而乙醇是主要产物 ;高的氧化还原电位有利于酵母的生长 ,而低的氧化还原电位有利于乙醇的形成。
Anaerobic fermentation of glucose was performed with a mixture of two anaerobic sludge and a sheep rumen. By adjusting the aeration and stirring to control the redox potential of the fermentation system, the effect of the redox potential of the chemostat on the production of glucose anaerobic fermentation products was investigated. The results show that the redox potential has a strong effect on the fermentation product. At pH 6 and HRT 5h and 10h, acetic acid and lactic acid were the main products at Eh - 550 ~ - 30OmV. Butyric acid concentration decreased with the increase of Eh, while propionic acid and formic acid concentration increased with Eh increase. When Eh> -200 mV, all the concentrations of all the products except ethanol dropped sharply, but the electron recovery was very low at this time, about 40%. Under the conditions of Eh> -10OmV and pH <35, yeast is the main microorganism, while ethanol is the main product. High redox potential is favorable for the growth of yeast, while low redox potential contributes to the formation of ethanol.