糟液循环对开放式餐厨垃圾乙醇发酵的影响及工艺改进

在前人研究的基础上对餐厨垃圾乙醇发酵糟液进行多次循环使用,以减少废液的排放量.重点考察了糟液循环对餐厨垃圾产乙醇的影响.结果表明:当未经处理的乙醇糟液在全回流条件下,对乙醇发酵产生明显抑制,全循环4次后乙醇产量由28.4g/L 降至2.56g/L.随着循环利用次数的增加,乳酸、SS、DS和盐分均产生积累,分别达5.45、64.7、99.5和12.3g/L.为提高糟液循环次数,本研究采用2/3的糟液回流和絮凝处理后全回流的方式,其糟液循环利用7次后,前者乙醇产生量维持在25.5~35.5g/L,而后者的乙醇产量在12.2~32.4g/L.糟液2/3回流循环效果要优于絮凝处理后全回流的方式,今后需考虑两者相结合进行糟液循环的方式.

Effects of distillery waste recycling on open ethanol fermentation from kitchen garbage and technological enhancement

Based on the previous studies, in order to reduce the distillery waste form ethanol fermentation, the distillery wastewater of ethanol production from kitchen garbage was recycled in this study. Particularly, the accumulation of the by-product during the fermentation and their effects were investigated. The results indicated that ethanol fermentation was inhibited obviously by full-recycling distillery wastewater without treatment. After 4times full-recycling, ethanol production was decreased from 28.4g/L to 2.56g/L. With the increasing recycling times, lactic acid, SS, DS and salinity were accumulated to 5.45, 64.7, 99.5 and 12.3g/L, respectively. In order to improve the recycle times, 2/3 partial-recycling mode and flocculation full-recycling mode were utilized. During 7times of distillery wastewater recycling, the ethanol productions maintained at the range of 25.5~35.5g/L for 2/3partial-recycling mode. While for flocculation full-recycling mode, the ethanol production maintained at the range of 12.2~32.4g/L. 2/3partial-recycling mode was superior to flocculation full-recycling mode. In future, the combination of the two recycling methods should be considered for further improving the distillery wastewater recycling system.