Anaerobic Digestion Of Molasses Alcohol Wastewater And Culture-independent Study Of The Microbial Communities In The Reactors

Molasses alcohol wastewater is a kind of high solids, high concentration, high acidity dark brown organic wastewater with high COD content, which is one of the major sources of pollution of the sugar-refinery.The most appropriate method of molasses alcohol wastewater treatment is anaerobic digestion, which is also a process of methane fermentation. Investigation the nicrobial community diversity through metagenomic sequencing and molecular ecology approaches, provid a basis for regulation of molasses alcohol wastewater treatment using functional microorganisms.The simulators for co-digestion of pig manure and molasses alcohol wastewater as the raw material were established under laboratory conditions,with the fermentation volume was4L, and the ratio of raw materials for H1～H4fermentation tank for pig manure against molasses of alcohol wastewater (w/v) was:1:0;1:0.5;1:1;1:1.5, three repetitions were involved for every treatment, with the fermentation temperature of37℃, the fermentation pH ranges from6.4to6.7. Physical and chemical properties of reactors during fermentation and gas production were detected and analyzed, it was found that TC, TS, VS, C/N ratio declined, but TN content remained essentially unchanged,and the COD removal rate was68.7%,60.9%,56.4%and54.0%respectively.Metagenomic and DGGE were used to analyze the diversity of the bacterial before and after fermentation, the results showed that the structure and diversity of bacterial communities before and after the fermentation is very different. At the beginning of fermentation, macromolecules degrade into small molecules, some bacteria such as Ruminococcaceae. Lachnospiraceae. Propionibacteriaceae were dominant organisms, and Prevotellaceae made the greatest contribution in the species which caused sample differenties. At the late fermentation, hydrogenetic microorganisms (mainly the presence of methanogenic bacteria), which can utilize hydrogen, carbon dioxide, acetic acid and other small molecules in order to production methane, so the Syntrophomonadecea holded a great proportion. Samples of pre-fermentation and post-fermentation after cluster analysis found that the differences of strains similar is relatively large, but in certain regional context.In order to better understand of molasses of alcohol wastewater anaerobic biotreatment. Microbial diversity in anaerobic bioreactors treating molasses alcohol wastewater under industrial scale. Compared with no added molasses alcohol wastewater. Fermentation with molasses alcohol wastewater which ran two months, we found that the number of microorganisms has doubled, there were also a lot of Bacteroidaceae, Enterobacteriaceae, Lactobacillaceae, and Propionibacteriaceae, while both the proportion of bacterial distribution were quite different, but the Syntrophomonadaceae decreased from28.7%to38.6%, Maybe these bacteria Branchs play a crucial role in the molasses alcohol wastewater treatment process.