| In recent years,with the rapid development of the economy,people's material and living levels have been raised,and the food waste is increasing and has caused great influence on environment.The starch in the food waste is a polysaccharide structure,which can be used by microorganisms to decompose themintoraw sugars and turn them into fue l ethanol further.The food waste contains a large amount of cellulose,which is difficult to break down,so the rapid and efficient degradation of cellulose is the key to increasing the yield of fuel ethanol.This research managed to domesticate microorganisms which could degrade the cellulose efficiently from the marine(ocean,wetland).Through the salt-tolerant domestication,the cellulose decomposition bacteria could adapt to the high-salt environment of food wasteand decompose cellulose into raw sugar.On this basis,this study explored the simultaneous fermentation bybacteria cellulose decomposition microbes andethanol synchronization,and in order to use the synergistic effect of them to convert the food waste into fuel ethanol quickiy and improve the ethanol production rate.The research results had extended the application of salt-resistant cellulose bacteria,and provide a new idea for the resource utilization technology of food waste disposal.The main results of this experiment were as follows:(1)Five groups of ellulose decomposition bacteria,which all had material function and structural stability,were selected from the marine and wetlands through the selective medium technology.The numbers were H+SCNB,HN,HS,SN,BC.Comparing with the four groups of cellulose decomposing bacteria in the laboratory,the three best groups of them were screened,and the numbers were H+SCNB,85,G1.The cellulase activity of them was 2.98 U/m L,2.96 U/m L,3.40 U/m L,all of which could degrade the filter paper in salt content of 2%(w/v)medium.(2)In the course fermentation process of food waste,the co-culture of microbes was determined to add ethanol bacteria in the food waste to ferment for 24 h at first,and then added salt-tolerant cellulose decomposition bacteria.The content of ethanol in the food waste of the bacteria group H+SCNB,85,G1 and ethanol was 2.48%(v/v),2.52%(v/v)and2.50%(v/v)and other fermentation methods will inhibit the production of ethanol.(3)Under the conditions of sterilization,non-sterilization and 160?to measure food waste composition,the results showed that the p H value showed a regular increase from high to low,and the change of p H indicated that the acid was fermented before fermentation and then converted to ethanol.The content of xylose increased first and then decreased,indicating that hemicellulose was degraded to produce xylose,and then xylose was ethanol.And the content of total phosphorus was increased first and then decreased.The release of phosphorus content in the fermentation resulted in the release of phosphorus content,and the decrease of phosphorus content was caused by the absorption and utilization of microorganisms.The total nitrogen content was decreasing and the protein content was decreased.Decreasing the trend,indicating that nitrogen is used by microorganisms;calcium ion content decreased first and then increased the trend of decreasing;the sterilized glucose content was increased first and then reduce the trend.The amount of glucose that was not sterilized and treated at 160°C was drastically reduced and increased,and glucose was converted to ethanol,after which the microorganisms converted some substances to glucose.The content of SCOD in sterilization and non-sterilization treatment increased first and then decreased.After microbial action,it was difficult to degrade the material into degradable small molecule,which resulted in the increase of SCOD,and then the conversion of small molecule into liquid,resulting in SCOD the reduction.The SCOD content at 160°C was reduced-increased-decreased-increased-decreased wavy trend. |
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