| There were about 90 million tons food waste produced in China every year.Food waste is apt to contaminate the environment due to high moisture and high organic content.At the same time,there is a great potential of food waste recycling.Compared with traditional food waste treatment technology,using food waste processing equipment produce organic fertilize at 60 ? can reduce the secondary pollution caused by waste collection and transportation.But the low processing efficiency and odor pollution problems still not be solved.Therefore,this project hopes to improve composting efficiency and organic fertilizer quality by preparing highly effective microbial agents.We also try to use deodorant microbial agents to solve the odor pollution problem.To prepare a microbial agent for food waste degradation,the biodegradation potential of different strains was evaluated.Then the microbial agent has been applied to food waste disposal equipment.We also prepared a deodorization microbial agents to solve the odor problem,the main conclusions are as following:(1)24 strains were isolated and purified in the process,mainly of these are bacillus sp.,citrobacter sp.,and lactobacillus.After strains screening,10 selected strains were combined as the food-waste degradation microbial agents.The microbial agent degradation ratio for starch,protein,fat and cellulose were 94.39%,95.03%,56.44%and 51%respectively.(2)During the strain drying process,the optimal protectant concentration was trehalose 1%,skim milk powder 1%,soluble starch 1%,glycerol 0.5%,being storaged at room temperature for 150 days,the amount of living bacterium has reduced 27.4%.(3)When inoculated the food waste degradation microbial agents,the pH of food waste was dropped from 6.62 to 6.54,the EC was changed from 2.36 to 2.43,the C/N was dropped from 19.54 to 13.7,after 48 h,the total amount of colonies was 1×109 CFU/g,and the seed germination ratio was 90.1%,total humic acid content was 3.1%,compared with control,the total solid weight loss of food waste was increased by 50.5%.(4)The results of microbial community distribution show that,after inoculating the microbial agents,the proportion of bacillus was rose from 0.02%to 23.94%,the proportion of citrobacter was rose from 0%to 13.97%,the Chao index and Shannon index for microbial diversity was higher than control 14.13 and 1.19 respectively.(5)In this thesis,the optimum condition for biological deodorization was 37 ?,pH=7.0,inoculated amount was 2.0%and deodorization time of 12 h;under the optimum condition,the ammonia and hydrogen sulfide degradation ratio of deodorization microorganisms was 81.6%and 87.3%;the self-made deodorization microbial agent got the hightest ammonia degradation ratio when compared with kangpai microbial agents and a chemical deodorant,and the hydrogen sulfide degradation ratio of self-made deodorization microbial agent was 11.6%higher than kangpai microbial agents,but 6.4%lower than chemical deodorant.(6)The odor intensity was decreased by 1-2 level after spraying self-made deodorization microbial agent at Miyun landfill.At Nangong waste composting plant,after spraying microbial agents,the ammonia concentration of fermentation case was declined by 72.34%,TVOC concentration declined by 83.33%,the concentration of hydrogen sulfide was reduced to 0.1 ppm,and the odor intensity was dropped from level 5 to level 3. |
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