Research On Effective Microorganism Agent For Degradation Of Food Wastes

Food wastes are kitchen leftover and hogwash generated in kitchen and eatery, and also rare organic nourishments. The food wastes are large in amount, dispersed, decayed easily, stinks. If these did not be treated in time, it will pollute road, atmosphere and river system. Chemical composition of the food wastes were starch, protein, fat and cellulose.And the composition could be degraded by microorganism agent. And the products of degradation of food wastes could be used on agriculture. So how to treatment the food wastes innocuously, reducing and recycling would be the important thing at present society.Supported by Social and Technology Develop Program of Changchun (Research on Microbial Degradation of Food Wastes, project serial number: 05SF11). The thesis degraded food wastes by using biological degradation method. It not only can avoid polluting environment, but also can decrease the disposal quantity and cost of MSW, and also supply science foundation of the research of the process and equipment of microbial degradation of food wastes.The experimental research and productions has been expatiated as follows:(1) Making use of kinds of the corresponding culture mediums to screen strains on basis of collecting the sample of food wastes and Effective Microorganism agent. The strains had been that gained, which had the ability to degrade starch, protein, fat, cellulose.1) 109 strains had been isolated, and in these strains, 28 strains belong to bacteria, 30 strains belong to mould, 25 strains belong to yeast, 26 strains belong to actinomycetes.2) According to the characteristics of enzyme production, the strains had been screened, which had the ability to degrade starch, protein, fat, cellulose.A. The strains had been screened, which had ability to degrade starch. 3 strains belong to bacteria; 12 strains belong to mould; 2 strains belong to yeast.B. The strains had been screened, which had ability to degrade protein. 1 strain belongs to bacteria; 12 strains belong to mould; 2 strains belong to actinomycetes.C. The strains had been screened, which had ability to degrade fat. 12 strains belong to bacteria; 2 strains belong to mould; 1 strain belongs to yeast. D. The strains had been screened, which had ability to degrade cellulose. 12 strains belong to mould; 2 strains belong to yeast; 1 strain belongs to actinomycetes.(2) Research on effective microorganism agent which can degrade food wastes efficiently.1) The effective microorganism agent had been constructed by orthogonal test. The compound microbial strains contain the effective microorganism agent for degradation of starch, the effective microorganism agent for degradation of protein, the effective microorganism agent for degradation of fat and the effective microorganism agent for degradation of cellulose. These 4 compositions contain 6 bacteria strains, 11 mould strains, 2 yeast strains, 1 actinomycetes strain.2) According to growth curve of the strains, the best inoculated time had been confirmed. The inocula had been prepared. There was one strain which had the ability to degrade food wastes in inocula.3) According to the ratio of the inocula was 1:1, the effective microorganism agent had been prepared. And the effective microorganism agent had been prepared, according to the ratio of starch, protein, fat, cellulose in the food wastes, namely 1:2.4:1.4:1.(3) The strains had been identified. The identification results about 6 bacteria strains and they belong to cellulomonas, pseudomonas, bacillus, lactobacillus.The identification results about 2 mould strains and they belong to aspergillus, trichoderma.The identification results about 1 actinomycetes strains and it belong to micromonospora.(4) The process parameters had been optimized in the process for degradation of food wastes.1) Through the single factor test, the thesis researched the influence of the main four factors to the degradation of organic matter of food wastes.It was found that the degradation increasingly along with the reaction temperature, initial moisture, inoculums and C/N. But when it reached the highest degradation, the degradation increased slowly along with factors. And the degradation had significant curve relation to reaction temperature, initial moisture, inoculums and C/N. So the regression model was created between degradation and the four factors.2) Arrange quadratic general rotary unitized design near the best parameter which was fixed by single factor test, and establish the mathematics model. It was found that four factor was important factors for the degradation by analysis the mathematics model. But the reaction temperature was no important for the degradation.So chose the optimum reaction temperature by single factor test, it was 40℃3) It was found that the four factors could be obtained the higher degradation at the optimum value range by analysis the mathematics model. It was considered the process conditions of aerobic microbial degradation, so the best combination parameter was fixed exactly: reaction temperature 40℃, initial containing moisture 55%, inoculums 8%, C/N 35:1. And in this condition, the maximal degradation of organic matter was 78.5%. And it was close to theoretical value 78.8%. It showed that the mathematics model was suitable for degradation of food waste.(5) It was founded that added effective microorganism agent could improve the degradation by the contrast test. And in the process for degradation of food wastes, the duration had no different between EM and effective microorganism agent that making by laboratory.Research on the effective microorganism agent for degradation of food wastes, it was found that add the microorganism agent to the process conditions of the aerobic microbial degradation could improve the degradation.But we had not know the complex relationship between the strains of the effective microorganism agent. And we would research the complex relationship between the strains of the effective microorganism agent. In this way, the production of the effective microorganism agent would be achieved quickly. And it could provide the technical support for treatment equipment of food wastes.