Study On The Factors Affecting The Odd/even Number Regularity Of VFAs Produced By Food Waste And PHAs Accumulation In Fermentation

Food Waste?FW?has not been fully effective used and disposed by some of the traditional processing mode,it not only brings no effective use of resources,and remains other harmful substances caused environmental pollution after treatment,the consequences can not be ignored.How to utilize resource and deal with FW lead people to pay more and more attention,the resource utilization of FW can not only effectively solve the cost problem of garbage disposal,but also can produce useful energy and resources on the basis of low cost,which realizes the recycling of waste and continuous production of renewable energy,it has important significance to the sustainable development of economy and society.The purpose of this project is to combine FW disposal and sewage treatment technology,it can solve the problem of resource utilization of FW and utilization of sewage carbon source.Aiming to FW,four kinds of organic FW are choosed representatively,without the control,changes of odd and even VFAs and characteristics of FW are vestigated in fermentation process,from which can be choosed substrate respect of even/odd number VFAs obviously.On this basis,paying attention to the study of single factor and orthogonal combination,exploring further the trend of changes in odd/even number and composition of VFAs in the fementation of FW,then,the different odd/even number proportion of VFAs are determined,it can use as a carbon source to explore the regularity of PHAs;Phosphorate Accumulation Organics?PAOs?with sodium acetate as the sole carbon source set as a blank group,and the different odd/even numbered proportion of artificial resouces as the same as femented broth set as a control group,which observating the changes of PHAs in sewage sludge.The experimental results showed that in the four kinds of FW,rice wash can produce odd fatty acids as well produce even number fatty acids.In the single factor,the optimal pH is 6 to10,the optimum temperature is 25?to 45?,the best fermentation in 5 to 9 days.in the orthogonal combination,when the temperature?T?is=35?,pH=8,the ratio of odd/even numbered VFAs is 1:1 at 7^th;T=25 C,pH=8 is 1:2 at 9^th;T=45;C,pH=6 is 1:3 at 7^th.Adding three kinds of fermented broth to the sludge,artificial resource and fermented broth compared to the sludge,PHAs content increased significantly,when the odd/even number proportion VFAs is 1:1,PHAs accumulation are the highest?80.69mg/L?;fermented broth is more conducive to PHAs t than he artificial resouces.In anaerobic stage,the mass fraction of PHB increased significantly,and the mass fraction of PHV increased significantly too.Therefore,different odd/even proportion of VFAs could control PHAs in a directional way.Adding Small amount of oxygen and changing the type of bacteria,the composition of PHAs would be changed.