Anaerobic Digestion Of Kitchen Waste And Sludge

Nowdays, kitchen waste and municipal sludge were main pollution of solid waste in China. This paper had a research on anaerobic digestion of kitchen waste and sludge. Firstly, gas production, gas composition, degradation efficiency and pH were measured to conduct the effect of different dosage of kitchen waste on anaerobic digestion system. Furthermore, different HRT and temperature were performed to find the optimal anaerobic digestion conditions.The highest volume of gas production was collected at136.24L,when the conditions of anaerobic digestion was at mix ratio of50:50,10%solid content and medium temperature of anaerobic digestion. At the same time, the content of CH4in total biogas was highest and degradation efficiency was obtained at66.82%. The pH in anaerobic digestion system was controlled at4.4-7.8. Compared with signal anaerobic digestion, the gas production and degradation efficiency had a high improvement on co-digestion system, and the system was more stability.With the improvement of digestion temperature, the cycle of gas production was shorter. It was considerable of the gas production on room temperature and medium temperature of anaerobic digestion. The removal rate of COD and VS were higher with the extention of the HRT. When the HRT was maintained at25days, the COD and VS were highest.According to the research, it is supposed that the best condition of anaerobic digestion in actual engineering was:1) the mix ratio of kitchen waste and municipal sludge was1:1;2) the temperature of anaerobic digestion was35℃;3) the HRT was16-25days.