SET Proceedings 2978-4387 Caravel Press 10.65582/set.2010.124 2010.124 Temperature Variation in Biogas Digester heated by Ground-source Heat Pump intermittently PeiXiaomei ShiHuixian huixian_shi@tongji.edu.cn LiYongming WangTao RongLing ZhangDi College of Mechanical Engineering, Tongji University, Shanghai, China Modern Agricultural Science & Engineering Institute,Tongji University, Shanghai, China 24082010 9 978-1-995850-04-7 1 7 24 August 2010 © 2010 Copyright WSSET 2010

The temperature variation will directly affect the gas yield and its rates of the entire process of biogas engineering. By arranging the temperature probes into the biogas digester, the temperature variation of a mesophilic fermentation biogas digester heated by ground-source heat pump system system intermittently has been obtained and analysized. The results show that, in noheating condition, the average temperature in biogas digester decreases slowly. The temperature decreases 0.054 ℃ / h and the gas production rate is 0.49 m³ / (m³ • d). In the heating condition, the temperature is uniform and stable in the middle and lower area of the digester, uneven and instable in the upper area, while the temperature is higher in the middle and lower area than the upper area; in heating process, the average temperature rise about 0.3 ℃ / h. The results also show that the location of coil heating and stirring have a great impact on the temperature variation. The experimental results could be refered by constructing heat and mass transfer mathematical model about the flow field of the digester and for the system design or economic operation.

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