Thermal Recovery and Utilization of Coal Gangue Mountain Based on Semiconductor Thermoelectric Technology

Abstract

Large-scale spontaneous combustion often occurs in coal gangue hills, resulting in a large amount of heat waste. This paper provides a solution: using the gravity heat pipe heat transfer technology to extract the heat energy in the high temperature area, and according to the thermoelectric power generation technology to convert heat energy into electrical energy to transport to electrical equipment, to achieve the purpose of energy recovery and utilization. In this paper, the ANSYS Workbench software is used to model and analyze the thermoelectric generator, and it is found that the temperature difference is an important factor affecting the overall output power of the device. In order to improve the output power of the device, the experimental platform was built to simulate the spontaneous combustion heating process of coal gangue, and the optimization was carried out from three aspects: the arrangement interval of heat pipe, the setting of cooling water flow and the number of thermoelectric generators in series. The experimental results show that when a heat pipe is arranged at intervals of15 cm and the cooling water flow is set to 2.1 kg/min, the temperature difference between the two ends of the thermoelectric generator can be maintained to the maximum. After optimization, when the temperature difference between the cold and hot ends of the thermoelectric generator is maintained at 200°C, the maximum output power of the thermoelectric generator can reach 35 W. It can be verified that the device has practical value and broad development space.