Study on local temperature controlling technology and equipment in heat disaster coal well

Along with the continuous increase of coal resource mining depth, high temperature and heat disaster is becoming more and more serious. The health of workers under coal wells can be threatened at any time and the safe mining of coal resources is seriously impacted. In order to eliminate coal well heat disasters, scholars at home and abroad have inputted a lot of time and energy. They have researched the controlling theory of coal well heat disasters. They developed cooling equipment for high temperatures and have achieved some results. However, the equipment is too large and as a result it is hard to move. The power of the equipment is high so it costs a large amount of electric power. Maintenance costs are huge, and therefore the application of this technology is not ideal. Based on this, the present study firstly analyzed the influence factors of coal well heat disaster. Then, the calculation method of cooling load in coal wells was researched. The authors put forward the technology for controlling local high temperatures. The ZLS-90 movable cooling equipment was developed successfully which includes a refrigeration compressor, evaporator, water cooling condenser, and expansion valve. The property of the compressor plays an important part in the cooling effect of the whole system. After comparing, the GEA bock compressor was chosen. The enthalpy difference comprehensive testing system was used to test the performance of the equipment. Test results showed that all performance indexes comply with the design requirements. The property is also stable. This paper also proposes discharging heat with a heat-rod to deal with the heat of condensation as well as using the heat synthetically. Effective cooling can be carried out by means of local temperature controlling technology and equipment. In that case, the working environment under coal wells would be guaranteed and the safe production of coal wells would be guaranteed. It would realize efficiency, conservation, and the environmental protection of resources.