Research On The Application Of Thermal Hazard Prevention Technology In The Face Of Yangchangwan Coal Mine

In recent years,the main mining activities of the Yangchangwan Coal Mine have expanded to the depths.Affected by the ground temperature,the heat release of coal and rock formation,and the heating of equipment operation,underground thermal hazards have become the main factors affecting the safety of mine production.The underground high temperature locations mainly occur in the mining working faces.According to the actual measured data,the working face temperature during the initial mining period is between 28 and 31°C.From August to October,the maximum temperature of the return air flow reaches35°C and the relative humidity exceeds 95%.The mining depth is generally proportional to the severity of thermal damage.Non-artificial cooling methods such as optimizing the ventilation system or increasing the air volume have been unable to solve the problem of heat damage on the working face.Therefore,it is worthy of our study to adopt new economical and feasible artificial cooling measures to achieve the purpose of cooling,and to provide employees with a safe and comfortable working environment.This paper is based on the mining practice of 130205 working face of the author's work unit,through theoretical analysis,establishment of mathematical models,data calculation,collection of field data and other comprehensive research methods,the application of thermal hazard prevention technology in the process of coal mining face is carried out more in-depth Research.This study is mainly based on the measured data of the temperature changes in the various mining roadways in the deep coal seam of the Yangchangwan Coal Mine.Through the calculation of the heat source heat dissipation,it is proposed that the main factors causing the high temperature in the mine are the heat dissipation of electromechanical equipment and the heat dissipation of oxidation.Using the law of conservation of energy,a mathematical model is established based on the cooling target temperature and humidity,and a new cooling load calculation idea is proposed.Through the technical and economic comparison of the main cooling methods currently used in China,and the field application and existing problems of the water source heat pump local cooling system and the liquid nitrogen cooling system that have been used in the Yangchangwan Coal Mine,the selection of the prevention and control of heat damage in the coal mining face is discussed.The applicability and economy of the mobile local refrigeration system.According to the cooling load demand,the main unit and pipeline selection parameters were calculated in detail,and the cooling effect was verified on site.Finally,the cooling effect verified the accuracy of the new cooling load calculation method and the rationality of the cooling scheme selection and design.After the implementation of the system,the average temperature of the lower mouth of the coal mining face was reduced from 27?28? before cooling to 24?25?,the cooling range was 3?4?,and the humidity was reduced from 78?85% before cooling to 56?66%.,The reduction rate is 19?22%;the average temperature of the working surface drops from31?32? before cooling to about 29-30?,the average cooling range is 2?3?,and the humidity is reduced from 94%?97% before cooling.It is 75%?80%,and the reduction rate is17?19%,which effectively solves the problem of high temperature and heat damage that restricts the safe production of coal mining faces,and greatly improves the working environment of personnel.The results of this study can provide scientific and reference experience for the treatment of thermal hazards in deep-buried working faces under similar conditions in the Ningdong mining area.