Research On Coal Spontaneous Combustion Prediction Of High Gas Coal Seam In Wei Jiadi Fully Mechanized Caving Face Goaf

As we all know, China is rich in coal resources and its coal production and consumption rank keep high in the world. However, the phenomenon of coal spontaneous combustion is quite serious, which not only constraints the safety in production and development of mine with high yield and efficiency, but also cause waste of resources, environmental pollution, personnel and property losses. Wei Jiadi is a coal mine with high gas-containing and is liable to spontaneous combustion. As a result of being too thick of partial coal seam, the coal may be left much in the mined-out area. It is easy to make for spontaneous combustion. Especially different levels of seam will leak wind while mining group of high gas-containing coals, which would make coal spontaneous combustion more serious and then regularity of spontaneous combustion becomes more complicated.In this thesis, it first carried out spontaneous combustion experiments of Wei Jiadi coal seam and worked out the characteristic parameters under similar condition of that on spot, such as temperature raising rate, rate of oxygen consumption, CO and CO2 production rate, heat emitting intensity, characteristic temperature as well as the spontaneous combustion period. Based on above experiments, it set an index system of forecasting the spontaneous combustion of coal. Second, by observation and analysis of combusting plot in Wei Jiadi coal mine1308 fully mechanized caving face goaf, it got the thickness of float coal and distribution rules of the oxygen and methane in the two sides of intake air and return air. Thirdly, it established physical and mathematical models of the flow and concentration field with definite conditions. Next, by using Fluent software to do numerical simulation on the air leakage condition in the 1308 fully mechanized caving face goaf and as a result, the distribution rules of oxygen concentration and flow velocity were drew out in the fully mechanized caving face goaf. Then, based on numerical simulation results and observation data on spot, it divided the mined-out goaf into"three zones"and set down the basic distribution law of the"three zones", the risk part of the spontaneous combustion in mined-out goaf, as well as the limitation promoting speed and made early prediction technology of spontaneous combustion in goaf better. Finally, according to the results of the prediction, the comprehensive technical scheme to prevent coal fire which was suitable for fact of Wei Jiadi coal mine high gas-containing seam was put up. By implement of this scheme, the occurrence of spontaneous combustion could be effectively prevented and controlled.