Study On Spontaneous Combustion And Explosion Characteristic And Prevention And Control Technology With High-gas And Easily-spontaneous Combustion Coal Seam In Stope

Seepage flow mechanics, heat and mass transfer theory and so on are used in the research. The effects of temperature, pressure and gas on the density of mixed gas are studied. Based on Boussinesq's Approximation, the introduction of porosity factor, and k -εturbulent model, the closure of turbulent equations is realized. Trough the combination of the non-linear seepage flow equations and the diffusion equations and the N - S equations, a general model is established. This model may be used to solve the velocity field, the pressure field, the temperature field and the concentration field for the mixed flow of the turbulent flow, transitional flow and laminar flow in stope.The photographic method and the computer imagery processing technology are used. The characteristics of porosity distribution in goaf are studied. For the fist time, the characteristic of dustpan-typed porosity distribution is obtained.Based on the experiment, the carbonification method is used to complete the heat and heavy analysis. A three-stage-division method for the heat and heavy curve of spontaneous coal combustion, namely, water-lost stage, heavy-increased stage and combustion reaction stage, is creatively put forward. The activation energy and pre-exponential factor for three stages of spontaneous coal combustion is solved. And the reaction mechanism function and the relation between the coal- oxidation temperature and oxygen consumption and heat. Those provided a theory base for the research of the inclination of the spontaneous coal combustion and coal combustion period. Based on the study fruits of former scholars, the division method which uses the critical airspeed to partition "Cooling Belt" and "Oxidized Dangerous Spontaneous Combustion Belt", and the one which uses the critical oxygen concentration of coal combustion to partition "Oxidized Dangerous Spontaneous Combustion Belt" and "Extinguishing Belt" are creatively put forward. And through the experimental research, the critical oxygen concentration value of coal combustion in Dong Tan Mine of Yan Zhou is determined. Those make the partition of the spontaneous combustion belt of goaf more conform to the actuality. Based on the experiments, the relation between the temperature and the concentration of symbol gas for spontaneous coal combustion. And the symbol gas is applied to judge the coal combustion stage and state. At the same time, through the...