Predication And Control Of Coal Spontaneous Combustion In Gob Around Laneway In WangFenggang Coalmine

Some laneways need to pass through gob in old coalmines. As residual coal in the gob has suffered oxidation and its temperature is somewhat higher, danger of spontaneous combustion becomes much higher once air is supplied again. Nevertheless, it is necessary to study fire preventing and extinguishing technique in such conditions to ensure safety.The prediction and control technology is researched by the methods of theoretical analysis , mathematical simulation and has application in the spot. Firstly, with the programmed temperature experiment, the reaction character with various sizes under different temperature which can provide basic data for numeric simulation is attained. Secondly, the target systems of coal spontaneous combustion fatalness evaluation formed by coal spontaneous combustion characteristics, specific air-leakage, temperature of surrounding rock and coal, parameters of laneway, moisture, voidage, particle size is pointed out and analyzed, and a fuzzy comprehensive evaluation model of coal spontaneous combustion danger is established and applied. Thirdly, by using the on-the-spot observational data and experiment data, equation of osmosis coefficient of different depth, influence function of oxygen consumption with depth, and mathematical model of diffusion of air leakage in the gob, and set up forecast model. Based on the observational data and three-dimensional model for laneway through gob, by using fluid calculation software FLUENT, ventilation leakage condition in the gob can be numerically simulated, and its results are identical with on-the-spot observational data on the whole. By changing boundary conditions, the dangerous zones and the preventive measure are found. Finally, according to the prediction and evaluation results,the fire preventing and extinguishing technology is applied to dangerous zones. Laneway drill through gob successfully and not appear self-ignite symptom.