Research On Spontaneous Combustion Control Techniques Of 5-2S Fully Mechanized Caving Face At Goaf In Hongmiao Mine

Using the methods of combining theoretical analysis, field test, indoor experiment, numerical simulation on basis of orthogonal and uniform experimental design with engineering application, the major work and the results achieved are as follows:(1) Through field sampling, thermo gravimetric analysis, infrared spectra experiment and theoretical calculation are used, characteristic temperature, ignition activation energy and spontaneous combustion period of 5-2S seam are got; the change relationship between several common gas and temperature is achieved, index gas system of spontaneous combustion adopting CO as the main and C2H4 as the supplement is established.(2) Site monitoring on goaf is developed, the distribution law of spontaneous combustion three zones under the condition of nitrogen injection and no nitrogen is respectively got, numerical simulation model of gas concentration and air flow speed in gob is formatted; through comparing numerical simulation calculation and field monitoring results, the reasonability of model is verified.(3) No matter nitrogen injection and no nitrogen, the width, the home and end position of oxidation zone are broaden with air volume increasing. Quadratic function exists between the width of oxidation zone and air volume under the condition of nitrogen injection, negative exponential function exists between them under the condition of no nitrogen injection; finally, air distribution is reasonably determined.(4) With nitrogen injection volume, its time and the distance between its position and roofcaving line increasing, the width, the home and end position of oxidation zone are significantly decreased; but the above situation has certain limit, a set of process parameters are given.Research and implementation of the above production main combustion control ensures that 5-2S fully mechanized working face safety and high efficiency mining.