Laws Of Gases Changement In Sealed Area During Fire Extinguishment And Discussion On Unsealing Conditions For Anthracite Coal Mine

The fire is a prominent disaster of coal mine in our country, causing a huge economic losses every year. It leads to coal resources wasted, serious environmental pollution and the ecological balance destruction. More seriously, massive noxious gases were released during combustion and gave rise to a pollution of atmosphere.All of these directly endanger humanity living environment.According to the fire control in New Return Air Vertical Shaft in Jincheng Yaoping coal mine, starting from the characteristics and the laws of anthracite burning, the fire causes characteristics and harms in anthracite mine were studied. The key technology of fire prevention was discussed. Through the oxidation and pyrogenation experiment on the coal sample from Yaoping, Chenzhuang and Sihe coal mine in Jincheng city, combined with noxious gases and temperature monitoring in fire area, the combustion law and the gases change law in the sealed area were studied for anthracite coal mine.Main contents and conclusions are as follows:1. Starting from the basic characteristics and Chemical Properties, the fire causes reasons, characteristics and combustion laws in anthracite mine were studied.2. Through the oxidation and pyrogenation experiment, the produce and change laws of CO, H2 and C2H4 in every temperature elevating stage, experimentally derived:the CO volume exponentially with temperature changes during anthracite temperature elevating oxidation process; the correlation of H2 and CO after 300℃was firstly studied, that the change trend of H2 and CO are same after 300℃, but H2 production rate (Δppm/ΔT) is faster, its production rate is 1-2.03 times to CO.3. According to Yaoping coal mine field data, the relationship between H2, CO, H2/CO and CO/CO2 changment and the status of sealed area were analyzed, and the correlation of H2 and CO on-site fire extinguishing process was verified, also the attenuation formula of H2 and CO during extinguish process of fire zone was obtained, the attenuation formula of H2 is y=2.3517e-0.1037t, the attenuation formula of CO is y=2.6038e-0.1015t.At last, according to the results of simulation reignition experiments, the suggestions were put forward on the unsealing conditiond for sealed fire area with high CO concentration combined with the successful unsealing in Yaoping coal mine's main incline, if the sealed fire area recovers ventilation, that the fire reignites or not is not directly related with the size of CO concentration, but the size of the total heat capacity and thermal conditions are more related.