| The hypothesis based on coal and gas outburst is still incomplete.The formation mechanism of gas and its in-depth study will help to understand coal and gas outburst more comprehensively.The formation of gas is rarely questioned,but mine gas accidents continue to occur,indicating that the gas formation mechanism needs to be improved.The pre-study knows that the gas type has a third type of gas formed in the coal mining process in addition to the in-situ(native,first-class)gas and off-site(secondary,second-class)gas.The third type of gas can well explain why the amount of gas generated when the protrusion occurs is much larger than the original gas content in the coal.Therefore,before the prevention of coal and gas outburst,it is necessary to first clarify the formation mechanism of gas.The main research contents of this paper are as follows:(1)Based on the physical and chemical properties of the corresponding elements in coal and coal,distillate sampling is used to find the halogen elements in the coal seam,and optical intervention is carried out to study the second substance left by the carbon material to produce gas.According to the scientific theory that has been mastered,the reasons for the large amount of gas generated in the gas state of the coal seam before mining and in the mining process are analyzed and demonstrated.On the other hand,by studying the whole process of adsorption/desorption and addition(peroxidation)of carbon molecular sieves formed by decarburization and dehalogenation of fixed carbon in coal under coal hydrolysis,the gas state and mining process of coal seam before mining are analyzed.The reason for the third type of gas generation.(2)The third type of gas is deposited in the coal seam in the form of adsorption and absorption of gas.Therefore,for the gas occurrence conditions of Lianxin Coal Mine,it is necessary to analyze from the two aspects of free gas and third type gas.By analyzing the geological background of Lianxin Coal Mine,using electron microscopy to analyze the porosity of coal samples and analyzing the properties of coal samples,the gas occurrence conditions of Lianxin Coal Mine were analyzed,and the influence of gas occurrence on gas outburst was analyzed by gas occurrence conditions.(3)Through the study of the third type of gas formation mechanism,it directly reveals the relationship between water swelling,hydrolyzability,temperature,dissolved holes and gas outburst in coal.The third type of gas theory and the adsorption/desorption mechanism of carbon molecular sieves(a non-polar carbonaceous adsorbent with uniform microporous structure in coal)can explain the accidents related to mine gas and provide new ideas for mine defense.(4)Conduct research on anti-burst measures against the characteristics of Lianxin Coal Mine.The general idea is that when there is no protrusion,it is necessary to carry out the prominent prevention and control during the preparation period;after the occurrence of the protrusion,it needs to be strictly controlled during the development period;using RFPA2D-gasflow to simulate the instability phenomenon after the occurrence of gas outburst,the mine is seriously eliminated to prevent it from expanding the hazard;When the disaster is stopped,it is necessary to formulate corresponding measures to resolve the damage caused by the disaster. |
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