| Shenhua Dongsheng Fine Coal Company Bulianta Mine is located in the Yijinhuoluo Banner(referred to as Yiqi)of Ikezhao League in Inner Mongolia Autonomous Region.The approved production capacity of the mine is 28Mt/a,which takes all the heights of one-time mining and all the coal seams are degraded.Longwall comprehensive mechanized coal mining method.The thickness of 2# coal seam currently being mined is about 6.8m,and the width of all working faces of 2#coal seam is about 310 m.The length of the proposed mining is about 5500 m.Since the mine is a multi-layer composite mining area,the overlying coal seam contains a large amount of accumulated water after mining.When mining the underlying working face,it is necessary to carry out the exploration and release work of the overlying goaf in advance.The mine adopts the extraction ventilation mode.Therefore,as the work of the exploration and discharge water progresses,the surface airflow and the water accumulated in the goaf will produce water and gas exchange.After the residual coal in the overlying goaf is affected by the flooding,the spontaneous combustion law may change.This will make the mine's fire prevention work more complicated and have a greater impact.In this paper,the 22310 working face of Bulianta Mine and the overlying 12311 goaf are taken as the research background.Under the various conditions affecting the spontaneous combustion of the residual coal in the goaf,the coal in the overlying goaf is subjected to water saturation.Test of spontaneous combustion characteristics of residual coal with different water content ratio under water loss,platform simulation experiment of residual coal migration and distribution law in overburden goaf,and platform simulation of coal spontaneous combustion "oxidation zone" in overburden goaf Through the comprehensive research results,the self-ignition characteristics of the water-bearing coal in the overburden water-bearing area and the oxygen concentration caused by internal air leakage and the distribution law after the migration of the residual coal are analyzed to obtain the overburden water in the Bianlian coal mine.The district provides a theoretical and practical basis for the establishment of a comprehensive mine fire prevention technology system.The main research contents are as follows:(1)By measuring the water absorption characteristics of the residual coal in the goaf of the Supplemental Mine,the temperature test is carried out on the coal samplesof different coal contents caused by water saturation and water loss,and the overburden water is determined.The spontaneous combustion characteristics of the area coal in the mine's exploration and release water conditions,find the most suitable index gas for the coal spontaneous combustion of the mine,and provide a theoretical basis for the establishment of multi-layer composite goaf self-ignition "fire prediction" system in the supplemental tower mine;(2)Using the simulation experiment platform of the migration and distribution law of the residual coal in the goaf,the migration and distribution law of the reclaimed coal in the overlying goaf are studied in the mining of the underlying working face.Analyze the distribution status of the actual residual coal in the overlying goaf,and lay the foundation for the division of the natural fire danger zone in the overlying goaf;(3)Using the “oxidation zone” simulation experiment platform of coal spontaneous combustion in the overburden water goaf area,study the distribution law of oxygen concentration in the goaf under the condition of extracting ventilation and ground leakage.Analyze the variation law of oxygen concentration in the “two roads”and“two lines”in the goaf,and divide the oxidation temperature rise zone to lay the foundation for the division of the spontaneous combustion and fire danger zone inside the goaf;(4)Through the comprehensive analysis of the experimental research contents and results,the natural fire danger zone inside the 12311 overburden watershed is divided,and the ultimate propulsion speed of the 22310 working face of the Supplemental Coal Mine is calculated.Provide guidance for the establishment of fire prevention and extinguishment system in the overburden area of the Bianta Coal Mine. |
PDF Full Text Request