Study On The Evaluation Index System Of Hydrogen Sulfide Hazard In Coal Mine

With the in-depth exploitation of coal resources,H₂S is paying more and more attention to the harm to coal mines,which seriously restricts the safe production and healthy development of coal mines.Due to the influence of geological conditions,the content of H₂S in coal mines is mainly distributed among Shanxi and Xinjiang.The content of H₂S in other coal mines is lower and the distribution range is narrower?Therefore,there is relatively little research on coal mine H₂S.However,due to the continuous mining of shallow and non-sulfur or less-sulfur coal seams,deep coal seams and high-sulfur coal seams are also added to the mining process,and the hazards of H₂S gas in coal mines are gradually revealed.Compared with the increasingly mature technologies for preventing and controlling gas,the research of toxic and harmful gases is gradually paid attention to,so it is urgent to study the H₂S movement law in coal mine working face and the assessment of hydrogen sulfide hazard.This project comes from the implementation plan of the key special subproject of the 13th Five-Year Plan of national key research and development program"coal mine occupational hazard assessment technology and classification management method"?2017yfc0805207?presided over by the research group.The main research are the cause and migration law of coal seam hydrogen sulfide,and the coal mine toxic hazard index system established by the research group is used to evaluate and classify coal mine hydrogen sulfide.This paper takes the hydrogen sulfide gushing from the coal mining face and the tunneling face of a mine as the research object.This paper is verified based on the measured hydrogen sulfide concentration on the spot and through the COMSOL numerical simulation.The movement rule of the surging hydrogen sulfide in the vertical and horizontal direction of the working face.The research shows that in the coal mining face,the hydrogen sulfide gas from the surrounding of the drum gradually diffuses to the downflow of the coal shearer.As the length of the roadway increases,the concentration of hydrogen sulfide becomes smaller and the distribution is more uniform.In the section of the vertical coal wall along the downwind,the distribution of hydrogen sulfide concentration gradually decreases as the distance from the coal wall increases;it gradually decreases as the distance from the floor increases.The key to preventing and curing hydrogen sulfide in the coal mining face is around the drum.At the same time,workers who are in the airflow below the coal shearer should pay attention to personal protective measures.In the driving face,hydrogen sulfide gushing from the working face mainly accumulates at the lower right end in front of the roadheader.There is also hydrogen sulfide in the horizontal direction of 1.55 m?human breathing zone?from the bottom plate,and it also flows above the boring machine during the diffusion process,which seriously threatens the lives of the workers and the driver of the boring machine.Therefore,the key to the treatment of hydrogen sulfide from the tunneling face is the lower right end in front of the tunneling machine,and workers should pay attention to personal protection.Using the coal mine poison hazard index system which is established by the research group through the Delphi method,and using the index classification evaluation method,the coal mine hydrogen sulfide hazard classification was carried out for the two mines,mine A and mine B.By comparing the evaluation of hydrogen sulfide in these two coal mines,the study shows that the risk score of mine A is 17.4,which is within the level 0 mild hazard range,indicating that the mine's hydrogen sulfide will not have a significant impact,and workers are not in danger.The risk score of Mine B is 27.7.Within the low-risk range of Class I,the hydrogen sulfide in this coal mine may cause health damage to workers.For example,if workers feel unwell or find corresponding health damage during physical examination.The weight evaluation method was used to evaluate the two coal mines,and the results obtained were consistent with the index evaluation method.