Research And Application Of Inerting Characteristics In 230 Closed Goaf Fire Area Of Tangyang Coal Mine

Due to the influence of crushing and sealing failure of coal pillars,the coal spontaneous combustion may be induced by air leakage in the closed area.The risk of coal spontaneous combustion in the closed area is high,so it is necessary to carry out the research on fire prevention and control technology in the closed area.At present,inert explosion suppression of nitrogen injection and CO₂ injection in closed goaf will reduce the concentration of oxygen and gas in the closed area quickly,and become one of the main technical means for thermal power disaster prevention and control in the closed area.In order to effectively use CO₂ fire prevention technology to control the closed fire area,this paper studies the migration and diffusion law of CO₂ in the closed fire area,analyzes the main influencing factors,analyzes the causes of gas explosion accident in the closed area of working face 230 of Tangyang coal mine,and uses the technology of inert gas injection in the closed area to control the fire area.The paper constructs a mathematical model of inert gas injection in the closed area,and studies the diffusion law of inert gas CO₂in the closed zone by numerical simulation.The results show that the diffusion of CO₂ in the early stage of CO₂perfusion is unstable and the stable distribution is gradually formed in the later stage;the distribution law of CO₂ in the closed area is greatly affected by the air leakage intensity in the closed area,and the high concentration area is mainly concentrated in the closed area The concentration of the middle of goaf is low near the final mining line and two passes.The perfusion flow has an important influence on the diffusion range of CO₂ in the goaf.When the perfusion flow increases from 800m3/h to1600m3/h,the concentration of CO₂ in the closed area increases significantly.This paper introduces the general situation of explosion accident in the closed area of working face 230 of Tangyang coal mine,analyzes the causes of the explosion.The main cause of explosion in the closed goaf is the sealing area is not closed,continuous air leakage and oxygen supply lead to coal spontaneous combustion and explosion.Based on the analysis and judgment of disaster situation,the emergency treatment plan of fire area after 230 explosion was formulated.The measures of fast isolation and filling N₂ and CO₂ were used to control the fire area in the initial stage,and to strive for time for successful disaster relief.On the basis of initial treatment,the second stage of construction is permanently closed to form an efficient sealing of the fire area;and continuously filling CO₂ gas,the oxygen concentration in the fire area continues to decrease,O₂ drops below 5%,and CO decreases to 0ppm,which indicates that the disposal plan of the fire area is reasonable,effectively eliminating the threat of fire area and is conducive to the recovery of production of the mine.This paper has 30 pictures,2 tables,and 60 references.