煤炭地下气化粗煤气爆炸极限及安全性研究  

Study on Explosion Limit and Safety of Crude Gas for Underground Coal Gasification

作　　者：袁淑霞[1] 李荫虎 王创业 吴松 李嘉豪 YUAN Shuxia;LI Yinhu;WANG Chuangye;WU Song;LI Jiahao(School of Mechanical Engineering,Xi'an Shiyou University,Xi'an 710065,China;PetroChina Coalbed Methane Co.,Ltd.,Beijing 100028,China)

机构地区：[1]西安石油大学机械工程学院,西安710065 [2]中石油煤层气有限责任公司,北京100028

出　　处：《煤炭技术》2025年第1期160-166,共7页Coal Technology

基　　金：中国石油天然气股份有限公司重大科技攻关项目(2019E-25);陕西省自然科学基础研究计划(2023-JC-QN-0609)。

摘　　要：煤炭地下气化的产物为可燃气体,可能存在着火爆炸风险。因此,研究粗煤气的爆炸极限对确保煤炭地下气化安全有重要意义。但高温高压下可燃气体的爆炸极限实验极其困难,根据热自燃着火理论,通过计算常压下的着火界限并与常压下爆炸极限的实验值进行对比,计算得到修正系数,用修正系数对高温高压下的着火界限进行修正,得到可燃组分的爆炸极限,再将各可燃气体的爆炸极限按组分加权平均得到粗煤气的爆炸极限。结果表明,高温高压下可燃气体的爆炸下限极低,空气中含有微量的可燃气体就可能引发着火爆炸。为防止着火爆炸需在启停阶段采用氮气置换气化通道中的空气,营造安全气化环境。而正常气化时,粗煤气中的氧含量很难达到高温高压下粗煤气的爆炸上限,反而比较安全。研究提供了一种高温高压下计算气体爆炸极限的方法,为煤炭地下气化爆炸安全性分析提供了参考。The products of underground coal gasification are combustible gases,which may pose a risk of fire and explosion.Therefore,studying the explosion limit of raw coal gas is of great significance to ensure the safety of underground coal gasification.However,experiments to determine the explosion limit of combustible gases under high temperatures and pressures are extremely challenging.Based on the theory of thermal self-ignition,culates the ignition threshold under normal pressure and compares it with the experimental values of the explosion limit under normal pressure.A correction coefficient is derived from these calculations,which is then used to adjust the ignition threshold under hight emperatures and pressures,resulting in the explosion limit of combustible components.The explosion limit of each combustible gas is then weighted and averaged according to its components to obtain the explosion limit of raw coal gas.The results indicate that the lower explosion limit of combustible gases under high temperatures and pressures is extremely low,and even a trace amount of combustible gas in the air may cause ignition and explosion.To prevent such accidents,it is necessary to replace the air in the gasification channel with nitrogen during startup and shutdown stages to create a safe gasification environment.During normal gasification,the oxygen content in the raw coal gas rarely reaches the upper explosion limit under high temperatures and pressures,making it relatively safe.This study provides a method for calculating the explosion limit of gases under high temperatures and pressures,serving as areference for analyzing the explosion safety of underground coal gasification.

关 键 词：煤炭地下气化 爆炸极限 着火界限 温度 压力 

分 类 号：TD84[矿业工程—煤矿开采] X932[矿业工程—矿山开采]