煤层注水防治瓦斯的临界注水量确定方法  

An approach to determining the critical water-injecting volume to the coal seam to prevent gas outburst

作　　者：董家昕[1] 肖知国[1,2,3] 戚灵灵 DONG Jia-xin;XIAO Zhi-guo;QI Ling-ling(Sehool of Safety Science and Engineering,Henan Polytechnic University,Jiaozuo 454003,Henan,China;State Key Laboratory Cultivation Base for Gas Geology and Gas Control (Henan Polytechnie University),Jiaozuo 454003,Henan,China;Collaborative Innovation Center of Coal Safety Production of Henan Province,Jiaozuo 454003,Henan,China)

机构地区：[1]河南理工大学安全科学与工程学院,河南焦作454003 [2]河南省瓦斯地质与瓦斯治理重点实验室——省部共建国家重点实验室培育基地,河南焦作454003 [3]煤炭安全生产河南省协同创新中心,河南焦作454003

出　　处：《安全与环境学报》2018年第6期2183-2189,共7页Journal of Safety and Environment

基　　金：国家自然科学基金项目(51204066,41372160,51704100);河南理工大学博士基金项目(B2012–082);河南省基础与前沿技术研究项目(162300410038)

摘　　要：为了准确确定煤层注水防治瓦斯的临界注水量,从煤层注水防突机理的认识出发,提出采用实验室试验的方法,模拟测试煤层赋存条件下注入不同水量后煤样的瓦斯解吸特性,之后,通过分析第1min瓦斯解吸速度、第1min瓦斯解吸率、120min瓦斯解吸率和残存瓦斯含量来确定临界水分含量。对两个典型试验煤样的测试结果表明,第1min瓦斯解吸速度、第1min瓦斯解吸率和120min瓦斯解吸率均随注入水分的饱和度增大而减小,而残存瓦斯含量随注入含水饱和度增大而增大,4个指标值均可用二次方程较好地拟合,并最终确定出各自的临界注入含水饱和度。研究表明,提出的煤层注水临界注水量确定方法得到的结果与实践认知相符,对煤层注水优化设计有一定的指导意义。This paper intends to offer a method for laboratory tests to determine the proper critical water saturation based on our understanding of the outburst prevention mechanism.For this purpose,we have had first of all to make clear the gas desorption mechanism of the coal samples,an isothermal absorption experiment attempt we have suggested with varied injected water saturations under the condition of the actual coal seam.In the experiment,we have prepared 2 coal samples from Guhanshan and Chaohua Coal Mines by using the actual experiments respectively with different injected water saturations and the overstressed pressure conditions,whose different respective water saturations can be illustrated as 0,2%,4% and 6% respectively at the overburdened pressure conditions of 10 MPa and 15 MPa.And,then,we have managed to determine the critical water-moisture saturations by analyzing the speed of the gas desorption during the first minutes,and,then,an experiment can be done with the gas desorption rate during the first 120 minutes and the residual gas saturation 120 minutes later.The results of the above mentioned 2 typical samples through the aforementioned testing and experiments demonstrate that,with the increase of the injected water content,the speed of the gas desorption for the first minutes,the gas desorption rate for the first 120 minutes tends to decrease both for the samples,whereas the residual gas saturation may turn to increase 120 minutes later.It implies that water moisture tends to have a stronger inhibition effect for the 2 samples to get desorbed.Comparing the gas desorption speed for the first minute between the 2 samples,the harder one,that is,the Guhanshan sample,can be reduced to below its K1 threshold,i.e.0.4 mL/(g · min),whereas the softer superior coal samples tend to refuse to get lower than the critical value.Thus,all the 4 indexes can be made to well fitted with the quadratic equations,and,in turn,the water saturations critically injected can all be determined respectively in accordance with the

关 键 词：安全工程 瓦斯防治 煤层注水 临界注水量 

分 类 号：X936[环境科学与工程—安全科学]