摘要
针对钻屑瓦斯解吸指标K1在现场测定过程中由于人员操作、仪器性能、工艺缺陷、暴露时间、钻孔布置等因素导致瓦斯损失量较大,造成K1临界值测定不准确,误差达到30%等问题,通过实验室实测方法对安徽、山西、贵州、河南、重庆、云南等6个地区59个煤矿153个煤样在实验室进行了瓦斯放散初速度指标ΔP和K1∝P关系模型的试验测定,确定出实测(K1)0.74临界值,分析了ΔP与K1∝P关系模型中的待定系数A呈幂函数关系以及待定系数B的取值,得出了6个地区钻屑瓦斯解吸指标K1与ΔP的量化关系,建立了当瓦斯压力为0.74 MPa时,6个地区钻屑瓦斯解吸指标(K1)0.74-ΔP临界值关系模型。试验结果表明:相对实测(K1)0.74临界值,关系模型(K1)0.74临界值绝对值最大误差为17.87%,最小误差为0.53%,最大误差小于30%,说明通过(K1)0.74-ΔP临界值关系模型确定钻屑瓦斯解吸指标临界值具有一定的准确性和可靠性。试验结果也说明了在相同的临界瓦斯压力条件下,K1临界值的大小主要取决于ΔP,而ΔP在实验室测定仅需4 h,对同一地区煤矿煤层,利用(K1)0.74-ΔP临界值关系模型,可以快速确定出煤层钻屑瓦斯解吸指标临界值,为确定矿井区域措施效果检验指标临界值以及进行突出危险性预测预报提供科学依据和理论指导。
The field measurement for critical value of drilling cutting gas desorption index K1 is not accurate due to high gas loss caused by personnel operation,equipment performance,process defect,exposure time and borehole layout.The measurement error for K1 could be as high as 30%.To solve this problem,this paper conducted laboratory experiments to study the correlation between the initial gas radiation velocity index(ΔP)and(K1∝P).153 coal samples were collected from 59 coal mine of six regions,including Anhui,Shanxi,Guizhou,Henan,Chongqing,and Yunnan.The coal samples were tested to determine the critical value of measured(K1)0.74.The power function of the undetermined coefficient A and the value of the undetermined coefficient B were also analyzed.Then the relationship between drilling cutting gas desorption index K1 and gas radiation initial velocity indexΔP in six regions were analyzed.Furthermore,a mathematical model for(K1)0.74-ΔP when gas pressure is 0.74 MPa for the six regions was established.The result shows that,compared to the measured(K1)0.74,the maximum error of the modeled(K1)0.74 is 17.87%and the minimum error is 0.53%.The maximum error less than 30%indicates that utilizing the model to determine the critical value of drilling cutting gas desorption index(K1)0.74-ΔP critical value is accurate and reliable.The test results also show that under the same gas pressure,K1 critical value mainly depends onΔP which can be determined in laboratory in four hours.The(K1)0.74-ΔP critical value model can rapidly and accurately determine the sensitive indicators of working face outburst(critical value K1)for coal seams in the same regions.This paper provides scientific basis and theoretical guidance for determination of the critical value to evaluate effect of outburst prevention measures and outburst risk prediction.
作者
雷红艳
LEI Hongyan(State Key Laboratory of the Gas Disaster Detecting,Preventing and Emergency Controlling,Chongqing400037,China;China Coal Technology and Engineering Group Chongqing Research Institute,Chongqing400037,China)
出处
《煤炭科学技术》
CAS
CSCD
北大核心
2019年第8期129-134,共6页
Coal Science and Technology
基金
国家自然科学基金资助项目(51774319,51874348)
关键词
钻屑瓦斯解吸指标K1
K1临界值
瓦斯放散初速度指标ΔP
量化关系
drilling cutting gas desorption index K1
K1critical value
gas radiation initial velocity indicatorΔP
quantitative relation
