高地温矿井综放采空区自燃危险区域判定技术研究
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摘要
煤炭在当今世界能源结构中占有十分重要的地位,能源危机的频频发生使得人们越来越注重煤炭资源的可持续节约性开采。随着浅部煤炭资源的减少和枯竭,深部开采已成为必然趋势。随着矿井深度的增加,和浅部开采相比,深部开采有了很大的不同,其中地温和地压的加大,配风量增大,造成向采空区漏风量增加,采空区的渗透系数及其漏风范围也相应发生了变化,三带分布规律随之发生改变。煤层自然发火的危险性增加,使火灾有了上升的趋势。因此,研究高地温深井综放采空区浮煤自燃危险区域的判定技术具有重要的意义。
本文以山东省龙固煤矿1301N工作面为研究对象,采用实验研究、现场观测和数值模拟相结合的办法对高地温矿井综放采空区自燃危险区域进行了研究。首先,利用大型煤自燃发火实验台,对龙固煤矿煤样的自燃特性参数进行了实验测试研究,为高地温矿井综放采空区渗流模型的建立,以及对采空区自燃危险区域划分的现场观测提供了基础数据。其次,对1301N工作面进行现场观测,结合实验测出的煤自燃极限参数,对采空区自燃危险区域进行了判定,并得出了安全推进速度。再次,通过理论分析与现场观测相结合的方法得出工作面采空区空隙率分布、漏风通道分布及渗透率分布的规律,结合工作面实际情况,建立采空区渗流数学及物理模型并对其边界条件进行合理简化。最后,应用FLUENT软件对综放采空区的漏风状况进行了数值模拟研究,得出了采空区气体渗流强度、氧浓度、压力分布等等值线图,将模拟结果与现场观测得出的采空区自燃危险区域分布进行了对比,模拟结果与实测结果基本吻合,证明了模型的有效性及对采空区防灭火工作的指导意义。同时通过数值模拟研究了风量不同时采空区氧浓度、气体渗流速度、压力等的变化,进而研究了采空区自燃危险区域的变化。
Coal is among the most important energy resources around the world, and sustainable conservation of the coal resources becomes increasingly important. Consequently, the mine on better geologic condition and with low strata has nearly been ended, which lead to the inevitably tendency of deep exploit. Along with mine pit depth's increase, the deep mining and superficial part mining had the very big difference. And the geostatic pressure and ground temperature enlargement, matches the amount of wind to increase, creates increases to the mined out area leaking out quantity, the mined out area penetration coefficient and the leaking out area correspondingly has also changed, coal spontaneous combustion danger zones distribution rule along with it change. The coal bed spontaneous combustion's risk increased, enables the fire to have the rise tendency. Therefore, it is very necessary to research the partition of spontaneous combustion danger zone in gob of fully mechanized caving face in high ground temperature coalmine.
In this article, the 1301N working face in Longgu coal mine of Shandong province was taken as example; methods of experiment, field observation and numerical simulation were combined to study the law of loose coal spontaneous combustion. Firstly, by making the use of large experiment device of coal spontaneous combustion, experiment the property parameter of coal self-ignition, and provide basic data for setting–up of forcast model of the golf and it numerical analogue for ventilation leakage condition of the gob of fully mechanized caving face in deep and high ground temperature coalmine. Secondly, on-the-spot observe face of the 1301N working face, with the property parameter of coal self-ignition, boundary of self-heating zone is partitioned, and got the safe advancing. Thirdly, the distribution of rock pressure, porosity, leakage channels and permeability of the gob were studied through theoretical analysis and flied observation. Then a mathematical model of Seepage and air species concentration was built and simplified using the theory of heat and mass transfer in porous media. After that, distribution of oxygen concentration and the velocity of air flow in the gob were calculated by simulating the flow field using fluent software numerically. Then, with the result of simulation, contrast with the coal spontaneous combustion dangerous zones which partitioned from the observation of the workface, and its results are identical on the whole with on-the-spot of reality. Proved the model validity and eradicates the guiding sense of the control of spontaneous combustion in mined out area. Meanwhile has studied the change of oxygen concentration, the gas seepage velocity, the pressure of mined out area in different amount of wind, then studied the change of self-heating zone.
本文以山东省龙固煤矿1301N工作面为研究对象,采用实验研究、现场观测和数值模拟相结合的办法对高地温矿井综放采空区自燃危险区域进行了研究。首先,利用大型煤自燃发火实验台,对龙固煤矿煤样的自燃特性参数进行了实验测试研究,为高地温矿井综放采空区渗流模型的建立,以及对采空区自燃危险区域划分的现场观测提供了基础数据。其次,对1301N工作面进行现场观测,结合实验测出的煤自燃极限参数,对采空区自燃危险区域进行了判定,并得出了安全推进速度。再次,通过理论分析与现场观测相结合的方法得出工作面采空区空隙率分布、漏风通道分布及渗透率分布的规律,结合工作面实际情况,建立采空区渗流数学及物理模型并对其边界条件进行合理简化。最后,应用FLUENT软件对综放采空区的漏风状况进行了数值模拟研究,得出了采空区气体渗流强度、氧浓度、压力分布等等值线图,将模拟结果与现场观测得出的采空区自燃危险区域分布进行了对比,模拟结果与实测结果基本吻合,证明了模型的有效性及对采空区防灭火工作的指导意义。同时通过数值模拟研究了风量不同时采空区氧浓度、气体渗流速度、压力等的变化,进而研究了采空区自燃危险区域的变化。
Coal is among the most important energy resources around the world, and sustainable conservation of the coal resources becomes increasingly important. Consequently, the mine on better geologic condition and with low strata has nearly been ended, which lead to the inevitably tendency of deep exploit. Along with mine pit depth's increase, the deep mining and superficial part mining had the very big difference. And the geostatic pressure and ground temperature enlargement, matches the amount of wind to increase, creates increases to the mined out area leaking out quantity, the mined out area penetration coefficient and the leaking out area correspondingly has also changed, coal spontaneous combustion danger zones distribution rule along with it change. The coal bed spontaneous combustion's risk increased, enables the fire to have the rise tendency. Therefore, it is very necessary to research the partition of spontaneous combustion danger zone in gob of fully mechanized caving face in high ground temperature coalmine.
In this article, the 1301N working face in Longgu coal mine of Shandong province was taken as example; methods of experiment, field observation and numerical simulation were combined to study the law of loose coal spontaneous combustion. Firstly, by making the use of large experiment device of coal spontaneous combustion, experiment the property parameter of coal self-ignition, and provide basic data for setting–up of forcast model of the golf and it numerical analogue for ventilation leakage condition of the gob of fully mechanized caving face in deep and high ground temperature coalmine. Secondly, on-the-spot observe face of the 1301N working face, with the property parameter of coal self-ignition, boundary of self-heating zone is partitioned, and got the safe advancing. Thirdly, the distribution of rock pressure, porosity, leakage channels and permeability of the gob were studied through theoretical analysis and flied observation. Then a mathematical model of Seepage and air species concentration was built and simplified using the theory of heat and mass transfer in porous media. After that, distribution of oxygen concentration and the velocity of air flow in the gob were calculated by simulating the flow field using fluent software numerically. Then, with the result of simulation, contrast with the coal spontaneous combustion dangerous zones which partitioned from the observation of the workface, and its results are identical on the whole with on-the-spot of reality. Proved the model validity and eradicates the guiding sense of the control of spontaneous combustion in mined out area. Meanwhile has studied the change of oxygen concentration, the gas seepage velocity, the pressure of mined out area in different amount of wind, then studied the change of self-heating zone.
引文
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[2]谢和平.深部高应力下的资源开采现状、基础科学问题与展望.中国环境科学出版社,2002,179-191
[3]王显政等,煤矿安全新技术.北京:煤炭工业出版社.2002.
[4]何启林.综放面采空区遗煤自然发火过程动态数值模拟[J].中国矿业大学学报,2004,(1):11-14
[5]何启林,袁树杰,王新建,等.徐庄煤矿综放面采空区―三带‖宽度的确定[J].煤矿安全,2001,(2):6-7
[6] Smith A.C.,Lazzara C.P.Inhibition of Spontaneous combustion of coal, Report of investigation–Unites States. Bureau of mines, Pittsburgh, PA, USA 1988: 41.1-41.4
[7] Feng K.K. Spontaneous combustion of Canadian coals. CIM Bulletin.1985,78(5):71-75
[8] Gouws M.J.,Gibbon G.J. ,Wade L., Phillps H.R. Adiabatic apparatus to establish the spontaneous combustion propensity of coal. Mining science & technology 1991, 13(3):417-422
[9] Btooks Kevin, Svanas Nicoloas,Glasser David. Critical temperatures of someTurkish coals due to spontaneous combustion. Journal of Mines, Metals & Fuels.1988,36(9) :434-436
[10]陈立文.煤层自燃危险程度识别的研究.煤炭工程师,1992,(5),48~57
[11]许波云,范明训.运用模糊聚类分析法综合预测煤层自燃危险性.煤炭学报,1990,(4),9~14
[12]郭嗣琮,孙树江.煤炭自燃的模糊分类与识别.阜新矿业学院学报,1995,14(1):1~5
[13] Lazzara Charles P. Overview of U.S. Bureau of Mines Spontaneous Combustion Research[A]. Session Papers American Mining Congress Coal Convention[C]. Pulbby American Mining congress, Washington,D.C.,U.S.A.,1991,143~154
[14]邓军,徐精彩等.煤自燃性参数的测试及应用.燃料化学学报,2001.12
[15]Ren,T.X.,Edwards,J.S.Adiabatic oxidation study on the propensity of pulverized coals to spontaneous combustion. Fuel,1999,78(14):1611~1620
[16] Jones,J.C..Temperature Uncertainties in oven heating tests for propensity to spontaneous combustion. Fuel,1998,77(13):1517~1519
[17] Vance,W.E.,Chen,X.D.. The rate of temperature rise of a sulbbituminous coal during spontaneous combustion in an adiabatic device: The effect of moisture content anddrying methods. Combustion and flame,1996,106(3):261~270
[18]邓军,徐精彩,陈晓坤.煤自燃机理及预测理论研究进展.辽宁工程技术大学学报,2003
[19] N.B.潘菲若娃.确定矿体内因火灾的中心位置[J].国外煤矿安全信息,1995(6)
[20] Sujanti,Wiwik Zhang,Dong-Ke,Chen,Xiao Dong.Low-temperature oxidation of coal studied using wrie-mesh reactors with both steady-state and transient methods[J]. Combustion and Flame.1999,117(3):646~651
[21]Ren T.X., Richards M.J.. Computer system for the study of the spontaneous combustion of coal[J]. Mining Engineer (London)1994,154(398):121~127
[22]齐庆杰,黄伯轩.用计算机模拟法判断采空区自然发火位置[J].煤炭工程师,1997,(5):7~9
[23]章楚涛.采场空气流动状况的数学模型和数值方法[J],煤炭学报,1983,(3)
[24]邓军,徐精彩等.综放面采空区自燃危险区域判定技术研究[J],淮南矿业学院学报,2000,10
[25]崔洪义等编.煤炭自燃早期预测预报与火源探测技术[J],煤炭工业出版社,2002,1
[26]罗的光.红外遥感探测井下煤体自燃的研究.遥感科学进展,北京:科学出版社,1995
[27]鲍庆国,文虎,王秀林,徐精彩.煤自燃理论及防治技术,煤炭工业出版社, 2002
[28]邵辉.浅析煤炭自燃指标气体的优选与使用.煤炭科学技术,1996. 24(9):43～46
[29]阮国强.束管监测系统在矿井防灭火中的应用.煤矿安全,2000 .(8):40～421
[30]郭兴明,徐精彩,邓军,文虎,惠世恩.地温对煤自燃危险性的影响研究.西安交通大学学报.2000.11
[31] Jaluria, Yogesh. Natural convection heat and mass transfer [M]. Oxford: Pergamon Press, 1980. 18~22.
[32] Gebhart B. Heat transfer [M]. New York: McGraw-Hill, 1971. 316~402.
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