|
|
|
| EFFECT OF DIFFERENT ADSORPTIONAL GASES ON PERMEABILITY OF COAL |
(State and Local Joint Engineering Laboratory of Methane Drainage in Complex Coal Gas Seam，Chongqing University，
Chongqing 400030，China) |
|
|
|
|
Abstract Gas adsorption/desorption may influence the coal permeability after injection of CO2 or CO2/N2 mixture into unminable coalbed for enhanced coalbed methane recovery and CO2 sequestration. The laboratory experiments under constant effective stress and different gas pressures are conducted by means of self-developed triaxial gas-seepage experimental device；and the change law of permeability of coal samples under gas pressure and adsorption is discussed. The results show as follows：(1) The permeability decreases as negative exponent with the increase in gas pressure under fixed injected gas composition conditions. (2) The change in permeability of coal samples is a function of the injected gas composition. At the same pore pressure，the permeabilities of coal samples decrease after gas adsorption. The permeability reduction is the greatest for pure CO2 followed by CH4 and N2. When injecting CO2 and N2 mixtures，as the concentration of CO2 in the injected gas increases，the permeability of the coal decreases. However，as the N2 reaches a certain proportion，the permeability of coal samples will be improved. (3) The relation curves of permeability and gas pressure in loading-unloading process of gas pressure have the hysteresis phenomenon，which may be related to the gas adsorption/desorption hysteresis phenomenon in coal. Therefore，the permeability of coal is in relation to pressure path. The results have important significance for prediction and control of reservoir permeability in the process of CO2 or flue gas injection into unminable coalbed to enhance gas recovery and CO2 sequestration.
|
|
Received: 10 April 2010
|
|
|
|
| [1] TENNILLE E M，ANDRZEJ P R，TIM A M，et al. Assessing the potential for CO2 adsorption in a subbituminous coal，Huntly Coalfield，New Zealand，using small angle scattering techniques[J]. International Journal of Coal Geology，2009，77(1/2)：54–68.
[2] STEFAN BACHU. Carbon dioxide storage capacity in uneconomic coal beds in Alberta，Canada：methodology，potential and site identification[J]. International Journal of Greenhouse Gas Control，2007，1(3)：374–385.
[3] ALEXANDER K，ANDREAS B，SASCHA A，et al. A preliminary evaluation of the CO2 storage potential in unminable coal seams of the Munster Cretaceous Basin，Germany[J]. International Journal of Greenhouse Gas Control，2008，2(3)：329–341.
[4] YU H G，ZHOU G Z，FAN W T，et al. Predicted CO2 enhanced coalbed methane recovery and CO2 sequestration in China[J]. International Journal of Coal Geology，2007，71(2/3)：345–357.
[5] SHI J Q，DURUCAN S. Drawdown induced changes in permeability of coalbed：a new interpretation of the reservoir response to primary recovery[J]. Transport in Porous Medium，2004，56(1)：1–16.
[6] CUI X，BUSTIN R M，CHIKATAMARLA L. Adsorption- induced coal swelling and stress：implications for methane production and acid gas sequestration into coal seams[J]. Journal of Geophysical Research，2007，112(B10)：1–16.
[7] HARPALANI S，SCHRAUFNAGEL R A. Shrinkage of coal matrix with release of gas and its impact on permeability of coal[J]. Fuel，1991，69(5)：551–556.
[8] 尹光志，李晓泉，赵洪宝，等. 地应力对突出煤瓦斯渗流影响试验研究[J]. 岩石力学与工程学报，2008，27(12)：2 557–2 561.(YIN Guangzhi，LI Xiaoquan，ZHAO Hongbao，et al. experimental research on effect of geostress on outburst coal¢s gas seepage[J]. Chinese Journal of Rock Mechanics and Engineering，2008，27(12)：2 557– 2 561.(in Chinese))
[9] 尹光志，李小双，赵洪宝，等. 瓦斯压力对突出煤瓦斯渗流影响试验研究[J]. 岩石力学与工程学报，2009，28(4)：697–702.(YIN Guangzhi，LI Xiaoshuang，ZHAO Hongbao，et al. experimental study of effect of gas pressure on gas seepage of outburst coal[J]. Chinese Journal of Rock Mechanics and Engineering，2009，28(4)：697–702. (in Chinese))
[10] 尹光志，黄启翔，张东明，等. 地应力场中含瓦斯煤岩变形破坏过程中瓦斯渗透特性的试验研究[J]. 岩石力学与工程学报，2010，29(2)：336–343.(YIN Guangzhi，HUANG Qixiang，ZHANG Dongming，et al. Test study of gas seepage characteristics of gas- bearing coal specimen during process of deformation and failure in geostress field[J]. Chinese Journal of Rock Mechanics and Engineering，2010，29(2)：336–343.(in Chinese))
[11] 尹光志，李广治，赵洪宝，等. 煤岩全应力–应变过程中瓦斯流动特性试验研究[J]. 岩石力学与工程学报，2010，29(1)：170–175. (YIN Guangzhi，LI Guangzhi，ZHAO Hongbao，et al. Experimental research on gas flow properties of coal specimens in complete stress- strain process[J]. Chinese Journal of Rock Mechanics and Engineering，2010，29(1)：170–175.(in Chinese))
[12] 胡国忠，王宏图，范晓刚，等. 瓦斯压力对突出煤瓦斯渗流影响试验研究[J]. 岩石力学与工程学报，2009，28(12)：2 527–2 534.(HU Guozhong，WANG Hongtu，FAN Xiaogang，et al. Investigation on law of methane gas flow in coal with coal-gas outburst hazard and low permeability[J]. Chinese Journal of Rock Mechanics and Engineering，2009，28(12)：2 527–2 534.(in Chinese))
[13] 许 江，彭守建，陶云奇，等. 蠕变对含瓦斯煤渗透率影响的试验分析[J]. 岩石力学与工程学报，2009，28(11)：2 273–2 280.(XU Jiang，PENG Shoujian，TAO Yunqi，et al. Experimental analysis of influence of creep on permeability of gas-bearing coal[J]. Chinese Journal of Rock Mechanics and Engineering，2009，28(11)：2 273– 2 280.(in Chinese))
[14] 程瑞端，陈海焱，鲜学福，等. 温度对试样渗透系数影响的试验研究[J]. 煤炭工程师，1998，(1)：13–16.(CHENG Ruiduan，CHEN Haiyan，XIAN Xuefu，et al. Experiments on the effect of temperature on permeability coefficient of coal samples[J]. Coal Engineer，1998，(1)：13–16.(in Chinese))
[15] 王宏图，李晓红，鲜学福，等. 地电场作用下煤中甲烷气体渗流性质的试验研究[J]. 岩石力学与工程学报，2004，23(2)：303–306. (WANG Hongtu，LI Xiaohong，XIAN Xuefu，et al. Testing study on seepage properties of methane gas in coal under the action of geo- electric field[J]. Chinese Journal of Rock Mechanics and Engineering，2004，23(2)：303–306.(in Chinese))
[16] 隆清明，赵旭生，孙东玲，等. 吸附作用对煤的渗透率影响规律试验研究[J]. 煤炭学报，2008，33(9)：1 030–1 034.(LONG Qingming，ZHAO Xusheng，SUN Dongling，et al. Experimental study of coal permeability by adsorption[J]. Journal of China Coal Society，2008，33(9)：1 030–1 034.(in Chinese))
[17] REEVES S，GONZALEZ R，HARPALANI S，et al. Results，status and future activities of the coal-seq consortium[J]. Energy Procedia，2009，1(1)：1 719–1 726.
[18] VAN WAGENINGEN W F C，WENTINCK H M，OTTO C. Report and modeling of the MOVECBM field tests in Poland and Slovenia[J]. Energy Procedia，2009，1(1)：2 071–2 078.
[19] VAN BERGEN F，SPIERS C，FLOOR G，et al. Strain development in unconfined coals exposed to CO2，CH4 and Ar：effect of moisture[J]. International Journal of Coal Geology，2009，77(1/2)：43–53.
[20] KARACAN C O. Swelling-induced volumetric strains internal to a stressed coal associated with CO2 sorption[J]. International Journal of Coal Geology，2007，72(3/4)：209–220.
[21] 赵阳升，胡耀青. 三维应力下吸附作用对煤岩体气体渗流规律影响的试验研究[J]. 岩石力学与工程学报，1999，18(6)：651–653. (ZHAO Yangsheng，HU Yaoqing. Experimental study of the gas seepage law of rock related to adsorption under 3D stresses[J]. Chinese Journal of Rock Mechanics and Engineering，1999，18(6)：651–653.(in Chinese))
[22] 孙培德. 变形过程中试样渗透率变化规律的试验研究[J]. 岩石力学与工程学报，2001，20(增1)：1 801–1 804.(SUN Peide. Testing study of coal specimen permeability during solid deformation process[J]. Chinese Journal of Rock Mechanics and Engineering，2001，20(Supp.1)：1 801–1 804.(in Chinese)) |
|
|
|
2010, Vol. 29 
