School of Safety Engineering,Heilongjiang University of Science & Technology
School of Architecture & Civil Engineering,Hei⁃longjiang University of Science & Technology

瓦斯水合固化防突方法能高倍固化瓦斯,降低瓦斯压力,并且前期研究表明,水合物的生成填充煤体孔隙,能够提高煤体强度,改善煤体力学性质,有望减弱煤与瓦斯突出危险性。渗透率是检验瓦斯水合物-煤体体系水合固化效果的关键参数,因此利用应力-渗流-固化一体化三轴试验机,开展了3种目数和3种饱和度条件下含瓦斯煤、含瓦斯水合物煤体渗透实验,测定了瓦斯水合物生成前后煤体渗透率;基于含水合物多孔介质渗透率模型,探讨了煤体中瓦斯水合物的分布模式。结果表明:水合物生成后煤体的渗透率降幅为19.9%~93.0%,其中40~60目(0.250~0.425mm)60%饱和度煤样渗透率降低幅度最大;随着饱和度增加,20~40目(0.425~0.850mm)及40~60目(0.250~0.425mm)含瓦斯水合物煤体渗透率均先减小后增大,60~80目(0.18~0.25mm)煤样始终呈增大趋势;将试验结果与渗透率理论模型对比发现,本试验煤体中瓦斯水合物分布模式以表面胶结型为主,水合物生成对煤体内瓦斯渗流通道的阻塞效果显著。

Coal and gas outburst prevention technology based on the hydrate method can make gas hydration and reduce gaspressure. Previous study shows that the formation of gas hydrate can fill coal pores,improve coal strength and the mechan⁃ical properties of coal,which is supposed to reduce the risk of coal and gas outburst. The permeability of gas hydratebearing coal is the key parameter to test the hydration and solidification effect of gas-hydrate-coal system. Using stress-seepage - hydration integrated triaxial testing machine, the authors carried out the coal permeability experimentsunder three meshes and three saturation conditions,and determined the permeability of gas bearing coal and gas hydratebearing coal. Subsequently,the distribution modes of gas hydrate was discussed by referencing permeability modelsof hydrate porous media. The results show that under the influence of hydrate formation,the coal permeability decreasesfrom 19.9% to 93%,in which the decreased permeability of 40 - 60 mesh coal samples with 60% saturation is thelargest. With the increase of saturation,the gas permeability of 20-40 mesh and 40-60 mesh coal samples first decreasesand then increases,while that of 60-80 mesh coal samples always shows an increasing trend. Comparing the test resultswith the permeability theoretical models,it is found that the distribution mode of gas hydrate is mainly cementingmodel,hydrate formation has obvious blocking effect on gas seepage channel in coal. This research work is expected toprovide an experimental reference for gas hydration and solidification outburst prevention technology and its application.

国家自然科学基金面上资助项目(51974112,51674108);国家自然科学基金联合基金资助项目(U21A20111)

张保勇,李焕如,高霞,等. 饱和度对含瓦斯水合物煤体渗透率影响试验研究[ J].煤炭学报,2023,48(S1):122-129.

ZHANG Baoyong,LI Huanru,GAO Xia,et al. Experimental study on effect of saturation on the permeabilityof gas hydrate bearing coal[J]. Journal of China Coal Society,2023,48(S1):122-129