摘要
煤中的孔裂隙特性对于瓦斯运移、表面吸氧低温氧化能力等特性具有一定的影响。文章利用实验方法,系统研究了色连二矿低变质程度的2号煤层孔裂隙特性。研究发现:Ⅲ级、Ⅳ级和Ⅴ级裂隙发育较充分,裂隙宽度为3~350μm,通常为7~50μm;实验测定了Ⅱ类、Ⅲ类、Ⅳ类和Ⅴ类煤的孔容和比表面积特性,煤样的破碎程度越高,微孔及超微孔的总数及煤样的比表面积越大;随着煤的破碎性的提高,煤样的吸附容积和吸附回线中吸附曲线和脱附曲线之间的宽度不断增大。随着煤体破碎程度的增大,其孔隙分形维数D_n不断增大,当D_n<2.6时,过渡孔占主要地位,煤体的储气能力亦较强,渗流能力则较弱,当D_n>2.6时,则相反。D_n越大,煤的破碎程度越高,比表面积越大,吸附甲烷和氧的能力越强。
The pore and fissure characteristics of coal have certain influence on gas migration and surface oxygen absorption capacity.Experimental methods are used to study the pore and fissure characteristics of No.2 coal seam with low metamorphic degree in Selian No.2 Coal Mine.The results show that,levelⅢ,levelⅣand levelⅤfractures are well developed with a width of 3~350μm,usually 7~50μm;the pore volume and specific surface area characteristics of ClassⅡ,ClassⅢ,ClassⅣand ClassⅤcoals are measured,and the higher the crushing degree of coal sample is,the greater the total number of micropore and the specific surface area of coal sample are;with the increase of coal fragmentation,the adsorption capacity of coal sample and the width between adsorption curve and desorption curve in adsorption loop increase continuously.With the increase of coal fragmentation,the fractal dimension D_nof pore increases continuously.When D_n<2.6,the transition pore occupies the main position,the gas storage capacity of coal body is stronger,and the seepage capacity is weaker,and when D_n>2.6,the opposite tendency reverses.As D_nincreases,the degree of coal fragmentation,the specific surface area and the methane and oxygen adsorbing ability rise.
作者
疏义国
胡继松
SHU Yi-guo;HU Ji-song(Huaihe Energy Western Coal Power Group Co.,Ltd.,Ordos 017000,China)
出处
《煤炭工程》
北大核心
2020年第8期163-168,共6页
Coal Engineering
基金
国家科技重大专项(2016ZX05068)
安徽高校自然科学研究重大项目(KJ2017ZD10)。
关键词
长焰煤
孔隙
裂隙
氮吸附实验
比表面积
分形维数
long flame coal
pore
fissure
nitrogen adsorption experiment
specific surface area
fissure characteristics
