摘要
采用分形维数计算方法可以对煤的孔隙结构进行精确的定量描述。为了表征海拉尔盆地褐煤吸附孔的孔隙结构,基于液氮吸附实验、扫描电镜等手段,对研究区煤储层的吸附孔孔隙结构进行了分析,并利用FHH(Frenkel-Halsey-Hill)模型计算了煤样吸附孔分形维数,讨论了最大镜质体反射率(Ro,max)及分形维数与煤质、孔隙比表面积、总孔体积等之间的关系。研究结果表明:①研究区煤样吸附、脱附曲线可以分为A、B、C共3种类型;②A型孔隙形态为开放型的平板孔及圆筒孔,煤样具有较大的比表面积、总孔体积和较小的平均孔径;③B型孔隙形态为开放型的平板孔及楔形孔,煤样具有较小的比表面积、总孔体积和较大的平均孔径;④C型孔隙形态为一端封闭的平行板状孔及楔形孔,煤样具有较小的比表面积和较大的总孔体积、平均孔径;⑤煤孔隙表面分形维数(D1)与水分含量无关,与灰分产率呈正相关,与固定碳含量呈"U"字形关系,与Ro,max呈倒"U"字形关系;⑥孔隙结构分形维数(D2)与水分含量呈负相关,与灰分产率呈正相关,与固定碳含量呈"U"字形关系,与Ro,max无关。
The fractal dimension calculation method can be used to accurately and quantitatively describe pore structures in coal.In order to characterize the pore structures of adsorption pores in lignite in the Hailar Basin,this appear analyzed the pore structures of a dsorption pores in the coal reservoirs of the study area by means of low temperature nitrogen adsorption experiments and scanning electron microscope(SEM).In addition,the fractal dimensions of adsorption pores in the coal samples were calculated using FHH(Frenkel-HalseyHill)model,and the relationships of maximum vitrinite reflectance(Ro,max)and fractal dimension vs.coal quality,pore specific surface area and total pore volume were discussed.And the following research results were obtained.First,the adsorption-desorption curves of coal samples in the study area can be divided into 3 types,i.e.,type A,B and C.Second,type A pores are morphologically open parallel plate pores and cylinder pores with a large specific surface area and total pore volume and a small average pore diameter.Third,type B pores are morphologically open parallel plate pores and wedge shaped pores with a small specific surface area and total pore volume and a large average pore diameter.Fourth,type C pores are morphologically parallel plate pores and wedge shaped pores with one end closed,which have a small specific surface area and a large total pore volume and average pore diameter.Fifth,the fractal dimension of coal pore surface(D1)has no relationship with moisture content,a positive correlation with ash yield rate,a"U"shaped relationship with fixed carbon content and an inverted"U"shaped relationship with Ro,max.Sixth,the factional dimension of pore structure(D2)has a negative correlation with moisture content,a positive correlation with ash yield rate,a"U"shaped relationship with fixed carbon content and no relationship with Ro,max.
作者
邵龙义
李佳旭
王帅
侯海海
李建安
朱明宇
SHAO Longyi;LI Jiaxu;WANG Shuai;HOU Haihai;LI Jian'an;ZHU Mingyu(College of Geoscience and Surveying Engineering,China University of Mining and Technology,Beijing 100083,China;College of Mines,Liaoning Technical University,Huludao,Liaoning 125105,China)
出处
《天然气工业》
EI
CAS
CSCD
北大核心
2020年第5期15-25,共11页
Natural Gas Industry
基金
国家科技重大专项“东北地区中低煤阶煤层气规模开发区块优选评价”(编号:2016ZX05041-004)。
关键词
褐煤
液氮吸附实验
吸附孔
孔隙结构
分形维数
水分含量
固定碳含量
灰分产率
海拉尔盆地
Lignite
Low temperature nitrogen adsorption experiment
Adsorption pore
Pore structure
Fractal dimension
Moisture content
Fixed carbon content
Ash yield rate
Hailar Basin
作者简介
邵龙义,1964年生,教授,博士研究生导师,主要从事沉积学与煤田地质学方面的科研与教学工作。地址:(100083)北京市海淀区学院路丁11号。ORCID:0000-0001-9975-6091。E-mail:shaol@cumtb.edu.cn。
