煤矿安全2025，Vol.56Issue(10)：69-77,9.DOI:10.13347/j.cnki.mkaq.20250153
超临界CO2对煤体多尺度孔隙结构的改造效果量化研究
Quantitative study on transformation effect of supercritical CO2 on multi-scale pore structure of coal
摘要
Abstract
In order to more accurately characterize the effect of supercritical CO2 on the pore structure of the coal and explore the mechanism of its transformation on the pore structure of the coal,low-temperature nitrogen adsorption and desorption tests and mer-cury intrusion porosimetry(MIP)tests were carried out based on the literature research and the coupled-hole method.It was con-cluded that the pore distribution results obtained from mercury intrusion porosimetry test and low-temperature nitrogen gas absorp-tion and desorption test showed differences,and joint characterization should be carried out to reduce the test error;supercritical CO2 can make the microscopic and small pores in the coal rupture gradually into medium and large pores,and the pore structure becomes more open and connected.The pore volume percentage of macropores,mesopores and small pores after supercritical CO2 treatment was found to be increasing,with increments of 3.66%,1.84%and 2.92%respectively,while the pore volume percentage of micro-pores was decreasing,with a reduction of 8.42%;the specific surface area of macropores,mesopores and small pores of the coal were also on the trend of increasing,with increments of 0.47%,3.67%and 57.65%respectively,while that of the micropores was decreas-ing,with a reduction of 61.79%.The main reason for this phenomenon is that supercritical CO2 has certain extractive pore expansion effect and adsorption and swelling effect on the pore structure of the coal,which can react with the mineral components and organic functional groups in the coal,leading to chemical dissolution process inside the coal,making the degree of adhesion between the coal particles deteriorate,and increasing the dispersion of the particles of the coal,and the coal has a strong adsorption on the supercritic-al CO2,resulting in the expansion of the pore volume and pore specific surface area of the coal.Moreover,the strong adsorption of coal to supercritical CO2 leads to the adsorption and swelling process inside the coal,resulting in the expansion of the coal matrix and the widening of the pore space,which leads to the increase of the pore volume and pore specific surface area of the coal.关键词
孔隙结构/安全工程/超临界CO2/高压压汞/低温氮气吸附脱附/联孔法/孔径分布Key words
pore structure/safety engineering/supercritical CO2/mercury intrusion porosimetry(MIP)/low-temperature nitrogen adsorption and desorption/combined pore method/pore size distribution分类
矿业与冶金引用本文复制引用
王春霞,田守强..超临界CO2对煤体多尺度孔隙结构的改造效果量化研究[J].煤矿安全,2025,56(10):69-77,9.基金项目
河南省瓦斯地质与瓦斯治理重点实验室-省部共建国家重点实验室培育基地开放课题资助项目(WS2024B06) （WS2024B06）
六盘水师范学院学科团队资助项目(LPSSY2023XKTD01) （LPSSY2023XKTD01）
六盘水师范学院高层次人才科研启动资助项目(LPSSYKYJJ202413) （LPSSYKYJJ202413）
