Abstract
Microwave heating contributes to coal fracturing and gas desorption. However, problems of low penetra-tion depth, local overheating and fracture closure exist. Coal demineralisation by acids has advantages in coal unblocking and permeability improvement, while it is difficult for acid to enter microcracks. Microwave-asisted acidification may offer an alternative. In this work, XRD, 1H-NMR, and SEM were used to evaluate the effect of microwave-assisted acidification on the microstructure of coal. Results show that kaolinite, calcite, and dolomite can be dissolved by acid. After microwave irradiation, the graphitization of microcrystalline structure of carbon improves. Microwave-assisted acidification erodes minerals in coal and enhances the graphitization degree of microcrystalline structure. Compared to individual micro-wave irradiation or acidification, the pore volume and pore connectivity can be greatly enhanced by microwave-assisted acidification. The NMR permeability of coal increased by 28.05％. This study demon-strates the potential of microwave-assisted acidification for coalbed methane recovery.
基金项目
国家自然科学基金(52274195)
国家自然科学基金(52274196)
国家自然科学基金(51904103)
国家自然科学基金()
国家自然科学基金(52174180)
Science and Technology Innovation Program of Hunan Province(2022RC1178)
湖南省自然科学基金(2022JJ20024)
湖南省自然科学基金()
湖南省自然科学基金(2021JJ30254)
Scientific Research Foundation of Hunan Provincial Education Department(21B0465)
NETL
NSTL
万方数据