Comparing adsorption behavior of carbon dioxide, methane and nitrogen on coal and shale: particle size effect on pore characterization of coal from low temperature nitrogen adsorption test

摘要

In-depth understanding of pore characterization of coal is very important for understanding gas transport in coal and the dynamic interaction between gas and coal, which is crucial for carbon dioxide storage in unmineable coal seams and enhanced coalbed methane recovery. However, because of the lack of international standard of nitrogen adsorption tests on coal, the published data for pore characterization of coal from these tests are not comparable and inconsistent. This paper tries to investigate how the particle size of coal influences the adsorption behavior of nitrogen on coal. The pore size distributions of coal determined by both BJH and NLDFT models from nitrogen adsorption isotherms are also compared and evaluated to understand their difference and similarity.