With the development of coal mining industry, coal mine safety accidents and on-site safety management are more and more concerned. Firstly, we introduce the CBM transportation model of multi-seam system, based on Fick's law of diffusion and Darcy's law of permeability, and put forward a three-dimensional CBM transportation model with additional overflow state, which covers diffusion, seepage and overflow, and provides theoretical support for solving the problems of coal mine engineering, and points out that the model has not considered the influence of environmental factors such as electric field, temperature, and so on. Then, the source and outflow of gas from close double-seam mining are analyzed, including the calculation methods of gas outflow from the mined seam and the neighboring seams, and the gas outflow from the working face is obtained by adding the two together. It also introduces the rules of coalbed methane transportation and enrichment in mines with depleted coal resources, divides the types of residual coal and residual gas, and explores the transportation and enrichment of near horizontal coal seam single mining airspace and tilted coal seam adjacent mining airspace, and finds that residual gas of the mines with depleted coal resources exists in the airspace and other parts of the mines, and the transportation and enrichment of which are affected by a variety of factors, and the results of residual gas transportation are improved for the treatment of coalbed mining. The results of the transportation will provide a reference for the study of coalbed methane management.

Guo Ronghui. Research on gas transportation law in coalbed methane under different coal seam states. Academic Journal of Engineering and Technology Science (2026), Vol. 9, Issue 4: 13-18. https://doi.org/10.25236/AJETS.2026.090402.

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