Experimental study and analysis on physicochemical properties of coal treated with clean fracturing fluid for coal seam water injection

[Display omitted] In the process of coal seam water injection, the components of different fracturing fluids have different effects on coal. To analyze the effect of water injection fracturing fluid on the physical and chemical properties of coal, we studied the relationship between guar-based fracturing fluid and cationic clean fracturing fluid (C-VES). Microscopic experiments show that guar-based fracturing fluid has a certain viscosity effect on coal, while C-VES can adsorb and capture the primary coal dust in coal. FTIR analysis shows that C-VES has a great change on the content of coal functional groups, and guar-based fracturing fluid has little effect on coal. Industrial analysis shows that C-VES can better reduce the ash content of coal and has a certain impact on the thermal efficiency of coal than guar based fracturing fluid. Combustion characteristic experiment shows that guar-based fracturing fluid does not affect the combustion effect of coal, and C-VES can expand the exothermic temperature range of coal but has little effect on the main combustion of coal. Molecular dynamics simulation results show that C-VES has the best wetting effect on coal. This research provides theoretical guidance for dust prevention and improving the use and conversion efficiency of coal.