During the deep mining period of a coal mine, the mechanical properties of coal body have changed, resulting in the decrease of injectability of coal seam, and the effect of water injection in coal seam gradually deteriorates over time. In this research, chelating agent is selected to increase the effect of coal seam water injection. The experimental analysis has shown that the injected low permeability coal seam contains a certain amount of minerals which can be dissolved into ions by the chelating agent tetrasodium iminodiasuccinate (IDS), unclogging the originally closed pores, and enhancing the fluidity of water in the coal seam. The leaching amount of mineral ions in the coal seam increases gradually with the increase of the concentration of chelating agent IDS. When the concentration of IDS is 2 000 mg/L, the performance-cost ratio is the highest; the rock burst tendency of coal samples decreases by the action of IDS; the metal ions in sulfur-bearing minerals (such as pyrite) are released after chelation, which reduces the sulfur content from the source. At the same time, IDS is a degradable and environment-friendly chelating agent, providing assistance for environmental protection. Adding chelating agent to coal seam water injection can provide reference for the prevention and control of compound dynamic disasters.
