Study On Prevention And Control Of Rockburst Disaster By Adding Chelating Agent To Coal Seam Water Injection

Rockburst is a kind of destructive environmental geological disaster,and coal seam water injection technology can change the physical and mechanical properties and thermodynamic properties of coal,displace the gas in coal,prevent coal mine rockburst and gas outburst,gas outburst and other disasters,and at the same time reduce coal dust,which is one of the most active and effective measures to prevent and control coal mine disasters.In the process of field engineering practice,it is found that the poor wettability of most coal mines seriously affects the field water injection effect.Generally,coal mines will add surfactants to improve the water injection effect of coal seams.However,with the increase of mining depth,under the action of high ground stress,the coal seam minerals are cemented tightly,the pore throat is blocked,and the permeability of the reservoir is damaged,which leads to the characteristics of "strong adsorption and low permeability" in the coal seam,which seriously affects the water injection effect of the coal seam.Adding surfactant to improve the effect of coal seam water injection is not significant.Minerals in coal are one of the key factors that affect the physical and mechanical properties and permeability of coal body.Chelating agent can be used as an additive in coal seam water injection technology because of its special role with minerals,so as to realize the efficient prevention and control of coal mine rockburst.In this paper,tetrasodium iminodisuccinate(IDS)was selected as water injection additive to study the physical and mechanical properties of coal and the change rule of mineral elements in coal after IDS.The experimental results show that IDS can deconstruct the minerals in coal and change them from insoluble state to soluble state.With the increase of IDS concentration,the concentration of mineral ions in solution increased.After the minerals are deconstructed,the pore structure of coal is changed,and the pores that were originally in closed state are opened,so as to increase the permeability of coal.At the same time,the mechanical properties of coal body change after mineral dissolution.With the increase of IDS concentration,the impact tendency of coal decreases.Adding chelating agent to coal seam water injection can reduce the problem of particle pollution from coal burning and promote the safe mining and green utilization of coal.The results show that the addition of IDS to coal seam water injection can enhance the effect of water injection,prevent and control dynamic disasters,and provide new ideas for the possibility of coal pollution source control,which is of engineering significance.