Research on wetting characteristics of coal dust with a new type of mine EMI dust depressant

With the improvement of the degree of mechanized mining,the amount of coal dust produced also increases. In view of the increasingly serious dust pollution in the underground working environment of coal mines,the surface tension of solution containing green high-efficiency biological dust suppressant (EMI) with different mass fractions was measured,and the contact angle,coal dust wetting rate,coal dust moisture absorption and water retention of coal dust with different particle sizes were taken as indicators. The wetting effect of EMI solution with different mass fractions on coal dust with different particle sizes were studied. The experimental results show that the contact angle of coal dust decreases gradually with the increase of mass fraction of EMI dust depressant in the solution,the time required for complete settlement of coal dust decreases gradually,the moisture absorption increases gradually,the water retention increases gradually,and the hardening property of coal samples is larger after water loss. Through analysis,the mechanism of EMI wetting coal dust are obtained:reducing the surface tension of water;increasing the wettability of the solution;reduce water loss;improve the evaporation resistance of the solution.