Influence of Air−entraining Agent Type on the Performance of Full Tailings Slurry and Mechanism of Action

Air−entraining agents have been gradually popularized and applied in mine filling, but the effects and mechanisms of air−entraining agents on the flow properties of full tailings sand slurry are still controversial. Accordingly, the effects of sodium dodecyl sodium dodecyl sulfate and tetradecyl trimethyl ammonium bromide on the flow and rheological properties of all−tailed sand slurry were experimentally investigated, and the mechanism of the effects of these two types of air−entraining agents on the whole−tailed sand slurry was investigated by applying the theory of double electric layer. The experimental results showed that the inclusion of cationic type of air−entraining agent could improve the flow, yield stress and viscosity of the slurry; the inclusion of anionic type of air−entraining agent at lower dosage could also reduce the flow, yield stress and viscosity of the slurry and improve the flow of the slurry; however, the inclusion of higher dosage of the slurry increased the yield stress and viscosity of the slurry, and reduced the fluidity. According to the theory of double electric layer, the air−entraining agent changes the surface charge density of the particles by adsorbing on the surface of the particles, which affects the thickness of the double electric layer and the ion distribution, and influences the rheological properties of the slurry. Therefore, it is of great significance to select the type of air−entraining agent and optimize its dosage according to the filling requirements of mines.