Effect of glycerol microemulsion on coal seam wetting and moisturizing performance

Abstract

In coal mining, coal seam water injection is effective for rock burst prevention and dust suppression, and the microemulsion as a water injection agent can greatly improve the wettability of coal seams. In order to further study the effect of glycerol in microemulsion as a phase substance on the wettability of coal body after water injection in coal seam, and its role in promoting coal seam moisturizing performance, on the basis of changing the phase material, the influence of different microemulsion components on the wettability of coal is explored through the contact angle experiment and Fourier infrared spectroscopy experiment, and the effect of glycerol on the moisturizing performance of coal is analyzed through the wettability control experiment in this paper. The experimental results show that the microemulsion as a wetting agent exhibits good wettability, and the composition of the microemulsion phase material affects the formation and dissociation of the functional groups on the coal surface by the microemulsion to a certain extent. The dissociation of the functional groups on the coal surface by the surfactant components in the microemulsion dominates the wetting mechanism of coal, and the effect of glycerol molecules on the functional groups shows a certain degree of wetting promotion. In addition, glycerol molecules easily react with other molecules such as water and sulfur dioxide molecules. After being injected into the coal seam, the glycerol microemulsion has a good moisturizing effect and a certain effect of coalbed methane purification. Therefore, it has practical significance for reducing coal dust concentration on coal mining face and increasing coal seam permeability.