Effects of bedding plane on anthracite coal resistivity under different temperatures

This study tested the current vs. voltage curves of coals with angles of 0°, 30°, 45°, 60°, and 90° between the bedding plane and the axial direction at temperatures from 0 to 95℃ using a CHI660E electrochemical workstation. The concept of the series-parallel dominant degree was put forward. Moreover, the influence mechanism and the rule of the bedding structure of anthracite coal on coal resistivity under different temperatures were analyzed and investigated using the principle of minimum potential energy and polarization charge. The results show that the resistivity of the anthracite coal exhibits a strong regularity with temperature rise. A turning point appears at 55℃ for θ of the 0° samples, whereas the other samples have a turning point at 35℃. The series-parallel dominant degree reflects the impact mechanism of the bedding structure on coal resistivity and depends on the number of key bedding surface and the start time of the current going through. The resistivity increases with the increasing θ. In addition, the anisotropy coefficient of the anthracite coal increases with the temperature rise and elevates nearly twice in the scope of 35 to 65℃.