The nanoscale pore characteristics of coking coals. Part 4: The relationship between nanoscale pore characteristics and Gieseler fluidity

Abstract

The nanoscale pore characteristics of six coal samples was determined using low-temperature N2 physisorption method in Part 3 of this series of articles [Cheng et al., Metall. Res. Technol. 114, 117 (2017)], and the possibility of nanoscale pore structure parameters to supplement and improve the existing coking coal property evaluation system is preliminarily demonstrated. The study focused on the relationship between nanoscale pore characteristics and Gieseler fluidity. The results show that external specific surface areas Sext-SAST and Gieseler fluidity thermoplastic parameters (plastic range ΔT and maximum fluidity MF expressed in logarithmic form) exhibit a primary linear relationship. External pore volume VBJH-ext and average pore size d̄DB display a quadratic parabolic relationship to thermoplastic parameters ΔT and LogMF. The correlations of the prediction models constructed for ΔT and LogMF with Sext-SAST, VBJH-ext and d̄DB as independent variables reached 0.97 and 0.96, respectively, indicating that the nanoscale pore characteristics are closely related to the Gieseler fluidity, and can play an important role in predicting the thermoplasticity of coking coals.