Original Article

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

¹ Key Laboratory for Chemical Metallurgy Engineering of Liaoning Province, University of Science and Technology Liaoning, Anshan, Liaoning 114051, PR China
² College of Chemical Engineering, North China University of Science and Technology, Tangshan, Hebei 063210, PR China
³ College of Science, North China University of Science and Technology, Tangshan, Hebei 063210, PR China

^* e-mail: chenghuan@ncst.edu.cn

Received: 16 November 2022
Accepted: 23 May 2023

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 S_ext-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 V_BJH-ext and average pore size d̄_DB display a quadratic parabolic relationship to thermoplastic parameters ΔT and LogMF. The correlations of the prediction models constructed for ΔT and LogMF with S_ext-SAST, V_BJH-ext and d̄_DB 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.