Thermogravimetric study of the kinetics and characteristics of the pyrolysis of pulverized coal

Abstract

Simultaneous thermogravimetric-mass spectrometric (TG-MS) analyzer was used to investigate the pyrolysis characteristics and gas generation rule of three coal samples. Results indicated that Jing-mei (JM), Xinjiang-mei (XM), and Yan-mei (YM) coals had similar pyrolysis characteristics and gas generation law. Their pyrolysis process could be roughly divided into three stages. YM had the highest weight loss and gas generation rates among all the samples. CO and CO2 components in the escaping gas continued to increase when the temperature reached 800 °C. Coats-Redfern method was employed to calculate the activation energy of three kinds of coal at four temperature stages with different mode functions. The activation energy of the four stages of JM pyrolysis was 33.3 kJ mol-1, 2.66kJ mol-1, 88.51kJ mol-1, and 33.26 kJ mol-1. The result of XM pyrolysis was 51.29 kJ mol-1, 6.84 kJ mol-1, 47.38 kJ mol-1, and 15.65 kJ mol-1. Calculations of XM pyrolysis were 51.35 kJ mol-1, 5.11 kJ mol-1, and 117.49 kJ mol-1, 31.15 kJ mol-1 respectively.