Comparison of CO₂ gasification of coal in isothermal and non-isothermal conditions

Abstract

The thermogravimetric method allows to carry out measurements both in isothermal conditions for a given temperature and in non-isothermal conditions at a set heating rate. The aim of the work was to compare the process of gasification of the same coal in an atmosphere of CO2 under isothermal and non-isothermal conditions. The measurements were carried out with the use of DynTHERM Thermogravimetric analyzer by Rubotherm. Char derived from Polish bituminous coal “Janina” was used as material for gasification. In case of the isothermal method the measurements were performed at three temperatures – 850 °C, 900 °C and 950 °C, while in case of the non-isothermal method for three heating rates, i.e. 3 K/min, 5 K/min and 10 K/min. Based on the results obtained, kinetics curves of conversion degree of the gasification process were developed and kinetic parameters of the gasification reaction i.e. reaction order, activation energy and pre-exponential factor were determined. The values of the kinetic parameters obtained from measurements performed in isothermal and non-isothermal conditions were compared.

Recent Progress on Hydrogen-Rich Syngas Production from Coal Gasification

“…In addition, the gasification reactivity of any carbonaceous material is enhanced by increasing gas temperature. Czerski et al [142] studied the gasification reaction of char-CO 2 under isothermal and non-isothermal conditions, in which the impact of temperatures on the carbon conversion rate of gasification was analyzed. A positive correlation between the reaction rate and temperature was observed.…”

Complexity Study on Multi-Field Coupling Systems for Underground Coal Fires

“…The oxidation and combustion characteristics of coal determine the reaction essence of coal and oxygen, which plays a decisive role in the occurrence and development of underground coal fires. Some scholars have experimentally determined the heat flow curves of coal during oxidation, combustion, etc., through thermal analysis techniques to obtain the kinetic parameters at each reaction stage, thus constructing a kinetic model of a coal-oxygen reaction [26,27]; some scholars have also used material analysis techniques to determine the changes in mass and microstructure of coal during oxidation, as well as various reaction products to determine the chemical essence of the coal-oxygen reaction The size of the emergence intensity indicates the increased use of the keyword in a certain period, and the greater the intensity, the more it can represent being at the forefront of research in the field. The red line indicates the time stage of the keyword as a research hotspot, the light blue line indicates the stage when the keyword does not appear, and the dark blue line indicates the stage when the keyword continues to exist.…”

“…The oxidation and combustion characteristics of coal determine the reaction essence of coal and oxygen, which plays a decisive role in the occurrence and development of underground coal fires. Some scholars have experimentally determined the heat flow curves of coal during oxidation, combustion, etc., through thermal analysis techniques to obtain the kinetic parameters at each reaction stage, thus constructing a kinetic model of a coal-oxygen reaction [26,27]; some scholars have also used material analysis techniques to determine the changes in mass and microstructure of coal during oxidation, as well as various reaction products to determine the chemical essence of the coal-oxygen reaction at each stage. The studies related to thermal analysis and material analysis techniques are listed in Table 5.…”