Interpretation of combustion properties of raw-pyrolyzed lignite with kinetic data


Korkmaz A. A. , Akbulut Y.

INTERNATIONAL JOURNAL OF COAL PREPARATION AND UTILIZATION, 2022 (Journal Indexed in SCI) identifier

  • Publication Type: Article / Article
  • Publication Date: 2022
  • Doi Number: 10.1080/19392699.2022.2104266
  • Title of Journal : INTERNATIONAL JOURNAL OF COAL PREPARATION AND UTILIZATION
  • Keywords: Lignite, kinetic analyses, pyrolysis, Arrhenius, Coats-Redfern, COAL PYROLYSIS, TURKISH LIGNITES, TEMPERATURE, REACTIVITY

Abstract

This study investigated the pyrolysis properties and kinetic behavior of Ermenek (Konya, Turkey) lignite. For this purpose, lignite was carbonized at 500 degrees C and different heating rates (5, 10, 15, and 20 degrees C/min). Proximate, elemental, XRF, and TGA-DTA lignite and chars were performed. Thermal analyses were performed at a heating rate of 10 degrees C/min from room temperature to 1000 degrees C and an inert (N-2) gas flow of 50 ml/min. Peak temperatures and mass losses were determined from the data obtained from the experiments. By examining the thermogram curves, three different temperature regions depended on moisture loss, the release of volatile matter, and fixed carbon combustion. In addition, from these data, kinetic calculations were performed using Arrhenius and Coats-Redfern approaches, and the apparent activation energies were calculated for each region. The activation energy values calculated according to the Coats-Redfern kinetic model are significantly lower than those calculated according to the Arrhenius kinetic model. The highest activation energies calculated were: for Region 1 and Region 2 at 5 degrees C/min heating rate and for Region 3 at 10 degrees C/min heating rate.