Combustion and pyrolysis kinetics of Australian lignite coal and validation by artificial neural networks

SP Sathiya Prabhakaran, Ganapathiraman Swaminathan and Viraj V. Joshi

Energy, 2022, vol. 242, issue C

Abstract: Lignite (AL), with a calorific value of 5.9 MJ/kg is the most abundant low-rank coal used widely in power generation. AL's combustion and pyrolysis characteristics were investigated to provide scientific findings using thermogravimetric analysis under non-isothermal conditions. Methods utilized in the kinetic investigation included Vyazovkin, Flynn-Ozawa-Wall (FOW), Kissinger-Akahira-Sunose (KAS), Freidman, Doyle, Arrhenius, Freeman-Caroll, and Sharp-Wentworth. Multiple heating rate methods delivered the activation energy (Ea) as 194–211 kJ/mol (combustion) and 450–470 kJ/mol (pyrolysis). Combustion process followed two dimensional diffusional reaction (2D), volume contracting (R3) solid-state reaction mechanism models and pyrolysis followed volume contracting (R3) as determined by CR (Coats-Redfern), KC (Kennedy-Clark) methods. Master Plot method validated the mechanisms and concluded that it is of deaccelerating type. Improper combustion at a higher heating rate (50 °C/min) was indicated with an increase in burnout Tb, ignition Ti, peak Tp temperatures. Combustion indices (CHCI, IG, IB) reported highest values of 4.99 E−10 mg2 min−2 OC−3, 4.19E-05 mg2 min−3, 2.65 mg2 min−4 at lowest heating rates. AL's analytical thermal degradation behavior results were validated using artificial neural networks with best-fit models NNA 7,8. The research study offers a useful guide for spontaneous AL combustion and pyrolysis prediction on site.

Keywords: Combustion; Pyrolysis; Combustion indices; Kinetics; Artificial neural network; Solid-state reaction model (search for similar items in EconPapers)
Date: 2022
References: View references in EconPapers View complete reference list from CitEc
Citations: View citations in EconPapers (3)

Downloads: (external link)
http://www.sciencedirect.com/science/article/pii/S0360544221031984
Full text for ScienceDirect subscribers only

Related works:
This item may be available elsewhere in EconPapers: Search for items with the same title.

Export reference: BibTeX RIS (EndNote, ProCite, RefMan) HTML/Text

Persistent link: https://EconPapers.repec.org/RePEc:eee:energy:v:242:y:2022:i:c:s0360544221031984

DOI: 10.1016/j.energy.2021.122949

Access Statistics for this article

Energy is currently edited by Henrik Lund and Mark J. Kaiser

More articles in Energy from Elsevier
Bibliographic data for series maintained by Catherine Liu ().