Abstract
Calcination of limestone, a high temperature (∼900 °C) process that emits 44 % of the mass of limestone as CO2, is a critical process in the production of many industrially important materials. To soften the CO2-related impacts of traditional calcination, and to enable ultrafast synthesis of lime, a novel approach based on self-propagating high-temperature synthesis (SHS) has been put forward. SHS uses exothermic heat released by the combustion of fuel intermixed with the reactants to advance the reaction, and hence requires the provision of lower external temperatures. This study introduces a microstructure-guided modeling approach to understand the effect of fuel types (lignin alone or an equal combination of lignin and biomass; fuel-to-limestone ratio of 1.5, by mass) and pellet sizes (12.7 mm or 25.4 mm diameter) on the heat transfer processes in limestone-fuel pellets undergoing SHS, and to elucidate the kinetics of this reaction. The modeling framework considers different zones in a temporal temperature profile of a pellet undergoing SHS. Heat released from the combustion of fuel is explained using a heat source function, which is further validated using experiments. The use of lignin alone as the fuel results in higher pellet temperatures and consequently, higher conversion rates, even though the reaction initiation is earlier for lignin-biomass fuel combination. The simulated temperature profiles are used along with a kinetic model to determine the time-dependent degrees of conversion. The modeling approach is found to be capable of describing the effects of fuel types and pellet sizes on the initiation, duration, progress, and extent of SHS-based calcination.
Recommended Citation
S. S. Volaity et al., "Numerical Simulation Of Heat Transfer In Self-propagating High-temperature Synthesis (SHS)-based Calcination Of Limestone," Fuel, vol. 386, article no. 134226, Elsevier, Apr 2025.
The definitive version is available at https://doi.org/10.1016/j.fuel.2024.134226
Department(s)
Materials Science and Engineering
Second Department
Civil, Architectural and Environmental Engineering
Keywords and Phrases
Calcination; Kinetics; Limestone; Numerical simulation; Self-propagating high-temperature synthesis (SHS)
International Standard Serial Number (ISSN)
0016-2361
Document Type
Article - Journal
Document Version
Citation
File Type
text
Language(s)
English
Rights
© 2025 Elsevier, All rights reserved.
Publication Date
15 Apr 2025
Included in
Ceramic Materials Commons, Civil and Environmental Engineering Commons, Structural Materials Commons
Comments
Arizona State University, Grant DMR 2228782