THERMAL SCIENCE

International Scientific Journal

Sunel Kumar

,

Zhihua Wang

,

Shuang Wang

,

Yaw Dwamena-Akenteng

,

Ding Jiang

,

Hao Chen

A COMPUTATIONAL ANALYSIS OF OPERATIONAL PARAMETERS INFLUENCING COAL GASIFICATION IN A LAB-SCALE DROP TUBE GASIFIER

ABSTRACT
This study uses a numerical simulation for coal gasification operation in a drop tube gasifier to investigate the effects of wall temperature and oxygen-to-coal ratios on gasification. Coal gasification is an efficient approach to electricity generation, offering a cleaner alternative to conventional coal combustion methods. A 2-D CFD model of the gasifier was employed to perform grid sensitivity analysis and subsequently compute the influences of varying wall temperatures (1000 K, 1250 K, and 1500 K) and oxygen-to-coal ratios (0.6, 0.8, 1, and 1.2) on the temperature profile, syngas composition, and velocity within the gasifier. Temperature profiling within the furnace defined a spectrum of maximum and minimum temperatures, with apex values recorded at 2100 K and lowest values at 1300 K for Cases 12 and 1, respectively. High oxygen-to-coal ratios favored the production of CO2 due to enhanced combustion reactions, whereas lower oxygen-to-coal ratios were conducive to higher yields of CO and H2, essential syngas components. Velocity profiles of particles within the gasifier increased with higher temperatures and oxygen-to-coal ratios, and the maximum velocity was 9 m per second. In conclusion, this study offers valuable insights into optimizing operational parameters such as wall temperatures and oxygen-to-coal ratios to enhance the performance and efficiency of coal gasification processes in lab-scale gasifiers.
KEYWORDS
coal gasification, Oxygen-to-Coal Ratio (O/C Ratio), computational fluid dynamics (CFD), reaction kinetics, Syngas Composition
PAPER SUBMITTED: 2023-11-22
PAPER REVISED: 2024-01-11
PAPER ACCEPTED: 2024-01-23
PUBLISHED ONLINE: 2024-05-18
DOI REFERENCE: https://doi.org/10.2298/TSCI231122113K
CITATION EXPORT: view in browser or download as text file
THERMAL SCIENCE YEAR 2024, VOLUME 28, ISSUE Issue 5, PAGES [4027 - 4039]
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A computational analysis of operational parameters influencing coal gasification in a lab-scale drop tube gasifier

© 2024 Society of Thermal Engineers of Serbia. Published by the Vinča Institute of Nuclear Sciences, National Institute of the Republic of Serbia, Belgrade, Serbia. This article is an open access article distributed under the terms and conditions of the Creative Commons Attribution-NonCommercial-NoDerivs 4.0 International licence