THERMAL SCIENCE

International Scientific Journal

Authors of this Paper

External Links

Wei Bai

,

Jun-Xiao Feng

,

Yu-Jie Zhao

,

Huan-Bao Fan

COUPLING SELECTIVE CATALYTIC REDUCTION PROCESS INSIDE A COKE OVEN REGENERATOR: THE INFLUENCE OF MIXING PARAMETERS ON NO REDUCTION

ABSTRACT
Many coking plants have adopted the process of preheating flue gas to apply medium and low temperature selective catalytic reduction (SCR) denitrification technology, which increases the NOx treatment cost, fuel consumption, and generates secondary pollutants. Based on the unique temperature distribution characteristics of the coke oven regenerator, this work proposes a method for synergizing SCR inside the regenerator to remove NOx. A 3-D numerical model of the synergy between heat storage and SCR reaction was constructed to study the influence of mixing parameters (atomization angle, injection velocity, nozzles number) on the NO reduction and NH3 distribution. The validity of the model was verified. The results showed that the uneven distribution of NH3 near the catalytic layer and the small SCR coating area limited the NO reduction efficiency. Increasing the number of nozzles was more beneficial than the injection velocity and atomization angle for improving the NH3 distribution uniformity and NO reduction efficiency, achieving a maximum NO reduction efficiency of 37.1% (reduced to 251.6 mg/m3). Further research found that the NO reduction capacity of the co-operative SCR model cannot exceed 36% without changing the thermal storage brick structure. When the inlet NO concentration is less than 235 mg/m3, the reaction model ensures that the outlet NO concentration meets the national emission standards.
KEYWORDS
selective catalytic reduction (SCR), coke oven regenerator, coupling process, numerical simulation, uniformity distribution, NO reduction
PAPER SUBMITTED: 2021-11-06
PAPER REVISED: 2022-03-03
PAPER ACCEPTED: 2022-03-04
PUBLISHED ONLINE: 2022-05-22
DOI REFERENCE: https://doi.org/10.2298/TSCI211106056B
CITATION EXPORT: view in browser or download as text file
THERMAL SCIENCE YEAR 2022, VOLUME 26, ISSUE Issue 6, PAGES [4571 - 4582]
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Coupling selective catalytic reduction process inside a coke oven regenerator: The influence of mixing parameters on NO reduction

© 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