Numerical Study on the Denitration Characteristics of Coke Oven Regenerative Coupled SNCR+SCR

被引:0
|
作者
Zhao Y. [1 ]
Feng J. [1 ]
Li W. [2 ]
Chen Y. [3 ]
机构
[1] School of Energy and Environmental Engineering, University of Science and Technology Beijing, Haidian District, Beijing
[2] Anshan Iron and Steel Research Institute, Anshan
[3] School of Chemistry, Chemical Engineering and Environment, Minnan Normal University, Zhangzhou
关键词
Coke oven regenerator; Coupled denitrification; NO reduction; Numerical simulation; Selective catalytic reduction(SCR); Selective non-catalytic reduction (SNCR) +;
D O I
10.13334/j.0258-8013.pcsee.211246
中图分类号
学科分类号
摘要
Aiming at the current problems of coke oven flue gas application selective non-catalytic reduction(SNCR) or selective catalytic reduction(SCR) process denitration, a three-dimensional model of coupled SNCR+SCR in a new regenerator with ammonia injection space was established. Through the numerical simulation method, the heat storage index of different material physical parameters was optimized and evaluated, and the temperature and NO/NH3 concentration distribution characteristics of SNCR and SCR reaction zone were analyzed. The results showed that the coupled process occurred sequentially from SNCR to SCR, and it had obvious temperature gradient variation and cascade utilization characteristics of waste heat. The residence time in the SNCR reaction zone wais relatively large, ensuring the mixing degree of NH3 and NO, and achieving a NO reduction efficiency of 63.8%. In addition, the SNCR process also hads a competitive reaction of NO reduction and NH3 oxidation, and the main reaction zone wais located above the injection surface. Due to the low concentration and uneven distribution of NH3, the SCR reaction zone had a low reduction efficiency, which wais related to the structure of the regenerator and the catalyst coating area. However, the NO reduction efficiency of about 36% wais obtained in a single SCR process. It indicateds that the coupled process that NO reduction in the SNCR process and further reducing the NH3 in the SCR process couldan achieve the outlet NO/NH3 concentration to meet the emission standard, providing a theoretical basis for replacing the epitaxial SCR denitrification system. © 2022 Chin. Soc. for Elec. Eng.
引用
收藏
页码:1504 / 1513
页数:9
相关论文
共 29 条
  • [21] JI Peidong, GAO Xiang, DU Xuesen, Et al., Relationship between the molecular structure of V<sub>2</sub>O<sub>5</sub>/TiO<sub>2</sub> catalysts and the reactivity of SO<sub>2</sub> oxidation, Catalysis Science & Technology, 6, 4, pp. 1187-1194, (2016)
  • [22] ZHENG Chenghang, XIAO Lifeng, QU Ruiyang, Et al., Numerical simulation of selective catalytic reduction of NO and SO<sub>2</sub> oxidation in monolith catalyst, Chemical Engineering Journal, 361, pp. 874-884, (2019)
  • [23] ZHAO Yujie, FENG Junxiao, HUANG Shiping, Et al., Analysis and evaluation of the influence of heat storage material on coke oven flue gas exothermic process, Thermal Science, 25, 2A, pp. 1095-1108, (2021)
  • [24] OSTBERG M, DAM-JOHANSEN K, JOHNSSON J E., Influence of mixing on the SNCR process, Chemical Engineering Science, 52, 15, pp. 2511-2525, (1997)
  • [25] BROUWER J, HEAP M P, PERSHING D W, Et al., A model for prediction of selective noncatalytic reduction of nitrogen oxides by ammonia, urea, and cyanuric acid with mixing limitations in the presence of CO, Symposium(International) on Combustion, 26, 2, pp. 2117-2124, (1996)
  • [26] ROTA R, ANTOS D, ZANOELO E F, Et al., Experimental and modeling analysis of the NO<sub>x</sub>OUT process, Chemical Engineering Science, 57, 1, pp. 27-38, (2002)
  • [27] CHEN C T, TAN Weilun, Mathematical modeling, optimal design and control of an SCR reactor for NOx removal, Journal of the Taiwan Institute of Chemical Engineers, 43, 3, pp. 409-419, (2012)
  • [28] LEE G W, SHON B H, YOO J G, Et al., The influence of mixing between NH<sub>3</sub> and NO for a De-NOx reaction in the SNCR process, Journal of Industrial and Engineering Chemistry, 14, 4, pp. 457-467, (2008)
  • [29] LU Zhimin, LI Wenqing, LIAO Yongjin, Et al., Influential factors-based optimization simulation of ammonia injection in SCR DeNO<sub>x</sub> system, Proceedings of the CSEE, 41, 14, pp. 4923-4930, (2021)