水泥窑炉SCR脱硝反应塔流场优化的数值模拟研究

doi:10.16552/j.cnki.issn1001-1625.2024.1024

摘要/Abstract

摘要： 选择性催化还原(SCR) 脱硝是水泥窑炉烟气NO_x深度减排的迫切需要。本文以烟气处理量10 000 Nm³/h的水泥窑炉SCR脱硝反应塔为研究对象,利用计算流体力学(CFD)数值模拟对反应塔入口不同均布方式进行分析比对,探讨了反应塔内流场优化方法。结果表明,在反应塔烟道入口中部和渐扩口段烟道合理安装导流板、在反应塔顶部入口安装多孔均布板具有优良的流场均化效果,且多孔均布板发挥了重要作用。通过均布装置优化组合,实现反应塔内顶层催化剂床层上方速度相对标准偏差C_v达8.45%,最大入射角为9.53°,系统整体阻力仅增加37 Pa。此外,催化剂床预留层置于顶层设计时流场优化效果更佳,此时C_v可降至6.73%。本研究有望为水泥窑炉SCR脱硝反应塔流场进一步设计优化提供参考。

关键词: 水泥窑炉, SCR脱硝, 反应塔, 流场优化, 数值模拟

Abstract: Selective catalytic reduction (SCR) denitrification is an urgent need for deep emission reduction of flue gas NO_x in cement kiln. In this paper, the SCR denitrification reactor of a cement kiln with a flue gas treatment capacity of 10 000 Nm³/h was taken as the research object, and the computational fluid dynamics (CFD) numerical simulation was used to analyze and compare the different distribution modes of the reactor inlet, and the flow field optimization method in the reactor was discussed. The results show that the reasonable installation of guide plate in the middle and gradual expansion section of the reactor flue inlet, and the installation of porous uniform distribution plate at the top entrance of the reactor have excellent flow field homogenization effect. The installation of porous uniform distribution plate plays an important role. Through the optimal combination of the homogeneous distribution device, the relative standard deviation C_v of the velocity above the top layer catalyst bed in the reactor reaches 8.45%, the maximum incidence angle is 9.53°, and the overall resistance of the system increases by only 37 Pa. Furthermore, when the reserved layer of the catalyst bed is placed in the top-level design can obtain the better optimal effect of flow field, and C_v of speed can be reduced to 6.73%. This paper is expected to provide reference for further optimization design of SCR denitrification reactor of cement kiln.

Key words: cement kiln, SCR denitrification, reactor, flow field optimization, numerical simulation

中图分类号:

TQ172

王昕, 张金山, 郑旭, 杜勇, 刘晨, 潘美晨, 汪澜. 水泥窑炉SCR脱硝反应塔流场优化的数值模拟研究[J]. 硅酸盐通报, 2025, 44(5): 1612-1621.

WANG Xin, ZHANG Jinshan, ZHENG Xu, DU Yong, LIU Chen, PAN Meichen, WANG Lan. Numerical Simulation of Flow Field Optimization in SCR Denitrification Reactor of Cement Kiln[J]. BULLETIN OF THE CHINESE CERAMIC SOCIETY, 2025, 44(5): 1612-1621.

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