SCR脱硝后低温省煤器磨损分析及结构优化  

Wear analysis and structural optimization of low temperature economizer after SCR denitrification

作　　者：李巩 叶兴联 张浩[1] 安希忠[1] Li Gong;Ye Xinglian;Zhang Hao;An Xizhong(Key Laboratory for Ecological Metallurgy of Multimetallic Mineral(Ministry of Education),Northeastern University,110819,Shenyang,China)

机构地区：[1]东北大学多金属共生矿生态化冶金教育部重点实验室,沈阳110819

出　　处：《应用力学学报》2021年第5期2049-2056,共8页Chinese Journal of Applied Mechanics

基　　金：国家重点研发计划(2016YFB0600101-4);辽宁省自然科学基金(2019-MS-125);中央高校基本科研业务费(N182504019);沈阳市中青年科技创新人才支持计划(RC170512)。

摘　　要：以某电厂选择性催化还原技术(SCR)脱硝出口烟道及低温省煤器为研究对象,采用CFD软件对烟气脱硝后烟道和低温省煤器区域内两相流流动过程进行数值模拟研究。针对低温省煤器进口板面中部受侵蚀最为严重这一现象,从改变烟道外壳形状和添加导流板两个手段入手提出五种改进方案,以期探索有效缓解设备磨损的方法。数值模拟结果表明:通过扩张烟道,降低颗粒速度,可大幅缓解进口板面局部受侵蚀程度;通过添加"垂直"导流板,增大颗粒冲击角度,可使侵蚀峰值下降10.1%;通过添加适于烟道拐角的导流板,减弱颗粒偏析程度,可使侵蚀峰值下降35.3%;微调拐角处导流板的结构和布置,对流场的速度场优化效果不明显,而对颗粒场分布影响更大,可使侵蚀峰值较微调之前降低20%。以上研究结果可为SCR脱硝设备的改造提供借鉴。Taking the selective catalytic reduction(SCR) denitrification outlet flue and low temperature economizer of a power plant as the research objects, the two-phase flow process of flue and low temperature economizer after denitrification was numerically simulated by using computational fluid dynamics(CFD)software. In view of the phenomenon that the middle of the inlet plate of low temperature economizer is most seriously eroded, five improvement schemes are proposed from the two perspectives of changing the shape of flue shell and adding deflector plate, in order to explore effective ways to alleviate the wear of equipment. The numerical simulation results show that by expanding the flue and reducing the particle velocity, the local erosion degree of the imported plate can be greatly alleviated. By adding a "vertical" guide plate and increasing the particle impact Angle, the erosion peak decreased by 10.1%. The erosion peak was reduced by 35.3% by adding a diversion plate suitable for the corner of flue gas and reducing particle segregation. By fine-tuning the structure and arrangement of the diversion plate at the corner, the optimization effect of flow field velocity field is not obvious, but had greater influence on particle field distribution, which could reduce the erosion peak by 20%compared with that before fine-tuning. The results can be used for reference for the improvement of SCR denitrification equipment.

关 键 词：SCR 低温省煤器 两相流 磨损 数值模拟 

分 类 号：TM621[电气工程—电力系统及自动化]