发电技术 ›› 2024, Vol. 45 ›› Issue (6): 1087-1094.DOI: 10.12096/j.2096-4528.pgt.23176

• 发电及环境保护 • 上一篇    

减缓脱硫塔除雾器堵塞的流场优化方法

刘卓, 陈冬林, 汪淑奇, 杨仪江, 闫优洋, 杨展   

  1. 长沙理工大学能源与动力工程学院,湖南省 长沙市 410114
  • 收稿日期:2024-06-20 修回日期:2024-09-25 出版日期:2024-12-31 发布日期:2024-12-30
  • 通讯作者: 陈冬林
  • 作者简介:刘卓(1997),男,硕士研究生,主要从事高效清洁燃烧技术与污染物排放控制研究,1173402777@qq.com
    陈冬林(1963),男,博士,教授,主要从事高效低污染燃烧技术与热力设备及系统性能优化研究,本文通信作者,chendl_01@126.com
    汪淑奇(1966),男,博士,副教授,主要从事锅炉燃烧与传热、烟风道优化改造的理论与技术开发、应用研究,cswangsq@qq.com
  • 基金资助:
    国家自然科学基金项目(52104391)

Optimization Method of Flow Field for Alleviating Clogging of Mist Eliminator in Desulfurization Tower

Zhuo LIU, Donglin CHEN, Shuqi WANG, Yijiang YANG, Youyang YAN, Zhan YANG   

  1. School of Energy and Power Engineering, Changsha University of Science and Technology, Changsha 410114, Hunan Province, China
  • Received:2024-06-20 Revised:2024-09-25 Published:2024-12-31 Online:2024-12-30
  • Contact: Donglin CHEN
  • Supported by:
    National Natural Science Foundation of China(52104391)

摘要:

目的 脱硫塔除雾器因其结构简单、除雾效果好而广泛应用于燃煤火电厂。然而,除雾器因自身气水分离原理的局限性,容易在板面上结垢堵塞,严重时影响机组的输出功率。因此,需要解决湿法脱硫塔除雾器频繁结垢堵塞及由此造成的阻力损失过大问题。 方法 提出了采用导流板优化脱硫塔及其进口烟道流场的方法,并对优化前后的Z形脱硫塔及其L形进口烟道烟气流场进行了仿真计算和工程应用验证。 结果 仿真计算结果显示,在额定锅炉负荷工况下,优化后L形进口烟道出口截面的速度相对标准差从27.57%降至19.99%;Z形脱硫塔内除雾器入口截面的速度相对标准差从45.66%降至40.24%。同时,除雾器入口截面的浆液液滴质量流量从441.136 kg/s降至368.498 kg/s,这表明优化方案有效降低了除雾器的工作负荷。实验结果表明,改造前脱硫塔除雾器入口截面存在速度为0 m/s的区域,改造后该区域速度提升至1~5 m/s,与仿真计算结果趋势一致。改造后180天的运行数据显示,除雾器前后压差不再超过200 Pa。停机检修中实测结果显示,除雾器板面上的结垢厚度从改造前的1 cm以上减小至0.1 cm左右,严重结垢堵塞现象已消除。 结论 所提流场优化方法显著改善了脱硫塔内烟气流场的均匀性,降低了除雾器的工作负荷,有效减缓了除雾器结垢堵塞问题,具有较大的工程应用价值。

关键词: 燃煤机组, 脱硫塔, 锅炉, 除雾器, 堵塞, 流场均匀性, 烟气脱硫, 数值模拟

Abstract:

Objectives Desulfurization tower mist eliminator is widely used in coal-fired power plants due to its simple structure and good fog removal effect. However, due to the limitation of its own gas-water separation principle, it is prone to scaling up and blocking on the plate surface, which seriously affects the output power of the unit. Therefore, it is necessary to solve the problem of frequent scaling and clogging of the wet desulfurization tower mist eliminator and the resulting excessive resistance loss. Methods The method of optimizing the flow field of desulfurization tower and its inlet flue using deflector plates was proposed, and the simulation calculations and engineering application verifications of the Z-shaped desulfurization tower and its L-shaped inlet flue before and after optimization were carried out. Results The simulation results indicate that under rated boiler load conditions, the relative standard deviation of the velocity at the outlet section of the L-shaped inlet flue decreases from 27.57% to 19.99% after optimization. The relative standard deviation of the velocity at the inlet section of the mist eliminator in the Z-shaped desulfurization tower decreases from 45.66% to 40.24%. Meanwhile, the mass flow rate of the slurry droplets at the mist eliminator inlet section drops from 441.136 kg/s to 368.498 kg/s, indicating that the optimization scheme effectively reduces the workload of the mist eliminator. Experimental results show that prior to the modification, there were regions with a velocity of 0 m/s at the mist eliminator inlet section, which are improved to a velocity of 1-5 m/s after the modification, consistent with the trends observed in the simulation. Data from 180 days of operation after the modification indicate that the pressure drop before and after the mist eliminator does not exceed 200 Pa. On-site measurement results during maintenance show that the scaling thickness on the mist eliminator plate is reduced from over 1 cm before the modification to about 0.1 cm, eliminating severe scaling and blockage phenomena. Conclusions The proposed flow field optimization method significantly improves the uniformity of the flue gas flow field in the desulfurization tower, reduces the workload of the mist eliminator, and effectively slows down the fouling problem of the mist eliminator, which has great engineering application value.

Key words: coal-fired unit, desulfurization tower, boiler, mist eliminator, clogging, flow field uniformity, flue gas desulphurization, numerical simulation

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