脱硝后空气预热器硫酸氢铵堵灰在线监测

发布时间：2018-06-07 09:28

  本文选题：空气预热器 + 数值计算　； 参考：《华北电力大学(北京)》2017年硕士论文

【摘要】：随着环保问题的日益加重,我国对燃煤发电厂的污染物排放要求越来越严格,国内大多数电厂已经加装选择性催化还原(SCR)脱硝装置来控制NOx的排放。但SCR脱硝装置中催化还原NOx的过程中还会发生副反应生成具有粘性和腐蚀性的硫酸氢铵(ABS)。本文针对电厂投运脱硝系统后引起空气预热器受热面ABS沉积,进而引起的堵灰问题,分析了ABS的形成过程及影响因素,结合ABS凝结特性和运行沉积特点,给出沉积区域确定方法,得出电厂空气预热器中ABS沉积区域对应的温度区间为150℃~190℃。根据空气预热器受热面特点,描述了空气预热器温度场的离散数值计算方法,并以某1000MW电厂配套空气预热器为实例计算空气预热器内部传热元件及工质流体温度场。根据温度场计算结果绘制了内部各种温度特性曲线,分析回转式空气预热器的工作原理和传热元件及工质流体的温度分布特点。依据计算结果绘制传热元件的温度特性曲线,结合ABS沉积区域预测模型得出各个工况下传热元件沉积区域范围,得出了ABS沉积区域随负荷降低而向高温受热面扩展的情况。根据实际运行中的烟气中NH3和SO3浓度及计算的温度场结果计算Radian数,并结合监测的烟气阻力来分析空气预热器中的堵灰情况及发展趋势。根据计算模型开发Matlab计算程序,结合输入输出参数及温度场云图设计GUI用户在线监测界面。
[Abstract]:With the increasing environmental protection problems, the emission requirements of pollutants from coal-fired power plants are becoming more and more stringent. Most power plants in China have installed selective catalytic reduction (NOx) denitrification units to control the emission of NOx. However, in the process of catalytic reduction of NOx in SCR denitrification plant, the side reaction will also occur to form a viscous and corrosive ammonium bicarbonate. In view of the ABS deposition on the heating surface of air preheater caused by the operation of denitrification system in power plant, the formation process and influencing factors of ABS are analyzed in this paper, combined with the condensation characteristics and operational deposition characteristics of ABS. The method of determining deposition area is given, and the corresponding temperature range of ABS deposition area in air preheater of power plant is 150 鈩，

本文编号：1990692