摘要
烟气经选择性催化还原(SCR)脱硝后,产生的硫酸氢铵会造成空气预热器(空预器)冷端蓄热元件腐蚀和堵塞。将三分仓回转式空预器转子看成多孔介质,建立了非热平衡模型,模拟得出某600 MW机组空预器工质和受热面三维温度分布,分析了烟风出口温度和受热面转子温度沿旋转方向的变化规律。结果表明:烟气沿流动方向温度逐渐降低,空气沿流动方向温度逐渐升高,出口温度沿旋转方向几乎呈线性关系,且由于分仓的存在,沿旋转方向各个分仓的交界面上温度是不连续的;蓄热元件温度从热端到冷端逐渐降低,沿旋转方向呈先增后减的趋势;低温腐蚀危险区域主要集中在冷段,硫酸氢铵沉积危险区域主要集中在冷段和热段交界处。
After the flue gas is denitrated by selective catalytic reduction(SCR)denitration system,the ammonium bisulfate(ABS)will cause corrosion and blockage of the heat storage elements at cold end of the air preheater.By regarding the tri-sectional rotary air preheater rotor as a porous medium,three-dimensional numerical simulation of the air preheater and the heating surface of a 600 MW unit is carried out by using the non-thermal equilibrium model.The temperature of the exhaust gas and the changing law of the rotor temperature at heating surface along the rotation direction are analyzed.The results show that,the temperature of the flue gas gradually decreases along the flow direction,while that of the air increases along the flow direction.The outlet temperature is almost linear with the rotation direction,and the temperature is discontinuous in the interface of each storehouse along the rotation direction due to the existence of the storehouse.The temperature of the heat storage elements decreases gradually from the hot end to the cold end,and along the rotation direction it increases at first and then decreases.The dangerous area of low-temperature corrosion is mainly concentrated in cold section,and the dangerous area ofABS deposition is mainly concentrated at the junction of cold section and hot section.
作者
闫顺林
曹保鑫
YAN Shunlin;CAO Baoxin(School of Energy Power and Mechanical Engineering,North China Electric Power University,Baoding 071003,China)
出处
《热力发电》
CAS
北大核心
2020年第4期51-57,共7页
Thermal Power Generation
关键词
三分仓
回转式空气预热器
多孔介质
非热平衡模型
硫酸氢铵沉积
腐蚀
堵塞
tri-sectional
rotary air preheater
porous medium
non-thermal equilibrium model
ammonium bisulfate decomposition
corrosion
blockage
