全面腐蚀控制
全麵腐蝕控製
전면부식공제
Total Corrosion Control
2015年
9期
61-63
,共3页
烟气%废热锅炉%腐蚀%管束%露点
煙氣%廢熱鍋爐%腐蝕%管束%露點
연기%폐열과로%부식%관속%로점
exhaust gas%waste heat boiler%corrosion%heat exchange tube%dew point
分析了二催化装置烟气能量回收系统废热锅炉管束腐蚀泄漏的原因.现场腐蚀调查结果表明,废热锅炉的腐蚀主要集中在烟气侧第一排换热管的水平段,特别是折流墙附近换热管束腐蚀最为严重.废热锅炉烟气侧的腐蚀机理为硫酸露点腐蚀,受炉墙砌筑稀料和烟气侧积水的影响,折流墙处换热管束表面温度低于硫酸露点温度,烟气中的SO 3与水蒸气相结合形成硫酸蒸汽在该部位换热管表面凝结,形成硫酸露点腐蚀导致管束穿孔泄漏.最后,针对废热锅炉的腐蚀原因,提出了废热锅炉折流墙结构改造、投用前烘炉、按设计要求施工等消除烟气中硫酸露点腐蚀的防护措施.
分析瞭二催化裝置煙氣能量迴收繫統廢熱鍋爐管束腐蝕洩漏的原因.現場腐蝕調查結果錶明,廢熱鍋爐的腐蝕主要集中在煙氣側第一排換熱管的水平段,特彆是摺流牆附近換熱管束腐蝕最為嚴重.廢熱鍋爐煙氣側的腐蝕機理為硫痠露點腐蝕,受爐牆砌築稀料和煙氣側積水的影響,摺流牆處換熱管束錶麵溫度低于硫痠露點溫度,煙氣中的SO 3與水蒸氣相結閤形成硫痠蒸汽在該部位換熱管錶麵凝結,形成硫痠露點腐蝕導緻管束穿孔洩漏.最後,針對廢熱鍋爐的腐蝕原因,提齣瞭廢熱鍋爐摺流牆結構改造、投用前烘爐、按設計要求施工等消除煙氣中硫痠露點腐蝕的防護措施.
분석료이최화장치연기능량회수계통폐열과로관속부식설루적원인.현장부식조사결과표명,폐열과로적부식주요집중재연기측제일배환열관적수평단,특별시절류장부근환열관속부식최위엄중.폐열과로연기측적부식궤리위류산로점부식,수로장체축희료화연기측적수적영향,절류장처환열관속표면온도저우류산로점온도,연기중적SO 3여수증기상결합형성류산증기재해부위환열관표면응결,형성류산로점부식도치관속천공설루.최후,침대폐열과로적부식원인,제출료폐열과로절류장결구개조、투용전홍로、안설계요구시공등소제연기중류산로점부식적방호조시.
The corrosion leakage cause of waste heat boiler tube bundle forflue gas energy recovery system was analyzed in II FCC unit.Field survey results show that the corrosion of waste heat boiler mainly concentrated in theflue gas side of thefirst row in the level of the heat pipe section, especially the corrosion of heat exchange tube bundle is most serious near the baffle wall. And the corrosion mechanism of waste heat boiler for flue gas side was sulfuric acid dew point corrosion, under the influence of the furnace wall thinner and water offlue gas side,surface temperature of heat exchange tube bundle was lower than the sulfuric acid dew point temperature. SoSO3 and steam formed sulfuric acid vapor, and led to a bundle perforation leakage. Finally, in view of the waste heat boiler corrosion reasons, some protection measures were put forward,such as baffle wall structure transformation, oven before use,and constructing according to the design requirements.