超临界机组的合金管蒸汽侧氧化膜生长与剥落研究进展  

Review on the Oxide Growth and Exfoliation on Alloy Tube from Supercritical Power Plant

作　　者：徐洪[1] 祁晶 XU Hong;QI Jing(Jiangsu Frontier Electric Technology Co.,Ltd.,Nanjing,China,Post Code:211102;School of Energy and Mechanical Engineering,Nanjing Normal University,Nanjing,China,Post Code:210046)

机构地区：[1]江苏方天电力技术有限公司,江苏南京211102 [2]南京师范大学能源与机械工程学院,江苏南京210046

出　　处：《热能动力工程》2022年第2期1-7,共7页Journal of Engineering for Thermal Energy and Power

摘　　要：超临界机组高温合金管氧化膜剥落问题是困扰机组安全与经济运行的难题,严重制约了机组蒸汽参数和效率的提高。特别是,在超临界机组采用给水加氧处理方式(OT)后,奥氏体不锈钢管内壁氧化膜大面积剥落事故屡见不鲜,尤以TP347H合金管为甚。本文总结了近年来国内外针对超临界机组合金管氧化膜研究的进展及相关成果,首先介绍了超临界蒸汽环境中合金管氧化机理和原子迁移机制,综述了铁素体和奥氏体合金表面氧化膜的形貌特征,分析了蒸汽溶氧对氧化膜生长速率、形貌和缺陷的影响。氧化膜完整性是决定合金抗腐蚀性能的重要因素,但在机组运行过程中氧化膜应力破坏了氧化膜完整性。进一步总结了国内外氧化膜应力和剥落研究的数值分析及实验研究情况,为我国超临界机组氧化膜剥落故障诊断研究提供参考。The problem generated by oxide scale formed on superheater alloy tubes in supercritical power plant confuses the safety and economic operation,which seriously restricts the improvement of the steam parameters and efficiency of power plant.The supercritical units adopt the feed water oxygenation treatment(OT),which could cause large area exfoliation accident on the oxide scale formed on the inner surface of austenite stainless steel tubes,especially in TP347 H alloy tube.This paper reviews the process and related achievements for oxide scale formed on alloy tubes in supercritical power plant at home and abroad in recent years.Firstly,the oxidation mechanism and atomic migration mechanism of alloy tube in supercritical steam environment are introduced.The morphology characteristics of oxide scale on the surfaces of ferrite and austenite alloys are reviewed.The effects of steam dissolved oxygen on the growth rate,morphology and defects of the oxide scale are analyzed.The integrity of oxide scale has an important effect on the corrosion resistance of alloy.The integrity of oxide scale is damaged by the oxide stress during the operation of the unit.This paper further summarizes the numerical analysis and experimental studies on the stress and exfoliation of oxide scale,and provides reference for the research on the spalling exfoliation fault diagnosis of oxide scale in supercritical units.

关 键 词：超临界机组 氧化膜生长 氧化膜剥落 锅炉 给水加氧 

分 类 号：TK221[动力工程及工程热物理—动力机械及工程]