超（超）临界机组锅炉受热天面高温硫腐蚀与磨损防护技术研究.docVIP

第47卷 第1期 2002年1月 简 报 PAGE - PAGE 1 - 超（超）临界机组锅炉受热面高温硫腐蚀与磨损防护技术研究 李太江，李巍，李勇，刘立营，王博 西安热工研究院有限公司，陕西省西安市兴庆路136号 710032； Study on the Protective Techniques for the Heating Face of Super-Ultra Critical Unit from High Temperature Sulfur Corrosion and Erosion LI Tai-jiang, LI Wei, LI Yong, LIU Li-ying, WANG Bo Xi’an Thermal Power Research Institute Co., Ltd., Xi’an, 710049, China; 第47卷 第1期 2002年1月 简 报 PAGE ABSTRACT: In view of the situation of shutting down for repairing due to the leakage and tube cracking caused by severe high temperature sulfur corrosion, solid-particle erosion and wear, high velocity oxygen fuel (HVOF) was employed to deposit NiCr cermet coatings on 2Cr13 substrates. The anti-sulfur corrosion behavior of the NiCr cermet coating and 2Cr13 substrate was studied in an atmosphere with high sulfur content. The anti-erosion behavior of the NiCr cermet coating and 2Cr13 was also studied. The results indicated that the sealed NiCr cermet coating deposited by HVOF can reduce the high temperature corrosion and erosion rate. The 8000 hours in-field application of the NiCr cermet coating shows its effectivity to protect the heating surface tube in super-ultra critical unit fired with of high-sulfur coal from high temperature sulfur corrosion and erosion. KEYWORDS: Ultra supercritical unit; Sulfur corrosion; Solid particle erosion; HVOF; NiCr cermet coating 摘要：针对燃用高硫煤的超（超）临界机组锅炉受热面遭受高温硫腐蚀与磨蚀导致泄漏、爆管等事故而被迫停炉检修的情况，本文采用了超音速火焰喷涂NiCr金属陶瓷涂层，比较了相同腐蚀环境下涂层与抗腐蚀性能较高的2Cr13基体的高温硫腐蚀性能，同时比较了该涂层与2Cr13基体钢材的抗磨损性能。研究结果表明超音速火焰喷涂的NiCr金属陶瓷涂层具有比2Cr13钢更优的抗高温硫腐蚀性能。同时其抗高温磨损性能优于2Cr13钢。该超音速火焰喷涂NiCr金属陶瓷涂层在贵州某燃用高硫煤的电厂中经8000小时现场挂片考核后，涂层表面完好，可有效提高超（超）临界机组的抗高温硫腐蚀和磨损性能。 关键词：超(超)临界机组；高温硫腐蚀；磨损；超音速火焰喷涂；NiCr金属陶瓷涂层 1前言 目前，超（超）临界机组已经成为国内新建和扩建机组的主要发展趋势，其主汽压力和温度高，可大大提高机组热效率和经济性，是我国电力行业的主力机组[1-3]。但随着电煤供应趋于紧张，劣质燃煤的掺烧比例不断加大，超超临界机组锅炉“四管”(水冷壁管、过热器管、再热器管、省煤器管)将遭受严重磨损和高温硫腐蚀[4-7]。在我国贵州、四川等地的电厂多用当地的煤种，有的煤矿硫含量高达4～6%以上，洗选后含硫量仍然高达2～4%，使燃用这种高硫煤的机组锅炉受热面发生严重的高温硫腐蚀，这种高温硫腐蚀与煤粉对受热面的冲蚀磨损共同作用，相互影响，导致锅炉