摘要
水媒管式烟气换热器(MGGH)是锅炉烟气超低排放处理系统的重要组成部分,其运行环境恶劣,换热管腐蚀机理复杂,解决换热管低温腐蚀是一项关键难题。通过换热管腐蚀机理分析,表明MGGH烟气再热器低温段处于第Ⅱ腐蚀严重区。对比提出2种控制低温腐蚀速率工程技术手段,满足要求的换热管材质为316L、DIN1.4529、包塑管和搪瓷管,通过研究、比选,发现选用搪瓷换热管可满足工程要求。从耐硫酸腐蚀能力、热传导性能、材料机械性能、防冲刷抗磨损能力以及工程造价等方面论证,搪瓷换热管有优异的耐低温腐蚀、抗磨损和热传导性能,且传热效果优于钢管,能很好地解决换热管低温腐蚀问题,具有重要的工程推广价值。
The water medium heat pipe gas-gas heater （MGGH） is an important part of ultra-low flue gas emission technology for coal-fired boilers, of which the operating environment is bad and the corrosion mechanism of the heat exchange tube is complex, it is a key problem to solve the low temperature corrosion of heat exchange tube.Analysis on corrosive mechanism of the heat exchange tube shows that the low temperature section of the gas reheater in the MGGH is located on the No.II serious corrosion zone. There are two engineering techniques to control the low temperature corrosion rate and the heat exchanger tube materials of 316L, DIN1.4529, plastic and enamel can satisfy the requirement. It finds that the enamel heat exchange tube can meet the engineering requirements through the research and comparison. From several aspects such as the corrosion resistance of sulfuric acid, thermal conductivity, mechanical properties of materials, anti erosion ＆ abrasion resistance and engineering cost, the enamel heat exchange tube can solve the problem of low temperature corrosion. Enamel heat exchange tube has excellent performance of low temperature corrosion resistance, wear resistance and heat conduction, and the capability of heat transfer is superior to the steel pipe. It has been verified that the enamel heat exchange tube can satisfy the technical requirement, and has important engineering application by engineering practice.
出处
《热力发电》
CAS
北大核心
2017年第9期130-134,共5页
Thermal Power Generation
基金
浙江省自然科学基金项目(LYl5E060002)~~
关键词
搪瓷
换热管
低温腐蚀
烟气换热器
超低排放
酸露点
防腐
enamel, heat exchange tube, low temperature corrosion, gas-gas heater, ultra-low flue gas emission, sulfuric acid dew point, corrosion protection
