超超临界机组锅炉受热面氧化皮堆积原因分析与防范措施

Cause Analysis and Preventive Measures of Oxide Scale Accumulation on Heating Surface of Ultra Supercritical Unit Boiler

火力发电厂炉管氧化皮脱落堆积引起的管子堵塞,是目前超超临界机组锅炉爆管的主要原因。参考某电厂运行约45,000小时的1000 MW超超临界机组氧化皮堆积检测结果,发现使用TP347H的低温再热器管氧化皮堆积尤其严重。根据炉管氧化皮形成和脱落的原理,建议对炉管进行酸洗,并在后期的运行中选择合适的运行温度,减小氧化皮的生成速率,避免氧化皮脱落堆积造成堵管。

At present, the main reason for the tube explosion of ultra supercritical unit boilers is the tube blockage caused by the falling off and accumulation of oxide skin of boiler tubes in thermal power plants. Referring to the test results of oxide scale accumulation of 1000MW Ultra Supercritical Units operating for about 45000 hours in a power plant, it is found that the oxide scale accumulation of low temperature reheater tubes using TP347H is particularly serious. According to the principle of the formation and falling off of the oxide skin of the furnace tube, it is recommended to pickle the furnace tube and select the appropriate operating temperature in the later operation to reduce the generation rate of the oxide skin and avoid the pipe blockage caused by the falling off and accumulation of the oxide skin.