低温烟气条件下三维肋管积灰腐蚀特性的实验研究

Experimental Research on Ash Deposition and Corrosion Characteristics of 3-D Finned Tube Under Low Temperature Flue Gas

本文开展了三维肋管在低温含尘含酸烟气条件下的积灰腐蚀特性实验,对不同工况下三维肋管腐蚀积灰形貌、酸沉积率及积灰量的变化规律进行了研究,揭示了三维肋管低温含尘烟气条件下的腐蚀机理,获得了积灰腐蚀规律。发现在冷却水进口温度和硫酸体积分数变化时,三维肋管迎风面主要发生析氢腐蚀,背风面主要发生吸氧腐蚀;降低冷却水进口温度,肋管表面酸沉积率先增大后减小,积灰量逐渐增大;增大酸体积分数,肋管表面酸沉积率上升,积灰量逐渐增加。

In this paper,the ash deposition corrosion characteristics of 3-D finned tube in low-temperature dust and acid flue gas were studied.The change rules of ash deposition morphology,acid deposition rate and ash deposition amount of 3-D finned tube in different working conditions were studied.The corrosion mechanism of 3-D finned tube in low-temperature dusty flue gas was revealed,and the ash deposition corrosion law was obtained.It was found that with the change of cooling water inlet temperature and sulfuric acid volume fraction,hydrogen evolution corrosion mainly occured on the windward side and oxygen absorption corrosion mainly occured on the leeward side of the 3-D finned tube.With the decrease of cooling water inlet temperature,the acid deposition on the surface of the finned tube first increased and then decreased,and the ash deposition gradually increased.With the increase of acid volume fraction,the acid deposition rate on the surface of the finned tube increased,and the ash deposition gradually increased.