HCl对沸腾流化床燃烧器换热管腐蚀和磨损影响的研究

采用模拟密集颗粒对换热管底部的冲击作用的装置，研究氯化物对埋入燃烧床中管材耗损的影响机制。结果表明ＨＣｌ加剧材料的耗损，其耗损率随温度升高而上升。同时研究磨损表面和腐蚀产物的显微组织化和组成的特征，ＨＣｌ对耗损率的影响主要在于它促进氧化并降低氧化膜的粘附化。

CORROSION-WEAR BEHAVIOR OF IN-BED TUBES DUE TO HCI AND PARTICLES IMPACTS IN A SIMULATED BUBBLING FLUIDIZED BED

Heat-exchanger tubes in fluidized bed combustors (FBCs often suffer from material loss due to combined corrosion and erosion. To further understand the effect of chlorine on in-bed tube wastage, a FBC wastage simulator was used to carry out the study. The later was designed to simulate dense particle impacts on the tube bottoms with well-con- trolled parameters, and has been proven to closely reflect situation found in operation bub- bling FBCs. HCl gas was chosen to be the C1 source and was introduced into the fluidizing air with a dose of 50X Tests were performed at temperatures from ambient to 400'C with samples made of 1018 low carbon steel rods and a bed consisted of commercial SiO sand with average size of 800 pm. The wear profiles after each test was measured using a profilometer. Results showed that the presence of HCl increased the material wastage rates and the rate was significant higher at higher temperatures. The results of microstructural and chemical analysis of the wear surface and corrosion products are also reported. It is concluded that the dominating effect of HCl on the wastage rates is due to an enhanced oxidation and a reduced scale adherence.