锅炉管内腐蚀结垢过程的实验研究

Experimental Study of the Corrosion and Fouling Process In Boiler Tubes

管内腐蚀结垢是影响锅炉安全运行的主要因素之一,为了研究高温高压下锅炉管内的腐蚀结垢过程,在一定工况下进行挂片实验,利用SEM,EDS,XRD等分析手段,结合称重法,得出以下结论:金属表面的腐蚀结垢层分3层,依次为:氧化层、中间层、结垢层;腐蚀结垢过程也分为3个阶段:氧化膜形成期,结垢迅速成长期,稳定期;浓度的增加会促进金属的腐蚀和结垢速率;表面粗糙度增加对腐蚀的影响不大,但会促进结垢。

The corrosion and fouling in tubes is one of main factors influencing the safe operation of a boiler.To study the corrosion and fouling process in boiler tubes at a high temperature and pressure,a plate-hanging test was performed under a certain operating condition.By making use of the SEM(scanning electron microscope),EDS(energy spectrum analysis) and XRD(X-ray diffractometer) etc.analytic means and in combination with the weighing method,the authors have arrived at the following conclusions:the corrosion and fouling layer on metallic surfaces is divided into three layers,namely,oxidation,intermediate and fouling layer in turn.The corrosion and fouling process is also divided into three phases: oxide film formation period,fouling fast growth period and stabilization period.An increase of the concentration can promote the corrosion and fouling speed of metals.An increase of the roughness has little influence on the corrosion but can accelerate the fouling.