高硫重馏分油对碳钢的腐蚀  

Carbon Steel Corrosion in High-Sulfur Crude Distillates

作　　者：牛鲁娜 张超 兰正贵[1] 韩磊[1] 屈定荣[1] IU Luna;ZHANG Chao;LAN Zhenggui;HAN Lei;QU Dingrong(Qingdao Safety Engineering Institute,SINOPEC,Qingdao 266000,China;Petrochemical Engineering Co.Ltd.,CNOOC,Qingdao 266000,China)

机构地区：[1]中国石化青岛安全工程研究院,山东青岛266000 [2]中海油石化工程有限公司,山东青岛266000

出　　处：《石油学报（石油加工）》2019年第4期730-735,共6页Acta Petrolei Sinica(Petroleum Processing Section)

摘　　要：结合化学反应机理分析,采用电位滴定法和质谱法分别测定了高硫重馏分油中的总活性硫含量、硫化物的类型和分布,并模拟高温侧线实际工况,开展了20^#钢和16MnR钢等2种典型碳钢材质在重馏分油中的腐蚀行为研究,利用挂片法、扫描电镜和XRD等手段对腐蚀试样进行了腐蚀速率分析、腐蚀形貌观察和腐蚀产物组成分析。结果表明,高硫重馏分油中硫化物以噻吩类的非活性硫为主,活性硫所占总硫的比例均不足1%。在实验环境下,20^#钢和16MnR钢发生高温硫腐蚀,生成的FeS腐蚀产物膜松散,附着力较差,对基体不能起到良好的保护作用。20^#钢和16MnR钢的耐蚀性相近,随着介质中硫含量增加,腐蚀速率随之增加,但实验腐蚀速率均明显低于采用修正的McConomy曲线估算的理论腐蚀速率。根据研究结果,将McConomy方法获得的理论腐蚀速率进行校正,为指导企业合理选材,制定检维修计划提供支持。Corrosion behaviors and corrosion reaction mechanisms of two typical carbon steels in crude distillates were studied under the conditions of simulated high temperature distillate sidelines.Total active sulfur content in the distillates were determined by potentiometric titration.Composition and distribution of sulfur compounds were further characterized by mass spectrometry.Corrosion rate,corrosion topography and corrosion product composition were investigated through weight-loss method,scanning electron microscope (SEM) and X-Ray diffraction (XRD),correspondingly.Experimental results show that,sulfur compounds with thiophene rings are dominant in the high-sulfur heavy distillates,and the proportion of active sulfur in total sulfur is less than 1%.Under the experimental environment,both 20^# steel and 16MnR steel have high-temperature sulfur corrosion,and the FeS corrosion product is loose and has poor adhesive capability.This kind of FeS film is easy to be flushed off and could not play a good protective role.It was found that the corrosion rates of 20^# steel and 16MnR steel are similar with each other.Corrosion rate for carbon steel increases with sulfur contents,however,experimental corrosion rates are significantly less than McConomy theoretical rates.Based on experimental results,a modified method to predict theoretical corrosion rates has been established to support industrial metallurgy selection and maintenance.

关 键 词：腐蚀 硫化物 活性硫 馏分油 碳钢 

分 类 号：TE986[石油与天然气工程—石油机械设备]