原油沉积水对Q235B碳钢的腐蚀影响  

Corrosion Behaviour of Q235B Carbon Steel in Sediment Water From Crude Oil

作　　者：程庆利[1,2] 陶彬[1] 刘栓[3] 刘全桢[1] 张卫华[1] 田松柏[2] 王立平[3] 

机构地区：[1]中国石化青岛安全工程研究院,青岛266071 [2]中国石化石油化工科学研究院,北京100083 [3]中国科学院宁波材料技术与工程研究所,宁波315201

出　　处：《中国腐蚀与防护学报》2017年第2期126-134,共9页Journal of Chinese Society For Corrosion and Protection

基　　金：中国石化安全工程研究院资金(Y-199和Y-200);国家自然科学基金(41506098);中国博士后基金和第九批特等(2015M580528和2016T90553);宁波市自然科学基金(2016A610261)~~

摘　　要：采用电化学阻抗、丝束电极、SEM/EDS和XRD的分析方法,研究原油沉积水对Q235B碳钢腐蚀行为的影响。结果表明,碳钢在沉积水中浸泡21 d过程中,腐蚀速率逐渐降低,腐蚀形式以均匀腐蚀为主;而从21~35 d浸泡过程中,碳钢的腐蚀速率逐渐增大,且腐蚀程度加剧,腐蚀形态由均匀腐蚀为主转变为以点蚀为主的局部腐蚀,点蚀的大小和密集度增加。这是由于在起始阶段,碳钢表面沉积一层CaCO_3,有效地阻碍了腐蚀,而随着时间的延长,CaCO_3逐渐失去对碳钢基体的保护,从而加速局部腐蚀的发生。With the increasing import of high-sulfur oils, the storage tank bottom plates suffer severe corrosion from sediment water, which often cause the leakage of crude oil and result in serious economic loss and environmental pollution. The corrosion behavior of Q235B carbon steel in sediment water from crude oil was investigated by means of electrochemical impedance spectroscopy, wire beam electrode, electrochemical measurements and SEM/XRD techniques. Results showed that during the initial immer- sion period of 21 d the carbon steel suffered from uniform corrosion and its corrosion rate decreased with time. Afterwards, the corrosion was transformed to localized corrosion and its corrosion rate increased with time during the period of 21-35 d of immersion. The fact can be explained that the carbon steel surface was covered by scale of CaCO3, and the corrosion process can be hindered. However, corrosion pits were initiated and accelerated with increasing of time due to loss of corrosion protection from CaCO3 deposits after 21 d.

关 键 词：原油沉积水 Q235B碳钢 腐蚀 丝束电极 

分 类 号：TG172[金属学及工艺—金属表面处理]