高含盐量酸性油水混合液对弯管处管线的腐蚀研究  

Perforation corrosion of high salinity acidic water-oil mixture on the pipeline

作　　者：刘宇程[1] 张寅龙[1] 陈明燕[1] 

机构地区：[1]西南石油大学化学化工学院,成都610500

出　　处：《安全与环境学报》2014年第6期35-38,共4页Journal of Safety and Environment

摘　　要：吐哈油田输油管线弯管处频繁发生腐蚀泄漏事故,容易产生安全隐患,造成环境污染,需要针对现场腐蚀情况分析弯管泄漏原因。对管道中的油水混合液和管材进行成分检测,分析油水混合液中可能的腐蚀物质,核查管材质量是否符合国家标准GB/T 699—1999《优质碳素结构钢》,通过扫描电镜(SEM)观察腐蚀产物的微观形貌,分析弯管处流体的流动状态对腐蚀的影响,通过腐蚀产物颜色观察、EDS元素分析和XRD衍射波谱研究了腐蚀产物的组成,结合腐蚀产物的微观形貌和结构组成分析弯管的腐蚀原因。结果表明,在H2S的作用下,弯管处腐蚀产物主要为Fe S0.9,有少量的Fe S0.9被介质汇总的溶解O2氧化成S单质和Fe3O4,腐蚀产物膜呈漩涡状,并伴有微弱开裂,由于弯管处压力和动能增大并伴有强烈的二次涡流,金属表面难以附着地层砂、腐蚀产物(Fe S0.9、Fe3O4和S单质)和腐蚀垢(Ca CO3),腐蚀介质不断与新的管壁层接触,造成腐蚀加速。对于这种腐蚀情况,建议使用对油水混合液在涡流状态有针对性的H2S缓蚀剂、管材或涂层进行有效的弯管腐蚀防护。This paper aims at introducing our research results on the perforation corrosion effect of high salinity acidic water-oil mixture on the life-span of the pipeline. For our research purpose, we have chosen the accidents of corrosion and leakage that took place frequently at the elbow of the petroleum transmission pipeline in Tuba Oilfield as case study sample. In order to make clear the actual situation of the corrosion of the elbow, we have first of all analyzed the chemical composition of the petroleum transmission pipeline inhoping to make a comparison of the corrupted pipeline to the national standard of Quality Carbon Structural Steels （GB/T 699--1999） and carefully examined the mixture of the oil and water to make clear the likely corrosion-leading products. In so doing, we have first of all studied the effect of the current state of the oil - water mixture on the corrosion of the elbow by means of the microscopic morphology of the corrosion products via Electronic Scanning Microscope （ESM）. In the process of our study of the corrosion situation, the corrosion products were tested and measured in view of their outlook, their Energy Dis- perse Spectroscopy （ EDS）, and the X-ray Diffraction （XRD） as well. In addition, we have also made an effort in identifying the cor- rosion causes in view of the microscopic morphology of the corrosion film and the chemical composition of the corrosion products. The resuits of our exploration can be shown as follows： the corrosion products at the elbow were mainly found made up of FeSo.9, S and Fe304, which has been formed as the result of oxidation of FeSo.9. The corrosion film has taken on the form of vortex with a slight cracking. And, the increase of the oil-water mix pressure and kinetic energy, in addi- tion to the strong secondary vortex at the elbow, it has been difficult to remove the formation sand, the corrosion products （FeSo.9, Fe304 and S）, as well as the corrosion scale （CaCO3） sticking to the metal surface of the pipe. And, in turn, t

关 键 词：安全工程 弯管腐蚀 输油管道 高含盐 H2S 原因分析 

分 类 号：X937[环境科学与工程—安全科学]