L320原油输送管道静置段的腐蚀机理

Corrosion Mechanism of the Stationary Section of L320 Crude Oil Pipeline

选取某腐蚀穿孔L320输油管道静置段作为研究对象,通过现场调研、理化检验和电化学方法等方法,研究了原油输送管道静置段的腐蚀原因。结果表明,原油输送管道静置段的服役环境主要为含H2S、CO2、矿化物的油水混合介质,腐蚀失效主要集中在管道内壁的5~7点钟部位,腐蚀产物呈疏松状,含有S、O、C、Fe元素,失效的主导因素为含H2S与CO2的原油沉积水引起的局部腐蚀。此外,疏松状的腐蚀产物有加速腐蚀的作用,腐蚀形态也由局部腐蚀转变为均匀腐蚀。

The static section of a corrosion perforat ed L320oil pipeline was selected as the researc h object.The corrosion causes of the stationary section of t he crude oil pipeline were studied through fiel d investigation,physical and chemical testing and electrochemical method s.The results show that the service environment of the stationary section of the crude oil pipeline was mainly oi l-water mixed medium containing H2S,CO2and mine ral compounds. Corrosion failure was mainly concentrated on th e 5to 7o'clock position on the inner wall of th e pipeline.The corrosion product was loose and contained S,O,C ,and Fe elements.The dominant factor of failure was localized corrosion caused by crude oil deposited water c ontaining H2S and CO2.In addition,the loose cor rosion products had the effect of accelerating corrosion,and the co rrosion morphology was also changed from locali zed corrosion to uniform corrosion.