常减压装置常用钢材在高温原油馏分中的腐蚀研究

利用高压釜模拟常减压装置中的腐蚀环境，采用腐蚀失重法并结合SEM，研究了4种常减压装置常用钢材在高温原油馏分中的腐蚀行为，分析了馏分、材质、温度的影响规律。结果表明，原油馏分的酸值、S含量和盐含量越高，对20钢腐蚀性越强，3种原油馏分对20钢的腐蚀性强弱为：脱盐后原油＞常二线馏分＞常一线馏分。提高钢材中Cr，Ni和Mo等合金元素的含量有助于提高其抗腐蚀能力，4种钢材在高温原油馏分中的抗腐蚀性能优劣为：316钢＞304钢＞1Cr5Mo钢＞20钢。温度对钢材在高温原油馏分中的腐蚀行为会产生多方面的影响，腐蚀速率总体上随着温度的升高而增大，某些温度范围内可能出现腐蚀速率极值。

Corrosion Behavior of Steels Used in Making Crude Oil Distillation Unit in High Temperature Crude Oil Fractions

The corrosion behavior of four steels used in making crude oil distillation unit in high temperature crude oil fractions was studied in an autoclave to simulate the corrosive environment in atmospheric and vacuum distillation unit. The mass loss of the samples was measured and then the corrosion morphology was characterized by scanning electron microscopy. The result showed that the higher acid value, sulfur content and salt content of the crude oil resulted in much serious corrosiveness on 20 steel and the corrosiveness of the substances could be ranked as the desalted crude oil > the second atmospheric side-cut fraction > the first atmospheric side-cut fraction. Alloying elements Cr, Ni and Mo could help to improve the corrosion resistance of steels，and the corrosion resistance of the test steels could be ranked as 316 stainless steel > 304 stainless steel > 1Cr5Mo > 20 steel. The overall corrosion rate usually increased with increasing temperature, however, which could reach extreme value in certain range of temperature.