高流速、高盐、高CO_(2)湿气条件下X60管线钢顶部的腐蚀行为

Top of Line Corrosion Behavior of X60 Pipeline Steel in CO_(2) Wet Gas Environment with High Cl-Concentration and High Gas Flow Rate

为明确X60管线钢在高流速、高含盐、高含CO_(2)湿气条件下的顶部腐蚀行为和规律,采用高速湿气环路系统对X60管线钢进行湿气顶部腐蚀模拟评价试验。通过腐蚀前后试样的失重量评估X60管线钢湿气顶部腐蚀的情况,并采用扫描电子显微镜(SEM)、能谱分析(EDS)以及X射线衍射仪(XRD)等测试分析手段,研究了不同含水率和不同Cl-浓度对X60管线钢湿气顶部腐蚀行为的影响。结果表明:在1 MPa CO_(2)、气体流速10 m/s、Cl^(-)含量分别为130000,170150 mg/L,含水率分别为0.03%和0.05%的工况下,X60管线钢试样表面均有结晶盐粒分布,即在较长服役周期下存在结垢风险。在Cl^(-)含量为130000 mg/L时,高含水率能促进X60管线钢的腐蚀;当Cl^(-)含量增至170150 mg/L时,含水率的升高反而抑制X60管线钢的顶部腐蚀。

To clarify the top of line corrosion behavior of X60 pipeline steel at high CO_(2) wet gas and high flow rate condition with high Cl-,high speed wet gas loop system was used to conduct wet gas top of line corrosion simulation evaluation test of X60 pipeline steel.The wet top of line corrosion of X60 pipeline steel was evaluated by weight loss of samples before and after corrosion.The effects of different water content and different Cl-concentration on the wet top of line corrosion behavior of X60 pipeline steel were studied by means of scanning electron microscope(SEM),energy dispersive spectroscopy(EDS)and X-ray diffraction(XRD).Results showed that the salt particles were observed on the surface of X60 pipeline steel samples,indicating that there was scaling risk in a long service life under the conditions of 1 MPa CO_(2),10 m/s wet gas flow rate condition with 130000 mg/L and 170150 mg/L Cl^(-),water content of 0.03%and 0.05%.When the Cl^(-) content was 130000 mg/L,the high water content promoted the corrosion of X60 pipeline steel.When the Cl^(-) content reached 170150 mg/L,the corrosion weight loss of X60 pipeline steel decreased with the increasing of water content.