摘要
采用高温高压釜研究了X52管线钢在高含量H_2S/CO_2(60℃、pH_2S=1.5 MPa、pCO_2=0.9 MPa)共存环境中的腐蚀特性,以及Cl-和元素硫对其腐蚀行为的影响,并结合SEM和XRD对腐蚀产物膜、表面形貌和腐蚀产物成分进行分析。结果表明,在高含量H_2S/CO_2共存环境中,X52钢的腐蚀产物主要为马基诺矿和硫铁矿,腐蚀受H_2S控制,且以均匀腐蚀为主,表面腐蚀产物膜对X52钢的全面腐蚀有一定的抑制作用,但不能防止氢鼓泡;X52钢的腐蚀速率随Cl^-含量的升高先增大后减小,腐蚀产物的晶化度明显降低,保护性差;X52钢的腐蚀速率随元素硫含量的增加先增大后减小,在硫含量为5g/L时,其腐蚀速率最大,为14.70mm/a。硫含量过大时,易发生聚结沉积,使腐蚀速率有所下降。
The corrosion characteristics of X52 pipeline steel in aqueous solution with 1.5 MPa H2S and 0.9 MPa CO2 at 60 ℃,and the effects of Cl^-and element sulfur on the corrosion were investigated by high-temperature and high-pressure autoclaves,and the surface morphology and composition of corrosion product were studied by SEM and XRD methods.The results showed that the main corrosion products of X52 in the H2S/CO2 environment were mackinawite and troilite,the corrosion was controlled by H2S and dominated by uniform corrosion.The surface corrosion product film had a certain inhibitory effect on the general corrosion of X52 steel,but could not prevent hydrogen blisters. The corrosion rate of X52 first increased and then decreased with the increase of Clconcentration,the protectiveness of the corrosion product was poor due to the obvious reduction of the product crystallization degree.The effect of elemental sulfur was similar to that of Cl^-ions,and the corrosion rate was up to14.70mm/a when the content of elemental sulfur was 5g/L.Elemental sulfur was prone to deposition when its content was too large,resulting in the decrease of corrosion rate.
出处
《腐蚀与防护》
CAS
北大核心
2015年第12期1166-1169,1189,共5页
Corrosion & Protection
基金
中石化科研项目(308057)
