HCl-H_2S-H_2O体系中HCl与H_2S对20碳钢腐蚀的交互作用

Interactive Effect of Hydrochloric Acid and Hydrogen Sulfide in Water on Corrosion of Plain Carbon Steel

目前有关HCl-H2S-H2O体系中HCl与H2S对碳钢腐蚀的交互作用的试验数据较少。利用电化学方法测试了20碳钢在90℃,不同浓度的HCl,H2S单一腐蚀液及HCl和H2S混合腐蚀液中的腐蚀速率,分析了HCl-H2S-H2O体系中HCl与H2S对20碳钢腐蚀的交互作用。结果表明:20碳钢在单一的HCl或H2S腐蚀液中的腐蚀速率随HCl或H2S浓度的增大而增大;在HCl-H2S-H2O体系中,不论H2S浓度高低,HCl的存在均会促进H2S对20碳钢的腐蚀;只有当HCl的浓度较低(≤248.72 mg/L)时,H2S的存在才会促进HCl对20碳钢的腐蚀;而当HCl浓度较高(≥499.16 mg/L)时,H2S的存在不仅不会促进HCl对20碳钢的腐蚀,还会在一定程度上起阻碍作用。

The corrosion rates of 20 steel in water (90 ℃) containing different concentration of HCl or H2S single-component corrosive agent as well as HCl-H2S mixed corrosive agent were measured with an electrochemical method. The interactive effect of HCl and H 2 S on the corrosion of the carbon steel was investigated. Results indicated that,in HCl-H2S-H2O medium, HCl accelerated the corrosion of the carbon steel whether high or low concentration of H2S was present. However,H 2 S did not accelerate the corrosion of the carbon steel unless a low concentration (≤248. 72 mg/L) of HCl was present; and it even could inhibit the corrosion of the carbon steel to some extent in the presence of a high concentration (≥499. 16 mg/L) of HCl.