土壤含水率和氯离子含量对最佳保护电位的影响  

Influence of Moisture and Chloride Ion Content in Soil on Optimal Cathodic Protection Potential for X70 Steel

作　　者：李自力[1] 王太源[1] 郝宏娜[1] 杜松林[1] 崔淦[1] 

机构地区：[1]中国石油大学(华东)储运工程系,青岛266555

出　　处：《腐蚀科学与防护技术》2012年第3期232-235,共4页Corrosion Science and Protection Technology

基　　金：国家科技重大专项大型油气田及煤层气开发项目(2008Z-X05017-04-01)资助

摘　　要：利用电化学阻抗谱技术,研究X70钢的最佳阴极保护电位随土壤中Cl-和含水率的变化.结果表明:在Cl-含量<10 mmol/kg时最佳保护电位随着含水率的增加先升高后降低,变化幅度在150 mV左右;Cl-含量≥10 mmol/kg时,最佳保护电位随着含水率增加呈现降低的趋势;Cl-含量为20 mmol/kg时的不同含水率的土壤中最佳保护电位均达到最小值;随着含水率的升高Cl-对最佳保护电位的影响逐渐减小.The relationship of moisture and chloride ion content in Qingdao soil with the opti- mum cathodic protection potential for X70 steel was studied by electrochemical impedance spectroscopy （EIS）in a laboratory test set. The results revealed that the optimum cathodic protection potential increased firstly, then reduced with the increase of moisture content when chloride ion was less than 10 mmol/kg with a potential fluctuation about 150 mV. When the chloride ion is greater than 10 mmol/kg, the optimal protection potential showed a trend of reducing with increasing moisture content. The optimal cathodic protection potential in soil with various moisture contents reached a minimum for chloride ion content of 20 mmol/kg. With the rise of moisture content, the influence of chloride ion decreased gradually.

关 键 词：电化学阻抗谱 最佳保护电位 阴极保护参数 含水率 氯离子 

分 类 号：TE988[石油与天然气工程—石油机械设备]