摘要
保温层进水,会造成层下金属的腐蚀。对玻璃棉、141 b体系聚氨酯泡沫塑料、二氧化硅气凝胶保温毡浸出液和去离子水的pH值、电导率、离子浓度进行了测试,对其腐蚀性进行分析,为保温材料的选用和腐蚀控制提供参考。实验结果表明:玻璃棉浸出液呈弱碱性,电导率是三种材料中最大的,并随着浸泡时间和浸泡温度的增加有增大的趋势,浸出液中含有Ca^(2+)、CO_3^(2-)、SO_4^(2-)和Cl^-,易引起点蚀、外应力腐蚀开裂; 141 b体系聚氨酯泡沫浸出液呈弱碱性,pH值随着浸泡时间和浸泡温度的增长有减小的趋势,电导率相对较小,80℃浸出液电导率大于常温浸出液,浸出液中未检出SO_4^(2-)、CO_3^(2-);二氧化硅气凝胶保温毡浸出液呈中性,随浸泡时间和温度的增加转变成酸性,电导率随浸泡时间和浸泡温度的变化不大,浸出液中未检出SO2-4、CO_3^(2-)。与去离子水中Cl^-浓度相比,141 b体系聚氨酯泡沫塑料、二氧化硅气凝胶保温毡浸出液中Cl^-浓度接近0 mg/L。
Corrosion under insulation happened when water came into thermal insulation layer.The pH value,conductivity and ions contents of aqueous extracts of glass wool,141 b system polyurethane foam and silica aerogel insulation blankets and deionized water were tested to estimate their corrosivity and provide references for thermal insulation materials selection and corrosion control.The results showed that the lixivium of glass wool was alkalescent.Its conductivity was the largest among the three and increased with the soaking duration and temperature rising.It contained Ca 2+,CO 2-3,SO 2-4 and Cl-,which easily caused pitting corrosion and external stress corrosion cracking.The lixivium of 141 b system polyurethane foam was alkalescent,the pH value of which decreased with the soaking duration and temperature rising.The conductivity was relatively smaller and that of 80℃lixivium was larger than lixivium under room temperature.SO 2-4 and CO 2-3 weren t detected in the lixivium.The lixivium of silica aerogel insulation blankets was neutral and changed into acid with soaking duration and temperature increasing.The conductivity changed slightly with soaking duration and temperature variation.SO 2-4 and CO 2-3 weren t detected either.Compared with the deionized water,the concentration of Cl-in lixivium of 141 b system polyurethane foam and silica aerogel insulation blankets was closed to 0 mg/L.
作者
蒋林林
张彦军
张红磊
周冰
韩文礼
Jiang Linlin;Zhang Yanjun;Zhang Honglei;Zhou Bing;Han Wenli(CNPC Engineering Technology Research Limited Company,Tianjin,300451,China;The Key Laboratory of Tubular Goods Engineering,CNPC-Research Division of Anti-Corrosion Coatingand Thermal Insulation Structure,Tianjin,300451,China)
出处
《天然气与石油》
2018年第5期80-85,共6页
Natural Gas and Oil
关键词
保温材料
浸出液
腐蚀性
分析
Thermal insulation materials
Aqueous extract
Corrosivity
Analysis
