油田地面油水混输管线腐蚀影响因素分析

Corrosion Factor Analysis of Oil-water Mixed Transportation Pipelines in Oilfield Ground

吕乃欣 刘开平 高 燕 郭 刚 庞永莉

Lü Naixin LIU Kaiping GAO Yan GUO Gang PANG Yongli

为获得油田采出污水与管材材质对油田地面油水混输管线腐蚀行为的影响规律， 通过测定按不同标准生 产的碳钢和不锈钢在 33个区块采出污水中的腐蚀速率， 结合统计分析软件 SPSS的分析结果， 研究了污水中 S 2- 含量、 pH值、 矿化度以及管材材质等因素与钢材腐蚀速率之间的相关性。结果表明， 碳钢类材质化学成分含量 相近， 碳钢类材质之间腐蚀速率的相关系数均大于 0.945， 呈显著正相关关系， 几种碳钢类材质在油田污水中的 耐蚀性差异较小； 不锈钢类材质含有 Cr、 Ni等合金元素， 耐蚀性能大大增强。油田污水中 S 2-含量对碳钢类材质 的腐蚀影响较大， 随污水中 S 2-浓度增加， 碳钢类材质的腐蚀速率先增加后降低， S 2-为 68 mg/L时碳钢达到最大腐 蚀速率 0.1823 mm/a； 污水中 S 2-含量小于 70 mg/L 时， S 2-与碳钢类材质腐蚀速率呈现显著正相关， 相关系数 0.523， 概率 （P）为 0.003。采出污水 pH值和矿化度对碳钢腐蚀的影响较小， 污水 pH值和矿化度与碳钢腐蚀速率 的相关系数分别为 0.238、 0.130， P分别为 0.182、 0.468， 存在相关性但影响有限。图3表 6参17

In order to study the effect of oilfield produced water and pipeline material on the corrosion of oil-water mixed transportation pipelines in oilfield ground， the correlation between S2- content， pH value and salinity of sewage， pipeline material and the corrosion rate of steel was analyzed by measuring the corrosion rate of carbon steel produced by different standards and stainless steel in produced water of 33 blocks， and combining with the statistical analysis software SPSS. The results showed that the chemical composition of carbon steels was similar. The correlation coefficient of corrosion rates between carbon steel materials was greater than 0.945， showing a significant positive correlation. The corrosion resistance differences of several kinds of carbon steel in oilfield produced water were small. Because of the alloy elements Cr and Ni， the corrosion resistance of stainless steel material was greatly enhanced. The content of S2- in oilfield produced water had a great influence on the corrosion of carbon steel. With the increase of S2- concentration in oilfield produced water， the corrosion rate of carbon steel increased first and then decreased. When the dosage of S2- was 68 mg/L， the carbon steel had the maximum corrosion rate（0.1823 mm/a） . When the dosage of S2- in sewage was less than 70 mg/L， S2- had a significant positive correlation with corrosion rate of carbon steel which correlation coefficient was 0.523 and the probability（P）was 0.003. The pH value and salinity of sewage had a little influence on the corrosion of carbon steel.The correlation index between pH value and salinity of sewage and corrosion rate of carbon steel was 0.238 and 0.130， and the probability（P）was 0.182 and 0.468 respectively， showing a limited correlation to corrosion