正交实验法对20^#碳钢在油田采出水中的应用研究

A research of application of 20^# carbon steel in oilfield water by orthogonal test

为了研究20#碳钢材料在油田上的适用范围,采用室内静态腐蚀挂片正交实验法,模拟油田采出水腐蚀性因素对20#碳钢在油田采出水中的应用进行了探讨。根据腐蚀失重法及试片的腐蚀速率分析,利用正交实验考察ρ(Ca2+)、ρ(HCO3-)、ρ(Cl-)、温度、pH值对20#碳钢腐蚀行为的影响。结果表明,对20#碳钢腐蚀性影响的强弱程度为温度>pH值>ρ(Cl-)>ρ(HCO3-)>ρ(Ca2+)。温度对20#碳钢起主要的影响,其腐蚀速率随温度升高而升高。同时,腐蚀速率随pH值增大而降低。其次,ρ(Cl-)的增加使低碳钢腐蚀加重,ρ(Ca2+)、ρ(HCO3-)对20#碳钢也有一定程度的腐蚀作用。

In order to determine the application scope of 20# carbon steel in the oilfield water,adopting indoor static corrosion hanging orthogonal method,simulating produced water corrosive factors,the application of 20# steel was studied.According to the corrosion of weightlessness and the corrosion rate analysis,using orthogonal method,we investigated the effect of concentration of Cl-,Ca2＋,HCO-3,temperature and pH on corrosion behavior of 20# carbon steel.The results showed that the order of effect on the strength of 20# carbon steel is temperature pHρ（Cl-）ρ（Ca2 ＋）ρ（HCO-3）.20# carbon steel corrosion rate increases with increasing temperature.In oilfield water conditions,the corrosion rate decreases with the increase of pH value.ρ（Cl-）increases corrosion of 20# carbon steel.Ca2＋,HCO-3 also has a certain degree of corrosion damage.