好氧细菌降低油田采出水对管钢腐蚀的研究

运用Tafel曲线、线性极化曲线和电化学阻抗谱(EIS)等电化学技术研究了序批式间歇反应器(SBR)中嗜油好氧细菌对J55油套管钢在油田采出水中腐蚀行为的影响,并利用扫描电镜(SEM)和X-射线衍射(XRD)分析了腐蚀膜的形貌和成分,采用失重法测量了动态腐蚀速率.结果表明,嗜油好氧细菌加入后,J55油套管钢试样表面所成腐蚀膜的组分发生了变化,腐蚀膜的致密性增强,膜与钢基体之间的结合力增大;好氧细菌的加入显著降低了J55钢在采出水中的腐蚀速率,有菌条件下的腐蚀速率是无菌条件下的40%.此外,还对嗜油好氧菌减缓J55油套管钢在油田采出水中腐蚀速率的机理进行了分析.

Influence of aerobic bacteria on corrosion inhibition of oil bushing steel in the oilfield stratum water

The influences of aerobic bacteria on corrosion behaviors of oil bushing steel J55 in the stratum water were investigated by Tafel plots, linear polarization curves and the electrochemical impedance spectroscopy (EIS). The microstructure and composition of the corrosion scale formed on the J55 steel were analyzed by scanning electron microscopy (SEM) and X-ray diffraction (XRD). The scale composition changed, the scale compactness enhanced and the adherence between the substrate and the corrosion scale increased with the addition of the aerobic bacteria. The experimental results of electrochemical corrosion rate indicated that the bacteria could significantly decrease the corrosion rate of the J55steel by 60% in the oilfield stratum water. The mechanism of corrosion inhibition of oil bushing steel J55 by aerobic bacteria in the oilfield stratum water was discussed.