纤维素酶对回注水系统管材腐蚀的影响研究

Effect of Cellulase on Corrosion of Pipe Material in Reinjection Water System

以某油田回注水为进水,采用两个平行的玻璃反应器历时56 d对比研究了添加纤维素酶对铸铁试样片腐蚀的影响。试验测定了运行过程中水质的变化,并采用X射线衍射仪和扫描电镜分别分析了腐蚀产物并观察了产物形态。最后,还采用室内动态腐蚀速率和缓蚀率表征了纤维素酶的缓蚀性能,并采用极化曲线法和挂片失重法初步探讨了其缓蚀机理。结果表明:油田回注水是一种具有较强腐蚀趋势的介质,回注水中添加纤维素酶在短期内能减缓铸铁试样片的腐蚀,延缓腐蚀产物晶体形态的出现,改变腐蚀产物的类型;纤维素酶的平均缓蚀率为76.09%,其机理主要是在试样片表面形成吸附膜,且基本满足Langmuir吸附等温式。

Two parallel glass reactors filled with reinjection water of an oilfield were adopted for 56 d to study the effect of cellulase addition on the corrosion of cast iron coupon. The variation in water qual- ity was measured during the experiment. The corrosion product was analyzed by X-ray diffractometer, and its morphology was observed by scanning electron microscopy. In addition, the indoor dynamic corrosion rate and corrosion inhibition rate were used to describe the inhibition characteristics of cellulase while po- larization curve method and weight-loss method were adopted to discuss the corrosion inhibition mecha- nism of cellulase. The results showed that the reinjection water of oilfield was a kind of potent corrosion media and adding cellulase into the reinjection water could slow down the corrosion process of cast iron coupon in a short term, delay the appearance of corrosion product crystal form, and change the type of corrosion products. The average corrosion inhibition rate of cellulase was 76.09%, and the corrosion in- hibition mechanism was the formation of an adsorption film on the surface of coupon with basically obeying the Langmuir adsorption isotherm.