Purpose

This paper aims to clarify the corrosion inhibition effect of different corrosion inhibitor systems on the corrosion of metal pipe string by potassium persulfate plugging agent, so as to improve the injection capacity of polymer plugging well and reduce the corrosion of steel by oxidant plugging agent.

Design/methodology/approach

The effect of different corrosion inhibitors on the corrosion inhibition of N80 carbon steel in 1% potassium persulfate solution was studied by electrochemical experiment and weight loss experiment. The corrosion inhibition mechanism of potassium persulfate inhibitor and the synergistic mechanism among different inhibitors were analyzed.

Findings

The results indicated that when the temperature was 50°C, the inhibition effect of 0.2% sodium molybdate with a single inhibitor was the best at pH 8.5, and the inhibition rate was 70.17%. The inhibition efficiency of 0.2% sodium molybdate + 0.3% sodium silicate in the composite inhibition system can reach 94.38%. In the temperature range of 20°C–60°C, with the increase of system temperature, the inhibition effect of corrosion inhibitor will gradually weaken.

Originality/value

The corrosion inhibition system of N80 steel in potassium persulfate oxidant was mainly studied, and it clarified the influence of temperature and pH value on the corrosion inhibition effect, which provided guidance and suggestions for the corrosion inhibition of tubular string in the oilfield.

中文翻译：

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过硫酸钾注入堵聚合物井缓蚀剂体系

目的

本文旨在阐明不同缓蚀剂体系对过硫酸钾堵剂对金属管柱腐蚀的缓蚀作用，以提高聚合物堵井的注入能力，减少氧化剂堵剂对钢的腐蚀。

设计/方法/方法

通过电化学实验和失重实验研究了不同缓蚀剂对N80碳钢在1%过硫酸钾溶液中缓蚀作用的影响。分析了过硫酸钾缓蚀剂的缓蚀机理及不同缓蚀剂间的协同作用机理。

发现

结果表明，当温度为50℃时，0.2%钼酸钠与单一抑制剂的缓蚀效果在pH 8.5时效果最好，缓蚀率为70.17%。0.2%钼酸钠+0.3%硅酸钠在复合缓蚀体系中缓蚀效率可达94.38%。在20℃～60℃的温度范围内，随着系统温度的升高，缓蚀剂的缓蚀作用逐渐减弱。

原创性/价值

主要研究了N80钢在过硫酸钾氧化剂中的缓蚀体系，阐明了温度和pH值对缓蚀效果的影响，为油田管柱缓蚀提供了指导和建议。