Optimization Of Corrosion Inhibitor For Oxidation And Plug Remo Val Fluid Of Polymer Injection Wells In Jinzhou 93 Block

Strong oxidizer is widely used in petrochemical industry,and it is often used as the main component of plug remo Ver and fracturing fluid with remarkable effect.Howe Ver,the corrosion caused by strong oxidant is one of the main reasons for the damage or e Ven in Validation of production and transportation equipment,resulting in huge economic losses and e Ven safety accidents.In recent years,the problem of formation plugging has appeared in Jinzhou 93 block after polymer flooding,which needs to be sol Ved.And most of the methods of adding corrosion inhibitor to inhibit the corrosion of metal ha Ve the characteristics of high efficiency,en Vironmental protection and low cost,which is a research field of considerable industrial Value.And most of the researches on corrosion inhibitors are about the corrosion of metals by HCl,Na Cl,etc,and few on the strong oxidants.Therefore,in order to protect the en Vironment and reduce resource consumption,it is of great significance to study the strong oxidants.N80 carbon steel is taken as the research object.Through the electrochemical method for polarization cur Ve,impedance spectrum and equi Valent circuit analysis,weight loss method,micro experiment and quantum chemistry,the inhibition effects of single inhibitor and compound inhibitor on N80 carbon steel in 2% potassium persulfate solution at 50℃were studied.Meanwhile,The effects of temperature and p H of the system on the inhibition effect of each inhibitor were studied too.At the same time,the mechanism of corrosion inhibitors is analyzed from the electrochemical and microscopic point of View,and the synergistic mechanism among the inhibitors is analyzed.Finally,a more economical,en Vironmental friendly and efficient inhibitor is found.For a single inhibitor,0.2% sodium molybdate has the best corrosion inhibition effect at 50℃,which corrosion inhibition rate is 80%.After mixture of 0.1% sodium molybdate and 0.2% sodium silicate has the most practical significance and economic Value,and the corrosion inhibition efficiency reaches 96%.It was also founded that with the increase of the system temperature,the inhibition effect of the inhibitor will gradually weaken,and a small decrease of the system p H will make the inhibition effect of the inhibitor better,but a larger decrease of the p H will intensify the corrosion.