Studying High Temperature And High Pressure Corrosion And Scale Inhibitors In Water Injection Wellbore

In oilfield, water injection is the effective means for keeping formation pressure andimproving oil production rate,which is widely used at home and abroad. So the oilfieldsewage treatment and reinjection is becoming more and more attention. Corrosion and scalingare one of the most serious problems in the process of oilfield waste water treatment andreinjection, especially under the condition of high temperature and high pressure in thewellbore. The most promising measure is to choose appropriate scale inhibitors and corrosioninhibitors.This topic studies high temperature and high pressure corrosion and scale inhibitorsbased on a lot of literature and the actual investigation.This topic researches domestic and international oilfield technology of corrosion andscaling in the oilfield injection wells. finding out the domestic and international status quo ofscale and corrosion protection, investigating corrosion and scaling on-site in BinWu sewagestation in Shengli oilfield. By analysisng injection water quality in BinWu sewage station, themain corrosion reason is carbon dioxide, bacteria, high salinity and dirt in tube wall in BinWuinjection water system. Injection Water goes back to the injection Wells along the waterinjection process, due to changes of the environment and corrosion of the water injectionsystem, water quality further deteriorates, and corrosion resistance enhances.Scanning scalesamples in BinWu sewage station with electron microscopy and energy spectrum, the mainreason is high salinity and high calcium ion. Reserch injection water in BinWu sewage station,make a detailed investigation of effect to prevent corrosion and scale formation with addingcorrosion and scale inhibitor, study the types and performance of corrosion and scale inhibitor.First of all, under the condition of high temperature and normal pressure, using staticweight-loss method, electrochemical method and static scale inhibition test screen scale and corrosion inhibitor that have good performance, and then using the autoclave dynamicexperimental method test whether the corrosion and scale inhibitor at high temperature meetthe requirements. Finally through optimizing formula, select the best drug and dosing quantity.The experimental results show that, for the P110, adding the corrosion and scale inhibitordosing is mi1227/HGY-H (90:70mg/L), the average corrosion rate reduced from0.0391mm/a to0.0033mm/a, anti-scaling rate was97.2%. For N80, adding the corrosion scaleinhibitor dosing is mi1227/HGY-H (80:70mg/L), the average corrosion rate reduced from0.0391mm/a to0.0031mm/a, the anti-scaling rate is95.5%. The water injection system hasobtained the very good anticorrosion and descaling effect, and has obvious economicbenefits.