Adding System Optimisation of Corrosion Inhibitor in Oil Producer in CoFlooding Field Test

Abstract CO2 corrosion is one of the key factors that restrain CO2 flooding. Corrosion damage by CO2 breakthrough and water content increase has greatly influence the regular production of oil field. To protect the casing pipe, tubing, sucker rod and deep well pump entirely, inhibitor control technology which uses chemical method as the principal method is needed. At present, filling inhibitor into the casing-tubing annular is used for anti-corrosion, however, adding rests can be influenced by many factors. According to varied environment of CO2 flooding oil field and the study of inhibitor property and residual concentration, a weak-absorption film former inhibitor used in the CO2 flooding well has been chosen by the lab test evaluation and field experience; dosing concentration, dosing circle and dosing method also have been optimized. All of these works help establish a reasonable inhibitor filling system, as well as improve the dosing efficiency and the pertinence of anti-CO2 corrosion. After being injected in the CO2 flooding well, the inhibitor caused effect of decreasing corrosion damage, as well as reducing the cost. According to the corrosion monitoring and residual concentration test, when the corrosion ratio is lower than 0.076mm/a, there will be no corrosion in the well bore and the downhole tools. This comprehensive anti-corrosion method can meet the field needs. Keywords: anti-CO2 corrosion, inhibitor, dosing method, dosing circle