Corrosion Factors of Water Injection System in Shuanghe Oil Treatment Station

Corrosion control is important to the purified produced-water as injection-water. The corrosion factors of injection water system were analyzed in Shuanghe oil treatment station with the static analysis method. The effects of inorganic ions, ion interaction, dissolved oxygen, pH and temperature of wastewater on corrosion rate were discussed. The results showed that the corrosion rate order per unit cationic ions was Na+＜Ca2+＜Mg2+＜Fe2+＜Fe3+; that per unit anion ion was SO42-＜HCO3—＜S2-. The corrosion rate increased with increasing the dissolved oxygen concentration. The major influence factors of corrosion rate were Fe3+and S2- under the conditions considering dissolved oxygen, pH and temperature to produced-water. The average corrosion rate decreased from 0.1262 mm/a to 0.055 mm/a after anti-corrosion measures were implemented.