TY  - JOUR
AB  - Purpose The salinity of the oilfield produced water has a significant effect on steel corrosion. The purpose of this paper is to study the influence of salinity on corrosion behavior of X60 steel and it also provides basic for material selection of gas wells with high salinity.Design/methodology/approach The weight loss experiment was carried out on steel with high temperature and high pressure autoclave. The surface morphology and composition of corrosion scales were studied by means of scanning electron microscopy, energy dispersive spectroscopy and X-ray diffractometry.Findings The results show that as salinity increases, the corrosion rate of X60 steel will gradually experience a rapid decline stage and then a slow decline stage. X60 steel is mainly exhibiting uniform corrosion in the first rapid decline stage and pitting corrosion in the second slow decline stage. The increase in salinity reduces gas solubility, which, in turn, changes the morphology and density of the corrosion scales of X60 steel. At low salinity, loose iron oxides generated on the surface of the steel, which poorly protects the substrate. At high salinity, surface of the steel gradually forms protective films. Chloride ions in the saline solution mainly affect the structure of the corrosion scales and initiate pitting corrosion. The increased chloride ions lead to more pitting pits on the surface of steel. The recrystallization of FeCO3 in pitting pits causes the corrosion scales to bulge.Originality/value The investigation determined the critical concentration of pitting corrosion and uniform corrosion of X60 steel, and the new corrosion mechanism model was presented.
VL  - 67
IS  - 2
SN  - 0003-5599
DO  - 10.1108/ACMM-06-2019-2147
UR  - https://doi.org/10.1108/ACMM-06-2019-2147
AU  - Dong BaoJun
AU  - Liu Wei
AU  - Wu Fei
AU  - Zhu JiaQi
AU  - Wongpat Banthukul
AU  - Zhao Yonggang
AU  - Fan Yueming
AU  - Zhang TianYi
PY  - 2020
Y1  - 2020/01/01
TI  - Determination of critical salinity of pitting and uniform corrosion of X60 under CO2-O2 coexistence environment
T2  - Anti-Corrosion Methods and Materials
PB  - Emerald Publishing Limited
SP  - 166
EP  - 177
Y2  - 2024/04/20
ER  -