Electrochemical study on the corrosion rate of X52 steel exposed to different soils

Abstract

Purpose The purpose of this work is to study the corrosion rate of X52 pipeline steel exposed to three types of soils collected in Campeche State in México. The electrochemical evaluation for X52 steel exposed to soils ranging from saturated soil until dry conditions was carried out for a period of 21 days. Owing to its versatility to study the steel corrosion process exposed to different types of soils, electrochemical impedance spectroscopy (EIS), potentiodynamic polarization and cyclic voltammetry tests were performed. Additionally, optical and electronic microscopy observations of the steel surface were carried out. Design/methodology/approach Electrochemical cell arrangement was described elsewhere (Quej-Ake et al., 2014). Owing to soil being an electrolytic system with high resistivity and impedance, all electrodes were placed as close as possible, and iR-drop compensation was taken into account using two rods of graphite as an auxiliary electrode. In addition, the conductivity of the soil (Rs) obtained from EIS was used to correct the potential of the working electrode according to iR-drop, and an analysis of ohmic drop from the polarization curves was carried out. Findings Saturated conditions of the three soils were initially considered as the most corrosive conditions for X52 steel surface. Finally, 21 days of immersion time was taken into account as the more drastic condition. So, according to results, X52 steel exposed to beach sand was more susceptible to the corrosion process (0.092 mm/year). iR corrected was negligible at low over-potentials region in saturated soils, which is inside the linear region of Tafel or the activation region. In addition, high cathodic peak potential value obtained from cyclic voltammetry for X52 steel exposed to saturated soil may be attributed to hydrogen evolution reaction and neutral pH. Research limitations/implications The paper has implications for research. It bridges the gap between theory and practice. Originality/value Cyclic voltammetry is a really important tool for the electrochemical analysis of the pipeline steel surface exposed to saturated soils, but is not adequate for analysis of steel exposed to dried soils. In addition, the physicochemical results show that fissures, voids and extra-oxygen presence could also affect the electrochemical responses obtained for X52 steel exposed to soils.

Weak impact of underground water on corrosion inhibition of resistance-reducing agent

“…Thus, the corrosion rate was significantly lower in the RRA without underground water infiltration. The physical and chemical properties of soil affect the corrosion behavior of carbon steel (Quej-Ake and Contreras, 2018). With the underground water infiltration, the increase of Cl − content will lead to the decrease in ( R ct + R f ) −1 while causing an increase in corrosion current density and corrosion rate (Zhu et al , 2020).…”

Review on Soil Corrosion and Protection of Grounding Grids

“…Moisture in the soil acts as an electrolyte, providing an environment conducive to the formation of corrosion cells. In addition, alterations in moisture content profoundly impact the physical and chemical properties of the soil, thereby influencing the corrosion tendencies observed in grounding grids [21,42,43]. Noor and Al-Moubaraki [44] investigated the corrosion rate of X60 steel under different water-content conditions.…”

Microbiologically influenced corrosion: a review of the studies conducted on buried pipelines

“…The last system used are soil samples, conducted with buried coupons in the ground, with soil samples in recreated conditions outdoors (Norhazilan et al 2012) or by taking soil samples into the laboratory and use specialized test cells developed by individual research groups (Dafter 2011;Goodman et al 2013;Hendi et al 2018;Li et al 2003;Mineta 2018;Olivares et al 2003;Quej-Ake and Contreras 2018;Sun et al 2011;Yu 2018;Zhao et al 2007). Each of these types of tests has its limitations, especially when MIC is considered.…”