Menu
Search
Filters
Close
Menu

03327 The Effect of Cl - and Acetic Acid on Localized CO2 Corrosion in Wet Gas Flow

Picture for 03327 The Effect of Cl - and Acetic Acid on
Available for download
Product Number: 51300-03327-SG
ISBN: 03327 2003 CP
Author: Yuhua Sun, Keith George, Srdjan Nesic
$0.00
$20.00
$20.00
Wet gas corrosion rates of C1018 and X65 steel have been measured at the top and bottom of a high pressure, 10 cm diameter horizontal pipeline under stratified flow conditions with different chloride (Cl - ) concentrations. Experiments were performed for 200 hours at 90°C, CO2 partial pressure of 3.8 bar using a superficial gas velocity (Vsg) of 10 m/s and a superficial liquid velocity (Vsl) of 0.1 m/s. Three measurement techniques; ER, LPR, and WL were used simultaneously in the experiments. Localized corrosion occurred at the bottom of the pipe around the iron saturation point. The top of line was well protected by a thin corrosion product film and no localized corrosion was detected. C1018 and X65 have different sensitivities to pitting with a variation in Cl - concentration. Thus the pitting density concept is proposed to describe localized corrosion behavior. Surface analysis on iron carbonate films, by SEM and XRD, revealed different film thicknesses and crystal structures from the top to the bottom of the pipe. Cross-sectional analysis indicates that the thin corrosion product film, usually less than 10 microns, attached to the metal surface, is responsible for the low corrosion rate on top of the line, while the thick and porous film formed on the bottom, generally detached from the metal surface, was responsible for the initiation of localized corrosion. Before adding acetic acid (HAc) to the flow loop, a systematic glass cell test program was initiated using potentiodynamic sweeps to investigate the electrochemical properties of carbon dioxide corrosion in the presence of HAc. A standard rotating cylinder three-electrode setup was employed. Tests were performed to study the effect of HAc in solutions de-oxygenated using both nitrogen and carbon dioxide. The range of HAc concentrations was then expanded to study the effect of the concentration of HAc on the cathodic and anodic reactions in carbon dioxide solutions. The presence of HAc was found to not affect the corrosion rate of carbon steel at low temperature since the main cathodic reaction (hydrogen ion reduction) was found to be under charge transfer control. The limiting current was strongly affected by the HAc concentrations, but the charge transfer mechanism was not changed. The anodic reaction was retarded with increasing HAc concentrations but the mechanism stayed the same. The effect of pH, temperature and rotational velocity was also studied. Key words: C1018 steel, X-65 steel, wet gas, localized corrosion, stratified flow, cross section, surface analysis, pitting density, super-saturation, acetic acid, potentiodynamic sweeps
Wet gas corrosion rates of C1018 and X65 steel have been measured at the top and bottom of a high pressure, 10 cm diameter horizontal pipeline under stratified flow conditions with different chloride (Cl - ) concentrations. Experiments were performed for 200 hours at 90°C, CO2 partial pressure of 3.8 bar using a superficial gas velocity (Vsg) of 10 m/s and a superficial liquid velocity (Vsl) of 0.1 m/s. Three measurement techniques; ER, LPR, and WL were used simultaneously in the experiments. Localized corrosion occurred at the bottom of the pipe around the iron saturation point. The top of line was well protected by a thin corrosion product film and no localized corrosion was detected. C1018 and X65 have different sensitivities to pitting with a variation in Cl - concentration. Thus the pitting density concept is proposed to describe localized corrosion behavior. Surface analysis on iron carbonate films, by SEM and XRD, revealed different film thicknesses and crystal structures from the top to the bottom of the pipe. Cross-sectional analysis indicates that the thin corrosion product film, usually less than 10 microns, attached to the metal surface, is responsible for the low corrosion rate on top of the line, while the thick and porous film formed on the bottom, generally detached from the metal surface, was responsible for the initiation of localized corrosion. Before adding acetic acid (HAc) to the flow loop, a systematic glass cell test program was initiated using potentiodynamic sweeps to investigate the electrochemical properties of carbon dioxide corrosion in the presence of HAc. A standard rotating cylinder three-electrode setup was employed. Tests were performed to study the effect of HAc in solutions de-oxygenated using both nitrogen and carbon dioxide. The range of HAc concentrations was then expanded to study the effect of the concentration of HAc on the cathodic and anodic reactions in carbon dioxide solutions. The presence of HAc was found to not affect the corrosion rate of carbon steel at low temperature since the main cathodic reaction (hydrogen ion reduction) was found to be under charge transfer control. The limiting current was strongly affected by the HAc concentrations, but the charge transfer mechanism was not changed. The anodic reaction was retarded with increasing HAc concentrations but the mechanism stayed the same. The effect of pH, temperature and rotational velocity was also studied. Key words: C1018 steel, X-65 steel, wet gas, localized corrosion, stratified flow, cross section, surface analysis, pitting density, super-saturation, acetic acid, potentiodynamic sweeps
PRICE BREAKS - The more you buy, the more you save
Quantity
1+
5+
Price
$20.00
$20.00
Product tags
Also Purchased
Picture for 99024 ROLE OF FREE ACETIC ACID ON THE
Available for download

99024 ROLE OF FREE ACETIC ACID ON THE CO2 CORROSION OF STEELS

Product Number: 51300-99024-SG
ISBN: 99024 1999 CP
Author: Jean-Louis Crolet, Nicolas Thevenot, Arne Dugstad
$20.00
Picture for 09292 CO2 Top of the Line Corrosion in Presence of Acetic Acid - a Parametric Study
Available for download

09292 CO2 Top of the Line Corrosion in Presence of Acetic Acid - a Parametric Study

Product Number: 51300-09292-SG
ISBN: 09292 2009 CP
Author: Ziru Zhang, Hongbin (Victor) Wang, Dezra Hinkson, Srdjan Nesic and Marc Singer
Publication Date: 2009
$20.00
Picture for Effect of Acetic Acid on Sour Corrosion of Carbon Steel
Available for download

Effect of Acetic Acid on Sour Corrosion of Carbon Steel

Product Number: 51317--9318-SG
ISBN: 9318 2017 CP
Author: Jon Kvarekval
Publication Date: 2017
$20.00

An experimental study of corrosion of carbon steel in the presence of H2S, CO2 and acetic acid has been carried out. H2S and CO2 partial pressures up to 10 bar each were applied, with temperatures of 25 and 90oC.
Categories
Industry
Recently viewed
Popular tags
View all

Association for Materials Protection and Performance

© AMPP All Rights Reserved.
Membership Terms of Content Use
Contact Customer Support