Menu
Search
Filters
Close
Menu

Effect of Solution pH on Corrosion Product Layer Formation in a Controlled Water Chemistry System

Picture for Effect of Solution pH on Corrosion Product Layer Formation in a Controlled Water Chemistry System
Available for download

The primary objective of this study was to investigate iron carbonate (FeCO3) formation mechanisms on ferritic-pearlitic carbon steel corroding in a CO2 saturated aqueous solution near iron carbonate saturation, with particular emphasis on the effect of solution pH.

Product Number: 51317--9160-SG
ISBN: 9160 2017 CP
Author: Supat IEAMSUPAPONG
Publication Date: 2017
Industry: Science of Corrosion
$0.00
$20.00
$20.00

Most CO2 corrosion experiments are conducted at high levels of supersaturation with respect to iron carbonate in a glass cell. This leads to more rapid attainment of steady state with respect to corrosion rate and corrosion product formation. However most operating conditions in an upstream pipeline do not match with these ‘easily tested’ conditions. To better simulate internal pipeline environments found in field conditions a flow-through system was used to control the water chemistry by maintaining saturation values with respect to iron carbonate for the entire testing time. All experiments were conducted on UNS G10180 mild steel at 80?C pCO2 of 0.53 bar and velocity of 0.6 m/s in 1wt.% NaCl electrolyte within a pH range of 5.4-6.0. The evolution of the corrosion process was continuously monitored by electrochemical methods. Scanning electron microscopy (SEM/EDS) was used as the main characterization tool to study the corrosion product layers on the surface and in cross-section. It was found that similar corrosion product layers and corrosion rates are observed in pH range of 5.4-6.0. The ending corrosion rates indicate that the higher solution pH tends to give slightly better protection to the steel surface. Under the controlled water chemistry the lower solution pH condition needs a thicker Fe3C layer which acts as diffusion boundary layer in order have high enough “intrasurface” pH to nucleate FeCO3.Keywords: solution pH controlled water chemistry flow-through system Fe3C FeCO3

Key words: Solution pH, Controlled water chemistry, FeCO3; Carbon steel

Most CO2 corrosion experiments are conducted at high levels of supersaturation with respect to iron carbonate in a glass cell. This leads to more rapid attainment of steady state with respect to corrosion rate and corrosion product formation. However most operating conditions in an upstream pipeline do not match with these ‘easily tested’ conditions. To better simulate internal pipeline environments found in field conditions a flow-through system was used to control the water chemistry by maintaining saturation values with respect to iron carbonate for the entire testing time. All experiments were conducted on UNS G10180 mild steel at 80?C pCO2 of 0.53 bar and velocity of 0.6 m/s in 1wt.% NaCl electrolyte within a pH range of 5.4-6.0. The evolution of the corrosion process was continuously monitored by electrochemical methods. Scanning electron microscopy (SEM/EDS) was used as the main characterization tool to study the corrosion product layers on the surface and in cross-section. It was found that similar corrosion product layers and corrosion rates are observed in pH range of 5.4-6.0. The ending corrosion rates indicate that the higher solution pH tends to give slightly better protection to the steel surface. Under the controlled water chemistry the lower solution pH condition needs a thicker Fe3C layer which acts as diffusion boundary layer in order have high enough “intrasurface” pH to nucleate FeCO3.Keywords: solution pH controlled water chemistry flow-through system Fe3C FeCO3

Key words: Solution pH, Controlled water chemistry, FeCO3; Carbon steel

Product tags
Also Purchased
Picture for Effect of pH on CO2 Corrosion at Elevated Temperatures
Available for download

51313-02348-Effect of pH on CO2 Corrosion at Elevated Temperatures

Product Number: 51313-02348-SG
ISBN: 02348 2013 CP
Author: Tanaporn Tanupabrungsun
Publication Date: 2013
$20.00
Picture for Elemental Sulfur and Speciation in High Pressure High Temperatures Oil and Gas Well Environments: Th
Available for download

Elemental Sulfur and Speciation in High Pressure High Temperatures Oil and Gas Well Environments: Their Role in Stress Corrosion Cracking of Corrosion Resistant Alloys

Product Number: 51317--9035-SG
ISBN: 9035 2017 CP
Author: Yuhchae Yoon
Publication Date: 2017
$20.00

This paper reviews both available stress corrosion cracking data and test methodologies involving additions of elemental sulfur using several procedures. It utilizes thermodynamic modeling to assess the chemical speciation of elemental sulfur under selected test conditions.
Picture for Enhanced Corrosion Prediction Model for Multiphase Oil and Gas Production Systems
Available for download

Enhanced Corrosion Prediction Model for Multiphase Oil and Gas Production Systems

Product Number: 51317--9419-SG
ISBN: 9419 2017 CP
Author: Hui Li
Publication Date: 2017
$20.00

A top-of-line corrosion (TLC) model integrated into a CO2/H2S corrosion prediction model. The TLC model determines the top of the line corrosion rate of carbon steel based on water chemistry and film-wise condensation rate. The effect of various glycols, such as Monoethylene Glycol, Diethylene glycol and Triethylene Glycol, are included.
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