Menu
Search
Filters
Close
Menu

Celebrate World Corrosion Awareness Day with 20% off eCourses and eBooks with code WCAD2024 at checkout!

Electrochemical Investigation Into the Influence of Monoethylene Glycol on CO2 Corrosion in the Presence of Acetic Acid

Picture for Electrochemical Investigation Into the Influence of Monoethylene Glycol on CO2 Corrosion in the Presence of Acetic Acid
Available for download
Product Number: 51321-16332-SG
Author: Md Mayeedul Islam/Rolf Gubner/Thunyaluk Pojtanabuntoeng
Publication Date: 2021
$0.00
$20.00
$20.00

This study aims to i) determine the dissociation constant (pKa) of acetic acid (HAc) in monoethylene glycol (MEG) which is used to calculate the relative amount of undissociated HAc at different pH, and ii) investigate the influence of MEG on CO2 corrosion of carbon steel in the presence of HAc. The study reveals that MEG increases the pKa of HAc and obstructs its dissociation. The later effect is remarkable at pH 5 and greater. MEG also hinders the galvanic effect of ferrite and cementite by adsorbing on the active sites and reduce the corrosion rate. The inhibition efficiency of MEG is strongly dependent on its concentration. HAc is found to aggravate the corrosion of carbon steel but its activity considerably reduces with increasing MEG concentration.

Keywords: Monoethylene glycol; dissociation constant; CO2 corrosion; acetic acid; desorption potential

This study aims to i) determine the dissociation constant (pKa) of acetic acid (HAc) in monoethylene glycol (MEG) which is used to calculate the relative amount of undissociated HAc at different pH, and ii) investigate the influence of MEG on CO2 corrosion of carbon steel in the presence of HAc. The study reveals that MEG increases the pKa of HAc and obstructs its dissociation. The later effect is remarkable at pH 5 and greater. MEG also hinders the galvanic effect of ferrite and cementite by adsorbing on the active sites and reduce the corrosion rate. The inhibition efficiency of MEG is strongly dependent on its concentration. HAc is found to aggravate the corrosion of carbon steel but its activity considerably reduces with increasing MEG concentration.

Keywords: Monoethylene glycol; dissociation constant; CO2 corrosion; acetic acid; desorption potential

Product tags
Also Purchased
Picture for Laboratory Investigation of Biocide Treated Waters to Inhibit Biofilm Growth and Reduce the Potential for MIC
Available for download

Laboratory Investigation of Biocide Treated Waters to Inhibit Biofilm Growth and Reduce the Potential for MIC

Product Number: 51321-16209-SG
Author: Susmitha Purnima Kotu/Christopher Kagarise/Richard B. Eckert/Torben Lund Skovhus
Publication Date: 2021
$20.00
Picture for The Determination of the Chloride Threshold of Stainless Steel in Concrete – A Review
Available for download

The Determination of the Chloride Threshold of Stainless Steel in Concrete – A Review

Product Number: 51321-16179-SG
Author: Sylvia Kessler
Publication Date: 2021
$20.00
Picture for Study on Glycol Reboiler and Surge Vessel Corrosion in Glycol Regeneration Unit
Available for download

Study on Glycol Reboiler and Surge Vessel Corrosion in Glycol Regeneration Unit

Product Number: 51319-13289-SG
Author: Ali Akrouf
Publication Date: 2019
$20.00

Glycol systems are widely used in gas processing plants for the removal of contaminants such as moisture from the gas. Since the majority of the piping and vessels in these plants are fabricated from carbon steel there is a high potential for corrosion. This paper provides a brief overview of some of the major corrosion mechanisms associated with Glycol regeneration unit. In addition a case study from a Try-Ethylene Glycol (TEG) regeneration system is also discussed where localized corrosion was noticed in the Glycol reboiler and surge vessel. Booster Station facility receives gas from Gathering Center for further compression and removes moisture before being exported to the refinery. This is achieved by compression of gas in multiple stages with locally provided compression equipment and processed in glycol dehydration units to remove the moisture. Water vapor removal from the gas stream is achieved by contacting the wet gas counter-currently with lean (dry) TEG in the glycol contactor column. The rich glycol having water content is routed through a pre-heating coil flash tank filters and finally comes in the Glycol reboiler. Due to the high temperature in reboiler the glycol loses its ability to hold water. Separated water is vaporized and leaves through top of the still column. The regenerated glycol flows to the surge tank and from there it is pumped to Glycol absorber. During one of the Plant Maintenance shutdowns Glycol reboiler and surge vessel were opened for internal inspection and appreciable corrosion was noticed in the top sections of the vessels. A study was initiated to find out the probable causes of the deterioration. Corrosion products were collected for XRD analyses. Also chemical analysis of lean & rich Glycol samples taken from various streams was carried out. A corrosion pattern was established along the glycol regeneration circuit which revealed mainly the low pH of Rich Glycol due to possible decomposition reaction of glycol into organic acid. Presence of Iron sulfate and various forms of iron sulfide including Pyrite Greigite and Pyrhotite (also referred to as Black Powder Derivatives) all known to expedite localized corrosion and deterioration of the metals. This paper presents the findings based on the analysis of the corrosion products and glycol samples and discusses the possible corrosion mechanisms. Recommendations are also provided to ensure the integrity and reliability of these vessels for sustainable operation. This case history demonstrates the diverse nature of the causes of Glycol related corrosion in plants and the differing approaches that have to be taken to mitigate corrosion in Glycol regeneration equipment.
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