Iron in Glycol of Dehydration System
Iron in Glycol of Dehydration System
(OP)
Hi All,
I am looking after an offshore gas platform. We recently drained the entire glycol system (due to solids plugging, suspected carbon from the activated carbon filter). We also took sample of the solids and sent for lab analysis. Analysis found that the main constituent was iron. I did a google search and found website below, which says "The typical contaminant is iron oxide which is formed in the circulating glycol system".
My question is, how could iron formed inside TEG glycol? TEG consists of carbon, hydrogen and oxygen. There could be contaminants such as carbon from activated carbon filter, water (of course), possibly silicon from sand, salt, carbon dioxide from gas. But where does the iron come from? My pipings and vessels which the glycol is contained is made from carbon steel, is it suggesting that there could be iron constituents/atoms leaving these structures and react with glycol? I am not quite sure if this would happen, without the presence of oxygen to form rust.
Can anyone enlighten me how would iron be formed in the TEG?
http://www.pall.com/main/fuels-and-chemicals/glyco...
I am looking after an offshore gas platform. We recently drained the entire glycol system (due to solids plugging, suspected carbon from the activated carbon filter). We also took sample of the solids and sent for lab analysis. Analysis found that the main constituent was iron. I did a google search and found website below, which says "The typical contaminant is iron oxide which is formed in the circulating glycol system".
My question is, how could iron formed inside TEG glycol? TEG consists of carbon, hydrogen and oxygen. There could be contaminants such as carbon from activated carbon filter, water (of course), possibly silicon from sand, salt, carbon dioxide from gas. But where does the iron come from? My pipings and vessels which the glycol is contained is made from carbon steel, is it suggesting that there could be iron constituents/atoms leaving these structures and react with glycol? I am not quite sure if this would happen, without the presence of oxygen to form rust.
Can anyone enlighten me how would iron be formed in the TEG?
http://www.pall.com/main/fuels-and-chemicals/glyco...





RE: Iron in Glycol of Dehydration System
RE: Iron in Glycol of Dehydration System
Steve Jones
Corrosion Management Consultant
http://www.linkedin.com/pub/8/83b/b04
All answers are personal opinions only and are in no way connected with any employer.
RE: Iron in Glycol of Dehydration System
Just to enlighten me a bit, since I am not knowledgeable in this area...
If the OP is running a dehydrator with nearly pure TEG, for example, i.e., not a binary solution of TEG + water, will there be water in the glycol? I am thinking that the water, if present, is being picked up by the glycol from the gas stream, and that the corrosion (rust) is on the gas side of the process.
The rationale that the breakdown products of the glycol are acidic, that much I can accept.
RE: Iron in Glycol of Dehydration System
Steve Jones
Corrosion Management Consultant
http://www.linkedin.com/pub/8/83b/b04
All answers are personal opinions only and are in no way connected with any employer.
RE: Iron in Glycol of Dehydration System
I was aware that the rich glycol will have water in it. I just had not realized that (or I have not been exposed to processes in which) the service was especially corrosive in a dehydrator.
Probably haven't done enough acid gas dehydrators in my time.
There have been other discussions of this point in these fora similar to the one attached.
thread338-241467: Material Selection on TEG (Glycol) Dehydrators