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[shurimano]

What are the common corrosion inhibitors used in TEG Dehydration plants ??

We use MEA if pH value dr below 6.5 to raise pH, during this activity we observed that if we directly dose it to surge drum we see a temperature raise in surge drum of about 6-8 c and colour change - turns into brown and if not filtered properly it turns into slightly black.

If we shock dose the same slowly to lean glycol pump suction there is no temperature rise observed. Although color change is observed.

I understand that by addition of MEA iron is precipitating out and ineffective filtration leads to colour change but I don't get the temperature raise problem issue. Is that because MEA is highly reactive and which is the primary reason for the temp raise ??????

Would like to know what are the corrosion inhibitors options used in other plants, what are the problems they face post addition of corrosion inhibitors to the system and what is the procedure of addition ?? and some more insight to the problem which I stated above will be helpful for my understanding. 

 

[Art Montemayor]

Your post and related questions are difficult to understand - and, as a result, difficult to respond to.

 

First, to my knowledge there are no so-called corrosion inhibitors used in TEG dehydration units - at least certainly not as additives to the TEG.  In 55 years I’ve not heard or read anything related to the subject.  TEG is simply not corrosive and doesn’t form any corrosive reactions with wet or dry natural gas.  You must be processing a corrosive natural gas.  In my opinion adding anything to pure TEG in a natural gas dehydration unit is simply inviting problems and a lot of trouble.

 

What do you mean by “We use MEA if pH value dr below 6.5 to raise pH, during this activity we observed that if we directly dose it to surge drum we see a temperature raise in surge drum of about 6-8”????  Are you adding Monoethanolamine to Triethylene Glycol?   Why would you do that?  Please explain in detail what is certainly not a conventional operation.

 

What kind or type of corrosion are you referring to and where are you witnessing it?  Please do not generalize.  Corrosion is a complex subject because of the many types and origins that it exhibits.  And also be SPECIFIC as to what process system you are experiencing the corrosion in.  Is it a TEG natural gas dehydration contactor tower or the TEG regenration system?  If the regeneration part is undergoing corrosion, where - specifically - is it located?  If you are operating an MEA acid gas or sour gas removal system and having corrosion there, then tells that and where, specifically it appears.

 

Otherwise all our members who can do is wonder and guess as to what your problem is and where it occurs.