9 replies to this topic

I need help from experts member


Unit consist of two booster comp if one comp under maintenance other one will be online but problem is glycol lost occurred during starting comp .My equation is what could be reason of that?

Best regard,
P/ENG

[Zauberberg]

How can you expect from us to give you any comment, without knowing the basic description of process and flow scheme? To be honest, I don't have any idea what are you speaking about.

How can you expect from us to give you any comment, without knowing the basic description of process and flow scheme? To be honest, I don't have any idea what are you speaking about.

Thanks for you participated,

Typically, glycol dehydration for natural gas are known for most of engineers. I still appreciate your feedback. It might that I have missed to give further explanation regarding subject above. However, when gas compressed @ rate of 49 MMSCF through booster compressor” reciprocating type “ then it flows into glycol contactor where gas get dehydrated by TEG.

It has been noticed when one compressor is under maintenance, due to any reason, the other one is online. During started compressor operation frequently need to add 5 BBLS of glycol. It seem that when gas flows to contactor @ high flow rate carry some of glycol. My equation is there any way to avoid losing of glycol .

Thanks ,
P/ENG

[djack77494]

frequently need to add 5BBLS of glycol

P/ENG,
That's a lot of glycol to lose. It's quite dificult to surmise your situation with the sketchy information you've provided. Why don't you develop a sketch in Excel and present that to the forum members. You're much more likely to get a good response with that added information.

[sri]

I would like to tell my experience in operating the glycol units.

During start up of plant (compressors and glycol units) after shutdown, we used to bypass the glycol unit before starting the compressor.

Glycol pumps were run and circulation established. Reboiler temperature was gradually increased. Gas was then slowly charged into the units. This way glycol losses were less.

I do not know whether this is the problem at ur end.
May try once. Pl also refer your operation manuals for plant start up after shutdown.

[Art Montemayor]

P/ENG:

5 barrels of Triethylene Glycol is a very large quantity of make-up glycol to any unit. That is why Zauberberg and DJack are concerned and trying to help you resolve just exactly what is going on with your dehydration unit. That quantity of glycol is simply not acceptable. It has to go somewhere else if it doesn't appear within your dehydration system. In spite of what Zauberberg and DJack are asking, you still persist in furnishing excuses instead of details and complete descriptions of the unit and the operating procedures. Having designed, started up, and operated various TEG dehydration units, I can safely state that something is wrong in the basic design or you are not operating the unit correctly. There should be NO glycol losses registered during a feed compressor startup.

I am willing to bet the answer is a very simple one; Zauberberg, who happens to be in Muscat, is very capable of finding a logical answer. But you have to furnish us with ALL the details and descriptions of what you have and what is going on. Please follow DJack's request and generate a detailed P&ID sketch with all the basic data:

who designed and fabricated the unit;age of the unit;
the design unit capacity;
the present operating unit capacity;
the pressures, temperatures & flowrates;
the existance of startup and operating manuals;
the detailed compressor startup procedure;
has this glycol loss been occuring in the past? or is it recently?

Any additional operating and startup information would be helpful as well. Contrary to what you assert, we DO NOT KNOW what TEG dehydration process you are using. We don't even know if you are using TEG. You've never even identified it. It could be DEG for all we know. When you say you "might" have missed giving us some information, you are refusing to acknowledge your failure to give us all the basic data required to answer your query. If you are truly a professional engineer, you should recognize that fact and correct it so that we all can get on with our combined efforts to try to help you out.

Await your rapid reply.

Initially, I want to take this opportunity to say that you, Zauberberg and DJack are high effective engineers in this forum not only in engineering side but many things that I have observed in this forum thanks all of you. Honestly I am not professional engineer but I am willing to achieve that by your helps. I am confessed to you that my study in process engineering not complete yet, meanwhile I am working for that. I will gather all data that you have mention but this will take time. Addional on that I would like to ask Zauberberg as you mention, capable of finding a logical answer I would like to ask him.
How can way confirm if column is flooding or not? I want to know that because it seem to me that operation even losing glycol during steady operation.

[Zauberberg]

P/ENG,

Thank you for your compliments and kind words. However, comparing myself with Art Montemayor or Doug is simply not in place - these guys are having the entire-life experience in chemical/process engineering, while I am - in a manner of speaking - still at the beginning, and learning many things as new jobs/projects arrive. Somehow I feel that this kind of comparison is simply not true.

I'm sure we can be of help once when you upload the sketch/P&ID of the system you are speaking about, with a detailed description and process parameters. SRI has also offered his advice; however, there are many differences in design and configuration of TEG units/gas plants, so the procedure he proposed may not be applicable for your particular service. Imagine, for example, there is turboexpander downstream of TEG unit, having gas expanded to subzero temperatures - bypassing dehydration unit, in such case, can be dangerous and could lead to equipment damage due to ice/hydrate formation. The best way is if you can give us more detailed information, and then we can observe the problem from an engineering perspective. And we can discuss about column flooding as well, if there is any indication this phenomenon is occuring in your system.

Best regards,

[Qalander (Chem)]

Dear P/ENG Hello/Good Evening,

May I simply re-phrase in my words what has been said and advised by our honourable Art and Doug & also by friend Zauberberg.

Please Give us(post) a sketch of your under discussion plant showing the process equipment details with key values of control parameters like pressure, temperaure, level and flow rate etc.

this seems to the only possible way to help you.
Kindly cosider/understand.
Best regards
Qalander

[Neelakantan]

hi all,

the p/eng guy never came back with details? i was searching the forum for glycol systems generally and stumbled on this.

however, it is interesting to see a guy asking for help without any details, like a guy waving from across the road. we all see he is shouting and gesticulating but no valid information. We even dont know if he is in troubling or waving his hand to us or somebody behind us!
lols

regards
neelakantan