Tethraetylene glycol gas dehydration units 1

[atayto]

Gents
Can any body help me to find vendor/manufacturer of gas dehydration unit which uses tethra ethilene glycol or dipropelene glycol as liquid absorbent.

 

[Funred64]

There are several. The first that comes to mind is QB Johnson.

Q.B. Johnson Manufacturing Inc.,
Office & Manufacturing Facility
9000 S. Sunnylane Road
Oklahoma City, OK 73165.

Phone: (405) 677-6676
Fax : (405) 670-3270
WATTS: 1-888-834-3349
Email: ljohnson@qbjohnson.com


Address for correspondence:

Q.B. Johnson Manufacturing Inc.,
P.O. Box 890120
Oklahoma City, OK 73189

 

[atayto]

I have already contacted this company. They dont have expeience in designing of tetraetylene glycol gas dehydration unit. Any other ideas. I am currently working on optimization of one TEG gas dehydration units but it is looks like its performance cant be improved without any modification. Existing unit was designed for higher pressure , but later on in order to increase oil production pressure was reduced significantly.Main problem of existing unit is oil carry over from upstream equipment and increased water content in dry gas. glycol regeneration package still can maintain good quality of lean glycol, but packing effisiency doesnt let us to remove required amount of water. The easiest way to improve performance of existing unitis to replace TEG with TrEG. TrEG is much more tolerant to the hydrocarbon contamination and also more dew point depression can be achieved Water content in dry gas can be reduced twice. I need engineering help from manufacturer of TrEG gas dehydration unit in means of new operating conditions of existing package and also as long term solution some possibly modication for further improvement.

In all case thanks for reply

 

[MortenA]

However, TrEG is more expensive and more viscous.

Best regards

Morten

 

[dcasto]

If you want greater depression, then add a stahl coulmn or a cold finger.

Put a coalescing filter upstream of the contactor to keep the oil out. Make sure your glycol is a few degrees warmer than the gas. This should stop the oil in the TEG.

The issue is most likely that you have more pounds of water to remove at the lower pressure. This means you need more circulation rate and more reboiler.

I'm not so sure about TrEG having a greater dew point depression unless you can get it's purity a lot higher. Dew point depression is a function of the glycols purity at the top stage more than anything else.

 

[atayto]

Package was designed for 37barg and 45 deg C with capacity of 170MMscfd. Currently package operates at 26 barg and 45 deg C with throughput ot 160MMscfd. according to calculation we operate very close to flooding point. Velocityes are increased as in contactor as in upstream separators at lower pressure. So there is big carry over from separators, foaming in separators and high water content in dry gas.Lean glycol quolity is good and water content of glycol is only 0.228% when it was specified in design calculation it should be around 0.6%. Circulation rates are increased, I beleive because lower pressure in contactor(dont understand why, it is reciprocating pump). Now we are looking through two options. Option one is to install coalescer filter(PALL company made) upstream of contact and inline static mixer(Sulzer). This will be something as additional theoretical stage. Another option (I beleive cheap option) is this focus pocus with TrEG. Currently we cant improve glycol purity. Amount os stripping ga sis maximum possible. There is constant sign of foaming in reboiler. It disappears when stripping gas is reduced. As I know TrEG doesnt require strippng gas for purity up to 99.9% at regeneration temperature of 204 deg C. So it will give us another dew point reduction.

Thaks for rplay , all answers make me think again and i really appreciate your help.

 

[dcasto]

the water content went from 130 lb/MMSCF (22,100 gpd)to 190 lb/mmscf (30,400 gpd). TEG requirements go from 2900 GPH at 99.2 wt% to 3800 GPD at 99.4 wt%. The tower diameter is at least 10% to small depending on tray design, this would be a bigger issue with TrEG because the volumetric circulation rate will increase even more.

The rebolier duty goes from 5.5 MMBTU/hr to 7.2 MMBTU/hr. This will be true for TEG or TrEG. Are you sure your reboiler is big enough too?

 

[atayto]

Contactor diameter 2 meter and it is equiped with structured packing.It has relative area of 225m2/m3. I calculated circulation rate using GCAP software and it is the same as you mentioned. but problem is packing if we are going to change circulation rate then we have to change packing. Circulation rate is 8.7m3/h(2300GPH). Dont remember from top of my head but difference between TrEG dencity and TEG dencity is very little.

About reboiler. Heater never was loaded even up to 75% of load. And glycol purity is higher than 99.7%.

Thanks Dcasto you helped me so many times that I need to give you a star for this. Thanks to everybody in this thread.

 

[cckanand]

Mr.Atayto
You mentioned in order to increase oil production you reduced the pressure. Can you please explain me how an increase oil production happens when we reduce the pressure

 

[atayto]

Oil producing wells lined up through manifold to HP separators. Oil flow from a well is controlled by choke valve. Most well choke vales are fully open and oil production is mainly controlled by pressure in HP separtors.The less pressure in HP separators the more differential pressure between reserviour and separators and more oil produced. If you are asking how gas dehydration is affected then gas flows further to gas dehydration without any compressors.

 

[cckanand]

Thanks Mr. Atayto for replying me. So you are saying that this dp will yield to high flow rate right

 

[atayto]

Yes exactly

 

[hianbotech]

Suppliers for dehydration systme with TEG

NATCO
PROSERNAT
FRAMES