5 replies to this topic

[fuzzhezy]

For some reason I can not figure out this issue. The issue is that the Rich Glycol in the Low Temp. Separator level builds and can not escape through the Level Control Valve or the Bypass line around this valve. 

The LCV is not plugged, is sized correctly, and is totally functional.

The Bypass line around the LCV i mentioned above is not plugged neither.

The piping that goes from the Low Temp. Sep. to the still stack on the Reconcentratoris not plugged neither.

The glycol filters are not plugged.

There is no plugging issues anywhere. (Trust me, I took apart everything including valves, piping and still stack)

The flash separator pressure is around 60 psi.

We are injecting 80% Glycol at .6 gpm to 3 injection points at 500 lbs. each

The incoming gas to the G/G exchanger is around 85 degrees Fahrenheit and 400 psi

The LTS is -35 with usually 360 psi on it

 

I will explain the flow

 

Rich Glycol leaves the Low Temp. Separator at -35 degrees Fahrenheit and at 380 psi through a Level Control Valve.

Rich Glycol is directed to the Reconcentrator Still stack to get warmed up

From the still stack it is directed to the Reconcentrator Surge tank to be warmed up again. 

From the surge tank it is directed to the Flash Separator

From the Flash Separator it is directed through a Particulate Filter then through a Coal Filter

From the Coal filters it is directed to the Still Stack, where it finally comes into contact with the vapor from the reconcentrator and goes through pall rings and rains down into the reconcentrator 

From the reconcentrator it is now Lean Glycol and Flows into the surge tank where, our Glycol Injection pumps it back to a Gas to Gas exchanger, Gas to Cond. exchanger, and to our Gas Chiller.

 

For some reason could there be issues in the still stack when the still stacks temperature fluctuates from 200 degrees to 60 degrees? Meaning the glycol hydrocarbon carryover from the LTS is dropping out more when temperatures are too hot and the hydrocarbon starts to freeze up when the temperatures in the still stack start to decrease causing pluggage? 

 

Are we running too cold or too hot in certain areas?

 

Is my Glycol concentration too high at 80% glycol?

 

 

 

I have no clue whats going on and if you need more information on anything let me know!!!!

Edited by fuzzhezy, 18 June 2015 - 12:11 AM.

[Bobby Strain]

You won't get much help without a sketch.

Bobby

[Art Montemayor]

Fuzz:

 

As Bobby has explained, you can't expect people to understand what you are stating if you don't provide a detailed engineering sketch in the form of a P&ID with temperatures, pressures, and flows indicated.  I presume this is a low temp field glycol dehydration injection system somewhere out in Colorado and it is freezing up on you.  You don't identify WHAT glycol you are using and what you call "rich" glycol.  Depending on the glycol, it isn't "rich" at 80% (wt); it could be super-saturated with liquid water.  We just don't know.  Give as much back ground and history as you can.

 

This is not a packed tower problem that you are describing.  I will move this thread where it best belongs in the Forums.

[fuzzhezy]

I will draw something out when I get to work tomorrow. What do you all want on this drawing besides the Low Temperature Separator Glycol and Glycol flow to the Re-Concentrator? I will add all pressures, temperatures, valves, and flows to everything on the drawing.

[Napo]

Fuzzhezy,

 

Maybe the problem is in coil for condensation (tower) it can be broken (perforated), so you have the variation of temperature, you has verified this?.

 

What is the pH, and iron and chloride content of the system?, the cause of the problem may be due to corrosion.

 

Napo.

[Karyuu]

Is it possible that the rich glycol has significant amount of water, and is freezing up and causing a clog at -35 F? Then by the time you break the connections, the build up changed to liquid and you never notice anything being clogged?