6 replies to this topic

[mayuresh]

this is my first of its kind experience.

Hoping that everyone would connect to my query at hand.

 

i just need to know how a particular equipment (in my case a stabilizer column) could work under two different pressure.

 

or to be more clear, how does a column working in say, (x1 bar/top) and (x2 bar/bottom) benifit the sabilizing process??

 

if anyone out there would spare a moment.

 

hoping i was precise in presenting my doubt.

 

 

 

 

[colt16]

The purpose of stabilization is to remove the residual gases from the feed liquid.  If done properly, the liquid that comes out of the bottom of the column will not release gases as it is transported or stored in storage tanks. 

 

Typically you want to remove all those items are in a vapour phase at say storage temperature and storage pressure.  Your column conditions should be set such that these items come out at the top of the column.

[mayuresh]

so due to a phase difference existing in the column, say vapour phase towards the top side and the opposite towards down side.

a pressure difference is required for proper sequencing of the stabilizing of feed ??

 

thanks tanykiat for your time.

[ColinR33]

The pressure differential over the tower is due to tray/packing hydraulics (ie. pressure drop through the internals) and is typically fairly low, ie less than 2-4 psi. The pressure difference you describe is highly unusual. How would you propose to control this pressure differential through the tower? Trays/packing are designed to operate as a specific pressure drop under normal operating conditions with a bit of operational variation thrown in, and of course it will vary based on throughput and the composition of your feed and operating temperatures/pressures. Typically differential pressures are monitored as an indication of tower operating condition/stability. An increasing or high differential pressure is an indication of operating problems such as flooding or foaming for example.

[mayuresh]

thanks CloinR33, yes some more study on this topic, i hope to clear all my doubts,

 

so acc to you, "Typically differential pressures are monitored as an indication of tower operating condition/stability. An increasing or high differential pressure is an indication of operating problems such as flooding or foaming for example."

 

if the pressure differential is stable and unless no sharp variations seems to occur then it is a no issue for the Stabilization Pocess. the process continues with the release of some residual gases ?? Correct??

and the cause of this pressure differential is the Internals namely, TSR, packing,etc.

 

Thanks Again,CloinR33.

[ColinR33]

Mayuresh,

Yes, if operating dP is stable that is typically a sign of a stable process, and if it is not appreciably higher than what was calculated at design stage (assuming you are running at the design conditions) then that is a sign it is operating correctly and there are no issues with the internals. As a stabilization tower is typically used to remove light ends and other contaminants such as H2S from a liquid feed, yes, there will be a constant stream of vapour leaving the top of the tower. How much depends on the degree of stabilization required, feed composition, tower operating conditions and other factor.

By the way, it is ColinR33, not CloinR33 ;-).

[mayuresh]

thanks ColinR33.