Best Type of Reboiler for 250kW Duty in Light Hydrocarbon Service 1

[EmmanuelTop]

Good day,

I hope to get some insight in selection of type and heating medium for rather small reboiler, serving the stabilization column for light Hydrocarbons (range from C1-C12). The liquid feed of the column flows from the low-temperature separator (as a product of hydrocarbon dew-pointing of the gas) and is free of solids and any other contaminants.

I believe that employing kettle or horizontal reboiler would be a waste of money, for such small heat duty. Employing hot oil package to supply the heat would be another money waste, I guess.

I went through a lot of literature and online discussions, seeking for optimum solution. The questions however remained without answer. What is your experience in these systems? Should I consider e.g. electrically heated stab-in reboiler, or a small vertical thermosyphon heated by hot oil? I am really without a clue. Something is telling me that employing hot oil or other heat transfer fluid package is simply not the right way forward, but there is no other fluid on the site that we could use as the source of heat.

Thank you in advance,
Best regards

Dejan IVANOVIC
Senior Process Engineer

 

[gr2vessels]

Dejan,
You have eliminated the obvious heating sources which require additional heater. However, you need heat source, other than strong faith.
Do you have any fuel gas system on your plant? Do you need (or have) on your plant a heat recovery system where you could tap in for some heat? I guess you don't have steam on your plant, do you?
I'm sure you have exhausted all these 'ideas', but simply you need a source of heat. In absence of anything else, the stab-in electric heater bundle is your best option, clean and easy to control.
Give us a clue on your lateral ideas.
Cheers,
gr2vessels

 

[EmmanuelTop]

Thank you for your reply.

Yes, there is a source of clean Fuel gas in the plant. No steam, no heat recovery systems available.
Is fired reboiler an option?


Dejan IVANOVIC
Senior Process Engineer

 

[gr2vessels]

I suggest use a small standard oil heater with your fuel gas, there are standard packages you buy, bolt down, pipe and use. That is, you'll need an oil heated stab-in exchanger with some basic temperature controls. The oil heater comes with its own controls, you might install the heater on the platform next to the stab-in exchanger, provided you get your gas pipe around.
Cheers,
gr2vessels

 

[EmmanuelTop]

I completely agree with you. Are there any alternatives?


Dejan IVANOVIC
Senior Process Engineer

 

[gr2vessels]

Use water instead of oil? Use the actual process hydrocarbon as heating fluid in a closed or open circuit from your gas heater. You may return the hot hydrocarbon in the upstream process for pre-heating the flow or use it in a close circuit and replace it when required, periodically. Many solutions available and not very expensive (provided you have the available nozzle for the stab-in solution, spare nozzle for the return of hot hydrocarbon, etc depending on the selected heating process.
Cheers,
gr2vessels