Crude Oil Heater

[Mohamed Miloudi]

Dear Experts/Engineers

In our Oil field facilities we are facing high level of salt (> 60 PTB) in the shipped oil, in particular during cold periods of the year. Here is a summary of the issue:

We have 4 producing stations ( each station has a 3 phase production separator, a wash and surge tank) of crude oil with different WC, Salt Content , but mostly high salt due to high water production due to reservoir pressure depletion as well as reduced equipment performance ( Old). The streams from these station are collected to a central pumping station . There is a plan to install a heater to mitigate the salt issue. My question is , where to install this heater ? at the station with the highest level of salt? is it upstream the production separator? or at CPS?

Any recommendations on the design and installation?

Kind Regards

 

[georgeverghese]

CPS would be a good location for this heater treater.
For safety and operational reasons, suggest setting up a hot oil closed loop heating circuit, and heat the crude in a shell and tube TEMA "U" HX with hot oil on shellside. Tubes should be accessible for mechanical cleaning. Other equipment required will be a preheat HX, 3 phase separator, flash gas recovery or disposal equipment and decant water handling equipment. This arrangement is more expensive, but it has its long term advantages.

 

[Mohamed Miloudi]

CPS would be a good location for this heater treater.
For safety and operational reasons, suggest setting up a hot oil closed loop heating circuit, and heat the crude in a shell and tube TEMA "U" HX with hot oil on shellside. Tubes should be accessible for mechanical cleaning. Other equipment required will be a preheat HX, 3 phase separator, flash gas recovery or disposal equipment and decant water handling equipment. This arrangement is more expensive, but it has its long term advantages.

Thank you very much for your reply. Could you please advise in case I install this heater at the station that produced higher rates of water ( high salt). What are the risks I'll be facing? What are the parameters I need to watch to get a proper design?

For information the suggested heater consists of a fire tube section to preheat the emulsion ( Oil-water), then it flows over to a coalescing section ( electrostatic part) which has a spreader in the lower section to inject water.

Appreciate your prompt reply on this

 

[georgeverghese]

Well, you may be getting higher water rates from one station for now, and maybe from another 5-10years later ?

Electrostatic dehydrators work okay in some plants and dont work at all in many other plants. Emulsions in the feed can mess up electrostatic coalescence. Many different subvariations in this type of dehydrator - am not an expert on this subject.