2 replies to this topic

[CHEMSTRONG]

Dear Sir,

 

I have got light crude oil two stage desalting system with wash water addition in desalter.

 

I want to know about crude oil desalting system modelling in hysys. I have used carry over tab in separator option for separation of crude oil and water also. I have configured interface level controller also for water

 

But I could not show separation of salts. I have shown mixing valve delta P with dummy valve with pressure drop , larger delta p for second stage desalter and less pressure drop for first stage desalter .

 

Best Regards,

Chetan Chavan

[Technical Bard]

I wouldn't waste my time doing this in HYSYS. Just use a spreadsheet.  HYSYS will also assume 100% contact efficiency between the wash water and the connate water (salty brine) droplets in the oil, which won't be true.  The reality will be that your contact efficiency will be between 70 and 85%, depending on your oil properties, chemical blend and mixing valve.  

[gegio1960]

i don't know the scope of your simulation, but i can comment as follows:

- ok for quantity of wash water and pressure drop thru the mixing valve. you can follow the real (realistic) heat, material and pressure balances

- just add a control to leave in the outlet crude the concentration of water guaranteed by the desalter vendor

- the salts doesn't enter in this kind of simulation. for instance, you can't simulate their thermal decomposition with consequent generation of HCl and the relevant corrosion effects on the top of the topping tower

good luck!