Devices and processes for deasphalting and/or reducing metals in a crude oil with a desalter unit

A process of desalting and deasphalting crude oil, the process comprising:

• mixing a wash water stream and a crude oil stream to form a water-in-oil emulsion, wherein the crude oil stream comprises water soluble salts and asphaltenes;
• separating the water-in-oil emulsion in a desalter unit to form a first stream comprising water and water soluble salts, a second stream comprising asphaltenes and water in an interface phase, and a third stream comprising desalted and deasphalted crude oil;
• and
• adjusting a location of a nozzle for the separating of the second stream based on changes in a height or a level of the interface phase.

A method of increasing metal-containing crude oil processing capacity in a refinery with a hydroconversion unit having a metal-based operating constraint, the method comprising:

• using a process of desalting and deasphalting crude oil to remove at least a portion of metals from a metal-containing crude oil in a desalter unit, the process comprising:
• mixing a wash water stream and a crude oil stream to form a water-in-oil emulsion, wherein the crude oil stream comprises water soluble salts and asphaltenes;
• adding chemicals to the wash water, crude oil, and/or water-in-oil emulsion to increase a size of an interface phase at an oil-water interface;
• separating the water-in-oil emulsion in a desalter unit to form a first stream comprising water and water soluble salts, a second stream corresponding to the interface phase and comprising asphaltenes and water, and a third stream comprising desalted and deasphalted crude oil;
• and
• withdrawing the second stream from the desalter unit without recycling any portion of the second stream back into the desalter unit;
• the method further comprising increasing a volume of the metal-containing crude oil to the refinery until an amount of metals in a feed to the hydroconversion unit reaches the metal-based operating constraint.