Crude Oil Desalter

PROSERNAT Electrostatic Dehydrator / Desalter is a crude oils separation technology developed for several applications in onshore, offshore or floating environments: new crude units, revamp of existing units for increased capacity and/or treating more viscous crudes, addition of a second stage of treatment for higher efficiency, improvement of the desalting efficiency and water quality and reduction of demulsifier consumption.

Process Principle

The Desalting process comprises two fundamental sections : water dilution & emulsification and electrostatic coalescence & separation which is performed thanks to an optimized internal arrangement for a better electrostatic coalescence, a special designed power unit and an entrance bushing arrangement.

Crude Oil Electrostatic Desalting Principle :

  • Salt contents in crudes depend on residual water droplets after primary separation
  • Injection and emulsification of dilution water
  • Electrostatic coalescence of the emulsified droplets
  • Settling of larger drops

Process Scheme



  • Over 150 industrial references
  • Certified power units
  • Controlled emulsification
  • Optimized emulsion distribution in the electric field
  • Reduced use of dilution water and demulsifier
  • High efficiency single or multi-stage applications:
    • Production applications: 20 PTB of salts / 0.5% BSW or less
    • Refinery applications: down to 0.5 PTB of salts / 0.1% BSW
  • LPG treatment: down to 10 ppm insoluble aqueous phase
  • Single train capacity up to 300,000 BPD

Key Benefits

  • Refinery and production fields application
  • Reliable and flexible electrostatic coalescers
  • Static technology for minimal supervision and low maintenance
  • Handling of high water cut and high sediment content
  • Special design for FPSO and topside to deal with roll and pitch issues
  • Extensive experience both in grassroot and revamping of existing units with minimum modifications at site