Crude Oil Desalter - Downstream

PROSERNAT Electrostatic Coalescence technology was also designed for refineries, before heating and distillation. Installed in the Preheat train, the Refinery Desalters are used to reduce salt content in oil to limit corrosion in downstream equipment, reduce erosion by solids and increase oil recovery.

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