VCM Distillation

The cracking product consisting of EDC, VCM and HCl is separated in the VCM distillation unit.

Hydrogen chloride is recovered in the HCl column and fed to the oxychlorination unit.
Vinyl chloride is obtained at the top of the VCM column and traces of HCl are removed in the HCl stripper.

The bottom product of the VCM column, mainly unconverted EDC, is returned to the EDC distillation process after the low-boiling components have been converted to high-boiling components by chlorination.

Advantages of VCM distillation
  • HCl content in VCM < 1 ppm without using caustic
  • Long on-stream time of VCM distillation unit, because of no coke carry-over from hot quench system
  • Vapor feed of HCl stripper overhead product to the HCl column, no condensation system necessary
  • Lower power consumption for HCl condensation compared to low pressure HCl column
Advantages of recycled EDC chlorination:
  • No separation of low-boiling compounds necessary
  • Low investment cost in comparison to a low-boil column
  • Easy operation
  • No steam consumption
  • Low maintenance cost
Back