EDC/VCM-Process

In the DIRECT CHLORINATION as well as in the OXYCHLORINATION process, ethylene-dichloride (EDC) is produced. Both reactions proceed exothermally.

EDC produced by direct chlorination can be sent directly to cracking unit whereas the EDC from the oxychlorination process has to pass a purification stage (EDC DISTILLATION) before cracking.

In the EDC CRACKING unit, EDC is cracked to VCM and hydrogen chloride. These, together with any unconverted EDC, are separated in a VCM DISTILLATION unit. The VCM, as final product, is sent to the next production stage or for dispatch. The HCl is returned to the OXYCHLORINATION unit and the unconverted EDC via EDC DISTILLATION unit to the CRACKING section.

DIRECT CHLORINATION:	C2H4 + Cl2	C2H4Cl2 + 218 kJ/mole
OXYCHLORINATION:	C2H4 + 2 HCl + ½ O2	C2H4Cl2 + H2O + 238kJ/mole
EDC CRACKING:	C2H4Cl2	C2H3Cl + HCl - 71 kJ/mole

Water obtained from this process is treated in appropriate water purification plants. Waste gases as well as liquid by-products are fed to the HCl RECOVERY unit and converted to HCl.

The recovered HCl is re-used either for the production of hydrochloric acid or in the OXYCHLORINATION process. This leads to a complete usage of the chlorine input.

The modern Vinnolit processes for the production of VCM have the following distinctive features:

High operational reliability:
· reliable reaction control
· proven materials
· state-of-the-art process control and safety system

High economic efficiency:

· high yields

· optimized reaction conditions and reaction control

· low energy consumption

· utilization of chlorine containing by-products

· high on stream time

· low personnel requirements

· low maintenance costs

· high flexibility, wide range of load

Low consumption figures:
Expected consumption figures per 1,000 kg VCM produced:

Ethylene (100 %)	459 kg	Electricity	90 kWh
Chlorine (100 %)	585 kg	Cooling water	130 m3
Oxygen (100%)	138 kg	Fuel gas	2,790,000 kJ
Steam	0 kg