Organic vapours such as e.g. ethylene-glycol, butandiol, butanol,
mono-chloride benzol, trichloroethylene, may all be used as a motive
medium for ejectors operating with vapour from the process.
The suitability of a substance as a motive medium is determined by its
vapour pressure curve. The decisive factor is that the evaporation temperature
should be less than the decomposition temperature. The temperature of the
available cooling agent determines the necessary condensation pressure and
can absolutely exclude the use of certain motive flows. Vapour pressure alterations
caused by low-boiling components must be taken into consideration.
Typical applications
- Vacuum generation for polyconden-
sation
processes e.g. PET, PBT
- Vacuum generation for special products
|
|
Advantages of this type of system are:
- Suction- and operating flows are identical
- Pollution-resistant
- Trouble-free operation for years
- No need for a stand-by system
- Economical operation
- No waste water
Flow sheet
|