The MultistockTM is
a single shell compact column containing several integrated trays or
In the upper part of the MultistockTM the
oil is heated to deodorising temperature and then cooled in the lower part of
Thermosyphon heat exchange
This is accomplished with the thermosyphon heat recovery system in which the hot
oil after deodorization is used to generate steam, which is condensed in the top
tray to heat the incoming bleached oil.
In the second tray the oil is heated to deodorization temperature with high
In the deodorizing trays the oil remains as a batch in the tray and movement
must be induced.
This is done by introducing the stripping steam into the tray in a number of
Optimum contact area
The high capacity pumping action produced results in rapid circulation of the
oil in the tray. The oil at the bottom of the tray is moved to the optimum
contact area at the surface many times during the process cycle.
A large surface area between oil and steam is ensured by the initimate contact
within the gas-lift pumps and also by the generation of a thin film at the
discharge of each pump.
With this steam injection system, a deeper oil layer improves the circulation
rate of the pumps.
Therefore, the overall diameter of the MultistockTM may
be kept within reasonable limits.
After initial cooling in the thermosyphon system, the deodorized oil may be
cooled to discharge temperature in a number of ways with the possibility of
obtaining some extra heat recovery:
Generation of a constant supply of hot water,
Generation of low pressure steam
A second thermosyphon to heat incoming oil
Using water from the cooling tower
The MultistockTM is
designed for the factory requiring maximum flexibility in processing different
feedstocks daily. Product change is totally automated with the possibility of no
production loss and minimum interstock contamination. The MultistockTM vessel
mechanical design and process operating data covering normal operation, start-up
and shut-down conditions have been submitted to rigorous finite element analysis
for possible metal fatigue problems due to the thermal cycles (400.000 cycles
over 20 years operation). ??The highest stressed areas are strengthened and
welding specifications guarantee a long working life.
Frequent stock changes : up
to 40/ day
Adaptable batch size : flexibility
Proven and calculated reliability
Low contamination : product
Ideal coil design
Excellent vapour scrubbing