intimate contact between the vapour and liquid phases is necessary. Pakcol made from crimped mesh of woven wire
filaments provides a large surface to realize the desired inter-phase mixing.
Mechanism
Capillary action of the strands of Pakcol Columns helps in spreading the liquid uniformly over the wire mesh. As a
result, there is no build-up of the liquid anywhere in the voids of the packing. Vapour, therefore, has a free access to
every surface inside the packing. The high separation efficiency is thus obtained as the available surface of the packing
is most effectively utilized.
Salient Features
• Low value of HETP (Height Equivalent of Theoretical Plate):
Typical values range from 100 to 150 mm. Low values of PDTS (Pressure Drop per Theoretical Stage). Typical values
range from 0.04 to 0.05 mm of Hg, depending on the vapour load.
• High vapour handling capacity:
Vapour handling capacity of Pakcol is comparable to 25 mm metal pall rings
• No reduction in efficiency even at low liquid irrigation rates:
Capillary action of Pakcol Columns helps it to achieve uniform wetting of the entire package even at low liquid
loadings. Packing can work without the loss of efficiency at a liquid irrigation rate as low as 0.3 mh (0.5 GPM/FT).
• Performance is independent of Packing Size:
Unlike random packings, the properties of Pakcol Columns are independent of packing size. Hence, its performance
characteristics, such as HETP and PDTS, are practically independent of packing diameter.
• No wall effect:
Pakcol draws liquid from the wall of the column into its interior by capillary action. No liquid redistributors are
therefore necessary for a column packed with Pakcol.
Advantages
Although Pakcol Column Packing appears to be expensive, it will prove to be the most economical solution to your
problem if you weigh each of its following advantages.
• Reduction in packed volume:
This is achieved due to low HETP of the packing
• Reduction in the cost of the column shell and supporting structure:
This follows as a consequence of the lower packed volume.
• Saving in energy cost:
This is possible through a reduction in the reflux ratio.
• Reduction in product loss through product degradation:
The use of Pakcol allows you to achieve reboiler temperatures for a specified column top pressure. A lower reboiler
temperature reduces the rate of degradation of heat-sensitive materials present in the reboiler, resulting in high
product yield.
• High flexibility:
Since Pakcol shows high performance over a wide range of liquid loadings, it is most suitable for the situations which
demand flexibility, such as batch operations, unsteady state operations and multipurpose distillation jobs.
• Increased in throughput capacity:
The wide range of operating velocities allows an increase in column capacity that is 2 to 2.5 higher than conventional packing.
