Metal wire mesh packing used in packed tower ready for shipment
Metal Wire Mesh Packing Fixing and Installation
It is a very basic and simple procedure. Once we have optimized the
dimensions of the packing we must ensure that the inside of the
column is clean and has no weld joints or bulges to obstruct the
installation. The supporting structure can be made of two cross
bars at 90 degrees to each other and in larger columns the same
construction must be repeated at a pitch of 150mm.
Once the support is in place, successive modules of structured
packing must be inserted from the top – down. Normally a wooden
disc (having a slightly small diameter than the packing) is mounted
on a pole and used to push each segment down to their position due
to the very narrow diameter of the column.
Characteristics of packed tower
Compared with plate column, packed column has certain advantages,
especially in recent years, a variety of new and efficient packing
has been developed, which has more prominent advantages and wider
application range. Its specific characteristics are as follows:
1. The pressure drop is very low, which can be used in vacuum
distillation and other operating systems with limited pressure
drop.
2. With the development of new high efficiency packing, the
production capacity (allowable gas velocity) and efficiency of
packed tower are equal to or exceed those of plate column. Many
units at home and abroad use new packing to transform plate column,
which greatly improves production capacity and efficiency.
3. Flexible operation.
4. It can deal with foaming system.
5. General fillers are easy to be blocked by suspended solids in
the liquid, while some grid fillers with large void fraction have
self-cleaning effect under high gas velocity scouring, and are not
easy to be blocked, and their heat transfer performance is better
than that of baffles.
6. The material selection of fillers is wide, such as metal,
plastic, ceramic, graphite, etc., which is suitable for wider
chemical system and operating system.
7. Small liquid holding capacity, suitable for the treatment of
heat sensitive materials.
8. The total investment cost of small tower (diameter ≤ 0.6m) is
lower than that of plate tower, but the investment cost of large
tower is higher.
9. The heat exchange in the middle of the tower is inconvenient.
10. It is difficult to draw out the side line and the structure is
complex.
11. High requirements for initial gas-liquid distribution.
The process control is difficult because of its small liquid
holding capacity and sensitivity.
Compare: Packed columns offer multiple benefits
| Packed columns | Trayed columns |
| Lower pressure drop leads to significant power savings. (Greater
than 5% reduction in power is possible.) | Higher pressure drop, but shorter columns. |
| High turndown capability. (Down to 40% of design capacity is
possible.) | Limited turndown for efficient operation. (60-70% of design
capacity is typical.) |
| Enables pure argon production by distillation, therefore
eliminating need for a pure hydrogen source. | Can be used for high-pressure distillation.
|
metal wire mesh structured packing ready for shipping
