First let’s
start with structural packing which is commonly in demand across
different industrial sectors. Structured packing is highly popular
because of its versatile range of applications. They are considerably
more expensive than random packings. The range of materials used for
structured packing is specially designed for use in distillation and
absorption columns.
Structured
packings come in a variety of materials, which includes metal,
plastic, or wire gauze. The thin corrugated metal plates result in
inclined flow channels with a high surface area.
Some of its
essential features include high separation efficiency, low-pressure
drop, good wettability, boosts useful capacity, etc. You can find
many structured packing suppliers
who deal with many other types of structured packing.
Random
Packing
Random
packing is mainly used for absorption, stripping, fractionation
operation in gas and chemical plants. They provide an increased
surface area, which results in a more efficient process. Unlike the
structured packings, their arrangement is not in columns with any
specific method or orientation. Some of its important features
include cost-effective, high mechanical strength, and they are
available in different sizes, which gives a different combination of
efficiency and pressure drop.
Mass
Transfer Trays
They play an
essential role in thermal fractionation. Mass transfer trays are used
for distillation processes in chemical plants. Following are some of
the trays available for mass transfer.
1. Sieve
trays- Sieve trays are punched holes for passage of the gas. With
limited load range, sieve trays are the simplest and hence the
cheapest types of mass transfer trays available.
2. Valve
trays- In the valve trays, liftable caps are used to cover the
perforations. They use a dynamically variable valve opening, which
eases the gas flow rate.
3. Bubble
cap trays- These are another variety of trays that are made with
inverted bubble caps having vertical slots fixed over cylindrical
risers. They are also suitable for low liquid loads.
4. Dual Flow
Trays- This tray operates with liquid continuously seeping through
the holes. It's like a sieve tray with no down corners, which give
more tray area and higher capacity than any other type.
Packing
vs. Trays
Trays are
suitable in application with liquid rates of 30 m3/m2 and above.
Structured packings are typically used in lower liquid rate
applications. Trays and packed columns both have several advantages
and disadvantages according to its area of operation. One of the
benefits of packed towers is that it provides continuous contact
without full disengagement of the vapor and liquid.
With this,
ease of installation, mechanical simplicity is its other significant
advantages that you can take into account while making a purchase.
When it comes to trays, with its benefits, they do have some
operating limits which depend upon the area of its uses.
Last but not
the least, before choosing the right product, it is essential to
consider a variety of issues to make the best choice regarding the
type and design you want for your own requirement. The
above-mentioned information would help you to make more informed
decisions.
