High performance liquid distributors aim towards ideal liquid distribution, i.e. equal liquid rate per unit area of the packed bed surface. These distributors are available in a complete range to suit various column diameters, liquid rates and service conditions. Models, which can give turndown ratio upto 10:1, are available. Our design team selects the most suitable model for a given application.
The table below listes some conventional distributors.
Orifice ladder
liquid distributor
Spray nozzle
liquid distributor
Orifice pan
liquid distributor
Weir orifice
liquid distributor
Orifice trough
liquid distributor
Weir trough
liquid distributor
Drive force
pressure
pressure
gravity
gravity
gravity
gravity
Distribute capacity
middle
Low to middle
high
high
middle
middle
Load range
low
low
middle
middle
middle
high
Liquid load (m3/m2.h)
0.25~1.5
Wide range
Wide range
Wide range
Wide range
Wide range
Diameter (m)
> 0.45
random
random
normal < 1.2
random
normal > 1.2
random
random
Resistant of fouling
high
Low to middle
high
middle
low
low
Gas resistance
low
low
high
Low to middle
high
high
Levelness requirement
no
no
yes
yes
yes
yes
Effect on corrosion
high
low
high
high
low
low
Effect on thickness of liquid
no
no
yes
yes
yes
yes
Liquid entrainment
yes
yes
no
no
no
no
Weight
low
low
high
middle
middle
middle
Orifice ladder liquid distributor
Φ3800 Orifice pan liquid collect and redistributor
Orifice pan liquid distributor
Orifice pan liquid distributor
Orifice trough liquid distributor
Bed Limiter
Bed limiters are safety devices that are available for both random as well structured packing to avoid the expansion of the packed bed, as well as to maintain the bed top surface level.
Support Plate
Support plates in addition to providing physical support to the packings, must also allow unrestricted flow of gas and liquid. Gas injection support plates provide separate passageways for liquid and gas, which minimizes the pressure drop across the plate. Support plate model is selected depending upon the packing type and size and the maximum design load to be supported.
Collector/Chimney Tray
Collector trays are used to collect liquid from between packed beds. Liquid interception is required in various situations such as total or partial draw-off of liquid, change in the column diameter, which sometimes necessitates the redistribution of the liquid; to cool the liquid in absorbers before passing to the next packed bed etc. Different types of collector trays are available to suit the column diameter and the vapour and liquid rates.
Feed Device
Different feed devices are available for various feed conditions of the fluid entering the column such as only liquid feed, mixed feed or gaseous feed. Feed devices are selected to complement with the type of distributor used to give the optimum performance of each.