Alternative Sequences of the Separation (Plate Column and Packet Column)

Here the definition of Plate Column and Packet Column

Plate Column


The tray column (1) has downcomers (3) for transporting a liquid between adjacent trays (2). The liquid transport takes place in each downcomer through a plurality of discharge apertures (32) onto a loaded tray. Liquid flows out of the discharge apertures in the form of jets (60) that blend into a regionally divergent flow field (6) on striking the loaded tray. The flow field has transverse components of the flow speed with respect to a longitudinal main flow direction (61). Guide elements (4) are arranged beneath the discharge apertures and at a spacing from the loaded tray which each guide the impulse of liquid corresponding to the divergent flow field. The guide elements contribute to forming the transverse speed components such that the longitudinal component of the flow speed has a largely constant profile in each plane perpendicular to the main flow direction. The discharge apertures are preferably made in different sizes in a graduated fashion to be smaller in a central region than in adjacent flank regions.

Packet Column

In chemical processing, a packed bed is a hollow tube, pipe, or other vessel that is filled with a packing material. The packing can be randomly filled with small objects like Raschig rings or else it can be a specifically designed structured packing.

The purpose of a packed bed is typically to improve contact between two phases in a chemical or similar process. Packed beds can be used in a chemical reactor, a distillation process, or a scrubber, but packed beds have also been used to store heat in chemical plants. In this case, hot gases are allowed to escape through a vessel that is packed with a refractory material until the packing is hot. Air or other cool gas is then fed back to the plant through the hot bed, thereby pre-heating the air or gas feed.

 

 Here the differences of Plate Column and Packet Column

Plate or Tray Column	Packed Column
Vapor contacting is better	--
Liquid hold-up is better	--
Easy to cleaning	--
--	Less pressure drop, so its suitable to vacuum operation
--	Cheaper for corosive fluid
--	Suitable for little diameter
Can be used for liquid which contain solid particle	Solid particle can suspending the flow
--	Suitable for foaming liquid
--	Less heavy (light)
Side stream avaiable	--

source :
Packed Column Wikipedia
Tray Column Freepatents Online