Advantages of Sieve Trays :

• Good operating effectiveness,
  

• Simple design

• Low cost and easy maintenance .

• Be resistant to heavy fouling services and offering high capacities.

Disadvantages of Sieve Trays :

• Low flexibility

• Low to moderate performances.

Advantages of Dual flow trays:

• Vapor rate maintains the plate liquid level and the hole size will be defined for optimizing the performance.

• When dual flow trays have high open area,capacity tend to be higher and pressure drop tend to be lower, being particularly suitable for containing a moderate to high solids content

Distillation column

The column internals provide a contact place for mass transfer and heat transfer for the gas-liquid phase and liquid-liquid phase; There are two main types of column internals: packed column and trayed column. The packing column internals mainly include packing, liquid distributor, liquid collector, redistributor, gas distributor, packing fastening device, packing support device; trayed column internals mainly include: tray, liquid collection tank (trayed column), tray support device (trayed column), feed distributor, gas feed and distribution device and mist eliminator.

Distillation trays

To ensure vapor and liquid phases contact intimately with distillation trays,a distillation process is defined as below:
First ,mixture of vapor and liquid will form froth，within which mass transfer will occur then the froth will overflow across a weir .Next, the vapor will be released upwards to the upper tray ,and the bulk liquid will flow downwards to the next tray.