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How to... Sieve Trays
How to design and optimize Sieve Trays
Sieve trays have been used for about a hundred years and are therefore one of the best studied tray type. They can be easily adapted to different design scenarios (flow rates) using different perforations, they do not require any special tool in production and thus are inexpensive to manufacture.
How to... Bubble Cap Trays
How to design and optimize Bubble Cap Trays
Bubble Cap trays have been used for about 80 years in technical applications and are a very well studied tray type. Nowadays, they are mainly used for handling low liquid loads, as for this field of application there are only few alternatives!
How to... Float Valve Trays
How to design and optimize Float Valve Trays
Float Valve Trays (also called movable valve trays or ballast trays) are the most flexible tray type among the standard trays. They have been used for about 80 years in technical applications, they are well studied and they are still the mainly used tray type in towers.
How to... Fixed Valve Trays
How to design and optimize Fixed Valve Trays
Fixed Valve trays were first published and patented by Nutter in 1967. After some improvements in scale and development of NC-machinery, they gained technical relevance in the 1990s. Therefore they are the most recent, technical relevant development in contact elements of trays.
How to... Downcomers
All about Downcomers and Weirs
To understand all the complexity of trays, it is necessary to get an overview of the various shapes and layouts of downcomers.
How to... Random Packings
How to design and calculate Random Packings
Random Packings (“Rings”) are universal all-rounders: they are not expensive, have good separation
performance, low pressure drop, adapt to the column diameter and are available in many sizes, types
and materials. They have been in technical use for more than 100 years.
How to... Chimney Trays
How to design Chimney Trays
Chimney Trays (also called „Collector Trays“ or „Draw-Offs“) are not used for mass transfer – but they
are important and sometimes also critical components for the operation of columns. This article
describes the functions, designs and leakage classes of these trays.
How to... Tunnel Trays
How to design Tunnel Trays
Tunnel trays are more than only „trays with rectangular bubble caps“. There are two variants of orientation of the tunnels on the active area with specific features. Even though there is only few and rather old public literature of Tunnel trays, this tray type is used in many applications.
How to... Structured Packings
How to design Structured Packings
Due to their construction, structured packings can provide a very large surface area for mass transfer
while maintaining a low pressure drop. After the introduction of sheet metal packings in the 1980s
and the initial euphoria to displace all other column internals, nowadays they have found their firm
place for several applications.