A number of processes in industrial settings — including stripping, distillation and absorption — rely on packed columns or packed towers to operate efficiently. In situations where more than one packed bed is employed within a tower, there are often both liquid distributors and liquid redistributors at work.
Along with liquid distributors that operate to evenly distribute liquid across a tower’s sections of packing, liquid redistributors — also known as liquid collectors — are tasked with first collecting and then redistributing liquids from an upper part of the tower to a lower section. In combination, the use of distributors and redistributors helps ensure an effective transfer of liquids and substances between phases. It also helps prevent uneven distribution.
Benefits of a Liquid Redistributor
Liquid redistributors are not always necessary. However, when they’re employed correctly, they offer several advantages. Well-designed liquid redistributors:
- Allow the introduction of multiple feeds.
- Permit the side draw of different products.
- Help the cross-mixing of dissimilar liquids.
- Facilitate stage counts of a high theoretical nature.
- Prevent the maldistribution of liquids.
The Different Types of Liquid Redistributors
Our design team at MACH Engineering offers a wide range of both semi-custom and custom products — including liquid redistributors — for your specific business applications. Of all the types of liquid redistributors available, the most common kind in use today is the orifice type liquid redistributor, also known as a plate or pan-type liquid redistributor.
Orifice Liquid Redistributor
This type of tower internal collects and redistributes liquids by being installed under a section of the packed bed. Much like the Orifice Liquid Distributor, it will contain a deck and chimneys. These redistributors are designed with a series of hats or caps that prevent water and/or liquids from bypassing the section of the equipment used for collecting.
Liquid Collector Draw Off
This type of liquid collector is versatile in design and construction depending on the application requirements. The design features tall vapor risers, allowing it to retain large holdup volumes on the deck.
Liquid Redistributor Considerations
It’s important to remember that the introduction of a new vapor feed or liquid to a packed tower typically requires sufficient space and equipment within the packing for the proper redistribution of the liquid phase.
Factors such as the composition and temperature of the new feed in comparison with the internal liquid must be considered. But in many cases — except when feed rates are relatively small — the use of liquid redistributors is advisable to provide uniformity of the liquid before it passes down to the next level of the packed bed.
Note that when liquid cross-mixing occurs without the use of liquid redistributors, the risk of maldistribution can rise dramatically.
Benefits of Working With MACH Engineering for Your Liquid Redistributor Needs
With over 25 years of specialized service meeting our customers’ needs, MACH Engineering specializes in process tower engineering. We can also supervise the installation of tower internals. Whatever your needs are — from process optimization to debottlenecking — we’re here to help you and provide you with the best possible products, advice, and outcome.
To learn more about our outstanding products and services — including our quick turnaround times and innovative designs — contact us at your earliest convenience.