Why are gas absorption towers mostly float valve towers, bubble cap towers, and tray towers, while packed towers are rarely used?
Thread Content
Why are floating valve towers, bubble cap towers, and tray towers commonly used in gas absorption and desorption equipment, while packed towers are rarely used? However, packed towers are widely used in fine chemical industry.
The main function of a packed tower is to increase the contact surface area between two fluids through the packing. For example, when used in gas absorption, the liquid enters from the upper part of the tower through a distributor and flows down along the surface of the packing. The gas flows upward from the lower part of the tower through the pores in the packing, where it comes into close contact with the liquid and interacts with it. It has a simple structure, making maintenance easier. It is widely used in operations such as gas absorption, distillation, and extraction.
From a mass transfer perspective, the mass transfer performance in a packed tower is the best. In particular, the use of new types of structured packing results in a higher mass transfer efficiency compared to other tower types. But aren’t packed towers seen in large-scale distillation, absorption, and desorption processes?
The former has a lower cost, offers certain operational flexibility in terms of steam and load, and has lower requirements regarding the fluids used； The latter requires a higher liquid flow rate, a lower pressure drop, and has a greater processing capacity; it is not suitable for liquids containing particulate impurities.