I would like to ask experts in tower technology: what are the main types of gas distributors for large-diameter towers?

I’ll take the lead here; I hope everyone will participate actively in the discussions

Gas-liquid distributor. The spiral nozzle type liquid distributor is a pressure-type liquid distributor with a high flow velocity of the liquid inside the tube. It is not prone to clogging the pipes or nozzles, and it has a relatively strong resistance to dirt and blockages. The tray-type gas-liquid distributor is a gravity-based liquid distributor that was developed to address the two major challenges of limited vertical space and clogging. Since the spray holes of this distributor are located in the upper middle part of the riser, the designed liquid level is generally about 100 millimeters above these holes. The heavy debris settles at the bottom of the tray, and a large amount of such debris can be stored in the space 200–300 millimeters above the small holes ； Light dirt floats on the surface of the liquid layer ； The pores in the liquid layer are difficult to block. It should be emphasized that when liquids are prone to polymerization such as auto-polymerization or polycondensation, the spray holes of the tray-type gas-liquid distributor can also become clogged. At this time, a spiral-nozzle type liquid distributor should be used

For large-diameter, tube-type gas distributors, the best method currently available is to use the variable mass approach for calculations. To ensure uniform distribution of the gas, each hole has a different size. The only drawback is that this approach results in higher resistance. For the detailed calculation process, please refer to relevant literature. This post was last edited by nanjingdaxue on 2009-3-13 at 21:26

The exit velocity in straight-tube designs is too high; a tubular arrangement can be used instead. For example, when it comes to distributing stripping steam, a tubular structure is employed, with the number and diameter of the distribution holes being controlled so that the exit velocity remains around 10 m/s. This design is simple in structure. There is also a type of gas distributor made using thin plates of about 1–2 mm thick, which are folded into multiple blades; these blades are arranged in a specific pattern and fixed above the inlet in the tower section, thereby enabling effective gas distribution. This type is suitable for pure gas phases. There are many other types of feeders designed for gas-liquid mixed phases, allowing for both liquid separation and gas distribution; the choice depends on the specific operating conditions

Today, many large-diameter towers use H-shaped feed distributors, while some also employ circular ones.

The selection of the distributor is mainly determined by the properties of the material, the type of distillation, and the operating conditions; the tower diameter should have little impact. For batch distillation, a tray type is recommended as it has a low height and offers great operational flexibility. For continuous distillation, inclined plate collectors and tray distributors are preferred.

There are mainly two types of gas-liquid distributors: (1) Pressure type—spray-type liquid distributor； (2) Gravity type—disk-type, trough-type liquid distributors

We used the spiral plate type, and the result is good

Gas distributors are mainly used at the point where materials enter the tower; there is no need to install them elsewhere. As long as there is a space of 400–500 mm, the gas can be distributed evenly a second time. For the distributor entering the tower, it is not necessary to install one if the gas velocity is not very high; however, it is required if the gas velocity is high. There is actually no need for a complicated design in the gas distributor; a simple tubular type will suffice. Processing is also simple.