Could the experts please tell me what data is required to simulate the absorption process in PROⅡ?

The distillation model can be used; the number of trays can be defined arbitrarily, no condenser or reboiler is needed, and there is no need to calculate the tower height and diameter first.

First, the calculation of process parameters is carried out; only after everything is determined are the hydraulic calculations for tower diameter and height performed. Since the number of plates, heat load, and separation requirements are in a functional relationship with one another once the feedstock is determined, if calculations are performed under given values for the number of plates and separation requirements, the result may be an excessive heat load (which is a function of the reflux rate), meaning it is not economical. I recommend that, once the requirements for raw materials and separation are determined, the number of plates should be adjusted continuously to find a functional relationship between the number of plates and the heat load, thereby achieving economic optimization. Once the number of plates is determined, an appropriate plate spacing is chosen based on the vapor-liquid flow rate load, and at that point the tower height is also determined. Once the reflux rate is determined, that is, once the heat load is fixed, the amount of steam rising is also determined. At this point, by specifying an appropriate F factor, the tower diameter can be determined as well. The hydraulic calculation of towers is not very difficult, but achieving the right design is not easy; sometimes we see towers with varying diameters because the vapor-liquid loads in different sections of the tower are different.

Double-click to open the distallation model you have created; click on \"tray hydraulics\" in the upper middle part on the left to enter the hydraulic input window.

Reply to 5# wss20011: I’m sorry; I’m just new to this software. I work with padding absorption, and isn’t it necessary to use shortcuts first?

I usually don’t use the shortcut model; instead, I use distillation with a relatively large number of layers, and then reduce that number during the optimization process. Both packed columns and tray columns are initially calculated using theoretical plates; the difference is that the actual number of trays in a tray column equals the theoretical number of plates divided by the tray efficiency, while the height of a packed column equals the theoretical number of plates multiplied by the equivalent plate height.

A shortcut is to use the optimal number of theoretical plates required for such separation tasks as a preliminary value.