Bed limiters are situated directly over a packed bed to prevent the movement or discharge of the packing. They are particularly necessary in such cases where the packing can experience uplift due to high gas loading or sporadic pressure surges. Additionally, they can be used to separate packings of different sizes to avoid mixing of the packings in the column.
Bed limiters are designed in a way that they do not disturb the steady state of the liquid distribution.
Depending on the model, bed limiters either sit directly on top of the packed bed, or they are mechanically attached to the vessel wall. It is also possible to hang them directly from the liquid distributor or re-distributor as well as integrate them directly into the design of the liquid distributor or re-distributor.