For the design of the specific grids, the following points must be considered with regard to the load of the grid:
- Weight of packed bed
- Liquid hold up during operation
- Pressure drop of the gas flow in cases of parallel flow
- Installation loads
The support grid has to be constructed in a way that allows the unrestricted flowing of gases and liquids in the columns as much as possible. There is the possible complication of blocking the gas flow with unsuitable packing support, especially in the area between the support grid and the packed bed.
For the installation of the support grid there is a support ring, and from case to case, one or more intermediate support beams as necessary. Usually it is sufficient to put the support grid on the support ring without fixing it; however, for applications with high gas velocities, pressures, or flooding possibilities it is necessary to fix the support grid to the support ring.