The influence of wettability on the equilibrium wall flow of liquid in a packed column

It is well known that when a packed column is irrigated by a liquid and is operated in the trickle flow regime, part of the liquid flows preferentially along the column wall. The liquid distribution reaches equilibrium if the column is tall enough. In the present study the equilibrium wall flow in a column packed with rasching rings was studied experimentally. The effects of the wettability of the wall and the packing, and the total liquid flow rate on the equilibrium wall flow were investigated. It was found that the equilibrium wall flow depends strongly on the wettability of the wall, but is almost independent of the wettability of the packing. These results were used to gain some insight into the mechanism of the development of wall flow in packed columns.