The solute-containing gas, or rich gas, enters the distributing space below the packing and flows upward trough the interstices in the packing countercurrent to the glow of the liquid. The packing provides a large area of contact between the liquid and gas encourages intimate contact between the phases. The solute in the rich gas and absorbed by the fresh liquid entering the tower, and dilute, or lean, gas leaves the top. The liquid is enriched in solute as it flows down the tower, and concentrated liquid, called the strong liquor, leaves the bottom of the tower through the liquid outlet.