Abstract: A liquid-vapour contact column includes an array of vertically spaced horizontal liquid-vapour contact trays having generally circumferential sides and arrangement of downcomers to conduct liquid from each tray in the array to the tray below. Each tray has gas passages to enable gas to pass into contact with the liquid. A weir is disposed on the floor of at least one downcomer. Each side of the weir is spaced from the corresponding side of the downcomer. This arrangement counteracts a tendency for liquid flowing along the floor of the downcomer to become detached from the sides of the downcomer, such detachment leading to maldistribution of liquid on the tray and hence to less efficient operation of the column.

Abstract: A liquid-gas contact device comprising a liquid-gas contact tray comprising a multiplicity of the elongate apertures in the tray for the passage of gas from below to above the tray, each aperture having a gas deflector associated therewith in being so disposed as to impart to the gas a component of velocity in the general direction of liquid flow, and at least several liquid flow in impedance members arranged so as to control the liquid velocity on the liquid-bearing surface to prevent it from reaching so great a magnitude that the residence time of liquid on the tray is insufficient for adequate gas-liquid contact to take place. Preferably the tray comprises a sheet of expanded metal.