Abstract: A gas-liquid contacting tray suitable for horizontal mounting in a normally vertical column, which tray comprises a tray plate with substantially circular circumference and having top and bottom surfaces, which tray plate is provided with passages for gas between the bottom and the top two semi-circular tray sections are defined by a virtual diametrical line of the tray plate; and a total the tray plate to below the tray, of three downcomers for guiding each downcomer extending from an inlet opening arranged in the tray plate to a downcomer outlet opening below the tray, wherein two of the downcomers are arranged in the corners of one of the semi-circular tray sections, and wherein the third downcomer is arranged on the other tray section substantially along a radius of the tray that is perpendicular to the diametrical line.