Patent ID: 6863267

Claim:
A column comprising a plurality of axially spaced trays with a distance of a tray space between the trays, in which each tray comprises: a bubble area; and a truncated rectangular downcomer sharing at least two boundaries with the bubble area, wherein the rectangular downcomer has a length and a width, wherein the length is longer than the width, and an upper end and a lower end, and wherein the truncated rectangular downcomer comprises: two sloped downcomer walls along the length; a downcomer opening at tray level; and, a downward directed liquid discharge openings at the lower end; wherein the truncated rectangular downcomer is so positioned on the tray that bubble area is present along the length, wherein the cross-sectional area at the lower end of the truncated rectangular downcomer is less than 40% of the cross-sectional area of the upper end of the downcomer at tray level, and wherein the truncated rectangular downcomer extends to between about 50 and 90% of the tray spacing below a tray; and wherein the truncated rectangular downcomer is arranged in a staggered arrangement in which each tray is divided into two tray sections by a diametrical line with each tray section provided with a row of the truncated rectangular downcomer arranged perpendicular to the diametrical line such that the ends of the truncated rectangular downcomer of each tray section meet the diametrical line in an alternating fashion; and wherein each tray section includes a segmented downcomer.