A liquid mixing collector includes first and second sump zones, a first and optionally a second liquid collection region, first and second interspersed sets of spaced apart liquid collection channels positioned in the first liquid collection region, the first and second sets of collection channels being associated with the first and second respective sump zones, wherein adjacent liquid collection channel sets are vertically displaced in parallel horizontal planes. The invention also relates to the process of using the collector within a heat or mass transfer column.