An apparatus for collecting and redistributing a flow of a liquid descending in an exchange column containing a layer of packing extending across at least a portion of the cross-sectional area of the exchange column, comprising: a plurality of laterally spaced apart support grates, including at least one pair of support grates comprising a first support grate and a second support grate laterally spaced apart from the first support grate, said support grates to extend across at least a portion of the cross-section area of the exchange column, and each support grate having at least one inner side, an upper end for location adjacent to the bottom of the layer of packing and a lower end opposite the upper end; a plate for location in vertically spaced apart relation from the bottom of the layer of packing and to extend across at least a portion of the cross-sectional area of the exchange column to collect liquid descending in the exchange column, said plate having a first end and a second end opposite the first end, the first end of said plate connected to the inner side of the first support grate and the second end of the plate connected to the inner side of the second support grate to extend between said opposed ends thereof to collect liquid descending therebetween, wherein said support grates extend upwardly from said plate and wherein said plate is connected to each support grate by welding or other fastening means; and at least one vapor riser projecting upwardly from the plate between said first and second support grates to receive and transmit vapor through the plate, the vapor riser having a cap, at least one upright wall connected to the plate and projecting upward above the plate and connecting to the cap, and at least one opening adapted to transmit at least a portion of the stream of the vapor outward from the vapor riser. a plurality of laterally spaced apart support grates, including at least one pair of support grates comprising a first support grate and a second support grate laterally spaced apart from the first support grate, said support grates to extend across at least a portion of the cross-section area of the exchange column, and each support grate having at least one inner side, an upper end for location adjacent to the bottom of the layer of packing and a lower end opposite the upper end; a plate for location in vertically spaced apart relation from the bottom of the layer of packing and to extend across at least a portion of the cross-sectional area of the exchange column to collect liquid descending in the exchange column, said plate having a first end and a second end opposite the first end, the first end of said plate connected to the inner side of the first support grate and the second end of the plate connected to the inner side of the second support grate to extend between said opposed ends thereof to collect liquid descending therebetween, wherein said support grates extend upwardly from said plate and wherein said plate is connected to each support grate by welding or other fastening means; and at least one vapor riser projecting upwardly from the plate between said first and second support grates to receive and transmit vapor through the plate, the vapor riser having a cap, at least one upright wall connected to the plate and projecting upward above the plate and connecting to the cap, and at least one opening adapted to transmit at least a portion of the stream of the vapor outward from the vapor riser.