A vertically oriented co-current contacting system, including: a vertically oriented co-current contactor (702, 703, 801, 802, 803, 902) located in-line within a pipe, the vertically oriented co-current contactor including: a vertically oriented mixer (706, 706A-B, 808A-C, 908, 1000), including: an annular support ring configured to maintain the vertically oriented mixer within the pipe, the annular support ring having a hollow space disposed therein; a number of radial blades extending from the annular support ring, the number of radial blades being configured to include flow channels connected to the hollow space to allow a liquid stream to flow into the number of radial blades; a plurality of liquid injection orifices (918, 1008) placed on the number of radial blades and configured to allow the liquid stream in the flow channels to be distributed in a gas stream (710, 806, 906); and a central gas entry cone supported by the number of radial blades and configured to allow the gas stream to flow into the vertically oriented mixer, wherein the number of radial blades include gas exit slots that allow the gas stream to be flowed out of the central gas entry cone, the gas exit slots being connected to the hollow section to allow a portion of the gas stream to flow through the number of radial blades; and a vertically oriented mass transfer section (708, 810A-C, 910) downstream of the vertically oriented mixer; wherein the vertically oriented mixer and the vertically oriented mass transfer section provide for efficient incorporation of liquid droplets formed from the liquid stream into the gas stream, and wherein the liquid droplets include impurities from the gas stream; and a separation system (704, 718, 804, 922) configured to remove the liquid droplets including the impurities from the gas stream. a vertically oriented mixer (706, 706A-B, 808A-C, 908, 1000), including: an annular support ring configured to maintain the vertically oriented mixer within the pipe, the annular support ring having a hollow space disposed therein; a number of radial blades extending from the annular support ring, the number of radial blades being configured to include flow channels connected to the hollow space to allow a liquid stream to flow into the number of radial blades; a plurality of liquid injection orifices (918, 1008) placed on the number of radial blades and configured to allow the liquid stream in the flow channels to be distributed in a gas stream (710, 806, 906); and a central gas entry cone supported by the number of radial blades and configured to allow the gas stream to flow into the vertically oriented mixer, wherein the number of radial blades include gas exit slots that allow the gas stream to be flowed out of the central gas entry cone, the gas exit slots being connected to the hollow section to allow a portion of the gas stream to flow through the number of radial blades; and an annular support ring configured to maintain the vertically oriented mixer within the pipe, the annular support ring having a hollow space disposed therein; a number of radial blades extending from the annular support ring, the number of radial blades being configured to include flow channels connected to the hollow space to allow a liquid stream to flow into the number of radial blades; a plurality of liquid injection orifices (918, 1008) placed on the number of radial blades and configured to allow the liquid stream in the flow channels to be distributed in a gas stream (710, 806, 906); and a central gas entry cone supported by the number of radial blades and configured to allow the gas stream to flow into the vertically oriented mixer, wherein the number of radial blades include gas exit slots that allow the gas stream to be flowed out of the central gas entry cone, the gas exit slots being connected to the hollow section to allow a portion of the gas stream to flow through the number of radial blades; and a vertically oriented mass transfer section (708, 810A-C, 910) downstream of the vertically oriented mixer; wherein the vertically oriented mixer and the vertically oriented mass transfer section provide for efficient incorporation of liquid droplets formed from the liquid stream into the gas stream, and wherein the liquid droplets include impurities from the gas stream; and a separation system (704, 718, 804, 922) configured to remove the liquid droplets including the impurities from the gas stream.