Abstract: A horizontal pass, multiple packed-bed gas scrubber features relatively low pressure drop flow paths for both the gas flow and the scrubbing liquid flow, allowing large scale mass transfer of solute from the gas to the liquid. The scrubber is volumetrically compact, yet possesses extremely high scrubbing efficiency of large gas flow rates. Each packed bed comprises packing that is wetted by liquid emitted from low pressure drop orifices in piping near the top of the packing. The piping is supported by baffles that extend into the packing so as to force back into the packing any gas that seeks to avoid the packing by flowing through any void, or inadequately wetted, zone at the top of a bed.