The deaeration column is filled with high efficient structured packing. Its large internal surface ensures a maximal contact area between gas and liquid. Water is homogeneously distributed on the top and CO2/N2 is injected at the bottom of the column. While the water flows downwards through the packing, the CO2/N2 rises in counter-current removing the oxygen to concentrations as low as 10 ppb. A drive controlled pump maintains the level in the column and forwards the deaerated water into a buffer tank or point of use. This technology is distinguished by high efficiency and reliability and consumes just a fraction of energy compared to other methods.