| 摘要 |
<p>A method for vacuum deaeration of a dissoved gas in a pure water, the pure water having a specific resistivity of not less than 0.1 M OMEGA .cm, in a vacuum degasifier column (1) maintained at a pressure slightly higher than a saturated steam pressure at a temperature of the pure water, the column having a region filled with packings (3), spraying (7) the pure water downwardly from above the region and meantime evacuating (5) inside the column to maintain the pressure, the method comprising the steps of: carrying out the evacuation from above the region to maintain a pressure made by adding 1 mmHg to 10 mmHg to the saturated steam pressure at the temperature of the pure water inside the vacuum degasifier column; and introducing an inert gas (11) upwardly from below the region at a volumetric flow rate in the range of from 0.001 to 1.0, based on the volumetric feed flow rate of the pure water taken as 1, simultaneously with the evacuation, to lower a dissolved oxygen concentration in the pure water below 10 ppb. <IMAGE></p> |
