| 摘要 |
<p>PROBLEM TO BE SOLVED: To remove nitrate nitrogen contained in underground water, or the like, by blowing gaseous hydrogen into the water containing nitrate ions and electrochemically converting the nitrate ions to gaseous nitrogen on a catalyst under reducing conditions. SOLUTION: Water containing nitrate ions is pre-heated in a warming apparatus 1, a small amount of gaseous hydrogen is blown into the water in a gaseous hydrogen mixing and saturating apparatus 2 and the water is saturated with hydrogen by high-speed stirring to adjust the redox potential of the hydrogen- saturated water below that of water. In a denitrifying apparatus 3, the water is irradiated with short wavelength light such as UV on a catalyst under reducing conditions, electric current is supplied between electrodes and electromagnetic field conversion is carried out to excite and react the nitrate ions and hydrogen atoms and the nitrate ions are reduced and discharged as gaseous nitrogen into the air. The water freed of nitrate nitrogen is sent to a treated water oxidation acclimation apparatus 4, where oxygen is blown into the water in the reduced state to convert and acclimate to an oxidized state. In this way, the nitrate nitrogen included in underground water, or the like, is removed.</p> |
