| 摘要 |
<p>A process for removing fluorine from water and for regenerating the filtration masses, characterised by:
- acidifying the crude water to be treated by injecting CO 2 ,
- adding sodium hypochlorite to protect the hydroxyapatite from the action of microorganisms,
- feeding the water into at least one filter filled with at least one layer of sand and at least one layer of hydroxyapatite,
- discharging the water to the outside,
- washing the interior of said filters by backwashing with water,
- feeding water containing Na(OH) through said filters from their bottom upwards to replace the F - ion with the OH - to restore the absorbent capacity of the hydroxyapatite,
- rinsing with a buffer solution in the form of water acidulated with CO 2 until the water leaving the top of the filter has a pH value equal to that of the buffer.</p> |
