| 摘要 |
PROBLEM TO BE SOLVED: To treat efficiently water containing fluoride ions F or calcium ions Ca and water containing F and Ca and prepare pure water. SOLUTION: Water containing Ca and F is passed through a cation exchange column 2 and then treated by an RO membrane separation device 3 to prepare permeated water (purified water). Or Ca containing water is treated by a cation exchange column, and F containing water is RO membrane separation treated. Concentrated water in the RO membrane separation device 3 is mixed with regenerated waste liquid in the cation exchange column 2 to separate CaF2 precipitation to prepare treated water. The pure water is prepared by using cation exchange resin to remove Ca, and separating F and other salts by an RO membrane. The pure water is discharged by regenerating the cation exchange resin. CaF2 is separated by mixing the regenerated waste liquid containing a large amount of Ca with concentrated water containing a large amount of F provided by the RO membrane separation treatment, and the regenerated waste liquid and the concentrated water can be treated easily to prepare dischargeable treated water. |
