PROCESS FOR REMOVAL AND REMOVING AGENT OF FLUORINE ION

摘要

PROBLEM TO BE SOLVED: To provide a process for efficiently removing dissolved fluorine ions from the inside of water to be treated and for reducing the amount of the sludge to be generated. SOLUTION: The fluorine-containing water to be treated is settled and separated of its dissolved fluorine ions as hardly soluble substances by allowing harmless polyvalent metal ions to exist in the water to be treated, adding an alkali thereto to adjust the pH of the water to be treated to≥10, adding rare earth element ions thereto and further adding aluminum ions at need thereto, then adding an acidic substance thereto to adjust its pH to≥6 and <10. COPYRIGHT: (C)2004,JPO