| 摘要 |
PROBLEM TO BE SOLVED: To provide an easy and efficient method for treating waste water containing fluorine and boron by efficiently decompose hardly decomposable borofluoride ion. SOLUTION: After borofluoride ion is decomposed by adding a polyvalent metal salt 4 and a pH controlling agent 5 to the waste water 1 and radiating the water with ultrasonic waves, a calcium salt 7 and a pH controlling agent 8 are added to the water to convert fluorine into calcium fluoride. After a flocculant 10 is added to settle and separate the product, the water is passed through a boron adsorbing resin 12 to obtain final treated water 13. By radiating the waste water 1 with ultrasonic waves, decomposition of the borofluoride ion into boric acid and hydrogen fluoride is promoted, and the efficiency of sedimentation and removal by the calcium salt 7 is improved. |
