Method for the re-treatment of residue generated from the removal of fluorine dissolved in waste water.

摘要

A method for the re-treatment of residue generated in the course of removing fluorine from waste water. The method comprises the step of: obtaining rare earth fluorides from the residue which is generated in the course of treating the waste water with a rare earth compound to remove fluorine ions from the waste water; and heat treating the rare earth fluorides at temperatures ranging from approximately 400 to approximately 1,300 DEG C for times ranging from approximately 0.5 to approximately 15 hours, after drying the rare earth fluorides. The invention pertains to the reuse of rare earth elements used in the treatment of fluorine. Products obtained by carrying out the method contain rare earth oxides, rare earth fluorides and rare earth oxyfluorides alone and the mixture thereof, which are useful as materials for general abrasive and as adding agents for T.V. Braun tube or for glass valve.