Fluorine-containing wastewater treatment method and fluorine-containing wastewater treatment apparatus

摘要

According to one embodiment, this water treatment method comprises: a step in which a calcium preparation and a mixed functional powder that includes calcium fluoride, calcium sulphate, and calcium phosphate are added to water to be treated in a reaction vessel (12) that has a reaction region (12A) and an overflow region (12B), and fluoride ions contained in the water to be treated are crystallised in a calcium fluoride state on the surfaces of the mixed functional powder; a step in which a filter aid layer (142) is formed on a filter (141) by supplying a filter aid to the filter; a step in which the water to be treated is caused to overflow from the overflow region (12B) in the reaction vessel (12) while a portion of the mixed functional powder including the extracted calcium fluoride is precipitated and separated; and a step in which the water to be treated which contains the remainder of the mixed functional powder including the extracted calcium fluoride is supplied to a solid-liquid separation device (14) and removed by filtering using the filter (141) and the filter aid layer (142) in order to obtain treated water.