Patent ID: 6210589
Filing Date: 2001-04-03
Classification: D01F,Y10S

Abstract:
A process for removing fluoride from wastewater, comprising the following steps of:(a) introducing a first fluoride-containing wastewater into a first fluidized bed crystallizer having first carriers inside; and(b) adding a first water soluble calcium reagent, sodium reagent and aluminum reagent into the first fluidized bed crystallizer to form pachnolite on the first carriers so as to remove fluoride from the first fluoride-containing wastewater and obtain a primary treated water, wherein the molar ratio for calcium:aluminum:fluoride in the first fluidized bed crystallizer is 0.8-1.2:0.8-1.2:6.0 and the molar ratio of sodium to fluoride in the first fluidized bed crystallizer is greater than 1/6.