Recycling treatment method of fluorine-containing waste liquid

The invention provides a method for recycling fluorine-containing waste liquid. The method comprises the following steps: step 1, weighing a certain amount of fluorine-containing waste liquid containing ammonium fluoride; 2, calculating the mass of sodium chloride needing to be added according to a corresponding chemical equation; 3, dissolving sodium chloride, and adding the dissolved sodium chloride into the ammonium fluoride waste liquid to obtain a turbid reaction solution; 4, the reaction solution is filtered and then separated, a filter cake and filtrate are obtained, liquid obtained after the filter cake is washed with pure water is mixed with the filtrate, and mixed filtrate is obtained; 5, evaporating and concentrating the mixed filtrate until part of sodium fluoride is separated out to obtain a saturated ammonium chloride solution; and 6, adding a calcium chloride solution into the saturated ammonium chloride solution to generate calcium fluoride precipitate, centrifugally separating ...