TECHNOLOGY FOCUS - INORGANIC CHEMISTRY - Preferred Components: The second ammonium fluoride absorbing procedure comprises: delivering the silicon tetrafluoride gas reacted in the first absorbing tower incompletely to the second absorbing tower via the pipeline at a top part of the first absorbing tower, where the second absorbing tower uses 18-22 wt.% of ammonium fluoride solution as the absorbing fluid; controlling the temperature in the second absorbing tower at 60-80 degrees C; absorbing the silicon tetrafluoride gas gain; directly conveying the mixed fluid to the first absorbing tower as the absorbing fluid to use; and conveying the fluoride-contained tail gas absorbed by the second absorbing tower incompletely or the volatilized ammonium fluoride and ammonium fluorosilicate fluid foam to the third absorbing tower. The silicon tetrafluoride gas is largely absorbed and reacted in the first absorbing tower. The second absorbing tower obtains the mixed fluid of ammonium fluorosilicate and more than 70 wt.% of ammonium fluoride. The third section water absorbing procedure comprises: conveying the fluoride-contained tail gas absorbed by the first and second absorbing towers incompletely using water as the absorbing/washing fluid of the third absorbing tower; conveying the tail gas to the third absorbing tower and absorbing and washing it using water as ammonia escaped for overhigh temperature or the volatilized ammonium fluoride and ammonium fluorosilicate fluid foam to the third absorbing tower to obtain the mixed solution; compensating the mixed solution according to the mixture ratio of the required concentration of the animation; supplying the mixed solution in the 16-18% of mother liquor of the thinned ammonium fluorosilicate solution according to the mixture ratio of the required concentration of the animation; and performing the animation process after charging the liquid ammonia. The fluid phase and the solid phase of the ammonium fluorosilicate are separated by centrifuging step. The liquid ammonia is charged to perform the animation reaction treatment after mixing the separated fluid phase mother liquor with the mixture of the third absorbing tower. The animation reaction treatment comprises adding the mixed fluid of the third absorbing tower after properly cooling the ammonium fluorosilicate solution in the first absorbing tower, charging the liquid ammonia or the solid ammonium bicarbonate (NH4HCO3) to the animation reaction tower after evenly mixing the animation reaction tower, decomposing the thinned ammonium fluorosilicate solution using liquid ammonia or the solid NH4HCO3, controlling the temperature of the animation reaction treatment at 60-70 degrees C and the pH value of 7.5-8.5, charging the liquid ammonia and then mixing for 3-6 hours, obtaining the ammonium fluoride and the silica product with the concentration of 18-22%, delivering the product to a press filter to perform the liquid and solid separation, filtering the silica, obtaining 40% of ammonium fluoride solution by concentration. The ammoniation treatment comprises: cooling, crystallizing and separating the ammonium fluorosilicate solution in the first absorbing tower; dewatering the obtained solid phase ammonium fluorosilicate and making it to be the product of ammonium fluorosilicate, where the obtained 16-18% of thinned ammonium fluorosilicate fluid is mother liquor; adding the mixed fluid of the third absorbing tower in the mother liquor; obtaining 18-22% of ammonium fluoride solution and turbid liquid of silica according to the method after mixing the fluid in the animation treatment tower; processing the filter cake silica obtained in the process of separating ammonium fluoride and silica to be water glass or adding to the calcium superphosphate product; and directly returning the absorbing fluid to the first absorbing tower and the second absorbing tower using the filter fluid ammonium fluoride solution as the absorbing fluid. Most of ammonium fluoride solution is used as the starting point to prepare the other fluorine chemical industrial product after performing the animation reaction treatment is processed to be ammonium fluoride product or the ammonium fluoride solution. The absorbing fluid (18-20%) is prepared by concentration after adding water to the rest part of ammonium fluoride solution. The filter cake silica is processed to be the water glass or adding to the calcium superphosphate product.