Removal and Recycling of Fluoride from Wastewater from a Nonferrous Metallurgy Plant

This study investigated the effect of different variables on fluoride removal from wastewater from a nonferrous metallurgy plant. The results indicate that the residual fluoride concentration of the filtered solution was lower than 8 mg/l when the optimum conditions were used, where the process was performed at 35 degrees C for 40 min, the quantity of seed crystals was 10 g/l, and the excessive calcium concentration was 300 mg/l in the solution. Actual treatment performance for the effluent was tested, and the fluoride concentration fulfills the industrial discharge standard of China. The contents of calcium fluoride obtained were 95.86% and 96.52%, respectively, by chemical analysis and XRF. The particle size distribution was from 1.558 mu m to 35.235 mu m. It is also feasible to recycle calcium fluoride by the induced crystallization process.

Automated summary

This study investigated the effect of different variables on fluoride removal from wastewater from a nonferrous metallurgy plant. The results indicate that under the optimum conditions, the residual fluoride concentration was below 8 mg/l, meeting the industrial discharge standard of China. It is feasible to obtain high purity calcium fluoride through chemical analysis and XRF.