杂质离子是影响含氟废水结晶沉淀的关键因素之一，为探究杂质离子（Al³⁺和Si⁴⁺）对含氟废水钙盐结晶沉淀过程的影响，提高含氟废水的处理效果，利用NaF和CaCl₂反应模拟含氟废水沉淀过程，结合Visual MINTEQ软件模拟、XRD表征和SEM-EDS测试，系统研究Al³⁺和Si⁴⁺对沉淀结晶浊度、残余氟离子浓度及沉淀产物特征的影响。研究结果表明，低浓度的Al³⁺和Si⁴⁺对氟化钙结晶沉淀和除氟效果影响较小。当Al³⁺质量浓度为200.00 mg/L时，碱性条件下反应产生氢氧化铝和冰晶石等杂质沉淀，导致反应浊度升高，残余氟离子浓度随pH升高而降低；当Si⁴⁺质量浓度为200.00 mg/L时，结晶沉淀产物中含硅杂质主要为石英和硅酸钙，最佳除氟条件为n（Ca）/n（F）=2.5、pH=9，此时，溶液中残余氟离子质量浓度为5.62 mg/L。SEM-EDS测试表明，沉淀产物呈块状团聚体，氟化钙与杂质产物嵌布关系复杂，分离难度较大。研究结果为实际生产工艺中复杂多离子含氟废水的处理及结晶产物的回收利用提供参考。

Impurity ions are one of the key factors affecting the crystallization and precipitation of fluorine-containing wastewater.In order to investigate the influence of impurity ions（Al³⁺ and Si⁴⁺） on the calcium salt crystallization and precipitation process of fluorine-containing wastewater and improve the treatment effect of fluorine-containing wastewater，the reaction of NaF and CaCl₂ was used to simulate the sedimentation process of fluorine-containing wastewater.Combined with Visual MINTEQ software simulation，XRD characterization，and SEM-EDS testing，the influence of Al³⁺ and Si⁴⁺ on the turbidity of precipitation crystallization，residual fluoride ion concentration，and precipitation product characteristics was systematically studied.The research results indicated that low concentrations of Al³⁺ and Si⁴⁺ had little effect on the precipitation and defluorination of calcium fluoride crystals.When the concentration of Al³⁺ was 200.00 mg/L，impurities such as aluminum hydroxide and cryolite precipitated under alkaline conditions，leading to an increase in reaction turbidity and a decrease in residual fluoride ion concentration with increasing pH.When the concentration of Si⁴⁺ was 200.00 mg/L，the silicon impurities in the crystal precipitation product were mainly quartz and calcium silicate，and the optimal defluorination conditions were n（Ca）/n（F）=2.5，pH=9.At this point，the residual fluoride ion concentration in the solution was 5.62 mg/L.SEM-EDS testing showed that the precipitate products were in the form of block aggregates，and the embedding relationship between calcium fluoride and impurity products was complex，making separation difficult.The research results provided reference for the treatment of complex multi ion fluorine-containing wastewater and the recycling of crystallization products in actual production processes.