诱导结晶工艺处理含铜废水

Copper removal by induced crystallization from copper-containing wastewater

利用诱导结晶法处理浓度为20、50、100 mg.L-1的含铜废水,稳定运行后去除率皆能达到90%以上。实验连续运行145 d,定期取出结晶产物,通过SEM-EDS测试发现:结晶颗粒逐渐长大,其组成为碱式碳酸铜,分子式推测为CuCO3.Cu(OH)2.xH2O。本文还考察了沉淀剂种类、进药比、水力负荷以及停留时间对诱导结晶工艺处理含铜废水的影响。结果表明:当废水中[Cu2+]为20 mg.L-1时,最佳运行条件为:以碳酸钠为沉淀剂,进药比在1～2,水力负荷不高于25 m.h-1。停留时间对结晶工艺的影响不大。

Induced crystallization is employed to treat copper-containing wastewater in this study. The copper removal efficiency can be achieved to 90% when the influent copper concentration is 20 mg · L^-1 , 50 mg · L^-1 , 100 mg · L^-1. For a 145 d experiment, it can be found a noticeable crystal growth, which can be speculated as alkaline copper carbonate ECuCO3 · Cu （OH）2 · xH2O）] as measured by SEMEDS. Optimized conditions for copper removal efficiency were investigated by varying the type of chemical reagents, the molar ratio of CT to Cu, the hydraulic loading and the hydraulic retention time. The best results were obtained when the chemical reagent is Na2CO3, the molar ratio of CT/Cu is 1-2, and the hydraulic loading is not higher than 25 m · h^-1.