摘要
从综合回收去除法的角度出发,讨论如何降低钽铌湿法冶炼过程中产生的废水水体中氨氮氟的浓度,回收氨或铵盐,尽量减少氨、氟、硫酸根离子的排放.对钽铌湿法冶炼过程中产生的废水进行了调研,分析了分类处理钽铌湿法冶炼产生各种浓度、酸度废水的方法:(1)对高酸废水采用生石灰(CaO)中和,可完全去除氟、硫酸根离子.(2)对中低浓度含氨、氟、硫酸根废水采用生石灰沉淀—蒸馏法回收氨水的方法进行了实验研究,处理后的废水中氨的含量小于25mg/L,达到废水排放标准.(3)对高浓度含氨、氟、硫酸根废水采用蒸发结晶、热分解、冷凝吸收制取NH3·H2O,NH4HSO4,NH4HF2,有效地降低了废水中的氨、氟.通过高浓度含氨废水实验证明:制取的NH3·H2O,NH4HSO4,NH4HF2完全可以返回钽铌工业使用,具有较好的环境和经济效益.
How to reduce the concentration of SO42-, F-, NH4+ in Ta/Nb h ydrometallurgy waste water so as to recover ammonia and ammonium salts is discus sed. Sorts of waste water are classified and disposed. The acid waste water is d isposed by CaO precipitation, but decreasing the removal of SO42-, F-and NH 4+ . The basic waste water in small concentration SO42-, F-, NH4+ is disp osed by CaO precipitation and distillation method. The waste water containing NH 4+ beyond 25 mg/L is qualified by drainage. The waste water in high concentrat ion SO42-, F-, NH4+ is disposed by crystallizing evaporation, decompositio n, and condensation. NH3· H2O,NH4HSO4,NH4HF2 are recovered and reused in Ta/Nb metallurgy. The experiment shows: the disposal of Ta/Nb hydrometallurgy waste wa ter is much more economic and has higher environmental value.
出处
《宁夏工程技术》
CAS
2003年第3期235-238,共4页
Ningxia Engineering Technology
