离子型稀土冶炼废水资源回收及达标排放处理工艺研究

Technology analysis for resource recycles and standardized discharge of ion-absorbed rare earth mineral wastewater

离子型稀土冶炼废水水质成分复杂,NH_3-N浓度极高,直接排放不仅造成严重的环境污染而且形成巨大的资源浪费。通过全面分析稀土冶炼废水水质,对稀土冶炼废水资源回收及达标排放处理进行了工艺理论分析,并提出了整套工艺流程。实验室小试及中试研究结果显示,该工艺能有效地从稀土冶炼废水中回收农业级NH_4Cl,并使废水达到污水综合排放标准(GB 8978-1996)的要求。

The components are very complex and NH3-N concentration is very high in ion-absorbed rare earth smelt wastewater. The serious environmental pollution and resource wasting would be caused if the wastewater is discharged directly. The characteristics of ion-absorbed rare-earth smelting wastewater are analyzed detailed and process and technology of rare-earth smelting wastewater treatment are discussed in this paper. The flow chart of process for ion-absorbed rare-earth smelting wastewater treatment resource recycles is designed. The results of laboratory and pilot-scale experiments showed that the NH4Cl products could be obtained, which can be used in agriculture. The effluent achieves the discharge standard of GB 8978-1996.