模拟移动床连续处理高浓度氨氮废水

以天然斜发沸石为离子交换剂，采用模拟移动床连续离子交换系统对2500 mg (NH4+)/L的模拟废水进行氨氮脱除研究，考察了氨氮去除的效果，以及沸石再生过程的影响因素。结果表明，由7根沸石离子交换柱组成的模拟移动床系统在稳定运行时，氨氮的去除率可达99.9%。系统操作条件为：系统的操作周期为15.17 h，切换时间为130 min，各区的进液流速都为6 m/h；再生区采用3柱串联，硫酸钠溶液为再生剂，再生温度为90℃，此条件下沸石的再生率达到88%；吸附区采用2柱串联，氨氮模拟污水常温进液，出水中氨氮质量浓度低于2 mg/L。此外，每切换周期可得14 L NH4+质量浓度为15.5 g/L的硫酸铵和硫酸钠混合液。

The Treatment of High Concentration of Ammonia Nitrogen Wastewater Using Simulated Moving Bed

Taking the clinoptilolite as adsorbing agent, continuous ion-exchange process of simulated moving bed was used to remove ammonium nitrogen from wastewater. The initial concentration of ammonium (NH4+) in wastewater was 2500 mg/L. The removal rate of ammonium and the inlfuence factors of zeolite regeneration were analyzed and discussed. The results showed that the simulated moving bed process consisting of seven columns could remove ammonium nitrogen with the efifciency up to 99.9% while steadily running. Operating parameters for process were as follows:switching interval was 130 min and the operation cycle was 15.17 h, feed rate was 6 m/h in all zones; regeneration zone was composed of three columns with sodium sulfate as the regenerat, the regenerative temperature was 90℃ and the regeneration rate of clinoptilolite reached 88%; adsorption zone was composed of two columns, the concentration of ammonium in the outlfow was reduced to 2 mg/L. In addition, each operate cycle would obtain 14 L of mixture solution of ammonium sulfate and sodium sulfate, the concentration of ammonium in the mixture solution was 15.5 g/L.