模拟移动床连续处理含钙废水

采用模拟移动床技术,以天然斜发沸石为离子交换剂连续处理Ca~(2+)质量浓度为2000 mg/L的高钙废水。单柱实验表明:低流速、高温有利于吸附;低流速、高浓度再生剂(氯化钠)、高温条件下再生效果好。模拟移动床实验采用5根沸石柱串联组成的模拟移动床系统,稳定运行时,脱钙率高达99.6%,系统切换时间为80 min。吸附区为2柱串联,进液流速12 m/h,吸附温度90℃,切换周期钙平均质量浓度为7~9 mg/L。再生区3柱串联,进液流速为4 m/h,再生温度90℃,再生剂质量分数为15%,切换周期可得钙质量浓度为9~10 g/L的氯化钙和氯化钠混合溶液。

The Treatment of Calcium-containing Wastewater Using Simulated Moving Bed

Calcium-containing wastewater in which initial concentration of calcium was 2000 mg/L was treated by simulated moving bed continuously,using clinoptilolite as ion exchanger.The results of single-column experiments showed that lower flow rate and higher temperature were beneficial for adsorption,and higher concentration of regeneration agent (sodium chloride) promoted the regenerate.Simulated moving bed was consisted of 5 columns,of which 2 zeolite columns in series for adsorption and 3 zeolite columns for regeneration.The calcium remove rate was up to 99.6％ and switching time were 80 min while steadily running.The inlet flow rate was 12 m/h and temperature was controlled at 90 ℃ in adsorption zone,with 7～9 mg/L of average calcium concentration was obtained through switching cycle.9～ 10 g/L mixed solution of sodium chloride and calcium chloride through switching cycle was obtained under the operating conditions of 4 m/h of inlet flow rate at 90 ℃ in regenerate zone.Meanwhile,regeneration agent concentration was regulated about 15％.