七铝酸十二钙对水中硫酸根的去除研究

Study on Sulfate Treatment in Water by Mayenite

以Al2O3和CaCO3为原料采用高温煅烧法制备了七铝酸十二钙(Ca12Al14O33),用该药剂处理含SO42-水溶液,确定了使出水SO24-浓度降至250mg/L以下的处理条件,并考察了水中Mg2+、Fe3+、SiO23-对处理效果的影响。结果表明,在投药量为2g/L、搅拌时间为20min时,七铝酸十二钙去除SO42-的效果最佳,可将其从1000mg/L降至250mg/L以下。适量加入铁离子可增强药剂的絮凝效果,提高其对SO24-的去除能力;而镁离子和硅酸根离子则可减弱七铝酸十二钙对SO42-的去除能力。

Mayenite （Ca12Al14O33） was prepared by calcining Al2O3 and CaCO3 under high temperature. The mayenite was used to treat the aqueous solution containing sulfate, the optimal treatment conditions to reduce the sulfate concentration to lower than 250 mg/L were determined, and the effects of Mg^2＋ , Fe^3＋ and SiO3^2- on treatment efficiency were investigated. The results show that under the condi- tion of mayenite dosage of 2 g/L and stirring time of 20 min, the best removal effect of sulfate can be received, and its concentration can be reduced from 1 000 mg/L to 250 mg/L. The flocculation effect of the mayenite can be enhanced, and the sulfate removal ability can be improved when adding feasible quantity of iron ion. Magnesium ion and silicate can reduce the sulfate removal ability of the mayenite.