膨润土复合颗粒制备工艺及其吸附性能研究

Experiment Study on the Preparation Process and Adsorption Property of Bentonite Composite Particle

针对矿山废水中酸度、重金属离子的高成本处理问题,采用经高温焙烧的膨润土-钢渣复合颗粒对Fe^(2+)、Mn^(2+)、Cu^(2+)和Zn^(2+)进行吸附。从去除效果、碱度释放量及散失率对复合颗粒的最佳制备工艺进行研究,并用其处理模拟酸性矿山废水(AMD)。结果表明,最佳制备工艺条件为:膨润土与钢渣配比5∶5,黏结剂用量5%,焙烧温度500℃,焙烧时间60 min;当吸附剂投加量为10 g/L,吸附时间为240 min时,酸性矿山废水中Fe^(2+)、Mn^(2+)、Cu^(2+)、Zn^(2+)的去除率分别为93.21%、87.31%、100%、89.68%,出水pH值为8.31。膨润土-钢渣复合颗粒可同步降低水中酸度,去除重金属离子,且处理成本较低,值得推广应用。

For the problem of high treatment cost of acidity and heavy metal ions in mine drainage, bentonite-steel slag composite particle calcined at high temperature was used to adsorb Fe2-, Mn2-, Cu2. and Zn2＋. The study on the best preparation of composite particle was carried out from the removal efficiency, the release of alkalinity and the lost ratios, and use it to dispose simulate AMD. Results showed that the optimum process conditions were as follows： the ratio of bentonite and steel slag is 5 ： 5, additive agent account for 5%, roasting temperature is 500℃, roasting time is 60 min. When adsorbent dosage was 10 g/L and adsorption time was 240 min, the removal rate of Fe2＋, Mn2＋, Cu2＋ and Zn2＋ in AMD were 93.21%, 87.31%, 100%, 89.68%, pH value of treated water was 8.31. Bentonite-steel slag composite particle is worthy to apply which can lower the cost, reduce acidity and remove heavy metal ions.