赤泥处理锌冶炼废水的研究

Study on the Treatment of Zinc Smelting Wastewater Using Red Mud

以赤泥为原料,通过静态实验方法研究了赤泥对模拟锌冶炼废水中Zn2+、Pb2+、Cd2+的吸附作用,以及焙烧温度、pH值、投加量、反应时间等因素对吸附的影响。结果表明,经600℃焙烧后的赤泥吸附效率较高,可作为一种有效的吸附剂和中和剂,尤其对Pb2+的吸附效果最为明显,且吸附处理后的赤泥沉降性能良好,易于固液分离。溶液pH值显著影响金属离子的去除效果,在近中性条件下吸附效果最好。赤泥对Zn2+的吸附可以用准二级动力学模型很好地模拟和解释,吸附过程以化学吸附为主。

Through static experiment method, with red mud as raw material to remove Zn^2＋ , Pb^2＋ and Cd^2＋ in the simulated zinc smelting wastewater, the influences of calcination tempera- ture, pH value, dosage and adsorption time on the adsorption were studied. Results show that the adsorption efficiency of the red mud baked at 600℃ was greatly increased. Therefore,the red- mud can be used as an effective adsorbent and neutralizer, and in particular, for adsorption of Pb^2＋ with improved removal effect. In addition, the settling rate of red mud after adsorption process was rapid, and the solid-liquid separation was easy. The solution pH affected the removal efficiency significantly, and red mud achieved the best removal in nearly neutral condition. It was found that a pseudo-second-order kinetics equation provided the best correlation to the data, and chemisorption played a leading role.