ION-EXCHANGE IN A SEMIFLUIDIZED BED

Removal of copper ions from electroplating wastewater by ion exchange in a liquid-solid semifluidized bed is-studied. The column diameter an d height of the semifluidized bed is studied. The column diameter and height of the semifluidized bed are 8.1 and 150 cm, respectively. CuSO 4 solution is used as the synthetic wastewater, and Amberlite 200C res ins are employed as the ion-exchange resins. It is found that the effl uent Cu2+ concentration of the semifluidized bed increases as the liqu id volumetric flow rate or feed concentration is increased. Moreover, the height of the fluidized bed section keeps decreasing during the io n-exchange process. A mathematical model is developed to describe the ion-exchange process in the semifluidized bed satisfactorily. A compar ison of the performance of the semifluidized bed, the fluidized bed, a nd the packed bed based on the treatment efficiency is also made. It s hows that the treatment efficiency is the highest for the semifluidize d bed.