Hydrometallurgy Wastewater Split-Up by Fluidized-Bed Ion-Exchange Continuous Equipment

ABSTRACT

A proposed operation of a semicontinuous fluidized-bed ion-exchange system was studied. The system splits a liquid current into two currents, one being more concentrated and the other more depleted. This operating technique has been used to split up a mixture of alkaline ions (Na⁺, K⁺) using a strongly acidic resin. The equipment operates simultaneously in two multistage columns, one for loading and the other for elution of the resin. The experimetal testing system employs a hydrometallurgy wastewater containing cobalt and copper as heavy metallic ions, and the resin used was of the chelating iminodiacetic type, Lewatit TP-207. At cyclic steady state, the equipment can split up the wastewater, producing an effluent concentrated in cobalt in the outlet stream of the loading column, and a concentrated stream of copper in the effluent of the elution column. The hydrodynamics and approach to the stationary state of the system were analyzed, and the selective recovery of metals was subsequently tested experimentally. This behavior presents certain similarities with a parametric pumping operation of the system, with the two columns operating at different pH values or temperatures.

Key Words::

• Ion exchange
• Fluidized bed
• Hydrometallurgy wastewater
• Split-up
• Iminodiacetic resin