A Feasibility Study of Wastewater Containing Pb(II) Recovery Using Electrodialysis Reversal

Lead is a highly toxic heavy metal. The investigation was conducted to remove Pb(II) from storage battery industry wastewater by using electrodialysis (ED) in laboratory. The storage battery industry wastewater has an initial Pb(II) concentration of 8.5 mg/L. The performance of ED is determined by a set of fixed and variable process parameters such as inlet concentration, operating current density, and operating flow rate. Like all the efficient ED operations, the process has to be optimized in terms of overall costs considering cell component designs and properties as well as all operating parameters. Under the conditions of operating current density at 3 A/cm2, liquid flow rate of 300 L/h and circulation time of 5~6, the Pb(II) concentration of storage battery industrial outlet wastewater can be reduced to below 0.01mg/L and the conductivity could be reduced below 10 s/cm. The treated water could be reused in the manufacture of storage battery. A mathematical correlationship of Jlim＝10.379V0.5324C, which described the characteristics of the equipment, was finally obtained. The results showed that Pb(II) wastewater of the storage battery industry could be effective treated by ED and the separation process presented several advantages such as highly selective desalination, high water recovery and the possibility of an intermittent operation. Operation cost of the EDR mini-plant was also estimated in this project. Total operation cost including electricity fee and chemical cost is about $0.102/m3 of treated water.