Techno-economic analysis of integrating liquid membrane with electrowinning for copper recovery from electroplating wastewater

Liquid membrane is a prospective technology for the separation and preconcentration of metal ions from their diluted aqueous solutions prior to solid metal recovery by traditional electrowinning. To examine the technical and economic viability of integrating liquid membrane and electrowinning systems, a techno-economic analysis was conducted for a newly developed process consisting of a continuous bulk liquid membrane (CBLM) with an electrowinning cell for copper recovery from electroplating wastewater. A commercial steady-state process simulation software, SuperPro Designer v.12.3, was used for simulation and economic evaluation of the integrated CBLM-electrowinning process, based on data derived from a laboratory experiment scale-up. Three different membrane solvents, i.e. fresh vegetable oil-, waste vegetable oil (WVO)-, and kerosene-based types, were studied at various recycle rates to determine optimum membrane solvent. Before the economic performance was considered, kerosene-based solvent reported the best recovery of copper from wastewater. With economic evaluation, the WVO outperforms the other solvents, as it is available free of charge from collected waste oil, despite having the lowest revenue among all solvents. The economic analysis indicated that CBLM with WVO-based membrane solvent at 99% of membrane solvent recycle rate was the most viable with a net expenditure of $ 0.161 MM/y.