A COMPARATIVE ECONOMIC-ANALYSIS OF COPPER REMOVAL FROM WATER BY LIGAND-MODIFIED MICELLAR-ENHANCED ULTRAFILTRATION AND BY CONVENTIONAL SOLVENT-EXTRACTION

In ligand-modified micellar-enhanced ultrafiltration (LM-MEUF), a surf actant and a ligand are added to an aqueous solution containing ions o f like charge. The ligand forms a complex with the target ion of inter est and becomes incorporated in the micelle. This solution is then tre ated by an ultrafiltration process with membrane pore sizes small enou gh to reject the micelles and their solubilized metal-ligand complex. Previous studies have demonstrated the technical feasibility of LM-MEU F with copper rejection exceeding 99% with no removal of calcium using several different Ligands. The ability to regenerate the surfactant/l igand for reuse has also been shown. In this study, an economic analys is of LM-MEUF (with regeneration) for a 1x10(5) gal/day unit is report ed. The effects of important parameters are investigated; including fe ed surfactant, ligand, and copper concentrations. The results from the sensitivity analysis are used to compare the cost of LM-MEUF for copp er removal and recovery to the conventional copper solvent extraction process. The comparative economic analysis indicates a 17% higher capi tal and a 43% higher operating cost for LM-MEUF process compared to th e solvent extraction process. (C) 1998 Elsevier Science B.V.