Techno-economic comparison of technologies for the concentration of a mixed leachant bleed stream

In a new hydrometallurgieal process for recovery of lead from lead oxide secondaries, liquid effluence is minimized by jointly treating contaminated was~ting water and leaehant bleed. To enable internal recycling of the leachant bleed and recover pure water, it is necessary to incorporate a concentration unit. In this paper different technologies for concentrating the mixed stream are compared. At a specified water recovery rate of 10 m3/h, the total costs for mechanical vapour compression evaporation, freeze concentration and multiple effect evaporation are 13, 18 and 18 U$/ra 3 of recovered water, respectively. The total costs decrease at ~ncreasing water recovery rates, but mechanical vapour compression evaporation remains gie cheapest technology w:,thin the major part of the range studied (5-55 m3/h water recovery).