Operation of Integrated Column Leach and Solvent Extraction Circuit for the A-Cap Resources Letlhakane Deposit

摘要

ANSTO Minerals recently completed a program of work testing the proposed flow sheet of the A-Cap Resources Letlhakane uranium deposit in Botswana. Over two campaigns, heap leach columns were fully integrated with a solvent extraction circuit to strip the uranium and recycle the raffinate to the heap leach column.This presentation will describe the complexities of operating an integrated column leach and solvent extraction operation. Given the high organic carbon content of the Letlhakane ore, the likelihood of preg-robbing in the heap leach was a consideration in the selection of the column operating conditions. Brannerite was the only uranium-bearing mineral conclusively identified by QEMSCAN in the ore samples. Mineralogy on the column ripios showed the remaining uranium to be finely entrained with rutile and zircon. Bottle roll and diagnostic leach tests were subsequently completed on the ripios to determine whether further uranium recovery could be achieved.