An economic and energy evaluation of the replacement of conventional technology with continuous chromatography in the dump leaching of copper ores

Abstract

The focus of this investigation is an economic and energy analysis of the implementation of CAC (continuous annular chromatography) to a large-scale industrial process. The technology selected is the dump leaching of copper and other metal values from low-grade copper ores. The portion of the presently used process to be placed in this case is the solvent extraction (SX) train in which the copper in solution is separated from the leach liquor from dump leaching. Instead of SX, we use the CAC for the separation and immediately obtain two advantages: (1) We can separate all of the metals such as iron, cobalt, and yttrium as well as copper in one operation, thus reducing the plant size and increasing the total metal values recovered; and (2) we exit with purer and more concentrated steams, thus improving the energy and economic picture. To scale the CAC, we have developed a model for the process which is implemented in ASPEN (Advanced System for Process Engineering). Modules for both the mass/energy balance part and the economics were implemented in ASPEN. ASPEN is a state-of-the-art process simulator which was originally written for the Department of Energy to be used in evaluating processes which are similarmore » to the one we are considering. It allows one to perform the most complex material and energy balances automatically and to tie these in the same simulation to the economic evaluations of the process in question. Our implementation is an advanced version of the simulator, is distributed by JSD Associates.« less