Advances In Continuous Vat Leaching Technology

Since the production prototype continuous vat leaching pilot plant was installed at Ariel Resources in Costa Rica in 1995, the test results and lessons learned have been invaluable in plotting the future of this method. Vigorous test programs in base and precious metals as well as design developments for studies have shown the advantages, economically, technically, and environmentally that favor this method over current practices in heap leaching and stirred tank leaching. Much larger individual vats have been developed with throughputs as high as 5000 t/d with larger vats envisaged, and there has been a trend towards using vats with ground ore. Five projects are slated to begin detailed engineering this year, three in precious metals and two in copper. Of particular interest to future producers is the ability to deposit d,y, detoxified tailings at a fraction of the cost of conventional methods. Proprieta,y work is ongoing which promises to eliminate the need for tailings dams when using other methods of processing such as flotation. This is of particular importance in light of dam failures around the world in recent years.