Leaching Agglomerated Gold-silver Ores.
Heinen-HJ; McClelland-GE; Lindstrom-RE
U S Pat 4 256 705 1981 Mar; :
Gold or silver ores, tailing, or wastes are treated by agglomerating the fines by means of a binding agent and water, aging, and percolation leaching to recover au or ag values. Calcium oxide and portland cement are efficient as binding agents at 5-15 lb/ton of feed and 8-16 pct water. Aging time was 5-72 h, and leaching was done with a solution containing 2 lb nacn/ton of feed. Thus, tailings containing 2.8 Oz/ton ag (30 pct -100 mesh) were mixed with 5 or 10 lb/ton cao and agglomerated with 9 pct h2o. The agglomerates were aged for 24 h and leached by percolating with the nacn solution. The flow rates were 6 and 8.5 Gal/h-ft2 for the amounts of cao, respectively, and ag recovery was 95 pct.
U.S. Pat. 4,256,705, Mar. 17, 1981; Chem. Abstr. 94:87,870W