Changgiakou carbonaceous shale ore gold oxide, gold mainly occur in natural brown iron pyrite, white lead, galena, yellow copper ore and quartz, flotation concentrates produced by the carbon-containing argillaceous And the higher the carbonate, the recovery rate of cyanide leaching gold is 85%. In order to improve the recovery rate of gold, we have separately explored several process tests of direct leaching of thiourea on concentrate and leaching after decarburization. The recovery rate of gold is still only 80%, while the consumption of thiourea is more than 5kg ,t, sulfuric acid consumption. Up to 130 ~ 180kg ∕t. To this end, a small oxidative roasting study of concentrates was carried out. The industrial test conducted according to the results of the small test was to oxidize and roast the concentrate at 680 ° C for 20 min. The test proves that both the calcination and the roasting are combined. Calcination decomposes the carbonate and the limonite loses the water of crystallization; the combustion is carried out to remove the sulfur and carbon cyanide. The carbon content of the calcine produced is reduced to less than 0.08%. The calcined sand is further leached with thiourea. The recovery rate of gold is increased from 72% to 85% before calcination to 94% to 96%, the consumption of thiourea is reduced to 1.5 to 2.2 kg ,t, and the sulfuric acid is reduced to 70 kg/ t. Machine Embroidery Designs,Embroidery Sewing Machine,Hat Embroidery Machine,Computer Embroidery Designs Ningbo World Wide Electric techonology CO.,Ltd , https://www.mysewmachine.com
April 25, 2023