Flotation and cyanide extraction of gold example 1
2020-09-07 11:02Introduction：Flotation and cyanide extraction of gold example 1 A gold beneficationplant in China deals with gold ore with quartzveins. The metal minerals are mainly pyrite, estradite, sphalerite, galena, pyrite, magnetite, silver gold ore and natural
Flotation and cyanide extraction of gold example 1
A gold benefication plant in China deals with gold ore with quartz veins. The metal minerals are mainly pyrite, estradite, sphalerite, galena, pyrite, magnetite, silver gold ore and natural gold.The gangue minerals are quartz, sericite, plagioclase, dolomite, hornblende, kaolin, etc.The natural gold is round, long and irregular in chalcopyrite, pyrite and quartz.The original ore contains about 10g/t gold and 0.1% copper.
· The plant adopts the combined process of flotation and cyanide gold extraction. After mixed flotation and separation flotation, gold and copper concentrate and gold-containing sulfur concentrate are obtained.Gold and copper concentrate contains gold of 500 ~ 1000g/t, containing copper of 4%, gold recovery about 50%, copper recovery about 50%.The gold - sulfur concentrate contains gold 80 ~ 100g/t, less than 0.1% copper, 35% ~ 40% sulfur, and gold recovery about 40%. The copper concentrate is sent to the smelter for treatment and gold sulfur concentrate grinding to 98% 200 mesh, pH value of 11, after the enrichment (adding flocculant) removing sodium xanthate flotation agent, NO. 2 oil and soluble salts, the underflow concentration about 25% ~ 30%.
· The gold content of gold sludge was 2% ~ 5%,after washing with sulfuric acid and drying and burning, add nitrates and borax as melt agents to melt the gold mixture into 40% ~ 50% gold alloy in the converter. The recovery of gold from smelting is 98% and the total recovery rate of gold is 85%.The material consumption (kg/t concentrate) of the treatment of gold-sulfur concentrate in this plant is: sodium cyanide 7.22, lead acetate 0.36, zinc wire 5.17, bleaching powder 6.95.
Because of the low concentration of copper ore,the plant has now been cancelled flotation separation operation, mixed flotation concentrate and then direct cyanidation extraction gold after grinding, and adopts two leaching two washing process, the second period of cyanide leaching pulp to send three layers thickener for solid-liquid separation and backwashing, the overflow pregnant solution back to the first cyanide leaching liquid countercurrent washing operation, sulfur powder export base through the vacuum filter.The first section of cyanide slurry was separated by solid solution of three-layer thicker and countercurrent washing, and the pregnant solution was clarified by frame clarifier and then sent to zinc powder for gold precipitation. The gold mud was dried and then sent to converter for smelting.The barren solution replacement and second section of the three layers thickener underflow vacuum filter in the filtrate in addition to the part of the return used lotion, the rest of the regenerative recovery of cyanide by sulfuric acid acidification process, with a sodium hydroxide solution absorbed available containing 20.35% sodium cyanide, containing 0.67% sodium hydroxide alkaline sodium cyanide solution, return to cyanide leaching operation, can save a large amount of sodium cyanide.
