Example of gold heap leaching field in northern Nevada
The heap leaching ore is open-pit mining with a scale of 2270t∕d, with an average grade of 1.16g∕t, and the stope is 1km away from the heap leaching field. The ore adopts two sections of closed-circuit crushing ore, the first section adopts jaw crusher , the second section adopts cone crusher , the ore size of the pile is -15mm, and the binder is No. 11 Dulantite cement, the dosage is 3.5～. 5.0kg∕t mine, the cement is added to the discharge belt after a crushing, so that a piece of broken ore is mixed with cement and joined into the cone crusher . The crushed ore and binder mixture are transported to the cantilevered heaper and the mixture is sprayed to the mixture at the discharge end of the heaper. The water content of the mixture is 9%. When the mixture slides down the cone, the mixture Then gather together to form a pellet. The pellets were transported to the asphalt mat with a front end loader for 2 days. The heap leaching site has a total of 5 yards, each with a mine capacity of 15,400 tons. The three mines are in different leaching stages, one is unloading and the other is being piled up. Five piles of mines are connected in sequence to carry out different stages of operation. The concentration of the sodium cyanide solution was 0.5 kg ∕m 3 , the spray intensity was 9.8 to 12.2 L h (h·m 2 ), and the pH was adjusted with caustic soda, and the leaching period was 20 d. The gold in the leachate is adsorbed by the carbon column, the gold-loaded carbon is desorbed with alkaline ethanol, and then electrowinned, the cathode is made of steel wool, and the steel wool is smelted with Dolkin ingot. The total recovery of heap leaching is 60%. The table below also lists some examples of simple comparisons between granulation and non-granulation leaching cycles and metal recovery. Readers can see the superiority of granulation heap leaching. Table Comparison of foreign granulation and non-granulation column leaching test results Mine name Ore nature Granulation Metal grade (g∕t) Adhesive addition amount (kg∕t mine) Agglomerate water content (%) Penetration velocity (L∕ h·m 2 ) Leaching cycle (d) Metal recovery rate (%) Au Ag cement lime Nevada Non- clay No granulation 3.10 0 - 0 0.383 5 90 Granulation 3.41 4.54 - 8 0.883 1.5 91 Yili Mine clay No granulation 6.51 0 - 0 0.021 9 91 Granulation 7.13 4.54 - 12 0.841 2 91 Idaho Off-balance sheet mine No granulation 1.86 0 - 0 0.0021 31 82 Granulation 1.86 4.54 - 10 0.176 5 92 Nevada Off-balance sheet mine No granulation 71.3 0 - 0 0.0042 30 74 Granulation 71.3 4.54 - 9 21.03 8 29 Tonopa Silver ore No granulation 43.4 0 - 0 0.0025 twenty three 64 Granulation 43.4 4.54 - 9 0.841 twenty three 92 Nevada Gold-containing tailings No granulation 1.24 0 0 0 0 - - Granulation 1.24 6.8 6.8 twenty two 15.14 7 86 California Gold-containing tailings No granulation 29.4 0 0 0 0 - - Granulation 29.4 6.8 6.8 18 18.1 11 74 Montana Gold-containing tailings No granulation 1.55 0 0 0 0.003 4 40 Granulation 1.55 9.0 9.0 twenty two 5.00 2 80 Southern Nevada Gold-containing tailings No granulation 3.72 0 0 0 0.0004 27 16 Granulation 4.03 4.5 4.5 16 21.448 3 80 Precision Annealed Seamless Steel Pipe Precision Annealed Seamless Steel Pipe,Annealed Stainless Tubing,Precision Annealed Seamless Steel Pipe Bollards,Precision Annealed Seamless Steel Pipe And Fittings Shandong Jianlong Steel Co. , https://www.jianlongsteelpipe.com