The second example of all-slime cyanide carbon in pulp proce
2020-09-18 09:51Introduction：The secondexample of all-slime cyanidecarbon in pulp process-The Holmstack Gold beneficationplant, USA In 1973, Holmstack Gold beneficationplant stopped using mercury mixed process to extract gold and switched to carbon in pulp processto e
The second example of all-slime cyanide carbon in pulp process- The Holmstack Gold benefication plant, USA
In 1973, Holmstack Gold benefication plant stopped using mercury mixed process to extract gold and switched to carbon in pulp process to extract gold. After crushing and grinding, the raw ore was leached by agitation cyanide. After cyanide leaching, the slurry was removed from sawdust and coarse ore by a vibrating screen with 0.701 mm sieve, and then sent to the adsorption loop by an air hoist.
The adsorption process is usually composed of four air agitation tanks in series, each of which is equipped with a vibrating screen. The regenerated activated carbon and new carbon are added to the last adsorption tank, and the saturated gold loaded carbon is sifted out from the first adsorption tank. Wash and send to desorption process. During operation, the propeller was removed to the vibrating sieve, and the slurry flowed into the next adsorption tank, and the carbon particles on the screen entered the adsorption tank, thus realizing the reverse flow of the slurry and activated carbon particles. The vibrating screen was worn seriously to the activated carbon, and then the fixed slot screen was used.
The saturated gold loaded carbon was desorbed in a conical stainless steel desorption tank. The hot (88 ℃) alkali solution of 1%NaOH+ 0.2%NaCN was used for desorption. Hot lye flows from top to bottom through two desorption tanks in series, resulting in gold desorption solution (liquid) transmission product. If the gold content in the activated carbon is 9000 g / t, the gold content in activated carbon can be reduced to 150g / ton after 50 hours desorption, and the desorption rate can reach 98g/ton. The desorption solution was fed into three FRP electrolytes in series for electrodeposition of gold. Anodic solution is sodium hydroxide solution, desorption solution into the cathode chamber. Each room solution circulates alone. After the first cathode chamber passes through the second and the third cathode cell, the waste liquid is almost free of gold, and the electrowinning waste liquid is returned for desorption to reduce the consumption of cyanide. The recovery of gold is greater than 90%.
