Operation of gold adsorption by activated carbon in heap lea
2020-08-13 09:53Introduction：As described above, various adsorption equipment, its operation methods have their own characteristics. In order to increase the adsorption rate of activated carbon, however whatever the equipment, it is necessary to ensure as much as poss
As described above, various adsorption equipment, its operation methods have their own characteristics. In order to increase the adsorption rate of activated carbon, however whatever the equipment, it is necessary to ensure as much as possible that the gold-cyanide complex ions in your solution have full contact with the activated carbon, and must adopt the method of multi-stage series and countercurrent adsorption. The way in which the solutation is fed to the adsorption equipment, whether it is supplied directly by the pump or first by the pump, and then the solutation is supplied by the potential differential pressure head between the high tank and the adsorption column, the solution must have an appropriate linear velocity of flow. The condition of having activated carbon in the equipment to form a fluidized bed. Before the activated carbon is put into use, it must be stirred in a small tank, grinding away the sharp and fragile edges, and then sifting. Only if the granularity meets the requirement it can be put into use. Because the fine powder carbon in the adsorption process, it will be with the adsorption of gold and silver, with the tailing solutation discharge, resulting in gold loss. In order to avoid blockage in the adsorption column, the pregnant solutation should be cleared in advance, and some slime and suspended matter should be removed. The adsorption tailing solutation can be directly discharged into the low level liquid storage tank and be used as leaching solution after adjusting the concentration and pH value of leaching agent.Technical conditions for gold adsorption by activated carbon:
1. In order to obtain gold bearing carbon with high gold content, the gold grade of the adsorbed solution should be kept above 1g/m3 at the normal leaching stage; and some gold should be recovered as much as possible at the later stage of leaching or washing stage.,The gold grade of the adsorbed solution can be reduced to more than 0.3g/t.
2. The selected activated carbon must have large adsorption capacity for gold and high mechanical strength (the strength measured by ball milling method is more than 70%). At present, coconut shell activated carbon is mostly used in foreign heap leaching plants, and apricot shell activated carbon is mostly used in our country. These two kinds of activated carbon have better properties. which can be recommended;
3. The size of activated carbon should be controlled in the range of 12~30 mesh.
4. In order to induce activated carbon to form fluidized bed in adsorption tank (column, tower), it is necessary to ensure that the flow rate of the pregnant solutation into the adsorption tank (column, tower) is sufficient, generally controlled at 450 ~ 600 liters / (m2. minutes)
