Due to the different types of gold ores, thegold extraction methods from oreare different, mainly including the gravity separation method, flotation method, amalgamation method and cyanide leaching method, resin in the pulp method, carbon paste adsorption method and heap leaching method. For some types of gold ores, the combined gold extraction methods from ore are often used in the gold processing plant.
There are many gold extraction methods from ore used in the production. The following are often used in the gold processing plant:
1. Gravity separation-cyanide leaching method
This gold extraction method from ore is suitable for treating quartz vein gold-bearing oxidized ore. The raw ore is processed by thegravity separation method, and the concentrate obtained by the gravity separation method is directly smelted. The middlings and tailings obtained by the gravity separation method are sent to cyanide leaching.
2. All-slime cyanidation method
Gold is produced from the quartz vein ore in fine or fine dispersion state. The gold ore has deep oxidation degree and does not contain Cu, As, Sb, Bi and carbon. This kind of ore is most suitable for the all-slime cyanidation CIP method.
CIP processis one of the main gold extraction methods from ore, which has the advantages of high recovery rate, strong adaptability to ores and it has the ability to extract gold locally.
CIP process mainly consists of four steps: leaching of gold-bearing ore in cyanidation solution, adsorption of activated carbon,desorption electrolysisof gold-bearing carbon and smelting of gold sludge. Since the cyanide used in this gold extraction methods from ore is highly toxic and easy to pollute the environment, it is suggested to adopt eco-friendly gold leaching reagent in the practice, which is low-toxicity, environmental-friendly and without changing the original cyanide equipment and process.
3. Gravity separation-flotation method
This gold extraction methods from ore recover the coarse gold by the gravity separation method, and the tailings are processed by the flotation method. This gold extraction methods from ore are applicable to the treatment of gold-bearing oxidized ores and the ores associated with free gold. It has a higher recovery rate than a singleflotationmethod.
4. Flotation-cyanide leaching method
This gold extraction methods from ore mainly have two schemes:
(1) Flotation-concentrate cyanide leaching method. It is suitable for the treatment of gold-bearing quartz vein ore and quartz pyrite ore which have a close symbiotic relationship with gold and sulfide.
(2) Flotation-roasting-cyanide process. This process is suitable for the treatment of floatable minerals containing harmful cyanidation.
5. Single flotation method
This gold extraction methods from ore is suitable for the treatment of fine gold particles, sulfide ore containing gold quartz vein with high floatability, polymetallic gold sulfide ore containing carbon (graphite) ore, etc.
6. Flotation-gravity separation method
This gold extraction method from ore is mainly based on flotation, which is suitable for the ore has a close symbiotic relationship with gold and sulfide, and the ore can only be recovered by smelting method. It is also suitable for gold-bearing quartz vein ore with uneven disseminated grain size, and has a higher recovery than a single flotation method.
7. Heap leaching method
Theheap leaching methodis a type of cyanide leaching method, which is suitable for treating ores with low-grade gold. This gold extraction method from ore has the advantages of a simple process, less investment and low cost.
8. Single amalgamation method
This gold extraction methods from ore is suitable for treating primary quartz vein deposits and oxidized ores containing coarse gold. Gold extraction by amalgamation method is an ancient and popular gold extraction methods from ore. It has been proved that adopting the amalgamation method in the gold extraction methods from ore can recover a part of gold grains in advance, and obviously reduce the loss of coarse gold grains in tailings.
The above eight gold extraction methods from ore are applied according to the various internal structures, ore types, and ore properties.
