1, Original ore roasting
The gold ore suitable for treatment by primary roasting method, its nature and characteristics are mainly reflected in the following aspects.
- gold carrier minerals such as pyrite, arsenopyrite, etc. embedded in fine particle size, to leaching and scattered distribution in the ore, and most of the gold and endowed in fine-grained pyrite, arsenopyrite, and other sulfide minerals, so mechanical grinding is difficult to make its exposure dissociation.
- A small part of gold and vein minerals’ close relationship, is a poor allied or carbonate, silicate minerals package.
- Ore contains “rob gold” material organic carbon and other harmful elements.
2, gold concentrate roasting
The vast majority of difficult to deal with the gold in the ore and sulfide symbiosis close relationship, the use of flotation can make the gold-bearing sulfide to get full and effective enrichment, the output of gold concentrate, and can obtain a high flotation recovery. Due to the complex composition of flotation gold concentrate, and the content of beneficial and harmful elements are high, direct cyanide leaching, gold leaching rate is low.
3, Hot pressing oxidation process
The hot pressing oxidation method is divided into acidic hot pressing oxidation and alkaline hot pressing oxidation.
Alkaline hot-press oxidation is applicable to the gold-bearing difficult-to-treat ores with high carbonate content.
Acidic hot-press oxidation is applicable to the treatment of hard-to-leach gold concentrates containing sulfur and arsenic.
Therefore, the acidic hot-pressing oxidation process is more widely used.
4, Joint pretreatment process
For the complex composition, many kinds of interfering elements, high content of typical difficult to treat gold concentrates, the use of a single pretreatment process is difficult to get the best results.
5, Amalgamation flotation
Suitable for processing natural gold embedded in coarse particle size, stored in pyrite and other sulfide ores. Different from single flotation is to add mercury plate for gold recovery after grinding, the recovery rate can reach 30-45%. After mercury amalgamation, the slurry is flotation through the overflow of the classifier. In order to make a better generation of mercury gold, grinding with a certain concentration of carbonic acid, caustic soda, etc., can make the mercury-gold recovery rate of 70%.
6, Gravity beneficiation
The use of gold and other minerals than the difference in flotation. The larger the difference in specific gravity, the easier to separate. The gold-bearing sands are placed into the cylinder sieve and flowed through the high-pressure water, and the gravel sands larger than the sieve holes are transported into the tailing field through the chute and belt; the sands smaller than the sieve holes are fed into the 1-3 section circular jigger through the public orchestrator, and the concentrate flows into the shaker through the 3 section jigger for coarse, fine and sweeping selection to produce the fine sand ore.