At present, according to the complexity of ore composition and the difficulty of mineral processing, gold ore can be roughly divided into lean sulfide ore, high sulfide gold ore, polymetallic sulfide gold ore, gold copper ore, telluride gold ore and gold-bearing oxide ores. Different types of gold ores have different mineral processing methods due to their different properties.
The mineral processing method of six kinds of gold ore
Next, I will take you to understand the ore characteristics of various types of gold ore and the commonly used mineral processing methods.
Sulphide-lean gold ore and its mineral processing method
The material composition of this kind of ore is relatively simple, and most of them are quartz vein type or hydrothermal alteration type. Pyrite is the main sulfide but its content is small, and it is occasionally accompanied by minerals such as copper, lead, zinc, tungsten, aluminum, etc. Gold minerals are mainly natural gold, and other minerals have no recovery value or can only be recovered as by-products.
Sulphide-poor ores can be sorted by relatively simple gold ore mineral processing methods. For example, coarse-grained gold is recovered by gravity separation, fine-grained gold is generally recovered by flotation, and the flotation concentrate is then treated by cyanidation. The lean ore is recovered by the full mud cyanidation method.
High sulfide gold ore and its mineral processing method
This type of ore contains a lot of pyrite or arsenopyrite, and they are also recycled objects like gold. The grade of gold is on the low side with little change, and the natural gold particles are relatively small and mostly wrapped in pyrite. It is generally relatively simple to separate gold and sulfides by flotation; but to separate gold and sulfides requires a simple combined process of separation and smelting, otherwise the recovery index of gold is not high.
Polymetallic sulfide gold ore and its mineral processing method
This type of ore is characterized by high sulfide content. Besides gold, the ore also contains copper, lead, zinc, silver, tungsten, antimony and other metal minerals, and the latter often has the value of separate mining and recovery. The variation range of gold particle size is large, and the distribution in the ore is particularly uneven. In addition to being closely related to pyrite, natural gold is also closely symbiotic with copper, lead, zinc, silver, tungsten, antimony and other minerals. Metal minerals that need to be comprehensively recovered diverse.
For the selection of this type of gold-bearing ore, it is necessary to first determine its ore type, and then determine the specific mineral processing method according to the difference between its metal minerals and gangue minerals. For example, for gold-bearing copper-iron ore, the main metal minerals are chalcopyrite and magnetite, and natural gold occurs in chalcopyrite in the form of fine particles, which can be separated by flotation-magnetic separation combined mineral processing. Separately, two products such as gold-bearing copper concentrate and iron concentrate are obtained respectively.
Gold-bearing copper ore and its mineral processing method
The difference between this type of ore and the gold-bearing copper sulfide ore in the polymetallic sulfide gold-bearing ore is that the grade of gold is lower, but gold is the main comprehensive recovery element. The particle size of gold minerals is medium, and the symbiosis relationship with copper minerals is complicated. Flotation + flotation concentrate fire treatment can be used for separation, that is, the copper-gold concentrate is first obtained by flotation, and then the copper-gold concentrate obtained by flotation is separated. The ore is sent to the smelter for smelting, and gold is recovered during the smelting process.
Telluride-containing gold ore and its mineral processing method
Gold-bearing minerals are still dominated by natural gold, but a considerable part of gold occurs in gold telluride. From the perspective of origin, these ores are mostly low-temperature hydrothermal deposits, and the gangue minerals mainly include quartz, chalcedony quartz and carbonate minerals.
Such gold-bearing ores are often recovered by flotation. Due to the brittleness of gold telluride minerals, it is easy to muddy during the grinding process, which brings difficulties to the flotation of gold telluride minerals. Therefore, when dealing with gold telluride ores, the process of stage grinding and stage flotation is often used.
Gold-bearing oxidized ore and its mineral processing method
The main metal mineral of this kind of mineral is limonite, which contains no or little sulfide, but contains stable secondary minerals such as gold-containing iron hydroxide or iron hydrous oxide and some quartz, which is the mineral composition of this type of ore main features of . Most of the gold occurs in the main gangue minerals and weathered metal oxide fissures. The particle size of gold varies greatly, and the mineral composition is relatively simple. The separation methods are mainly gravity separation and cyanidation.
For partially oxidized ores, gravity separation + cyanidation method is often used for separation. For all oxidized ores, coarse-grained gold is recovered by gravity separation, ore slime is separated by stirring cyanide, and ore sand is separated by percolation cyanide.
In summary
Gold ore resources are very precious. In order to select ores more reasonably, gold ore mineral processing methods are very important.
If you want to extract gold from gold ore in a more economical and environmentally friendly way, you should first conduct a mineral processing test, comprehensively analyze the properties of the ore, and obtain a scientific mineral processing test report to determine which gold ore mineral processing method to use. Determine the mineral processing plan after considering the actual situation of the mineral processing plant, investment and other factors in order to achieve the ideal return on investment.