Gold mining (1) mining gold deposit type gold deposits are mainly divided into two categories: one for the gold deposit, mostly distributed in the mountain areas, the internal force of geological processes (mainly volcano, magmatism, metamorphism), also called the mountain of gold, gold in gold deposit; the other for the placer gold deposit, the gold out of the ground, through long-term weathering and denudation, broken gold grain, gold, gold at the end of the handling of the wind, water, and gathered in the sorting process of water flow and sediment in riverside, lakeside, coast and the formation of alluvial, pluvial or beach sand gold deposit. Some gold weathering and erosion, product of debris accumulation in the place, the formation of residual sand gold deposit; if along the slope, the slope is the formation of gold placer. The placer gold deposit, also known as the exogenous gold deposit, can be formed in the Paleozoic, Mesozoic, third, quaternary or modern times. In addition, there is an associated gold, its gold content is low, often in non-ferrous metal mines in the process of recycling and comprehensive utilization.

Ancient China already has a mountain of gold, gold. But the meaning of gold vein gold deposit, but also includes the eluvial and Deluvial gold deposit, which refers to the production of gold. The ancient placer gold deposit can be divided into "gold water" (from "water washing and sand" gold) and "the ground sinking" and placer mining. Sand gold, gold particles, and it is obviously different from most of the gold particles called Kuai Jin, known as "nugget". Nugget that is often considered to be a major event in the history of gold mining. "Heavenly Creations" hardware - said: "there was a middle head for thousands of pieces, called gold mother. "The vast majority of nugget found in alluvial gold, some produced in the near surface of the secondary enrichment zone.

(gravity method, placer gold placer gold ore dressing process) gravity method is based on the mineral density (usually called the proportion) between sorting mineral. The density of different mineral particles in the moving medium (water, air and heavy liquid) by hydrodynamic and mechanical force, resulting in appropriate loose stratification and separation conditions, so that the mineral particles of different density separation. The commonly used gravity equipment: vibrating screen, jig, cyclone, spiral chute, ore dressing, centrifugal concentrator. Gravity separation is the most ancient gold, one of the most common ways. In the alluvial gold, gold is usually a single natural gold form, size is generally greater than 16 tons / M 3, and the big density difference, so gravity is methods don't gold placer is the most important and the most effective and economical. But in gold, gravity separation is rarely used alone, not as part of a combined gold extraction process, is generally in the grinding and classification in the loop, jig and spiral chute and dressing table with the use of recycling, early cleavage coarse monomer gold, in order to facilitate the subsequent flotation and cyanide into the industry, and can be obtained gold concentrate qualified. This method has been widely used in the mining of small gold mines and local groups, such as the gold ore ditch in Inner Mongolia. Gravity separation is main equipment of gold chute, various forms of jig and table, centrifugal separator. In addition to conventional gravity separation equipment, according to the production characteristics of gold deposits in China, absorbing foreign advanced equipment in the digestive,, I developed the Ross belt chute, chute, jig, the centrifugal washing unit new separation equipment, in the gold production in order to achieve good results. Such as Shandong Yinan gold ore dressing plant in the field of grinding circuit set soft cladding (Mao Tan) chute, the gold recovery rate up to 70%. Soft cladding chute for flotation and gold tailings, in order to improve the recovery rate of gold. Amalgamation method according to the production method can be divided into internal and external gold amalgamation. In the common law and the separation of gold mine gold placer mineral with amalgamation; while in the gold mines, usually as part of a joint amalgamation process and flotation, gravity separation, and is mainly used for cyanide, collecting coarse monomer gold.

1) jigging gold (gold dressing method, placer gold beneficiation) jigging gold is a jig for gold process choose gold equipment. The jig is commonly used in many types of gravity separation equipment. At present our country gold with typical Wahl diaphragm jig

The working principle of typical Wahl diaphragm jig is: when the eccentric driving mechanism to drive the diaphragm reciprocating motion, the pulsating flow of vertical alternating jig interior in the water through the mesh generated by. The material is selected to the bed, and the formation of the ore and water. When the water flows upward, the particles are in a loose state, and at this time the particles with different sizes are deposited at different velocities. When the water flows down, the suction effect occurs, and the mineral particles with large density and small size enter the lower layer through the bed gap.

(2) tabling gold placer gold ore dressing method, placer gold ore dressing process) tabling gold is gold to table as main equipment. The table is for processing at the level of medium flow in the device, a bed surface and the transmission mechanism is composed of two parts, the bed surface is composed of a drive mechanism moves the vertical reciprocating motion. In the mineral table separation was gradually completed in the bed during the process of reciprocating motion. The main factors contributing to the movement of mineral particles, in addition to their own gravity, the main flow and bed differential motion. In the movement, the mineral particles are subjected to the stratification on the bed surface and the separation from the bed surface. The result of the two effect is that different ore particles are discharged from different intervals of the bed surface. The table according to the selected other ore granularity, can be divided into coarse sand bed (>0.5 mm), fine sand bed (0.5 ~ 0.074 mm) and sludge bed (0.074 ~ 0.037 mm) three.

(3) chute with gold placer gold placer gold ore dressing method, beneficiation process) chute gold is an old and is still used in gravity separation method. Chute is main equipment of gold chute. The chute is a slope of 3 degrees to 4 degrees (maximum of not more than 14 DEG to 16 DEG) (wooden or steel) narrow chute. Gold industry can be manufactured locally. The separation principle is: the pulp is fed from the slotted head chute, the flow force, particle gravity (or centrifugal force), the combined effect of mineral particles and the friction force between the bottom of the tank, the mineral particles of different density loose stratification and separation, high density to concentrate at the bottom of the groove, small density for tailings. Chute for intermittent operation, when the bottom of ore deposition to a certain height, stop feeding, cleaning concentrate. The chute consists of coarse sand and mud chute chute, the former is suitable for processing coarse material, which is suitable for processing fine materials. Coarse sluice trough bottom is provided with a shop and baffle. Coarse sluice is the main equipment of sand gold ore dressing, widely used in land and gold dredger. Large chute on land is generally 15 meters, gold mining ship is generally 4 to 6 meters.

4) gold method selected spiral concentrator (ore dressing method, placer gold placer gold ore dressing process) spiral concentrator gold is gold with spiral concentrator as the main equipment. The spiral concentrator is integrated by gravity, friction force, centrifugal force and flow, a chute beneficiation equipment make the particle according to the proportion, particle size and shape separation. Its characteristic is the groove in the vertical direction is bent into a spiral. The sorting process is: from the above into slurry chute, chute to flow down along the spiral line. In the process of flow, the mineral particles are stratified. At high particle density distribution in the spiral groove, the inner edge of the fine particle density distribution in the spiral groove. The heavy product after the delamination is discharged by the discharge port at the bottom of the inner groove, and the light product is discharged from the end of the spiral groove. The spiral concentrator has the advantages of simple structure, easy manufacture, no transmission, no need of power; drawback is the poor material selecting effect not more than 6 mm, 0.05 mm and with flat gangue. Widely used in the selection of gold placer.

5) choose gold cone concentrator: cone concentrator is based on a pinched sluice (also called fan chute) the principle evolved. Pinched sluice fan-shaped groove is about 1 meters long, to mine end width of 125 ~ 400 mm, discharging end width of 25 ~ 9 mm, inclined groove surface, below the left. Pulp by upper center to the income, the distribution cone distribution into different cone. Mineral particles in the separation cone flow in the process of density stratification, and finally cut off the mouth will be light, heavy product separation. Reichert cone concentrator abroad there is a widely used in placer gold in the primaries, which is several conical vertical overlap, a few selected don.

The placer gold ore dressing method, placer gold placer gold ore beneficiation technology：