How to select gold from gold placer gold dredger？

In the placer gold ore, most of the placer gold metal minerals exist in free state or alloy form, which is easy to sort, but the content is not large. Generally, the gravity separation method is used to treat placer gold. For example, the gold pan is equipped with a chute, jigging, shaking table, etc. for enrichment, and the concentrate can be treated with amalgamation. The following is a detailed explanation of the gold dredger's treatment of placer gold and the role of different processes of the gold dredger.

A gold dredger is a sand dredger equipped with various gold panning equipment, and its digging depth can reach 15 meters below the water surface. The gold panning ship has multiple excavation buckets, each bucket has a capacity of 225 liters, and operates at a speed of 31 buckets per minute. Rough selection is carried out on the gold dredger. The material is poured from the bucket of the excavator into the main funnel, and fed into a rotating cylindrical washing screen with a diameter of 2.3 meters and a length of 11 meters. The diameter of the screen hole is 9.5-16 mm. The material larger than 9.5 mm is discarded as tailings, and the material under the screen is sent to the double-layer chute for separation, the tailings in the chute enter the jig machine for re-separation, the jigging tailings are discarded, and the jigging concentrate is the rougher concentrate. Send ashore selected.

The rough concentrate of the gold dredger contains crude platinum, some gold and a considerable amount of magnetite, chromite and ilmenite, etc., and is first separated by four 2.4-meter Wilfrey shaking tables, and the shaker concentrate is passed through Screening and magnetic separation to remove magnetic minerals, non-magnetic products are then subjected to wind beneficiation to remove lighter gangue to obtain the final platinum concentrate. The concentrate contains platinum group metals up to 90%.

Platinum group minerals are enriched in the gold concentrate during gravity separation. After the concentration ore is mixed with mercury, the tailings usually contain a lot of iridium-osmium ore. In order to recover this part of iridium, the tailings can be separated from iron and pyrite by passing the tailings through a shaker or a suede chute. The concentrate containing iridium-osmium ore is first treated with acid to remove residual iron and pyrite, and then beneficiated.

The role of different processes of the gold dredger:

1. Screening Gold mining ship placer gold ore screening is usually carried out with a drum screen with good screening effect and thorough screening. According to the difference in mud content and the situation of bonding into agglomerates, it can be selected in the drum screen screening process. Add water to promote disintegration and free the monomer gold, which is beneficial to the recovery of gravity separation.

Second, the alluvial gold material after gravity selection and screening can enter the gravity separation process. Since the gold content in alluvial gold ore is extremely low, energy-saving and environmentally friendly gravity separation equipment must be used as roughing equipment. The gravity separation of alluvial gold ore mainly uses Chutes, jigs and other equipment, chutes are mainly used for rough separation and enrichment of placer gold ore with extremely low gold content, the loss rate is high, and the operation is complicated, but its cost is very low, equipment investment is small, and investment in jigs is large , continuous production, simple operation, high recovery rate, mainly used for roughing and enriching placer gold ore. The gold content of the rough concentrate produced by the jig is also much higher than that produced by the chute.

3. Purification The placer gold crude concentrate obtained by gravity separation equipment still contains other metals and impurities. In order to further increase the gold content for smelting, the crude concentrate is generally purified by gravity separation or amalgamation. This purification process uses more purification equipment such as shaking tables and amalgamation cylinders. Shaking tables are common gravity separation equipment. Featured. The recovery rate of the amalgamation cylinder is high, but the operation of the equipment is slightly complicated, and it is mostly used for the purification of small gold mines.