The process of extracting mercury from a slurry containing natural gold and extracting it due to the formation of amalgam between gold and mercury is one of the gold extraction methods for gold ore. The amalgamation process essentially involves the wetting and amalgamation of mercury by gold. The wetting of gold by mercury is carried out in an aqueous medium. In order for the mercury to wet the gold well, the gold particles must be exposed as much as possible to the surface of the ore and the surface of the gold particles should be kept fresh. Silver, copper, and iron compounds debris, oil and so easy gold particles and mercury contaminated mercury bead surface wettability is deteriorated to gold. For example, if the mercury contains a small amount of gold, silver or trace amounts of ruthenium metal, it can improve the wettability of mercury to gold. After the mercury wets the surface of the gold particles, it diffuses into the interior and forms an amalgam or alloy. This process is called amalgamation. Mercury amalgamation can be divided into three types: external amalgamation, internal amalgamation and special amalgamation. (1) External amalgamation method: Mercury is mixed after grinding, and there is no structural connection between grinding equipment and amalgamation equipment. Generally, it is used to recover coarse gold particles in the slurry flowing out from the ball mill . The main equipment is amalgamation board. . (2) Internal amalgamation method: The amalgamation operation is carried out in the grinding equipment, that is, grinding and amalgamation simultaneously; this method is only suitable for the treatment of gold ore with little copper, lead and zinc content and no sulfide. The equipment includes a boring machine, a boring machine, a ball mill, a rod mill and a mercury mixing cylinder. (3) Special amalgamation method: the activated amalgamation method is mainly used to treat some gold-containing materials that are not easy to be mixed with mercury. The product of mercury amalgamation is a mercury paste whose main component is gold amalgam and contains excess mercury and other impurities. The amalgam is first washed with water to remove heavy sand, gangue and other impurities trapped therein. The washed mercury paste is then filtered to remove free mercury. Finally, the pressure-filtered mercury paste is placed in a distillation tank, and the air is heated at the bottom to a temperature of about 1073 K. The mercury paste in the tank is decomposed and vaporized by heat, and escapes from the top duct. The outside of the duct has a cooling water jacket, and the liquefied mercury liquid flows into the cooling water basin along the pipe. Condensed mercury is combined with the filtered mercury to return to the amalgamation operation. The gold is left in the tube in the form of sponge gold, and after being smelted and refined, a gold ingot is obtained. DUDU NEW ENERGY AUTOMOBILE COMPANY , https://www.duduelectriccar.com