Introduction to Gold Mineral Processing-Refining Technology (3)

1. gold mine gold smelting place 70 years ago, gold production at a preliminary stage of development, except for a few mines began to use cyanide gold extraction process, the real estate gold mine will mainly resulting from the re-election of placer gold and natural yield 30% gold extraction process concentrate smelting and amalgamation smelting amalgam as raw material in situ, on real estate only total amount of gold, gold by 70% * SMELTERY recovered.
After 1970, the production of gold gradually developed, and the gold extraction process of cyanide was increasingly applied. The mines increased the amount of real estate. In 1985, the output of finished gold products accounted for 70% of the national gold production. Most of the mineral products are produced by in-situ cyanidation and smelting.
Most traditional mining situ smelting crucible melting method, due to the nature of the production process and the handling of different materials, the yield of crude gold gold are not the same, directly sell the bank is not high because gold or silver are not pricing and other reasons, there In order to improve the quality and economic benefits, the mine has adopted chemical separation and remelting or electrolysis to carry out gold and silver separation and refining. In 1984, the Jiaojia Gold Mine experimented with a new process of hydrometallurgy, which electrochlorinated cyanide gold mud to remove *metals (gold extraction by aqueous solution chlorination and ammonia extraction) to obtain gold-containing grades of 99.9% finished gold and silver. 99.9% of silver ingots, copper and lead in gold mud are also recovered at the same time (the tendency to be treated by wet treatment of gold mud). Zhaoyuan Gold Mine successfully developed a Φ1.5×1.8m converter smelting gold mud, which replaced the previous smelting, reduced costs and improved working conditions. This method is widely applied in mines such as Shandong Xincheng Gold Mine, and the effect is good.
Zhaoyuan Smelter is the first gold smelter to be researched, designed and constructed by China. It specializes in the treatment of polymetallic sulphide gold concentrates. It mainly extracts gold and recovers silver, copper, lead and sulfur. It is a comprehensive smelting. A new type of enterprise integrating chemical industry. The completion and commissioning of Zhaoyuan Smelter has filled a technical gap for China's gold production and smelting process, using a roasting-acid leaching-(salt leaching)-cyanide leaching process to solve the long-term mining, selection and smelting. Production contradiction, solved the long-distance outbound loss of gold concentrate (annual loss rate 2% to 3%), transportation pressure and comprehensive utilization.
The design of the production process of the plant absorbs the advanced experience at home and abroad. The vacuum belt filter is used as the washing and filtering equipment for the leaching residue. The axial flow cyanide leaching tank is used for three leaching, three solid-liquid separation and leaching slag washing. Advanced process.
2. Recycling of associated gold in non-ferrous smelters In the production of gold, the recovery of associated gold in polymetallic ores occupies a considerable position. Gold and copper, lead and other non-ferrous metals are selected into the concentrate. In copper and lead smelting, gold and silver are recovered. In order to increase production of gold, some non-ferrous smelters in the country have built precious metal comprehensive recycling workshops. By 1985, there were more than 20 in the country. Apart from Shenyang smelters, there are mainly Zhuzhou, Shanghai, Yunnan, Chongqing, Wuhan and Fuchunjiang. Such as smelting plants and Tianjin, Taiyuan electrolytic copper plant. Among them, the production of companion gold in the three major smelters of Shenye, Shangye and Zhuye accounts for more than 90% of the total output of the national associated gold, which is an important force in China's gold production. The recovery of associated gold in these enterprises is based on the fact that in the process of copper and lead smelting, gold and silver are concentrated in blister copper and crude lead. When electrolytically refining blister copper and crude lead, gold and silver are deposited in the electrolytic anode mud, so it is extracted from the anode mud. Gold and silver are the main ways to recover associated gold and silver.
The treatment process of copper anode mud has been developed rapidly. Through continuous reform and innovation, the traditional fire process is more mature and perfect. The semi-wet process and the whole process are successfully tested and put into production. To make China's smelting technology and equipment level have been greatly improved. Such as the improvement of the fire removal process, the comprehensive recovery of valuable elements, the improvement of the furnace body and the improvement of the vacuum system. There are also the transformation of electrolytic cells, the promotion and application of intermediate frequency furnaces, etc., which have gradually matured and improved the fire smelting process, and improved the technical and economic indicators. Because the fire smelting process has stable technical conditions, mature technology, high comprehensive utilization, strong adaptability to raw materials, large processing capacity, low cost and so on, it is still a smelting plant such as Shenye, Zhuye and Shangye. A universally applied method. Fuchunjiang Smelter, Wuhan Smelter and Chongqing Smelter have achieved remarkable results with the new wet process. Yunnan Smelter and Tianjin Electrolytic Copper Plant have achieved success and put into production through the joint process of metallurgy and smelting, and have also achieved significant economic benefits. The successful test and application of the sulfuric acid slag gold extraction process has also created a new way for China's gold production and full utilization of resources.
(VI) Heap leaching production process Among the gold resources in China, the low-grade oxidized ore accounts for a certain proportion. It is economically uneconomical to use the conventional cyanidation process to treat gold ore, and the heap leaching process still has economic benefits. . Further expanding the scale of heap leaching production in the future is one of the ways to increase China's gold production. In the late 1970s, China began research on the heap leaching production process of low-grade gold-bearing oxidized ore. After successful small-scale production in the Danshan Hushan gold mine in Liaoning, it was successively in Linghu, Yindongpo, Yunnan, Yunnan. Some mines in Mojiang, Chongli, Hebei, and Chifeng in Inner Mongolia have been promoted and applied, and have achieved satisfactory economic results, which has opened the way for the development and utilization of low-grade gold-bearing oxidized ore. Because the heap leaching gold extraction process is simple, the operation is easy, the investment is small, the benefit is good, and the horse is fast, so the heap leaching gold extraction process develops rapidly. In recent years, the State Council and the Gold Corporation have attached great importance to the development of heap leaching production processes. The scale and quantity of heap leaching have seen new growth, and production technology is constantly improving and improving. The application of granulation technology and activated carbon adsorption column and the development of gold-loaded carbon desorption electrodeposition treatment process have added new vitality to the popularization and application of heap leaching gold extraction process.
According to incomplete statistics, there are more than 30 heap leaching sites in 10 provinces and autonomous regions, namely Henan, Hebei, Yunnan, Inner Mongolia, Jilin, Liaoning, Gansu, Guangxi, Shanxi and Hubei provinces, etc. Field service work.
Through a small test, it must be pointed out that ore with a grade of more than 3g/t should not be heap leached, which is a waste of resources.

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