Re-election is one of the earliest methods of mineral processing . A long time ago ancient people began to use the re-election method, natural sand gold panning in the river with what hides. The jig was introduced as early as the 14th-15th centuries. Until now, the main features of the re-election equipment have been retained. After the industrial revolution in the 18th century. With the development of production, the re-election technology is also becoming more and more perfect. In the 1930s and 1940s, a mechanical piston jig appeared in Germany. In 1893, the first air-moving pistonless jig was invented - the famous Baum-type jig. Invented the modern type in the late 19th century. Mechanical shaker. Until the early 20th century, the flotation method was widely used, the re-election method has been the main method of mineral processing. The most efficient re-election method - heavy medium beneficiation. It was used in industry in 1858. At that time only in selected coal waves calcium chloride solution, due to the large loss solution, so it does not get promoted. In 1917, the water sand suspension coal preparation method appeared again. In 1926, Soviet engineer EA Slepnov proposed a heavy medium beneficiation method using a stable suspension. Since then, heavy medium mineral processing has been widely used. Due to the advantages of high sorting efficiency, large processing capacity and suitable for processing difficult minerals, heavy medium beneficiation has been rapidly developed in many countries. The theoretical research work of re-election began after the mechanization of re-election equipment. From the point of view of fluid mechanics, the squared formula of the resistance of the sphere proposed by Newton in the early 18th century. In 1851, the British physicist GG Stokes developed the drilling resistance formula. For the early re-election theory research work. Provide a theoretical basis. The initial theoretical research work began by studying the laws of motion of individual schools in the medium. These findings and findings were found to be inconsistent with actual production. Because of the re-election process, it is not the movement of individual particles in the medium, but the movement of the particles in the medium. Only then began to study the interference and sedimentation law of the ore group in the medium. In this respect, the former Soviet scholar nB Lishenke did extensive research work. It was proposed that the jigging is a stratification of the relative density of suspended matter in the ascending water flow, and in 1936 it was the first in the world. This re-election textbook. Later, in 1947, the German EW Maier proposed the theoretical model of jigging energy from the perspective of bed energy drop. The jigging process was explained. In 1959, the Soviet HH Vinogradov proposed the "probability-statistical model" which has been widely recognized in recent years. It regards the jigging process as a group motion of various physical nature of the school movement, which has a probabilistic nature. Because the re-election process itself has a lot of factors. Until now, the theoretical research on jigging and other re-election processes. Different schools still hold different views. In the future, we should concentrate on finding a way to unify various theories. The approach will ultimately solve the problem of re-election equipment and process parameters objectively. Since the emergence of hydrocyclones in the Netherlands in the 1940s, a major step has been taken to strengthen the sorting process with rotary flow. It is widely used in the classification and sorting process of fine minerals. Although its theoretical research is still immature, it is one of the main directions of current re-election development. With the development of modern science and technology, tracer has now begun to be used. The atomic and modern testing techniques directly observe the movement of the granulation and study the movement law of the ore during the re-election process. In order to meet the needs of production automation and equipment large-scale, Based on the mathematical statistics method, the research on the ship law of the beneficiation process is summarized, and the mathematical model between the process parameters and the equipment parameters is compiled. It provides a basis for the automatic control side and equipment design of the process production. In recent years, due to the improvement of mining mechanization. More and more poor ore and fine-grained ore are being developed and utilized, and re-election is faced with the task of improving equipment handling capacity and strengthening the recovery of fine-grained grades. The equipment side is being enlarged, centrifuged and enlarged. The direction of stratification has developed. The transmission mode has also adopted a variety of compound movements. In this respect, China has achieved a lot and has to achieve. The history and achievements of re-election technology in China There has been a long history of re-election in China. Smelting steel began about 4,000 years ago. The Simu Ding, unearthed from Yincheng, weighed 1400 pounds, which is a superb metallurgical technology. In the Warring States Period (403-221 BC), the application of iron was promoted. In order to provide raw materials for metallurgical production, mining and mineral processing technologies are also quite developed. In the Ming Dynasty. China's mining, metallurgy and metal processing industry. Whether in production scale, production, or technical aspects, they are at the forefront of the world. In 1637, the famous scientist of the Ming Dynasty Song Yingxing's "Heavenly Creations" summed up the industrial and agricultural production of the working people of the past generations. In the history of our country, the first systematic discussion of mining engineering and washing ore was carried out. Etc. There are many examples of application reselection sorting. For example, windmills are used to sort cereals, and hydrological classification methods are used to extract Nishang. Washing iron sand and tin sand ore. These accounts reflect the development of China's occupation and selection of technology. China's re-election industry has been lagging behind in old China. Equipment is outdated. Poor management. Production is extremely abnormal. After the founding of New China, the production of mineral raw materials has been placed in a priority position. Several large and medium-sized re-election plants and coal preparation plants have been established in China's important tungsten, tin and coal bases. With the establishment of China's cutting-edge technology industry, a number of re-election plants for processing rare metal ore have also been built. During the 1960s, the re-election method was used to treat the ore-like hematite ore, and a heavy medium ore dressing plant was established in the lead and zinc non-ferrous metal concentrator. The heavy medium coal preparation plant was also developed. At the same time, China's ancient gold-removing industry was transformed with modern re-election technology. A number of floating gold mining vessels were established on the long river banks in Jilin and Heilongjiang provinces. Due to the characteristics of China's energy resources, coal is increasingly becoming the main source of energy. China has abundant coal resources and complete coal types. With the growth of the coal industry, the selection of coal has also been rapidly developed. In addition, the re-election method has also been widely used in the chemical and building materials sectors. After the reform and opening up, China's national economy has developed rapidly, and the re-election technology has been further developed. Many new technologies, new processes and new equipment have emerged. In the 21st century, China's economic construction achievements have become more remarkable. It has become a major manufacturing country in the world. At present, China's tungsten, tin ore re-election technology has taken the lead in the world. The processing capacity of raw ore is nearly 100 times higher than that before liberation, and more than ten kinds of associated metal elements such as iron, copper , lead, zinc, tungsten, secret, antimony , titanium and cobalt have been comprehensively recovered. The output of tungsten concentrate has reached the top in the world and has become an important exporter of tungsten sand in the world. Significant achievements have also been made in the research of new technologies and new equipment. The re-election method has been successfully applied in the treatment of difficult vanadium- titanium magnetite ore. Looking for a country to use the principle of unsteady flow on the film casting, made a vibrating belt with a composite movement. A large number of new re-election equipments such as rotary spiders, tooth-wave jigs, turntable concentrators, and continuous operation centrifugal concentrators have been successfully developed and successfully applied. The new process of heavy medium coal preparation has been promoted, and the inclined wheel and vertical wheel tributary sorting machine, three-product heavy medium cyclone, electromagnetic air damper screen air chamber jig and so on have been successfully developed. In order to realize China's strategic goal of achieving a well-off society in the middle of this century, we still need to have greater development and face arduous tasks. The mineral raw materials processing industry faces unprecedented opportunities for construction. The rapid development of the economy. The demand for raw materials is growing, and the mineral raw materials processing industry faces unprecedented opportunities and challenges. Re-election of production technology is bound to achieve greater development. From the current situation, China's mineral processing industry still has many problems such as uneven development, imperfect comprehensive utilization and low level of automation. Therefore, we must step up our efforts, study hard, and extensively absorb advanced international technology in order to advance the science and technology of China's mineral processing industry to a new level as soon as possible. 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