The development direction of hydrometallurgy

The birth and development of metallurgical science and technology, has always been closely linked with large-scale production of metallurgical industry. At present, although the production volume of the metallurgical industry has gradually stabilized, it is still one of the most important basic industries. With the development of society, people have realized that the mineral resources endowed by nature are limited, and the metallurgical industry, which is one of the important pillar industries of the national economy, is an industry that consumes a lot of materials and energy, and is also one of the major sources of environmental pollution. It has become an object of great concern to people, so the rational development and utilization of these precious resources is an important task for metallurgical scientists.

The technological progress of the metallurgical industry in the 20th century is quite rapid, and the development of hydrometallurgy is particularly remarkable. Since the 1970s, the development of hydrometallurgy has entered a very active stage. The main reasons are summarized as follows:

(1) The requirements for environmental protection are more stringent. In particular, the low concentration of SO ₂ flue gas emitted during the smelting of non-ferrous metal sulfide ore is one of the main sources of environmental pollution, leading to serious acid rain hazard in the atmosphere, forcing people to pay more attention to the hydrometallurgical clean production process without air pollution. . For example, in the 1980s, Canada has two built direct pressure leaching of zinc sulfide concentrates of zinc hydrometallurgy plant is in existing conventional roasting - leaching zinc smelting plant pressurized leaching technology In the expansion, while the zinc sulfide ore is pressurized and leached, the by-product element sulfur product not only eliminates the pollution problem of SO ₂ flue gas, but also solves the problem of transportation and outlet of sulfuric acid.

(2) Development and utilization of low-grade ore resources. With the continuous exploitation of natural deposits, some mineral resources have been depleted, and the mining grade of useful minerals in some metal deposits has generally declined. Case copper ore, copper mineable grade copper in the early 20th century is 1% or more to the late 20th century has been reduced to 0.2% to 0.3% copper. Some low-grade resources that were difficult to use economically in the past, such as tailings, off-balance mines or abandoned slag, have been re-approached or used. For example, Australia has extracted gold from the abandoned gold tailings in the past and achieved economic benefits.

(3) Comprehensive utilization of secondary resources of complex ore. The separation, extraction and comprehensive recovery of valuable components in materials by hydrometallurgy are relatively high. For the development and utilization of complex mineral resources, it relies more on the new technology of hydrometallurgy. From the rational use of resources and energy conservation, it is also effective to recover valuable metals and their compounds from secondary resources by hydrometallurgical method. One of the ways.

(4) The intersection and mutual penetration between disciplines has promoted the continuous development of hydrometallurgy. For example, the application of modern biotechnology in metallurgy has developed a new bio-metallurgy technology. Since the 1960s, large-scale industry has been applied to the extraction of low-grade copper ore. The past 10 years, the microbial oxidation pretreatment new technology with arsenic refractory gold deposit has been successful, has nearly 10 factories put into operation around the world. Biometallurgical technology is likely to be further extended to other non-ferrous metals or rare discs in the extraction process, with good prospects for development.

During this period, the research work of hydrometallurgy was also very active. The total number of published hydrometallurgical literatures in metallurgical disciplines increased from the initial 10% year by year. In the famous American Journal of Metals (now renamed the Journal of the Minerals, Metals and Materials Society), an annual report on "hydrometallurgy" is published annually, summarizing the previous year. The literature and development trends of hydrometallurgy, the literature cited has risen from about 100 articles per year to more than 300 articles, which can also be seen in the field of hydrometallurgy. At the same time, the international magazine "Hydrometallurgy", which was published in 1975, has been published in the field of wet metallurgy, such as wet extraction, separation and engineering in aqueous or non-aqueous solutions. The number of publications and the quality and quality of the papers are constantly increasing. In addition, some more specialized journals on separation science and technology, such as Separation Science and Technology, in 1965, Separation and Purification Method, in 1972, Solvent Extraction and Solvent Extraction and Ion Exchange was published in 1983 by Solvent Extraction Research and Development. Many of the papers involved hydrometallurgical chemistry and separation processes.

At the same time, national academic conferences in the field of hydrometallurgy are also active. The first International Conference on Hydrometallurgy was held in 1963, and the meeting decided to organize it once every 10 years. The second, third and fourth sessions were held in the United States in 1973, 1983 and 1993, and the fifth in Canada in 2003. Due to the long interval of 10 years, some countries, such as the United Kingdom, Germany, Australia, China and India, have also held international wet metallurgy conferences. At the same time, the American Institute of Metals (TMS), the Canadian Metallurgical Society (CIM), the Australian Institute of Mining and Metallurgy (AIMM), the Japan Institute of Mining and Metallurgy (MMIJ), etc., have a special "hydrometallurgy" at their annual meeting. Chapter report. The large-scale International Solvent Extraction Conference (ISEC) is usually held every three years. The number of papers and the scale of the conferences are increasing year by year. Among them, the content of separation chemistry and separation process of metal extraction accounts for a large proportion. The International Conference on Chemical Reaction Engineering is held every two years. For example, at the eighth session in 1984, a special branch of "hydrometallurgy" was also established. In addition, other more professional academic conferences, such as the UK's ion exchange and membrane separation conference, the International Precious Metals Conference, and the International Hydrothermal Reaction Conference, all involve the chemical extraction and separation process of hydrometallurgy.

China's hydrometallurgical research began in the 1950s. The Institute of Process Engineering of the Chinese Academy of Sciences (formerly the Institute of Chemical Metallurgy) first established the Hydrometallurgical Research Laboratory in 1956 to create high-pressure hydrometallurgical research in China. At the same time, the Changchun Institute of Applied Chemistry of the Chinese Academy of Sciences and the Department of Chemistry of Peking University, in the extraction and separation of rare earth metals, the Shanghai Institute of Organic Chemistry, Chinese Academy of Sciences in the synthesis and application of organic extractants, the Qinghai Salt Lake Research Institute of the Chinese Academy of Sciences in Salt Lake Resources A lot of work has been done on development and utilization. Some research institutes affiliated to the national industrial sector, such as Beijing Research Institute of Mining and Metallurgy, Changsha Research Institute of Mining and Metallurgy, Beijing Nonferrous Metals Research Institute, Beijing Nonferrous Metals Design and Research Institute, Beijing Institute of Chemical Metallurgy, Ministry of Nuclear Industry, Guangzhou Nonferrous Metals The Institute, Zhengzhou Light Metal Research Institute, Kunming Precious Metal Research Institute and metallurgical research institutes in some provinces and cities have all done a lot of work in the wet extraction and comprehensive utilization of mineral resources in China. Domestic institutions of higher learning, such as Tsinghua University, Central South University, Kunming University of Science and Technology, Beijing University of Science and Technology, Northeastern University, East China University of Science and Technology, South China University of Technology, Sichuan University (formerly Chengdu University of Science and Technology), Xi'an University of Architecture and Technology (formerly Xi'an Metallurgical Building) The Department of Metallurgy, the Department of Chemical Engineering, and some comprehensive universities such as Peking University, Fudan University, Shandong University, Zhongshan University, and Liaoning University have successively carried out research related to hydrometallurgical extraction and separation. Application basis and development research work. In China, mainly a combination of important mineral resources development and utilization, as Jinchuan mine nickel, cobalt, copper, and platinum group metal or the like, the header ore rare earth and niobium, panzhihua ore of titanium, vanadium, chromium, He has a large number of research and development work, such as the separation and extraction of polymetallic complex mines such as Hunan Shizhuyuan Mine and Guangxi Dachang Mine, as well as the high-yield characteristic mineral resources (such as tungsten, molybdenum , niobium , rare earth, etc.) in China. It has made important contributions to the construction and development of China's non-ferrous metals and rare metals industries.

Regarding the preliminary work of research and development of hydrometallurgy in China, Academician Chen Jiaxuan of the Institute of Process Engineering of the Chinese Academy of Sciences made a topic entitled "Hydrometallurgy of China" at the Third International Conference on Hydrometallurgy held in the United States in 1983. (Hydrometallurgy in China)'s conference report, a more comprehensive review. Subsequently, four international wet metallurgy conferences were successfully held in China (the first in Beijing in 1988, the second in Changsha in 1992, the third in Kunming in 1998, and the fourth in Xi'an in 2004). The conference proceedings were published, and Chinese scholars conducted extensive academic exchanges with their foreign counterparts. In the past 10 years, the number of Chinese scholars attending international academic conferences related to hydrometallurgy has increased year by year, and the contact and academic exchanges between China and foreign counterparts have also been strengthened. At the same time, in the 1990s, some monographs on hydrometallurgy were published in China, and the achievements and progress in the field of hydrometallurgy were introduced. Generally speaking, China's research and development work in the field of hydrometallurgy is still mainly focused on application.

In the 21st century, the research and development of hydrometallurgy in China will continue to focus on the needs of the country, aiming at the rational development and comprehensive utilization of China's mineral resources, expanding the application fields, and establishing clean and pollution-free production processes for the national economic construction. Provide a greater contribution to all the necessary quality materials. At the same time, according to the characteristics of the development of the discipline itself, we must attach importance to the basic research of hydrometallurgy, improve the level of research work and innovation, and develop to a new height. China's vast hydrometallurgical workers still have a long way to go in this regard.

Intergrated Design Batch Waste Plastic Pyrolysis Plant