The development of mineral processing engineering is closely related to the need for human beings to expand the quality and quantity of mineral resources in nature. The mineral processing process itself has a long history of development. Manual picking was carried out very early. After the 19th century, mechanical beneficiation equipment appeared in foreign countries. The application of froth flotation in the 1920s and the emergence of various flotation reagents and equipment greatly promoted the development of beneficiation technology and promoted it. Development and utilization of refractory, composite or fine-grained minerals. The development and needs of production have promoted human in-depth research on the theory of mineral processing.
First, the task of the beneficiation project
The development of mineral processing projects may develop and utilize mineral resources that are “poor, crystallized, and miscellaneous†in nature, and provide economically rational and technically feasible primary raw materials or products for further processing. From this, we can see the important strategic position of the mineral processing discipline in the development of the national economy, and determine its specific tasks:
(1) Increasing the grade of useful minerals and expanding the scope of utilization of mineral resources. According to the survey, China has more lean ore and less rich ore, and many of the poor ore resources need to be processed before being used as the next industrial raw material. Such as iron ore ferrous metals in the grade of greater than 50% accounted for only 23% of the country's total iron ore beneficiation process after the rest has to be manufactured **** bonanza to work as an iron raw material.
(Ii) improve product quality: non-metallic mineral kaolin, bentonite, zeolite, fluorite, silica dust, kieselguhr, sericite and so need to remove the iron, titanium and other impurities and improve the whiteness; coal washing need to reduce Qualified metallurgical coke can be produced by ash and sulfur and phosphorus content.
(III) Comprehensive utilization of symbiotic and companion generation points: Non-ferrous metal ores are often produced together. Because they are not compatible with each other, they need to be separated by mineral processing to be used as raw materials for smelting. (IV) Development and utilization of secondary resources: secondary resources including old metals and other solid wastes, wastewater and “exhaust gas†treatment and utilization, rely heavily on mineral processing technology, the most characteristic of natural minerals is limited quantity and development One time, so "recycling of resources" is the biggest savings.
(5) Utilization of marine resources. Salts marine resources including tuberculosis and the ocean floor manganese dissolved in seawater. There are 36 kinds of elements in seawater. In addition to extracting NaCl, KCl, MgCl2, Na2SO4, MgCO3, B, I, and Li, it can also extract energy materials such as U, Th, and thorium.
Second, the strategic position of mineral processing in the development of national economy
Mineral resources are the basis for human survival and social development. In today's world, 80% of industrial raw materials and 95% of energy are taken from mineral resources. With the continuous development of the economies of various countries, the society has more and more demand for mineral products. On the one hand, it promotes the progress of mineral processing engineering technology, on the other hand, it pollutes the environment in which human beings live. How to coordinate the development of mineral resources development and environmental protection is a common problem facing all countries in the world. The depth and breadth of natural resource development and utilization depend on the development of science and technology, and the development of mineral processing technology plays a key role. For example, every cubic kilometer of rock contains 3 million tons of Al2, 3 million tons of Fe, 260,000 tons of Cu, 10,000 tons of Sn, 100,000 tons of Au, and 10 million tons of U. If high technology separates it, then we can use it on the earth. The resources are very broad, which will greatly promote the development of social economy.
Third, the status quo and development trend abroad
(1) Foreign status
In the late 50s and 70s of the last century, the ore dressing industry had a great development abroad, mainly in the following aspects: 1. The large-scale selection of plants. 2. The equipment is large. 3. Research and application of new mineral processing technology and science and technology. Among the most representative major developments are “dry and wet self-grinding techniques†to simplify the ore crushing process; “joint processes†for difficult to separate difficult minerals, including “selection, metallurgy, mineral processing – biometallurgy†A new approach to the treatment of fine-grained minerals by a combined approach. 4. Development of new high-efficiency equipment. 5. The development of academic institutions. Well-known universities in many countries offer courses in mineral processing engineering, and the state-advanced countries have established mineral processing or granulation associations and special magazines.
The development of the mineral processing industry also raised some urgent problems to be solved: 1. The expansion of the size of the ore dressing plant and the large-scale equipment, which brought new problems to the manufacturing and production operation management of the equipment, requiring higher mechanization and automation levels. Otherwise, the simple equipment size will not bring better economic benefits. 2. New processes and new equipments have many new problems to be solved in practice. For example, flocculation flotation requires not only new chemicals, but also fine grinding of ores, and there are still some difficulties in industrial applications. 3. The original analog amplification algorithm is not suitable for large-scale and new equipment. 4. The increasing mineral resources of complex symbiosis, low-grade and micro-embedded, and the large-scale development and utilization of many non-metallic mineral resources have brought many new problems to be solved.
(II) Trends in future development
Looking at the future development trend from the development dynamics since the 1980s:
1. Breaking the boundaries of traditional mineral processing projects in terms of depth and breadth. The original beneficiation project mainly refers to the deep processing of natural mineral resources, and the ore dressing technology is now expanded to be applied to the treatment of “three wastesâ€, environmental protection, seawater dissolved matter and development and utilization of marine manganese nodules. With the development of industry, the demand for raw materials is expanding, so expanding the application field of mineral processing is an objective and inevitable development trend. Therefore, the future beneficiation is no longer limited to the processing after mining, but should also be developed into the local application of the deposit, including the regeneration of waste; the beneficiation will extend to the next step with a strong force, with pyrometallurgy, wet method Metallurgical combination, while expanding the application of mineral processing, improve the level and efficiency of the beneficiation itself, while minimizing the pollution to the environment, this is the general trend of mineral processing development.
2. Make full use of mineral resources and conduct research on “no tail process†or “no waste processâ€. While trying to increase the recovery rate of useful ingredients in foreign countries, we attach great importance to the comprehensive utilization of resources. Generally, the comprehensive utilization rate of non-ferrous metals is over 80%~90%. The current trend is to conduct research on “tailless processes†or “no waste processesâ€.
3. Development and utilization of new technologies and new processes. The "multi-force field" combined action equipment, a multi-agent "synergy" process. Research and development of "comprehensive mineral processing technology" with multiple principles "joint effect".
4. Energy conservation research. 40% to 80% of the energy consumption in mineral processing projects is consumed by the ore grinding operation. According to statistics, the annual consumption of energy consumed in ore crushing operations in the world accounts for about 3% to 4% of the world's total power generation; therefore, the energy consumption of crushing operations is a research field that is highly valued abroad. Now based on the new theory of crushing, to develop new and efficient crushing technology.
5. Research on corrosion mechanism and wear resistant materials. Due to mechanical wear and chemical corrosion, the ore dressing process consumes a large amount of metal materials. For this reason, two studies have been carried out abroad, one is the study of corrosion mechanism. Sodium nitrite, sodium metasilicate, or chromium as a preservative, can reduce the amount of chemical etching 49.7%, respectively, 45.7%, 45.9%. In the 1980s, a "magnetic liner" was tested in the United States, Sweden, and Norway, which greatly extended the service life.
6, the development of special functions, high efficiency agents. For example U.S. Doyle production of Zn, Co, Cu, Ni sulfide and Pt, Pd and other strong weak performance collector lead of the other mineral collector agents capacity; copper sulfide while strong COLLECTING Other minerals with weak mineral harvesting capacity; Italian research.
7. The application of high technology in mineral processing. The superconducting magnetic separator has reached the application stage. The American Eliz Magnetic Company has produced a superconducting magnetic separator with a diameter of 3.05m. Superconducting magnets are a major breakthrough in beneficiation technology. The current research and development is to improve superconducting systems, increase production, reduce costs, and expand applications. The use of microwave radiation can contribute to selective rupture and selective separation of minerals. Microwave radiation has two effects. The first is to raise the temperature of the mineral. The magnitude of the temperature rise depends on the nature of each ore, which helps to selectively rupture along the mineral interface. Second, because each mineral absorbs microwave radiation. The energy is different, which increases the difference in mineral properties. For example, pyrite may form a magnetic phase on the surface after microwave irradiation, so that it can be separated by magnetic separation.
8. Biometallurgy. Biometallurgy has a wide range of applications, low cost and no pollution to the environment, so it has a broad development prospect. At present, the same height as conventional beneficiation methods has been mentioned in the field of mineral processing engineering.
9. Simulation and optimization of mineral engineering Due to the diversity of the nature of mineral resources, the complexity of the production process, and the randomness of the process conditions, so far, the preparation of mineral processing methods and processes, the selection of equipment, and the design of the concentrator I have to rely mainly on experiments to solve. To this end, foreign countries have paid special attention to the mathematical modeling and simulation of mineral engineering in recent years. At present, the optimization design and optimization operation of the concentrator cannot be carried out, and only the auxiliary design can be carried out.
10. Automation. It is difficult for the ore dressing plant to maintain the optimal state of production by manual operation. Therefore, foreign countries attach great importance to the automation control problem of the concentrator. Generally speaking, it lags behind other departments such as metallurgy and chemical industry. The automation of the concentrator is subject to the mathematical model of the ore dressing, the control of the instrument and the computer. Since the 1980s, due to the further development of mathematical models, especially the emergence of new and advanced control instruments, the automatic control level of the concentrator has been further advanced. The future development trend is to combine the “expert control system†with the optimal timely control to adjust the production parameters according to the nature of the ore, so that the ore dressing production remains optimal.
4. Overview of China's mineral resources and market demand
(1) Overview of China's mineral resources
China is one of the few countries in the world with a complete range of mineral resources and abundant reserves. Before the founding of New China, China's mineral resources processing industry was very weak, and there were only a few factories that used mineralized equipment to process mineral products. In 1949, China's annual output of steel was 150,000 tons, coal was 32 million tons, non-ferrous metals were 13,000 tons, pyrites were 10,000 tons, and phosphorus was less than 100,000 tons. The total output value of the country's mining industry was less than 1.8 billion yuan. At that time, China's mining industry was almost in a state of self-made, and it was a small mining country. Since the founding of New China, especially since the Third Plenary Session of the Eleventh Central Committee of the Party and since the reform and opening up, the state has attached great importance to the development and utilization of mineral resources. By 1998, China had built 10,879 state-owned large and medium-sized mines and 27,854 townships and collective enterprises; more than 300 cities have been supported by mines; more than 150 kinds of minerals have been developed and utilized, and the exploitation and utilization of mineral resources More than 14 million people. In 1998, the three major mineral resources of steel, coal and cement ranked first in the world; non-ferrous metals and gold production ranked second and fifth respectively; from now until now, China's total output of non-ferrous metals jumped Ranked first in the world. The total output value of the country's mining industry exceeds 400 billion yuan, and the output value of the mining-related energy and raw materials industry exceeds 2 trillion yuan. China has become the world's second largest mining country after the United States. A special agent for zinc oxide ; a filter aid for increasing the filtration effect; and a grinding aid for increasing the grinding effect. The rapid development of mining raw materials processing has provided a strong material foundation for China's national economic construction. However, compared with developed countries, mineral raw material processing technology still has a gap, resulting in excessive consumption of mineral resources. Since the founding of the People's Republic of China, China's GDP has increased by more than 10 times, while the consumption of mineral resources has increased by more than 40 times. At the turn of the century, where the contradiction between population, resources and environment has become increasingly prominent, we have carefully analyzed the status of China's mineral resources and reviewed minerals. The achievements in the field of processing engineering technology and its gap with foreign countries, emphasizing technological innovation in the development strategy of the new century, and striving to develop mineral processing technology with its own intellectual property rights will help China's mineral resources development and utilization industry Continue to develop in the direction of progress. China's mineral resources are abundant, but its per capita possession is small, ranking 53rd in the world. According to the experts' estimates of the potential value of the resources per square kilometer of land area, China's metal, non-metal, fuel minerals are 1.1 million US dollars, roughly equivalent to the United States, as far as fuel alone, 27% higher than the United States, China The mineral resources have the following characteristics: 1. The total mineral resources are abundant, and the varieties are complete, but the per capita possession is small. 2. Some minerals in the pillar minerals are short of shortages or reserve reserves, while those with larger reserves are some minerals that are not used in large quantities. 3. There are few large and extra large deposits, and there are many small and medium-sized deposits. 4, a single easy to choose rich mines, poor and difficult to choose symbiotic mines, development and utilization is difficult, high production costs, it is difficult to participate in international market competition.
(2) Market demand situation
From the current point of view, the growth of China's national economy still depends to a large extent on natural resources, especially the massive consumption of mineral resources. Since the beginning of the 21st century, China has been in a period of increasing demand for resources. In the 10 years since the beginning of the 21st century, the absolute demand for mineral products in China has increased substantially, and the demand for some major mineral products has doubled from the previous one. Bulk minerals will be difficult to guarantee demand, such as rich iron ore, manganese-rich ore, some non-ferrous metals and chemical minerals have to be imported, while chromium, potassium, diamond and other mineral products are also excessively consumed, the existing reserves are difficult to guarantee demand, will gradually Become a shortage of minerals. In 2010, China's mineral products have faced severe challenges in economic construction to increase demand for mineral products.
(3) The gap with advanced foreign countries
Since the liberation, China's mineral resources development and utilization have made many important achievements, and even in some aspects, it has reached the international advanced level. But overall it is lower than the advanced level of foreign countries. At present, China's annual mining ore volume is 5.3 billion tons, second only to the United States in the world; but the per capita possession of ore is very low, only the world.
1. Resource utilization ratio (output to reserve ratio) is not high. It is only 1/2 to 1/5 of the major mineral resources. The main reason is that some mineral mining grades are too high, such as iron ore, the United States, Canada's mining cut-off grade is 15% to 23%, the former Soviet Union is 15%, China is generally 26% to 30%, resulting in China's Zhangjiakou, Yujia The poor magnetite with a ditch reserve of 2 billion tons is not exploited.
2. The recovery rate of useful minerals in mineral resources is low. According to the statistics of 3498 mines nationwide, the mining recovery rate of iron ore and non-ferrous metal mines in China is 50%-60%; the non-metallic mineral resources are 20%-60%; the coal mines only 34%-50%. Due to the gap between the level of mining and smelting and foreign countries, the total recovery rate of China's mineral resources is only 30% to 40%, which is 10% to 20% lower than the foreign level.
3. The comprehensive utilization rate of mineral resources is low. According to the survey of 845 mines nationwide, the comprehensive utilization rate is only 15%, and the comprehensive utilization rate of 75% of mining enterprises is less than 2.5%. In terms of ferrous metals, the comprehensive utilization rate of foreign advanced mines can reach 80% to 90%, while the domestic average is 50%, which is about 30% to 40% lower than that of foreign countries.
4. The development and utilization of non-metallic mineral resources is backward. Non-metallic mineral resources are diverse in nature, diverse in nature, and widely used. Foreign countries attach great importance to the development and utilization of non-metallic mineral resources. At present, non-metallic minerals in developed countries are 1.5 to 2 times higher than metal mines. China has abundant non-metallic mineral resources. However, the recovery rate of ore dressing is low, the grade of concentrate is low, and there are few super-products. China should put non-metallic mineral resources. Development is extremely important, especially the comprehensive recovery of non-metallic mineral resources associated with metal minerals should receive sufficient attention.
5. The recycling rate of secondary resources is low. At present, the comprehensive utilization rate of industrial solid waste in China is 25.54%. Compared with the economically developed industrial powers, there is a considerable gap. It is also due to the low comprehensive utilization rate. The industrial solid waste of the mining sector has accumulated accumulated over the years. 440.83 million tons, covering an area of ​​179.71 million m2, causing more serious environmental pollution.
V. Development direction
Since the 1980s, countries around the world have continued to innovate in the field of mineral processing technology to promote the development and comprehensive utilization of mineral resources in the country in the direction of sustainable development. Ore crushing: In order to reduce the energy consumption of ore grinding, ultra-fine crushers and high-pressure roller crushers have been developed abroad, and the application of electric field, laser, microwave, high-frequency oscillation, plasma-treated ore for crushing and sorting has been continuously studied. Impact; in the field of mineral separation: the sorting equipment for the joint action of “multiple force fields†has been or is being studied, as well as the multiple principles “combined effect†and “comprehensive sorting technologyâ€, and the introduction of high technology into mineral processing In the field of engineering, for example, the introduction of superconducting technology into magnetic separation, the introduction of electrochemical and control technology into flotation, etc.; in order to maximize the use of mineral resources, countries around the world compete to research and develop non-waste clean production processes; in terms of equipment: for the enterprise Obtaining the largest scale of economic benefits, the research and development of grinding, sorting and solid-liquid separation equipment tends to be large-scale; the detection and control of production processes: process control tends to be automated; technical aspects: after 50 years of development, China's mineral processing Engineering technology has achieved many compelling achievements.
In order to make China's mineral processing engineering technology fully catch up with the world's advanced level in a short period of time, we must pay attention to the following aspects of technological innovation, which will be the key to rapid development across the century. Per capita possesses about 43% of the ore, ranking 80th in the world. Therefore, we should continue to vigorously develop mineral resources, and at the same time we should pay attention to research and solve the main problems behind the development of China's mineral resources.
(1) Research and development of high-efficiency pre-selection equipment, high-efficiency and energy-saving new grinding and grading equipment , and new solid-liquid separation technology and equipment, greatly reducing the energy consumption of ore crushing and solid-liquid separation process, and improving the selected grade.
(2) Research and development of the effects of various energy field pretreatments on ore and sorting, and the development and utilization of various energy field pretreatment new techniques to improve the crushing and sorting accuracy.
(3) In the development of high-efficiency sorting equipment and high-efficiency non-toxic new medicines, the research focuses on the composite force field sorting equipment, the new medicaments with synergistic effects of various components, and the comprehensive sorting technology for treating poor, fine and miscellaneous ore.
(IV) In the research of comprehensive utilization of ore, focus on the development of non-waste cleaning process, strengthen the research on mineral separation, purification and ultra-fine modification in tailings, making it a product needed by the market, transforming from mineral raw material industry to mineral material industry. Provide new technology.
(V) Vigorously introduce high and new technology into the field of mineral processing engineering, focusing on mining bioengineering technology, electrochemical regulation and electrochemical control flotation technology, process automation optimization technology, and research on new technologies for transforming traditional industries with high technology.
(6) Strengthening the research of new edge disciplines combining basic theory with mineral engineering sorting technology, promoting the formation of a new generation of mineral separation theory system, and deriving a new mineral sorting and purification technology system. The guiding ideology for the development of strategic goals is to "based on the domestic status quo and aim at the international advanced level."
According to China's economic development plan, based on the characteristics of China's mineral resources, examine the current status and development trends of mineral processing at home and abroad, and formulate the short- and medium-term development goals of China's mineral processing development as follows: 1. For the utilization of mineral resources in China, there are “three low rates†(reserves, Comprehensive recovery rate, useful components), targeted theoretical research and development of new processes, especially for the complex problems of China's complex, difficult to choose, large mineral resources and the development and utilization of superior mineral resources, in order to form China with Featured mineral processing school. 2. Establish “integrated mineral processing theory system†(1) Combine basic theories related to physics, chemistry, geological minerals, fluids, magnetism and mineral processing; (2) High-tech such as bioengineering, high-energy technology, microelectronics, super The combination of the guidance and the beneficiation process; (3) the combination of multiple force fields, thereby deriving a highly efficient new beneficiation technology system. 3. Carry out the research on the “digital, optimization and automation†mechanism of the beneficiation project, and develop the current mineral processing project into “theory science†from the stage of “experimental scienceâ€. Vigorously promote the popularization and application of computers in the field of "masonry modeling, simulation, optimization, automation".
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