1. Study on the relationship between surface properties of phosphate rock and mineral structure and geological genesis. It is of great guiding significance to study the relationship between the crystal structure and surface properties of phosphate rock and the floatability and machinability of minerals.
2. Development of flotation reagents for phosphate rock. Over the years, various collectors, inhibitors and flocculants have been developed and a series of products have been formed, some of which have been applied in industry. For example, W-98, OT- 1 and OT-3 have been successfully applied to Haikou and Kunyang phosphate mines, reaching the domestic leading level. The developed collector W-0 1 was listed as a national famous product and won the third prize of scientific and technological progress of the Ministry of Light Industry. The developed WHL- 1 flocculant won the third prize of 1999 WISCO Scientific and Technological Progress Award; The synergist C.Z.S developed by the provincial key project "Study on Normal Temperature Flotation Process of Phosphate Ore" can reduce the flotation temperature of Fangmashan Phosphate Mine from 40℃ to 25℃, and each ton of raw ore can generate economic benefits in 2.4 yuan, reaching the domestic leading level.
3. Enrichment technology and process development of magnesium-silicon low-grade phosphate rock. Since 1986, the forward-reverse flotation process, reagents and supporting technologies suitable for treating low-grade magnesium-siliceous phosphate rocks in Hubei, Hunan, Jiangxi and Yunnan provinces have been developed and improved. Successively, the continuous expansion beneficiation tests of phosphate rocks such as Fangmashan, Baokang, Dayukou, Wang Ji, Haikou and Xixi were carried out. The scale-up test of direct-reverse flotation in Dayukou Mine and the industrial test of direct-reverse flotation in Wang Ji Phosphate Mine have reached the international advanced level. The project "Study on Flotation Industrialization of Yunnan Medium-grade Silicon-Calcium Phosphate Ore" is recognized as the leading level in China, and it is the project with the strongest financial support among the "provincial-school cooperation projects" in Yunnan Province.
4. Electrochemical study of flotation. The electrochemical mechanism of sulfide flotation and the electrochemical treatment method of flotation wastewater were studied. The key scientific research project of the Provincial Science and Technology Commission "Study on Enhancing Phosphorus Flotation by Electrochemical Method" has reached the "domestic leading level" through appraisal.
This discipline is in a leading position in the country in the combination of theory and practice, technological innovation and academic level of chemical ore flotation. Many of the projects we study are problems that cannot be solved by scientific research institutes or research institutes or for a long time after they are put into production. For example, large phosphate rocks such as Haikou and Kunyang in Yunnan are extremely difficult to separate. Although it has been studied for many years, even the national key issues in the Eighth Five-Year Plan have not been solved. After several years of research, the subject has formed a set of technology from technology to medicine. The test results not only completely exceed the technical and economic indicators required by the provincial science and technology department, but also give full play to the advantages of environmental engineering in our institute, realize no wastewater discharge, make important contributions to the development of pillar industries in Yunnan, and are highly praised by the Yunnan science and technology department. It also attracted great attention at the annual meeting of mineral processing of China Mining Association. Performance optimization and functionalization of natural minerals is an important way to increase the added value of resources. This study takes phosphate rock and clay minerals as the research objects, focusing on the following aspects: (1) the relationship between the composition of materials and environmental performance; (2) Composite mineral materials and molding technology (3) Mathematical model in the preparation process of functional mineral materials.
On the basis of studying the crystallization chemistry of phosphate rock, new environmental protection materials were prepared by various modification technologies. The key project of Hubei Science and Technology Department "Study on Modified Phosphate Rock Composite Adsorbent" has reached the leading level in China. The preparation and identification of the provincial education department "Treatment of chromium-containing wastewater with modified phosphate rock", the Italian Science Foundation cooperation project "Evolution of volatile components in apatite" and the provincial education department's major project "Preparation of nano-apatite whisker organic hybrid and its application in composite materials" have all been basically completed. In the development of clay-apatite composites, high-performance clay minerals such as bentonite and rectorite and their composites with apatite were prepared by new technologies such as crosslinking and interfacial activation, which can be used as fillers, catalytic materials and antibacterial materials. For example, Hubei provincial fund project "Study on the adsorption mechanism of phosphorus and phenol by some clay mineral composite adsorbents", "Preparation of rectorite antibacterial material and its antibacterial mechanism", provincial science and technology department key project "Study on the treatment of industrial wastewater with rectorite", provincial education department outstanding young and middle-aged talent project "Development of rectorite antibacterial agent", Wuhan major project "Development of nano-mineral environmental materials and wastewater treatment process" and "Development of Chifeng natural zeolite activation process and solid desiccant". The research and development of industrial wastewater treatment with mineral environmental materials has been piloted in Jingmen and made good progress. He published 6 papers and was included by SCI, EI, ISTP, etc. In the United States and China, 65,438+0 invention patents were granted and 65,438+0 invention patent applications were published.
In the preparation process of the above-mentioned mineral materials, superfine and superfine grinding technology are particularly critical. Because of the small particle size, large specific surface area and high crushing energy consumption, it is of great theoretical significance and practical value to study the relationship between variables and its mathematical model in the crushing process for revealing the crushing mechanism, improving crushing efficiency, reducing energy consumption and realizing optimal control. The national natural science foundation project "Mathematical model of spiral classifier and its application in grinding circuit control" and the science and technology development plan project of Ministry of Chemical Industry "Study on wear mechanism and wear law of ball mill" were completed. The basic concepts of "mixing index" and "limit mixing number" in the classification process were put forward for the first time, the model of "particle size characteristic criterion and evaluation function" was established, and a new academic viewpoint of "compound superposition principle of ball wear" was put forward and developed. The research results won the first and second prizes of outstanding academic papers in Hubei Province and were included in ei and SCI.
This research direction has formed its own characteristics. In the aspect of sewage treatment, it is the first to apply the independently developed mineral materials to industrial experiments, which is at the leading level in China. The developed clay mineral composite adsorbent can treat a variety of high and low concentration industrial wastewater, and the treatment cost is lower than other methods. The useful components in wastewater can be recovered during operation, which promotes the application of clay minerals in environmental engineering and is unique in the province. The basic and applied research of phosphate rock in cooperation with Italy and the United States is at the advanced level in the world. The patent of modified phosphate rock in the recovery and treatment of heavy metal wastewater is the first in China, and the industrial application research has begun. The talents trained in this research direction will certainly make due contributions to the development of basic theoretical research of functional mineral and rock materials and the industrial transformation of material preparation. This research direction has the characteristics of multidisciplinary theory and technology synthesis. Mineral biotechnology is an advanced technology that comprehensively utilizes the principles and methods of biological and chemical engineering to treat poor and miscellaneous ores and extract precious metals. Mineral biotechnology has the characteristics of low cost, little pollution and wide treatment objects (not limited to specific minerals). It is one of the important directions of mineral processing development in the future. The research and development of this technology is of great significance to the development and utilization of a large number of idle lean ore, refractory ore and abandoned tailings resources in China and the control of environmental pollution.
1 and study on bioleaching process of low-grade copper ore. Copper resources in China are mainly poor and scattered in remote areas; It is uneconomical to treat these copper mines with traditional mineral processing-smelting process. However, for a long time, the self-sufficiency rate of copper in China is seriously insufficient. Microbial heap leaching or in-situ leaching process has the advantages of low cost, little pollution and simple operation. The large-scale production practice in the United States and other countries proves that heap leaching-extraction-electrowinning of lean ore is a profitable industry. It is of great practical significance to carry out the application research of this technology in China's geographical environment for utilizing China's poor ore resources and alleviating the pressure of insufficient copper self-sufficiency in China. The "863" project "Research on Microbial Heap Leaching Technology in Dexing Copper Mine" jointly carried out by our institute and Central South University has achieved important results.
2. Study on microbial treatment technology of refractory gold ore. The arsenic-bearing and carbon-bearing micro-disseminated encapsulated gold deposit is recognized as a refractory metallurgical deposit in the world. Traditional treatment methods include oxidation roasting, pressure oxidation and chemical oxidation. These methods all have problems such as large investment, high production cost and environmental pollution. Biological treatment technology can avoid these shortcomings. There are a large number of refractory metallurgical mines in Guangxi, Yunnan, Guizhou, Sichuan and Shaanxi. Biological treatment technology will provide a new way for the development and utilization of such mineral resources. The key project of Hubei Province "Study on Microbial Oxidation Treatment of Refractory Gold Ore in Chongyang" completed by our institute studied the leaching mechanism of gold in chalcopyrite-pyrite-arsenopyrite system under the action of bacteria, the changing law of mineral interface properties and the technological parameters of flotation separation. The leaching rate of gold increased from 46% to 90%, which was appraised as "domestic leading level" by the provincial science and technology commission.
3. Study on microbial treatment technology of low-grade phosphorus resources. China is rich in phosphorus resources, but the resource conditions are poor, and most of them are of low grade, so they cannot be directly used for fertilizer production. If we rely on traditional mineral processing to enrich, the cost will increase greatly, which has long plagued the development of phosphate fertilizer industry in China. There are a large number of low-phosphorus tailings in Yunnan, Guizhou and Hubei. These phosphorus resources are directly converted into phosphate fertilizer which can be absorbed by plants by using phosphorus-solubilizing microorganisms. Experiments show that phosphate fertilizer made from low-grade phosphate rock can obviously increase the yield of rape and wheat, and find a new way for the utilization of these low-grade phosphorus resources.
Study on the application of microbial technology in environmental protection. Biotechnology has great application potential in environmental protection. This study is an extension of mineral biotechnology in environmental protection, focusing on the treatment of inorganic metal and heavy metal pollution. The traditional treatment method is neutralization precipitation, but it has some defects, such as large chemical consumption, incomplete metal precipitation, difficult recovery of precipitated metal, and easy to cause secondary pollution (wastewater). Microorganisms or microbial products such as bioflocculants can adsorb or dissolve metals, thus achieving the comprehensive effect of pollution control and recovery. Biotechnology can also treat all kinds of domestic sewage, industrial wastewater, solid waste, soil organic pollutants and so on. Aerobic composting, anaerobic fermentation and other methods can achieve the purpose of comprehensive management, turning waste into treasure and recycling energy. 19th century, mineral processing is not an independent discipline, but an integral part of the mining discipline system. Around 1900, metallurgy was separated from the big mining industry and developed into an independent discipline. After 1930s, mineral processing began to develop into a relatively independent engineering discipline.
The early mineral processing (mineral processing) was based on the technological process of the concentrator. It is essentially a reflection of mineral processing, and consists of three major plates: mineral processing methods (mainly flotation, gravity separation and magnetic separation), auxiliary processes (such as crushing, dehydration and drying) and detection and control of mineral processing. Therefore, it has strong practicability.
In the second half of the 20th century, with the rapid development of the world economy and the rapid development of science and technology, as well as the gradual depletion of high-grade and easy-to-select mineral resources, various disciplines in the field of resources and materials engineering have undergone obvious adjustments and changes. For example, the metallurgical discipline is gradually moving closer to the material discipline and transforming. Mineral processing is no exception. It has experienced a series of changes and adjustments, and is facing great challenges.
The grade of mined ore is getting lower and lower. Taking copper resources as an example, the average grade of selected copper mines in the United States was in the 1930s and 1940s! 1.5, now only 0.6%, and the grade of copper ore treated by individual concentrator is as low as 0.35%. It is estimated that if the grade is reduced from 1.5% to 0.5%, the energy consumption of mineral processing will increase by 1 times, and the further reduction of grade will increase the energy consumption of mineral processing even more. The problem lies not only in this, but also in the environmental problems caused by the reduction of ore grade. Because smelting 1 ton of metallic copper requires about 200 tons of copper ore with a grade of 0.5%, every time 1 ton of copper ore is produced, about 3 tons of waste rock is produced. With the dilution of selected ore, the treatment of tailings and waste residue will become an important factor restricting the development of mineral processing. The chemicals used also have an impact on the environment. It can be said that the current mineral processing is under the severe constraint of the triangle of "economy-energy consumption-environment".
The proportion of refractory minerals is increasing. With the depletion of rich and easy-to-beneficiate mineral resources, a series of mineral resources with complex genetic relationship and fine disseminated granularity have been put on the agenda. This problem is particularly prominent in China. A large number of weakly magnetic iron ores in China cannot be effectively separated because of the fine disseminated particle size of iron minerals and associated minerals (less than 10 ~ 30 μm). Not only iron ore, such as manganese ore, phosphate rock, bauxite and so on, have the same problem. Although the separation technology is an unsolved problem, the operations such as fine grinding and dehydration are far from mature. Facing the severe realistic challenge, the discipline of mineral processing has been and is still undergoing tremendous adjustment and change. Some technologies suitable for treating lean and complex ores and directly extracting useful components are being developed and applied.
The object of mineral processing has expanded from natural mineral resources to the recovery and utilization of secondary resources. All kinds of solid waste, such as tailings, slag, fly ash, metal waste, electrical waste, plastic waste, domestic waste and even soil, have become the objects of treatment and are transformed into useful resources after treatment. With the development of modern science and technology and the progress of human society, it is necessary to develop ultra-pure, ultra-fine mineral raw materials and materials with special functions. Another example is nonmetallic mineral materials with special functions, such as graphite, mica and asbestos, and ultrafine metal oxide powder, which all need special processing methods different from traditional methods, that is, the so-called deep processing technology. In fact, in the second half of the 20th century, mineral processing technology has gradually broken through the traditional framework of mechanical processing. In the processing of metallic and nonmetallic minerals, chemical extraction and the combination of bioengineering and mechanical processing have long been commonplace. The deep processing of nonmetallic minerals further expands and enriches this combination, such as ultrasonic stripping of kaolin, organic-inorganic intercalation of graphite and various layered minerals.
The traditional processing technology has also undergone tremendous changes. Ultrafine grinding and classification are used more and more; Interface separation method has become the main means of fine particle separation; Filter press and centrifugal force field play an important role in solid-liquid separation of ultrafine particles; Various molding and packaging processes are becoming more and more important. The task of mineral processing has also changed. Mineral processing not only provides qualified mineral raw materials for various industries, such as concentrate powder or intermediate products, but also extends to industries that can produce ultra-pure, ultra-fine and special functional mineral materials and mineral products. Mineral materials engineering is mainly a technology that takes nonmetallic ores or minerals as raw materials (or substrates) and makes inorganic nonmetallic materials and devices with certain physical and chemical properties through certain deep processing technology. Mineral materials have great application prospects, such as zeolite solar panels, montmorillonite desiccant, pyrophyllite high-temperature insulation and missile sealing materials, paragonite sealing materials, hydroxyapatite bone materials, diatomite dental materials, volcanic refractory materials, etc.
Further analysis of the unit operations involved in modern mineral processing engineering generally includes: crushing, classification, preparation of ultrafine particles, physical separation (gravity separation, magnetoelectric separation, photoelectric separation, radioactive separation, etc. ), interface separation such as flotation, chemical treatment and biological extraction, solid-liquid separation (precipitation, filtration and drying), molding and granulation, gas-solid separation-dust removal, material storage and transportation, etc. These unit operations are compared with metallurgical engineering, chemical engineering, environmental engineering, inorganic material engineering and particle technology, as shown in the following table (omitted). Through the analysis of the table, it can be found that the unit operations listed in the table have strong universality in six different engineering fields, and many unit operations are the same. From this, we can see the organic connection and cross relationship between these six different engineering fields. Therefore, it can be said that mineral processing is closely related to metallurgy, chemistry, inorganic materials, environmental engineering and particle technology, no matter from the historical development of mineral processing engineering or from the similarity between the above disciplines. In particular, all kinds of mechanical processing and processing unit operation of particles have become almost the same part of these engineering and technical disciplines. The main difference between these engineering fields is only the different objects. No wonder in Europe, these general physical processing unit operations are often referred to as machining technology or process technology. In chemical engineering, the juxtaposition of machining technology and separation technology includes almost all chemical unit operations except chemical reaction engineering. In mineral processing engineering, the juxtaposition of mechanical processing technology and mineral separation technology covers almost all unit operations. Therefore, from the perspective of modern discipline system, it can be considered that mineral processing engineering consists of separation and enrichment technology, mechanical processing technology and process simulation control. Looking back at history, it is not difficult to see that mineral processing was originally only a branch of mining or metallurgical engineering, but later it was separated from mining or metallurgical engineering due to the rapid expansion of mineral resources development and utilization, and developed into an independent discipline. Now people have observed the regression and blending between disciplines. With the exhaustion of mineral resources and the refinement of their relationship, chemical treatment becomes more and more important, and chemical treatment is the main technological process of extraction metallurgy. At present, extractive metallurgy and chemical engineering are also blending. Mineral material engineering or technology involved in modern mineral processing is also very close to inorganic material engineering. The treatment of mineral processing waste residue, tailings and wastewater itself is the main content of environmental engineering, not to mention mineral processing technology (including separation technology) has found its own position in environmental treatment engineering. With the development of science and technology today, the boundaries between disciplines tend to cross, and the development of market economy requires the scientific and technological community to have greater adaptability and adaptability. In this case, as long as it is not limited by the research object, mineral processing technology can be effectively applied to the above-mentioned various engineering and technical fields. On the other hand, absorbing and utilizing practical experience and research results in other engineering and technical fields can promote the further development of mineral processing. It can be said that the interdisciplinary research and application of mineral processing technology is the biggest challenge and opportunity before us.