Ore separation is the process of separating useful minerals from gangue or harmful minerals in ores to improve the grade and recovery rate of useful minerals. Yesterday we introduced four different methods of ore separation, and today we will continue to introduce another four ore separation technologies. Electrostatic separation method Basic principle and working mechanism of electrostatic separation Electrostatic separation is a mineral separation method based on the difference in surface charge of mineral particles. Under the action of the electric field, the charged mineral particles will move to the opposite electrode to achieve separation. The electrostatic separation process usually includes a preparation stage (crushing, grinding, grading), a drying and charging stage (charging the mineral particles), a separation stage (separation in the electric field), and a washing and collection stage. Types of ores with high electrostatic separation efficiency Electrostatic separation shows high efficiency in processing some specific types of ores, especially those with obvious differences in conductivity. These ores include: Sulfide minerals: such as pyrite, sphalerite, etc., which can remove some gangue by electrostatic separation before grinding and flotation. Metal oxide minerals: such as hematite, limonite, etc., these minerals can be effectively separated by electrostatic separation under appropriate conditions. Certain non-metallic minerals: such as graphite, silica, etc., due to their good conductivity, electrostatic separation can be used as an effective separation method. Electrostatic separation and flotation are both commonly used beneficiation methods in mineral processing. They have their own characteristics and applicability when dealing with fine powders. Characteristics of electrostatic separation Electrostatic separation is based on the difference in conductivity of mineral particles in an electric field for separation, and is suitable for processing minerals with large differences in conductivity. Electrostatic separation can process minerals with fine particles, complex components and thin layers, and has good separation effects, but the equipment cost is high, the operation is complex, and it has high requirements for the skills of operators. Characteristics of flotation The flotation method relies on the differences in the physical and chemical properties of different mineral surfaces. By adding flotation agents, the target mineral surface is made hydrophobic and suspended in the foam to float up, thereby achieving separation. Flotation shows a good purification effect when dealing with non-metallic minerals such as silicon micropowder, and the process flow is relatively simple and the equipment requirements are low. However, flotation may require a large amount of reagents and have a certain impact on the environment. Applicability comparison For the treatment of fine powders, electrostatic separation can usually provide higher separation accuracy and selectivity, especially when treating minerals with significant differences in conductivity. Flotation is suitable for fine powders that can be effectively separated by adjusting the surface properties, and operates under acid-free conditions, with less impact on the environment. In summary, if there are obvious differences in conductivity between the mineral particles of the fine powder, electrostatic separation may be a more appropriate choice. If the fine powder can be effectively separated by adjusting the surface properties and has high requirements for environmental protection, flotation may be more applicable. In practical applications, it is also necessary to consider economic efficiency, environmental impact and the specific characteristics of the ore to determine the most appropriate beneficiation method. Advantages of electrostatic separation The advantage of electrostatic separation is that it can handle minerals with differences in conductivity, and has relatively low energy consumption, which is suitable for dry and conductive materials. Technical challenges faced by electrostatic separation in ore processing Uneven conductivity of minerals: The conductivity of natural minerals is often uneven, which may lead to poor electrostatic separation results. In order to improve the separation efficiency, it is necessary to precisely control the electric field strength and distribution, as well as optimize the pretreatment process of mineral particles. Size effect of mineral particles: Small particles of minerals tend to aggregate during the electrostatic separation process, affecting the separation effect. Therefore, it is necessary to research and develop electrostatic separation technologies that can handle fine particles. Changes in mineral surface properties: During the electrostatic separation process, chemical or physical changes may occur on the surface of mineral particles, affecting their conductivity and the final separation effect. This requires an in-depth understanding and control of the surface behavior of minerals. Corrosion resistance and maintenance issues of equipment: Since the electrostatic separation process involves water and electrolyte solutions, the equipment materials must have good corrosion resistance. At the same time, the maintenance and life of the equipment are also technical difficulties that need to be overcome in practical applications. Energy consumption and cost control: Electrostatic separation equipment usually requires a large amount of electrical energy input. How to reduce energy consumption and operating costs is the key to improving the competitiveness of electrostatic separation. Environmental impact: The treatment of wastewater and waste residues generated during the electrostatic separation process is a concern for environmental protection, and effective measures need to be taken to reduce the negative impact on the environment. In practical applications, electrostatic separation is often used in combination with other mineral separation methods to optimize the entire mineral separation process and improve the quality and economic benefits of the final product. Chemical beneficiation Chemical beneficiation uses chemical reagents to react with minerals in the ore to change the chemical composition or physical state of the minerals, thereby achieving separation. This method is suitable for processing poor, fine, impure and other difficult-to-select mineral raw materials, and can improve the comprehensive utilization rate of minerals. The advantages include strong processing capacity and wide adaptability, but the disadvantages are that it may involve environmental pollution and equipment corrosion problems, and the processing cost is relatively high. Applicable ore types for chemical beneficiation Chemical beneficiation is mainly suitable for processing ores that can effectively separate useful minerals and gangue minerals through chemical reactions. The following are several types of ores, in which chemical beneficiation shows better treatment effects: Oxidized copper ore: Chemical beneficiation methods, such as acid leaching and alkaline leaching processes, can effectively extract copper and significantly improve the recovery rate. Difficult to select complex copper ores: For these ores, chemical beneficiation can improve beneficiation efficiency and economic benefits by optimizing reagent formulas and process conditions. Complex intercalated manganese ore: Chemical beneficiation, including leaching and precipitation, is suitable for processing complex intercalated manganese ore because these methods can effectively separate the minerals by using the differences in the chemical properties of the minerals. Phosphate ore with special chemical properties and complex impurity composition: Chemical beneficiation can separate and enrich the minerals by adding chemical reagents to induce chemical reactions between the phosphate ore and the impurities, and is suitable for purifying high-quality phosphate ore products. These ore types usually ave complex mineral compositions or are closely combined with the gangue, making it difficult for traditional physical beneficiation methods to achieve satisfactory separation effects. Chemical beneficiation achieves effective separation by changing the chemical state of the minerals and breaking the bonds between the minerals. In practical applications, the effect of chemical beneficiation is affected by the characteristics of the ore, the selection of chemical reagents and the process conditions, so these factors need to be considered comprehensively when designing the beneficiation process. Microbial beneficiation method Microbial beneficiation method uses the metabolic activities of microorganisms to extract valuable metals from ores. This method is environmentally friendly, low-cost, and can process complex polymetallic minerals. The development trend of microbial beneficiation technology is to improve flotation recovery, reduce beneficiation costs and reduce environmental pollution. Ore types applicable to microbial beneficiation Microbial beneficiation, also known as bacterial beneficiation, is a beneficiation method that mainly uses microorganisms such as iron-oxidizing bacteria, sulfur-oxidizing bacteria and silicate bacteria to remove iron, sulfur and silicon from minerals. This technology is suitable for the treatment of a variety of ores, especially in the treatment of low-grade copper, uranium ores, low-grade gold and silver ores and some difficult-to-benefit ores. Microbial beneficiation technology can effectively improve the leaching rate of ore, reduce beneficiation costs, and to a certain extent increase the grade of ore and improve resource utilization efficiency. In practical applications, microbial beneficiation has been used in mines in many countries, such as gold mines in Australia, copper mines in Canada and phosphate mines in China. These cases show that microbial beneficiation technology has practical application value in improving metal recovery and reducing environmental pollution. Advantages of microbial beneficiation Environmental protection: Microbial beneficiation uses the biological metabolic capacity of microorganisms, reduces the use of chemical reagents, and reduces environmental pollution. Cost-effectiveness: Compared with traditional beneficiation technology, microbial beneficiation technology usually has lower operating costs because it does not require expensive equipment and complex process flows. Adaptability: Microorganisms can survive in harsh environments and have strong adaptability, which enables microbial beneficiation technology to process a variety of complex and low-grade ores. High efficiency: Microbial beneficiation technology can improve beneficiation efficiency and metal recovery, especially showing unique advantages when processing difficult-to-benefit ores. Disadvantages of microbial beneficiation method Slow oxidation rate: Microorganisms oxidize minerals relatively slowly, which may lead to longer leaching time and affect production efficiency. Poor controllability: The microbial growth environment is greatly affected by factors such as temperature, pH value, and oxygen content. Changes in these factors may affect the separation efficiency of ores, making it difficult to accurately control the microbial beneficiation process. Technical challenges: The research and application of microbial beneficiation technology still faces some technical challenges, such as the screening, cultivation and optimization of microbial strains. Environmental adaptability: Some microorganisms have slow growth rates and poor environmental adaptability, which directly affects the leaching efficiency. The advantages of microbial beneficiation method are mainly concentrated in its environmental friendliness and cost-effectiveness, while the disadvantages are reflected in the processing speed and controllability. With the development of biotechnology, these shortcomings are expected to be overcome through technological innovation. Technical Challenges of Microbial Mineral Processing Although microbial mineral processing has obvious advantages in terms of environmental protection and cost-effectiveness, it still faces some technical challenges in practical application: Strain selection and optimization of culture conditions: Finding efficient and stable microbial strains and optimizing their culture conditions to ensure performance and stability in industrial-scale production is a key challenge. Different ores and environmental conditions require specific microbial strains, and the control of culture conditions is crucial for microbial activity. Understanding of bioleaching kinetics and mechanisms: In-depth understanding of the mechanism of action of microorganisms on minerals and leaching kinetics can help improve mineral processing efficiency and select suitable process parameters. At present, the understanding of these mechanisms and kinetics is not comprehensive enough, which limits the further development of microbial mineral processing technology. Technical difficulties in large-scale production: Scaling up the laboratory-scale microbial mineral processing process to the industrial production scale requires overcoming a series of technical difficulties, including large-scale cultivation of microorganisms, maintaining a suitable growth environment, and dealing with possible technical problems. Influence of environmental factors: The growth of microorganisms in the natural environment is affected by many factors, such as temperature, pH value, oxygen supply, etc. These factors are difficult to control in industrial production and may affect the activity of microorganisms and mineral processing effects. Economic evaluation: Although microbial beneficiation has cost advantages in theory, in actual operation, how to ensure the economy of the whole process, especially in terms of initial investment and operating costs, is still a problem that needs to be solved. These challenges require interdisciplinary research cooperation, including experts in fields such as microbiology, geology, chemical engineering and environmental science, to work together to promote the commercialization and industrialization of microbial beneficiation technology. AI beneficiation Method Definition and basic principles of artificial intelligence sorting technology Artificial intelligence sorting technology refers to the use of artificial intelligence algorithms, especially machine learning and deep learning technologies, to analyze the physical or chemical properties of mineral materials, so as to achieve automatic classification and sorting. These technologies are able to process large amounts of data, self-learn and optimize sorting strategies, and improve sorting efficiency and accuracy. Scope of application of artificial intelligence sorting minerals Artificial intelligence sorting technology is increasingly widely used in the field of mineral processing, and is suitable for the sorting of a variety of minerals. According to the latest research and application cases, artificial intelligence sorting machines have demonstrated their advantages of high efficiency, precision and environmental protection in many fields such as non-metallic ores, non-ferrous metal ores, and rare earth metal ores. For example, artificial intelligence sorting technology has achieved remarkable results in the sorting of non-metallic ores such as talc and fluorite, improving the utilization rate of ore resources and optimizing the industrial structure. Successful application cases Intelligent sorting of wollastonite: A large domestic wollastonite company adopted the artificial intelligence sorting equipment of Mingde Optoelectronics to achieve accurate sorting of wollastonite ore, improve the control level of finished product loss on ignition, and the concentrate yield and stable sorting effect met customer expectations. Sorting of non-metallic and metallic ores: As a high-tech equipment based on the principle of photoelectric sorting, ore color sorter is widely used in non-metallic minerals such as fluorite, barite, quartz, potassium feldspar, calcite, and metal ores under certain specific conditions, showing strong performance. Advantages of AI Sorting Improve sorting accuracy and efficiency: AI sorting technology can achieve fast and accurate classification of different minerals through image recognition, machine learning and other means, and improve sorting accuracy and efficiency. Automated operation: The AI ​​sorting system realizes the automated sorting process, reduces manual intervention, reduces labor intensity, and improves production safety. Flexible configuration: AI sorting equipment can be flexibly adjusted according to the sorting needs of different types of minerals, has strong adaptability, and can be widely used in various mineral sorting scenarios. Environmentally friendly: Through precise sorting, the disorderly mining of low-grade ores can be reduced, waste emissions can be reduced, and it is conducive to the sustainable development of the mining industry. Disadvantages of AI Sorting Technical threshold: The research and development and implementation of AI sorting technology require high technical knowledge and professional talents, which may limit its application in some small or technologically backward enterprises. Initial investment cost: The purchase cost of high-performance AI sorting equipment and related software systems is high, which may increase the initial investment burden of enterprises. Data dependence: The performance of AI sorting systems depends largely on a large amount of high-quality training data, and data collection and processing may be a challenge. In summary, artificial intelligence sorting technology has significant advantages in improving the efficiency and quality of mineral processing, but its application also faces technical and cost challenges. With the continuous development of technology and the gradual reduction of costs, it is expected that artificial intelligence sorting technology will be more widely used in the mining industry. Mingde Optoelectronics Technology Co., Ltd. was the first to introduce artificial intelligence and big data technology in the field of mining sorting in China, opening up the artificial intelligence era of ore sorting, greatly expanding the scope of application of photoelectric sorting, and is applicable to common metal and non-metallic ores, and greatly improving the accuracy of ore sorting. The heavy-duty ore sorting machine launched by the company can sort ores with a particle size of 8-15 cm, reducing the waste caused by repeated crushing of ore for sorting, while greatly increasing the output of ore sorting.   So far, we have briefly introduced the eight common sorting methods on the market, and we will continue to share more mining knowledge with you later.

Calcium carbonate (CaCO3 for short) is an inorganic compound, commonly in the form of white solid powder or granules, and is one of the most abundant substances on earth. It is widely distributed in nature and is the main component of rocks, corals, pearls and the shells of many organisms. Calcium carbonate is chemically insoluble in water, but can release carbon dioxide gas in an acidic environment. Calcium carbonate can be divided into several types according to different production methods, particle size, morphology and uses. The focus of this discussion is to understand the difference between heavy calcium carbonate and light calcium carbonate, both of which are widely used in industrial applications. Heavy calcium carbonate Heavy calcium carbonate (GCC for short) is made by physical methods, usually mechanical crushing of natural minerals such as calcite, limestone, chalk, and shells. It is characterized by irregular particle shape, wide particle size distribution, and an average particle size of 5-10μm. Heavy calcium carbonate has a large bulk density, generally between 0.8-1.3g/cm³, and a low oil absorption value, generally 40-60mL/100g. Light calcium carbonate Light calcium carbonate (PCC for short) is produced by chemical precipitation. Its particles are regular in shape and can be regarded as monodisperse powders. The particle size distribution is narrow and the average particle size is generally 1-3μm. The bulk density of light calcium carbonate is small, generally between 0.5-0.7g/cm³, and the oil absorption value is high, generally 60-90mL/100g. Active calcium carbonate Active calcium carbonate is obtained by surface modification on the basis of ordinary calcium carbonate. It is hydrophobic and suitable for occasions with specific needs. Difference Production method: Heavy calcium carbonate is mainly produced by physical crushing, while light calcium carbonate is produced by chemical precipitation. Particle size and shape: The particle size and shape of heavy calcium carbonate are irregular, while the particle size and shape of light calcium carbonate are regular. Bulk density: The bulk density of heavy calcium carbonate is greater than that of light calcium carbonate. Oil absorption value: The oil absorption value of heavy calcium carbonate is lower, while the oil absorption value of light calcium carbonate is higher. Whiteness: The whiteness of light calcium carbonate is generally higher than that of heavy calcium carbonate. Surface modification: Activated calcium carbonate has been surface modified and is hydrophobic. Industrial application Calcium carbonate is widely used in industry. It can be summarized into the following major areas: 1. Rubber industry In the rubber industry, calcium carbonate is used as a filler and reinforcing agent in large quantities. It can effectively improve the hardness, wear resistance, tensile strength, tear resistance and aging resistance of rubber. In addition, calcium carbonate also helps to reduce production costs and increase the output of rubber products. 2. Plastic industry In the plastic industry, calcium carbonate also plays an important role. It can improve the hardness, wear resistance, heat resistance and weather resistance of plastics, while also reducing production costs and improving production efficiency. 3. Construction industry In the construction industry, calcium carbonate, as a raw material for cement, can significantly improve the compressive strength, flexural strength and durability of cement. It can also improve the construction performance of cement and improve the seismic performance of buildings. 4. Agricultural field In the agricultural field, calcium carbonate is used as a fertilizer and feed additive, which can improve the disease resistance of crops, promote root growth and soil acid-base balance, and also improve the yield and quality of crops. 5. Medical field In the medical field, calcium carbonate is used as a calcium supplement and antacid to treat diseases such as osteoporosis and rickets. It can also be used as a pharmaceutical excipient for the manufacture of tablets, capsules and injections. 6. Environmental protection field In the environmental protection field, calcium carbonate is used as an adsorbent and precipitant to remove harmful substances from water, reduce the hardness of water bodies, and improve water quality. It can also be used in waste gas treatment and soil remediation. 7. Cosmetic industry In the cosmetics industry, calcium carbonate is used as an additive for beauty products, which can improve skin texture, increase skin elasticity, and make the skin smoother and more delicate. 8. Other fields In addition to the above application fields, calcium carbonate is also widely used in ceramics, glass, pigments and other industries. It can improve the hardness, wear resistance, corrosion resistance and transparency of materials and other performance indicators. Processing Processing of light calcium carbonate Light calcium carbonate is produced by chemical reaction precipitation. Its production process mainly includes: Calcination stage: calcine the limestone raw material to generate calcium oxide and carbon dioxide. Digestion stage: put the calcined calcium oxide into a continuous digester and add water to digest it to obtain calcium hydroxide emulsion. Carbonization stage: react the calcium hydroxide emulsion with carbon dioxide to generate calcium carbonate precipitation. Dehydration and drying stage: dehydrate and dry the calcium carbonate precipitation to obtain dry calcium carbonate powder. Crushing and screening stage: crush and grade the dried calcium carbonate through crushing and screening equipment to obtain the product of the required fineness. Packaging stage: package the graded calcium carbonate powder to obtain the final product. Processing of heavy calcium carbonate The production process of heavy calcium carbonate generally includes the following steps: Crushing: use a crusher to coarsely crush raw materials such as calcite for subsequent fine grinding. Sorting: generally use hand selection, magnetic separation equipment or photoelectric separation equipment to remove impurities from the ore. CCD Sensor Based Ore Color Separator The color sorter and artificial intelligence sorting launched by Mingde Optoelectronics Technology Co., Ltd. have excellent performance in the sorting of heavy calcium carbonate. They can accurately compare the sorted materials according to the surface characteristics of the ore to achieve accurate sorting. AI Sorting Machine The heavy-duty sorting machine launched by the company can sort large-particle ore, which not only avoids over-crushing of the ore, but also increases the output of ore sorting. Heavy Duty AI Sorting Machine Fine grinding: Fine grinding is carried out by Raymond mill, pendulum mill, roller mill and other equipment to obtain fine limestone powder. Classification: The powder is graded by the classifier, and the powder that meets the particle size requirements is packaged and stored as a product, and the powder that does not meet the requirements is returned to the mill for re-grinding. Packaging and storage: The powder that meets the particle size requirements is packaged and stored to complete the entire production process. As a multifunctional and widely used material, calcium carbonate not only plays an important role in the traditional industrial field, but also shows new possibilities in emerging fields. With the development of science and technology, the application prospects of calcium carbonate will be broader.