I. Overview Iron ore beneficiation methods can be divided into two types of single and combined. The single method mainly includes (weak magnetic separation, strong magnetic separation), magnetic roasting magnetic separation, reselection, flotation, and electric selection. The joint method is divided into two types, serial and parallel, according to different methods of connection. The former is used in series by different methods to recover different useful ingredients; the latter is used in parallel with different methods to treat different grades of ore separately. Iron ore includes magnetite ore, hematite ore, magnet-red (Ring) iron ore, limonite ore, siderite ore, composite iron ore, and the like. The beneficiation method and process flow are described as follows. Second, magnetite ore beneficiation method and process Magnetite ore is mainly deposited metamorphic magnetite ore. Most of the iron minerals in the ore are magnetite, mainly composed of fine-grained inlays; the gangue minerals are mainly silicate minerals such as quartz or amphibole, and some contain more iron silicate. Since magnetite ore is a strong magnetic mineral, high-grade, high-recovery iron concentrate can be obtained by weak magnetic separation. Many large and medium-sized magnetic separation plants often use a grinding magnetic separation process when the grinding particle size is larger than 0.2-0.3mm. When less than 0.2-0.3mm, the two-stage grinding magnetic separation process is adopted. If the coarse grinding can separate the qualified tailings, the stage grinding magnetic separation process is adopted. If a certain amount of surrounding gangue minerals are produced in the crushed product at the time of mining, a certain amount of monomeric gangue minerals are produced, and then pre-selected by a dry magnetic separator before grinding. For some ore, in order to obtain high-grade iron concentrate with iron grade of 66% to 68%, it can be treated by fine sieve, magnetic separation column and reverse flotation. At present, there is no reasonable utilization of iron silicate. Although the application of the beneficiation method can be recycled, it will greatly reduce the grade of iron concentrate, which is not economically reasonable. Generally speaking, the charge contains a certain amount of iron silicate, which will not affect the antegrade process of the large and medium-sized blast furnace, and the iron in the iron silicate will not be lost from the slag, but in the smelting of the small blast furnace, due to the iron silicate During the smelting process, it is an endothermic reaction, and the melting point is low, which will lower the furnace temperature and affect the smelting process, and the iron content lost with the slag will increase. Third, hematite ore beneficiation method and process Hematite ore is a kind of weak magnetic iron ore. There are many methods of mineral processing, including re-election, flotation, strong magnetic separation, roasting magnetic separation and a combination of several methods. In recent years, a joint process with both parallel and series combinations has been widely used. For example, the lean red iron ore in the Anshan area uses a combined process of re-election, magnetic separation and flotation to obtain a high index of concentrate iron grade of 65% to 67%. (1) Single hematite ore Such ores include hematite ore, ducted ore, limonite ore, limonite or red (mirror iron)-cementite ore in sedimentary metamorphism, sedimentary, hydrothermal and weathered deposits. There are two common methods of mineral processing. 1. Magnetization roasting magnetic separation Roasting magnetic separation is one of the effective methods for selecting fine particles to fine particles (<0.02 mm) hematite. When the mineral composition is relatively complicated, and other beneficiation methods are difficult to obtain good sorting indicators, magnetization roasting magnetic separation is often used. The shaft furnace reduction roasting process of 75~20mm lump ore is mature, and has long-term production practice experience. The practice of magnetizing roasting in 20~0mm rotary kiln is less. For the fine magnetic separation, re-election, flotation and other methods commonly used in powder ore and their joint processes are selected. 2. Re-election, flotation, strong magnetic separation and joint process Flotation is one of the common methods for selecting fine particles to micro-hematite ore. It is divided into positive flotation and reverse flotation, and all have practical production experience. Re-election and strong magnetic separation are mainly used to select coarse (20 ~ 2mm) and medium hematite. Due to the great development of technology in recent years, it has been widely used to select fine-grained hematite. The re-election of massive (>20mm) and coarse ore is usually carried out by heavy medium or jigging method. For the re-election of medium and fine ore, the membrane separation method such as spiral concentrator, shaker and centrifugal concentrator is used. The strong magnetic separation of coarse and medium ore is commonly used in induction roller type strong magnetic separator. The strong magnetic separation of fine ore is commonly used in wet induction medium vertical ring, flat ring strong magnetic separator and pulsating high gradient magnetic separator. At present, due to the low grade of strong magnetic concentrate of fine ore and the low reprocessing capacity, it is often composed of a combination of strong magnetic separation-re-election and strong magnetic separation-flotation, and a large number of qualified tailings are discarded by strong magnetic separation. Re-election and flotation further process the strong magnetic separation concentrate to further increase the iron grade. The application of various beneficiation methods and their combined processes varies with the type of ore. Sedimentary metamorphic hematite iron minerals are mainly hematite, gangue minerals are mainly quartz, sedimentary metamorphic mirror iron-siderite ore, iron minerals are mainly specular iron or siderite, gangue minerals There are quartz, jasper, barite and dolomite. These sedimentary metamorphic iron ores are in fine-grained inlays and almost all of the beneficiation methods are used in production. Sedimentary braided hematite ore-ironite ore, iron minerals are mainly hematite and siderite, gangue minerals are chlorite, quartz, and some calcite ; iron minerals It is often a fine-grained inlaid fabric, and it is closely symbiotic with the gangue minerals in a scorpion-like structure, which is difficult to dissociate. Because it is underground mining, it is easy to be depleted by surrounding rock. This type of ore is more difficult to choose. If it is rich or self-fluxing ore, the gangue minerals are removed by heavy medium, jigging or dry magnetic separation to obtain a block of finished iron ore. If it is a rich ore-like ore, it is usually used for roasting magnetic separation, sometimes pre-selection to remove block-shaped gangue minerals before roasting magnetic separation; as for leaner ore particles, even if roasting magnetic separation is used, the concentrate grade is difficult to reach. More than 50%, so it is often used after the removal of surrounding rock and other high-grade concentrates or the use of direct reduction and other methods. Aluminum ore containing high silica to alumina ratio should be noted that the iron ore, self-fluxing or alkaline ore concentrate should be kept autolysis. Hydrothermal quartz hematite ore and hematite-limonite ore are often unevenly embedded, and a combined process of re-election, strong magnetic separation, and flotation is often used. Elective selection of weak magnetic iron ore, with high efficiency, large size range, no magnetization roasting before ore sorting, no consumption of chemicals in the sorting process, no need for water, and thus no need for concentrated filtration dewatering equipment . The experimental research shows that the small cylinder electric separator is used to treat 0.096-0.06mm hematite. When the original ore grade is 32.17%, the yield can be 44.20%, the iron grade is 65.08%, the silica is 4.60%, and the recovery rate is 89.40%. Iron concentrate. For Hainan mirror iron ore, when the ore size is >0.15mm, the ore grade is 29.67%, the yield is 48.13%, the iron grade is 60.49%, the silica is 9.18%, and the recovery is 98.10%. Electrification can also be applied to the recovery of iron tailings. When selecting the material in the Qidashan tailings reservoir (-0.11mm), the FGD composite high-pressure electric separator can select the concentrate yield from the ore of 33.70% of the iron grade. 40.39%, concentrate concentrate 66.06%, recovery rate of 79.17% iron concentrate. Before the electrification, the ore needs to be dried and heated, and strictly classified. When the minerals in the ore are similar in conductivity, it is difficult to sort and the surface should be scrubbed and cleaned. The granulated iron method is used to treat high-silicon lean iron ore that is difficult to obtain good mineral processing indicators by mechanical beneficiation. Of the Southwest Hunan disseminated hematite particles, carbon resistance furnace using the test chamber, the temperature of 1300 ~ 1350 ℃, add the reducing agent available anthracite particles of iron, TFe96.21%, S0.261%, P0.81 % , C2.54%, TFe recovery rate of 93.7%. (B) Multi-metal-containing hematite It is mainly hydrothermal deposition type and phosphorus-containing or sulfide-containing ore hematite and chabazite. Such ores generally recover iron minerals by re-election, flotation, strong magnetic separation or other combined processes, and recover phosphorus or sulfide by flotation. Hydrothermal apatite-containing hematite and containing copper, iron ore can be treated with sulfur Ling flotation. Sedimentary phosphorus-containing hematite ore, phosphorus is in the state of colloidal phosphate. Although it can be separated from iron mineral by flotation, it is often difficult to integrate phosphorus concentrate, which reduces the iron recovery rate. For the development of sedimentary phosphorus-containing hafnite hematite ore, re-election or magnetic separation may be considered for coarse pre-selection of ore, removing large-scale surrounding rock and stone, restoring the geological grade of the ore, and then sintering it into the furnace for smelting. Production of high-phosphorus pig iron, and then converter steel, while producing steel slag phosphate fertilizer. The method has the advantages that the beneficiation method is simple, avoids the complicated process of fine grinding and deep selection of phosphorus, silicon and aluminum, and maintains the self-fluxing of the ore, so that the phosphorus is fully utilized. (3) Magnet-red (Ring) iron ore mixed ore beneficiation method and process 1. Single magnet - Chi (Ring) iron ore It is mainly composed of metamorphic magnetite ore and magnetite. The iron minerals in the ore are magnetite and hematite or rhomboid ore, which are mostly fine-grained; the gangue minerals are mainly quartz, and some contain more iron silicate. The proportion of magnetite in the ore varies, often from the surface of the deposit to the depth of the deposit. There are two kinds of ore dressing methods commonly used in this type of ore: one is weak magnetic separation and re-election, flotation, strong magnetic separation combined process, magnetite recovery by weak magnetic separation, weak recovery by re-election, flotation or strong magnetic separation The combined process of magnetic iron minerals has been used more in recent years. This is because weak magnetic separation of magnetite is far more economical than other methods of beneficiation. At the same time, most mines will gradually change from the original treated magnet-hematite to single magnet ore with the extension of service life. The combined processes that have been used are: weak magnetic separation - flotation, flotation - weak magnetic separation, weak magnetic separation - reselection, weak magnetic separation - strong magnetic separation and weak magnetic separation - strong magnetic separation - reselection - floating Elective. In recent years, flotation-weak magnetic separation, weak magnetic separation-strong magnetic separation, weak magnetic separation-strong magnetic separation-reselection or weak magnetic separation-strong magnetic separation-flotation, weak magnetic separation-strong magnetic separation-reselection - Joint processes such as flotation are more popular. The second is the combined process of magnetization roasting magnetic separation or other beneficiation methods. The magnetization roasting magnetic separation is similar to the magnetization roasting magnetic separation process of a single hematite ore, but in the parallel flow with other beneficiation methods, the powder ore is used. Weak magnetic separation is treated in combination with other mineral processing methods. In addition, there is a series process of roasting magnetic separation and other beneficiation methods, that is, roasting magnetic separation concentrate and flotation or re-election to further improve the concentrate grade. The magnet-embedded magnet-hematite ore is difficult to obtain good results by general ore dressing methods. Selective flocculation de-sludge, flocculation flotation, flocculation strong magnetic separation and flocculation re-election should be used. 2, containing multi-metal magnets - red (magnetic) iron ore Among these ores, there are skarn-type sulfide-containing mixed iron ore and hydrothermal type mixed iron ore containing phosphorus, sulfur or rare earth. The ore dressing method for this type of ore is the most complex of iron ore. Generally, the combined process of weak magnetic separation and other beneficiation methods is used, that is, magnetite is recovered by weak magnetic separation; weak magnetic red (red) iron minerals are recovered by re-election, flotation or strong magnetic separation; Component. The process includes: weak magnetic separation - flotation - strong magnetic separation, weak magnetic separation - strong magnetic separation - flotation and weak magnetic separation - reselection - flotation. For rare earth-containing mixed iron ore, if the iron mineral is mainly composed of a large amount of hematite, the reduction roasting magnetic separation-flotation process is also adopted, that is, the hematite mineral is recovered by reduction roasting, and the rare earth mineral is recovered by flotation. . The flotation of rare earth minerals after reduction roasting is beneficial to improve the selection index. In addition, the flotation-selective flocculation process also achieves high targets. Fourth, brown iron ore beneficiation method and process The limonite is 2Fe2O3·3H2O, which is distributed in the provinces of Guangdong and Jiangxi. Because it is rich in crystal water, it is difficult to achieve 60% of the iron grade by physical beneficiation. However, after calcination, it can be large due to large burning loss. Increase the grade of iron concentrate. In addition, since limonite is easily muddy during the grinding process, it is difficult to obtain a high metal recovery rate. The iron pit limonite deposit is a pyrite skarn type iron cap limonite deposit. The ore industry types are skarn type limonite and high silicon type limonite. The former accounts for 66%, the ore is composed of limonite, hematite and quartz, and the latter consists of limonite, goethite and hematite. The beneficiation method adopts a combined process of magnetization roasting-weak magnetic separation, re-election, strong magnetic separation, flotation, selective flocculation flotation, strong magnetic separation-positive flotation, strong magnetic separation, strong magnetic separation-reverse flotation process. Make a selection. Since its completion and commissioning, Tiekeng Concentrator has been conducting experimental research and production practices for various beneficiation methods and various beneficiation processes, such as re-election, reverse flotation, positive flotation, and strong magnetic separation. The flotation process obtained 35.25% of the original ore grade, 50.52% of the concentrate grade, and the recovery rate was 76.23%. The production practice over the years has shown that the strong magnetic separation-positive flotation combined process selection index is better and the economic benefits are significant. In recent years, the Maanshan Mine Research Institute has developed a strong magnetic separation-cation reverse flotation process. The results of the re-election test show that when the original ore grade is 37.09%, the yield can be 38.26%, the iron grade is 56.73%, and the iron recovery rate is 58.52%. Concentrates meet the quality requirements of smelting for iron concentrates. The process was completed and put into production at the end of 2005. The industrial production practice for half a year shows that the process of using strong magnetic separation-reverse flotation combined mineral processing technology is reasonable, the technology is reliable, the process is stable, and the adaptability is strong. 5. Spinning ore beneficiation method and process The theoretical grade of siderite is only 48.2%, and it is often symbiotic with calcium, magnesium and manganese . Therefore, the physical ore dressing method is difficult to make the iron concentrate grade more than 45%, but after calcination Burning and reducing can greatly improve the grade of iron concentrate. Due to the characteristics of siderite, it is a promising iron ore resource. First, it can improve the iron grade after roasting. If the iron grade is 35%, after roasting at 600°~700°C, the iron grade can be reached. 50%. Second, after the roasting, the siderite is converted into magnetite, which is easy to magnetically select. Thirdly, the siderite has better reducing property. After roasting, CO2 escapes from the ore, which increases the voids in the ore, thereby increasing the contact area with the reducing gas and facilitating smelting. The siderite beneficiation methods include re-election, strong magnetic separation, strong magnetic separation-flotation, magnetization roasting-weak magnetic separation. In recent years, the Changsha Institute of Mining and Metallurgy and other units have been enriched with iron carbonate ore, such as the strong magnetic separation concentrate of Daye Iron Mine, the strong magnetic selected ore of the wine steel selection plant, and the Daxigou siderite, using rotary kiln roasting technology, iron fine The grade of minerals can be increased to 50% to 60%. The Maanshan Mine Research Institute of Sinosteel Group has done a lot of experimental research on the recovery of iron carbonate in the tailings of Taikou Iron Mine, because the iron carbonate is mainly composed of iron and magnesium carbonates. It is recommended to adopt the screening-strong magnetic separation-flotation combined process. The final iron concentrate grade is more than 35% (the iron grade is more than 51% after roasting), the SiO2 content is reduced to below 4%, and the quaternary alkalinity is above 3 It is not only an iron raw material, but also has the properties of iron-making flux. The mixed smelting with acid iron concentrate can greatly improve the metallurgical performance, and the annual economic benefit is considerable. Waterproof Fishing Box,Waterproof Tackle Box,Waterproof Fishing Tackle Box,Waterproof Bait Fishing Box Cixi Jinfeng Plastics Co.,Ltd , https://www.jftoolset.com