Foreword Hematite iron ore resources in our possession a sizeable proportion of magnetite compared to hematite, hematite most disseminated fine grain size, containing a large quantity of mud, dressing difficult. Therefore, since the "Sixth Five-Year Plan", China has used hematite as a national scientific research project and has achieved fruitful results. Some large hematite mines have accumulated a lot of experience in mineral processing technology, equipment and pharmaceuticals, and have achieved good selection indicators. Due to the shortcomings of most process processes, high equipment investment and high beneficiation costs, these processes are difficult to adopt for some small and medium-sized hematite mines, especially small and medium-sized mines where hematite and magnetite are mixed. There are few large-scale hematite mines in China, and there are many small and medium-sized hematite mines. Therefore, it is especially important to study the beneficiation process suitable for small and medium-sized hematite mines. This paper conducts a beneficiation test on a small hematite beneficiation with a short service life, and provides an economical and rational beneficiation process for the small hematite mine. This study can also serve as a reference for other small hematite concentrators. First, the nature of the ore (1) The main chemical components of the ore The mine belongs to the Anshan-type sedimentary metamorphic oxidized hematite or magnetite deposit. The main chemical composition analysis of the ore is shown in Table 1. (2) Mineral composition Most of the magnetite is replaced by different degrees of hematite, forming false and semi-artificial hematite, a small amount of limonite, and the degree of oxidation is deep. The iron mineral is in the form of granular single crystal or aggregate in the gangue. It is distributed in strips with gangue minerals (mainly quartz , a small amount of chlorite, etc.). Metallic mineral mainly in the illusion of hematite, magnetite and semi martite main gangue minerals are quartz, chlorite-based. Its mineral composition is shown in Table 2. (3) Embedding characteristics of iron minerals 1. Magnetite (Fe 3 O 4 ) The magnetite is semi-self-shaped granular single crystal or aggregates impregnated in the gangue or distributed in a strip shape with the gangue. Most of the magnetite is replaced by semi-artificial hematite along the edges and fissures. The semi-artificial hematite is difficult to separate from the magnetite and thus ferromagnetic. The magnetite is embedded in coarse, medium and fine particles, and the magnetite inlay has a particle size of 0.02 to 0.6 mm. 2. Hematite (Fe 2 0 3 ) The semi-artificial hematite is grid-like, irregularly granular, veined along the edge of the magnetite, and fissures are replaced, completely replaced by hematite (magnetite artifact) or trace magnetite. It is assumed that hematite does not exhibit ferromagnetism and has strong electromagnetic properties. The semi-artificial hematite particle size is 0.015-1.6 mm. The pseudo-hematite particle size is 0.01 to 1 mm. 3. Limonite (Fe 2 0 3 ·nH 2 0) The limonite is veined, irregularly granulated, honeycombed, and star-shaped embedded in the gangue. The limonite has a particle size of 0.005 to 0.6 mm. Second, the beneficiation test (1) Magnetic separation-re-election (re-election using a single shaker device) joint process plan test Since the ore is a mixed ore of hematite and magnetite, the ore is first magnetically recovered to recover magnetite, and then the tailings are magnetically selected. It can be seen from the test results in Table 3 that the combined process of magnetic separation and re-election (reselection using a single shaker device) can obtain a yield of 38.43%, an iron grade of 64.42%, and an iron recovery rate of 70. 53% of total iron concentrate. (2) Magnetic separation-re-election (re-selection of spiral chute for rough selection, shaker for selection) joint process test Since the shaker is used as the sorting equipment for hematite in the magnetic-heavy joint process, the number of shakers is large, the floor space is large, and the investment is relatively large. Therefore, the magnetic separation tailings are treated by the spiral chute with relatively large processing capacity. Pre-tailing, coarse concentrates are selected with a shaker to reduce the number of shakers. Therefore, the magnetic separation tailings were tested. The test procedure is shown in Figure 2. The test results are shown in Table 4. It can be seen from the test results in Table 4 that when the iron ore is treated by the magnetic one-weight combined process, the re-election is pre-tailed using a spiral chute, and the spiral chute concentrate is selected by a shaker to obtain an iron grade of 65.56%, iron recovery. The high-quality iron concentrate with a rate of 63.11%, plus the recovery rate of iron in the shaker, the total iron recovery is 69.78%, and the iron concentrate grade is 63.41%. (III) Flotation-magnetic separation joint process plan test After detailed grinding fineness test, collector type test, sodium carbonate dosage test, inhibitor type test, inhibitor dosage test, and collector dosage test, the best test procedure for flotation was finally determined. In order to recover the iron lost in the flotation tailings, a weak magnetic separation test was carried out on the flotation tailings. The test procedure is shown in Figure 3, and the test results are shown in Table 5. It can be seen from the test results in Table 5 that the total iron concentrate with a yield of 40.27%, a grade of 62.37% and a recovery of 72.36% can be obtained by the flotation-magnetic separation process. Fourth, the results of the discussion It can be seen from the above test results that the magnetic separation-re-election (reselection using a single shaker device) combined process scheme can achieve a yield of 17.09%, iron grade 69.40%, iron recovery. The rate of 33.79% of the magnetic separation iron concentrate, magnetic separation tailings with a shaker can obtain a yield of 21.34%, iron grade 60.43%, iron recovery rate of 36.74% re-election concentrate, total The iron concentrate has an iron grade of 64.42% and an iron recovery of 70.43%. Although the recovery rate of the iron by the shaker is higher, the use of the shaker to select the tailings for magnetic separation requires a large number of shakers, a large area, and a relatively large investment. In order to save investment, the magnetic separation tailings are treated with a large amount of spiral chute, and the tailings are pre-thrown. The spiral chute concentrate is selected by a shaker. Although the iron recovery rate is lower, the quality of the iron concentrate is higher. The important thing is that the process is simple, adaptable, saves investment, and is easy to operate. It is conducive to speeding up production for small mines. The flotation-magnetic separation combined process scheme is used to treat the iron ore. Although the iron recovery rate is high, the iron concentrate grade is low, and a large amount of flotation reagent is consumed during the flotation treatment, so that the production cost is increased. For small hematite concentrators, it is not conducive to maintenance and management. Therefore, it is appropriate to use a magnetic separation-re-election combined process (re-election using a spiral chute and a shaker combination) for the small hematite concentrator. The process is simple, the technology and economy are reasonable, and the adaptability to the ore properties is relatively strong. V. Conclusion (1) The hematite is treated by a magnetic one-weight combined process, and the spiral chute is pre-pitched. When the spiral chute concentrate is selected by a shaker, the iron grade can be 65.56%, and the iron recovery rate is 63.11%. The high-quality iron concentrate, together with the iron in the shaker, can obtain a total concentrate with an iron concentrate grade of 63.41% and an iron recovery of 69.78%. (2) The process is simple, adaptable, saves investment, and is simple and easy. For a small hematite mine with a short service life, it is conducive to speeding up production and quickly recovering costs. This process can also serve as a reference for other small hematite concentrators. Wire Butt Welding Machine,Energy-Saving Welding Machine,Automati Butt Welding Machine,Rim Welding Machine Jiangyin Keyu Electric Co., Ltd , https://www.wirebuttweldingmachines.com