Implement the "blast furnace concentrate", energy conservation, it is the mainstream of industrial development of iron and steel in the 21st century. To meet this trend, increase ironmaking technical and economic indicators, Baotou Iron and Steel Company in the "Eleventh Five-Year Plan" put forward higher requirements for beneficiation plant, requires concentrator oxide ore grade of iron concentrate reached 68%. To this end, it is very important to find a reasonable sorting method and process to achieve a 68% grade of oxidized ore concentrate, which is an urgent problem to be solved. Based on the comprehensive analysis and research of the current process, the project firstly conducts process mineralogy research on oxidized ore weak magnetic reversal flotation concentrate and strong magnetic separation concentrate, and then carries out different sorting methods and different sorting processes. The combined experimental study finally determines the use of electromagnetic spiral column-fine sieve-re-grinding-weak magnetic separation process for magnetically strong weak magnetic reversal flotation concentrate, and fine sieve-reverse and positive floating for magnetic weak magnetic precision Selection process. The test index is advanced, the grade of oxidized ore iron concentrate reaches 68.18%, the recovery rate is 68.73%, and after the new process, the content of impurities such as K 2 O+Na 2 O and SiO 2 in the iron concentrate is obviously reduced, effectively improving. iron ore quality, improve the performance of gold mining and metallurgy Bayan Obo, in order to achieve fine material policy, improve the utilization coefficient of blast furnace smelting to obtain greater economic benefits provided guarantee for raw materials. I. Oxidized ore production status and raw material properties The oxidized ore of Bayan Obo Mine is world-famous because of its low iron grade, complex mineral composition, close symbiotic relationship, fine and uneven grain size, small difference in useful minerals and gangue minerals, and many types of ore. Difficult to mine. The current production process of oxidized ore is a weak magnetic separation-strong magnetic separation-reverse and positive flotation process. At present, because the weak magnetic iron minerals and iron-containing silicate minerals are not effectively separated, the grade of oxidized ore concentrate is about 65%, which is far from the level required by the company (the grade of oxidized ore concentrate is 68%). . The current production process is shown in Figure 1. Figure 1 Oxidized ore weak magnetic separation - strong magnetic separation - reverse, positive flotation process During the test, oxidized ore TFe 29. 4%, FeO 8.8%, K 2 O+Na 2 O 0.78%, SiO 2 11.54%, F 8.29%, iron minerals dominated by magnetite-hematite minerals (accounting for 39.89%), the magnetic iron content is relatively high, accounting for 71.43%. The gangue minerals are mainly fluorite , amphibole, pyroxene, dolomite, calcite, etc., which is the oxidized ore used in the normal production of the ore dressing plant. The results of multi-element chemical analysis, iron phase analysis and mineral composition analysis of oxidized ore are shown in Table 1, Table 2 and Table 3, respectively. Table 1 Results of chemical analysis of multi-element oxidized ore Table 2 Analysis results of oxidized iron phase Table 3 Analysis results of oxidized mineral composition analysis % Second, the content of the experimental research and the determination of the test process (1) Study on the mineralogy of weak magnetic reversal flotation concentrate and strong magnetic concentrate in the current oxidation ore process, and determine the mineral composition, iron phase and monomer dissociation degree of the two products. (2) The experimental study on the weak magnetic reversal flotation concentrate using electromagnetic spiral column-fine sieve-re-grinding-weak magnetic separation process. (3) Experimental research on fine magnetic separation concentrate using fine screening process. (4) Feasibility test study on the flotation of products under the sieve. It is finally determined that the oxidized ore weak magnetic reversal flotation concentrate adopts electromagnetic spiral column-fine sieve-re-grinding-weak magnetic separation, strong magnetic precision adopts fine sieve-reverse and positive floating new process, and the test flow is shown in Fig. 2. Figure 2 Oxidized ore adopts new process test procedure Third, the test results and discussion The oxidized ore weak magnetic reversal flotation concentrate adopts spiral column-fine sieve-re-grinding-weak magnetic separation process and strong magnetic precision adopts fine sieve-reverse and positive floating new process test number quality process as shown in Fig. 3, test index and original The process indicators are compared in Table 4. The results of multi-element chemical analysis and mineral composition analysis of concentrates are shown in Tables 5 and 6, respectively. Figure 3 Oxidized ore uses a new process to test the mass quality process Table 4 Comparison of new process and original process index of oxidized ore Table 5 Multi-element chemical analysis results of concentrates % Table 6 Quantitative analysis results of concentrate mineral composition % It can be seen from Table 4 that under the condition of 29.36% of raw ore Tef and 8.33% of FeO, compared with the original process, the new process of oxidized ore is adopted, and the grade of iron concentrate is increased from 64.39% to 68.18%, which is 3.79 percentage points higher. The rate dropped from 72.33% to 68.73%, a decrease of 3.6 percentage points. The final concentrate consists of sieved products, finely ground weak magnetic concentrate and positive flotation concentrate. It can be obtained from multi-element analysis and quantitative analysis of mineral composition. The new iron ore concentrate will not only improve the iron grade significantly. 68.18%, and the content of impurities such as K 2 O+Na 2 O, SiO 2 , F, P, etc. are obviously reduced, the silicate content in iron concentrate is reduced, and the quality of iron concentrate is effectively improved, which is “fine material†The realization of the policy laid the foundation. Fourth, the rational analysis of the test process (1) Oxidized ore weak magnetic fine reverse flotation concentrate electromagnetic spiral column-fine sieve-re-grinding-weak magnetic separation process 1. For the oxidized ore weak magnetic fine reverse flotation concentrate (about 66% TFe), the electromagnetic-fine sieve-re-grinding-weak magnetic separation combined process is adopted, and the continuous magnetic polymerization-dispersion of the material in the electromagnetic spiral column is realized. -Selected several times to improve the grade of weak magnetic reversal flotation concentrate, and then use MVS high frequency vibrating mesh screen to further improve the monomer dissociation degree of the undersize product, and the iron grade is greater than 69. % qualified concentrate. 2. For intermediate products with high content of sieve and spiral column overflowing with high content and relatively coarse grain size, fine grinding and re-election process is adopted to determine the appropriate grinding fineness - 200 mesh accounts for 92.50%, so that iron minerals are fully dissociated And then obtain a weak magnetic separation concentrate with a grade greater than 68% by weak magnetic separation. The undersize product and the weak magnetic separation concentrate are combined into a final iron concentrate with an iron grade of over 68%. (2) Fine magnetic fine-grained fine-reverse and positive flotation process 1. The fine magnetic separation concentrate is applied to the strong magnetic separation concentrate with high content of iron-containing silicate minerals. By selecting reasonable meshing holes, the monomer dissociation degree of the under-screen products can be effectively improved, thereby improving the iron concentrate grade; About 20% of the gangue minerals are thrown away, improving the conditions of reverse flotation and reducing the cost of flotation. 2, for the undersize product is first carried out in alkaline medium using reverse flotation, fluorite, carbonate, or phosphate and other minerals removed, followed by flotation (1 roughing in an acidic medium, 2 Selected), further separating the iron minerals from the iron-containing silicate minerals, so that the grade of the reverse flotation-positive flotation concentrate reaches about 60.50% of TFe. Fifth, the implementation effect The success of this test has made the oxidized ore beneficiation technical index of Baotou Steel Concentrator reach the advanced level of domestic oxidized ore beneficiation, and the success of the project has great economic and social benefits for smelting. The improvement of the quality of iron concentrates has improved the metallurgical properties of iron raw materials, and made outstanding contributions to reducing ironmaking costs, increasing the utilization coefficient of blast furnaces, and promoting the development of smelting systems. Conclusion (I) During the test period, the oxidized ore TDE was 29.4%, FeO 8.8%, K 2 O+Na 2 O 0.78%, SiO 2 11.54%, F 8.29%, and iron minerals were mainly magnetite-hematite minerals. It accounts for 39.89%, and the magnetic iron content accounts for 71.43%. The gangue minerals are mainly fluorite, amphibole, pyroxene, dolomite and calcite. The ore is an oxidized ore used in the normal production of a concentrator. (2) Oxidized ore adopts electromagnetic spiral column-fine sieve-re-grinding-weak magnetic separation and strong magnetic fine screening-reverse and positive floating new technology to achieve the purpose of improving quality and reducing impurities. After adopting the new process, the iron concentrate grade increased from 64.39% to 68.18%, increased by 3.79 percentage points, and K 2 O+Na 2 O in iron concentrate, under the condition of oxidized iron grade TFe 29.56% and FeO 8.33%. The main harmful impurities such as SiO 2 , F, P are obviously reduced, providing high-quality raw materials for smelting, laying a foundation for improving the utilization coefficient of blast furnace. (3) The process technology route is reasonable and feasible, with advanced indicators, strong industrial operation and easy industrial implementation. (IV) The success of the project has made the oxidized ore beneficiation technical index of Baotou Steel Concentrator reach the advanced level of domestic oxidized ore beneficiation, which provides a technical basis for the technical transformation of oxidized ore. brass Press Fittings according to vigea and connex quality,approved kitemark and DVGW,Brass Press Fittings,brass press fittings,press Brass Fittings,pipe press fittings, V type brass press fittings,M type brass press fittings,M type brass press fittings Brass M type adapter press fitting Lead Free Brass Press Fittings 1/2"-2" Brass Press Fittings,brass press fittings,press brass fittings,pipe press fittings, V type brass press fittings,M type brass press fittings Taizhou Runde Company , https://www.nerausmotor.com