Method for realizing beneficiation and enrichment of uranium-molybdenum ore based on superconducting magnetic separation

Abstract

The invention discloses a method for realizing beneficiation and enrichment of uranium-molybdenum ore based on superconducting magnetic separation, and belongs to the technical field of beneficiation. According to the method, on the basis of grading the uranium-molybdenum ore, separation is carried out according to the property difference of minerals of different size fractions, a separation medium filling scheme of superconducting magnetic separation is optimized, the serious gangue mineral mechanical inclusion phenomenon in a superconducting separation field space can be eliminated, the indexes of uranium-molybdenum ore superconducting separation products are greatly improved, and the method is suitable for industrial production. The molybdenum grade of a concentrate product after separation is obviously improved, efficient separation of molybdenum-containing useful minerals and gangue minerals is achieved, and the problems that in the separation process of existing high-clay low-grade uranium-molybdenum ore through a superconducting magnetic separator, the gangue minerals are seriously mechanically mixed in the separation cavity space, the separation efficiency of the superconducting magnetic separator is reduced, and the separation efficiency of the superconducting magnetic separator is reduced are well solved. And efficient separation of the molybdenum-containing minerals cannot be achieved.

Description

Technical Field

[0001] The present invention relates to a method for beneficiation and enrichment of uranium-molybdenum ore, and particularly to a method for beneficiation and enrichment of high-clay and low-grade uranium-molybdenum ore based on superconducting magnetic separation, belonging to the technical field of mineral separation. Background Art

[0002] Molybdenum mainly exists in two forms, oxidized state and sulfide state, in the earth's crust, and coexists with a variety of beneficial components. For example, molybdenum-containing minerals coexisting with metals such as tungsten, copper, and uranium are common. At present, for sulfide molybdenum-containing minerals, the separation technology of molybdenite is relatively mature, but the efficient enrichment of oxidized and amorphous molybdenum-containing minerals with huge resources has always been a hot and difficult research issue.

[0003] A certain low-grade uranium-molybdenum deposit is a typical volcanic rock type uranium-molybdenum polymetallic deposit. The ore contains complex mineral species, high oxidation degree, and high gangue content. Among them, the content of gangue minerals such as quartz and clay exceeds 85%. The high clay and high gangue result in extremely poor separation indexes of this ore. Traditional gravity separation, magnetic separation, and flotation processes cannot achieve selective enrichment, seriously restricting the efficient development and utilization of this ore. Superconducting magnetic separators have higher magnetic field strength and magnetic field gradient compared with traditional magnetic separators, and can achieve efficient recovery of molybdenum-containing particles with weak magnetism ("Analysis of the reasons for the low magnetic separation recovery rate of fine-grained ilmenite", Li Lixia, et al., China Mining Magazine, 2018, 27(11): 138-144). However, currently, domestic existing superconducting magnetic separators, in order to maximize the ability of the equipment to recover fine and weakly magnetic particles, have been committed to mechanically increasing the probability of particles in the separation space contacting the separation medium by continuously increasing the filling density of superconducting separation media such as poly-magnetic steel nets and poly-magnetic bristles in the separation chamber, so that particles with weak magnetism can be effectively captured and recovered by the medium. For example, in the field of using superconducting magnetic separation for iron removal and whiteness improvement of kaolin, and even in the entire non-metallic ore separation field when using superconducting magnetic separation for separation and impurity removal, this medium design idea is widely adopted. It is precisely based on the feasibility of this idea in the non-metallic ore separation field that when studying the superconducting separation of metal ores in China, in order to achieve a more sufficient separation effect, the same medium design scheme is generally adopted. However, this scheme has always had problems. The common problem is that the grade of the magnetic concentrate product separated is low and difficult to improve. For example, ("Separation of Copper-Molybdenum Flotation Concentrate by Superconducting High-Gradient Magnetic Separation", Wang, Z., et al, Minerals 2022, 12,1191.) It is reported that a copper-molybdenum mixed ore is concentrated by superconducting magnetic separation. The original ore has a copper grade of 18.52%. After separation, the copper recovery rate of the concentrate reaches 81.59%, but the copper grade is only 19.64%, and the separation efficiency is low. Fundamentally speaking, when the current design concept of superconducting magnetic separation medium is applied to the separation of metal ores, due to the large distribution density of the separation medium and the single form of the medium, the force forms of particles with different particle sizes between the media are too different, resulting in the accumulation of gangue minerals and mechanical entrainment of gangue in the separation space. Eventually, a large amount of gangue minerals are mixed into the concentrate product, forcing the grade of the concentrate to be lowered, thus greatly reducing the separation efficiency of metal ores. This is also the main reason why there has been no progress and stagnation in the field of superconducting separation of metal ores in China.

[0004] Targeted design is carried out on the separation medium of the superconducting magnetic separator to optimize the separation space directionally, reduce the mechanical entrainment phenomenon in the separation space, improve the separation efficiency, realize the efficient separation and enrichment of molybdenum-containing minerals with weak magnetism, provide separation equipment support for the efficient separation of this ore, improve the utilization rate of molybdenum resources, and have great significance. Summary of the Invention

[0005] Aiming at the problem that during the enrichment of high-clay and low-grade uranium-molybdenum ore by a superconducting magnetic separator, the mechanical entrainment of gangue minerals between the separation media is serious, resulting in a reduction in the separation efficiency of the equipment and the inability to achieve efficient separation of molybdenum-containing minerals. The purpose of the present invention is to provide a method for uranium-molybdenum ore beneficiation and enrichment based on superconducting magnetic separation. This method aims at the mineral composition characteristics of low-grade uranium-molybdenum ore, first classifies the ore, and then based on the property differences of minerals in different particle size grades, selects different medium filling schemes for targeted separation respectively, which can well eliminate the serious mechanical entrainment phenomenon of gangue minerals in the superconducting separation field space, greatly improve the indexes of the superconducting separation products of uranium-molybdenum ore, significantly increase the molybdenum grade of the concentrate product after separation, and realize the efficient separation of molybdenum-containing useful minerals and gangue minerals.

[0006] In order to achieve the above technical purpose, the present invention provides a method for uranium-molybdenum ore beneficiation and enrichment based on superconducting magnetic separation, which includes the following steps: 1) Crush and screen and classify the original uranium-molybdenum ore. The particles in the range of -0.5mm to +0.075mm are the coarse particle grade, and the particles in the range of -0.075mm are the fine particle grade; 2) After adjusting the pulp density of the coarse fraction, feed it into Superconducting Magnetic Separator I for Magnetic Separation I to obtain Concentrate I. The sorting medium in the superconducting magnetic separator includes Poly-magnetic Steel Rod I and Poly-magnetic Steel Mesh I, and its filling method is as follows: the upper layer is double-layer poly-magnetic steel rods, the middle layer is single-layer poly-magnetic steel mesh, and the lower layer is double-layer poly-magnetic steel rods, which are filled by stacking in sequence. Among them, the wire pole angle between the two layers of poly-magnetic steel rods in the upper layer is maintained at 60° - 90°, and the surface distance of the wire pole between the middle layer and the upper and lower layers is 1.5 - 2 mm; the filling rate of the poly-magnetic steel mesh in the middle layer is 16% - 20%, and the wire pole angle between the two layers of poly-magnetic steel rods in the lower layer is maintained at 60° - 90°. 3) After adjusting the pulp density of the fine fraction, feed it into Superconducting Magnetic Separator II for Magnetic Separation II to obtain Concentrate II. The sorting medium in the superconducting magnetic separator includes Poly-magnetic Steel Rod II and Poly-magnetic Steel Mesh II, and its filling method is as follows: the upper layer is double-layer poly-magnetic steel rods, the middle layer is single-layer poly-magnetic steel mesh, and the lower layer is double-layer poly-magnetic steel rods, which are filled by stacking in sequence. Among them, the wire pole angle between the two layers of poly-magnetic steel rods in the upper layer is maintained at 60° - 90°, and the surface distance of the wire pole between the middle layer and the upper and lower layers is 1.0 - 1.5 mm; the filling rate of the poly-magnetic steel mesh in the middle layer is 11% - 15%, and the wire pole angle between the two layers of poly-magnetic steel rods in the lower layer is maintained at 60° - 90°.

[0007] The key to the uranium-molybdenum ore beneficiation and enrichment method provided by the present invention lies in: on the basis of classifying the uranium-molybdenum ore, adopting a superconducting magnetic separation method with different sorting media filled for uranium-molybdenum ores of different particle sizes, and by optimizing the sorting medium filling scheme, greatly improving the sorting efficiency of superconducting magnetic separation, and well solving the technical problems such as low sorting efficiency of existing superconducting magnetic separation for uranium-molybdenum ore, too high yield of concentrate products, and serious mechanical entrainment of gangue minerals. More specifically, the -0.5mm minerals are classified, the particles in the range of -0.5mm to +0.075mm are the coarse particle size grade, and the particles within the range of -0.075mm are the fine particle size grade. If the uranium-molybdenum ore is not classified, due to the too wide distribution range of the particle size of the ore to be selected and the too large particle size difference, it is difficult for the sorting medium to capture the target mineral particles with too large particle size differences at the same time. The too large particle size difference of the particles will lead to poor selectivity of the sorting medium and reduced capture ability for the target minerals, thereby affecting the sorting efficiency. After classifying the uranium-molybdenum ore, the coarse and fine particle size grade minerals are separated and sorted, greatly improving the uniformity of the ore particles to be selected and ensuring the sorting efficiency of the magnetic concentrating medium. On the basis of classifying and sorting the uranium-molybdenum ore, a combination filling of a magnetic concentrating rod medium and a magnetic concentrating net medium matching the particle size grade of the material to be selected is adopted, which can specifically regulate the magnetic field gradient and eliminate the phenomena of magnetic blockage, magnetic wrapping, and magnetic entrainment caused by uneven mineral particle size distribution and the use of a single type of sorting medium. On the basis of selecting the combined sorting medium of the magnetic concentrating rod and the magnetic concentrating net, the filling method of the sorting medium is further optimized. By optimizing the surface distance between the wire electrodes of the superposed magnetic concentrating rod medium and the magnetic concentrating net medium, adjusting the filling rate of the magnetic concentrating net medium, and controlling the medium angle, etc., not only the magnetic field force action intensity of the magnetic concentrating medium is improved, the effective capture area of the magnetic concentrating medium is increased, but also the slurry fluidity in the sorting chamber can be improved, the fluid resistance is reduced, the mechanical entrainment of gangue minerals on the magnetic concentrating medium is reduced, and the sorting efficiency of the superconducting magnetic separator is significantly improved.

[0008] As a preferred scheme, the wire electrode spacing of the magnetic concentrating steel rod I is 2.5mm to 3mm, and the wire diameter is 2.5mm to 3mm; the wire electrode spacing of the magnetic concentrating steel net I is 4.5mm to 6mm, and the wire diameter is 1.4mm to 1.8mm. The preferred wire electrode parameters of the magnetic concentrating steel rod I and the magnetic concentrating steel net I match the particle size grade of the coarse particle size grade uranium-molybdenum ore to be selected, and are mainly determined according to the particle size of the uranium-molybdenum ore.

[0009] As a preferred scheme, the coarse particle size is adjusted to a mass concentration of 10% to 15%.

[0010] As a preferred scheme, the slurry feeding rate of the magnetic separation I is 7 to 11 L / min.

[0011] As a preferred solution, the wire electrode spacing of the magnetic concentrating steel rod II is 1.3 mm to 1.5 mm, and the wire diameter is 1.3 mm to 1.5 mm; the wire electrode spacing of the magnetic concentrating steel mesh II is 1.8 mm to 2.6 mm, and the wire diameter is 0.8 mm to 1.0 mm. The wire electrode parameters of the preferred magnetic concentrating steel rod II and magnetic concentrating steel mesh II are matched with the particle size of the selected fine-grained uranium molybdenum ore, and are mainly determined according to the particle size of the uranium molybdenum ore.

[0012] As a preferred solution, the fine-grained pulp is adjusted to a mass concentration of 10% to 15%.

[0013] As a preferred solution, the pulp feeding rate of the magnetic separation II is 7 to 11 L / min.

[0014] The uranium molybdenum ore involved in the present invention is a high-clay and low-grade uranium molybdenum ore, and its main gangue minerals include quartz and feldspar, with a mass fraction of more than 75%; the mass fraction of clay minerals is about 20%, and the mineral types include illite and kaolinite; the content of useful minerals is only about 5%, showing the characteristics of high clay and high gangue minerals.

[0015] A uranium molybdenum ore beneficiation and enrichment method provided by the present invention includes the following specific steps: 1) Mineral classification: The uranium molybdenum ore raw ore is crushed by a jaw crusher to -2 mm and all passes through a sieve. The crushed product is wet-screened and classified using a standard sieve with a sieve hole size of 0.5 mm. The -0.5 mm particle size fraction enters the classification and separation process; in this classification and separation process, the particle size fraction of -0.5 mm to +0.075 mm is defined as the coarse particle size fraction and enters the coarse particle size fraction separation process; the -0.075 mm particle size fraction is the fine particle size fraction and enters the fine particle size fraction separation process; the +0.5 mm particle size fraction is ground, and the ground product all passes through a 0.5 mm standard sieve and enters the same classification and separation process.

[0016] 2) High-efficiency enrichment of coarse-grained ore: For the coarse-grained particles, add clear water to adjust the pulp concentration to 10% to 15%, and feed the evenly stirred pulp into the superconducting magnetic separator at a flow rate of 7 to 11 L / min. Use the coarse particle size fraction separation medium filling scheme to achieve the high-efficiency recovery of weakly magnetic molybdenum-containing mineral aggregates with larger particle sizes. The specific coarse particle size fraction separation medium filling scheme is as follows: the separation medium selects a magnetic concentrating steel rod with a wire electrode spacing of 2.5 mm to 3 mm and a wire diameter of 2.5 mm to 3 mm, and a magnetic concentrating steel mesh with a wire electrode spacing of 4.5 mm to 6 mm and a wire diameter of 1.4 mm to 1.8 mm; the filling scheme is that the number of magnetic concentrating steel rods and magnetic concentrating steel meshes is filled in a cross-over manner at a ratio of 2:1. The wire electrode angles of the upper and lower layers of the mutually superimposed magnetic concentrating steel rods are maintained at 60° to 90°, the surface distance between the wire electrodes of the upper and lower layers of the mutually superimposed magnetic concentrating steel rods and magnetic concentrating steel meshes is maintained at 1.5 to 2 mm, and the filling rate of the magnetic concentrating steel mesh is maintained at 16% to 20%.

[0017] 3) High - efficiency enrichment of fine - grained ore: For fine - grained particles, add clear water to adjust the pulp concentration to 10% - 15%. Feed the evenly stirred pulp into the superconducting magnetic separator at a flow rate of 7 - 11 L / min, and use the filling scheme of fine - grained separation medium to achieve efficient separation of molybdenum - containing minerals with a higher degree of dissociation and gangue minerals. The specific filling scheme of the fine - grained separation medium is as follows: The separation medium selects poly - magnetic steel rods with a wire - pole spacing of 1.3 mm - 1.5 mm and a wire diameter of 1.3 mm - 1.5 mm, and poly - magnetic steel meshes with a wire - pole spacing of 1.8 mm - 2.6 mm and a wire diameter of 0.8 mm - 1.0 mm; the filling scheme is that the poly - magnetic steel rods and poly - magnetic steel meshes are filled in a cross - overlay manner with a quantity ratio of 2:1. Among them, the wire - pole angles of the upper and lower layers of the mutually overlaid poly - magnetic steel rods are maintained at 60° - 90°, the surface distance between the wire - poles of the upper and lower layers of the mutually overlaid poly - magnetic steel rods and poly - magnetic steel meshes is maintained at 1 - 1.5 mm, and the filling rate of the poly - magnetic steel mesh is maintained at 11% - 15%.

[0018] The present invention classifies uranium - molybdenum ore and specifically optimizes the filling ratio, layout method, etc. of the separation medium of the existing superconducting magnetic separator to strengthen the recovery of uranium - molybdenum ore, while reducing the magnetic blockage of the target mineral particles in the separation field, eliminating the phenomena of magnetic wrapping and magnetic inclusion, and realizing the efficient separation of gangue mineral particles and target mineral particles.

[0019] Compared with the prior art, the beneficial technical effects brought by the technical solution of the present invention: 1) Adopting the classification and separation process effectively avoids the phenomenon that the particle size range of the ore to be separated is too wide and the particle size difference is too large. Since it is difficult for the separation medium to capture target mineral particles with too large particle size differences at the same time, too large particle size differences will lead to poor selectivity of the separation medium and reduced capture ability for target minerals, thus affecting the separation efficiency. The classification and separation improve the uniformity of the ore particles to be separated and ensure the separation efficiency of the poly - magnetic medium.

[0020] 2) Adopting the combined filling method of poly - magnetic rod medium and poly - magnetic mesh medium simply and efficiently improves the separation efficiency of the superconducting magnetic separator. By using the combined filling of the medium, poly - magnetic rod medium and poly - magnetic mesh medium matching the particle size grade of the material to be separated are selected to specifically regulate the magnetic field gradient, eliminating the phenomena of magnetic blockage, magnetic wrapping, and magnetic inclusion caused by uneven particle size distribution in a single - type separation medium.

[0021] 3) Optimized the filling methods of the magnetic concentrating rod medium and the magnetic concentrating net medium. By optimizing the surface distance between the wire electrodes of the magnetic concentrating rod medium and the magnetic concentrating net medium that are superposed on each other, adjusting the filling rate of the magnetic concentrating net medium, and controlling conditions such as the medium angle, on the one hand, the magnetic field force action intensity of the magnetic concentrating medium was increased, and the effective capture area of the magnetic concentrating medium was enlarged; on the other hand, the slurry flowability in the separation chamber was improved, the fluid resistance was reduced, the mechanical entrainment phenomenon of gangue minerals on the magnetic concentrating medium was reduced, and the separation efficiency of the superconducting magnetic separator was significantly improved. Description of the Drawings

[0022] Figure 1 is a process flow diagram of the superconducting separation of single molybdenum ore classification.

[0023] Figure 2 is a schematic diagram of the filling method of the separation medium. Specific Embodiments

[0024] The following specific embodiments are intended to further illustrate the content of the present invention rather than limit the protection scope of the claims.

[0025] Example 1

[0026] Superconducting magnetic separation test for a high-clay and low-grade uranium-molybdenum ore in Hebei: 1. Properties of the raw ore In a high-clay and low-grade uranium-molybdenum ore in Hebei, the Mo grade is 0.25% and the U grade is 0.008%. The main mineral compositions in the raw ore are shown in Table 1.

[0027]

[0028] It can be seen from the table that the main gangue minerals in a high-clay and low-grade uranium-molybdenum ore in Hebei are quartz, feldspar and other aluminosilicates, and their content reaches more than 75%. The clay mineral content reaches about 20%, and the mineral types are illite and kaolinite. It can be seen that the content of useful minerals in this ore is only about 5%, showing the characteristics of high clay and high gangue minerals.

[0029] 2. Classification of the ore Using a jaw crusher, the raw ore was crushed to -2 mm and all passed through a sieve, and then directly subjected to wet screening classification. After screening, the particles in the -0.5 mm particle size grade entered the classification and separation process. The coarse-grained particles of -0.5 mm to +0.075 mm entered the coarse-grained separation process, the fine-grained particles of -0.075 mm entered the fine-grained separation process, and the particles above +0.5 mm entered the grinding process. After grinding to 0.5 mm, all passed through a sieve and then entered the same classification and separation process.

[0030] 3. Classification and separation of the ore Coarse-grained particles with a particle size ranging from -0.5 mm to +0.075 mm are fed into a superconducting magnetic separator at a pulp concentration of 15% and a flow rate of 11 L / min, and separated using a coarse-grained separation medium scheme to obtain concentrate I. The specific filling scheme of the coarse-grained separation medium is as follows: The separation medium is a poly-magnetic steel rod with a wire pole spacing of 3 mm and a wire diameter of 3 mm and a poly-magnetic steel mesh with a wire pole spacing of 6 mm and a wire diameter of 1.8 mm; the filling scheme is a cross-over filling of the poly-magnetic steel rod and the poly-magnetic steel mesh in a ratio of 2:1. The wire pole angles of the upper and lower layers of the overlapping poly-magnetic steel rods are maintained at 60°, the surface distance between the wire poles of the upper and lower layers of the overlapping poly-magnetic steel rods and the poly-magnetic steel mesh is maintained at 1.5 mm, and the filling rate of the poly-magnetic steel mesh is maintained at 20%.

[0031] Fine-grained particles with a particle size of -0.075 mm are fed into a superconducting magnetic separator at a pulp concentration of 15% and a flow rate of 11 L / min, and separated using a fine-grained separation medium scheme to obtain concentrate II. The specific filling scheme of the fine-grained separation medium is as follows: The separation medium is a poly-magnetic steel rod with a wire pole spacing of 1.5 mm and a wire diameter of 1.5 mm and a poly-magnetic steel mesh with a wire pole spacing of 2.6 mm and a wire diameter of 1.0 mm; the filling scheme is a cross-over filling of the poly-magnetic steel rod and the poly-magnetic steel mesh in a ratio of 2:1. The wire pole angles of the upper and lower layers of the overlapping poly-magnetic steel rods are maintained at 60°, the surface distance between the wire poles of the upper and lower layers of the overlapping poly-magnetic steel rods and the poly-magnetic steel mesh is maintained at 1 mm, and the filling rate of the poly-magnetic steel mesh is maintained at 15%.

[0032] The results after separation are as follows: Concentrate indexes: The yield of concentrate I is 17.06%, the Mo grade is 0.80%, and the recovery rate is 62.11%.

[0033] The yield of concentrate II is 36.25%, the Mo grade is 0.74%, and the recovery rate is 70.60%. Example 2

[0034] Superconducting magnetic separation test on a high-clay and low-grade uranium-molybdenum ore in Zhangjiakou: 1. Properties of the raw ore The Mo grade in a high-clay and low-grade uranium-molybdenum ore in Zhangjiakou is 0.27%, and the U grade is 0.006%. The main mineral compositions in the raw ore are shown in Table 2.

[0035]

[0036] 2. Classification of the ore The jaw crusher is adopted to crush the raw ore to -2 mm and all of it is screened. Then, wet screening classification is directly carried out. After screening, the particles with a particle size of -0.5 mm enter the classification and separation process. The coarse-grained particles with a size of -0.5 mm to +0.075 mm enter the coarse-grained separation process, the fine-grained particles with a size of -0.075 mm enter the fine-grained separation process, and the particles larger than +0.5 mm enter the grinding process. After grinding to 0.5 mm and all being screened, they enter the same classification and separation process.

[0037] 3. Ore Classification and Separation For the coarse-grained particles with a size of -0.5 mm to +0.075 mm, the pulp concentration is controlled at 10%, and they are fed into the superconducting magnetic separator at a flow rate of 7 L / min. The coarse-grained separation medium filling scheme is used for separation to obtain Concentrate I. The specific coarse-grained separation medium filling scheme is as follows: The separation medium selects poly-magnetic steel rods with a wire pole spacing of 2.5 mm and a wire diameter of 2.5 mm, and poly-magnetic steel meshes with a wire pole spacing of 4.5 mm and a wire diameter of 1.4 mm; the filling scheme is that the poly-magnetic steel rods and poly-magnetic steel meshes are filled in a 2:1 cross-overlapping manner. The wire pole angles of the upper and lower layers of the overlapping poly-magnetic steel rods are kept at 90°, the surface distance between the wire poles of the upper and lower layers of the overlapping poly-magnetic steel rods and poly-magnetic steel meshes is kept at 2 mm, and the filling rate of the poly-magnetic steel mesh is kept at 16%.

[0038] For the fine-grained particles with a size of -0.075 mm, the pulp concentration is controlled at 10%, and they are fed into the superconducting magnetic separator at a flow rate of 7 L / min. The fine-grained separation medium scheme is used for separation to obtain Concentrate II. The specific fine-grained separation medium filling scheme is as follows: The separation medium selects poly-magnetic steel rods with a wire pole spacing of 1.3 mm and a wire diameter of 1.3 mm, and poly-magnetic steel meshes with a wire pole spacing of 1.8 mm and a wire diameter of 0.8 mm; the filling scheme is that the poly-magnetic steel rods and poly-magnetic steel meshes are filled in a 2:1 cross-overlapping manner. Among them, the wire pole angles of the upper and lower layers of the overlapping poly-magnetic steel rods are kept at 90°, the surface distance between the wire poles of the upper and lower layers of the overlapping poly-magnetic steel rods and poly-magnetic steel meshes is kept at 1.5 mm, and the filling rate of the poly-magnetic steel mesh is kept at 11%.

[0039] The results after separation are as follows: Concentrate Index: The yield of Concentrate I is 16.80%, the Mo grade is 0.88%, and the recovery rate is 61.74%.

[0040] The yield of Concentrate II is 35.84%, the Mo grade is 0.78%, and the recovery rate is 69.79%.

[0041] Comparative Example 1 Superconducting magnetic separation test on a high-clay and low-grade uranium-molybdenum ore in Hebei (the separation medium scheme of this comparative example is to use only a single type of medium for filling and does not adopt the preferred medium scheme of the present invention for filling):

[0042] 1. Properties of Raw Ore In a certain high-clay and low-grade uranium-molybdenum ore in Hebei, the Mo grade is 0.25% and the U grade is 0.008%.

[0043] 2. Ore Classification Using a jaw crusher, the raw ore is crushed to -2 mm and all is screened. It is directly wet-screened for classification. After screening, the particles with a particle size in the -0.5 mm size fraction enter the classification and separation process. The coarse-grained particles of -0.5 mm to +0.075 mm enter the coarse-grained separation process, the fine-grained particles of -0.075 mm enter the fine-grained separation process, and the particles above +0.5 mm enter the grinding process. After grinding to 0.5 mm and all being screened, they enter the same classification and separation process again.

[0044] 3. Ore Classification and Separation For the coarse-grained particles with a particle size of -0.5 mm to +0.075 mm, controlling the pulp concentration at 15%, feeding them into the superconducting magnetic separator at a flow rate of 11 L / min. The difference in the separation medium in the superconducting magnetic separator from Example 1 is that: using a poly-magnetic steel rod medium with a wire pole spacing of 3 mm and a wire diameter of 3 mm completely replaces the intermediate layer poly-magnetic steel mesh in Example 1, and the wire pole angles of the mutually stacked poly-magnetic steel rod media in the upper and lower layers are randomly placed, not using the placement method in Example 1, and performing separation to obtain Concentrate Ⅰ.

[0045] For the fine-grained particles with a particle size of -0.075 mm, controlling the pulp concentration at 15%, feeding them into the superconducting magnetic separator at a flow rate of 11 L / min. The difference in the separation medium in the superconducting magnetic separator from Example 1 is that: using a poly-magnetic steel rod medium with a wire pole spacing of 1.5 mm and a wire diameter of 1.5 mm completely replaces the intermediate layer poly-magnetic steel mesh in Example 1, and the wire pole angles of the mutually stacked poly-magnetic steel rod media in the upper and lower layers are randomly placed, not using the placement method in Example 1, and performing separation to obtain Concentrate Ⅱ.

[0046] The results after separation are as follows: Concentrate Indexes: The yield of Concentrate Ⅰ is 12.00%, the Mo grade is 0.70%, and the recovery rate is 38.20%.

[0047] The yield of Concentrate Ⅱ is 25.34%, the Mo grade is 0.79%, and the recovery rate is 52.69%.

[0048] Comparison with Example 2 Superconducting magnetic separation test of a certain high-clay and low-grade uranium-molybdenum ore in Hebei (this comparative example only uses a single type of medium for filling, not using the preferred medium scheme of the present invention for filling):

[0049] 1. Properties of Raw Ore In a certain high-clay and low-grade uranium-molybdenum ore in Hebei, the Mo grade is 0.25% and the U grade is 0.008%.

[0050] 2. Classification of Ore Using a jaw crusher, the raw ore is crushed to -2 mm and all is screened. It is directly wet-screened and classified. After screening, the particles with a particle size of -0.5 mm enter the classification and separation process. The coarse-grained particles of -0.5 mm to +0.075 mm enter the coarse-grained separation process, the fine-grained particles of -0.075 mm enter the fine-grained separation process, and the particles above +0.5 mm enter the grinding process. After grinding to 0.5 mm and all being screened, they enter the same classification and separation process again.

[0051] 3. Classification and Separation of Ore For the coarse-grained particles with a particle size of -0.5 mm to +0.075 mm, controlling the pulp concentration at 15%, they are fed into the superconducting magnetic separator at a flow rate of 11 L / min. The difference in the separation medium in the superconducting magnetic separator from Example 1 is that: a poly-magnetic steel mesh medium with a wire pole spacing of 6 mm and a wire diameter of 1.8 mm is used to completely replace each layer of poly-magnetic steel rods in the upper and lower layers of Example 1, and the others are the same as in Example 1, and separation is carried out to obtain Concentrate I.

[0052] For the fine-grained particles with a particle size of -0.075 mm, controlling the pulp concentration at 15%, they are fed into the superconducting magnetic separator at a flow rate of 11 L / min. The difference in the separation medium in the superconducting magnetic separator from Example 1 is that: a poly-magnetic steel mesh medium with a wire pole spacing of 2.6 mm and a wire diameter of 1.0 mm is used to completely replace each layer of poly-magnetic steel rods in the upper and lower layers of Example 1, and the others are the same as in Example 1, and separation is carried out to obtain Concentrate II.

[0053] The results after separation are as follows: Concentrate Indexes: The yield of Concentrate I is 33.95%, the Mo grade is 0.44%, and the recovery rate is 67.90%.

[0054] The yield of Concentrate II is 46.68%, the Mo grade is 0.57%, and the recovery rate is 70.02%.

[0055] Comparison with Example 3 Superconducting magnetic separation test on a high-clay low-grade uranium-molybdenum ore in Hebei (this example is a comparative example, using the preferred medium scheme of the present invention to fill the separation medium, but not performing the classification and separation of the ore):

[0056] 1. Properties of Raw Ore In a high-clay low-grade uranium-molybdenum ore in Hebei, the Mo grade is 0.25% and the U grade is 0.008%.

[0057] 2. Separation of Ore Using a jaw crusher, the raw ore is crushed to -2 mm and all is screened. It is directly subjected to wet screening and classification. After screening, the particle size of -0.5 mm is fed into a superconducting magnetic separator for separation. The pulp concentration is controlled at 15%, the pulp flow rate is 11 L / min, and the separation medium is a poly-magnetic steel rod with a wire pole spacing of 3 mm and a wire diameter of 3 mm, and a poly-magnetic steel mesh with a wire pole spacing of 6 mm and a wire diameter of 1.8 mm; the filling scheme is that the number of poly-magnetic steel rods and poly-magnetic steel meshes is cross-stacked and filled in a ratio of 2:1. The wire pole angles of the upper and lower layers of the mutually stacked poly-magnetic steel rods are maintained at 60°, the surface distance between the wire poles of the upper and lower layers of the mutually stacked poly-magnetic steel rods and poly-magnetic steel meshes is maintained at 1.5 mm, and the filling rate of the poly-magnetic steel mesh is maintained at 20% to obtain concentrate by separation.

[0058] The results after separation are as follows: Concentrate indexes: The concentrate yield is 17.56%, the Mo grade is 0.84%, and the recovery rate is 59.00%.

[0059] From the separation indexes of the above embodiments, it can be seen that after the uranium-molybdenum ore adopts the separation medium filling method proposed by the present invention, the concentrate grade and recovery rate indexes have shown obvious improvements; the present invention optimizes the separation environment of the poly-magnetic medium, directly driving the improvement of the upper limit of the separation efficiency of the superconducting magnetic separator, which is undoubtedly of great significance for the future application prospect of the superconducting magnetic separation equipment in the field of metal ore separation.

Claims

1. A method for uranium-molybdenum ore beneficiation and enrichment based on superconducting magnetic separation, characterized in that: The following steps are involved: 1) The uranium-molybdenum ore is crushed and sieved to classify the particles within the range of -0.5mm to +0.075mm as coarse particles, and the particles within the range of -0.075mm as fine particles; 2) The coarse-grained fraction is fed into a superconducting magnetic separator I after slurry adjustment for magnetic separation I to obtain a concentrate I; the separation medium in the superconducting magnetic separator includes a magnetic steel rod I and a magnetic steel mesh I, and the filling method is as follows: the upper layer is a double-layer magnetic steel rod, the middle layer is a single-layer magnetic steel mesh, and the lower layer is a double-layer magnetic steel rod, which are stacked and filled in sequence; wherein the filament angle between the two layers of magnetic steel rods in the upper layer is maintained at 60° to 90°, and the surface distance of the filament between the middle layer and the upper layer and the lower layer is 1.5 to 2 mm; the filling rate of the magnetic steel mesh in the middle layer is 16% to 20%, and the filament angle between the two layers of magnetic steel rods in the lower layer is maintained at 60° to 90°; 3) The fine-grained fraction is fed into a superconducting magnetic separator II after slurry adjustment for magnetic separation II to obtain concentrate II; the separation medium in the superconducting magnetic separator includes magnetic steel rods II and magnetic steel mesh II, and the filling method is: the upper layer is a double-layer magnetic steel rod, the middle layer is a single-layer magnetic steel mesh, and the lower layer is a double-layer magnetic steel rod, which are stacked and filled in sequence; wherein, the filament angle between the two layers of magnetic steel rods in the upper layer is maintained at 60° to 90°, and the filament surface distance between the middle layer and the upper layer and the lower layer is 1.0 to 1.5 mm; the filling rate of the magnetic steel mesh in the middle layer is 11% to 15%, and the filament angle between the two layers of magnetic steel rods in the lower layer is maintained at 60° to 90°.

2. The method for uranium-molybdenum ore beneficiation and enrichment based on superconducting magnetic separation according to claim 1, characterized in that: The wire pole spacing of the magnetic steel rod I is 2.5mm-3mm, and the wire diameter is 2.5mm-3mm; The wire pole spacing of the magnetic steel mesh I is 4.5mm-6mm, and the wire diameter is 1.4mm-1.8mm.

3. A method for uranium-molybdenum ore beneficiation and enrichment based on superconducting magnetic separation according to claim 1 or 2, characterized in that: The coarse particle size is slurried to a mass concentration of 10% to 15%.

4. A method for uranium-molybdenum ore beneficiation and enrichment based on superconducting magnetic separation according to claim 1 or 2, characterized in that: The slurry feeding rate of the magnetic separation I is 7 to 11 L / min.

5. The method for uranium-molybdenum ore beneficiation and enrichment based on superconducting magnetic separation according to claim 1, characterized in that: The wire pole spacing of the magnetic steel rod II is 1.3mm-1.5mm, and the wire diameter is 1.3mm-1.5mm; The wire pole spacing of the magnetic steel mesh II is 1.8mm-2.6mm, and the wire diameter is 0.8mm-1.0mm.

6. A method for uranium-molybdenum ore beneficiation and enrichment based on superconducting magnetic separation according to claim 1 or 5, characterized in that: The fine particle size is slurried to a mass concentration of 10% to 15%.

7. A method for uranium-molybdenum ore beneficiation and enrichment based on superconducting magnetic separation according to claim 1 or 5, characterized in that: The slurry feeding rate of the magnetic separation II is 7 to 11 L / min.

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