A copper-containing magnetite wet pre-selection grinding and classification system and pre-selection process

Abstract

The invention discloses a wet pre-selection grinding and grading system for copper-containing magnetite and its pre-selection process, belonging to the technical field of ore beneficiation. The wet pre-selection grinding and grading system of the invention comprises a crushing and screening device, a wet magnetic separator, a vibrating screen 1, a ball mill, a vibrating screen 2 and a hydrocyclone arranged in sequence according to the production process. The concentrate product outlet of the wet magnetic separator is connected to the feed port of the vibrating screen 1, and the tailings product outlet of the wet magnetic separator is connected to the feed port of the vibrating screen 2; the upper product outlet of the vibrating screen 1 is connected to the feed port of the ball mill, and the discharge port of the ball mill, the under-screen product outlet of the vibrating screen 2 and the under-screen product outlet of the vibrating screen 1 are all connected to the feed port of the hydrocyclone; the upper product outlet of the vibrating screen 2 is connected to the tailings area; and the overflow port of the hydrocyclone is connected to the sorting device. The invention performs secondary processing on the tailings selected by wet magnetic separation and circulates the ball mill together with the concentrate selected by wet magnetic separation in the hydrocyclone, thereby achieving the technical effect of collecting all the copper elements.

Description

Technical Field

[0001] The invention belongs to the technical field of ore dressing, and more specifically, relates to a copper-containing magnetite wet pre-selection grinding and classification system and a pre-selection process thereof. Background Art

[0002] With the acceleration of domestic mining resources mining speed year by year, my country's mining resources have become less rich ores, more poor ores, poor ore properties, low crystal size, and difficult to separate. Faced with the actual situation of "poor, fine, and mixed" ore, traditional mineral processing technology has gradually been replaced by efficient, intelligent and targeted design of mineral processing technology for different ore properties. As the ore properties deteriorate year by year, the mining grade decreases year by year, which has a great impact on the operating cost of the mineral processing plant. Due to the low ore grade, the ore entering the mill has a low grade, a large amount of ore entering the mill, high grinding cost, and low efficiency. In view of this situation, the pre-grinding pre-selection process for poor ore has become an indispensable part of the mineral processing process of the mineral processing plant.

[0003] If the conventional magnetic pulley dry pre-selection and tailings discarding technology is used for the raw iron ore containing copper magnetite, since chalcopyrite is a weakly magnetic mineral, it will enter the tailings together with the gangue minerals, resulting in a large loss of copper elements in the tailings, causing process waste and affecting the economic benefits of the enterprise.

[0004] After searching, the Chinese patent publication number is CN107876214A, and the publication date is April 6, 2018. A method for separating copper-containing magnetite ore is disclosed, which solves the problems of high copper loss rate in magnetic separation operation and excessive sulfur content in iron concentrate in the traditional "first magnetic and then flotation" process. The technical scheme of the invention is carried out in the following manner: (1) After the raw ore is ground, a weak magnetic roughing is first performed, and a part of it is obtained by weak magnetic separation tailings, and a part of it enters the magnetic field screening machine for selection to obtain iron concentrate and magnetic field screening machine tailings; (2) The weak magnetic separation tailings and magnetic field screening machine tailings are flotated to obtain copper concentrate and tailings. The invention is aimed at copper-containing skarn-type magnetite ore, and the method of weak magnetic roughing-magnetic field screening machine selection is used to recover iron, and the magnetic separation tailings are then flotated to recover copper. However, the invention does not have a pre-selection operation, the raw ore is directly ground, and the "early throwing when possible" is not implemented, and the ore dressing cost is relatively high. Summary of the invention

[0005] 1. Problems to be solved

[0006] Aiming at the problem that the copper element is discarded too early in the pre-selection process of the copper-containing magnetite ore in the prior art, resulting in waste of resources, the present invention provides a wet pre-selection grinding and grading system for copper-containing magnetite and its pre-selection process, which adopts wet pre-grinding magnetic separation, and screens the tailings selected by wet magnetic separation, and the screened products are sold as building materials; the screened products and the concentrate selected by wet magnetic separation are simultaneously circulated in the hydrocyclone ball mill, and the overflow products of the hydrocyclone enter the subsequent selection operation for magnetite and chalcopyrite selection. The present invention implements the pre-grinding pre-selection process for the copper-containing magnetite and implements "early discarding when possible", which not only achieves the effect of energy saving and consumption reduction, but also comprehensively utilizes the tailings as building materials, and also achieves the technical effect of collecting all the copper elements that should be collected.

[0007] 2. Technical solution

[0008] To solve the above problems, the present invention adopts the following technical solutions:

[0009] A copper-containing magnetite wet pre-selection grinding and grading system comprises a crushing and screening device, a wet magnetic separator, a vibrating screen 1 and a ball mill arranged in sequence according to a production process, and further comprises a vibrating screen 2 and a hydrocyclone, wherein the concentrate product outlet of the wet magnetic separator is connected to the feed inlet of the vibrating screen 1, and the tailings product outlet of the wet magnetic separator is connected to the feed inlet of the vibrating screen 2; the over-screen product outlet of the vibrating screen 1 is connected to the feed inlet of the ball mill, and the discharge port of the ball mill, the under-screen product discharge port of the vibrating screen 2 and the under-screen product discharge port of the vibrating screen 1 are all connected to the feed inlet of the hydrocyclone; the over-screen product discharge port of the vibrating screen 2 is connected to the tailings area; and the overflow port of the hydrocyclone is connected to the selection device.

[0010] Furthermore, the discharge port of the ball mill, the discharge port of the undersize product of the second vibrating screen and the discharge port of the undersize product of the first vibrating screen are all connected to the slurry pool; the slurry pool is connected to the hydrocyclone through a slurry pump, thereby achieving the purpose of automated circulation production and improving production efficiency.

[0011] Furthermore, the crushing and screening device is a three-stage closed-circuit crushing device; the wet magnetic separator is an external magnetic magnetic separator; the vibrating screen 1 and the vibrating screen 2 are both linear vibrating screens, which have high screening efficiency for wet magnetic separation products; the ball mill is a one-stage overflow ball mill; the grit discharge port of the hydrocyclone is connected to the feed port of the ball mill.

[0012] Furthermore, it is suitable for copper-containing magnetite ores with a TFe content of not less than 20%, a magnetic rate of not less than 65%, and a copper content of not more than 0.12%. If the process is used when the copper content is too high, the copper element will be lost greatly after the tailings are discarded in step three, and the purpose of discarding the copper-containing magnetite as early as possible and collecting as much copper as possible cannot be achieved. The ball mill and the hydrocyclone form an integrated closed-circuit grinding and classification system, which improves the grinding and classification efficiency.

[0013] Furthermore, the magnetic system of the external magnetic separator adopts a permanent magnetic system, the feed concentration is 30-50%, and the magnetic field strength is 0.4-0.5T.

[0014] Furthermore, the mesh sizes of the first and second vibrating screens are 0.5-2 mm and 0.5-0.8 mm respectively. The mesh size of the second vibrating screen is best at 0.5 mm. The products on the screen are discarded, and the products under the screen are returned to the ball mill. The mesh size of 0.5 mm can enrich the copper element in the copper-containing magnetite ore, so as to achieve both the early discarding of the copper-containing magnetite tailings and the recovery of the copper element in the tailings.

[0015] A pre-selection process of a copper-containing magnetite wet pre-selection grinding and classification system, the steps are as follows:

[0016] Step 1, crushing and screening: using a three-stage one-closed-circuit crushing device to carry out a three-stage one-closed-circuit conventional crushing process to crush the copper-containing magnetite ore, and screening the crushed product, and the screened product is the copper magnetite ore particles;

[0017] Step 2, wet coarse particle selection and ball milling: the copper magnetite ore particles after screening are transferred to the external magnetic separator for wet magnetic separation, and the concentrate product after magnetic separation is screened by a vibrating screen and the screened product is fed into a ball mill for ball milling;

[0018] Step 3: Screening of tailings products: The tailings separated by wet magnetic separation are screened by vibrating screen 2; the screened products have low copper content and can be directly discharged, which can reduce the grinding amount of subsequent ball milling operations, save mineral processing production costs, and avoid the loss of copper elements as much as possible;

[0019] Step 4, hydrocyclone classification: the discharge ore after ball milling in step 2, the undersize product after screening by vibrating screen 1 of the concentrate product and the undersize product after screening by vibrating screen 2 in step 3 are fed into the hydrocyclone for classification, the sedimentation of the hydrocyclone and the oversize product after screening by vibrating screen 1 are ball milled together, and the ball mill and the hydrocyclone form a closed-circuit grinding system; the overflow product of the hydrocyclone enters the subsequent separation device for separation of magnetite and chalcopyrite.

[0020] Furthermore, in step one, the crushing particle size is preferably -20 mm; in step two, the feed concentration is 30-40%, the magnetic field strength is 0.4-0.5 T, and the feed concentration in the first-stage ball mill is 70-80%; in step three, the sieved product is sold as a building material product.

[0021] 3. Beneficial effects

[0022] Compared with the prior art, the present invention has the following beneficial effects:

[0023] (1) A wet pre-selection grinding and classification system and pre-selection process of copper-containing magnetite of the present invention, by adding a wet pre-selection screening process consisting of wet coarse particle magnetic separation and vibrating screen screening between the finely crushed product and the first stage ball milling and classification system, not only realizes the wet tailings of the copper-containing magnetite, reduces the grinding amount of the subsequent ball milling operation, and saves the ore dressing production cost, but also comprehensively utilizes the coarse particle tailings on the screen product and the copper-containing high screen product to return to the grinding and classification system, effectively avoiding the loss of copper metal in the tailings, but also achieving the effect of enriching the copper element, achieving the purpose of reducing costs and increasing efficiency;

[0024] (2) A copper-containing magnetite wet pre-selection grinding and classification system and pre-selection process of the present invention are suitable for copper-containing magnetite with a TFe content of not less than 20%, a magnetic rate of not less than 65%, and a copper content of not more than 0.12%. The inventors found in actual application that if the copper content is too high, exceeding 0.12%, the copper loss after discarding the tailings in step 3 is large when using this process, and the technical effect of both discarding the copper-containing magnetite early and collecting the copper can be achieved. However, for copper-containing magnetite with a copper content of not more than 0.12%, the present process can improve the TFe percentage while the comprehensive benefits generated are much higher than the cost caused by the loss of copper.

[0025] (3) A copper-containing magnetite wet pre-selection grinding and classification system and pre-selection process of the present invention, the vibrating screen mesh size of the screening in step 3 is 0.5-0.8 mm, wherein the size of 0.5 mm is the best, the product on the screen is discarded, and the product under the screen is returned to the ball mill. The inventors found in practice that the 0.5 mm mesh can enrich the copper element in the copper-containing magnetite ore, and can achieve the technical effect of taking into account the early disposal of the copper-containing magnetite tailings and the recovery of the copper element in the tailings;

[0026] (4) A copper-containing magnetite wet pre-selection grinding and classification system and pre-selection process of the present invention, the undersize product of the vibrating screen and the discharge product of the ball mill are fed into the same pump pool, and then fed into the hydrocyclone through a slurry pump, thereby achieving the purpose of automated cyclic production and improving production efficiency;

[0027] (5) The present invention provides a copper-containing magnetite wet pre-selection grinding and classification system and its pre-selection process. The ball mill and the hydrocyclone form an integrated closed-circuit grinding and classification system with high grinding and classification efficiency. The linear vibrating screen used for vibration screening has high screening efficiency for wet magnetic separation products. BRIEF DESCRIPTION OF THE DRAWINGS

[0028] Figure 1 It is a schematic diagram of the distribution of the wet pre-selection grinding and classification system of the present invention;

[0029] Figure 2This is a schematic diagram of the distribution of the wet pre-selection grinding and classification system of Example 2;

[0030] Figure 3 It is a flow chart of the preselection process of the present invention.

[0031] In the figure: 1. Raw ore silo; 2. Crushing and screening device; 3. Wet magnetic separator; 4. Vibrating screen 1; 5. Ball mill; 6. Hydrocyclone; 7. Sorting device; 8. Slurry pool; 9. Slurry pump; 10. Building materials products; 31. Vibrating screen 2. DETAILED DESCRIPTION

[0032] The present invention is further described below in conjunction with specific embodiments and drawings.

[0033] Example 1

[0034] like Figure 1 As shown, the copper-containing magnetite wet pre-selection grinding and grading system of this embodiment includes a crushing and screening device 2, a wet magnetic separator 3, a vibrating screen 4 and a ball mill 5 arranged in sequence according to the production process, and also includes a vibrating screen 31 and a hydrocyclone 6, wherein the concentrate product outlet of the wet magnetic separator 3 is connected to the feed port of the vibrating screen 4, and the tailings product outlet of the wet magnetic separator 3 is connected to the feed port of the vibrating screen 31; the over-screen product outlet of the vibrating screen 4 is connected to the feed port of the ball mill 5, and the discharge port of the ball mill 5, the under-screen product discharge port of the vibrating screen 31 and the under-screen product discharge port of the vibrating screen 4 are all connected to the feed port of the hydrocyclone 6; the over-screen product discharge port of the vibrating screen 31 is connected to the tailings area; the overflow port of the hydrocyclone 6 is connected to the sorting device 7. The crushing and screening device 2 is a three-stage closed-circuit crushing device; the wet magnetic separator 3 is an external magnetic magnetic separator; the vibrating screen 1 4 and the vibrating screen 2 31 are both linear vibrating screens, which have high screening efficiency for wet magnetic separation products; the ball mill 5 is a one-stage overflow ball mill; the sand settling outlet of the hydrocyclone 6 is connected to the feed port of the ball mill 5.

[0035] The pre-selection process of the copper-containing magnetite wet pre-selection grinding and classification system of this embodiment has the following steps: the TFe grade of the iron ore is 38.45%, the occupancy rate of magnetic iron in the ore is 81.33%, and the copper content is 0.053%.

[0036] Step 1, crushing and screening: a three-stage one-closed-circuit crushing device is used to carry out a three-stage one-closed-circuit conventional crushing process to crush the copper-containing magnetite ore in the raw ore silo 1, and the particle size of the crushed product is -12mm, that is, it passes through a mesh screen with a sieve hole of 12mm, and the crushed product is screened, and the screened product is copper magnetite ore particles;

[0037] Step 2, wet coarse particle selection and ball milling: the copper magnetite ore particles after screening are transferred to an external magnetic separator for wet magnetic separation, the magnetic field strength is 0.40T, the feed concentration is 35%, the rotation speed is 14 rpm, and the yield of the magnetic tailings product is 18.6% (TFe content is 9.75%, Cu 0.97%); the TFe grade of the magnetic concentrate obtained is 45.0%; the concentrate product after magnetic separation is screened by a vibrating screen-4, and the screen product is fed into a ball mill for ball milling;

[0038] Step 3, screening of tailings products: the tailings separated by wet magnetic separation are screened by a vibrating screen 2 31; the screen size is 0.5mm-0.8mm, preferably 0.5mm, and the screened product with an ore yield of 9.63% is obtained and sold as a building material product 10, reducing the grinding amount of subsequent ball milling operations; after testing, the TFe content in the product is only 9.04%, and the copper content is 0.074%; the under-0.5mm product TFe10.51%, Cu 0.12%, and the copper element is effectively enriched in the under-0.5mm product; that is, the 9.63% over-screen tailings product accounts for a small proportion, and the copper content is low, so the tailings can be directly discharged as building materials, reducing the grinding amount of subsequent ball milling operations, saving the ore dressing production cost, and avoiding the loss of copper elements as much as possible;

[0039] Step 4: Dehydration of the concentrate product of the external magnetic separator: The concentrate product of the external magnetic separator is concentrated and graded by a linear vibrating screen with a screen size of 0.5 mm. The product on the screen is directly fed into a first-stage ball mill. The first-stage ball mill and the hydrocyclone form a first-stage ball milling and grading closed-circuit system;

[0040] Step 5, hydrocyclone classification: the discharge ore after ball milling in step 2, the undersize product after screening by vibrating screen 4 of the concentrate product and the undersize product after screening by vibrating screen 2 31 in step 3 are fed into the hydrocyclone 6 for classification, the sedimentation sand of the hydrocyclone 6 and the oversize product after screening by vibrating screen 4 are ball milled together, the grinding concentration of the ball milling is 70-80%, and the ball mill and the hydrocyclone form a closed-circuit grinding; the overflow product of the hydrocyclone 6 enters the subsequent separation device 7 for separation of magnetite and chalcopyrite, and the yield of the overflow product is 98.37% for the original ore, 41.56 for TFe, and 0.05% for Cu.

[0041] By using the wet pre-selection grinding and classification system and pre-selection process of this embodiment, the TFe grade in the original ore is increased by 3.11 percentage points, and the Cu content is only reduced by 0.003 percentage points. A tailings TFe9.04% with a yield of 9.63% and a copper content of 0.074% is obtained, which can be sold as a building material product 10, thereby achieving the purpose of reducing costs and increasing efficiency.

[0042] Example 2

[0043] like Figure 2 As shown, the copper-containing magnetite wet pre-selection grinding and classification system of this embodiment has the same basic structure as that of Example 1.

[0044] The pre-selection process of the copper-containing magnetite wet pre-selection grinding and classification system of this embodiment has the following steps: the TFe grade of the iron ore is 25.00%, the occupancy rate of magnetic iron in the ore is 77.50%, and the copper content is 0.06%.

[0045] Step 1, crushing and screening: a three-stage one-closed-circuit crushing device is used to carry out a three-stage one-closed-circuit conventional crushing process to crush the copper-containing magnetite ore, and the particle size of the crushed product is -12mm, that is, it passes through a mesh screen with a sieve hole of 12mm, and the crushed product is screened, and the screened product is the copper-containing magnetite ore particles;

[0046] Step 2, wet coarse particle selection and ball milling: the copper magnetite ore particles after screening are transferred to an external magnetic separator for wet magnetic separation, the magnetic field strength is 0.45T, the feed concentration is 35%, the rotation speed is 14 rpm, and the yield of the magnetic tailings product is 32.61% (TFe content is 9.5%, Cu 0.105%); the magnetic concentrate TFe grade is 32.5%; the concentrate product after magnetic separation is screened by a vibrating screen-4, and the screen product is fed into a ball mill for ball milling;

[0047] Step 3, screening of tailings products: the tailings separated by wet magnetic separation are screened by a vibrating screen 31; the screen size is 0.5mm-0.8mm, preferably 0.5mm, and the screened product with an ore yield of 18.91% is obtained and sold as a building material product 10, reducing the grinding amount of subsequent ball milling operations; after testing, the TFe content in the product is only 8.95%, and the copper content is 0.08%; the under-0.5mm product TFe10.26%, Cu 0.14%, and the copper element is effectively enriched in the under-0.5mm product; that is, the 18.91% over-screen tailings product has a low copper content and can be directly discharged as building materials, reducing the grinding amount of subsequent ball milling operations, saving the ore dressing production cost, and avoiding the loss of copper as much as possible;

[0048] Step 4: Dehydration of the concentrate product of the external magnetic separator: The concentrate product of the external magnetic separator is concentrated and graded by a linear vibrating screen with a screen size of 0.5 mm. The product on the screen is directly fed into a first-stage ball mill. The first-stage ball mill and the hydrocyclone form a first-stage ball milling and grading closed-circuit system;

[0049] Step 5: Hydrocyclone classification: Figure 2As shown, the ore discharge after ball milling in step 2, the undersize product after screening by vibrating screen 4 of the concentrate product, and the undersize product after screening by vibrating screen 2 31 in step 3 are fed into the slurry pool 8, and the slurry pool 8 is connected to the hydrocyclone 6 through a slurry pump 9, that is, the product in the slurry pool 8 is transferred to the hydrocyclone 6 for classification, and the sand settling of the hydrocyclone 6 and the oversize product after screening by vibrating screen 4 are ball milled together, the grinding concentration of the ball mill is 70-80%, and the ball milling is cyclic; the overflow product of the hydrocyclone 6 enters the subsequent separation device 7 for separation of magnetite and chalcopyrite, and the yield of the overflow product is 81.09% of the original ore, 28.74% of TFe, and 0.055% of Cu.

[0050] By using the wet pre-selection grinding and classification system and pre-selection process of this embodiment, the TFe grade in the original ore is increased by 3.74 percentage points, and the Cu content is only reduced by 0.005 percentage points. A tailings TFe8.95% with a yield of 18.91% and a copper content of 0.08% is obtained, which can be sold as a building material product 10, thereby achieving the purpose of reducing costs and increasing efficiency.

[0051] Example 3

[0052] The copper-containing magnetite wet pre-selection grinding and classification system of this embodiment has the same basic structure as that of embodiment 2;

[0053] In the pre-selection process of the copper-containing magnetite wet pre-selection grinding and classification system of this embodiment, the copper-containing magnetite ore TFe grade is 30.66%, the occupancy rate of magnetic iron in the ore is 65.85%, and the copper content is 0.12%. Figure 3 As shown, the pre-selection process is as follows:

[0054] Step 1, crushing and screening: a three-stage one-closed-circuit crushing device is used to carry out a three-stage one-closed-circuit conventional crushing process to crush the copper-containing magnetite ore, and the particle size of the crushed product is -12mm, that is, it passes through a mesh screen with a sieve hole of 12mm, and the crushed product is screened, and the screened product is copper magnetite ore particles;

[0055] Step 2, wet coarse particle selection and ball milling: the copper magnetite ore particles after screening are transferred to an external magnetic separator for wet magnetic separation, with a magnetic field strength of 0.5T, a feed concentration of 40%, a rotation speed of 14 rpm, and a magnetic tailings product yield of 30.61% (TFe content of 8.65%, Cu 0.135%); the magnetic concentrate TFe grade is 35.5%; the concentrate product after magnetic separation is screened by a vibrating screen-4, and the screen product is fed into a ball mill for ball milling;

[0056] Step 3, screening of tailings products: the tailings separated by wet magnetic separation are screened by a vibrating screen 2 31; the screen size is 0.5mm-0.8mm, preferably 0.5mm, and the screened product with an ore yield of 17.91% is obtained and sold as a building material product 10, reducing the grinding amount of subsequent ball milling operations; after testing, the TFe content in the product is only 9.65%, and the copper content is 0.126%; the under-0.5mm product TFe15.26%, Cu 0.214%, and the copper element is effectively enriched in the under-0.5mm product; that is, 17.91% of the over-screen tailings product has a low copper content and can be directly discharged as building materials, reducing the grinding amount of subsequent ball milling operations, saving the ore dressing production cost, and avoiding the loss of copper as much as possible;

[0057] Step 4: Dehydration of the concentrate product of the external magnetic separator: The concentrate product of the external magnetic separator is concentrated and graded by a linear vibrating screen with a screen size of 0.5 mm. The product on the screen is directly fed into a first-stage ball mill. The first-stage ball mill and the hydrocyclone form a first-stage ball milling and grading closed-circuit system;

[0058] Step 5, hydrocyclone classification: the discharge ore after ball milling in step 2, the undersize product after screening by vibrating screen 4 of the concentrate product and the undersize product after screening by vibrating screen 2 31 in step 3 are fed into the slurry pool 8, and the slurry pool 8 is connected to the hydrocyclone 6 through a slurry pump 9, that is, the product in the slurry pool 8 is transferred to the hydrocyclone 6 for classification, and the sedimentation of the hydrocyclone 6 and the oversize product after screening by vibrating screen 4 are ball milled together, the grinding concentration of the ball mill is 70-80%, and the ball milling is cyclic; the overflow product of the hydrocyclone 6 enters the subsequent separation device 7 for separation of magnetite and chalcopyrite, and the yield of the overflow product is 82.59% for the original ore, 36.74 for TFe, and 0.116% for Cu.

[0059] By using the wet pre-selection grinding and classification system and pre-selection process of this embodiment, the TFe grade in the original ore is increased by 6.08 percentage points, and the Cu content is only reduced by 0.004 percentage points. A tailings TFe9.65% with a yield of 17.91% and a copper content of 0.126% is obtained, which can be sold as a building material product 10, thereby achieving the purpose of reducing costs and increasing efficiency.

[0060] Comparative Example

[0061] The copper-containing magnetite wet pre-selection grinding and classification system of this embodiment has the same basic structure as that of embodiments 2 and 3;

[0062] The pre-selection process of the copper-containing magnetite wet pre-selection grinding and classification system of this embodiment has the same steps as those of Embodiments 2 and 3;

[0063] The copper-containing magnetite ore of this embodiment has a TFe grade of 31.16%, a magnetic iron occupancy rate of 68.15% in the ore, and a copper element content of 0.13%.

[0064] In step three, an over-screen product with an ore yield of 16.44% is obtained. After testing, the TFe content in the product is 11.02%, and the copper content is 0.144%. The product with a copper content of 0.144% has certain flotation and smelting value. If the product is sold as a building material product 10, it will still cause a waste of copper. Therefore, combined with Example 3, if the copper content exceeds 0.12%, it is not suitable to use this process.

[0065] The examples described in the present invention are merely descriptions of the preferred implementation modes of the present invention, and are not intended to limit the concept and scope of the present invention. Without departing from the design concept of the present invention, various modifications and improvements made to the technical solutions of the present invention by engineers and technicians in this field should all fall within the protection scope of the present invention.

Claims

1. A copper-containing magnetite wet pre-selection grinding and classification system, comprising a crushing and screening device (2), a wet magnetic separator (3), a vibrating screen (4) and a ball mill (5) arranged in sequence according to the production process, characterized in that: It also includes a second vibrating screen (31) and a hydrocyclone (6), wherein the concentrate product outlet of the wet magnetic separator (3) is connected to the feed port of the first vibrating screen (4), and the tailings product outlet of the wet magnetic separator (3) is connected to the feed port of the second vibrating screen (31); the oversize product outlet of the first vibrating screen (4) is connected to the feed port of the ball mill (5), and the discharge port of the ball mill (5), the undersize product discharge port of the second vibrating screen (31) and the undersize product discharge port of the first vibrating screen (4) are all connected to the feed port of the hydrocyclone (6); the oversize product discharge port of the second vibrating screen (31) is connected to the tailings area; and the overflow port of the hydrocyclone (6) is connected to the sorting device (7); The discharge port of the ball mill (5), the discharge port of the undersize product of the second vibrating screen (31), and the discharge port of the undersize product of the first vibrating screen (4) are all connected to the slurry pool (8); the slurry pool (8) is connected to the hydrocyclone (6) via a slurry pump (9); The crushing and screening device (2) is a three-stage closed-circuit crushing device; the wet magnetic separator (3) is an external magnetic separator; the vibrating screen 1 (4) and the vibrating screen 2 (31) are both linear vibrating screens; the ball mill (5) is a one-stage overflow ball mill; the grit discharge port of the hydrocyclone (6) is connected to the feed port of the ball mill (5); It is suitable for copper-containing magnetite ores with a TFe content of not less than 20%, a magnetic rate of not less than 65%, and a copper content of not more than 0.12%. The ball mill (5) and the hydrocyclone (6) form an integrated closed-circuit grinding and classification system. The magnetic system of the external magnetic separator adopts a permanent magnetic system, the feed concentration is 30-50%, and the magnetic field strength is 0.4-0.5T; The mesh sizes of the vibration screen 1 (4) and the vibration screen 2 (31) are 0.5-2 mm and 0.5-0.8 mm respectively.

2. A pre-selection process of the copper-containing magnetite wet pre-selection grinding and classification system according to claim 1, characterized in that: Here are the steps: Step 1, crushing and screening: using a three-stage one-closed-circuit crushing device to carry out a three-stage one-closed-circuit conventional crushing process to crush the copper-containing magnetite ore, and screening the crushed product, and the screened product is the copper-containing magnetite ore particles; Step 2, wet coarse particle selection and ball milling: the screened copper-containing magnetite particles are transferred to an external magnetic separator for wet magnetic separation. The concentrate product after magnetic separation is screened by a vibrating screen (4), and the screened product is fed into a first-stage ball mill for ball milling; Step 3: Screening of tailings products: The tailings separated by wet magnetic separation are screened by vibrating screen 2 (31); Step 4: hydrocyclone classification: the ore discharge after ball milling in step 2, the concentrate product, the undersize product after screening by vibrating screen 1 (4), and the undersize product after screening by vibrating screen 2 (31) in step 3 are fed into a hydrocyclone (6) for classification; the sediment in the hydrocyclone (6) and the oversize product after screening by vibrating screen 1 (4) are ball milled together; the overflow product of the hydrocyclone (6) enters a subsequent separation device (7) for separation of magnetite and chalcopyrite.

3. The pre-selection process of a copper-containing magnetite wet pre-selection grinding and classification system according to claim 2, characterized in that: In step 1, the maximum particle size of the crushing is no more than 20 mm; in step 2, the feed concentration is 30-40%, the magnetic field strength is 0.4-0.5 T, and the grinding concentration in the first-stage ball mill is 70-80%; in step 3, the sieved product is sold as a building material product (10).

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