CN112619910A - Method for improving classification efficiency of cyclone iron ore slurry - Google Patents
Method for improving classification efficiency of cyclone iron ore slurry Download PDFInfo
- Publication number
- CN112619910A CN112619910A CN202011359824.XA CN202011359824A CN112619910A CN 112619910 A CN112619910 A CN 112619910A CN 202011359824 A CN202011359824 A CN 202011359824A CN 112619910 A CN112619910 A CN 112619910A
- Authority
- CN
- China
- Prior art keywords
- cyclone
- ore
- feeding
- sand setting
- phi
- Prior art date
- Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
- Pending
Links
- XEEYBQQBJWHFJM-UHFFFAOYSA-N Iron Chemical compound [Fe] XEEYBQQBJWHFJM-UHFFFAOYSA-N 0.000 title claims abstract description 118
- 229910052742 iron Inorganic materials 0.000 title claims abstract description 59
- 238000000034 method Methods 0.000 title claims abstract description 31
- 239000002002 slurry Substances 0.000 title claims description 25
- 239000004576 sand Substances 0.000 claims abstract description 83
- 238000000227 grinding Methods 0.000 claims abstract description 38
- 239000000843 powder Substances 0.000 claims abstract description 21
- 238000012797 qualification Methods 0.000 claims abstract description 4
- 238000005299 abrasion Methods 0.000 claims description 9
- 238000003780 insertion Methods 0.000 claims description 9
- 230000037431 insertion Effects 0.000 claims description 9
- 230000000087 stabilizing effect Effects 0.000 claims description 4
- 239000004033 plastic Substances 0.000 claims description 3
- 239000000047 product Substances 0.000 description 19
- 239000002245 particle Substances 0.000 description 12
- 239000010419 fine particle Substances 0.000 description 11
- 238000004519 manufacturing process Methods 0.000 description 11
- 238000011160 research Methods 0.000 description 11
- 230000009286 beneficial effect Effects 0.000 description 10
- 238000013461 design Methods 0.000 description 10
- 230000008569 process Effects 0.000 description 9
- 239000011362 coarse particle Substances 0.000 description 8
- 238000005457 optimization Methods 0.000 description 8
- 238000005265 energy consumption Methods 0.000 description 6
- 230000033001 locomotion Effects 0.000 description 5
- 230000000694 effects Effects 0.000 description 4
- 230000006872 improvement Effects 0.000 description 4
- 239000006148 magnetic separator Substances 0.000 description 4
- 229910000831 Steel Inorganic materials 0.000 description 3
- 230000009471 action Effects 0.000 description 3
- 230000007547 defect Effects 0.000 description 3
- 238000005516 engineering process Methods 0.000 description 3
- 229910052500 inorganic mineral Inorganic materials 0.000 description 3
- 239000007788 liquid Substances 0.000 description 3
- 238000007885 magnetic separation Methods 0.000 description 3
- 239000011707 mineral Substances 0.000 description 3
- 238000005065 mining Methods 0.000 description 3
- 238000012545 processing Methods 0.000 description 3
- 238000000926 separation method Methods 0.000 description 3
- 239000010959 steel Substances 0.000 description 3
- 230000008901 benefit Effects 0.000 description 2
- 230000008859 change Effects 0.000 description 2
- 125000004122 cyclic group Chemical group 0.000 description 2
- 238000002474 experimental method Methods 0.000 description 2
- 230000005484 gravity Effects 0.000 description 2
- 238000013178 mathematical model Methods 0.000 description 2
- JTJMJGYZQZDUJJ-UHFFFAOYSA-N phencyclidine Chemical class C1CCCCN1C1(C=2C=CC=CC=2)CCCCC1 JTJMJGYZQZDUJJ-UHFFFAOYSA-N 0.000 description 2
- 238000012360 testing method Methods 0.000 description 2
- 230000008719 thickening Effects 0.000 description 2
- XLYOFNOQVPJJNP-UHFFFAOYSA-N water Substances O XLYOFNOQVPJJNP-UHFFFAOYSA-N 0.000 description 2
- 238000009825 accumulation Methods 0.000 description 1
- 230000033228 biological regulation Effects 0.000 description 1
- 229910052799 carbon Inorganic materials 0.000 description 1
- 238000010586 diagram Methods 0.000 description 1
- 238000004134 energy conservation Methods 0.000 description 1
- 239000012467 final product Substances 0.000 description 1
- 238000005194 fractionation Methods 0.000 description 1
- 230000014759 maintenance of location Effects 0.000 description 1
- 239000000203 mixture Substances 0.000 description 1
- 230000008520 organization Effects 0.000 description 1
- 230000002093 peripheral effect Effects 0.000 description 1
- 238000001556 precipitation Methods 0.000 description 1
- 230000002035 prolonged effect Effects 0.000 description 1
- 239000002994 raw material Substances 0.000 description 1
- 238000011084 recovery Methods 0.000 description 1
- 230000009467 reduction Effects 0.000 description 1
- 230000000717 retained effect Effects 0.000 description 1
- 239000007787 solid Substances 0.000 description 1
- 239000013589 supplement Substances 0.000 description 1
Images
Classifications
-
- B—PERFORMING OPERATIONS; TRANSPORTING
- B04—CENTRIFUGAL APPARATUS OR MACHINES FOR CARRYING-OUT PHYSICAL OR CHEMICAL PROCESSES
- B04C—APPARATUS USING FREE VORTEX FLOW, e.g. CYCLONES
- B04C5/00—Apparatus in which the axial direction of the vortex is reversed
- B04C5/02—Construction of inlets by which the vortex flow is generated, e.g. tangential admission, the fluid flow being forced to follow a downward path by spirally wound bulkheads, or with slightly downwardly-directed tangential admission
- B04C5/04—Tangential inlets
-
- B—PERFORMING OPERATIONS; TRANSPORTING
- B04—CENTRIFUGAL APPARATUS OR MACHINES FOR CARRYING-OUT PHYSICAL OR CHEMICAL PROCESSES
- B04C—APPARATUS USING FREE VORTEX FLOW, e.g. CYCLONES
- B04C5/00—Apparatus in which the axial direction of the vortex is reversed
- B04C5/08—Vortex chamber constructions
- B04C5/081—Shapes or dimensions
-
- B—PERFORMING OPERATIONS; TRANSPORTING
- B04—CENTRIFUGAL APPARATUS OR MACHINES FOR CARRYING-OUT PHYSICAL OR CHEMICAL PROCESSES
- B04C—APPARATUS USING FREE VORTEX FLOW, e.g. CYCLONES
- B04C5/00—Apparatus in which the axial direction of the vortex is reversed
- B04C5/12—Construction of the overflow ducting, e.g. diffusing or spiral exits
-
- B—PERFORMING OPERATIONS; TRANSPORTING
- B04—CENTRIFUGAL APPARATUS OR MACHINES FOR CARRYING-OUT PHYSICAL OR CHEMICAL PROCESSES
- B04C—APPARATUS USING FREE VORTEX FLOW, e.g. CYCLONES
- B04C5/00—Apparatus in which the axial direction of the vortex is reversed
- B04C5/14—Construction of the underflow ducting; Apex constructions; Discharge arrangements ; discharge through sidewall provided with a few slits or perforations
Landscapes
- Physics & Mathematics (AREA)
- Fluid Mechanics (AREA)
- Geometry (AREA)
- Separation Of Solids By Using Liquids Or Pneumatic Power (AREA)
- Cyclones (AREA)
Abstract
The invention discloses a method for improving the classification efficiency of swirler iron ore pulp, which comprises the following steps: by researching and designing the technical parameters of the swirler, the optimal combination of an ore feeding pipe, an overflow pipe, the diameter of a sand setting nozzle, the cone angle of the swirler, ore feeding pressure, ore feeding granularity, ore feeding concentration, a mode and the like is obtained. The cyclone classification efficiency is improved, the grinding circulation load is reduced, the grinding efficiency of the ball mill is improved, the qualification rate of the product of the secondary grinding iron ore powder with the granularity of 0-0.074 mm is improved by 74.80% from the original 60.73%, the qualification rate is improved by more than 14%, and the secondary grinding efficiency of the ball mill is improved by 11%, so that the foundation is laid for the enterprise to save the grinding power consumption, increase the yield of the iron ore powder and improve the grinding efficiency and the quality of the iron ore powder. Has strong practicability and operability.
Description
Technical Field
The invention relates to a method for improving the grading efficiency of hydrocyclone iron ore slurry, belonging to the field of mine iron ore slurry grading equipment.
Background
The Bixian county mining industry company Limited is a main raw material (iron ore powder) production base of Taiyuan iron and steel (group) company Limited, and the cyclone is main grain size grading equipment after ore grinding for producing the iron ore powder, and the cyclone is used for grinding and grading 870 million tons of iron ore every year. The method comprises the following steps of carrying out secondary grinding and grading on iron ore by using 10 (phi 500mm multiplied by 6 groups/2, phi 500mm multiplied by 4 groups/4, phi 500 mm-GT multiplied by 5 groups/2 and phi 500mm multiplied by 5 groups/2) cyclones, returning iron ore powder products with unqualified particle sizes to a ball mill for regrinding, and conveying iron ore powder with qualified particle sizes to a next-process magnetic separator for magnetic separation. In the production of the past years, the classification efficiency of the cyclone is low, particularly, qualified fine-grained iron ore powder products in sand setting products of the cyclone are returned to the ball mill for regrinding, the iron ore powder is over-ground and becomes argillaceous, meanwhile, the overflow products convey coarse-grained iron ore powder with unqualified granularity to a next procedure magnetic separator for magnetic separation, the problems of serious blockage and serious tail flicking are caused, the ore recovery rate is reduced, the production efficiency of the iron ore powder is seriously influenced, the circulating load of the ball mill is increased, the classification efficiency is reduced, and the like are always difficult to solve, and great difficulty is brought to equipment management and production organization.
The classification principle of the cyclone is that iron ore pulp is fed to the cyclone through a tangential feeding pipe under certain pressure, so that a rotary flow is formed in the cyclone, the rotary speed of the ore pulp reaches the maximum at the center of the cyclone, and the generated centrifugal force is also the maximum. As a result of the expanding movement of the slurry to the surroundings, a low pressure zone is formed around the central shaft. Air is sucked through the sand setting nozzle, and a low-pressure air column is formed at the central shaft. The centrifugal force acting on the ore particles in the cyclone is proportional to the mass of the ore particles, so that the ore particles can be classified according to the size of the iron ore particles when the density of the ore particles is close.
The cyclone structure is mainly formed by connecting a hollow cylinder and a cone, an overflow pipe is inserted into the center of the cylinder, an ore feeding pipe is connected along the tangential direction, and a sand setting nozzle is reserved at the lower part of the cone. The ore pulp is fed into the cyclone along the feeding pipe under the action of pressure, the ore pulp has tangential rotary motion and inward radial motion in the cyclone, the ore pulp close to the center moves upwards (overflow pipe) along the axial direction, and the peripheral ore pulp mainly moves downwards (sand setting nozzle), so that the ore pulp belongs to three-dimensional space motion. The axial ore pulp has a zero-speed point with a direction change, each point is connected to form an approximately conical zero-speed surface (also called a zero-speed envelope surface) in space, the centrifugal settling speed of fine particles is low, the fine particles are pushed into the zero-speed surface by centripetal liquid flow and are discharged by an overflow pipe to form overflow product fine particles; the coarse particles are retained outside the zero-speed surface by the action of larger centrifugal force and are finally discharged by a sand setting nozzle to form coarse particles of a precipitation product. The zero-velocity face position determines the classification granularity.
The cyclone is classification equipment after grinding iron ore and is clearance equipment which finally enters a magnetic separator, but the cyclone often has the problems of high cyclic load, non-uniform stress, low ore grinding efficiency, high energy consumption, high machine vibration, coarse sorting granularity and the like in the production process due to low classification efficiency, multiple machine faults and non-uniform load, so that the technical problem which is difficult to solve is always solved, the ore grinding cost is high, the operation difficulty is high, and the process is complex.
The defects of the original cyclone classification are as follows: the cyclone classification is an important process for sorting the iron ore, and the cyclone is also a throat device of an ore grinding system of the company, is a granularity control device for the iron ore entering the sorting system, and is a key device for judging whether the whole system can carry out on-time production and finishing the handling capacity of 870 ten thousand tons of ores. The cyclone often has the technical problems of low grading efficiency, high circulating load of the ball mill, coarse sorting granularity and the like in the production process, and the problems of high ore grinding cost, high operation difficulty, complex process and the like are always difficult to solve. Therefore, for years, the method continuously explores and repeatedly tracks the conditions of the classification efficiency of the cyclone, the diameter of an ore feeding pipe, the diameter of an overflow pipe, the diameter of a sand setting nozzle, the cone angle of the cyclone, the ore feeding pressure, the ore feeding granularity, the ore feeding concentration, the ore feeding mode and the like according to the current situation, calculates the relation between the classification efficiency and the ore feeding pipe, the overflow pipe, the cone angle of the cyclone, the ore feeding pressure, the ore feeding granularity and the like, and analyzes the problems of low classification efficiency and more faults around the aspects of production and use processes and the like.
For this reason, technicians of our company continuously explore and practice repeatedly for many years, repeatedly track conditions such as classification efficiency of a cyclone, ore feeding pipe diameter, overflow pipe diameter, sand setting nozzle diameter, cyclone cone angle, ore feeding pressure, ore feeding granularity, ore feeding concentration and ore feeding mode according to the current situation, calculate the relationship between classification efficiency and ore feeding pipe, overflow pipe, sand setting nozzle diameter, cyclone cone angle, ore feeding pressure and ore feeding granularity, and repeatedly compare the classification efficiency and ore feeding pipe diameter, overflow pipe, sand setting nozzle diameter, cyclone cone angle, ore feeding pressure and ore feeding granularity in combination with the on-site regulation condition of workers; meanwhile, the reasons of low grading efficiency, high circulation load and coarse grading particle size of the cyclone are analyzed in the aspects of production and use processes, and a safe, economic, simple, convenient and efficient grading technology for the cyclone is innovatively designed, namely a method for improving the grading efficiency of the cyclone iron ore slurry.
Disclosure of Invention
In order to overcome the defects, the invention aims to provide a method for improving the grading efficiency of the iron ore pulp size of the cyclone, which reduces the circulating load of the ball mill, reduces the blockage of sieve holes, overflow ports and sand setting nozzles, reduces the abrasion of the sand setting nozzles and the overflow ports, reduces the sorting granularity, prolongs the service life of spare parts, reduces the failure rate, improves the utilization coefficient of the ball mill, increases the yield of the iron ore powder and improves the quality of the iron ore powder.
The invention is suitable for all swirler iron ore pulp size grading systems, such as swirler iron ore pulp grading systems with the diameter phi of 300-phi 900mm, is particularly suitable for swirler grading systems with the diameter phi of 500mm (1-6) groups and 450mm (1-6) groups, improves the swirler grading efficiency, reduces the circulating load of an ore grinding system, prolongs the service life of an overflow port, a sand setting nozzle and the like, reduces the replacement frequency of the inner lining of the swirler, reduces the consumption of steel balls and energy sources of grinding media of a ball mill, and has great popularization value; the invention adopts the design idea of grading yield, ore grinding power consumption and mineral sorting theory and innovatively designs the diameter of an ore feeding pipe of the cyclone, the diameter of an overflow pipe, the diameter of a sand setting nozzle, the cone angle of the cyclone, ore feeding pressure, ore feeding granularity, ore feeding concentration, an ore feeding mode and the like. The grading stability of the cyclone is improved, and a mathematical model test is designed to find the optimum ore feeding pipe, overflow pipe, sand setting nozzle diameter, cone angle, ore feeding pressure, ore feeding granularity, ore feeding concentration, ore feeding mode and the like of the cyclone.
The invention provides a method for improving the grading efficiency of a swirler (iron ore pulp), in particular to a method for improving the grinding and grading efficiency of an iron ore secondary ball mill.
The specific operation is described as follows:
(1) the feeding mode is designed into a spiral involute feeding mode
The design is given the ore deposit mode for the spiral involute shape, realizes the spiral involute and feeds the ore deposit, reduces and gives the regional area of ore deposit swirl and turbulent flow, improves classification efficiency, and research shows: the inner diameter of the ore feeding pipe of the cyclone is improved from the original tangent-shaped ore feeding to the spiral involute-shaped ore feeding, so that a spiral involute-shaped ore feeding mode is realized, the area of an ore feeding vortex and a turbulent flow area is reduced, the technical problems that the iron ore slurry is easy to enter the cyclone and impacts with the wall of the cyclone to generate local vortex and turbulent flow, the grading efficiency is influenced, the product granularity is easy to mix and the like in the original ore feeding mode are solved, and the separation efficiency is improved; the inner diameter of the ore feeding pipe is in a proportional relation with the processing capacity, the separation granularity and the classification efficiency.
(2) Increasing the inner diameter of the overflow pipe from phi 130-phi 150mm to phi 170-phi 190 mm. The research shows that: the inner diameter of the overflow pipe is increased, the overflow amount is increased, the granularity of an overflow product becomes coarse, the fine particle grade in a sand setting product is reduced, the sand setting concentration is increased, and the grading efficiency can be improved.
(3) The insertion depth of the overflow pipe is improved, and the insertion depth of the overflow pipe is increased from 300-350 mm to 430-450 mm. The research shows that: increase overflow pipe insertion length, overflow product granularity adds roughly, otherwise reduces overflow pipe insertion length, and overflow product granularity also adds roughly, consequently selects the overflow pipe depth of insertion appropriately, can improve classification efficiency, stabilizes the iron ore thick liquid classification granularity.
(4) Reducing the height of a cylinder of the cyclone, wherein the height of the cylinder is set to be (0.5-0.8) D from the original (1.0-2.0) D, and D is the diameter of the cylinder; the cylinder height is set up to 300 ~ 400mm by original 600 ~ 800 mm. The research shows that: the height of the cylinder of the swirler is reduced, the retention time of iron ore pulp in the swirler is reduced, the abrasion of the iron ore pulp to the swirler body is reduced, otherwise, the length of the cylinder of the swirler is increased, the abrasion of the iron ore pulp to the swirler body is increased, the length of the cylinder of the swirler is properly selected, the classification efficiency can be improved, and the abrasion of the iron ore pulp to the swirler body is reduced.
(5) The diameter of the sand setting nozzle is increased, and the sand setting nozzle is designed to be phi 70-phi 90mm from the original phi 40-phi 60 mm. The research shows that: the diameter of the sand setting nozzle is always in a certain proportional relation with the diameter of the overflow pipe, and the ratio of the diameter of the sand setting nozzle to the diameter of the overflow pipe
Called pyramid ratio (d)ovIs the inner diameter of the overflow pipe, dsThe inner diameter of the sand setting nozzle). Experiments show that the pyramid ratio is preferably 2-4, and the pyramid ratio is an effective means for changing the classification granularity. The inner diameter of the sand setting nozzle is increased, so that the overflow fineness can be improved; the sand setting nozzle is the most easily worn part in the cyclone, and the inner diameter of the sand setting nozzle is increased to increase the area of a discharge port, so that the sand setting yield is increased, and the sand setting concentration is reduced. If the sand setting nozzle is too small, the coarse particles are more accumulated on the conical top, and the sand setting nozzle is blocked. The change of the size of the sand setting nozzle has little influence on the treatment capacity of the cyclone, but has influence on the classification efficiency.
(6) The cone angle of the cyclone is increased, and the cone angle of the sand setting nozzle is designed to be 21-25 degrees from the original 10-15 degrees. The research shows that: the size of the cone angle of the grit nozzle influences the resistance to downward flow of the iron ore slurry and the height of the graded free surface. Generally, the cyclone for classifying fine particles adopts a small cone angle, and the minimum angle is 10-15 degrees; the cyclone for coarse particle classification adopts a large cone angle which reaches 21-45 degrees.
(7) The feeding pressure of the swirler is reduced from 0.20MPa to 0.30MPa to 0.07MPa to 0.15MPa, and research shows that: the driving power and abrasion of a slurry pump can be greatly reduced by properly reducing the feeding pressure, the kinetic energy consumption is reduced, and the abrasion of a sand setting nozzle is reduced, so that the feeding pressure is an important parameter for the operation of a swirler, the feeding pressure is improved, the flow velocity of ore pulp is increased, and the grading efficiency and the sand setting concentration can be improved; tests show that the effect of reducing the grading granularity by increasing the pressure is little, the kinetic energy consumption of a slurry pump is greatly increased, and the abrasion of a swirler, particularly a sand setting nozzle, is more serious. Therefore, when coarse-grained iron ore pulp is treated, low-pressure (0.07-0.15 MPa) operation is adopted as far as possible; only when fine particles and argillaceous iron ore pulp are treated, the operation is carried out under a higher pressure (0.20-0.30 MPa);
(8) the design of the slurry pump for direct feeding is that the original pressure stabilizing box for feeding is designed into the design of the slurry pump for direct feeding, and the feeding mode can obtain higher feeding pressure, is convenient to configure, has few pipelines and is convenient to maintain.
(9) The ore feeding concentration of the cyclone is increased, the ore feeding mass concentration is designed to be 40-45% from the original 10-20%, and researches show that: when the size and the pressure of the cyclone are fixed, the ore feeding concentration has important influence on the overflow granularity and the classification efficiency. The feeding concentration is high, the grading granularity becomes coarse, and the grading efficiency is also reduced. When the grading granularity is-0.074 mm (less than 200 meshes), the ore feeding concentration is preferably 40-45%; when the grading granularity is-0.019 mm (less than 800 meshes), the ore feeding concentration is 10-20%.
(10) The ore feeding granularity of the cyclone is improved, the ore feeding granularity of the cyclone is improved from the original ore feeding granularity of more than 20 percent (which means the mass percent) to more than 45 percent (the research shows that: the most important of them is the feed particle size composition (including mud content), when the size and pressure of the cyclone are fixed, the feed particle size content is raised, and then the classification efficiency can be raised.
(11) Increasing the length of the sand setting pipe: connecting a rubber plastic pipe with the diameter of 100mm to the cyclone sand setting nozzle, lengthening the sand setting pipe by 3-5 m, facilitating the discharge of lower-concentration sand setting, adjusting the flow direction of the sand setting, and forming uniform high-concentration accumulation;
(12) the cyclone sand setting nozzle is designed to be inverted cone, the optimum working state of the cyclone for grading is that the sand setting product is sprayed out in umbrella shape, and the center of the umbrella is designed to have an air suction inlet with phi 10-phi 30 mm. This allows air to carry fine particles in the inner slurry out of the overflow as it flows upward, thereby facilitating improved classification efficiency. At the moment, the cone angle of the umbrella is 10-15 degrees. The research shows that: when the cyclone is used for grading, the settled sand is sprayed out in an umbrella shape, so that the grading efficiency can be improved; when the cyclone is used for concentration, the settled sand is discharged in a rope shape, so that the concentration efficiency can be improved, and the settled sand concentration is highest; when the cyclone is used for dewatering, settled sand is discharged in an umbrella shape with the largest angle (the angle is 21-45 degrees), at the moment, the concentration of the settled sand is the lowest, overflow with the least solid content can be correspondingly obtained, and the dewatering efficiency can be improved.
The invention has the beneficial effects that:
(1) the technology capable of improving the classification efficiency of the cyclone provided by the invention adopts the design idea of classification yield, ore grinding power consumption and mineral sorting theory, improves the classification efficiency of the cyclone to the maximum extent, and reduces the ore grinding circulation load and energy consumption of the ball mill. Meanwhile, the defects of low grading efficiency of the original cyclone, large circulating load of the ball mill and the like are overcome.
(2) The technical innovation design advantage of improving the classification efficiency of the cyclone is as follows: the grading efficiency is improved, the circulating load of an ore grinding system is reduced, the service lives of an overflow port, a sand setting nozzle and the like are prolonged, the replacement times of the liner of the cyclone and the like are reduced, and the energy consumption of the ball mill is reduced. Meanwhile, the problems of low grading efficiency, blockage of an overflow pipe, a sand setting nozzle and the like, mixed product granularity, unsmooth ore discharge, multiple machine faults, uneven load, large cyclic load of an original ball mill, uneven stress, low ore grinding efficiency, large machine vibration, coarse grading granularity, poor grading effect and the like of the original cyclone are solved.
(3) In order to improve the grading efficiency after grinding, reduce the grinding circulation load, release the processing capacity of a ball mill during the operation, improve the qualified yield of iron ore powder and improve the economic benefit of the ore, the iron ore pulp grading operation parameters of a cyclone are innovatively set, a mathematical model is established, the optimum combination of the optimum ore feeding pipe, an overflow pipe, a sand setting nozzle, the ore feeding pressure, the ore feeding granularity, the ore feeding concentration and the like of the cyclone is designed and calculated, the beneficial effect is obtained after the implementation, the grading potential of the cyclone is excavated, and the grinding grading circulation load is reduced. After the secondary ball mill grinds the ores, the qualification rate of the iron ore powder product with the granularity of 0-0.074 mm is improved by 74.80% from original 60.73%, the percentage is improved by nearly 14%, meanwhile, the classification efficiency is improved by 13%, and the ore grinding circulation load is reduced by 11.78%, so that the ore grinding classification circulation load is reduced after the design, and the ore grinding yield, the classification efficiency, the iron ore powder yield and the quality are improved.
(4) The method has great significance in the aspects of energy conservation, emission reduction and low-carbon production, and after the technology for improving the classification efficiency of the cyclone is implemented, the ore grinding classification circulating load is reduced by 11.78%, the electric energy consumption of the ball mill is reduced by 3.6%, and the utilization coefficient of the ball mill, the ore grinding yield, the ore grinding efficiency, the iron ore powder yield and the quality are improved.
Drawings
FIG. 1 is a schematic diagram of the operation of a cyclone of the present invention.
In the figure: 1. the device comprises a sand setting nozzle 2, an ore feeding pipe 3, an overflow pipe 4, a cylinder 5, a cone 6 and a central column.
Detailed Description
The present invention is further illustrated by, but is not limited to, the following examples.
Example 1:
as shown in figure 1, the swirler is mainly formed by connecting a hollow cylinder 4 and a cone 5, an overflow pipe 3 is inserted into the center of the cylinder, an overflow port is arranged outside the overflow pipe, an ore feeding pipe 2 is arranged at the top of the swirler along the direction of a spiral involute, and a sand setting nozzle 1 is arranged at the lower part of the cone. Under the action of pressure, the iron ore pulp is fed into the cyclone along the spiral involute feeding pipe 2 and then makes rotary motion under the limitation of the cylindrical wall. The coarse particles are thrown to the wall of the cyclone due to inertial centrifugal force, the coarse particles have large gravity and gradually flow downwards and are discharged from the bottom to form coarse particle sand setting products, the moving speed of the fine particles under the gravity to the wall of the cyclone is lower, and the fine particles are driven by liquid flowing towards the center and are discharged from a central overflow pipe to form fine particle overflow products. Although the cyclone ore-feeding device is simple in structure, the optimum combination of the cyclone ore-feeding pipe, the overflow pipe, the diameter of the sand-setting nozzle, the cone angle of the cyclone, the ore-feeding pressure, the ore-feeding granularity, the ore-feeding concentration and the like greatly influences the grading efficiency of the cyclone; the following examples illustrate the effects of the present invention:
the Taigang Xian county mineral industry Limited company uses 10 (phi 500mm multiplied by 6 group/2, phi 500mm multiplied by 4 group/4, phi 500 mm-GT multiplied by 5 group/2, phi 500mm multiplied by 5 group/2) cyclones to carry out the product classification after the secondary ball mill grinding of the iron ore pulp, coarse particle sand setting returns the unqualified iron ore powder product to the ball mill for regrinding, fine particle overflow conveys the qualified particle size iron ore powder to the magnetic separator for magnetic separation, and the final product is the qualified particle size and the qualified grade iron ore powder.
The device that Bixian county mining industry Limited company used secondary ore grinding is set up to phi 500mm 4 group swirler, and we have carried out optimal design to running parameters such as swirler sand setting nozzle, overflow pipe, for ore pressure, in the middle of the production operation process, have mastered the law that improves the classification efficiency of swirler:
1. the increase of the inner diameter of the sand setting nozzle of the cyclone is not beneficial to the improvement of the classification efficiency, but is beneficial to the improvement of the overflow fineness, the requirement on the classification overflow fineness of secondary ore grinding is considered that the content of 0.074mm is more than 76 percent, and the inner diameter of the sand setting nozzle is set to be 70-90 mm, so that the requirement on the overflow fineness can be met, and the improvement of the classification efficiency is also beneficial.
2. The overflow pipe with the inner diameter phi of 170-190 mm is more beneficial to improving the grading efficiency than the overflow pipe with the diameter phi of 130-150 mm, but the overflow granularity is reduced, the granularity basically meets the process requirement under 0.07-0.15 MPa, and the grading fineness can be improved by properly increasing the pressure.
3. Along with the improvement of ore feeding pressure, the grading efficiency tends to increase, but the grading efficiency is not too high, otherwise, the driving power of a slurry pump is increased, and the abrasion of a pipeline and the like is increased.
4. The cyclone ore feeding concentration has great influence on classification, the classification efficiency is in a descending trend along with the increase of the ore feeding concentration, the overflow granularity is in a thickening trend, the classification efficiency is not lower than 55 percent, and the ore feeding concentration is not more than 50 percent.
The indexes in the research process are compared in the following table 1-7:
TABLE 1 optimization index of sand setting nozzle of cyclone
TABLE 2 optimization index of the sand setting nozzle of the cyclone
TABLE 3 optimization index of sand setting nozzle of cyclone
From the comparison, the cyclone sand setting nozzle is not beneficial to improving the classification efficiency, but is beneficial to improving the overflow fineness, and the sand setting nozzle is 70mm to meet the overflow fineness requirement and be beneficial to improving the classification efficiency by combining the requirement of secondary classification overflow fineness-0.074 mm is more than or equal to 80%.
TABLE 4 swirler overflow tube optimization index
From the comparison, the 170mm overflow pipe is beneficial to improving the grading efficiency compared with the 150mm overflow pipe, but the overflow granularity is reduced, the granularity basically meets the process requirement under 0.1MPa, and the grading fineness can be improved by properly improving the feeding pressure.
TABLE 5 cyclone Ore feeding pressure optimization index
From the above experiments, it can be seen that the fractionation efficiency tends to increase with increasing pressure.
TABLE 6 cyclone ore-feeding concentration optimization index
From the data, the influence of the feeding concentration of the cyclone on the classification is large, the classification efficiency is in a descending trend along with the increase of the feeding concentration, the overflow granularity is in a thickening trend, and the feeding concentration is not more than 50 percent if the classification efficiency is not less than 55 percent.
Table 7 overflow pipe, sand setting nozzle, ore feeding concentration and ore feeding pressure are well matched with experimental result control parameters: 70mm of sand setting nozzle, 170mm of overflow pipe and 0.178MPa of pressure
Two-stage cyclone operation parameter optimization conclusion
The method for improving the classification efficiency of the cyclone by taking the iron ore slurry as a processing object comprises the following steps:
(1) the feeding mode is designed as spiral involute feeding:
the original ore feeding mode of the inner diameter tangent line shape in the ore feeding pipe is set to be the ore feeding mode of the inner diameter spiral involute shape, the spiral involute shape ore feeding mode is realized, the area of an ore feeding vortex and a turbulent flow area is reduced, the technical problems that the ore pulp enters a cyclone and impacts with the wall of the cyclone to generate local vortex to influence the classification efficiency and the product granularity is easy to mix in the original tangent line shape ore feeding mode are solved, and the separation speed and the classification efficiency are improved.
(2) Increasing the inner diameter of an overflow pipe, wherein the inner diameter of the overflow pipe is designed to be phi 170-phi 190 mm; preferably 170 mm;
(3) the insertion depth of the overflow pipe is increased, and the insertion depth of the overflow pipe is designed to be 430-450 mm;
(4) reducing the height of a cylinder of the cyclone, wherein the height of the cylinder is (0.5-0.8) D, and D is the diameter of the cylinder; the height of the cylinder of the cyclone is designed to be 300-400 mm;
(5) increasing the diameter of the sand setting nozzle, wherein the inner diameter of the sand setting nozzle is designed to be phi 70-phi 90 mm; preferably 70 mm;
(6) the cone angle of the cyclone is increased, and the cone angle of the sand setting nozzle is designed to be 21-25 degrees;
(7) reducing the feeding pressure of the swirler to 0.07 MPa-0.15 MPa;
(8) designing a slurry pump to directly feed, and designing the cyclone to directly feed the slurry pump from the original pressure stabilizing box feeding;
(9) the ore feeding concentration of the cyclone is increased, the ore feeding weight concentration is designed to be 40-45%,
(10) the ore feeding granularity of the cyclone is improved, and the ore feeding granularity of the cyclone is improved to be more than 45 percent from the original ore feeding granularity of more than 20 percent (weight percentage) of-0.074 mm;
(11) lengthening a sand setting pipe: connecting a rubber plastic pipe with the diameter of phi 100mm on the cyclone sand setting nozzle, and lengthening a sand setting pipe;
(12) the shape of the sand setting of the cyclone is designed to be umbrella-shaped, and the sand setting is sprayed out in an umbrella-shaped manner; the center of the sand setting umbrella is provided with an air suction inlet with phi 10-phi 30 mm; the cone angle of the umbrella is 21-45 degrees.
The operation requirements are as follows: when the overflow fineness needs to be improved, measures of increasing the pump pool for replenishing water and improving the ore feeding pressure are adopted. After the water supplement amount is increased, the ore feeding amount of the cyclone is increased, and the ore feeding pipe of the cyclone is changed into 125 mm.
The method is tried by Taiyuan iron and steel (group) company, Bin county, mining industry and Limited company, the operating parameters of the cyclone are optimally designed to be 14, and the grading effect is better after the optimization design.
Claims (5)
1. A method for improving the classification efficiency of cyclone iron ore slurry is characterized in that: the method comprises the following steps:
(1) the feeding mode is designed as spiral involute feeding: the feeding mode of the inner diameter tangent line shape in the original feeding pipe is set to be the feeding mode of the inner diameter spiral involute shape, so that the spiral involute shape feeding mode is realized;
(2) increasing the diameter of the inner diameter of the overflow pipe, wherein the inner diameter of the overflow pipe is set to phi 170-phi 190 mm;
(3) the insertion depth of the overflow pipe is increased, and the insertion depth of the overflow pipe is set to be 430-450 mm;
(4) reducing the height of a cylinder of the cyclone, wherein the height of the cylinder is set to be (0.5-0.8) D, and D is the diameter of the cylinder;
(5) increasing the diameter of the sand setting nozzle, wherein the inner diameter of the sand setting nozzle is set to be phi 70-phi 90 mm;
(6) increasing the length of the sand setting pipe, connecting a rubber plastic pipe with the diameter of phi 100-phi 120mm on the sand setting nozzle of the cyclone, and lengthening by 3-5 m;
(7) reducing the feeding pressure of the cyclone, wherein the feeding pressure is set to be 0.07-0.15 MPa;
(8) the method is characterized in that a slurry pump is designed to directly feed, the swirler feed is designed to be the slurry pump from the original pressure stabilizing box feed, and the resistance of a pipeline and the pressure stabilizing box is reduced, so that higher feed pressure is obtained, and the abrasion to the slurry pump and the pipeline is reduced;
(9) the ore feeding concentration of the cyclone is increased, the ore feeding weight concentration is set to be 40-45%,
(10) the ore feeding granularity of the cyclone is improved, and the ore feeding granularity of the cyclone is improved to be more than 45 percent from the original ore feeding granularity of more than 20 percent by weight and 0.074 mm;
(11) the cone angle of the cyclone is increased, and the inner diameter cone angle of the sand setting nozzle is designed to be 21-25 degrees;
(12) the shape of the sand setting nozzle of the cyclone is set to be inverted cone shape, and the grading efficiency is best when the sand setting nozzle is sprayed out in umbrella surface shape.
2. The method for improving the classification efficiency of hydrocyclone iron ore slurries according to claim 1, characterized in that: the height of the cylinder of the cyclone is designed to be 300-400 mm.
3. The method for improving the classification efficiency of hydrocyclone iron ore slurries according to claim 1, characterized in that: the diameter of the sand setting nozzle and the diameter of the overflow pipe are in a certain proportional relation, and the ratio of the diameter of the sand setting nozzle to the diameter of the overflow pipe
Called pyramid ratio, where dovIs the inner diameter of the overflow pipe, dsThe inner diameter of the sand setting nozzle; the pyramid ratio is 2-4.
4. The method for improving the classification efficiency of hydrocyclone iron ore slurries according to claim 1, characterized in that: the settled sand is sprayed out in an umbrella surface shape, an air suction hole with phi 10-phi 30mm is arranged at the center of the umbrella, and an air suction port with phi 10-phi 30mm is arranged at the center of the umbrella; the cone angle of the umbrella is 21-45 degrees.
5. The method for improving the classification efficiency of hydrocyclone iron ore slurries according to claim 1, characterized in that: the grading efficiency of the cyclone is improved, the grinding circulation load is reduced, the grinding efficiency of the ball mill is improved, the qualification rate of the secondary grinding iron ore powder product with the granularity of 0-0.074 mm can reach 74.80%, and the secondary grinding efficiency is improved by 11%.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202011359824.XA CN112619910A (en) | 2020-11-27 | 2020-11-27 | Method for improving classification efficiency of cyclone iron ore slurry |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202011359824.XA CN112619910A (en) | 2020-11-27 | 2020-11-27 | Method for improving classification efficiency of cyclone iron ore slurry |
Publications (1)
| Publication Number | Publication Date |
|---|---|
| CN112619910A true CN112619910A (en) | 2021-04-09 |
Family
ID=75306631
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CN202011359824.XA Pending CN112619910A (en) | 2020-11-27 | 2020-11-27 | Method for improving classification efficiency of cyclone iron ore slurry |
Country Status (1)
| Country | Link |
|---|---|
| CN (1) | CN112619910A (en) |
Citations (6)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN2590660Y (en) * | 2002-12-20 | 2003-12-10 | 昆明冶金研究院 | Water-sealed swirler |
| WO2008067702A1 (en) * | 2006-12-08 | 2008-06-12 | Bin Li | Ore slurry cyclonic flotation method, cyclone flotation column and flotation apparatus therefor |
| CN102228873A (en) * | 2010-07-30 | 2011-11-02 | 鞍钢集团矿业公司 | Autoalarm of overflow particle size coarse of primary classifying hydrocyclone |
| CN105562184A (en) * | 2015-12-21 | 2016-05-11 | 云南磷化集团有限公司 | Method and equipment for improving grinding efficiency and classifying efficiency by rough grinding and rough classifying |
| CN205966200U (en) * | 2016-08-25 | 2017-02-22 | 北京中选耐磨设备有限公司平顶山分公司 | Flat swirler of adjustable |
| CN206325720U (en) * | 2016-11-10 | 2017-07-14 | 北京金诚信矿山技术研究院有限公司 | A kind of tailings cyclone classification experimental system |
-
2020
- 2020-11-27 CN CN202011359824.XA patent/CN112619910A/en active Pending
Patent Citations (6)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN2590660Y (en) * | 2002-12-20 | 2003-12-10 | 昆明冶金研究院 | Water-sealed swirler |
| WO2008067702A1 (en) * | 2006-12-08 | 2008-06-12 | Bin Li | Ore slurry cyclonic flotation method, cyclone flotation column and flotation apparatus therefor |
| CN102228873A (en) * | 2010-07-30 | 2011-11-02 | 鞍钢集团矿业公司 | Autoalarm of overflow particle size coarse of primary classifying hydrocyclone |
| CN105562184A (en) * | 2015-12-21 | 2016-05-11 | 云南磷化集团有限公司 | Method and equipment for improving grinding efficiency and classifying efficiency by rough grinding and rough classifying |
| CN205966200U (en) * | 2016-08-25 | 2017-02-22 | 北京中选耐磨设备有限公司平顶山分公司 | Flat swirler of adjustable |
| CN206325720U (en) * | 2016-11-10 | 2017-07-14 | 北京金诚信矿山技术研究院有限公司 | A kind of tailings cyclone classification experimental system |
Non-Patent Citations (4)
| Title |
|---|
| 孙传尧: "《选矿工程师手册》", 31 March 2015 * |
| 孙玉波: "《重力选矿》", 31 July 1982 * |
| 张泾生: "《现代选矿技术手册》", 31 March 2016 * |
| 王泽红: "《选矿数学模型》", 28 February 2015 * |
Similar Documents
| Publication | Publication Date | Title |
|---|---|---|
| CN106925436B (en) | Tapered centrifugal ore dressing equipment | |
| AU2011229688A1 (en) | Preparation method for ultra low ash coal-water slurry | |
| CN106964480B (en) | A kind of fine grinding sorted suitable for micro fine particle magnetite stone-hierarchical composition new process | |
| WO2021203752A1 (en) | Method for improving grinding and classification capacity by reducing sand deposition fineness ratio value | |
| US20220314233A1 (en) | Underground coal hypergravity field separation system and separation process | |
| CN103240160B (en) | Ore pulp grading plant | |
| CN110882851B (en) | Beneficiation system and beneficiation method for sulfide ore | |
| CN106311453A (en) | Device for closed cycle phosphorite wet ball grinding and ball grinding method | |
| CN206688887U (en) | A kind of fine grinding hierarchical composition device systems sorted for micro fine particle magnetite stone | |
| CN107127045B (en) | Inside self classification device of vertical spiral stirring mill | |
| CN212418290U (en) | Improved composite force mineral processing equipment | |
| CN205587170U (en) | Novel swirler pottery sand settling nozzle | |
| CN112619910A (en) | Method for improving classification efficiency of cyclone iron ore slurry | |
| CN105642408A (en) | Novel vertical roll mill with grinded powder outward-guide mechanism | |
| CN105170283A (en) | Ore grinding grading system and method capable of controlling derichment of iron minerals | |
| CN212120417U (en) | A hydrocyclone that is used for vanadium titano-magnetite to carry out production | |
| CN201064775Y (en) | Separator | |
| CN212263542U (en) | Sorting device for wet-method sorting of petroleum fracturing sand | |
| CN108405135B (en) | Efficient mud and powder removing and particle shape optimizing method and device for tailing sand | |
| CN112452564B (en) | Novel hydrocyclone with secondary pressurization function | |
| CN210357530U (en) | Fluorite associated ore non-pressure three-product heavy medium cyclone | |
| CN206763155U (en) | A kind of sharp miniature centrifugal beneficiating equipment | |
| CN207430512U (en) | A kind of more chopping fine mill short route ore-sorting system structures | |
| RU2465056C1 (en) | Ore suspension separation complex | |
| CN111632751A (en) | Improved composite force mineral processing equipment |
Legal Events
| Date | Code | Title | Description |
|---|---|---|---|
| PB01 | Publication | ||
| PB01 | Publication | ||
| SE01 | Entry into force of request for substantive examination | ||
| SE01 | Entry into force of request for substantive examination | ||
| RJ01 | Rejection of invention patent application after publication |
Application publication date: 20210409 |
|
| RJ01 | Rejection of invention patent application after publication |