Ultra-lean magnetite crushing process based on high-pressure roller mill and vertical roller mill
By combining the crushing processes of high-pressure roller mills and vertical roller mills, and integrating V-type air classifiers and drum magnetic separators, the wear and clogging problems of vertical roller mills in processing ultra-lean magnetite have been solved, resulting in reduced energy consumption and improved processing efficiency.
Patent Information
- Authority / Receiving Office
- CN · China
- Patent Type
- Applications(China)
- Current Assignee / Owner
- Filing Date
- 2025-12-11
- Publication Date
- 2026-03-17
AI Technical Summary
In the existing technology, vertical roller mills suffer from severe wear and are prone to clogging when processing ultra-lean magnetite, resulting in high energy consumption and difficulty in meeting the beneficiation requirements.
The crushing process combines high-pressure roller mills and vertical roller mills, with a V-type classifier replacing the separator. Two-stage dry magnetic separation is used to reduce repeated crushing of tailings. The layering theory is used to reduce the hardness of the ore, and vibrating screens and drum magnetic separators are used for screening and magnetic separation.
It effectively reduces wear and clogging problems in vertical roller mills, reduces energy consumption, improves processing efficiency, and meets the beneficiation requirements of ultra-lean magnetite.
Smart Images
Figure CN121669382A_ABST
Abstract
Description
TECHNICAL FIELD
[0001] The application belongs to the technical field of ultra-lean magnetite processing and beneficiation, and particularly provides an ultra-lean magnetite crushing process based on a high-pressure roller mill and a vertical roller mill. BACKGROUND
[0002] Beneficiation of ores requires the ores to reach a degree of single dissociation, and a crusher and a ball mill are usually used to process the ores to meet the beneficiation requirements. Generally, the ores are first crushed to about 10 mm by a crusher and then fed into a ball mill for grinding. For magnetite, the product particle size of the grinding is usually about 0.1 mm, and in this process, the energy consumption of the ball mill is extremely high. Under the current industrial transformation background of energy saving and emission reduction, the industry is actively developing improved processes.
[0003] The vertical roller mill is usually applied in the non-metal industry, and the particle size of the processed ores can reach 0.1 mm, which can meet the requirements of ultra-lean magnetite beneficiation, and the energy consumption is much lower than that of the ball mill. However, the Protodyakonov hardness of ultra-lean magnetite is much higher than that of non-metallic ores, and the vertical roller mill is not suitable for processing ores with high hardness, and the wear is more serious. In addition, the supporting separator of the vertical roller mill is also difficult to adapt to the processing of ultra-lean magnetite, and is prone to blockage, causing production accidents. SUMMARY
[0004] To solve the above technical problems, the technical scheme adopted by the application is: an ultra-lean magnetite crushing process based on a high-pressure roller mill and a vertical roller mill, and the specific steps are as follows: Step one, ultra-fine crushing; The high-pressure roller mill is used to crush the ores, and the crushed materials enter the next process; Step two, screening; The screened materials return to the high-pressure roller mill, and the ultra-fine crushing process of step one is repeated; The screened materials enter the next process; Step three, large particle size dry magnetic separation; The tailings are transported to the dump for storage; The selected concentrate enters the next process; Step four, powder making; The vertical roller mill is used to crush the materials for the second time, and the crushed materials enter the next process; Step five, air classification; The V-type powder separator is used to classify the crushed materials; The coarse particles enter step six for wet magnetic separation; The fine particles enter step seven for small particle size dry magnetic separation; The V-type powder concentrator is a static classification and scattering device, which can scatter the cake-shaped material output by the roller pressing device, and separate the qualified fine powder in the scattered material; Considering that the state of the coarse particle set is a solid single state, the dry magnetic separation can be directly performed in the drum magnetic separator; The fine particle set is a gas-solid two-phase flow state, which is convenient for slurry treatment; Step six, wet magnetic separation; First, the feed is treated by slurry treatment, and then wet magnetic separation is performed; The concentrate enters the subsequent process treatment; The tailings enter the tailings pond for storage; Step seven, small particle size dry magnetic separation; The concentrate returns to the vertical roller mill, and the processing of steps four and subsequent processes is repeated; The tailings are transported to the dump for storage.
[0005] Further, the screening process in step two is performed by a vibrating screen.
[0006] Further, the dry magnetic separation operation in steps three and seven is performed by a drum magnetic separator.
[0007] Further, the wet magnetic separation operation in step six is performed by a drum magnetic separator.
[0008] Further, in step two, the undersize material of the screening has a particle size of-3mm.
[0009] Further, the crushing particle size of the vertical roller mill 4 is-0.1mm.
[0010] The beneficial effects of using the present application are: A super lean magnetite crushing process based on the cooperation of a high-pressure roller mill and a vertical roller mill is provided; The principle of crushing by the high-pressure roller mill is based on the laminated theory. During the crushing process of the ore, micro cracks will appear in the ore. The Protodyakonov hardness coefficient is closely related to the internal cracks of the ore. As the cracks increase, the Protodyakonov hardness coefficient of the ore will decrease. The super lean magnetite processed by the high-pressure roller mill is fed into the vertical roller mill for processing, which greatly reduces the wear and tear of the machine and solves the problem of the applicability of the vertical roller mill in processing super lean magnetite due to the excessive Protodyakonov hardness of the ore.
[0011] At the same time, the conventional separator matched with the vertical roller mill is abandoned, and a V-type powder concentrator is used as a replacement device, which can effectively prevent the clogging problem.
[0012] Adopt two-stage dry magnetic separation treatment, throw out more tailings in advance, that is, reduce the tailings repeatedly entering the crushing process, further reduce the total energy consumption of the whole process by reducing the crushing amount. BRIEF DESCRIPTION OF DRAWINGS
[0013] Fig. 1 Process flow diagram of the present application; Fig. 2 Device relationship diagram of the present application; Reference signs include: 1, high-pressure roller mill; 2, vibrating screen; 3, first drum magnetic separator; 4, vertical roller mill; 5, V-type powder concentrator; 6, second drum magnetic separator; 7, third drum magnetic separator. DETAILED DESCRIPTION
[0014] The present application will be described in detail below in combination with the drawings.
[0015] Reference Figs. 1-2 , a super lean magnetite crushing process based on a high-pressure roller mill and a vertical roller mill, the specific steps are: Step one, superfine crushing; The high-pressure roller mill 1 is used to crush the ore, and the crushed material enters the next process; Step two, screening; The material on the screen returns to the high-pressure roller mill 1, and the superfine crushing process of step one is repeated; The material under the screen enters the next process; Step three, large particle size dry magnetic separation; The tailings are transported to the dump for storage; The selected concentrate enters the next process; Step four, powder making; The vertical roller mill 4 is used to crush the feed material twice, and the twice crushed material enters the next process; Step five, air classification; The V-type powder concentrator 5 is used to classify the twice crushed material; The coarse particle set enters step six process for wet magnetic separation; The fine particle set enters step seven process for small particle size dry magnetic separation; The V-type powder concentrator 5 is a static classification and scattering device, which can scatter the cake material output by the roller pressure type device, and separate the qualified fine powder in the scattered material; Considering that the state of the coarse particle set is a solid single state (here, what does "single" specifically refer to, it is recommended to make a glossary), it can be directly fed into the drum magnetic separator for dry magnetic separation; The fine particle set is a gas-solid two-phase flow state, which is convenient for slurry treatment; Step six, wet magnetic separation; The feed is first subjected to pulp conditioning, and then wet magnetic separation is performed; The concentrate enters subsequent process treatment; The tailings enter the tailings pond for storage; Step seven, small particle size dry magnetic separation; The concentrate returns to the vertical roller mill 4 for repeated processing of step four and subsequent processes; The tailings are transported to the waste dump for storage.
[0016] Preferably, the screening process in step two is performed using a vibrating screen 2; Dry magnetic separation is performed in steps three and seven using drum magnetic separators; The two drum magnetic separators are a first drum magnetic separator 3 and a second drum magnetic separator 6; The drum magnetic separator in step six is a third drum magnetic separator 7.
[0017] Example one
[0018] This example applies a super lean magnetite crushing process based on a high-pressure roller mill and a vertical roller mill, wherein, In step one, the crushing particle size of the high-pressure roller mill 1 is -3mm; In step two, the undersize material of the screening is -3mm; In step four, the crushing particle size of the vertical roller mill 4 is -0.1mm; In step five, the fine particle collection of the air classification is -0.1mm; In step six, the wet magnetic separation standard is a grade of 40% or higher and a recovery rate of 72% or higher; The feed ore is a super lean magnetite ore with a particle size of -12mm.
[0019] The specific process flow is as follows: The ore is placed in the high-pressure roller mill 1 for crushing treatment; The crushed material is screened, the oversize material is transported back to the high-pressure roller mill 1 for re-crushing treatment, and the undersize material is transported to the subsequent process for large particle size dry magnetic separation; The concentrate from the large particle size dry magnetic separation is transported to the vertical roller mill 4 for secondary crushing, and the tailings are transported to the waste dump for storage; The powder cake is formed after secondary crushing by the vertical roller mill 4; The powder cake enters the V-type powder concentrator 5 and is dispersed and classified, and the fine particle collection and coarse particle collection are separated; The fine particle set is subjected to wet magnetic separation treatment, first slurry is adjusted, and then the ore slurry is separated through the third drum magnetic separator 7, the selected concentrate is the final product of the process, which can be used for subsequent other process treatment, and the tailings are stored in the tailings pond; The coarse particle set is subjected to small particle size dry magnetic separation treatment, the selected concentrate is transported to the vertical roller mill 4, and the secondary crushing treatment is repeated, and the tailings are transported to the dump for storage.
[0020] The above is only a preferred embodiment of the present application, and for those skilled in the art, many changes can be made in the specific implementation and application range according to the idea of the present application, as long as these changes do not deviate from the concept of the present application, and all belong to the protection scope of the present application.
Claims
1. An ultra lean magnetite comminution process based on high pressure roller mill and vertical roller mill characterized by: The specific steps are as follows: Step one, superfine crushing; The ore is crushed by a high-pressure roller mill, and the crushed material enters the next process; Step two, screening; The material on the screen returns to the high-pressure roller mill, and the superfine crushing process of step one is repeated; The material under the screen enters the next process; Step three, large particle size dry magnetic separation; Tailings are transported to the waste dump for storage; The selected concentrate enters the next process; Step four, powder making; A vertical roller mill is used to crush the feed material twice, and the crushed material enters the next process; Step five, air classification; A V-type powder separator is used to classify the crushed material; The coarse particles enter step six for wet magnetic separation; The fine particles enter step seven for small particle size dry magnetic separation; The V-type powder separator is a static classification and dispersion device that can disperse the cake-shaped material output by the roller pressure device and separate the qualified fine powder from the dispersed material; Considering that the coarse particle set is in a solid single state, it can be directly fed into the drum magnetic separator for dry magnetic separation; The fine particle set is in a gas-solid two-phase flow state, which is convenient for slurry treatment; Step six, wet magnetic separation; The feed material is first treated with slurry, and then wet magnetic separation is performed; The concentrate enters the subsequent process; The tailings are stored in the tailings pond; Step seven, small particle size dry magnetic separation; The concentrate returns to the vertical roller mill, and the process of step four and the subsequent processes is repeated; The tailings are transported to the waste dump for storage.
2. A process for crushing ultra lean magnetite based on high pressure roller mill and vertical roller mill as claimed in claim 1 wherein: In step two, a vibrating screen is used to implement the screening process.
3. A process for crushing of ultra lean magnetite based on high pressure roller mill and vertical roller mill as claimed in claim 1, wherein the said process is characterized by: In steps three and seven, a drum magnetic separator is used to implement dry magnetic separation.
4. A process for crushing of ultra lean magnetite based on high pressure roller mill and vertical roller mill as claimed in claim 1, wherein the said process is characterized by: In step six, a drum magnetic separator is used to implement wet magnetic separation.
5. A process for crushing ultra lean magnetite based on high pressure roll mill and vertical roll mill as claimed in claim 1 wherein the said process is characterized by: In step two, the particle size of the material under the screen is -3mm.
6. A process for crushing ultra lean magnetite based on high pressure roller mill and vertical roller mill as claimed in claim 1 wherein: The crushing particle size of the vertical roller mill 4 is -0.1mm.