Crushing system for preparing pellets from rich mineral powder and device for preparing pellets from rich mineral powder
By using a series of carbide pin-roller and smooth roll crushing systems, combined with four-roller crushing, large-particle rich ore powder can be ground to a qualified pelletizing particle size, solving the problem of difficulty in producing qualified pellets in existing technologies and reducing preparation costs.
Patent Information
- Application Number
- CN202520221388.1
- Authority / Receiving Office
- CN · China
- Patent Type
- Utility models(China)
- Current Assignee / Owner
- Filing Date
- 2025-02-12
- Publication Date
- 2025-12-12
- Estimated Expiration
- 2035-02-12
AI Technical Summary
Existing technologies make it difficult to grind large-particle rich ore powder to a qualified pelletizing particle size, resulting in difficulties in producing qualified pellets.
The crushing system employs a series of carbide pin-roller and smooth roll crushing systems, combined with four-roller crushing. It utilizes a specially designed smooth roll structure and a high-torque motor to provide power, achieving multi-stage crushing of rich ore powder until it reaches the qualified particle size.
This method effectively grinds large-particle rich ore powder to a qualified pelletizing particle size, reduces raw material procurement costs, solves the problem of large-particle rich ore powder being difficult to produce qualified pellets, and provides a new approach to pellet preparation process.
Smart Images
Figure CN223655172U_ABST
Abstract
Description
Technical Field
[0001] This utility model relates to the field of pellet preparation technology, specifically to a crushing system for preparing pellets from rich ore powder and a device for preparing pellets from rich ore powder. Background Technology
[0002] Iron pellets, due to their uniform particle size, high iron content, high mechanical strength, and good metallurgical properties, have become an indispensable high-quality furnace charge for blast furnace ironmaking. Pellet production places high demands on the iron concentrate raw materials, typically requiring suitable particle size distribution and specific surface area, low water of crystallization mass fraction, and a reasonable chemical composition. Currently, the main raw material for pellet production is magnetite concentrate. With the rapid development of the steel industry, high-quality and stable magnetite concentrate resources are becoming increasingly scarce. Therefore, developing a technical solution for preparing pellets using rich ore powder can reduce the blending cost of pellet production and broaden the sources of iron concentrate for pellet production.
[0003] Current research on the preparation of pellets from rich mineral powder mainly focuses on the selection, proportioning, and choice of binders for the rich mineral powder, lacking research and improvement on the process flow for preparing pellets from rich mineral powder. Such research lacks comprehensiveness and systematicity, and cannot fundamentally solve the problem that large-particle-size rich mineral powder is difficult to produce qualified pellets.
[0004] Current processes for preparing pellets from rich ore powder typically involve simple grinding of the powder using dry ball mills or high-pressure roller mills, followed by pellet production from the ground powder. However, this simple grinding method only partially addresses the issues of small specific surface area and unqualified particle size. Currently, there is still a lack of methods to fundamentally solve the problem of grinding large-particle rich ore powder to a suitable pelletizing size.
[0005] In summary, new technologies for preparing pellets from rich ore powder still need to be researched to solve the problem of large-particle rich ore powder being difficult to grind to a qualified pelletizing particle size, and to solve the problem of large-particle rich ore powder being difficult to produce qualified pellets. Utility Model Content
[0006] The purpose of this invention is to provide a new technical solution for preparing pellets from rich mineral powder, so as to grind large-particle rich mineral powder to a qualified pelletizing particle size, thereby solving the problem that large-particle rich mineral powder is difficult to produce qualified pellets.
[0007] To achieve the above objectives, this utility model provides the following two technical solutions.
[0008] In one aspect, this utility model provides a crushing system for preparing pellets from rich mineral powder, the system comprising at least four double rollers and at least two four-rollers connected in series.
[0009] The at least four pairs of rollers include at least two carbide pin roller pairs installed first and at least two smooth roller pairs installed later.
[0010] The smooth rollers used in the roller pair are hollow and include a frustum section and a cylindrical section. The cylindrical section is connected to the larger bottom surface of the frustum section. The side surface of the frustum section serves as the grinding surface of the smooth roller. Circular holes with the same size as the crushed particle are opened on the side surface of the frustum section. Circular holes with a diameter larger than the diameter of the circular holes on the side surface of the frustum section are opened on the side surface of the cylindrical section. The circular holes on the side surfaces of the frustum section and the cylindrical section are all connected to the inner cavity of the smooth roller. The smooth roller can make the crushed material fall into the inner cavity of the frustum section of the smooth roller through the circular holes on the side surface of the frustum section, then roll into the inner cavity of the cylindrical section of the smooth roller, and then fall out of the smooth roller through the circular holes on the side surface of the cylindrical section of the smooth roller.
[0011] According to the specific implementation of the first aspect, preferably, the diameter of the circular hole on the side surface of the cylindrical section is more than twice the diameter of the circular hole on the side surface of the frustum section.
[0012] More preferably, the diameter of the circular hole on the side surface of the cylindrical section is twice the diameter of the circular hole on the side surface of the frustum section.
[0013] According to a specific implementation of the first aspect, preferably, the system includes four pairs of rollers connected in series, the four pairs of rollers including two carbide pin roller pairs arranged first and two smooth roller pairs arranged later.
[0014] The first of the two carbide pin roller pairs can crush materials to a diameter of less than A; where A is 4-40 mm.
[0015] The carbide pinned roller pair, with the latter one in the two carbide pinned roller pairs, can crush materials to a diameter of less than B; where B is 2-4mm.
[0016] The first of the two smooth roller pairs can crush materials to a diameter of C or less; where C is 1-2 mm.
[0017] The rear-mounted smooth roller pair of two smooth rollers can crush materials to a diameter of D or less; where D is 0.5-1mm.
[0018] Among them, the diameter of the circular holes on the frustum section side surface of the optical roller of the first optical roller pair is C-sized; the diameter of the circular holes on the frustum section side surface of the optical roller of the second optical roller pair is D-sized.
[0019] More preferably, the system comprises two four-rollers connected in series;
[0020] The first of the two four-roll crushers is capable of crushing materials to a diameter of less than E; where E is 0.1-0.5 mm.
[0021] The rear four rollers of the two four-roll crushers can crush materials to a diameter of less than F; where F is 0.074-0.1mm.
[0022] According to the specific implementation of the first aspect, preferably, the two optical rollers used in each optical roller pair are set on the same horizontal plane, the two optical rollers have the same frustum section structure, and the bottom end of the larger frustum section of each optical roller is flush with the bottom end of the smaller frustum section of the other optical roller, and there is no gap between the grinding surfaces of the two optical rollers.
[0023] This preferred technical solution is more conducive to the concentration of the feed flow, while increasing the crushing time. It provides tangential force while providing lateral crushing force, thus enhancing the crushing effect. Furthermore, it eliminates the need for a gap between the two rollers, ensuring the crushing quality.
[0024] According to the specific implementation plan of the first aspect, preferably, each double-roll crusher and each four-roll crusher are powered by a motor capable of providing a torque of more than 190 N / m in conjunction with a reducer.
[0025] More preferably, the reducer is a DCY500-50 reducer;
[0026] More preferably, the motor is a Y3553-4 motor.
[0027] According to the specific implementation of the first aspect, preferably, the base material of the cemented carbide pin roller is 42CrMo or 40Cr.
[0028] According to the specific implementation of the first aspect, preferably, the base material of the optical roller is 42CrMo or 40Cr.
[0029] The technical method provided in the first aspect can be used to grind rich ore powder in the process of preparing pellets to obtain rich ore pellet powder. The rich ore pellet powder obtained can achieve a mass content of particles with a particle size not exceeding 0.074 mm of not less than 85% (based on the total mass of rich ore pellet powder as 100%).
[0030] Secondly, this utility model provides an apparatus for preparing pellets from rich mineral powder, the apparatus comprising:
[0031] The first aspect provides a crushing system for preparing rich ore powder into pellets, a batching and pelletizing screening system, and a roasting system connected in series.
[0032] According to the specific implementation plan of the second aspect, preferably, the batching, pelletizing and screening system includes a batching chamber, a mixing chamber, a mixed material silo, a briquetting machine and a screening equipment connected in sequence;
[0033] The batching room is equipped with a rich ore pelletizing powder silo and a solid phase binder silo; the mixed material silo is equipped with a liquid phase binder feed port; the briquetting machine is equipped with a water inlet; the feed inlet of the rich ore pelletizing powder silo is connected to the discharge port of the crushing system; the discharge ports of each silo in the batching room are connected to the feed inlet of the mixed material silo.
[0034] More preferably, the batching room is also equipped with a dust removal ash silo; even more preferably, the dust removal ash silo is equipped with a direct-load belt scale, and the dust removal ash silo is equipped with a pressure-type silo top bag filter. The dust removal ash silo is equipped with a weighing level gauge to detect the material level and control the operation of the feeding system; furthermore, the rich ore powder to pellet preparation device also includes an electrostatic precipitator, the material inlet of the electrostatic precipitator is connected to the exhaust gas outlet of the roasting system, and the dust removal ash outlet of the electrostatic precipitator is connected to the dust removal ash silo.
[0035] More preferably, the rich ore pelletizing powder silo is equipped with a frequency-controlled disc feeder and an electronic belt scale, the rich ore pelletizing powder silo is equipped with a pressure-type silo top bag dust collector, and the rich ore pelletizing powder silo is equipped with a weighing level gauge to detect the material level and control the operation of the feeding system.
[0036] More preferably, the solid binder silo is equipped with a direct-drive belt scale, the solid binder silo is equipped with a pressure-type silo top bag dust collector, and the solid binder silo is equipped with a weighing level gauge to detect the material level and control the operation of the feeding system.
[0037] More preferably, the discharge ports of each silo in the batching chamber are connected to the inlet of the mixing silo via a conveyor belt;
[0038] More preferably, the mixing chamber is connected to the mixing silo via a belt conveyor and a plow-type unloader connected to the belt conveyor;
[0039] More preferably, the mixing silo is connected to the briquetting machine via a belt conveyor equipped with a belt scale; wherein, the belt conveyor is equipped with a moisture detector to detect the moisture content of the material being transported by the belt conveyor, thereby controlling the amount of water added to the briquetting machine;
[0040] More preferably, the screening equipment uses a 16mm aperture screen;
[0041] More preferably, each silo in the batching and pelletizing screening system is made of steel and lined with wear-resistant and non-stick material lining plates. The cone section is equipped with a vibrator to prevent material blockage.
[0042] According to the specific implementation plan of the second aspect, preferably, the roasting system includes a chain grate machine, a rotary kiln and an annular cooler connected in series, which enables the material processed by the chain grate machine to fall into the rotary kiln for processing, and the material from the rotary kiln to fall into the annular cooler for processing.
[0043] More preferably, the chain grate machine is sequentially equipped with a material feeding system, a blower drying section, an exhaust drying section, a preheating section I, and a preheating section II;
[0044] More preferably, the material inlet of the chain grate is connected to the material outlet of the batching and pelletizing screening system via a collecting conveyor belt, thereby enabling the material discharged from the batching and pelletizing screening system to be transported to the chain grate by the collecting conveyor belt; even more preferably, a belt scale is installed on the collecting conveyor belt to detect the amount of material being transported by the collecting conveyor belt, which helps to control the material thickness inside the chain grate.
[0045] More preferably, the rotary kiln is equipped with a kiln head hood and a kiln tail hood, and is equipped with a structural cooling fan; the rotary kiln roasts the materials inside the kiln through thermal radiation; the rotary kiln can achieve a roasting temperature of 1250-1280℃.
[0046] More preferably, the annular cooler is provided with a first cooling section, a second cooling section, and a third cooling section in sequence;
[0047] More preferably, the exhaust port of the first cooling section of the ring cooler is connected to the air inlet of the preheating section I of the chain grate machine, thereby realizing the reuse of the reheated air from the first cooling section as a heat source for the preheating section II; in a specific embodiment, the reheated air obtained from the first cooling section is close to 1050-1150°C, and the preheating section II of the chain grate machine uses hot airflow above 1000°C (preferably 1000-1100°C) for preheating;
[0048] More preferably, the exhaust port of the second cooling section of the annular cooler is connected to the air inlet of the preheating section II of the chain grate machine, thereby realizing the reuse of the regenerated air from the second cooling section as a supplementary heat source for the preheating section I; in a specific embodiment, the regenerated air obtained from the second cooling section is at approximately 650-750°C, and the preheating section I of the chain grate machine uses hot airflow at a temperature above 700°C (preferably 700-800°C) for preheating;
[0049] More preferably, the exhaust port of the three cooling sections of the annular cooler is connected to the air inlet of the blower drying section of the chain grate machine, thereby realizing the reuse of the regenerated air from the three cooling sections as a heat source for the blower drying section; in a specific embodiment, the regenerated air at nearly 300-400°C obtained from the three cooling sections is used by the blower drying section of the chain grate machine for blower drying with hot airflow at 300-400°C.
[0050] More preferably, the exhaust port of the preheating section II of the chain grate machine is connected to the air inlet of the exhaust drying section of the chain grate machine, thereby realizing the reuse of the reheated air from the preheating section II as a heat source for the exhaust drying section; in a specific embodiment, the reheated air obtained from the exhaust port of the preheating section II of the chain grate machine is at approximately 400-500°C, and the exhaust drying of the chain grate machine uses the hot airflow at 400-500°C for exhaust drying.
[0051] This invention provides a crushing system for preparing pellets from rich ore powder. It utilizes a special series connection of two rollers and four rollers to crush the rich ore powder, enabling the grinding of large-particle rich ore powder to a suitable pelletizing size. This pelletizing device eliminates the need for drying pretreatment equipment and high-pressure roller mills, effectively replacing iron concentrate with rich ore powder to produce pellets with an FeO content of no more than 1%. This reduces raw material procurement costs, saves construction investment, and solves the problem of producing qualified pellets from large-particle rich ore powder. The technology provided by this invention offers a new direction and new ideas for the development of the pelletizing industry. Attached Figure Description
[0052] Figure 1 This is a schematic diagram of the crushing system for preparing pellets from rich ore powder in Example 1.
[0053] Figure 2 This is a schematic diagram of the structure of the optical roller in Example 1.
[0054] Figure 3 This is a schematic diagram of the apparatus for preparing pellets from rich ore powder in Example 2. Detailed Implementation
[0055] In order to provide a clearer understanding of the technical features, objectives and beneficial effects of this utility model, the technical solution of this utility model is described in detail below, but it should not be construed as limiting the scope of implementation of this utility model.
[0056] Example 1
[0057] This embodiment provides a crushing system for preparing pellets from rich mineral powder.
[0058] like Figure 1 As shown, the system includes: a first pair of carbide pin rollers 11, a second pair of carbide pin rollers 12, a first pair of smooth rollers 13, a second pair of smooth rollers 14, a first four-roller 15, and a second four-roller 16 connected in series.
[0059] like Figure 2 As shown, the first optical roller 13 uses a hollow structure, i.e., it has an inner cavity (inner cavity). Figure 2(Not shown in the image) and includes a frustum section 131 and a cylindrical section 132. The cylindrical section 132 is connected to the larger bottom surface of the frustum section 131. The side surface of the frustum section 131 serves as the grinding surface of the smooth roller. Circular holes 1311 with the same crushing particle size are opened on the side surface of the frustum section 131. Circular holes 1321 with a diameter twice that of the circular holes 1321 on the side surface of the frustum section 131 are opened on the side surface of the cylindrical section 132. The circular holes 1311 on the side surface of the frustum section 131 and the circular holes 1322 on the side surface of the cylindrical section 132 are both connected to the inner cavity of the smooth roller. The smooth roller enables the crushed material to fall into the inner cavity of the frustum section 131 through the circular holes 1311 on the side surface of the frustum section 131, then roll into the inner cavity of the cylindrical section 132, and then fall out of the smooth roller through the circular holes 1311 on the side surface of the cylindrical section 132. The first pair of polishing rollers 13 consists of two polishing rollers positioned on the same horizontal plane. The frustum sections 131 of the two rollers have identical structures, and the bottom end of the larger frustum section 131 of each roller is flush with the bottom end of the smaller frustum section 131 of the other roller. There is no gap between the grinding surfaces of the two rollers. The first pair of polishing rollers 13 can crush materials to a particle size of less than diameter C, where C is 1 mm. The diameter of the circular holes 1311 on the side surface of the frustum section 131 is 1 mm, and the diameter of the circular holes 1322 on the side surface of the cylindrical section 132 is 2 mm.
[0060] The structure of the second smooth roller pair 14 is similar to that of the first smooth roller pair 13, except that the second smooth roller pair 14 can crush the material to a particle size of less than the diameter D, where the particle size D is 0.5mm. The diameter of the circular hole on the side surface of the frustum section of the second smooth roller pair 14 is 0.5mm, and the diameter of the circular hole on the side surface of the cylindrical section of the second smooth roller pair 14 is 1mm.
[0061] The first carbide pin roller pair 11 can crush materials to a diameter of less than A; wherein, A is 4mm.
[0062] The second carbide pin roller pair 12 can crush materials to a diameter of less than B; wherein, B is 2mm.
[0063] The first four rollers 15 can crush materials to a diameter of less than E; where E is 0.1 mm.
[0064] The second and fourth rollers 16 can crush materials to a diameter of less than F; where F is 0.074 mm.
[0065] The first carbide pin roller pair 11, the second carbide pin roller pair 12, the first smooth roller pair 13, the second smooth roller pair 14, the first four rollers 15, and the second four rollers 16 are all powered by a Y3553-4 motor in conjunction with a DCY500-50 reducer.
[0066] The base material of the first cemented carbide pin roller pair 11 and the second cemented carbide pin roller pair 12 is 42CrMo.
[0067] The first smoothing roller pair 13 and the second smoothing roller pair 14 are made of 42CrMo material.
[0068] The rich ore powder pelletizing crushing system provided in this embodiment can process rich ore powder with a particle size of 8 mm into rich ore pelletizing powder with a particle size of no more than 0.074 mm and a mass content of no less than 85% (based on the total mass of rich ore pelletizing powder as 100%).
[0069] Example 2
[0070] This embodiment provides an apparatus for preparing pellets from rich mineral powder, such as... Figure 3 As shown, the device includes:
[0071] The crushing system 1, the batching, pelletizing and screening system 2, and the roasting system 3 are connected in series.
[0072] Crushing system 1 adopts the crushing system for preparing pellets from rich ore powder provided in Example 1.
[0073] The batching, pelletizing, and screening system 2 includes a batching chamber 21, a mixing chamber 22, a mixed material silo 23, a briquetting machine 24, and a screening device 25 connected in sequence. The batching chamber 21 is equipped with a rich ore pelletizing powder silo 211, a bentonite solid phase binder silo 212, a starch solid phase binder silo 213, and a dust collection silo 214. The rich ore pelletizing powder silo 211 is equipped with a variable frequency speed-regulating disc feeder and an electronic belt scale. The silo 211 is also equipped with a pressure-type top-mounted bag filter dust collector and a weighing level gauge for level detection and control of the feeding system. The bentonite solid phase binder silo 212 is equipped with a direct-load belt scale and a pressure-type top-mounted bag filter dust collector. The silo 212 is also equipped with a weighing level gauge for level detection and control of the feeding system. The starch solid binder silo 213 is equipped with a direct-lift belt scale, and a pressure-type bag filter dust collector is installed on top of the silo. The silo is also equipped with a weighing level gauge to detect material level and control the feeding system. Similarly, the dust collector silo 214 is equipped with a direct-lift belt scale, a pressure-type bag filter dust collector, and a weighing level gauge to detect material level and control the feeding system. In this embodiment, there are three rich ore pelletizing powder silos 211, one bentonite solid binder silo 212, one starch solid binder silo 213, and two dust collector silos 214. The discharge port of the crushing system 1 is connected to the inlet of the rich ore pelletizing powder silo 211 via a belt conveyor. The discharge ports of each silo in the batching chamber 21 are connected to the inlet of the mixing chamber 22 via a belt conveyor. The mixing chamber 22 is equipped with a continuous high-power mixer capable of vertical mixing. The discharge port of the mixing chamber 22 is connected to the inlet of the mixing silo 23 via a belt conveyor and a plow-type unloader connected to the belt conveyor. The mixing silo 23 is equipped with a liquid phase binder feeding port. The mixing silo 23 is connected to the briquetting machine 24 via a belt conveyor equipped with a belt scale; the belt conveyor is equipped with a moisture detector to detect the moisture content of the material being transported by the belt conveyor, thereby controlling the amount of water added to the briquetting machine 24. The briquetting machine 24 is equipped with a water inlet. Each silo in the batching, pelletizing, and screening system 2 is made of steel, lined with wear-resistant and non-stick material, and the conical section is equipped with a vibrator to prevent material blockage. The pellets pressed by the briquetting machine 24 fall into the screening equipment 25 for screening. The screening equipment 25 uses a 16mm aperture screen.
[0074] The roasting system 3 includes a chain grate 31, a rotary kiln 32, and an annular cooler 33 connected in series. This system allows materials processed by the chain grate 31 to fall into the rotary kiln 32 for further processing, and then into the annular cooler 33 for further processing. The chain grate 31 is sequentially equipped with a material distribution system, a forced-air drying section, a forced-air drying section, a preheating section I, and a preheating section II. The material inlet of the chain grate 31 is connected to the material outlet of the batching and pelletizing screening system 2 via a material collection belt conveyor. This allows materials discharged from the batching and pelletizing screening system 2 to be transported to the chain grate 31 via the material collection belt conveyor. The material collection belt conveyor is equipped with a belt scale to detect the amount of material being transported, thus helping to control the material thickness within the chain grate. The rotary kiln 32 is equipped with a kiln head hood and a kiln tail hood, and is equipped with a structural cooling fan. The rotary kiln roasts the materials inside the kiln through thermal radiation, and the rotary kiln can achieve a roasting temperature of 1250-1280℃. The annular cooler 33 is sequentially configured with a first cooling section, a second cooling section, and a third cooling section. The exhaust port of the first cooling section of the annular cooler 33 is connected to the air inlet of the preheating section I of the chain grate machine 31, thereby enabling the reheated air from the first cooling section to be reused as a heat source for the preheating section II. The exhaust port of the second cooling section of the annular cooler 33 is connected to the air inlet of the preheating section II of the chain grate machine 31, thereby enabling the reheated air from the second cooling section to be reused as a supplementary heat source for the preheating section I. The exhaust port of the third cooling section of the annular cooler 33 is connected to the air inlet of the preheating section II of the chain grate machine 31, thereby enabling the reheated air from the third cooling section to be reused as a heat source for the blower drying section. The exhaust port of the preheating section II of the chain grate machine 31 is connected to the air inlet of the exhaust drying section of the chain grate machine 31, thereby enabling the reheated air from the preheating section II to be reused as a heat source for the exhaust drying section.
[0075] The rich ore powder preparation pellet device also includes an electrostatic precipitator 4. The material inlet of the electrostatic precipitator 4 is connected to the exhaust outlet of the chain grate 31 in the roasting system 3, and the dust outlet of the electrostatic precipitator 4 is connected to the dust ash silo 214.
[0076] Application Example 1
[0077] The apparatus for preparing pellets from rich ore powder provided in Example 2 is used to prepare pellets from rich ore powder. Specifically, it includes:
[0078] 1. The rich ore powder undergoes raw material crushing, including:
[0079] Rich ore powder enters crushing system 1 and undergoes four-stage double-roll crushing and two-stage four-roll crushing in sequence to prepare rich ore pellet powder; wherein, the processing capacity of crushing system 1 is 70t / h.
[0080] The iron-rich powder used in this application example includes a mixture of hematite powder and magnetite powder in a mass ratio of 1:1. The total iron content (TFe) of the iron-rich powder is 66%, and the particle size of the iron-rich powder is 0-8 mm (excluding 0). The mass content of particles with a particle size not exceeding 0.074 mm in the final prepared iron-rich ore pelletizing powder is not less than 85% (based on the total mass of the iron-rich ore pelletizing powder being 100%).
[0081] 2. A mixture of rich ore pelletizing powder, bentonite, and dust collector ash is prepared to obtain a homogeneous material, including:
[0082] The prepared rich ore pelletizing powder is transported to the top of the rich ore pelletizing powder silo 211 by a conveyor belt and unloaded into the rich ore pelletizing powder silo 211; bentonite is blown into the bentonite solid phase binder silo 212 by compressed air.
[0083] The rich ore pelletizing powder silo 211, bentonite solid phase binder silo 212, and dust removal ash silo 214 are fed into the mixing chamber 22 according to the set values (83:15.5:1.5), and transported to the mixing chamber 22 by a conveyor belt. The materials are mixed evenly in the mixing chamber 22 to obtain a mixed material. The processing capacity of the mixing chamber is 250t / h.
[0084] 3. Mix the homogenized material with the liquid binder (starch aqueous solution) to obtain a mixture, comprising:
[0085] The mixed material is transported to the mixing silo 23 by a conveyor belt and unloaded into the mixing silo 23 by a plow-type unloader. Then, a liquid binder is added into the mixing silo 23 to obtain the mixed material.
[0086] 4. The mixture is mixed with water to obtain pelletizing material, which is then used for pelletizing, including:
[0087] The mixture in the mixing silo 23 is conveyed to the briquetting machine 24 by a belt conveyor equipped with a belt scale. Water is added to the mixture in the briquetting machine 24 to obtain pelletizing material. The pelletizing material is pelletized by the briquetting machine 24 to obtain pellets. The moisture content of the pelletizing material is 10% based on the mass of the pelletizing material as 100%.
[0088] 5. The pellets are screened, including:
[0089] The pellets produced by the briquetting machine 24 are screened using a 16mm aperture screen. The material that falls off the screen is the screened material, and the material that remains on the screen is the screen residue.
[0090] The screen residue is recycled, specifically by being transported together with the mixture in the mixing silo 23 to the briquetting machine 24 for reuse.
[0091] 6. The pellets are then laid out, including:
[0092] The screened material is transported to the feeding system (8mm aperture) of the chain grate 31 by the collecting conveyor belt for feeding. The material left on the feeding system is the product after feeding, and the material falling off the feeding system is the feeding residue.
[0093] The fabric residue is recycled, specifically by being transported together with the mixture in the mixing silo 23 to the briquetting machine 24 for reuse.
[0094] 7. The pellets are dried and preheated using a chain grate machine, including:
[0095] The fabricated product passes through the blower drying section, the exhaust drying section, the preheating section I, and the preheating section II on the chain grate machine 31 for preheating.
[0096] Among them, the blower drying section uses the regenerated air at nearly 350°C obtained by the three-stage cooling of the ring cooler 33 as a heat source for the blower drying of the pellets;
[0097] The exhaust drying section uses reheated air at around 400°C obtained from the second stage of preheating by the chain grate machine as a heat source for exhaust drying of the pellets. During the exhaust drying process, air is drawn from above the material layer downwards to dehydrate and dry the pellets, so that the pellets can withstand the high temperature during the preheating process without bursting.
[0098] The first stage of preheating uses hot air at 700°C or higher to preheat the pellets through the material layer; the second stage of cooling in the annular cooler 33 uses 700°C regenerated air as a supplementary heat source for the first stage of preheating.
[0099] In the preheating stage II, the 1050℃ regenerated air obtained from the first cooling stage of the annular cooler 33 passes through the material layer to preheat the pellets in the second stage.
[0100] 8. The production waste gas discharged from the chain grate machine 31 enters the electrostatic precipitator 4 for dust removal, and the resulting dust is transported to the dust ash silo 214 by pneumatic conveying through pneumatic pipeline.
[0101] 9. The pellets are calcined and consolidated using rotary kiln 32, including:
[0102] The pellets that have been dried and preheated in the chain grate machine 31 fall into the rotary kiln 32. The pellets are subjected to heat radiation in the kiln, and are tumbled and roasted to solidify, thereby obtaining uniform strength. The temperature in the rotary kiln is 1250-1280℃, and the residence time of the pellets in the rotary kiln 32 is 30 minutes.
[0103] 10. The pellets are cooled using an annular cooler 33 to obtain pellet ore, including:
[0104] After being roasted and solidified in the rotary kiln 32, the pellets enter the annular cooler 33 and are successively cooled through the first cooling section, the second cooling section, and the third cooling section, so that the temperature of the pellets reaches below 150℃, thus obtaining pellet mineral products.
[0105] Among them, the cooling air volume is adjusted by the 33 dampers of the ring cooler to obtain a regenerated air temperature of nearly 1100°C from the first stage of cooling, a regenerated air temperature of nearly 700°C from the second stage of cooling, and a regenerated air temperature of nearly 350°C from the third stage of cooling.
[0106] The FeO content of the pellets obtained in this embodiment is less than 1%.
[0107] The above description is only a preferred embodiment of the present utility model and is not intended to limit the present utility model. Any modifications, equivalent substitutions, improvements, etc., made within the spirit and principles of the present utility model should be included within the protection scope of the present utility model.
Claims
1. A crushing system for preparing pellets from rich ore powder, characterized in that, The system comprises at least four double rollers and at least two four-rollers connected in series. The at least four pairs of rollers include at least two carbide pin roller pairs installed first and at least two smooth roller pairs installed later. The smooth rollers used in the roller pair are hollow and include a frustum section and a cylindrical section. The cylindrical section is connected to the larger bottom surface of the frustum section. The side surface of the frustum section serves as the grinding surface of the smooth roller. Circular holes with the same size as the crushed particle are opened on the side surface of the frustum section. Circular holes with a diameter larger than the diameter of the circular holes on the side surface of the frustum section are opened on the side surface of the cylindrical section. The circular holes on the side surfaces of the frustum section and the cylindrical section are all connected to the inner cavity of the smooth roller. The smooth roller can make the crushed material fall into the inner cavity of the frustum section of the smooth roller through the circular holes on the side surface of the frustum section, then roll into the inner cavity of the cylindrical section of the smooth roller, and then fall out of the smooth roller through the circular holes on the side surface of the cylindrical section of the smooth roller.
2. The system according to claim 1, characterized in that, The diameter of the circular hole on the side surface of the cylindrical section is more than twice the diameter of the circular hole on the side surface of the frustum section.
3. The system according to claim 1, characterized in that, The system includes four double rollers connected in series and two four-rollers connected in series; The four roller pairs include two carbide pin roller pairs installed first and two smooth roller pairs installed later. The first of the two carbide pin roller pairs can crush materials to a diameter of less than A size; where A size is 4-40mm. The carbide pinned roller pair, with the latter one in the two carbide pinned roller pairs, can crush materials to a diameter of less than B; where B is 2-4mm. The first of the two smooth roller pairs can crush materials to a diameter of C or less; where C is 1-2 mm. The rear-mounted smooth roller pair of two smooth rollers can crush materials to a diameter of D or less; where D is 0.5-1mm. Among them, the diameter of the circular holes on the frustum section side surface of the optical roller of the first optical roller pair is C-sized; the diameter of the circular holes on the frustum section side surface of the optical roller of the second optical roller pair is D-sized. Among them, the first of the two four-roll crushers can crush materials to a diameter of less than E; the E size is 0.1-0.5mm. Among them, the rear four rollers of the two four-rollers can crush materials to a diameter of less than F; the F particle size is 0.074-0.1mm.
4. The system according to claim 1 or 3, characterized in that, The two polishing rollers used in each polishing roller pair are set on the same horizontal plane. The two polishing rollers have the same frustum structure, and the bottom end of the larger frustum section of each polishing roller is flush with the bottom end of the smaller frustum section of the other polishing roller. There is no gap between the polishing surfaces of the two polishing rollers.
5. An apparatus for preparing pellets from rich mineral powder, characterized in that, The device includes: The rich ore powder preparation pelletizing crushing system, batching, pelletizing and screening system and roasting system of any one of claims 1-4 are connected in series.
6. The apparatus according to claim 5, characterized in that, The batching, pelletizing, and screening system includes a batching chamber, a mixing chamber, a mixed material silo, a briquetting machine, and screening equipment connected in sequence. The batching room is equipped with a rich ore pelletizing powder silo and a solid phase binder silo; the mixed material silo is equipped with a liquid phase binder feed port; the briquetting machine is equipped with a water inlet; the feed inlet of the rich ore pelletizing powder silo is connected to the discharge port of the crushing system; and the discharge ports of each silo in the batching room are connected to the feed inlet of the mixed material silo.
7. The apparatus according to claim 6, characterized in that, The batching room is also equipped with a dust removal ash silo; the rich ore powder preparation pelletizing device also includes an electrostatic precipitator, the material inlet of which is connected to the exhaust gas outlet of the roasting system, and the dust removal ash outlet of which is connected to the dust removal ash silo.
8. The apparatus according to claim 5, characterized in that, The roasting system includes a chain grate machine, a rotary kiln, and an annular cooler connected in series. It can realize that the material processed by the chain grate machine falls into the rotary kiln for processing, and the material falls into the annular cooler for processing. The chain grate machine is sequentially equipped with a material feeding system, a blower drying section, an exhaust drying section, a preheating section I, and a preheating section II.
9. The apparatus according to claim 8, characterized in that, The exhaust port of the preheating section II of the chain grate machine is connected to the air inlet of the exhaust drying section of the chain grate machine, thereby realizing the reuse of the reheated air from the preheating section II as the heat source for the exhaust drying section.
10. The apparatus according to claim 8, characterized in that, The annular cooler is configured with a first cooling section, a second cooling section, and a third cooling section in sequence. Among them, the exhaust port of the first cooling section of the ring cooler is connected to the air inlet of the preheating section I of the chain grate machine, so as to realize the return of the reheated air of the first cooling section as the heat source of the preheating section II. Among them, the exhaust port of the second cooling section of the ring cooler is connected to the air inlet of the preheating section II of the chain grate machine, so as to realize the reuse of the reheated air of the second cooling section as a supplementary heat source for the preheating section I. The exhaust port of the three cooling sections of the ring cooler is connected to the air inlet of the blower drying section of the chain grate machine, thereby enabling the reheated air from the three cooling sections to be reused as a heat source for the blower drying section.