CN209613127U - A roller vertical mill - Google Patents

Abstract

The utility model discloses a kind of roller type vertical mills, including grinding machine shell, mill and grinding roller are provided in grinding machine shell, spout ring is provided between the excircle and grinding machine shell of mill, air inlet is additionally provided on the grinding machine shell of spout ring lower part, gas, which enters, forms an annular airflow in air inlet to grinding machine shell, mill edge is provided with collet, even circumferential is provided with switch-plate on collet, blinds wind blade is evenly distributed in spout ring annular, the top of blinds wind blade is provided with the crash panel of annular spread, the discharge gate for discharge is also connected in the bottom of shell, the vortex board of annular spread is provided on the inner wall of grinding machine shell middle and upper part, and tangent air inlet is provided on the grinding machine shell at this, the tangent air inlet is by benefit wind annular passage air feed.The utility model can balance and adjust the air quantity of improving material at spout ring, improve the classification efficiency of spout ring material, energy saving, while can also improve grinding efficiency.

Description

A roller vertical mill

technical field

The invention relates to a material bed grinding equipment, in particular to a roller vertical mill.

Background technique

Roller vertical mill is a kind of material bed grinding equipment, which is widely used in building materials, electric power and metallurgy industries. It is used to grind medium and brittle materials to form fine powder materials.

The mechanical term name (scientific name) of roller vertical mill is: roller mill. Compared with the ball mill that is placed horizontally, because this kind of mill works in a standing mode, it is customary in the cement industry to call it: vertical mill, also known as : Mill. It was used in industrial production in the UK in 1790, and it was not until 1928 that German talents officially applied the vertical mill to the coal powder preparation of the cement industry; my country introduced the German vertical mill in 1978, and the vertical mill technology began in 1984 and equipment localization research, and made the first prototype and put it into industrial operation.

Vertical mill is a kind of grinding machine that uses the principle of material layer grinding to grind materials. It has been widely used in cement, coal, electric power and other industries. It is a full-air-swept mill, which pulverizes the material through the relative movement of the grinding roller and the grinding disc, and dries and lifts the finely ground material by hot air, and is classified in the mill by the grading device, and the coarse powder falls into the grinding disc. It is crushed again; the finished product is sent out of the mill by air flow and collected by a dust collector. Specific process: After being squeezed, the materials to be ground will sink from the grinding disc to the nozzle ring under the action of centrifugal force, where the high-speed swirling wind blows up and blows away, and heavy particles such as metals and heavy ores will settle under the nozzle ring. discharge. The fine powder is brought to the upper part of the vertical mill, sorted by the separator, and the finished product enters the dust collector along with the gas to be collected, while the coarse particles fall into the inner cone under the action of gravity and settle on the grinding table through the central feeding tube. Enter a new round of circulation by centrifugal force. Thus, after many cycles, the heat transfer between the particles and the gas causes the water to evaporate.

The energy utilization rate of the vertical mill is higher than that of the ball mill. It integrates fine crushing, drying, grinding, powder selection, and transportation, and has high grinding efficiency, low power consumption (20-30% power saving compared with ball mills), large drying capacity, convenient product fineness adjustment, and technological process. Simple, small footprint, low noise (20 decibels lower than ball mills), less metal consumption, easy maintenance, etc.

There are some problems in the production of the existing roller vertical mill:

1. In actual production, all materials need to be dispersed, blown back and brought fine powder into the sorting equipment by the airflow ejected from the nozzle ring. The efficiency of sorting is very important, it also determines the size of the required air volume, the crushed material on the grinding disc is partly in the form of agglomerates or aggregates, and generally slides down on the flat retaining ring to the nozzle ring. Entering the spout ring under the action of gravity, the falling materials are relatively concentrated and close to the inner side, and cannot be impacted and dispersed better during the process of falling through the air ring. High resistance, large resistance, at the same time, the fine powder in the agglomerated or agglomerated materials cannot achieve impact dispersion, and the contact space with the air flow is small, and cannot be separated in time, and it will be discharged from the slag port as the larger group of materials fall into the outside. It becomes the external discharge material, the sorting efficiency is low, and because the airflow sorting efficiency is low, a lot of airflow does not participate in the dispersion of materials and directly rises into the subsequent parts, which also wastes a lot of air volume energy. As relying on the lifting force of the wind ring airflow to realize the sorting and lifting of the materials that fall off the grinding table due to the centrifugal force, because the sorting efficiency of the airflow at the nozzle ring is low, in order to increase the amount of materials lifted by the airflow and ensure the sorting efficiency, it has to be added Increase the air volume and wind speed of the airflow here. The higher the wind speed, the better the sorting efficiency. The consequence is that the wind speed at the nozzle ring is difficult to reduce, the resistance increases, and the energy consumption increases. Usually the wind speed at the nozzle ring reaches above 50m/s, and some roller vertical mills even reach 70-80m/s. Such a high wind speed directly leads to the resistance at the nozzle ring reaching 2000-4000Pa. However, if the materials are simply sorted out and carried, such a high wind speed is not needed, so the wind speed of the nozzle ring needs to be greatly reduced. To reduce the wind speed of the nozzle ring, the problem of breaking up the grinding disc materials must be solved first. Secondly, it is necessary to solve the problem of material distribution at the nozzle ring, and secondly, to solve the problem of the gradient change of wind speed. Where there is more material, the wind speed should be faster, and where there is less material, the wind speed should be lower. The air volume should be distributed according to the distribution of materials.

2. In production, the fineness of R80um sieve is generally controlled. For the preparation of raw meal powder on the cement production line, it is generally controlled at 15-20%, and R200um is controlled at 1-2%. In the actual raw meal powder, In order to achieve this control index, most of the particles are smaller than 60um, and most of the particles blown through the nozzle ring are relatively large, a large part of which is definitely not what we need, and does not need to be brought in. The powder is selected in the upper powder classifier and needs to be ground again.

Generally, the pressure difference of the mill is relatively large, that is, the gas resistance is relatively large. The main reason is that the dust concentration in the updraft is relatively large. We do not need to enter too many coarse powder particles into the powder selection, and there is a large amount of internal circulation. The airflow resistance leading to upward movement is relatively large, and the pressure difference of vertical mills is generally high, generally between 6000-10000Pa. Such a large resistance requires a lot of energy consumption, which directly increases the rise in energy consumption and reduces the selection The powder selection efficiency of the powder machine. Therefore, the problem of too high internal concentration needs to be solved.

In addition, all the gas inside the vertical mill enters from the nozzle ring. The air volume for lifting materials at the lower part of the vertical mill is smaller than the air volume for powder selection. The air volume entering the lower nozzle ring can blow up the fine powder and bring it to the upper powder separator. Don't use too much air volume, if the air volume is greatly reduced, it will definitely save energy. Reducing the air volume at the nozzle ring will increase the circulation of the discharged material at the same time. This is also the process of external circulation grinding that everyone advocates and respects at present. It increases the amount of discharged material and reduces the amount of material transported by gas, thereby reducing Energy consumption inside the mill. Increasing the amount of discharged materials does not consume too much energy, but if the airflow is used to lift the materials, it will consume a lot of energy.

Contents of the invention

The object of the present invention is to provide a roller vertical mill in order to overcome the above problems.

In order to achieve the above object, the method adopted in the present invention is: a roller vertical mill, comprising a mill housing, a grinding disc and a grinding roller are arranged in the mill housing, and the outer circumference of the grinding disc and the mill housing A spout ring is arranged between them, and an air inlet is also set on the mill shell at the lower part of the spout ring, and the gas enters the air inlet to form an annular air duct in the mill shell, and a material retaining ring is set at the edge of the grinding disc , on the upper circle of the retaining ring, there is evenly set a material shifting plate, in the nozzle ring, there are evenly distributed louver wind guide vanes in the ring, and on the upper part of the louver air guide vanes, there are ring-shaped impact plates, and in the shell The bottom of the body is also connected with a discharge port for discharge, and a windshield ring is arranged on the upper part of the nozzle ring, and the windshield ring is used to adjust the upward airflow to move inward; The inner wall of the upper middle part of the machine housing is provided with circularly distributed vortex plates, and a tangential air inlet is provided on the mill housing there, and the tangential air inlet is supplied by the supplementary air annular air duct and distributes the air evenly. The air volume is given to each tangential air inlet; a powder selection shell is arranged on the upper part of the mill shell, and a powder selection separator is arranged in the powder selection shell.

As an improvement of the present invention, the nozzle ring below the grinding roller is partially blocked by a windshield.

As an improvement of the present invention, an air volume detector that can detect the air volume in real time is installed in the tangential air inlet, and an electric air regulating valve is installed on the tangential air inlet for real-time adjustment to ensure that each tangential The air inlet evenly enters the air.

As an improvement of the present invention, the grinding disc is installed on a vertical reducer, and the reducer is powered by a motor.

As an improvement of the present invention, the rotating cage inside the powder separator is connected to the reducer of the powder separator through the main shaft assembly, the reducer is driven by the main shaft drive motor, and the transmission device is installed on the upper air outlet housing.

As an improvement of the present invention, a scraper is installed around the grinding disc, and the scraper scrapes the material to the discharge port at the lower part, so that it is discharged out of the mill.

As an improvement of the present invention, the grinding rollers are arranged on the support and evenly distributed around the periphery of the mill shell.

As an improvement of the present invention, the nozzle ring includes an inner plate and an outer plate, and the impact plate is distributed in the middle of the nozzle ring.

As an improvement of the present invention, the central feeding pipe of the separator corresponds to the center of the grinding disc.

As an improvement of the present invention, the air inlet is arranged on the side of the mill housing.

Beneficial effect:

1. By adding bypass air intake in the middle of the mill shell, it can not only balance and adjust the air volume of the upward airflow in the mill to ensure the air volume of powder selection; at the same time, it can also accelerate the airflow brought up again, which is beneficial to bring The dust that comes up will not fall, and it is also beneficial to reduce the concentration of powder selection, improve the efficiency of powder selection, and reduce the pressure difference of the mill. In addition, the coarse particles brought up are pre-separated to prevent these coarse particles from rising again , reduce the dust concentration in the updraft and reduce the airflow resistance;

2. A series of material impact plates are set on the louver guide vanes of the nozzle ring, and the material is thrown outward at a certain speed by the material shifting plate on the material retaining ring on the grinding disc, and hits the material impact plate. The plates are arranged at a certain angle on the louver air guide blades to ensure that the materials are well distributed in the radial direction. After the materials are impacted and dispersed, they are distributed in the middle of the inner and outer plates of the nozzle ring, so that the materials and the air flow have as much contact area as possible. , play a good sorting role;

3. While the air flow is in good contact with the material, it can reduce the air volume and wind speed, and reduce the air flow resistance at the nozzle ring, so as to achieve the purpose of energy saving and consumption reduction;

4. Sealing part of the outlet of the nozzle ring at the lower part of the grinding roller can reduce the erosion of the grinding roller shaft by the dust carried by the airflow and improve the service life of the grinding roller.

Description of drawings

Fig. 1 is a structural representation of the present invention;

Fig. 2 is the A-A direction sectional view of the present invention;

Fig. 3 is a schematic diagram of the partial structure of the grinding disc and the nozzle ring of the present invention;

Fig. 4 is B-B direction sectional view of the present invention;

Fig. 5 is an enlarged view of part C of the present invention.

The components in the figure are: 1. Motor, 2. Vertical reducer, 3. Scraper plate, 4. Windshield ring, 5. Grinding plate, 6. Annular air duct for supplementary air, 7. Tangential air inlet, 8. Air volume tester, 9. Powder separator, 10. Annular air duct, 11. Reducer, 12. Transmission motor, 13. Powder selection shell, 14. Feed inlet, 15. Inner cone, 16. Vortex plate , 17, grinding roller, 18, spout ring, 19, bracket, 20, air inlet, 21, discharge port, 22, mill shell, 23, inner plate, 24, outer plate, 25, louver air guide vane, 26, impact plate, 27, material shifting plate, 28, material retaining ring, 29, windshield, 30, supplementary air inlet, 31, air outlet housing.

Detailed ways

The present invention will be further illustrated below in conjunction with the accompanying drawings and specific embodiments. This embodiment is implemented on the premise of the technical solution of the present invention. It should be understood that these embodiments are only used to illustrate the present invention and are not intended to limit the scope of the present invention.

Example 1:

A kind of roller vertical mill as shown in Figure 1 and Figure 2, comprises mill housing 22, is provided with grinding disc 5 and grinding roller 17 in described mill housing 22, and described grinding disc is installed in vertical On the reducer 2, the vertical reducer 2 is powered by the motor 1.

The grinding rollers 17 are arranged on the support 19 and evenly distributed around the periphery of the mill shell 22 . A nozzle ring 18 is arranged between the outer circumference of the grinding disc 5 and the mill housing 22, and an air inlet 20 is also arranged on the mill housing 22 at the bottom of the nozzle ring 18, and the gas enters the air inlet 20 to the mill housing 22 An annular airflow is formed inside and passes through the nozzle ring 18; the lower part of the nozzle ring 18, specifically at the bottom of the mill housing 22, is provided with a discharge port 21 for discharging the particles from the mill housing 22, and around the grinding disc 5 A scraper 3 is installed, and the scraper 3 scrapes the material to the outer discharge port 21 at the lower part, so that it is discharged out of the mill.

A retaining ring 28 is arranged at the edge of the grinding disc 5, and a material shifting plate 27 is uniformly arranged on the upper circumference of the retaining ring 28, and louver air guide vanes 25 are uniformly distributed annularly in the nozzle ring 18. Ring-shaped impact plates 26 are arranged on the upper part of the wind guide vanes 25, and a windshield ring 4 is also arranged on the upper part of the nozzle ring 18, and the windshield ring 4 is used to adjust the upward airflow to move inwardly.

On the nozzle ring 18 below the grinding roller 17, a windshield 29 is used to partially block the nozzle, which can reduce the erosion of the grinding roller shaft by the dust carried by the airflow and improve the service life of the grinding roller.

The inner wall of the upper part of the mill housing 22 is provided with annularly distributed vortex plates 16, and a tangential air inlet 7 is arranged on the mill housing 22 there, and the tangential air inlet 7 is supplemented by The wind circular air duct 6 supplies air, and evenly distributes the air volume to each tangential air inlet 7 .

A powder selection housing 13 is arranged on the upper part of the mill housing 22 , and a powder selection separator 9 is arranged in the powder selection housing 13 . The rotating cage inside the powder separator 9 is connected to the powder separator reducer 11 through the main shaft assembly, and the reducer 11 is driven by the main shaft transmission motor 12, and the transmission motor 12 is installed on the upper air outlet housing 31.

An air volume detector 8 capable of real-time detection of the air volume is installed in the tangential air inlet 7, and an electric air regulating valve is installed on the tangential air inlet 7 for real-time adjustment to ensure that each tangential air inlet 7 enters the wind uniform.

The working process of the pre-separation bypass wind roller type vertical mill of the present invention is as follows:

The material is fed in the feed port 14, and enters the central position of the grinding disc 5 in the feeding pipe at the bottom of the inner cone 15 through the chute. The grinding disc 5 is installed on the vertical reducer 2, and the motor 1 provides power to the reducer 2 to drive the grinding disc 5 to rotate. The materials on the grinding disc move outwards with the action of centrifugal force and move to the grinding roller 17. The rollers 17 are installed on the support 19, and are evenly distributed on the periphery of the mill shell 22 in several equal parts. The material on the grinding disc 5 is between the grinding roller 17 and the grinding disc 5, and is crushed by the grinding roller 17, and the material after rolling continues to move to the outer edge, and moves to the material retaining ring 28 on the outermost edge of the grinding disc 5.

The upper circumference of the retaining ring 28 is evenly provided with a pusher plate 27, and the material is driven by the pusher plate 27, and is thrown outwards, and hits the impact on the upper part of the louver air guide vane 25 arranged inside the nozzle ring 18 at a certain speed. On the plate 26, the agglomerated materials in the impacted materials are broken up and dispersed in the middle area between the outer plate 24 and the inner plate 23 of the spout ring 18, and are subjected to the effect of their own gravity and fall downwards. During the process, under the action of the upward airflow in the annular air duct, the dispersed coarse and fine materials are sorted, and the larger particles fall into the annular air duct, and are scraped to the row by the scraper 3 installed with the grinding disc 5. The material is discharged from the material port 21 to form an external discharge, and these materials are sent into the mill shell 22 again via the lifting device for further grinding.

Medium-sized particles are deflected by the air flow through the windshield ring 4 and flow inwardly and upwardly. Their own gravity is greater than the support force of the air flow, and then fall back onto the grinding disc 5 for grinding again, while the finer particles are crushed by the grinding wheel 5. The airflow at the nozzle ring 18 is carried directly upwards.

Below the grinding roller 17, the part of the spout ring 18 is partially blocked with the windshield 29, so as to eliminate the situation that the air flow here scours the axis of the grinding roller 17 upwards. On the retaining ring 28 on the edge of the grinding disc 5, several shifting plates 27 are arranged, and the material turned over from the retaining ring 28 is no longer allowed to slip, but is given a certain speed by the shifting plates 27, greatly The speed when the material is discharged from the retaining ring 28 is improved, laying the foundation for breaking up the agglomerate material. We set a series of material impact plates 26 on the louver guide vanes 25 of the spout ring 18, and the material is thrown outward at a certain speed by the material pushing plate 27 on the material retaining ring 28 on the grinding disc 5, and the material hits the impact plate. On the plate 26, the impact plate 26 is arranged at a certain angle on the louver guide vane 25 to ensure that the material is better distributed in the radial direction. , so that the material and the air flow have as much contact area as possible, and play a good role in separation.

The fine powder is brought to the upper part of the vertical mill by the airflow, and the upward airflow carries the finer dust upwards to the middle area. Under the action of the circular and tangential airflow, the gas flow rate is further strengthened, and some of the coarser particles are affected by the centrifugal force. , hit the vortex plate 16 and lose kinetic energy, then move downward, and finally fall into the scraping area of the nozzle ring 18 bottom. Part of the material has no kinetic energy to move upward in the area of the vortex plate 16 that is evenly distributed in the circumferential direction, and is separated in advance. These are also materials that we do not need to select powder. After falling, the dust concentration of the upward moving airflow will be reduced. Pressure loss, saving energy. The airflow after the concentration reduction continues upwards and enters the powder separator 9 for separation. The coarser materials are rejected by the rotating cage in the powder separator 9 and fall into the inner cone 15 and enter the center of the millstone 5 to continue powdering. Grinding, the finer materials are carried by the gas, and enter the follow-up dust collector through the air outlet 10 for gas-solid separation to collect the finished fine powder we need. Thus, after many cycles, the particles are ground, and in the process of grinding, some heat exchange is also carried out between the particles and the gas to dry the materials.

On the outer side of the middle and upper part of the mill cylinder, we installed evenly distributed tangential air inlets 7, which are supplied by the supplementary air annular air duct 6, and distribute the air volume to each tangential air inlet 7 as evenly as possible. . The supplementary air annular air duct 6 is fed by one or more supplementary air inlets 30 . In the middle of the tangential air inlet 7, an air volume detector 8 capable of real-time detection of the air volume is installed, which is detected in real time during the production process, automatically adjusted according to the detection data, and adjusted in real time through the electric air regulating valve to ensure that several evenly distributed The tangential air inlet 7 of the tangential air inlet evenly enters the air, and also adjusts the air volume coming in from the lower annular air duct air inlet 20 from the air volume data detected in addition, so as to realize the balance and adjustment of the upper and lower air volumes. For the powder separator, sufficient air volume for powder selection is required. For the original vertical mill, all the powder selection air volume enters from the lower part through the nozzle ring 18, which is used to blow away and lift the powdery materials, while the air volume used by the vertical mill is generally larger, and according to the raw material, the gas carries the material concentration. It is much higher than the raw material feeding concentration and powder selection concentration we need, so the air volume from the lower nozzle ring 18 can be reduced. In order to adjust and ensure the powder selection air volume, the bypass tangential air intake is used to adjust.

By increasing the powder selection bypass air intake in the middle and upper part of the mill shell 22, it has three functions: one is to balance and adjust the air volume of the upward airflow in the mill to ensure the powder selection air volume; Acceleration is conducive to the fine powder dust brought up will not fall, and it is also conducive to reducing the concentration of powder selection and improving the efficiency of powder selection. The third is to pre-separate the coarse particles brought up, and do not let these coarse particles rise again. , reduce the dust concentration in the updraft and reduce the airflow resistance.

While the air flow at the nozzle ring 18 is in good contact with the material, the air volume and wind speed can be reduced, and the airflow resistance at the nozzle ring 18 can be reduced, thereby achieving the purpose of saving energy and reducing consumption.

The technical means disclosed in the solution of the present invention are not limited to the technical means disclosed in the above technical means, but also include technical solutions composed of any combination of the above technical features. It should be pointed out that those skilled in the art can make some improvements and modifications without departing from the principle of the present invention, and these improvements and modifications are also considered as the protection scope of the present invention.

Claims (10)

1. a kind of roller type vertical mill, including grinding machine shell, are provided with mill and grinding roller in the grinding machine shell, feature exists In: between the excircle and grinding machine shell of mill it is provided with spout ring, is additionally provided on the grinding machine shell of spout ring lower part Air inlet, gas, which enters, forms an annular passage in air inlet to grinding machine shell, and the mill edge is provided with backgauge Circle, even circumferential is provided with switch-plate on collet, is evenly distributed with blinds wind blade in the spout ring annular, The top of blinds wind blade is provided with the crash panel of annular spread, is also connected in the grinding machine shell bottom for arranging The discharge gate of material is additionally provided with air baffle ring on the spout ring top, and the air baffle ring is used to adjust in upward air-flow It moves inwardly；The vortex board of annular spread, and the mill at this are provided on the inner wall of the grinding machine shell middle and upper part It is provided with tangent air inlet on casing body, which is uniformly distributed air quantity to each by benefit wind annular passage air feed Tangent air inlet；It is provided on the top of grinding machine shell and selects powder shell, select powder separator selecting to be provided in powder shell.

2. a kind of roller type vertical mill according to claim 1, it is characterised in that: the spout ring below grinding roller uses wind deflector Carry out partial sealing.

3. a kind of roller type vertical mill according to claim 1, it is characterised in that: be equipped with energy in the tangent air inlet The air quantity detector of real-time detection air force, and electronic adjusting valve is installed on tangent air inlet and is adjusted in real time, really It is uniform to protect each tangent air inlet air inlet.

4. a kind of roller type vertical mill according to claim 1, it is characterised in that: the mill is mounted on vertical type speed reducer (change gear) On, power is provided to speed reducer by motor.

5. a kind of roller type vertical mill according to claim 1, it is characterised in that: the rotating cage of powder separator interior is selected to pass through main shaft Assembly is connected with powder concentrator speed reducer, which is driven by spindle drive motor, the speed reducer and spindle drive motor peace On the outlet air shell on top.

6. a kind of roller type vertical mill according to claim 1, it is characterised in that: mill surrounding is equipped with material scraping plate, by scraper Thus material scraper to lower part outlet discharge port is discharged outside grinding machine plate.

7. a kind of roller type vertical mill according to claim 1, it is characterised in that: the grinding roller setting on the support, and waits Divide and is evenly distributed on grinding machine shell periphery.

8. a kind of roller type vertical mill according to claim 1, it is characterised in that: the spout ring includes interior plate and outer Side plate, the crash panel are distributed in position among spout ring.

9. a kind of roller type vertical mill according to claim 1, it is characterised in that: the center feeder pipe and mill of the separator The center of disk is corresponding.

10. a kind of roller type vertical mill according to claim 1, it is characterised in that: the mill is arranged in the air inlet The side of casing body.