Vertical crusher and method for diagnosing crushing rollers thereof

Abstract

To provide a structure capable of obtaining information on an abrasion amount of a roller tire without stopping operation of a vertical pulverizer, and a diagnostic method.SOLUTION: In a vertical pulverizer 11, a freely rotatable pulverization roller (roller tire 17) is arranged on a rotation table 18, and a raw material is pulverized by compression and shear force by catching the raw material between the rotation table and the pulverization roller (roller tire 17). In the vertical pulverizer 11, a cylindrical partition member 13 is provided extending from a dam ring of the rotation table 18 to an internal cone 16 along a lower casing 12B side surface. In a position after catching the pulverization roller (roller tire 17), a discharge port 24 corresponding to the pulverization roller (roller tire 17) is provided in the partition member 13, a blade 10 corresponding to the discharge port 24 is provided in the outer side surface of the partition member 13, and as a result a gas blow-up passage is formed.SELECTED DRAWING: Figure 1

Description

[Technical field]

[0001] This invention relates to a vertical pulverizer for pulverizing solid materials such as coal, limestone, cement raw materials, clinker, slag, oil coke, and other inorganic and organic raw materials. [Background technology]

[0002] A pulverizer is a device that pulverizes coal, limestone, cement raw materials, etc. into fine powder, and a vertical pulverizer presses a pulverizing roller against a disk-shaped table using hydraulic or centrifugal force, compressing and pulverizing the materials between the pulverizing roller and the rotating table. This vertical pulverizer is widely used because it consumes little power per unit of crushed amount and has the characteristics of efficient crushing.

[0003] When raw materials are fed into the vertical crusher through a chute, they pass through an internal cone, fall to the center of the rotating table, are pushed to the outer periphery by centrifugal force, and are crushed by compression and shear force when they are caught between the crushing roller and the rotating table.In this crusher, there is a gap between the outer periphery of the rotating table and the casing, and gas is ejected from the gap.

[0004] The crushed raw material is carried upward by the gas current toward the gap between the outer circumference of the rotating table and the casing. In this way, it is sent to the classifier (separator) attached above, where it is classified, and finally collected as a product. Also, if the size of the raw material is too large to be crushed sufficiently, it cannot pass through the classifier and is fed back onto the rotating table to be crushed again.

[0005] In this way, the gas current is used to transport the crushed material to the top of the machine and remove it, while crushed material with a particle size too large to be transported by the gas current falls from the rotating table and is collected from a discharge chute below the machine body. The collected crushed material is then fed back onto the rotating table from above the machine body by a bucket elevator and repeatedly crushed until the desired particle size is reached.

[0006] In order for a vertical crusher to perform its crushing function, it is important that the crushing parts (especially the roller tires) maintain their specified shape. However, as the crushing operation continues, wear progresses over time and the shape of the roller tires becomes distorted.

[0007] Depending on the location and type of raw material, grinding conditions, etc., the raw material fed into the vertical grinding mill flows unevenly onto the rotating table, resulting in an uneven layer thickness of the raw material layer. As a result, the load on the roller tires of the multiple grinding rollers fixed inside the casing varies depending on the installation location of the grinding rollers, and the degree of wear of each grinding roller also varies. When the roller tires wear out in this way, the raw material is not crushed sufficiently, and the quality and quantity of the crushed material obtained decreases. In addition, extra energy is consumed to re-pulverize the material that was not sufficiently pulverized by the classifier. Even if re-pulverization is performed, it is difficult to obtain pulverized material of the desired particle size with such worn roller tires. For this reason, as disclosed in Patent Document 1, a structure is adopted in which the roller tires of the crushing roller can be replaced when wear progresses. [Prior art documents] [Patent documents]

[0008] [Patent Document 1] JP 2007-061684 A Summary of the Invention [Problem to be solved by the invention]

[0009] However, until now, the wear of roller tires has been considered an important control value for safe operation, but the measurement could only be done when the vertical crusher was stopped, which was an inefficient task, and it was not possible to check the progress during the process, so it had to be estimated with little information. Therefore, there was a risk of unexpected operation stoppages and sudden maintenance work. In order to avoid these risks, roller tires were replaced before the expected lifespan, even though they still had plenty of life left, which was wasteful.

[0010] In view of the above problems, the problem to be solved by the present invention is to provide a vertical crusher and a diagnostic method that can obtain information on the amount of wear of roller tires without stopping the operation of the vertical crusher. [Means for solving the problem]

[0011] In order to solve the above problems, as a first means, a vertical crusher is provided in which a rotatable crushing roller is disposed on a rotating table, and raw materials are crushed by compression and shear force by being caught between the rotating table and the crushing roller, a cylindrical partition member is provided which extends from above the dam ring of the rotary table along the side surface of the lower casing to an inner cone; The partition member The crushing roller is rotated at a position after the crushing roller is engaged. A grid or fence pattern is arranged in the same number as the A discharge port and an outer surface of the partition member Extending from the lower end of the partition member toward the classifier Slats Same number as the above exhaust outlets By preparing , between the blades across the annular gap between the lower casing and the partition member Gas blow-up passage Same number as the roller tires formation The crushed material is blown upward through a gas blowing passage corresponding to each roller tire and conveyed along the vane to the classifier. The object of the present invention is to provide a vertical crusher. According to the first means, each crushing roller is provided with an outlet for discharging crushed material, and a gas blow-up passage can be formed by forming vanes on the outer surface of a cylindrical partition member along the gas flow from the outlet toward the top of the vertical crusher. This gas blow-up passage discharges crushed material that has become large enough to pass through the openings of each outlet corresponding to each crushing roller, and guides it to the classifier, preventing the consumption of unnecessary energy caused by the collision of the ascending air current and the natural falling current.

[0012] In order to solve the above problem, as a second means, the gas blowing up passage is formed in a spiral shape extending upward along the outer surface of the partition member, The object of the present invention is to provide a vertical crusher as described in the first means, in which the crushed material crushed by each crushing roller is guided to a classifier. According to the second means, a vane plate is provided for each outlet corresponding to each grinding roller to form a gas blow-up passage. This gas blow-up passage discharges crushed material that has become large enough to pass through the opening of each outlet corresponding to each grinding roller and guides it to the classifier, thereby preventing the consumption of unnecessary energy caused by the collision of the ascending air current and the gravity falling current. In addition, since a gas blow-up passage corresponds to each crushing roller, the progress of crushing by each crushing roller is reflected in the atmosphere in the gas blow-up passage.

[0013] In order to solve the above problems, as a third means, a gas blow-up passage corresponding to each of the crushing rollers is provided. To measure dust concentration, which indicates the concentration of ground material The object of the present invention is to provide a vertical crusher according to the first or second aspect, which is equipped with a dust concentration measuring mechanism. According to the third means, the dust concentration indicating the concentration of the crushed material in each gas blowing passage is continuously measured by a dust concentration measuring mechanism provided in each gas blowing passage corresponding to the crushing roller, thereby making it possible to estimate the progress of crushing in each crushing roller.

[0014] In order to solve the above problems, as a fourth means, A diagnostic method for a crushing roller used in the vertical crusher according to the first aspect, comprising: Installed in each gas blow-up passage To measure dust concentration, which indicates the concentration of ground materiala step of continuously measuring the concentration of finely pulverized material pulverized by the pulverizing rollers in each of the gas blow-up passages by a dust concentration measuring mechanism; Another object of the present invention is to provide a diagnostic method for a crushing roller, comprising a step of comparing the measured concentration with a predetermined reference value to estimate the condition of the crushing roller. According to the fourth means described above, the dust concentration indicating the concentration of the crushed material in each gas blow-up passage is continuously measured by a dust concentration measuring mechanism provided in the gas blow-up passage corresponding to each crushing roller, so that the progress of crushing in each crushing roller can be confirmed in real time and the condition of each crushing roller can be estimated, making it possible to replace worn roller tires of the crushing rollers at the appropriate time. Effect of the Invention

[0015] According to the present invention, by providing a gas blow-up passage corresponding to the roller tires of each crushing roller and a dust concentration measuring mechanism within the gas blow-up passage, not only can the waste of energy caused by the collision of the ascending air current and the gravity falling current be prevented, but also worn roller tires of the crushing rollers can be replaced at the appropriate time. [Brief description of the drawings]

[0016] [Figure 1] FIG. 2 is a side cross-sectional view of the vertical crusher of the present invention. [Diagram 2] 2 is a cross-sectional view taken along line AA in FIG. 1. [Diagram 3] FIG. 2 is a perspective view illustrating the arrangement of vane plates in the vertical crusher of the present invention. [Figure 4] FIG. 1 is a side cross-sectional view of a conventional vertical crusher. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0017] Hereinafter, an embodiment of the present invention will be described with reference to the drawings. After describing the prior art with reference to FIG. 4, the present invention will be described with reference to FIGS.

[0018] [Conventional vertical crusher 1] FIG. 4 is a side cross-sectional view of a conventional vertical crusher 1. As shown in the figure, the conventional vertical crusher 1 is equipped with a reducer installed below an upper casing 2A and a lower casing 2B forming an outer shell, a rotary table 8 driven by a drive motor (not shown), and a crushing roller. In addition, a funnel-shaped inner cone 6 is arranged above the rotary table 8, and a classifier 5 is fixed to the upper part of the inner cone 6. A cylindrical raw material supply port 3 is arranged coaxially with the center of the classifier 5 and the center of the lower opening of the inner cone 6, and raw material input from the raw material supply port 3 is piled up on the rotary table 8. The piled up raw material is caught between the roller tire 7 of the crushing roller and the rotary table 8 and crushed by compression and shear force. Furthermore, the crushed material is transported upward by the gas flow introduced from the gas inlet 9 located below the rotary table 8, and only the material of the desired particle size is taken out together with the gas from the upper outlet 4 at the top of the vertical crusher via the classifier 5.

[0019] [Vertical crusher 11 of the present invention] 1 is a side cross-sectional view of a vertical crusher 11 of the present invention. The vertical crusher 11 of the present invention is originally equipped with a plurality of crushing rollers, but the illustration shows only the roller tires 17, the discharge port 24, and the vanes 10 of one set of crushing rollers. In an embodiment of the present invention, a cylindrical partition member 13 is provided that extends from above the dam ring of the rotating table 18 along the side of the lower casing 12B to the classifier 15, surrounding the circumference of the rotating table 18 and surrounding the space between the rotating table 18 and the internal cone 16. A small gap is provided between the upper end of the cylindrical partition member 13 and the inner cone 16, and the lower end of the cylindrical partition member 13 and the rotating table 18 so that they do not come into contact with each other, and the partition member 13 is fixed to the side surface of the lower casing 12B by a support member (not shown). The cylindrical partition member 13 is made of a steel material having the same strength as the casing, and its outer diameter is the same as that of the rotating table.

[0020] The cylindrical partition member 13 is provided with a discharge port 24, which is located at a position after the roller tires 17 of the crushing roller are bitten (anti-biting position), and the crushed material that has been crushed to a predetermined particle size is discharged from the discharge port 24 and blown upward along the blades 10 to the classifier 15. Thereafter, the crushed material (product) is taken out from the upper outlet 14 through the classifier 15. The blade plate 10 is formed to extend in a spiral shape from the opposite bite side on the rotating table 18 to the classifier 15 above, while rotating along the outer surface of the partition member 13, at the same angle as the inclination angle of the airflow direction control plate 25. As shown in FIG. 1, the airflow direction control plates 25 are rectangular plates arranged tilted upward from the left side to the right side, and a plurality of them are provided at regular intervals along the annular gap.

[0021] Fig. 2 is a cross-sectional view taken along line AA in Fig. 1 when there are four crushing rollers. As shown in Fig. 2, the partition member 33 is provided with the same number of discharge ports 34 as the roller tires 37 so as to correspond to the roller tires 37 of the crushing rollers. In the annular gap between the lower casing 32B and the partition member 33, the partition member 33 is provided with the same number of vanes 30 as the discharge ports 34 so as to correspond to the discharge ports 34 along the outer surface of the partition member 33. In other words, since there are the same number of roller tires 37, discharge ports 34, and vanes 30, the same number of gas blow-up passages 36, which are passages between the vanes 30, are also formed in the annular gap between the lower casing 32B and the partition member 33, and the crushed material crushed by each roller tire 37 of the crushing roller is blown upward and transported through the corresponding gas blow-up passages 36.

[0022] 3 is a perspective view illustrating the arrangement of the vanes in the vertical crusher of the present invention. The vanes 40 are located in the annular gap between the lower casing 42B and the partition member 43, and are formed in a spiral shape starting from the lower right end of the fence-like or lattice-like discharge port 44 and revolving upward along the outer surface of the partition member 43 at the same angle as the inclination angle of the air direction control plate 45.

[0023] The opening of the discharge port 44 is shaped like a fence or a lattice so that only fine powder can pass through, and raw materials with large particle sizes that cannot pass through the slits or mesh are not discharged but remain on the rotating table and can be crushed again. In other words, by adjusting the opening size of the discharge port 44, it is possible to adjust the particle size to a certain degree to the desired particle size. In addition, crushed materials that could not pass through the classifier are supplied again to the rotating table via the internal cone. In this way, the frequency of natural falling flows occurring when pulverized material falls without being able to pass through the classifier can be reduced, thereby preventing the waste of energy caused by the collision of the rising air current toward the classifier, which occurs in conventional vertical pulverizers, with the natural falling flow caused by pulverized material falling without being able to pass through the classifier.

[0024] Furthermore, as shown in Fig. 2, since a gas blow-up passage 36 corresponds to each roller tire 37 of the crushing roller, the atmosphere in the gas blow-up passage 36 can reflect the progress of crushing by the roller tires 37. Therefore, a dust concentration meter (not shown) is provided in the gas blow-up passage 36 as a dust concentration measuring mechanism, and the progress of crushing by each roller tire 37 can be estimated by measuring the dust concentration indicating the concentration of the crushed material in the gas blow-up passage 36. This dust concentration meter is preferably of the light scattering type or light transmission type, and it is determined whether the value measured by the dust concentration meter in the gas blow-up passage 36 is higher or lower than a predetermined reference value. In other words, the dust concentration is higher when the crushing is performed normally. At this time, since the dust concentration in the gas blowing up passage 36 varies depending on the amount of raw material supplied, the predetermined reference value is determined taking the amount of raw material supplied into consideration. Further, the dust concentration measuring mechanism may be of a type that does not require gas sampling as described above, but may also be of a type that measures the dust concentration in gas sampled from inside the gas blow-up passage 36 by a collector.

[0025] As an example, in a vertical pulverizer equipped with gas blow-up passages a to d corresponding to roller tires a to d of a pulverizing roller, the values ​​measured by a dust concentration meter in the gas blow-up passage were judged to be higher or lower than a predetermined reference value. The results are summarized in Table 1.

[0026] [Table 1]

[0027] When the dust concentration measurement result is A, the concentrations in each gas blowing passage are all higher than the predetermined reference value, so the operating condition is determined to be stable, and the corresponding roller tires a to d can be diagnosed as being in a normal condition with no wear. Furthermore, if the dust concentration measurement result is B, the operating condition is determined to be unstable because the concentration in each gas blowing passage varies (some high and some low) from the predetermined standard value, and roller tires b and c, which showed dust concentration values ​​lower than the standard value, can be diagnosed as being suffering from advanced wear. If the dust concentration measurement result is C, the concentrations in each gas blowing passage are all lower than the predetermined reference value, so the operating condition is determined to be unstable and the corresponding roller tires a to d can be determined to be suffering from wear.

[0028] As described above, the degree of wear of the roller tires of each crushing roller can be diagnosed from the information obtained by measuring the dust concentration in the gas blow-up passage while the vertical crusher is in operation. Until now, in order to ensure stable operation, roller tires have been replaced before the expected lifespan even though there is still a sufficient life left, but this embodiment makes it possible to determine which roller tires should be replaced based on the degree of wear, and to perform the replacement work at an appropriate time without waste. Furthermore, in order to prevent unexpected maintenance work from occurring, maintenance work can be planned without stopping the operation of the vertical crusher.

[0029] In addition to the above, the configurations given in the above embodiments can be selected or appropriately changed to other configurations without departing from the spirit of the present invention. [Explanation of symbols]

[0030] 1. Conventional vertical crusher 2A, 12A Upper casing 2B, 12B, 32B, 42B Lower casing 3 Raw material input port 4, 14 Top outlet 5, 15 Classifier 6, 16 Inner Cone 7, 17, 37 Roller tires 8, 18 Rotating table 9, 19 Gas inlet 10, 30, 40 slats 11 Vertical crusher of the present invention 13, 33, 43 Partition members 24, 34, 44 outlet 25, 45 Wind direction control plate 36 Gas blow-up passage

Claims

1. A vertical crusher has a rotating table and a rotatable crushing roller disposed on the rotating table, and crushes raw materials by being caught between the rotating table and the crushing roller through compression and shear force, a cylindrical partition member is provided which extends from above the dam ring of the rotary table along the side surface of the lower casing to an inner cone; A vertical crusher comprising: a lattice-shaped or fence-shaped discharge outlet arranged at a position of the partition member after the crushing rollers are engaged with the partition member, the same number of discharge outlets as the crushing rollers; and vanes extending from the lower end of the partition member toward a classifier on the outer surface of the partition member, the same number of discharge outlets as the crushing rollers, thereby forming gas blow-up passages between the vanes in the same number as the roller tires across the annular gap between the lower casing and the partition member, and the crushed material is blown upward along the vanes through the gas blow-up passages corresponding to each roller tire and transported to the classifier.

2. The gas blow-up passage is formed in a spiral shape extending upward along the outer surface of the partition member, 2. The vertical crusher according to claim 1, wherein the crushed material crushed by each crushing roller is guided to a classifier.

3. 3. The vertical crusher according to claim 1, further comprising a dust concentration measuring mechanism for measuring a dust concentration indicating a concentration of the crushed material in each of the gas blow-up passages corresponding to each of the crushing rollers.

4. A method for diagnosing a grinding roller used in the vertical grinding machine according to claim 1, comprising: a step of continuously measuring the concentration of finely pulverized material pulverized by the pulverizing roller in each gas blow-up passage by a dust concentration measuring mechanism for measuring a dust concentration indicating the concentration of the pulverized material provided in each gas blow-up passage; The method for diagnosing a crushing roller includes a step of comparing the measured concentration with a predetermined reference value to estimate the condition of the crushing roller.

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