Abnormality detection system, solid fuel pulverizer, and abnormality detection method

Abstract

To provide an abnormality detection system, a solid fuel granulation device, and an abnormality detection method that can make a sensor detecting abnormality of a roller journal bearing hardly get out of order.SOLUTION: An abnormality detection system is an abnormality detection system for a roller journal bearing 59 which is accommodated in a housing 11 as an outer shell of a solid fuel granulation device and also supports a granulation roller 13 granulating solid fuel with a granulation table. The abnormality detection system comprises: a detection part 80 which is provided at a tip part, located outside the housing 11, of a journal head 45 supporting the granulation roller 13 through the roller journal bearing 59 and fitted to the housing 11, and detects information generated on the journal head 45 as the granulation roller 13 rotates; and a detection part which detects abnormality of the roller journal bearing 59 based upon the information that the detection part 80 detects.SELECTED DRAWING: Figure 2

Description

[Technical Field]

[0001] The present disclosure relates to an abnormality detection system, a solid fuel pulverizer, and an abnormality detection method. [Background technology]

[0002] Conventionally, solid fuels such as biomass fuels and coal are pulverized into fine powder within a predetermined particle size range in a pulverizer (mill) and then supplied to a combustion device. In the mill, the solid fuel fed onto a pulverizing table is pinched between the pulverizing table and a pulverizing roller to pulverize it. The pulverized solid fuel is then sorted using a classifier to select fine particles within a predetermined particle size range. The fine particles are then transported to a boiler by a carrier gas (primary air) supplied from the periphery of the pulverizing table, where they are combusted in the combustion device. In a thermal power plant, steam is generated by heat exchange with the combustion gas produced by burning the pulverized fuel in the boiler. This steam drives a steam turbine, which in turn drives a generator connected to the steam turbine, thereby generating electricity.

[0003] The crushing rollers are rotatably mounted on journal heads via roller journal bearings. The journal heads are swingably mounted on the mill housing. During crushing, a crushing load is applied to the crushing rollers via the journal heads by hydraulic cylinders or other devices mounted on the mill housing. Therefore, during mill operation, the roller journal bearings rotate while transmitting the load from the hydraulic cylinders or other devices to the crushing rollers. Roller journal bearings experience peeling and flaking on their rolling surfaces depending on the load and rotational speed. This shortens their lifespan with use, eventually leading to damage and the end of their service life. For this reason, it is known to detect abnormalities on the rolling surfaces in order to check the lifespan of roller journal bearings (see, for example, Patent Document 1).

[0004] Abnormalities on the rolling surface often appear as vibrations in the roller journal bearings. For this reason, the device described in Patent Document 1 is equipped with an abnormality detection sensor (vibration sensor) inside the crushing roller to detect vibrations emitted by the roller journal bearings and diagnose abnormalities in the roller journal bearings. [Prior art documents] [Patent documents]

[0005] [Patent Document 1] Japanese Patent Application Publication No. 2018-81012 Summary of the Invention [Problem to be solved by the invention]

[0006] However, the device described in Patent Document 1 has a vibration sensor installed inside the grinding roller. When the sensor for detecting abnormalities in the roller journal bearing is installed in close proximity to the grinding roller, which is the source of vibration, the sensor is prone to malfunction due to vibrations transmitted from the grinding roller. Furthermore, because the sensor is installed inside the high-temperature mill, the sensor is prone to malfunction. This reduces the reliability of the sensor. Furthermore, because the sensor is installed inside the grinding roller inside the mill, installing or replacing the sensor requires stopping the mill's operation and disassembling the grinding roller. This poses the problem that when replacing a sensor due to a malfunction or maintenance, or when adding a sensor to an existing mill, the sensor replacement or installation work takes a long time. During the replacement or installation work, the mill cannot be operated, which reduces the operating rate.

[0007] The present disclosure has been made in consideration of the above circumstances, and aims to provide an abnormality detection system, a solid fuel pulverization device, and an abnormality detection method that can reduce the likelihood of failure of sensors that detect abnormalities in roller journal bearings. Another object of the present invention is to provide an abnormality detection system, a solid fuel pulverizer, and an abnormality detection method that allow for easy replacement and addition of sensors. [Means for solving the problem]

[0008] In order to solve the above problems, the abnormality detection system, solid fuel pulverization device, and abnormality detection method of the present disclosure employ the following means. An abnormality detection system according to one aspect of the present disclosure is an abnormality detection system for a roller journal bearing that is housed inside a housing that forms the outer shell of a solid fuel pulverizer and rotatably supports a grinding roller that grinds solid fuel between it and a grinding table, and includes: a detection unit that supports the grinding roller via the roller journal bearing and is provided on an installation unit located outside the housing of a support unit attached to the housing, and that detects information generated on the support unit by the rotation of the grinding roller; and a detection unit that detects an abnormality in the roller journal bearing based on the information detected by the detection unit.

[0009] According to one aspect of the present disclosure, there is provided a method for detecting an abnormality in a roller journal bearing that is accommodated inside a housing forming an outer shell and rotatably supports a grinding roller that grinds solid fuel between the roller journal bearing and a grinding table, the roller journal bearing supporting the grinding roller and a support portion attached to the housing, the roller journal bearing being provided on an installation portion located outside the housing. R The method includes a detection step in which a detection unit detects information generated on the support unit by rotation of the crushing roller, and a detection step in which an abnormality in the roller journal bearing is detected based on the information detected by the detection unit. [Effects of the Invention]

[0010] According to the present disclosure, failure of the sensor that detects abnormalities in the roller journal bearing can be made less likely to occur. Furthermore, the sensor can be easily replaced or added. [Brief explanation of the drawings]

[0011] [Figure 1] 1 is a configuration diagram showing a solid fuel pulverizer and a boiler according to a first embodiment of the present disclosure. [Figure 2] FIG. 2 is a partially enlarged vertical cross-sectional view showing the vicinity of the crushing roller according to the first embodiment of the present disclosure. [Figure 3] FIG. 2 is a partially enlarged front view showing the periphery of a journal head according to the first embodiment of the present disclosure. [Figure 4] FIG. 2 is a partially enlarged perspective view showing the periphery of a journal head according to the first embodiment of the present disclosure. [Figure 5] FIG. 2 is a functional block diagram showing functions of a mill and a control unit according to the first embodiment of the present disclosure. [Figure 6] 4 is a graph showing band filter processing performed by a control unit according to the first embodiment of the present disclosure. [Figure 7] 4 is a graph showing envelope processing performed by a control unit according to the first embodiment of the present disclosure. [Figure 8] 4 is a graph showing an FFT process performed by a control unit according to the first embodiment of the present disclosure. [Figure 9] 6 is a graph showing a process performed by a control unit according to the first embodiment of the present disclosure to superimpose harmonic components on a bearing vibration frequency. [Figure 10] FIG. 10 is a hardware configuration diagram of a control unit according to a second embodiment of the present disclosure. [Figure 11] FIG. 10 is a functional block diagram showing functions of a control unit according to a second embodiment of the present disclosure. [Figure 12] FIG. 10 is a partially enlarged vertical cross-sectional view showing a load state of a crushing roller according to a second embodiment of the present disclosure. [Figure 13] FIG. 10 is a partially enlarged vertical cross-sectional view showing a roller inclination angle according to a second embodiment of the present disclosure. [Figure 14] FIG. 10 is a partially enlarged vertical cross-sectional view showing a roller inclination angle according to a second embodiment of the present disclosure. [Figure 15] FIG. 10 is a diagram illustrating a configuration example of a gap sensor according to a second embodiment of the present disclosure. [Figure 16]FIG. 10 is a diagram showing a flowchart of a remaining life estimation process according to a second embodiment of the present disclosure. [Figure 17] FIG. 10 is a diagram showing the estimation result of the remaining lifespan according to the second embodiment of the present disclosure. [Figure 18] FIG. 10 is a functional block diagram showing functions of a control unit according to a modified example of the second embodiment of the present disclosure. [Figure 19] FIG. 10 is a diagram showing a result of prediction of remaining life according to a modified example of the second embodiment of the present disclosure. [Figure 20] FIG. 10 is a functional block diagram showing functions of a control unit according to a modified example of the second embodiment of the present disclosure. [Figure 21] FIG. 10 is a diagram illustrating an example of a system related to a maintenance plan according to a modified example of the second embodiment of the present disclosure. [Figure 22] 10 is a graph showing the change in estimated remaining life and bearing abnormality degree per hour of a roller journal bearing according to a second embodiment of the present disclosure. DETAILED DESCRIPTION OF THE INVENTION

[0012] DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment of an abnormality detection system, a solid fuel pulverizer, and an abnormality detection method according to the present disclosure will be described below with reference to the drawings.

[0013] [First embodiment] DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS A first embodiment of the present disclosure will now be described with reference to the accompanying drawings. A power plant 1 according to this embodiment includes a solid fuel pulverizer 100 and a boiler 200. In the following explanation, "upper" refers to the vertically upward direction, and "upper" in terms such as upper part and upper surface refers to the vertically upward part. Similarly, "lower" refers to the vertically downward part, and the vertical direction is not precise and may include errors.

[0014] The solid fuel pulverizer 100 of this embodiment is an apparatus that pulverizes solid fuel, such as biomass fuel or coal, to generate pulverized fuel and supply it to a burner (combustion device) 220 of a boiler 200, for example. The power plant 1 including the solid fuel pulverizer 100 and the boiler 200 shown in FIG. 1 is equipped with one solid fuel pulverizer 100, but it may also be a system equipped with multiple solid fuel pulverizers 100 corresponding to each of the multiple burners 220 of one boiler 200.

[0015] The solid fuel pulverizing device 100 of this embodiment comprises a mill (pulverizing section) 10, a bunker (storage section) 21, a coal feeder (fuel supplying machine) 25, a blower (carrier gas supplying section) 30, a status detection section 40, and a control section 50.

[0016] The mill 10, which pulverizes solid fuel such as coal or biomass fuel to be supplied to the boiler 200 into finely divided fuel, which is a finely divided solid fuel, may be of a type that pulverizes only coal, or may be of a type that pulverizes only biomass fuel, or may be of a type that pulverizes biomass fuel together with coal. Here, biomass fuel refers to organic resources derived from renewable living organisms, such as thinned wood, waste wood, driftwood, grass, waste, sludge, tires, and recycled fuels (pellets and chips) made from these materials, but is not limited to the ones listed here.Biomass fuels are carbon neutral, meaning they do not emit carbon dioxide, a greenhouse gas, because they absorb carbon dioxide during the biomass growth process, and various uses for them are being considered.

[0017] The mill 10 comprises a housing 11, a grinding table 12, grinding rollers 13, a reducer (drive transmission unit) 14, a mill motor (drive unit) 15 connected to the reducer 14 and driving the grinding table 12 to rotate, a rotary classifier (classification unit) 16, a coal supply pipe (fuel supply unit) 17, and a classifier motor 18 that drives the rotary classifier 16 to rotate. The housing 11 is formed in a cylindrical shape extending in the vertical direction, and is a case that accommodates the crushing table 12, the crushing rollers 13, the rotary classifier 16, and the coal feed pipe 17. A coal feed pipe 17 is attached to the center of the ceiling portion 42 of the housing 11. This coal feed pipe 17 supplies solid fuel guided from the bunker 21 via the coal feeder 25 into the housing 11. It is arranged vertically at the center of the housing 11 and has its lower end extending into the interior of the housing 11.

[0018] A reducer 14 is installed near the bottom surface 41 of the housing 11, and a mill motor 15 connected to the reducer 14 transmits a driving force to rotate the grinding table 12, which is rotatably arranged. The grinding table 12 is a circular member in a plan view, and is arranged so that the lower end of the coal feed pipe 17 faces it. The upper surface of the grinding table 12 may, for example, have an inclined shape that is low in the center and rises toward the outside, with the outer periphery bending upward. The coal feed pipe 17 supplies solid fuel (in this embodiment, for example, coal or biomass fuel) from above toward the grinding table 12 below, and the grinding table 12 sandwiches the supplied solid fuel between itself and the grinding rollers 13 and grinds it.

[0019] When solid fuel is fed from the coal feed pipe 17 toward the center of the pulverizing table 12, the centrifugal force generated by the rotation of the pulverizing table 12 guides the solid fuel toward the outer periphery of the pulverizing table 12, where it is pinched and pulverized between the pulverizing table 12 and the pulverizing rollers 13. The pulverized solid fuel is blown upward by the carrier gas (hereinafter referred to as primary air) guided from the carrier gas flow path (hereinafter referred to as primary air flow path) 110, and is guided to the rotary classifier 16. An outlet (not shown) is provided on the outer periphery of the grinding table 12, through which primary air flowing in from the primary air flow path 110 flows out into the space above the grinding table 12 within the housing 11. A swirl blade (not shown) is provided at the outlet, which imparts a swirling force to the primary air blown out from the outlet. The primary air given a swirling force by the swirl blade becomes an airflow having a swirling velocity component, and transports the solid fuel pulverized on the grinding table 12 to the rotary classifier 16 located above in the housing 11. Of the pulverized solid fuel, particles larger than a predetermined particle size are classified by the rotary classifier 16, or fall without reaching the rotary classifier 16 and are returned to the grinding table 12, where they are pulverized again between the grinding table 12 and the grinding rollers 13.

[0020] The crushing roller 13 is a rotating body that crushes the solid fuel supplied onto the crushing table 12 from the coal supply pipe 17. The crushing roller 13 is pressed against the upper surface of the crushing table 12 and cooperates with the crushing table 12 to crush the solid fuel. 1 shows only one representative crushing roller 13, but multiple crushing rollers 13 are arranged at regular intervals in the circumferential direction so as to press against the upper surface of the crushing table 12. For example, three crushing rollers 13 are arranged at equal intervals in the circumferential direction on the outer periphery, at angular intervals of 120°. In this case, the portions of the three crushing rollers 13 that come into contact with the upper surface of the crushing table 12 (pressing portions) are equidistant from the rotational axis of the crushing table 12.

[0021] The crushing roller 13 can be swung and displaced up and down by the journal head 45, and is supported so as to be able to move towards and away from the upper surface of the crushing table 12. When the crushing table 12 rotates, the crushing roller 13 receives a rotational force from the crushing table 12 and rotates with it, with the outer circumferential surface of the crushing roller 13 in contact with the solid fuel on the upper surface of the crushing table 12. When solid fuel is supplied from the coal supply pipe 17, the solid fuel is pressed between the crushing roller 13 and the crushing table 12 and crushed. This pressing force is called the crushing load.

[0022] The support arm 47 of the journal head 45 is supported on the side of the housing 11 by an eccentric shaft 48 whose middle section is horizontally aligned, allowing the crushing roller 13 to swing and displace up and down about the eccentric shaft 48. A pressing device (crushing load applying unit) 46 is provided at the upper end section vertically above the support arm 47. The pressing device 46 is fixed to the housing 11 and applies a crushing load to the crushing roller 13 via the support arm 47 and the like so as to press the crushing roller 13 against the crushing table 12. The crushing load is applied, for example, by a hydraulic cylinder (not shown) operated by the pressure of hydraulic oil supplied from a hydraulic device (not shown) installed outside the mill 10. The crushing load may also be applied by the repulsive force of a spring (not shown). The detailed structure of the crushing roller 13 will be described later.

[0023] The reducer 14 is connected to a mill motor 15, and transmits the driving force of the mill motor 15 to the grinding table 12, causing the grinding table 12 to rotate around its central axis.

[0024] The rotary classifier 16 is provided at the top of the housing 11 and has a hollow, inverted cone-like outer shape. The rotary classifier 16 is provided with a plurality of blades 16a extending in the vertical direction around its outer periphery. The blades 16a are provided at predetermined intervals (equally spaced) around the central axis of the rotary classifier 16. The rotary classifier 16 is a device that classifies solid fuel pulverized by the pulverizing table 12 and pulverizing rollers 13 (hereinafter, the pulverized solid fuel will be referred to as "pulverized fuel") into particles larger than a predetermined particle size (for example, 70 to 100 μm for coal) (hereinafter, pulverized fuel exceeding the predetermined particle size will be referred to as "coarse pulverized fuel") and particles smaller than the predetermined particle size (hereinafter, pulverized fuel smaller than the predetermined particle size will be referred to as "fine pulverized fuel"). The rotary classifier 16 is given a rotational driving force by a classifier motor 18 controlled by the control unit 50, and rotates around a coal feed pipe 17, centered on a cylindrical axis (not shown) extending in the vertical direction of the housing 11. The classifying section may be a fixed classifier having a fixed hollow inverted cone-shaped casing and a plurality of fixed swirl vanes on the outer periphery of the casing instead of the blades 16a.

[0025] When the pulverized fuel reaches the rotary classifier 16, due to the relative balance between the centrifugal force generated by the rotation of the blades 16a and the centripetal force of the primary air flow, large diameter coarse pulverized fuel particles are knocked down by the blades 16a and returned to the pulverizing table 12 to be pulverized again, and the fine pulverized fuel is led to the outlet port 19 in the ceiling 42 of the housing 11. The fine pulverized fuel classified by the rotary classifier 16 is discharged together with the primary air from the outlet port 19 into the pulverized fuel supply flow path (pulverized fuel supply pipe) 120 and supplied to the burner 220 of the boiler 200.

[0026] The coal feed pipe 17 is attached so that its lower end extends vertically into the interior of the housing 11, penetrating the ceiling 42 of the housing 11, and supplies solid fuel fed from the top of the coal feed pipe 17 to the center of the grinding table 12. A coal feeder 25 is connected to the upper end of the coal feed pipe 17, and solid fuel is supplied thereto.

[0027] The coal feeder 25 is connected to the bunker 21 by a downspout 22, which is a pipe extending vertically from the lower end of the bunker 21. A valve (coal gate, not shown) for switching the discharge state of the solid fuel from the bunker 21 may be provided midway through the downspout 22. The coal feeder 25 includes a conveying unit 26 and a coal feeder motor 27. The conveying unit 26 is, for example, a belt conveyor, and conveys the solid fuel discharged from the lower end of the downspout 22 to the upper part of the coal feed pipe 17 by the driving force of the coal feeder motor 27, and then deposits it inside. The amount of solid fuel supplied to the mill 10 is controlled by a signal from the control unit 50, for example, by adjusting the movement speed of the belt conveyor of the conveying unit 26.

[0028] Normally, primary air is supplied to the inside of the mill 10 to transport pulverized fuel to the burner 220, and the pressure is higher than that of the coal feeder 25 and the bunker 21. Inside the downspout section 22 that connects the bunker 21 and the coal feeder 25, fuel is layered. This solid fuel layer ensures a sealing property (material seal) that prevents the primary air and pulverized fuel from flowing back from the mill 10 toward the bunker 21.

[0029] Biomass fuels, such as wood chips and wood pellets, have a uniform size before pulverization compared to coal. For example, before pulverization, coal is in the form of chunks measuring 2 to 50 mm, while wood pellets are cylindrical and homogeneous, measuring 6 to 8 mm in diameter and 40 mm or less in length. When coal is stacked in the downspout 22, smaller coal particles fill the gaps between larger coal particles, resulting in a densely stacked structure. On the other hand, when biomass fuel is stacked in the downspout 22, its size is uniform compared to coal, preventing the gap-filling effect of particles of different sizes, and resulting in larger gaps between the biomass fuel particles. Therefore, the primary air and pulverized fuel inside the mill 10 may pass through the gaps formed in the solid fuel layer in the downspout 22, causing a backflow from inside the mill 10 through the coal feeder 25 and the downspout 22 to the bunker 21, resulting in a decrease in pressure inside the mill 10. This is more likely when using biomass fuel than when using coal fuel. Furthermore, if the primary air and pulverized fuel flow back toward the bunker 21 and the pressure inside the mill 10 drops, various problems may occur in the stable operation of the solid fuel pulverizer 100 and the boiler 200, such as a deterioration in the transportability of the pulverized fuel inside the mill 10, the generation of dust inside the coal feeder 25 and above the bunker 21, ignition of solid fuel inside the coal feeder 25, bunker 21, or downspout section 22, and a decrease in the amount of pulverized fuel transported to the burner 220. For this reason, a rotary valve (not shown) may be provided midway along the coal supply pipe 17 connecting the coal supply machine 25 to the inside of the mill 10 to suppress the occurrence of backflow of primary air and pulverized fuel from the inside of the mill 10 through the coal supply machine 25 and downspout section 22 to the bunker 21.

[0030] The blower 30 is a device that blows primary air into the housing 11 to dry the pulverized fuel and transport it to the rotary classifier 16 . In this embodiment, the blower section 30 is equipped with a primary air fan (PAF) 31, a hot gas flow path 30a, a cold gas flow path 30b, a hot gas damper 30c, and a cold gas damper 30d in order to appropriately adjust the flow rate and temperature of the primary air blown into the inside of the housing 11.

[0031] In this embodiment, the hot gas flow path 30a supplies a portion of the air sent out from the primary air fan 31 as hot gas that has been heated by passing through an air preheater (heat exchanger) 34. A hot gas damper 30c is provided in the hot gas flow path 30a. The opening degree of the hot gas damper 30c is controlled by the control unit 50. The flow rate of the hot gas supplied from the hot gas flow path 30a is determined by the opening degree of the hot gas damper 30c.

[0032] The cold gas flow path 30b supplies a portion of the air sent out from the primary air ventilator 31 as cold gas at room temperature. A cold gas damper 30d is provided in the cold gas flow path 30b. The opening degree of the cold gas damper 30d is controlled by the control unit 50. The flow rate of the cold gas supplied from the cold gas flow path 30b is determined by the opening degree of the cold gas damper 30d.

[0033] In this embodiment, the flow rate of the primary air is the sum of the flow rate of the hot gas supplied from the hot gas flow path 30a and the flow rate of the cold gas supplied from the cold gas flow path 30b, and the temperature of the primary air is determined by the mixing ratio of the hot gas supplied from the hot gas flow path 30a and the cold gas supplied from the cold gas flow path 30b, and is controlled by the control unit 50. Furthermore, the oxygen concentration in the primary air blown from the primary air passage 110 into the housing 11 may be adjusted by, for example, introducing a portion of the combustion gas discharged from the boiler 200 by a gas recirculation fan (not shown) into the hot gas supplied from the hot gas passage 30a and mixing the same. By adjusting the oxygen concentration in the primary air, for example, when a highly ignitable (easily ignitable) solid fuel is used, it is possible to prevent the solid fuel from igniting on the path from the mill 10 to the burner 220.

[0034] In this embodiment, data measured or detected by the state detection unit 40 of the mill 10 is transmitted to the control unit 50. The state detection unit 40 of this embodiment is, for example, a differential pressure measurement means, and measures the differential pressure of the mill 10 as the differential pressure between the pressure at the portion where primary air flows from the primary air flow path 110 into the inside of the housing 11 and the pressure at the outlet port 19 where the primary air and pulverized fuel are discharged from the inside of the housing 11 to the pulverized fuel supply pipe 120. An increase or decrease in this differential pressure of the mill 10 corresponds to an increase or decrease in the amount of pulverized fuel circulating between the vicinity of the rotary classifier 16 inside the housing 11 and the vicinity of the grinding table 12 due to the classification effect of the rotary classifier 16. In other words, by adjusting the rotation speed of the rotary classifier 16 according to the differential pressure of the mill 10, the amount and particle size range of the pulverized fuel discharged from the outlet port 19 can be adjusted, so that the particle size of the pulverized fuel can be maintained within a range that does not affect the combustibility of the solid fuel in the burner 220, and an amount of pulverized fuel corresponding to the amount of solid fuel supplied to the mill 10 can be stably supplied to the burner 220 provided in the boiler 200. Furthermore, the state detection unit 40 of this embodiment is, for example, a temperature measurement means that detects the temperature of the primary air supplied to the inside of the housing 11 (mill inlet primary air temperature) and the temperature of the mixed gas of primary air and pulverized fuel at the outlet port 19 (mill outlet primary air temperature), and controls the blower unit 30 so that the respective upper limit temperatures do not exceed them. Each upper limit temperature is determined taking into consideration the possibility of ignition depending on the properties of the solid fuel. Note that, since the primary air is cooled inside the housing 11 by drying and transporting the pulverized fuel, the primary air temperature at the mill inlet is, for example, from room temperature to approximately 300°C, and the primary air temperature at the mill outlet is, for example, from room temperature to approximately 90°C.

[0035] The control unit 50 is a device that controls each part of the solid fuel pulverizer 100 . The control unit 50 may, for example, transmit a drive command to the mill motor 15 to control the rotation speed of the grinding table 12. The control unit 50, for example, transmits a drive command to the classifier motor 18 to control the rotational speed of the rotary classifier 16 to adjust the classification performance, and can stably supply to the burner 220 an amount of pulverized fuel corresponding to the amount of solid fuel supplied to the mill 10 while maintaining the particle size of the pulverized fuel within a range that does not affect the combustibility of the solid fuel in the burner 220. Furthermore, the control unit 50 can adjust the amount of solid fuel supplied to the mill 10 (amount of coal supply) by transmitting a drive command to the coal supply motor 27, for example. Furthermore, the control unit 50 can adjust the flow rate and temperature of the primary air by controlling the opening rates of the hot gas damper 30c and the cold gas damper 30d by transmitting an opening rate instruction to the blower unit 30. Specifically, the control unit 50 controls the opening rates of the hot gas damper 30c and the cold gas damper 30d so that the flow rate of the primary air supplied to the inside of the housing 11 and the temperature of the primary air at the outlet port 19 (mill outlet primary air temperature) become predetermined values ​​set corresponding to the coal feed rate for each type of solid fuel. Note that the temperature of the primary air may also be controlled by controlling the temperature at the mill inlet (mill inlet primary air temperature).

[0036] The control unit 50 is composed of, for example, a central processing unit (CPU), random access memory (RAM), read-only memory (ROM), and a computer-readable storage medium. A series of processes for implementing various functions is stored in a storage medium, for example, in the form of a program. The CPU reads the program into the RAM and executes information processing and arithmetic operations to implement various functions. The program may be pre-installed in a ROM or other storage medium, provided in a state stored in a computer-readable storage medium, or distributed via wired or wireless communication means. Examples of computer-readable storage media include magnetic disks, magneto-optical disks, CD-ROMs, DVD-ROMs, and semiconductor memories. The HDD may be replaced with a solid-state disk (SSD), for example. The configuration of the control unit 50 is not limited to the above-described configuration. For example, the hardware configuration of the control unit 50 may be configured as shown in Fig. 11. Details of the configuration shown in Fig. 11 will be described later.

[0037] Next, a description will be given of the boiler 200 that generates steam by burning the pulverized fuel supplied from the solid fuel pulverizer 100. The boiler 200 includes a furnace 210 and a burner 220.

[0038] The burner 220 is a device that burns pulverized fuel to form a flame using a mixture of pulverized fuel and primary air supplied from the pulverized fuel supply pipe 120 and secondary air supplied by heating air (outside air) sent out from a forced draft fan (FDF) 32 with an air preheater 34. The pulverized fuel is burned in the furnace 210, and the high-temperature combustion gas passes through heat exchangers (not shown) such as an evaporator, a superheater, and a coal economizer before being discharged to the outside of the boiler 200.

[0039] The combustion gas discharged from the boiler 200 undergoes predetermined treatment in environmental equipment (such as a denitration device, dust collector, and desulfurization device, not shown), and then undergoes heat exchange with primary air and secondary air in an air preheater 34. The gas is then guided to a chimney (not shown) via an induced draft fan (IDF) 33 and released into the outside air. The air heated by the combustion gas in the air preheater 34 and delivered from the primary air fan 31 is supplied to the above-mentioned hot gas flow path 30a. The water supplied to each heat exchanger of the boiler 200 is heated in a coal economizer (not shown), and then further heated in an evaporator (not shown) and a superheater (not shown) to generate high-temperature, high-pressure superheated steam, which is then sent to the steam turbine (not shown), which is the power generation section, to rotate and drive the steam turbine, which then rotates and drives a generator (not shown) connected to the steam turbine to generate electricity, thereby constituting the power generation plant 1.

[0040] Next, the details of the crushing roller 13 and the abnormality detection system will be described with reference to FIGS. First, an example of the detailed configuration of the crushing roller 13 will be described with reference to Figures 2 to 4. The crushing roller 13 is supported in the housing 11 by a journal head (support portion) 45. The journal head 45 includes a journal shaft 52 to which the crushing roller 13 is attached, a main body 56 that holds the journal shaft 52, an eccentric shaft 48 fixedly attached to the side of the main body 56, a support arm 47 attached to the top surface of the main body 56 so as to extend upward, and a protrusion 57 provided on the bottom surface of the main body 56 so as to protrude downward.

[0041] A hollow hub 51 having a substantially cylindrical shape is attached to the center of the crushing roller 13. The crushing roller 13 is attached to the tip of a journal shaft 52 via the hub 51. That is, the crushing roller 13 is attached to the journal shaft 52 via a journal bearing (roller journal bearing) 59, so that the crushing roller 13 can rotate in the circumferential direction around the journal shaft 52. The roller journal bearing 59 is, for example, a roller bearing. As will be described later, in this embodiment, an abnormality in the roller journal bearing 59 is detected. The eccentric shaft 48 has an axis that is substantially horizontal and is disposed so as to extend in the tangential direction of the circular shape of the crushing table 12. The journal head 45 is rotatable around the eccentric shaft 48, and by rotating around the eccentric shaft 48, the distance (lift amount X (see FIG. 15)) of the crushing roller 13 relative to the crushing table 12 changes.

[0042] A pressing device 46 that presses the upper end of the support arm 47 is attached to the housing 11. The pressing device 46 includes an intermediate piston 53 attached to the housing 11 so as to be movable in the longitudinal direction, and a hydraulic load unit 54 that is attached to the outer periphery of the housing 11 and presses the outer end of the intermediate piston 53. The inner end of the intermediate piston 53 contacts the outer periphery of the upper end of the support arm 47. The pressing device 46 generates a hydraulic load L1 (see FIG. 12) using the hydraulic load unit 54, and moves the intermediate piston 53 in the longitudinal direction, thereby oscillating the journal head 45 around the eccentric shaft 48. In other words, the crushing roller 13 is pressed against the crushing table 12 by the pressing device 46.

[0043] When the journal head 45 swings to a certain position around the eccentric shaft 48, the protrusion 57 abuts against the stopper 58. The stopper 58 functions as a limiting member that limits the amount of movement of the crushing roller 13 in the direction in which it presses against the crushing table 12.

[0044] Next, the abnormality detection system will be described. The abnormality detection system includes a vibration sensor 80 that detects vibrations generated in the journal head 45 due to the driving of the crushing roller 13, and a control unit (detection unit) 50 that detects abnormalities (damage, etc.) in the roller journal bearings 59 based on the vibration information detected by the vibration sensor 80.

[0045] 3 and 4, the eccentric shaft 48 is disposed so as to penetrate the housing 11. As a result, a horizontal tip end portion (installation portion) 48a of the eccentric shaft 48 is located outside the housing 11. In other words, the tip end portion 48a is exposed to the outside of the housing 11.

[0046] As shown in Fig. 3, a pedestal 81 is fixed to the end surface of the tip portion 48a. The tip portion 48a and the pedestal 81 are fixed so as not to move relative to each other. The pedestal 81 has legs extending horizontally and a vertical plate fixed to the tip of the leg. A vibration sensor 80 is fixed to the plate surface of the vertical plate. More specifically, a first sensor 80a, a second sensor 80b, and a third sensor 80c are fixed to the pedestal 81. The pedestal 81 and the first sensor 80a, the second sensor 80b, and the third sensor 80c are fixed so as not to move relative to each other. The first sensor 80a detects, for example, vibrations in the up-down direction (Y-axis direction in FIG. 4). The second sensor 80b detects, for example, vibrations in the extension direction of the eccentric shaft 48 (Z-axis direction in FIG. 4). The third sensor 80c detects vibrations in the extension direction of the journal shaft 52 (X-axis direction in FIG. 4). In FIG. 4, the eccentric shaft 48 has tip portions 48a at both ends. No. The first sensor 81a, the second sensor 80b, and the third sensor 80c may be provided at either end of the tip portion 48a.

[0047] As described above, the crushing roller 13 and other components are able to swing about the central axis of the eccentric shaft 48 (see the dashed line in FIG. 3 ). Therefore, vibrations of the roller journal bearing 59 in the vertical direction (the Y-axis direction in FIG. 4 ) are transmitted as rotational motion about the eccentric shaft 48. Therefore, it is desirable not to install a sensor for detecting vertical vibrations on the central axis of the eccentric shaft 48, and it is preferable to install the sensor on the outer periphery of the eccentric shaft 48 so that it can detect tangential vibrations. This is because vibrations are transmitted to the eccentric shaft 48 as torsional vibrations (see the arrow in FIG. 3 ). If the sensor were installed on the central axis of the eccentric shaft 48, a sensor for detecting torsional vibrations would have to be used, and it may not be possible to use the same sensor for detecting axial vibrations in other directions. In this embodiment, as shown in FIGS. 2 and 3, none of the first sensor 80a, the second sensor 80b, and the third sensor 80c are positioned on the central axis of the eccentric shaft 48.

[0048] When the vibration sensor 80 is installed at the tip 48a of the eccentric shaft 48, the distance from the roller journal bearing 59, which is the vibration source, to the vibration sensor 80 is longer than when, for example, the sensor is installed inside the crusher roller 13. This means that there is a possibility that the vibration transmitted to the vibration sensor 80 will be attenuated. If the vibration is attenuated, there is a possibility that an abnormality in the roller journal bearing 59 cannot be accurately detected, so it is preferable to take measures to attenuate the vibration.

[0049] For this reason, in this embodiment, the vibration transmission path from the roller journal bearing 59 to the vibration sensor 80 is the shortest and has a highly rigid structure. In this embodiment, as shown in Fig. 2, the vibration of the roller journal bearing 59 is transmitted via the journal shaft 52 and journal head 45 (main body 56 and eccentric shaft 48). Therefore, the joints between the parts that form these vibration transmission paths are rigid joints that do not allow relative movement between the respective parts.

[0050] In detail, the joints between the roller journal bearing 59 and the journal shaft 52, the joint between the journal shaft 52 and the journal head 45 (more specifically, the main body 56), the joint between the main body 56 and the eccentric shaft 48, and the joint between the eccentric shaft 48 and the vibration sensor 80 (more specifically, the base 81) are rigidly joined. Specific examples of rigid joining include joining by shrink fitting or taper press fitting. Rigid joining may also be achieved by manufacturing the components as a single unit, or by firmly fastening them together with a fastener.

[0051] Furthermore, in order to increase the rigidity of each of the components that form the transmission path (the journal shaft 52, the main body 56 of the journal head 45, and the eccentric shaft 48), the cross section when cut in a direction intersecting the longitudinal direction has a sufficient area. By configuring each component in this way, deformation of each component can be suppressed, making it difficult for vibrations to be attenuated due to deformation. Furthermore, each part of the transmission path from the roller journal bearing 59 to the vibration sensor 80 is made of a material with low vibration damping capacity, such as structural carbon steel or cast steel, rather than a material with high vibration damping capacity, such as cast iron. This configuration makes it possible to suppress vibration damping.

[0052] The vibration frequency that occurs when an abnormality occurs in the roller journal bearing 59 can be estimated to some extent from the structure of the roller journal bearing 59 and the rotational speed of the crusher roller 13. The natural frequency (noise) of the parts that form the vibration transmission path is set so that it does not match the vibration frequency (signal) that is expected to occur when an abnormality occurs in the roller journal bearing 59. This is to prevent problems that might occur if the natural frequency of the parts that form the vibration transmission path and the vibration frequency that occurs when an abnormality occurs in the roller journal bearing 59 match, making it impossible to determine whether the vibration waveform detected by the vibration sensor 80 is due to abnormal vibration of the roller journal bearing 59 or the natural frequency of the parts that form the vibration transmission path. The natural frequency of a component that forms the vibration transmission path may be found by calculation, or may be found experimentally by performing a hammering test on the actual component. If the natural frequency of a component that forms the vibration transmission path coincides with the vibration frequency that occurs when an abnormality occurs in the roller journal bearing 59, it is preferable to change the spring constant or mass of the component that forms the vibration transmission path to shift the natural frequency from the expected vibration frequency. If only a specific harmonic component (Nth order) coincides, that harmonic may be excluded from the evaluation.

[0053] As described above, in this embodiment, there are many components that are part of the vibration transmission path. Therefore, the vibration information detected by the vibration sensor 80 contains a lot of vibration information (noise) in addition to information about the vibration of the roller journal bearings 59. In particular, as shown in FIG. 5 , the mill 10 is disturbed by vibrations caused by the grinding of the solid fuel, and by the time the vibrations are transmitted from the roller journal bearings 59 to the vibration sensor 80, they contain a lot of large vibrations other than the vibration of the roller journal bearings 59. For this reason, it is preferable to process the received signal before the control unit 50 evaluates the vibrations. The control unit 50 of this embodiment includes a signal amplifier 91, a signal processing device 92, a signal calculation device 93, a plant control device 94, and the like. In the solid fuel pulverization apparatus 100 of this embodiment, the signal of the vibration detected by the vibration sensor 80 is amplified by the signal amplifier 91 (for example, an amplifier). The amplified signal is then processed by the signal processing device 92 to remove disturbances. The processed signal is then calculated by the signal calculation device 93 to detect an abnormality in the roller journal bearings 59. The signal calculation device 93 may also derive the degree of abnormality (degree of damage) of the roller journal bearings 59, the timing for replacing the roller journal bearings 59, and the like. The information derived by the signal calculation device 93, etc. may also be displayed on the display device 95. The signal calculation device 93 transmits the derived information to the plant control device 94, and the plant control device 94 controls various devices constituting the power plant 1, such as the mill 10, based on the received information. The control contents may also be displayed on the display device 96.

[0054] Next, an example of a signal processing method and a signal calculation method performed by the control unit 50 (signal processing device 92 and signal calculation device 93) will be described with reference to FIGS.

[0055] The control unit 50 first performs filtering. Filtering is a process for removing signals of the natural frequencies of components that form the transmission path from the vibration information detected by the vibration sensor 80, and picking up only signals in the required frequency band. Details of the filtering will be explained using FIG. 6. (a) of FIG. 6 shows the change over time in the signal value detected by the vibration sensor 80. (c) of FIG. 6 shows the natural frequencies of components that form the transmission path. (b) of FIG. 6 shows the signal value obtained by removing signals of the natural frequencies of components that form the transmission path from the vibration information detected by the vibration sensor 80. In other words, (a) is the sum of (b) and (c) of FIG. 6. Note that a signal having a frequency of vibration caused by pulverization of the solid fuel may be removed by filtering.

[0056] Next, the control unit 50 performs envelope processing (envelope processing) on ​​the filtered signal values ​​(signal values ​​shown in Figures 6(b) and 7(a)). Envelope processing is a process that removes signals due to small vibrations caused by unevenness of scratches on the rolling surface of the roller journal bearing 59 and converts them into an envelope signal that represents the outline of the scratches. By performing envelope processing, each peak of the signal value is simplified, as shown in Figure 7(b).

[0057] Next, the control unit 50 performs frequency analysis processing on the signal values ​​that have been subjected to envelope processing (signal values ​​shown in FIGS. 7(b) and 8(a)). The frequency analysis processing is, for example, a fast Fourier transform (FFT) processing, which is a processing for organizing the magnitude of the signal for each frequency. By performing the FFT processing, the distribution of the magnitude of the signal value with respect to frequency is shown as shown in FIG. 8(b).

[0058] Next, the control unit 50 performs a process of superimposing the frequency (specific frequency) of vibrations generated when the roller journal bearing 59 is damaged and its integral multiples of harmonic components on the signal values ​​(signal values ​​shown in FIGS. 8(b) and 9(a)) after FFT processing. Note that this specific frequency is a numerical value specific to the bearing, and its theoretical value can be calculated from the bearing dimensions (diameters of the inner ring, outer ring, and rolling elements) and the rotational speed. More specifically, this process derives the average values ​​of the signal values ​​for the frequency differences X1 and X2 in FIG. 9(a). This process results in a distribution of the signal values ​​relative to the frequency difference, as shown in FIG. 9(b). In this embodiment, the frequency near the frequency difference X2 is considered to be an abnormal frequency of the roller journal bearing 59. Therefore, in the example of FIG. 9(b), the signal value of the frequency difference X2 is large, so it can be determined that an abnormality has occurred in the roller journal bearing 59. In this way, the control unit 50 (signal processing device 92 and signal calculation device 93) performs signal processing and calculation. Note that the signal processing and calculation methods are merely examples and are not limited to the methods described above. For example, if it is determined that the noise contained in the vibration information detected by the vibration sensor 80 is sufficiently small, the filtering process and the envelope process may be omitted.

[0059] Next, an example of a method for deriving the degree of abnormality (degree of damage) of the roller journal bearing 59 performed by the control unit 50 (signal processing device 92 and signal calculation device 93) will be described. Basically, the further the roller journal bearing 59 reaches its end of life (i.e., the more severe the abnormality), the greater the vibration of a specific frequency (the frequency of vibration generated when the roller journal bearing 59 is abnormal) and its integral multiple harmonic components. The threshold value (how large the vibration must be before it breaks) is evaluated as follows:

[0060] Normally, abnormalities (damage) in roller journal bearings 59 progress gradually as follows. Below, the degree of abnormality is explained by dividing it into four stages, from lowest to highest: "Incipient Damage," "Early Damage," "Intermediate Damage," and "Late Damage." In the early damage stage, vibrations increase in the frequency range of 10 kHz or higher. At this time, extremely small scratches appear on the rolling surface of the roller journal bearing 59, but these are only discernible to the naked eye as differences in gloss. In the early damage stage, vibrations increase in the frequency range of several kHz. At this time, transfer marks appear on the rolling surface of the roller journal bearing 59. In the intermediate damage stage, vibrations increase in the frequency range of several tens of Hz to 1 kHz. At this time, initial flaking has occurred on the rolling surface of the roller journal bearing 59. In the later damage stage, vibrations increase across all frequency ranges. At this time, clear flaking has occurred on the rolling surface of the roller journal bearing 59.

[0061] In this way, as the degree of abnormality progresses, the frequency range of the detected vibration signal shifts to the lower frequency side. Therefore, by performing frequency analysis on the vibration signal and processing the vibrations of a specific frequency and its harmonic components in each frequency range, if an increase in vibration of an abnormal frequency in the frequency range is detected, it can be determined that the damage has progressed to a degree corresponding to the frequency range. The threshold value for determining whether vibration has increased is preferably set based on the specifications of the device, between 0.1 and 10 G in the case of vibration acceleration, but for general structures, the value specified in ISO-10816 or JIS-B-0906 may also be used.

[0062] The status of the roller journal bearing 59 may be displayed on the display devices 95, 96, etc. depending on the progression of the abnormality. Specifically, for example, in the early stage, "Normal, please prepare a defensive spare part." may be displayed. In the early stage of damage, "Initial damage, please purchase a spare part." may be displayed. In the intermediate stage of damage, "Intermediate damage, please plan for replacement." In the later stage of damage, "Later stage of damage, please replace the roller journal bearing." may be displayed.

[0063] According to this embodiment, the following advantageous effects are achieved. In this embodiment, the vibration sensor 80 is provided in the journal head 45. This makes it less likely that vibrations generated in the grinding roller 13 will be transmitted to the vibration sensor 80 than, for example, when the vibration sensor 80 is provided inside the grinding roller 13. This therefore makes it possible to prevent malfunction of the vibration sensor 80 due to vibrations of the grinding roller 13. Furthermore, the vibration sensor 80 is provided on the tip 48a of the eccentric shaft 48 located outside the housing 11 of the journal head 45. This makes the vibration sensor 80 less susceptible to the effects of pulverized solid fuel and high-temperature gas (air, etc.) inside the housing 11 of the mill 10, thereby preventing malfunction of the vibration sensor 80. In this way, the vibration sensor 80 is less likely to malfunction, thereby improving its reliability. Furthermore, the vibration sensor 80 is provided at the tip 48a of the eccentric shaft 48 located outside the housing 11. This allows access to the vibration sensor 80 without stopping the operation of the mill 10 or disassembling the housing 11 or the grinding roller 13. This simplifies the replacement or addition of the vibration sensor 80 when the vibration sensor 80 needs to be replaced due to a malfunction or maintenance, or when a vibration sensor 80 is added to an existing mill. Furthermore, the mill 10 can be operated even during replacement or addition work, thereby improving the operating rate.

[0064] In this embodiment, the control unit 50 detects an abnormality in the roller journal bearing 59 based on the vibration detected by the vibration sensor 80. When the crushing roller 13 crushes the solid fuel, the crushing roller 13 vibrates. The vibration generated in the crushing roller 13 is transmitted from the crushing roller 13 to the journal head 45 via the roller journal bearing 59. Therefore, if an abnormality occurs in the roller journal bearing 59, the vibration transmitted to the journal head 45 changes. Therefore, an abnormality in the roller journal bearing 59 can be detected.

[0065] The frequency of vibrations generated when the crushing rollers 13 crush the solid fuel and the natural frequency of the transmission path from the roller journal bearings 59 to the vibration sensor 80 do not vary depending on the state (normal or abnormal) of the roller journal bearings 59. In this embodiment, frequency components that do not vary depending on the state of the roller journal bearings 59 are removed from the vibration information detected by the vibration sensor 80. This improves the accuracy of detecting abnormalities in the roller journal bearings 59.

[0066] In this embodiment, the control unit 50 performs a process (frequency analysis) to organize the signal magnitude for each frequency of the vibration information detected by the vibration sensor 80. This makes it possible to more accurately detect an abnormality in the roller journal bearing 59.

[0067] In this embodiment, the control unit 50 detects the degree of progression of the abnormality in the roller journal bearing 59 based on information on vibrations detected by the vibration sensor 80. As the abnormality (e.g., damage) in the roller journal bearing 59 progresses, the vibration of the journal head 45 changes. This allows the control unit 50 to detect the degree of progression of the abnormality in the roller journal bearing 59.

[0068] In this embodiment, the journal head 45 and the roller journal bearing 59 are joined so as not to move relative to each other. Furthermore, the journal head 45 and the vibration sensor 80 are joined so as not to move relative to each other. As a result, the information from the roller journal bearing 59 is less likely to change at the joint between the journal head 45 and the roller journal bearing 59 and at the joint between the journal head 45 and the vibration sensor 80. Therefore, the information from the roller journal bearing 59 can be properly detected by the vibration sensor 80. As a result, an abnormality in the roller journal bearing 59 can be detected more accurately.

[0069] [Variations] Next, a modification of this embodiment will be described. The location of the vibration sensor 80 is not limited to the tip 48a of the eccentric shaft 48, but may be any location near the roller journal bearing 59, outside the housing 11 of the mill 10, and where attenuation of vibration transmission is small. For example, as shown by the dashed line in Figure 2, in a structure in which the base end of the journal shaft 52 (the end opposite the end where the crushing roller 13 is provided) is located outside the housing 11 of the mill 10, the vibration sensor 80 may be provided at the base end of the journal shaft 52.

[0070] Furthermore, if a single mill 10 is provided with multiple crushing rollers 13 and multiple roller journal bearings 59, it is preferable to install a vibration sensor 80 on each crushing roller 13. This is because the damage status may differ for each crushing roller 13. Alternatively, instead of installing a vibration sensor 80 on each crushing roller 13, the vibration sensor 80 may be installed only on a representative crushing roller 13. In this case, it is desirable to take preventive measures, such as replacing all roller journal bearings 59 as soon as a minor abnormality is detected, to prevent damage to the roller journal bearings 59 from spreading to an abnormality throughout the entire mill 10.

[0071] Furthermore, when two or more roller journal bearings 59 are installed on one roller, bearings with different specifications may be used so that the specific frequencies generated when the bearings are damaged are different, and it may be possible to estimate which roller journal bearing 59 is damaged from the frequency difference detected by the vibration sensor 80.

[0072] In the above embodiment, the vibration sensor 80 is used to detect abnormalities in the roller journal bearings 59, but the sensor used to detect abnormalities in the roller journal bearings 59 is not limited to a vibration sensor (acceleration sensor). For example, a speed sensor, a displacement sensor, a strain gauge, or an acoustic sensor may be used.

[0073] The vibration sensor 80 may be installed so as to be easily replaceable. It is also desirable that the vibration sensor 80 be installed so as to be temporarily removable during maintenance of the mill 10.

[0074] Furthermore, it is preferable that the vibration sensor 80 be installed so as to be able to detect vibrations in the X-axis, Y-axis, and Z-axis directions (see FIG. 4 ) generated by the roller journal bearing 59, but any of these may be omitted as necessary. In this embodiment, as described above, the X-axis direction is the extension direction of the journal shaft 52, the Y-axis direction is the up-down direction, and the Z-axis direction is the extension direction of the eccentric shaft 48. The vibration sensor 80 may detect vibrations in only one direction, or may detect vibrations in multiple directions as in this embodiment. If the vibration sensor 80 is capable of detecting vibrations in at least two different directions, it can detect various types of vibrations, thereby improving the accuracy of detection of abnormalities in the roller journal bearing 59 by the control unit 50. It is more preferable that the two different directions are perpendicular to each other. Furthermore, when roller journal bearings 59 typically bear a load on their lower side, i.e., the crushing section side, scratches on the rolling surface are transmitted as vibrations. For example, when vibration sensor 80 is used, vibrations due to bearing damage occur as vertical displacements. Therefore, the vibrations are transmitted as vertical vibrations along journal shaft 52, are turned 90° by journal head 45, and are transmitted as torsional vibrations (vibrations displaced in the X and Y axes) to vibration sensor 80 at tip 48a of eccentric shaft 48, where they are detected. Therefore, the sensor that detects vibrations in the Z axis direction (second sensor 80b) is less important than the sensors that detect vibrations in the X and Y axes (first sensor 80a and third sensor 80c). Therefore, if vibration sensor 80 is to be omitted, second sensor 80b may be omitted first. The outputs from each sensor may be calculated separately, or the values ​​may be added together along the way.

[0075] Furthermore, the vibration sensor 80 may be provided with a waterproof, dustproof, explosion-proof, etc. However, if a cover is provided, it is preferable that the cover does not affect the detection of the signal. Furthermore, the wiring from the vibration sensor 80 to the control unit 50 may be a shielded cable, an optical cable, or the like that is less susceptible to external noise.

[0076] The anomaly detection system may be a permanent monitoring instrument that performs measurements continuously, or it may be a spot measurement system that performs measurements temporarily as needed. When using spot measurements, it is preferable to set the timing of the measurements appropriately. For example, it may be performed when the roller journal bearing 59 is first used (when it is new) to obtain basic data, and then data may be obtained when the remaining life of the roller journal bearing 59 has decreased after a certain period of use. However, with spot measurements, there is a possibility that a sudden deterioration in the condition of the roller journal bearing 59 may not be detected when measurements are not being taken, so it is preferable to install the anomaly detection system permanently.

[0077] Furthermore, when performing spot measurements, it is preferable to perform the measurements under the same operating conditions (type of solid fuel used, amount of solid fuel supplied, etc.) of the mill 10 as much as possible. This reduces variations due to differences in the operating conditions of the mill 10, and improves the accuracy of bearing abnormality detection. In the case of permanent installation, it is preferable to configure the system so that data under each operating condition is accumulated and an abnormality detection threshold for each operating condition is automatically set.

[0078] Furthermore, the order in which the control unit 50 applies signal processing may be changed as appropriate, taking into account the operating state of the mill 10, as long as the purpose is not deviated from. Furthermore, additional processing may be added in addition to the processing described above. For example, if the natural frequency of a component that is the vibration transmission path matches only a specific harmonic component (Nth order) among the frequencies of vibrations that occur when an abnormality occurs in the roller journal bearings 59, processing may be performed to exclude signals in the frequency range of that harmonic from the evaluation.

[0079] The threshold for bearing abnormality detection may be a standard value estimated from past operating data. The Mahanobis Taguchi System (MT) method may also be used to identify trends and determine abnormality detection. Because the vibration information signal changes depending on the operating conditions of the mill 10, it is preferable to change the abnormality detection threshold depending on the operating conditions of the mill 10.

[0080] Furthermore, if the control unit 50 determines that an abnormality has occurred, information about the abnormality detection may be displayed on the display device 96 of the plant control device 94. This may also be used as a trigger to change the operating conditions of the mill 10 (for example, by reducing the amount of fuel supplied), to perform a detailed inspection of the roller journal bearings 59, to replace them, or to arrange for parts, etc. The information may not be displayed only on the plant control device 94, but may also be sent by email or the like to a registered information terminal such as a personal computer or smartphone. Alternatively, the information may only be displayed on-site. If the abnormality detection system is a system independent of the plant control device 94, modifications to the plant control device 94 can be omitted.

[0081] Furthermore, if the control unit 50 determines that an abnormality has occurred, the system may communicate this information to the manufacturer (the manufacturer and supplier of the mill 10). When the manufacturer receives the abnormality determination information, it may make appropriate suggestions (such as detailed diagnosis, parts purchase, or adjustment of construction schedule) to the user (the user of the mill 10). The information may also be communicated to a third party other than the manufacturer or user, such as a bearing manufacturer to adjust the bearing production quota, or a maintenance company to use the information to secure a maintenance budget.

[0082] [Second embodiment] Next, a second embodiment of the present disclosure will be described. This embodiment differs from the first embodiment in that the control unit 50 is equipped with a remaining life estimation system. Since other points are the same as those in the first embodiment, the same components are assigned the same reference numerals and detailed descriptions thereof will be omitted. The remaining life estimation system according to this embodiment is configured, for example, as follows.

[0083] The control unit 50 estimates the remaining life of the roller journal bearings 59. In other words, the control unit 50 functions as a remaining life estimation system for the roller journal bearings 59 of the crushing rollers 13 that crush the solid fuel between them and the crushing table 12. Note that the function of the remaining life estimation system may be provided in a control device separate from the control unit 50.

[0084] FIG. 10 is a diagram showing an example of the hardware configuration of the control unit 50 according to this embodiment. 10, the control unit 50 is a computer system (calculating system) and includes, for example, a CPU 111, a ROM (Read Only Memory) 121 for storing programs and the like executed by the CPU 111, a RAM (Random Access Memory) 130 that functions as a work area when each program is executed, a hard disk drive (HDD) 140 as a mass storage device, and a communication unit 150 for connecting to a network, etc. These units are connected via a bus 180.

[0085] The control unit 50 may also include an input unit such as a keyboard and a mouse, and a display unit such as a liquid crystal display device for displaying data.

[0086] The storage medium for storing the programs executed by the CPU 111 is not limited to the ROM 121. For example, it may be other auxiliary storage devices such as a magnetic disk, a magneto-optical disk, or a semiconductor memory.

[0087] A series of processing steps for realizing the various functions described below are recorded in the HDD 140 or the like in the form of a program, and the CPU 111 reads this program into the RAM 130 or the like and executes information processing and arithmetic operations to realize the various functions described below. The program may be pre-installed in the ROM 121 or other storage medium, provided in a state stored in a computer-readable storage medium, or distributed via wired or wireless communication means. Examples of computer-readable storage media include magnetic disks, magneto-optical disks, CD-ROMs, DVD-ROMs, and semiconductor memories. The HDD 140 may be replaced with a solid-state disk (SSD) or the like.

[0088] 11 is a functional block diagram showing functions related to remaining life estimation provided in the control unit 50. As shown in FIG.

[0089] The acquisition unit 62 acquires measured values ​​of information relating to the load on the crushing roller 13 and measured values ​​of information relating to the inclination angle of the crushing roller 13 relative to the crushing table 12. The acquisition unit 62 acquires measured values ​​of information relating to the load on the crushing roller 13 and information relating to the inclination angle of the crushing roller 13 relative to the crushing table 12, which are important for reflecting the actual operating state in estimating the remaining life of the roller journal bearings 59.

[0090] The information regarding the load on the crushing roller 13 is information regarding the load L2 received by the crushing roller 13 from the crushing table 12, as shown in FIG. 12. The load L2 from the crushing table 12 is a force (load) received by the crushing roller 13 when the crushing roller 13 is pressed against the solid fuel supplied to the upper surface of the crushing table 12 to be crushed. In other words, it is a force received by the crushing roller 13 in a direction perpendicular to the contact surface between the crushing table 12 and the crushing roller 13, or the closest facing surface when the gap between the crushing roller 13 and the crushing table 12 is set to be minimum. The load L2 from the crushing table 12 acts along an axis AX1 parallel to the rotation axis of the crushing table 12 (for example, in the direction of the rotation axis). Note that the shape of the crushing table 12 in FIG. 12 is an example and is not limited to this shape.

[0091] In this embodiment, a case will be described in which the hydraulic load L1 in the hydraulic loading unit 54 is acquired as information regarding the load on the crushing roller 13, that is, the added load in the pressing device 46 (the pressing force that presses the crushing roller 13 against the crushing table 12 via the solid fuel to be crushed). The hydraulic load (added load) L1 is a parameter controlled when controlling the pressing of the crushing roller 13 against the crushing table 12, and an actual value is measured by an installed sensor and output to the acquisition unit 62. The sensor may be, for example, a pressure sensor such as a load cell or a pressure sensor. Note that the information regarding the load on the crushing roller 13 is not limited to the hydraulic load (added load) L1, and any parameter related to the load on the crushing roller 13 can be applied. For example, the load on the crushing roller 13 or the load on the roller journal bearing 59 may be directly measured and acquired by a sensor.

[0092] The information relating to the tilt angle of the crushing roller 13 relative to the crushing table 12 is information relating to the roller tilt angle θ, as shown in Fig. 13 (a partially enlarged vertical cross-sectional view showing the roller tilt angle). The roller tilt angle θ is the tilt of the crushing roller 13 relative to the crushing table 12, and is the angle formed between an axis AX1 in the direction of the rotation axis of the crushing table 12 (or an axis parallel to the rotation axis) and an axis AX3 (vertical plane) perpendicular to the rotation axis AX2 of the crushing roller 13.

[0093] In this embodiment, the lift amount X of the crushing roller 13 is used as information regarding the inclination angle of the crushing roller 13 relative to the crushing table 12. The lift amount X of the crushing roller 13 is the distance between the crushing table 12 and the crushing roller 13. The lift amount X is the distance caused by the presence of solid fuel to be crushed between the crushing table 12 and the crushing roller 13. Because the crushing roller 13 rotates around the eccentric shaft 48, the lift amount X is the distance between the crushing table 12 and the crushing roller 13 when the crushing roller 13 moves up and down relative to the eccentric shaft 48. In this embodiment, the lift amount X is acquired by, for example, a gap sensor as shown in FIG. 15. The lift amount X may be acquired by a linear movement sensor, a capacitance distance sensor, a laser distance sensor, or the like. In FIG. 7, a measurement bar 71 and a gap sensor 72 are provided relative to the eccentric shaft 48. The measurement bar 71 rotates in accordance with the rotation of the eccentric shaft 48 (the rotation of the crushing roller 13). The gap sensor 72 is fixed in position and measures the distance between the gap sensor 72 and the measurement bar 71. 14 and 15, the ratio of the lift amount X to the distance L between the central axis (AX3) of the crushing roller 13 and the eccentric shaft 48 is equal to the ratio of the length l of the measuring bar 71 in the gap sensor 72 to the gap value x. Therefore, the lift amount X can be calculated from the gap sensor 72 using the following equation (1).

[0094]

number

[0095] In equation (1), L and l are design values, and x can be obtained from the gap sensor 72, so that the lift amount X can be calculated. The lift amount X may be measured by calculating it from the operation amount of the pressing device 46, for example, the movement amount of the intermediate piston 53, or by measuring the lift amount X directly if it is possible to measure it directly.

[0096] The acquisition unit 62 may acquire the lift amount X, or may acquire the gap value x which is the output of the gap sensor 72. Furthermore, if the movement amount of the crushing roller 13 is limited by the protrusion 57 and the stopper 58 and a gap is provided between the crushing roller 13 and the crushing table 12, the 0 (zero) point of the gap value x may be set as the point where the gap between the crushing roller 13 and the crushing table 12 is smallest, and similarly, the 0 (zero) point of the gap value x of the gap sensor 72 may be set as the point where the distance between the gap sensor 72 and the measuring bar 71 is smallest.

[0097] In this embodiment, the lift amount X of the crushing roller 13 is used as information regarding the inclination angle of the crushing roller 13 relative to the crushing table 12. However, any information regarding the roller inclination angle θ can be used without being limited to the lift amount X of the crushing roller 13. The roller inclination angle θ may also be directly measured and acquired using a sensor or the like. As will be described later, in this embodiment, the roller inclination angle θ is calculated from the lift amount X of the crushing roller 13, and the thrust load Ls and radial load Lr are calculated and used for remaining life estimation. However, when the lift amount X of the crushing roller 13 is acquired, the thrust load Ls and radial load Lr may be calculated and the remaining life estimation may be performed without calculating the roller inclination angle θ. In this case, the acquisition unit 62 acquires a measured value of information regarding the load applied to the crushing roller 13 and a measured value of information regarding the lift amount X of the crushing roller 13 relative to the crushing table 12. The information regarding the lift amount X of the crushing roller 13 relative to the crushing table 12 can be used without being limited to the lift amount X, as long as it is information regarding the lift amount X.

[0098] The estimation unit 63 estimates the remaining life of the roller journal bearing 59 based on the information acquired by the acquisition unit 62. Specifically, the estimation unit 63 calculates the radial load Lr and thrust load Ls applied to the roller journal bearing 59, and estimates the remaining life of the roller journal bearing 59 based on the radial load Lr and the thrust load Ls.

[0099] FIG. 12 is a diagram (partially enlarged longitudinal cross-sectional view) showing the relationship between the loads around the crushing roller 13. As shown in FIG. 12, the crushing roller 13 is pressed against the crushing table 12 by a hydraulic load L1, and therefore a load L2 from the crushing table 12 is applied to the crushing roller 13. Solid fuel to be crushed may be present between the crushing roller 13 and the crushing table 12. The load L2 from the crushing table 12 is also applied to the roller journal bearing 59 via the crushing roller 13. By decomposing the load L2 received by the roller journal bearing 59 into a radial component and a thrust component, the radial load Lr and thrust load Ls on the roller journal bearing 59 can be calculated. The estimation unit 63 estimates the remaining life of the roller journal bearing 59 based on the radial load Lr and the thrust load Ls. Note that a known method can be used to estimate the life of the roller journal bearing 59 using the radial load Lr and the thrust load Ls.

[0100] Specifically, the estimation unit 63 receives the hydraulic load L1 and lift amount X acquired by the acquisition unit 62. Alternatively, the estimation unit 63 may receive the gap value x and calculate the lift amount X using the above-described calculation. The estimation unit 63 calculates the load L2 received by the roller journal bearing 59 from the grinding table 12 based on the input hydraulic load L1. The crushing roller 13 is pressed against the grinding table 12 via the solid fuel being crushed based on the hydraulic load L1, so there is a correlation between the hydraulic load L1 and the load L2 from the grinding table 12. Therefore, the estimation unit 63 can calculate the load L2 from the grinding table 12 from the hydraulic load L1. If the load L2 from the grinding table 12 can be directly acquired by the acquisition unit 62 using a measuring device using various sensors, the acquired load L2 from the grinding table 12 may be used. When calculating the load L2 from the hydraulic load L1, the weight of the grinding roller 13 and the members supporting it may be taken into account in addition to the hydraulic load L1.

[0101] Then, the estimation unit 63 calculates the roller tilt angle θ based on the input lift amount X. The roller tilt angle θ is calculated by the following equation (2).

[0102]

number

[0103] As shown in Figure 13, in equation (2), θ0 is the roller tilt reference angle, which is the roller tilt angle θ when the lift amount X is 0 (zero) (i.e., the crushing roller 13 and the crushing table 12 are in contact, or the gap between the crushing roller 13 and the crushing table 12 is at its smallest). Δθ is the amount of change in the roller tilt angle θ with respect to the roller tilt reference angle, and Δθ is the value of the arctangent function of the ratio of the lift amount X to the distance L. In other words, when the lift amount X is small, the roller tilt angle θ becomes large, and when the lift amount X becomes large, the roller tilt angle θ becomes small.

[0104] In this way, when the load L2 from the rotary table 12 and the roller tilt angle θ are calculated in the estimation unit 63, the thrust load Ls and radial load Lr are calculated as shown in the relationship in Fig. 14. The thrust load Ls is calculated by multiplying the load from the rotary table 12 by sin(θ), and the radial load Lr is calculated by multiplying the load from the rotary table 12 by cos(θ).

[0105] In this way, the estimation unit 63 calculates the thrust load Ls and radial load Lr applied to the roller journal bearing 59, and estimates the remaining life based on the thrust load Ls and the radial load Lr. Various methods can be applied to estimate the remaining life as long as they are based on the thrust load Ls and the radial load Lr.

[0106] Next, an example of the remaining life estimation process performed by the control unit 50 will be described with reference to Fig. 16. Fig. 16 is a flowchart showing an example of the procedure for the remaining life estimation process according to this embodiment. The flow shown in Fig. 16 is executed, for example, when an instruction to start remaining life estimation is given by an operator or the like. Note that the remaining life estimation process may also be executed periodically even without an instruction to start by an operator or the like.

[0107] First, the actual measured values ​​of the hydraulic load L1 and the lift amount X are obtained (S101).

[0108] Next, the roller tilt angle θ is calculated based on the lift amount X (S102).

[0109] Next, the radial load Lr and thrust load Ls applied to the roller journal bearing 59 are calculated (S103).

[0110] Next, the radial load Lr and the thrust load Ls are used to estimate the remaining life of the roller journal bearing 59 (S104). Note that, in estimating the remaining life, information other than the radial load Lr and the thrust load Ls (for example, design values ​​of the roller journal bearing 59) can be used depending on the estimation method.

[0111] Next, the effect of the above-mentioned remaining life estimation process will be described with reference to Fig. 17. Fig. 17 shows the change in the load on the power plant and the load on the journal bearings over operating time, and the change in the remaining life over operating time. Fig. 17 shows, as a reference example, a case in which the remaining life is estimated assuming that the maximum load is continuously applied as a design value.

[0112] In the reference example, when it is assumed that the load of the power plant 1 is operated at rated load (for example, 100% load), it is assumed that the load applied to the roller journal bearing 59 will be maximum in proportion to the load of the power plant 1. Therefore, the remaining life decreases linearly with the operating time, and it is estimated that maintenance will be required at operating time T2 in Figure 17.

[0113] In contrast, in this embodiment, since the load applied to the grinding roller 13 is sequentially measured as the hydraulic load L1, the load applied to the roller journal bearing 59 corresponding to the operating state of the actual power plant 1 can be obtained. As shown by the load (broken line graph) applied to the actual roller journal bearing 59 in FIG. 17, since it may be lower than the maximum load, when the remaining life is estimated in consideration of the measured value of the roller inclination angle θ, the reduction of the remaining life with respect to the operating time becomes gradual compared with the reference example. Particularly, in the period Ta in FIG. 17, since the load applied to the roller journal bearing 59 is low, the consumption of the remaining life is small. Note that the period Ta changes according to the operating state and is not limited to the period shown in FIG. 17.

[0114] For example, in FIG. 17, if the current point is taken as the operating time T1, it is also possible to estimate the operating time T3 as the time when maintenance is required by linearly extending the transition of the remaining life for a predetermined period from the present.

[0115] According to the remaining life estimation of this embodiment, it is possible to estimate the remaining life of the roller journal bearing 59 with higher accuracy according to the actual operating state. Therefore, it is possible to estimate the time when maintenance is required more accurately compared with the reference example (the operating time is T2 < T3), and it is possible to operate the mill 10 more efficiently.

[0116] In this embodiment, the remaining life is estimated using the measured values ​​of the hydraulic load L1 and the lift amount X. However, the remaining life may also be estimated using the measured value of the rotational speed of the roller journal bearing 59 (the rotational speed of the grinding roller 13). In this case, the acquisition unit 62 acquires the measured value of information related to the rotational speed of the roller journal bearing 59, and the estimation unit 63 estimates the remaining life by taking into account the measured value of information related to the rotational speed of the roller journal bearing 59. For example, if the grinding roller 13 slips relative to the pulverized solid fuel on the grinding table 12, the rotational speed of the roller journal bearing 59 may decrease or stop. Therefore, a rotational speed sensor may be installed to detect the actual rotational speed of the roller journal bearing 59, and the measured value of the rotational speed may be taken into account when estimating the remaining life. By taking into account the measured value of the rotational speed of the roller journal bearing 59, the estimation accuracy can be improved compared to when estimating the remaining life assuming that the rotational speed of the roller journal bearing 59 is constant. The sensor may be, for example, a rotational position sensor such as a rotary encoder, a rotational speed sensor, or an acceleration sensor that detects changes in the direction of gravity or centrifugal force. Measured information may be transmitted to the outside of the mill 10 by wired communication means or by some kind of wireless communication means.

[0117] In this embodiment, the remaining life is estimated using the measured values ​​of the hydraulic load L1 and the lift amount X. However, the remaining life may also be estimated using the state of the lubricant in the roller journal bearings 59. In this case, the acquisition unit 62 acquires measured values ​​of information related to the state of the lubricant in the roller journal bearings 59, and the estimation unit 63 estimates the remaining life by taking into account the measured values ​​of information related to the state of the lubricant in the roller journal bearings 59. For example, if fine particles of the pulverized solid fuel are mixed into the lubricant in the roller journal bearing 59 box of the grinding roller 13, the life of the roller journal bearings 59 may be significantly shortened. For this reason, a sensor that detects the state of the lubricant (e.g., contamination, deterioration, etc.) may be installed in the roller journal bearing 59 box, and the influence of the lubricant state may be taken into account when estimating the remaining life. Taking into account the state of the lubricant can further improve the accuracy of the remaining life estimation. The majority of contamination of the lubricant is caused by the intrusion of fine particles resulting from pulverized solid fuel through the seal portion (oil seal portion) of the crushing roller 13. Furthermore, since the intrusion of fine particles is often caused by insufficient seal air pressure in the seal portion, a sensor may be installed to detect changes in seal air pressure, and the effect of insufficient seal air pressure may be taken into account when estimating the remaining life.

[0118] As described above, the remaining life estimation system, solid fuel pulverizer, remaining life estimation method, and remaining life estimation program according to this embodiment acquire information about the load acting on the crushing roller 13 and information about the tilt angle of the crushing roller 13 relative to the crushing table 12 as measured values, and estimate the remaining life of the roller journal bearings 59. This makes it possible to take into account the impact on the remaining life estimation of fluctuations in the operating state of the mill 10 equipped with the crushing roller 13, thereby improving the accuracy of the remaining life estimation. Furthermore, since the direction of the load acting on the roller journal bearings 59 can be estimated from the lift amount X of the crushing roller 13 relative to the crushing table 12, the remaining life of the roller journal bearings 59 can be estimated using the lift amount X of the crushing roller 13.

[0119] Furthermore, by estimating the remaining life more accurately, maintenance (replacement, etc.) of the roller journal bearings 59 can be performed at a more appropriate time. In other words, the roller journal bearings 59 can be used for a longer period of time, reducing the frequency of maintenance of the mill 10. This reduces maintenance costs. Furthermore, the availability of the mill 10 and the power plant 1 can be improved.

[0120] [Variation 1] Next, a remaining life estimation system, a solid fuel pulverization device, a remaining life estimation method, and a remaining life estimation program according to a modified example of the second embodiment of the present disclosure will be described. In this modification, the remaining life estimation system, the solid fuel pulverization device, the remaining life estimation method, and the remaining life estimation program according to this modification will be described below, focusing on the differences from the second embodiment.

[0121] The control unit 50 in this modification includes a prediction unit 64, as shown in FIG. The prediction unit 64 predicts the future transition of the remaining life from the transition of the remaining life estimated by the estimation unit 63, based on a database in which the operating state of the mill 10 and the remaining life transition characteristics corresponding to the operating state are previously accumulated. The remaining life estimation characteristics are information indicating the characteristics of the remaining life that transition depending on the operating state, and specifically, are curved characteristics (or may be linear) such as those shown in A, B, and C of FIG. 19. That is, the database stores past and current operating information of the mill 10. The database may store past and current operating data of the mill 10 whose life is to be estimated, or may store past operating data of other mills 10 with similar configurations. In addition to actual operating data, virtually simulated data may also be stored in the database. The database may be provided in the control unit 50 (storage unit) or in a separate device. The operating conditions include at least one of the following: the type of solid fuel (coal type information), the amount of solid fuel supplied (coal feed rate), information about the load on the grinding roller 13 (hydraulic load), the rotation speed (classifier rotation speed) of the classifier (rotary classifier 16) installed in the mill 10, and the differential pressure between the gas flowing into the mill 10 and the gas exhausted from the mill 10 (this is the differential pressure inside the mill 10 and serves as an indicator of the load condition of the mill 10. For example, it occurs between the atmosphere above and below the grinding table 12). Note that the operating conditions are not limited to the above and can include any parameter that affects the life of the roller journal bearings 59. Furthermore, if the change in remaining life with respect to operating time between similar operating conditions matches within ±10%, and more preferably within ±5%, excluding operating information (estimated remaining life) that is judged to be obviously erratic, the data of similar operating conditions may be prioritized and determined to be similar.

[0122] Specifically, the prediction unit 64 refers to the database to select data on operating conditions similar to the operating conditions of the mill 10 for which the remaining life is to be estimated, and selects and acquires remaining life transition characteristics corresponding to the data on similar operating conditions. The data on similar operating conditions refers to data on operating conditions that are estimated to have a similar degree of remaining life impact to the operating conditions of the mill 10 for which the remaining life is to be estimated. For example, if the type of solid fuel is used as the operating condition, an operating condition that includes a solid fuel that is estimated to have a similar effect in terms of remaining life impact to the solid fuel of the mill 10 for which the remaining life is to be estimated is considered to be a similar operating condition. Priorities for similarity determination may be set for each parameter of the operating conditions, and similarity determination may be performed for parameters with higher priorities (e.g., the type of solid fuel).

[0123] Fig. 19 shows an example in which remaining life transition characteristics under similar operating conditions are selected for the mill 10 for which remaining life is to be estimated. Fig. 19 shows an example in which characteristics A, B, and C are selected as remaining life transition characteristics. Fig. 19 also shows remaining life estimation results E1 (first estimation result), E2 (second estimation result), and En (nth estimation result) for the mill 10 for which remaining life is to be estimated.

[0124] The prediction unit 64 identifies, from the selected remaining life transition characteristics (A, B, C), the remaining life transition characteristic (A, B, C) that has a transition characteristic similar to the transition characteristic E based on the remaining life estimation results from E1 to En of the mill 10 being the target of remaining life estimation. In the example of FIG. 19 , the transition characteristic from E1 to En is similar to the characteristic B, so the characteristic B is identified. Therefore, it is estimated that the remaining life characteristic of the mill 10 being the target of remaining life estimation will transition in the future with respect to operating time, similar to the characteristic B, and will reach the end of life time Tb. By referencing the transition characteristic E in this way to a database from the past or the present, it is possible to predict the future remaining life transition taking into account the operating status of the mill 10, thereby enabling more accurate remaining life estimation. The transition characteristic E of the remaining life estimation results of the mill 10 being the target of remaining life estimation may be the transition characteristic from the time of completion to the present, or the transition characteristic for a predetermined period from the present to the past, or may be the transition characteristic selected from a period in which the operating status changed significantly (for example, the type of solid fuel changed).

[0125] Note that, as in the example of FIG. 19 , even if the transition characteristic of the remaining life estimation result for the mill 10 being the subject of remaining life estimation does not completely correspond to the selected remaining life transition characteristic, a similar transition characteristic may be selected from the selected remaining life transition characteristics. Furthermore, if there is no transition characteristic similar to the transition characteristic of the remaining life estimation result for the mill 10 being the subject of remaining life estimation in the past or current database among the selected remaining life transition characteristics, a prediction may be made based on the selected remaining life transition characteristic. For example, in FIG. 19 , if the transition characteristic of the remaining life estimation result for the mill 10 being the subject of remaining life estimation is located between characteristic A and characteristic B in the ratio of the difference between the characteristic A side and the characteristic B side, the future remaining life transition of the mill 10 being the subject of remaining life estimation may be predicted based on characteristic A and characteristic B. In this case, for example, the midpoint between characteristic A and characteristic B is generated by proportionally dividing the difference between the characteristic A side and the characteristic B side, and the remaining life transition prediction is performed.

[0126] The processing by the prediction unit 64 (selection of similar operating conditions in the database, selection of remaining life transition characteristics having transition characteristics similar to the transition characteristics of the remaining life estimation results for the mill 10 that is the subject of remaining life estimation in the selected remaining life transition characteristics, and prediction of future remaining life transitions based on the selected remaining life transition characteristics) may be performed using a preset algorithm, or may be appropriately performed using AI.

[0127] As described above, the remaining life estimation system, solid fuel pulverizer, remaining life estimation method, and remaining life estimation program according to this embodiment are based on a database in which operating states and remaining life transition characteristics are associated, and thereby future transitions in remaining life can be predicted from the transitions in remaining life estimated by the estimation unit 63. This allows for more accurate prediction of future transitions in remaining life, enabling maintenance (e.g., replacement) of the roller journal bearings 59 to be performed at more appropriate times. This means that the roller journal bearings 59 can be used for a longer period, reducing the frequency of maintenance of the mill 10. This, in turn, reduces maintenance costs. Furthermore, the availability of the mill 10 and the power plant 1 can be improved.

[0128] [Variation 2] Next, a remaining life estimation system, a solid fuel pulverization device, a remaining life estimation method, and a remaining life estimation program according to a modified example of the second embodiment of the present disclosure will be described. In this modification, a maintenance plan is created based on the estimated remaining life. The remaining life estimation system, solid fuel pulverization device, remaining life estimation method, and remaining life estimation program according to this modification will be described below, focusing on the differences from the second embodiment and modification 1 of the second embodiment.

[0129] The control unit 50 in this modification includes a planning unit 65, as shown in FIG. The planning unit 65 makes a maintenance plan based on the estimated remaining lifespan. Specifically, the planning unit 65 makes a maintenance plan by determining when in the future the lifespan will be completely consumed from the remaining lifespan estimated by the estimating unit 63 and the remaining lifespan estimated by the predicting unit 64. Note that, since the remaining lifespan can be estimated more accurately as described above, it becomes possible to make a plan with an appropriate margin before the lifespan is completely consumed.

[0130] The planning unit 65, for example, creates a maintenance plan a predetermined period before the estimated end of life. The predetermined period is set based on the period required to perform maintenance in a safe and efficient process, such as the period from arranging for roller journal bearings 59 to replacing them. The maintenance plan includes, for example, at least one of the maintenance timing, an operating plan for adjusting the maintenance timing, and load sharing adjustment among multiple mills 10.

[0131] The maintenance timing is the timing (recommended timing) for replacing the roller journal bearing 59, which is set based on the estimated remaining life. The maintenance timing is set, for example, by adding a predetermined margin to the estimated end of life.

[0132] An operating plan for adjusting the maintenance timing is an operating plan for the mill 10, and is intended to adjust the maintenance timing. For example, if the maintenance timing has already been set and is later than the estimated end of life, an operating plan for extending the life is planned. Specifically, this includes changing the type of solid fuel or reducing the fineness of the solid fuel to be pulverized. By optimizing the operating conditions, it is possible to extend the life through a safer and more efficient process and perform maintenance at an appropriate time. Note that if the preset maintenance timing is earlier than the estimated end of life, the remaining life may be effectively utilized by planning an operating plan that increases the load so as not to increase the remaining life.

[0133] Load sharing adjustment among multiple mills 10 refers to appropriately adjusting the load sharing among multiple mills 10. For example, adjustment of the load sharing among each mill 10 is planned in order to synchronize the maintenance timing of multiple mills 10 or to set the timing in stages (for example, to set equal intervals between maintenance for multiple mills 10). For example, if one mill 10 among multiple mills 10 reaches the end of its life sooner than the other mills 10, the load on that mill 10 can be reduced and the load on the other mills 10 increased to bear the load, thereby adjusting the end of the life of the multiple mills 10 to coincide.

[0134] Fig. 21 shows an example of a system related to maintenance planning. As shown in Fig. 21, remaining life estimation information for the mill 10 is collected in an information collection system 101 on the user side, and a server 102 on the equipment manufacturer side acquires the information collected in the collection system, makes a plan in a planning system 103, and makes a proposal to the user. Note that Fig. 21 illustrates an example in which the planning unit 65 is provided on the equipment manufacturer side as the planning system 103, but it may also be provided on the user's side of the solid fuel pulverizer.

[0135] As described above, the remaining life estimation system, solid fuel pulverizer, remaining life estimation method, and remaining life estimation program according to this embodiment allow for maintenance planning based on the estimated remaining life, allowing for maintenance to be scheduled with ample time to be scheduled. This improves the availability of the mill 10 and the power plant 1.

[0136] Next, an example of a method for using the abnormality detection system for the roller journal bearing 59 and the remaining life estimation system in combination will be described with reference to FIG. Figure 22 shows the estimated remaining life and abnormality level (degree of damage progression) of the roller journal bearing 59 over time. The dashed line indicates the change in the remaining life of the roller journal bearing 59 calculated under a set load. The solid line indicates the change in the remaining life calculated from the actual load using the remaining life estimation system. The dashed line indicates the magnitude of the abnormal signal (a signal of a bearing abnormality frequency in a specified frequency range) detected by the abnormality detection system. t1 indicates that the remaining life calculated under a set load is zero (i.e., the design life). The difference between the remaining life calculated under the set load and the remaining life calculated from the actual load using the remaining life estimation system at t1 (remaining life difference D) indicates the margin for replacing the bearing at the design life. t3 indicates the time when the roller journal bearing 59 becomes unusable due to damage. In other words, it indicates the actual life. t2 is the replacement timing determined using the detection results of the abnormality detection system. In this way, by using the anomaly detection system and the remaining life estimation system together, it is possible to continue using the roller journal bearing 59 even in areas with little margin, compared to when only the remaining life estimation system is used.

[0137] This embodiment provides the following advantageous effects. Generally, an abnormality detection system can detect an increase in vibration of the roller journal bearing 59, but it is not possible to determine a clear threshold for the increase that will cause the roller journal bearing 59 to become unusable unless an actual machine is used until the roller journal bearing 59 becomes unusable and the signal transition up to that point is confirmed. However, because it takes a long time to conduct a test until the bearing is damaged on an actual machine, there was a problem that an abnormality detection system alone would not be able to extend the life of the roller journal bearing 59. On the other hand, by using both the roller journal bearing 59 anomaly detection system and the remaining life estimation system as in this embodiment, the roller journal bearing 59 can be monitored for steady life consumption by the remaining life estimation system and for abnormality detection by the abnormality detection system. This makes it possible to extend the life of the roller journal bearing 59 while ensuring its reliability.

[0138] In detail, as described above, the remaining life estimation system evaluates the remaining life of the roller journal bearings 59 from operational information of the crusher roller 13 (for example, the load acting on the crusher roller 13 and the rotational speed of the crusher roller 13). In other words, it visualizes the "fatigue life" of the roller journal bearings 59. This is an evaluation of the "calculated life of the roller journal bearings 59." However, the actual life of the roller journal bearing 59 is determined not only by the fatigue life but also by many other factors. For example, it is possible that impurities in the lubricating oil may cause scratches on the rolling surfaces, shortening the life of the roller journal bearing 59. On the other hand, the anomaly detection system indirectly detects damage to the rolling surfaces of the roller journal bearing 59 that occurs over time through use, for example, vibration. In other words, while the remaining life estimation system evaluates the calculated life of the roller journal bearing 59, the anomaly detection system evaluates the actual life of the roller journal bearing 59. By using both of these methods in combination, it becomes possible to evaluate the life of the roller journal bearing 59, taking into account not only the calculated "fatigue life" but also "influences other than fatigue life" caused by, for example, contaminants in the lubricating oil. Furthermore, the fatigue life can be evaluated using both methods, enabling more accurate maintenance of the roller journal bearing 59. However, by performing evaluations using both methods, there is a possibility that a discrepancy may occur between the calculated lifespan based on lifespan monitoring and the actual lifespan based on abnormality detection. In such cases, for example, it is possible that the actual lifespan is ahead of the calculated lifespan, or that factors other than fatigue life are dominant. In such cases, the results may be reflected in the maintenance policy, for example, by increasing the frequency of lubricating oil changes or changing the oil viscosity to reduce impurities.

[0139] The present disclosure is not limited to the above-described embodiments, and various modifications can be made without departing from the spirit of the present disclosure. The solid fuel used is not limited to that disclosed herein, and may be coal, biomass fuel, petroleum coke (PC), etc. Furthermore, these solid fuels may be used in combination.

[0140] The abnormality detection system, the solid fuel pulverizer, and the abnormality detection method described in the above-described embodiments can be understood, for example, as follows. An abnormality detection system according to one embodiment of the present disclosure is an abnormality detection system for a roller journal bearing (59) that is housed inside a housing (11) that forms the outer shell of a solid fuel pulverizing device (100) and rotatably supports a crushing roller (13) that crushes solid fuel between the housing (11) and a crushing table (12), and includes: a detection unit (80) that supports the crushing roller (13) via the roller journal bearing (59) and is provided on an installation portion (48a) located outside the housing (11) of a support portion (45) attached to the housing (11), and that detects information generated in the support portion (45) by the rotation of the crushing roller (13); and a detection unit (50) that detects an abnormality in the roller journal bearing (59) based on the information detected by the detection unit (80).

[0141] In the above configuration, the detection unit is provided on the support part. This makes it possible to reduce the transmission of vibrations generated by the grinding roller to the detection unit compared to, for example, a case where the detection unit is provided inside the grinding roller. Therefore, it is possible to reduce the occurrence of failure of the detection unit due to vibrations of the grinding roller. Furthermore, the detection unit is provided on an installation part located outside the housing of the support part. This makes it less susceptible to the effects of high-temperature gas (air, etc.) inside the housing of the mill, thereby reducing the occurrence of failure of the detection unit. In this way, it is possible to reduce the likelihood of failure of the detection unit, thereby improving the reliability of the detection unit. The detector is mounted on an installation section located outside the housing of the support section. This allows access to the detector without stopping the operation of the solid fuel pulverizer or disassembling the housing or pulverizer rollers. This simplifies the process of replacing or adding a detector when replacing the detector due to a malfunction or maintenance, or when adding a sensor to an existing solid fuel pulverizer. Furthermore, the solid fuel pulverizer can be operated even during replacement or addition work, improving operating efficiency.

[0142] In addition, in an abnormality detection system according to one aspect of the present disclosure, the detection unit (80) detects information on vibrations of the support unit (45), and the detection unit (50) detects an abnormality in the roller journal bearing (59) based on the information on vibrations detected by the detection unit (80).

[0143] In the above configuration, the detection unit detects an abnormality in the roller journal bearing based on the vibration detected by the detection unit. When the crushing roller crushes the solid fuel, the crushing roller vibrates. The vibration generated in the crushing roller is transmitted from the crushing roller to the support unit via the roller journal bearing. Therefore, if an abnormality occurs in the roller journal bearing, the vibration transmitted to the support unit changes. Therefore, an abnormality in the roller journal bearing can be detected.

[0144] Furthermore, an abnormality detection system according to an aspect of the present disclosure detects information on vibrations in multiple directions.

[0145] In the above configuration, various types of vibrations can be detected, and therefore the detection accuracy of the detection unit in detecting abnormalities in the roller journal bearings can be improved.

[0146] In addition, in the abnormality detection system according to one aspect of the present disclosure, the detection unit (50) performs processing on the vibration information detected by the detection unit (80) to remove components having the frequency of vibration generated when the crushing roller (13) crushes the solid fuel and / or components having the natural frequency of the transmission path from the roller journal bearing (59) to the detection unit (80).

[0147] The frequency of vibrations generated when the crushing roller crushes the solid fuel and the natural frequency of the transmission path from the roller journal bearing to the detector do not vary depending on the state (normal or abnormal) of the roller journal bearing. The above configuration eliminates such frequencies that do not vary depending on the state of the roller journal bearing. Therefore, the accuracy of detecting abnormalities in the roller journal bearing can be improved.

[0148] In the abnormality detection system according to an aspect of the present disclosure, the detection unit (50) performs processing to determine the signal magnitude for each frequency based on information about vibration detected by the detection unit (80).

[0149] In the above configuration, the detection unit performs processing to sort the signal magnitude for each frequency of the vibration information detected by the detection unit, thereby enabling more accurate detection of an abnormality in the roller journal bearing.

[0150] In addition, in the abnormality detection system according to one aspect of the present disclosure, the detection unit (50) detects the degree of progression of the abnormality in the roller journal bearing (59) based on information about the vibration detected by the detection unit (80).

[0151] In the above configuration, the detection unit detects the degree of progression of the abnormality in the roller journal bearing based on information about the vibration detected by the detection unit. As the abnormality (e.g., damage) in the roller journal bearing progresses, the vibration of the support unit changes. This allows the detection unit to detect the degree of progression of the abnormality in the roller journal bearing.

[0152] In addition, a solid fuel pulverizing device according to one embodiment of the present disclosure includes a housing (11) forming an outer shell, a pulverizing table (12) housed inside the housing (11), a pulverizing roller (13) housed inside the housing (11) and pulverizing solid fuel between the pulverizing table (12), a support part (45) attached to the housing (11) and supporting the pulverizing roller (13), a roller journal bearing (59) that supports the pulverizing roller (13) rotatably relative to the support part (45), and an abnormality detection system described in any one of the above.

[0153] In addition, in a solid fuel pulverization device according to one embodiment of the present disclosure, the support portion (45) and the roller journal bearing (59) are connected so as not to move relative to each other, and the support portion (45) and the detection portion (80) are connected so as not to move relative to each other.

[0154] In the above configuration, the support portion and the roller journal bearing are joined so as not to move relative to each other. Furthermore, the support portion and the detection portion are joined so as not to move relative to each other. This makes it difficult for information from the roller journal bearing to change at the joints between the support portion and the roller journal bearing and between the support portion and the detection portion. Therefore, information from the roller journal bearing can be properly detected by the detection portion. This allows for more accurate detection of abnormalities in the roller journal bearing. The support part and the roller journal bearing may be joined by, for example, shrink fitting or press fitting so as to prevent relative movement. The support part and the detection part may be joined by, for example, bolts so as to prevent relative movement. Furthermore, "joined so as to prevent relative movement" means that they are joined to the extent that vibrations of the roller journal bearing can be properly detected by the detection part provided on the support part, and of course some relative movement is permitted.

[0155] In addition, a solid fuel pulverization device according to one aspect of the present disclosure includes an abnormality detection system as described above and a remaining life estimation system that estimates the remaining life of the roller journal bearings based on operating information of the pulverization rollers, and estimates the remaining life of the roller journal bearings based on information derived by the abnormality detection system and information derived by the remaining life estimation system.

[0156] As configured above, by using the roller journal bearing anomaly detection system and remaining life estimation system together, the roller journal bearings can be monitored for steady life consumption by the remaining life estimation system and for abnormality detection by the abnormality detection system, thereby ensuring the reliability of the roller journal bearings and extending their lifespan.

[0157] Furthermore, an abnormality detection method according to one aspect of the present disclosure is a method for detecting an abnormality in a roller journal bearing (59) that is accommodated inside a housing (11) forming an outer shell and rotatably supports a crushing roller (13) that crushes solid fuel between the roller journal bearing (59) and a crushing table (12), and the roller journal bearing (59) is provided on an installation portion (48a) located outside the housing (11) of a support portion (45) that supports the crushing roller (13) via the roller journal bearing (59) and is attached to the housing (11). R The method includes a detection step of detecting, by a detection unit (80), information generated on the support part (45) by the rotation of the crushing roller (13), and a detection step of detecting an abnormality in the roller journal bearing (59) based on the information detected by the detection unit (80). [Explanation of symbols]

[0158] 1. Power Plant 10 Mill (grinding section) 11. Housing 12 Grinding Table 13 Crushing roller 14 Reducer (drive transmission part) 15 Mill motor (drive unit) 16 Rotary classifier (classifying section) 16a blade 17 Coal feed pipe (fuel supply part) 18 Classifier motor 19 Exit Port 21 Bunka (storage section) 22 Downspout 25 Coal feeding machine (fuel supply machine) 26 Conveyor 27 Coal feeder motor 30 Blower (Carrier Gas Supply) 30a Hot gas flow path 30b Cold gas flow path 30c Thermal Gas Damper 30d Cold Gas Damper 31 Primary Air Ventilator (PAF) 32 Forced draft fan (FDF) 33 Induced Draft Fan (IDF) 34 Air preheater (heat exchanger) 40 Status detection unit (temperature detection means, differential pressure detection means) 41 Bottom part 42 Ceiling 45 Journal head (support part) 46 Pressing device (crushing load applying part) 47 Support Arm 48 Eccentric shaft 48a Tip part (installation part) 50 control unit (detection unit) 51 Hub 52 Journal shaft 53 Intermediate piston 54 Hydraulic load section 56 Main Unit 57 Protrusion 58 Stopper 59 Journal bearing (roller journal bearing) 62 Acquisition Department 63 Estimation part 64 Prediction Department 65 Planning Department 71 Measuring Bar 72 Gap sensor 80 Vibration sensor (detection part) 80a First sensor 80b Second sensor 80c 3rd sensor 81 Pedestal 91 Signal Amplifier 92 Signal Processing Device 93 Signal calculation device 94 Plant Control Device 95 Display device 96 Display device 100 Solid fuel crusher 101 Information Aggregation System 102 Server 103 Planning System 110 Primary air flow path (carrier gas flow path) 111 CPU 120 Pulverized fuel supply passage (pulverized fuel supply pipe) 121 ROM 130 RAM 140 HDD 150 Communications Department 180 Bus 200 boiler 210 Furnace 220 Burner (combustion device)

Claims

1. 1. A roller journal bearing abnormality detection system that is housed inside a housing that forms the outer shell of a solid fuel pulverizer and rotatably supports a crushing roller that crushes solid fuel between the roller and a crushing table, comprising: a detection unit that is provided on an installation part located outside the housing of a support part that supports the crushing roller via the roller journal bearing and is attached to the housing, and that detects information generated on the support part by rotation of the crushing roller; a detection unit that detects an abnormality in the roller journal bearing based on the information detected by the detection unit, the detection unit detects information about vibration of the support unit, the detection unit detects an abnormality in the roller journal bearing based on information about the vibration detected by the detection unit, The detection unit is an anomaly detection system that performs processing on the vibration information detected by the detection unit to remove components having the frequency of vibrations generated when the crushing roller crushes the solid fuel and / or components having the natural frequency of the transmission path from the roller journal bearing to the detection unit.

2. The abnormality detection system according to claim 1 , wherein the detection unit detects information on vibrations in a plurality of directions.

3. 3. The anomaly detection system according to claim 1, wherein the detection unit performs processing to obtain a signal magnitude for each frequency from information about vibrations detected by the detection unit.

4. 4. The abnormality detection system according to claim 1, wherein the detection unit detects the degree of progression of the abnormality in the roller journal bearing based on information about vibrations detected by the detection unit.

5. 5. The abnormality detection system according to claim 1, wherein the detection unit is provided on the installation portion located outside the housing of an eccentric shaft of the support portion attached to the housing, the eccentric shaft rotating about a central axis to change the distance of the crushing roller relative to the crushing table.

6. 1. A roller journal bearing abnormality detection system that is housed inside a housing that forms the outer shell of a solid fuel pulverizer and rotatably supports a crushing roller that crushes solid fuel between the roller and a crushing table, comprising: a detection unit that is provided on an installation part located outside the housing of a support part that supports the crushing roller via the roller journal bearing and is attached to the housing, and that detects information generated on the support part by rotation of the crushing roller; a detection unit that detects an abnormality in the roller journal bearing based on the information detected by the detection unit, The abnormality detection system is such that the detection unit is provided on the installation part located outside the housing of an eccentric shaft of the support part attached to the housing that rotates around the central axis to change the distance of the grinding roller relative to the grinding table.

7. 7. The abnormality detection system according to claim 5, wherein the detection unit is provided so as not to be positioned on the central axis of the eccentric shaft.

8. a housing forming an outer shell; a grinding table housed inside the housing; a crushing roller housed inside the housing and configured to crush the solid fuel between the crushing roller and the crushing table; a support portion attached to the housing and supporting the crushing roller; a roller journal bearing that rotatably supports the crushing roller relative to the support portion; A solid fuel pulverizer comprising: an abnormality detection system according to any one of claims 1 to 7.

9. The support portion and the roller journal bearing are coupled so as not to move relative to each other, 9. The solid fuel pulverizer according to claim 8, wherein the support portion and the detection portion are connected so as not to move relative to each other.

10. An anomaly detection system according to any one of claims 1 to 7; a remaining life estimation system that estimates a remaining life of the roller journal bearing based on operation information of the crushing roller, The solid fuel pulverizer estimates the remaining life of the roller journal bearings based on the information derived by the abnormality detection system and the information derived by the remaining life estimation system.

11. 1. A method for detecting an abnormality in a roller journal bearing that is accommodated inside a housing forming an outer shell and rotatably supports a grinding roller that grinds solid fuel between the roller and a grinding table, comprising: a detecting step of detecting information generated on the support part by rotation of the crushing roller using a detecting unit provided on an installation part located outside the housing of a support part that supports the crushing roller via the roller journal bearing and is attached to the housing; a detection step of detecting an abnormality in the roller journal bearing based on the information detected by the detection unit, the detection unit detects information about vibration of the support unit, the detecting step detects an abnormality in the roller journal bearing based on information about vibrations detected by the detecting unit, The detection process is an abnormality detection method that performs processing on the vibration information detected by the detection unit to remove components having the frequency of vibration generated when the crushing roller crushes the solid fuel and / or components having the natural frequency of the transmission path from the roller journal bearing to the detection unit.

12. 1. A method for detecting an abnormality in a roller journal bearing that is accommodated inside a housing forming an outer shell and rotatably supports a grinding roller that grinds solid fuel between the roller and a grinding table, comprising: a detecting step of detecting information generated on the support part by rotation of the crushing roller using a detecting unit provided on an installation part located outside the housing of a support part that supports the crushing roller via the roller journal bearing and is attached to the housing; a detection step of detecting an abnormality in the roller journal bearing based on the information detected by the detection unit, An abnormality detection method in which the detection unit is provided at the installation portion located outside the housing of an eccentric shaft of the support portion attached to the housing that rotates around the central axis to change the distance of the grinding roller relative to the grinding table.

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