Solid fuel pulverizing device, boiler facility, and solid fuel pulverizing device operation method

Abstract

To provide a solid fuel pulverizing device that can be adjusted so that pulverized fuel is uniformly supplied to each pulverized fuel supply line.SOLUTION: A solid fuel pulverizing device includes: a rotary classification device 16 provided inside a housing 11 having a plurality of blades 16a extending in a vertical direction and arranged aligned in a circumferential direction around the central axis for classifying pulverized fuel that is guided together with carrier gas; a plurality of nozzles 84 that eject gas to an enclosed region 16X that is enclosed by the plurality of blades 16a disposed aligned in the circumferential direction; and a plurality of pulverized fuel supply lines for supplying the pulverized fuel that is classified by the rotary classification device 16 and has a predetermined particle diameter or less to a boiler from the enclosed region 16X via a plurality of outlet ports 19 of the housing 11 together with the carrier gas.SELECTED DRAWING: Figure 4

Description

[Technical Field]

[0001] The present disclosure relates to a solid fuel pulverizer and boiler equipment, and a method for operating a solid fuel pulverizer. [Background technology]

[0002] Solid fuel such as biomass fuel or coal is pulverized into fine powder having a particle size of a predetermined size or less in a pulverizer (mill), and then supplied to a combustion device of a boiler via a pulverized fuel supply line. The mill is a facility that crushes solid fuel fed onto a crushing table by pinching it between the crushing table and crushing rollers, and then selects pulverized fuel (solid fuel crushed into fine powder) with a particle size of a predetermined size or less. The pulverized fuel is transported from the mill to the boiler together with carrier gas (primary air) through multiple pulverized fuel supply lines. A boiler is a facility that generates combustion gas by burning transported pulverized fuel in a combustion device, and generates steam by heat exchange between the generated combustion gas and water. In a thermal power plant, steam generated in a boiler is used to rotate a steam turbine, which in turn rotates a generator connected to the steam turbine, thereby generating electricity.

[0003] In order to stabilize combustion in the burners provided in the boiler, it is preferable that the pulverized fuel is supplied uniformly to each pulverized fuel supply line. For example, Patent Document 1 describes that an annular member supported by blades and a support member is provided inside a rotary separator to improve the uniform distribution of powder fluid into pulverized coal pipes. [Prior art documents] [Patent documents]

[0004] [Patent Document 1] Japanese Patent Application Laid-Open No. 2016-112519 Summary of the Invention [Problem to be solved by the invention]

[0005] However, with the structure of Patent Document 1, it is expected that it may be difficult to make fine adjustments to uniformly supply the pulverized fuel to each pulverized fuel supply line. Therefore, it is desired to be able to make adjustments so that the pulverized fuel is uniformly supplied to each pulverized fuel supply line.

[0006] The present disclosure has been made in consideration of the above circumstances, and aims to provide a solid fuel pulverizing device and boiler equipment, as well as an operating method for a solid fuel pulverizing device, that can uniformly supply the amount of pulverized fuel to each pulverized fuel supply line. [Means for solving the problem]

[0007] In order to solve the above problems, the solid fuel pulverizer, boiler equipment, and method of operating the solid fuel pulverizer of the present disclosure employ the following measures.

[0008] A solid fuel pulverizer according to one aspect of the present disclosure includes a housing, a rotary table disposed inside the housing and rotating about a central axis extending in a vertical direction, pulverizing rollers disposed inside the housing that grip solid fuel between the rotary table and the solid fuel to pulverize it into pulverized fuel, a carrier gas supply line that supplies a carrier gas for transporting the pulverized fuel into the interior of the housing, a rotary classifier disposed inside the housing and having a plurality of blades extending in the vertical direction and arranged in a circumferential direction around the central axis, the rotary classifier classifying the pulverized fuel introduced together with the carrier gas, a plurality of ejection units that eject gas into an enclosed area surrounded by the plurality of blades arranged in a circumferential direction, and a plurality of pulverized fuel supply lines that supply the pulverized fuel having a particle size of less than a predetermined size, classified by the rotary classifier, together with the carrier gas, from the enclosed area to a boiler via a plurality of outlet ports of the housing.

[0009] A boiler facility according to one aspect of the present disclosure includes a solid fuel pulverizer and a boiler that burns pulverized fuel in a combustion device to generate steam.

[0010] In addition, a method for operating a solid fuel pulverization device according to one embodiment of the present disclosure is a method for operating a solid fuel pulverization device, which adjusts at least one of the direction of the gas ejected from each of the ejection sections and the flow rate of the gas ejected from each of the ejection sections. [Effects of the Invention]

[0011] According to the present disclosure, it is possible to provide a method for operating a solid fuel pulverizer that can adjust the supply of pulverized fuel to each pulverized fuel supply line uniformly, as well as a solid fuel pulverizer and boiler equipment. [Brief explanation of the drawings]

[0012] [Figure 1] 1 is a schematic configuration diagram of a power plant equipped with a solid fuel pulverizer according to an embodiment of the present disclosure. [Figure 2] FIG. 2 is a schematic diagram showing the main part of the solid fuel pulverizer of FIG. 1. [Figure 3] FIG. 3 is a partially enlarged view of the schematic configuration diagram of FIG. 2. [Figure 4] FIG. 4 is a plan view of FIG. 3. [Figure 5] FIG. 10 is a plan view showing an example of a jetting direction. DETAILED DESCRIPTION OF THE INVENTION

[0013] Hereinafter, a method for operating a solid fuel pulverizer, a solid fuel pulverizer, and a boiler facility according to an embodiment of the present disclosure will be described with reference to the drawings. In the following explanation, "upper" in terms such as "top" and "top surface" refers to the part above the vertical. Similarly, "lower" refers to the part below the vertical. However, the vertical direction is not precise and may include errors.

[0014] [Configuration of solid fuel pulverizer] The power plant 1 includes a boiler facility including a solid fuel pulverizer 100 and a boiler 200, and a power generation section (not shown).

[0015] The solid fuel pulverizer 100 is a device that generates pulverized fuel by pulverizing solid fuel such as coal or biomass fuel, and supplies the pulverized fuel to a burner 220 (combustion device) of a boiler 200. 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, etc. However, biomass fuel is not limited to the examples given here.

[0016] In the power plant 1 shown in FIG. 1, the number of solid fuel pulverizers 100 is one. However, the power plant 1 may include a plurality of solid fuel pulverizers 100. For example, the power plant 1 may include the solid fuel pulverizers 100 in a number corresponding to the number of burners 220 included in one boiler 200.

[0017] As shown in Figures 1 and 2, the solid fuel pulverizer 100 includes a mill 10 (pulverizer), a fuel supply unit having a bunker 21 and a fuel supply device 20, a blower unit 30 (carrier gas supply unit), a carrier gas supply line 110, a plurality of pulverized fuel supply lines 120, and a control unit 50.

[0018] The mill 10 is equipment for pulverizing solid fuel. The mill 10 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 both coal and biomass fuel. The mill 10 includes a housing 11, a grinding table 12 (rotary table), grinding rollers 13, a reducer 14, a mill motor 15 (drive unit) connected to the reducer 14 and driving the grinding table 12 to rotate, a rotary classifier 16 (rotary classifier unit), a fuel supply pipe 17, and a classifier motor 18 that drives the rotary classifier 16 to rotate.

[0019] The housing 11 is formed in a cylindrical shape extending in the vertical direction, and is a case that houses the crushing table 12, the crushing rollers 13, the rotary classifier 16, and a part of the fuel supply pipe 17 (a part including the lower end). The shape of the housing 11 may be changed as appropriate depending on the shape of the components to be housed. For example, if the outer shape of the rotary classifier 16 is large, the diameter of the housing 11 may be increased only around the rotary classifier 16.

[0020] A reducer 14 is installed near the bottom surface 41 of the housing 11. A mill motor 15 is connected to the reducer 14. The milling table 12 is configured to rotate around a rotation axis L1 (central axis) by a driving force transmitted from a mill motor 15 via a reducer .

[0021] The crushing table 12 is a portion that is formed into a substantially circular shape when viewed from above in the direction of the rotation axis L1, and is disposed so that its central portion faces the lower end of the fuel supply pipe 17. As shown in FIG. 2, the upper surface of the grinding table 12 forms a smoothly inclined surface that is higher in the center, becomes lower as it approaches the periphery from the center, and then becomes higher again. The shape of the upper surface of the rotary table 12 may be changed as appropriate. For example, the upper surface of the rotary table 12 may be an inclined surface that is low in the center and becomes higher as it approaches the periphery from the center.

[0022] A fuel supply pipe 17 is attached to the center of the ceiling portion 42 of the housing 11. The fuel supply pipe 17 is a part that supplies solid fuel guided from the fuel supply section into the inside of the housing 11, and is arranged vertically at the center position of the housing 11, with the part including the lower end being located inside the housing 11. The fuel supply pipe 17 supplies solid fuel toward the center of the upper surface of the grinding table 12 . The crushing table 12 sandwiches the supplied solid fuel in a biting portion 70 formed between the crushing table 12 and the crushing roller 13 .

[0023] The crushing roller 13 is a rotating body that crushes the solid fuel supplied onto the crushing table 12 from the fuel 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 and 2 show 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, spaced apart by an angle of 120 degrees around the rotation axis L1. 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 central axis of rotation of the crushing table 12. The crushing roller 13 is configured to be able to swing and displace up and down by the journal head 45. Therefore, the crushing roller 13 can move closer to or away from the upper surface of the crushing table 12. In other words, the crushing roller 13 can swing and displace freely, increasing or decreasing the distance between it and the upper surface of the crushing table 12. When the crushing table 12 rotates 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, the crushing roller 13 receives a rotational force from the crushing table 12 and rotates together with the solid fuel.

[0024] When solid fuel is supplied from the fuel supply pipe 17, the solid fuel is pressed and crushed in the biting portion 70 formed between the crushing roller 13 and the crushing table 12, forming a fuel layer 72 on the upper surface of the crushing table 12. The force with which the crushing roller 13 presses the solid fuel at this time is called the "crushing load."

[0025] A support arm 47 of the journal head 45 is accommodated in the housing 11 and is supported by a support shaft 48 that extends in the horizontal direction. The support arm 47 supports the crushing roller 13 so that it can swing about a support shaft 48. The swinging crushing roller 13 has a component of displacement in the up and down direction.

[0026] A pressing device 49 is provided at the upper end of the support arm 47 on the vertically upper side. The pressing device 49 is fixed to the housing 11 . The pressing device 49 applies a crushing load to the crushing roller 13 via the support arm 47 etc. so that the crushing roller 13 is pressed against the crushing table 12 . The crushing load is applied, for example, by a hydraulic cylinder (not shown) that operates by the pressure of hydraulic oil supplied from a hydraulic device (not shown) installed outside the mill 10. Alternatively, the crushing load may be applied by the repulsive force of a spring (not shown). The method of supporting the crushing roller 13 and the method of applying the crushing load are not limited to these. For example, the support shaft 48 of the crushing roller 13 may be directly pressed by a hydraulic cylinder (not shown).

[0027] When solid fuel is fed into the center of the grinding table 12 from the fuel supply pipe 17, the centrifugal force generated by the rotation of the grinding table 12 guides the solid fuel to the outer periphery of the grinding table 12, where it is pinched between the grinding table 12 and the grinding rollers 13 and crushed. The pulverized solid fuel is blown upward by a carrier gas (hereinafter referred to as "primary air") introduced from a carrier gas inlet 11a (inlet) of the housing 11 connected to a carrier gas supply line 110, and is introduced into a rotary classifier 16.

[0028] An outlet (not shown) is provided on the outermost periphery of the grinding table 12 or on the part of the housing 11 facing the outer peripheral surface of the grinding table 12, which allows the primary air flowing in from the carrier gas inlet 11a to flow out into the space above the grinding table 12. A swirl vane (not shown) is installed at the outlet, and applies a swirling force to the primary air blown out from the outlet. The primary air given a swirling force by the swirl vane becomes an airflow with a swirling velocity component, and transports the solid fuel pulverized on the pulverizing table 12 (hereinafter referred to as "pulverized fuel") to the rotary classifier 16 located above in the housing 11. The swirl blades may be installed on the grinding table 12 and rotate together with the grinding table 12, or may be installed on the housing 11.

[0029] The pulverized fuel having a particle size larger than a predetermined particle size is classified by the rotary classifier 16 or falls without reaching the rotary classifier 16, returns to the pulverizing table 12, and is pulverized again between the pulverizing table 12 and the pulverizing roller 13.

[0030] The rotary classifier 16 is a device that classifies pulverized fuel into particles larger than a predetermined particle size (hereinafter, pulverized fuel larger than a predetermined particle size will be referred to as "coarse pulverized fuel") and particles smaller than a predetermined particle size (hereinafter, pulverized fuel smaller than a predetermined particle size will be referred to as "fine pulverized fuel"). As shown in FIGS. 1 and 2, the rotary classifier 16 is provided in the upper part of the interior of the housing 11, has an inverted conical or cylindrical outer shape, and defines an enclosed area 16X therein. As shown in FIGS. 2 and 3, the rotary classifier 16 is provided with a plurality of blades 16a extending in the vertical direction at its outer periphery. As shown in Fig. 4, the blades 16a are provided at predetermined intervals around the central axis of the rotary classifier 16. Specifically, the blades 16a are provided at equal angular intervals on an imaginary circle C1 centered on the central axis. Here, the central axis of the rotary classifier 16 coincides with the rotation axis L1. The gaps between the blades 16a form flow paths for introducing a mixture of pulverized fuel (arrow A1) and primary air (arrow A2) into the enclosed region 16X. The surrounded region 16X is a region surrounded by the blades 16a arranged on the circle C1 and is a region inside the blades 16a in the radial direction relative to the central axis. Note that the surrounded region 16X may include at least a portion of the flow passages between the blades 16a. These blades 16a are connected to a common frame to form the rotary classifier 16 as an integrated structure having an inverted conical or cylindrical outer shape. The rotary classifier 16 is rotationally driven by a classifier motor 18 controlled by the control unit 50. The rotary classifier 16 rotates around a fuel supply pipe 17, centering on a cylindrical axis (not shown) extending in the up-down direction of the housing 11.

[0031] The pulverized fuel that reaches the rotary classifier 16 is classified into coarse pulverized fuel and fine pulverized fuel due to the relative balance between the centrifugal force generated by the rotation of the blades 16a and the centripetal force of the primary airflow. Specifically, the coarse pulverized fuel is knocked down by the blades 16a and returned to the pulverizing table 12 for re-pulverization. Meanwhile, the fine pulverized fuel enters the enclosed region 16X through the gaps between the blades 16a, swirls in the enclosed region 16X together with the primary air, and is guided to multiple outlet ports 19 provided in the ceiling portion 42 of the housing 11. The pulverized fuel (arrow A1) classified by the rotary classifier 16 is discharged from the enclosed area 16X through each outlet port 19 together with primary air (arrow A2) to each pulverized fuel supply line 120 and supplied to the burner 220 of the boiler 200.

[0032] The fuel supply device 20 of the fuel supply unit is connected to the bunker 21 via the downspout portion 24. The downspout portion 24 is a pipe that extends downward from the lower end portion of the bunker 21. A valve for switching the discharge state of the solid fuel from the bunker 21 may be provided midway along the downspout portion 24 . The fuel supply device 20 includes a conveying unit 22 and a coal feeder motor 23 . The conveying section 22 is, for example, a belt conveyor, and conveys the solid fuel discharged from the lower end of the downspout section 24 to the upper end of the fuel supply pipe 17 by the driving force of the coal feeder motor 23, and then feeds it into the inside of the fuel supply pipe 17. The amount of solid fuel supplied to the mill 10 (hereinafter also referred to as the "fuel supply amount") is controlled by a signal from the control unit 50, for example, by adjusting the movement speed of the belt conveyor of the transport unit 22.

[0033] When the solid fuel is biomass fuel (e.g., biomass pellets), the pellets stacked in the downspout section 24 are uniform in size and shape compared to coal, so the gap-filling effect (material sealing) of particles of different sizes and shapes is small, and the gaps formed between the pellets are large. As a result, the primary air inside the mill 10 may pass through gaps formed in the layer inside the downspout section 24 and flow back from inside the mill 10 through the downspout section 24 to the bunker 21, which may cause a decrease in the pressure inside the mill 10. If the pressure inside the mill 10 drops, various problems may occur in the stable operation of the solid fuel pulverizer 100 and boiler 200, such as a deterioration in the transportability of pulverized fuel inside the mill 10, the generation of dust inside the fuel supply device 20 and above the bunker 21, ignition of pellets inside the fuel supply device 20, bunker 21, or downspout section 24 due to the high temperature of the primary air, and a decrease in the amount of pulverized fuel transported to the burner 220. Therefore, a rotary valve 60 (see Figure 2) may be provided in the fuel supply pipe 17 connecting the fuel supply device 20 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 fuel supply device 20 and downspout section 24 to the bunker 21.

[0034] 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 . The blower section 30 includes, for example, 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 being blown.

[0035] The hot gas flow path 30a supplies part of the air sent out from the primary air ventilator 31 as hot gas that has been heated by passing through an air preheater 34 (heat exchanger). 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.

[0036] The cold gas flow path 30b supplies a part of the air sent out from the primary air ventilator 31 as cold gas at room temperature. The cold gas flow path 30b is provided with a cold gas damper 30d. 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.

[0037] 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. The temperature of the primary air is determined by the mixing ratio of the hot gas supplied from the hot gas passage 30a and the cold gas supplied from the cold gas passage 30b.

[0038] The boiler 200 includes a furnace 210 and a burner 220. The boiler 200 is a facility that generates combustion gas by burning pulverized fuel supplied from the solid fuel pulverizer 100, and generates steam by heat exchange between the generated combustion gas and water.

[0039] The burner 220 is a device that burns pulverized fuel to form a flame using a mixture of primary air and pulverized fuel supplied from the pulverized fuel supply line 120, and secondary air that is supplied by heating air (outside air) sent out from a forced draft fan (FDF) 32 using an air preheater 34. The pulverized fuel is combusted inside the furnace 210, and the high-temperature combustion gas passes through heat exchangers such as an evaporator, a superheater, and a coal economizer (not shown) before being discharged outside the boiler 200.

[0040] 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.Then, the combustion gas is guided via an induced draft fan (IDF) 33 to a chimney (not shown) 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.

[0041] The water supplied to each heat exchanger of the boiler 200 is heated in an economizer (not shown), and then further heated in an evaporator (not shown) and a superheater (not shown) to become high-temperature, high-pressure superheated steam. The superheated steam is sent to a steam turbine (not shown), which is one of the components that make up the power generation section, and drives the steam turbine to rotate. The steam turbine is connected to a generator (not shown), which is one of the devices that make up the power generation section, via a rotating shaft, and the rotation of the steam turbine drives the generator to generate electricity.

[0042] The solid fuel pulverizer 100 further includes a state detection unit 40 . The data measured or detected by the state detection unit 40 is sent to the control unit 50.

[0043] The state detection unit 40 is, for example, a differential pressure measurement means provided in the mill 10. The differential pressure measuring means is configured to measure the mill differential pressure. The mill differential pressure is the difference between the pressure at the carrier gas inlet 11a where primary air is introduced into the inside of the housing 11 from the carrier gas supply line 110 and the pressure at the outlet port 19 where the mixed gas (primary air and pulverized fuel) is discharged from the inside of the housing 11 to the pulverized fuel supply line 120. Increases and decreases in the mill differential pressure are affected by increases and decreases in the solid fuel and pulverized fuel remaining in the mill 10. By adjusting the rotation speed of the rotary classifier 16 in accordance with this mill differential pressure, it is possible to adjust the particle size and amount of pulverized fuel discharged from the outlet port 19 to the pulverized fuel supply line 120. This makes it possible to 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 burner 220.

[0044] The state detection unit 40 is, for example, a temperature measurement means provided in the mill 10. The temperature measuring means detects the temperature of the primary air at the carrier gas inlet 11a (hereinafter referred to as the "mill inlet primary air temperature") and the temperature of the mixed gas at the outlet port 19 (hereinafter referred to as the "mill outlet primary air temperature"), and controls the blower unit 30 so that the respective upper limit temperatures are not exceeded. Each upper limit temperature is determined taking into consideration the possibility of ignition depending on the properties of the solid fuel. Because the primary air is cooled by transporting the pulverized fuel while drying it inside the housing 11, the mill inlet primary air temperature is usually higher than the mill outlet primary air temperature. For example, the mill inlet primary air temperature is from room temperature to approximately 300°C, and the mill outlet primary air temperature is from room temperature to approximately 90°C.

[0045] The control unit 50 is a device that controls each part of the solid fuel pulverizer 100 . 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.

[0046] [Gas supply section] As shown in FIGS. 2 to 4, the solid fuel pulverizer 100 further includes a gas supply unit 80. The gas supply unit 80 is a device for supplying gas to the enclosed area 16X. Examples of the gas include primary air taken out from the blower 30 or the carrier gas supply line 110, and exhaust gas from the boiler 200. The properties of the supplied gas, such as temperature and humidity, are adjusted so as not to affect the pulverized fuel or the primary air. The gas supply unit 80 includes a header pipe 81, a plurality of branch pipes 82, a plurality of flow rate adjustment valves 83, and a plurality of nozzles 84 (ejection units).

[0047] The header pipe 81 is a pipe through which gas is guided from a supply source (for example, the blower 30, the carrier gas supply line 110, or the boiler 200). One ends of a plurality of branch pipes 82 are connected to the header pipe 81, and the header pipe 81 is configured to supply gas to each of the branch pipes 82.

[0048] The branch pipe 82 is a pipe through which gas is guided from the header pipe 81 . A nozzle 84 is connected to the other end of each branch pipe 82, and gas can be supplied from each branch pipe 82 to the nozzle 84. A flow rate adjustment valve 83 is connected to each branch pipe 82, and is configured to adjust the flow rate of the gas flowing through each branch pipe 82. The opening degree of the flow rate adjustment valve 83 is determined by the control unit 50. The gas supply unit 80 may be provided with a flow meter (not shown) that measures the flow rate of the gas flowing through each branch pipe 82, and the control unit 50 may arbitrarily adjust the amount of gas flowing through each branch pipe 82 by combining each flow rate adjustment valve 83 with each flow meter. The flow rate of the gas flowing through one branch pipe 82 corresponds to the flow rate of the gas sprayed from a nozzle 84 connected to that branch pipe 82.

[0049] The nozzle 84 is a part that ejects the gas introduced from the branch pipe 82 into the enclosed area 16X. The gas ejected from the nozzle 84 is indicated by an arrow A3 in FIGS. The tips of the nozzles 84 from which the gas is ejected are located at least within the enclosed region 16X. As shown in Fig. 4, the nozzles 84 are provided at equal angular intervals on an imaginary circle C2 centered on the central axis. The nozzles 84 are also arranged between the outlet ports 19 that are arranged at equal angular intervals in the circumferential direction around the central axis of the rotary classifier 16. By ejecting gas from any of the nozzles 84 or by changing the flow rate or the direction of ejection of gas from any of the nozzles 84, the flow of the mixed gas (primary air and pulverized fuel) swirling in the enclosed area 16X can be partially accelerated or decelerated. Therefore, for example, by flowing the mixed gas at a high flow rate toward the outlet port 19 (hereinafter referred to as the "specific outlet port 19") connected to the pulverized fuel supply line 120 to which a large amount of pulverized fuel is desired to be supplied, the flow rate of the mixed gas (i.e., the pulverized fuel) toward the specific outlet port 19 can be relatively increased. Note that the flow rate of the mixed gas toward the specific outlet port 19 may be relatively increased by slowing down the flow of the mixed gas toward the outlet ports 19 other than the specific outlet port 19. Furthermore, the flow of the mixed gas swirling in the enclosed region 16X can be stabilized by ejecting the gas from the nozzle 84 or by changing the flow rate or direction of the gas ejected from the nozzle 84. Therefore, for example, the flow rate of the mixed gas heading toward each outlet port 19 can be made uniform.

[0050] Each nozzle 84 is configured so that the direction in which the gas is ejected (hereinafter referred to as the "ejection direction") can be freely changed. For example, each nozzle 84 is configured so that its position can be changed as desired to change the spray direction. The position of each nozzle 84 may be changed by an actuator (not shown) or by an operator. Furthermore, the timing for changing the spray direction is not affected by the operating state of the mill 10 or the solid fuel pulverizer 100.

[0051] The ejection direction is preferably aligned with the flow direction of the mixed gas (pulverized fuel (arrow A1) and primary air (arrow A2)) swirling in the surrounding area 16X, thereby efficiently accelerating the flow of the mixed gas. The direction along the flow direction of the mixed gas is a direction having at least a velocity component that coincides with the mainstream direction of the mixed gas, and is, for example, a direction included in the range of approximately ±90 degrees (cross-hatching in Figure 5) with respect to the mainstream direction of the mixed gas, as shown in Figure 5.

[0052] 3, a pulverized fuel flow meter 121 is attached to each pulverized fuel supply line 120, and it is possible to grasp the amount (mass flow rate) of the pulverized fuel flowing through each pulverized fuel supply line 120. Note that the amount of the pulverized fuel flowing through each pulverized fuel supply line 120 may be estimated by measuring the pressure loss of each pulverized fuel supply line 120. The information obtained by each pulverized fuel flow meter 121 is transmitted to the control unit 50. The control unit 50, which has received the information, determines whether there is any variation in the amount of pulverized fuel flowing through each pulverized fuel supply line 120 (for example, variation exceeding a predetermined range that can be tolerated in design), that is, whether the amount of pulverized fuel flowing through each pulverized fuel supply line 120 is approximately uniform. If the amount of pulverized fuel is not substantially uniform, the control unit 50 controls the actuators that change the attitude of each nozzle 84 to change the direction of gas ejection, or issues a warning to prompt the operator to change the attitude of each nozzle 84. If the amount of pulverized fuel is not substantially uniform, the control unit 50 adjusts the flow rate of gas ejected from each nozzle 84 by controlling the opening of each flow rate control valve 83, or issues a warning to prompt the operator to change the opening of each flow rate control valve 83. Note that in order to eliminate the non-uniformity in the amount of pulverized fuel, at least one of changing the ejection direction and adjusting the gas flow rate may be performed.

[0053] [Variation 1] In the above description, the flow rate of the gas mixture toward the specific outlet port 19 is relatively increased to supply a larger amount of pulverized fuel to the pulverized fuel supply line 120 connected to the specific outlet port 19 . However, this method is merely one example for supplying more pulverized fuel to the pulverized fuel supply line 120 connected to a specific outlet port 19, and the specific gas supply method is not limited to this as long as it can supply more pulverized fuel to the pulverized fuel supply line 120.

[0054] The solid fuel pulverizer, the boiler facility, and the method of operating the solid fuel pulverizer according to the present embodiment described above can be understood as follows.

[0055] A solid fuel pulverizer (100) according to a first aspect of the present disclosure includes a housing (11), a rotary table (12) provided inside the housing (11) and rotating around a central axis extending in a vertical direction, a pulverizer roller (13) provided inside the housing (11) for pulverizing solid fuel by pinching it between the rotary table (12) and the roller (13) to produce pulverized fuel, a carrier gas supply line (110) for supplying a carrier gas for transporting the pulverized fuel into the housing (11), and a rotary table (12) provided inside the housing (11) and rotating around a central axis extending in a vertical direction. The apparatus includes a rotary classifier (16) having a plurality of blades (16a) arranged in a circumferential direction around a line, which classifies pulverized fuel introduced together with a carrier gas, a plurality of ejection sections (84) which eject gas into an enclosed area (16X) surrounded by the plurality of blades (16a) arranged in a circumferential direction, and a plurality of pulverized fuel supply lines (120) which supply the pulverized fuel having a particle size of a predetermined particle size or less classified by the rotary classifier (16) together with the carrier gas from the enclosed area (16X) to a boiler (200) via a plurality of outlet ports (19) of the housing (11).

[0056] The system includes a plurality of ejection sections (84) that eject gas into an enclosed region (16X) surrounded by a plurality of circumferentially arranged blades (16a), and a plurality of pulverized fuel supply lines (120) that supply pulverized fuel having a particle size equal to or smaller than a predetermined particle size together with carrier gas from the enclosed region (16X) to the boiler (200) via a plurality of outlet ports (19). This allows the gas ejected from the ejection sections (84) to partially accelerate or decelerate the flow of the mixed gas (carrier gas and pulverized fuel) swirling in the enclosed region (16X). For example, by flowing the mixed gas at a high velocity toward an outlet port (19) connected to a pulverized fuel supply line (120) to which a large amount of pulverized fuel is desired, the flow rate of the mixed gas (i.e., the pulverized fuel) toward the outlet port (19) can be relatively increased. By adjusting each outlet port (19) in this manner while considering the overall balance, the amount of pulverized fuel supplied to each pulverized fuel supply line (120) can be made uniform.

[0057] In the solid fuel pulverization device (100) according to the second aspect of the present disclosure, in the first aspect, each of the ejection parts (84) ejects gas in a direction along the flow direction of the carrier gas swirling in the enclosed area (16X).

[0058] Each of the ejection portions (84) ejects gas in a direction parallel to the flow direction of the carrier gas swirling in the enclosed region (16X), thereby efficiently accelerating the flow of the mixed gas.

[0059] In the solid fuel pulverization device (100) according to the third aspect of the present disclosure, in the first or second aspect, the outlet ports (19) are arranged in a line in the circumferential direction, and each of the ejection portions (84) is arranged in a line in the circumferential direction and is disposed between adjacent outlet ports (19) in the circumferential direction.

[0060] The ejection portions (84) are arranged side by side in the circumferential direction and are disposed between adjacent outlet ports (19) in the circumferential direction, so that gas can be efficiently ejected toward each outlet port (19).

[0061] In the solid fuel pulverizer (100) according to a fourth aspect of the present disclosure, in any one of the first to third aspects, the gas ejected from each of the ejection parts (84) is a carrier gas.

[0062] The gas ejected from each ejection portion (84) is used as a carrier gas and therefore does not affect combustion in the boiler (200).

[0063] A boiler facility according to a fifth aspect of the present disclosure includes the solid fuel pulverizer (100) according to any one of the first to fourth aspects, and a boiler (200) that burns pulverized fuel in a combustion device to generate steam.

[0064] A boiler facility including a boiler (200) capable of realizing stable combustion by supplying a uniform amount of pulverized fuel through each pulverized fuel supply line (120) can be provided.

[0065] An operating method of a solid fuel pulverization apparatus (100) according to a sixth aspect of the present disclosure is a method of operating the solid fuel pulverization apparatus (100) according to any one of the first to fourth aspects, in which at least one of the direction of the gas ejected from each of the ejection portions (84) and the flow rate of the gas ejected from each of the ejection portions (84) is adjusted.

[0066] At least one of the direction of the gas ejected from each ejection portion (84) and the flow rate of the gas ejected from each ejection portion (84) is adjusted, so that the direction and speed of the mixed gas flowing toward the outlet port (19) can be easily adjusted.

[0067] In the operating method of the solid fuel pulverizer (100) according to the seventh aspect of the present disclosure, in the sixth aspect, the amount of pulverized fuel flowing through each of the pulverized fuel supply lines (120) is grasped, and at least one of the direction of the gas ejected from each of the ejection portions (84) and the flow rate of the gas ejected from each of the ejection portions (84) is adjusted based on the flow rate of the pulverized fuel flowing through each of the pulverized fuel supply lines (120).

[0068] The amount of pulverized fuel flowing through each pulverized fuel supply line (120) is grasped, and at least one of the direction of the gas ejected from each ejection section (84) and the flow rate of the gas ejected from each ejection section (84) is adjusted based on the flow rate of the pulverized fuel flowing through each pulverized fuel supply line (120). Therefore, the direction and speed of the mixed gas toward each outlet port (19) can be adjusted according to the amount of pulverized fuel flowing through each pulverized fuel supply line (120), and the amount of pulverized fuel flowing through each pulverized fuel supply line (120) can be easily made uniform. [Explanation of symbols]

[0069] 1. Power Plant 10 mils 11. Housing 11a Carrier gas inlet (inlet) 12 Grinding table (rotary table) 13 Crushing roller 14 Reducer 15 Mill motor (drive unit) 16 Rotary classifier (rotary classifier section) 16a blade 17 Fuel supply pipe 18 Classifier motor 19 Exit Port 20 Fuel supply device 21 Banka 22 Conveyor 23 Coal feeder motor 24 Downspout 30 Blower 30a Hot gas flow path 30b Cold gas flow path 30c Thermal Gas Damper 30d Cold Gas Damper 31 Primary air ventilator 34 Air preheater 40 Status detection unit 41 Bottom part 42 Ceiling 45 Journal Head 47 Support Arm 48 Support shaft 49 Pressing device 50 control section 60 Rotary Valve 70 Biting part 72 Fuel layer 80 Gas supply section 81 Header pipe 82 Branch Pipe 83 Flow control valve 84 Nozzle (jet part) 100 Solid fuel crusher 110 Carrier gas supply line 120 Pulverized fuel supply line 121 Fine fuel flow meter 200 boiler 210 Furnace 220 Burner (combustion device) A1 Pulverized fuel flow A2 Primary air flow L1 Rotation axis (central axis)

Claims

1. Housing and a rotary table provided inside the housing and rotating about a central axis extending in a vertical direction; a crushing roller provided inside the housing, which crushes the solid fuel between the rotating table and the crushing roller to produce crushed fuel; a carrier gas supply line for supplying a carrier gas for transporting pulverized fuel into the interior of the housing; a rotary classifier unit provided inside the housing, the rotary classifier unit having a plurality of blades extending in the vertical direction and arranged side by side in a circumferential direction around the central axis, the rotary classifier unit classifying the pulverized fuel introduced together with the carrier gas; a plurality of ejection portions that eject gas into an enclosed area surrounded by the plurality of blades that are arranged side by side in the circumferential direction; a plurality of pulverized fuel supply lines for supplying pulverized fuel classified by the rotary classifier to a boiler with a carrier gas through a plurality of outlet ports of the housing from the enclosed area; Equipped with Solid fuel crushing equipment.

2. Each of the ejection portions ejects gas in a direction along the flow direction of the carrier gas swirling in the surrounding area.

2. The solid fuel pulverizer of claim 1.

3. The outlet ports are arranged side by side in the circumferential direction, The jet portions are arranged side by side in the circumferential direction and are arranged between the outlet ports adjacent to each other in the circumferential direction.

2. The solid fuel pulverizer of claim 1.

4. The gas ejected from each of the ejection portions is a carrier gas.

2. The solid fuel pulverizer of claim 1.

5. The solid fuel pulverizer according to claim 1; the boiler by burning pulverized fuel in a combustion device to generate steam; Equipped with Boiler equipment.

6. 2. A method for operating a solid fuel pulverizer according to claim 1, comprising: At least one of the direction of the gas ejected from each of the ejection parts and the flow rate of the gas ejected from each of the ejection parts is adjusted. Method for operating a solid fuel pulverizer.

7. determining the amount of pulverized fuel flowing through each of said pulverized fuel supply lines; At least one of the direction of the gas ejected from each of the ejection portions and the flow rate of the gas ejected from each of the ejection portions is adjusted based on the flow rate of the pulverized fuel flowing through each of the pulverized fuel supply lines.

7. A method for operating a solid fuel pulverizer according to claim 6.

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