JP2020085338A - Solid fuel supply device and method, crusher, and boiler - Google Patents

Abstract

To suppress operation stop of a rotary valve to secure stable supply for solid fuel, in a solid fuel supply device and method and a boiler.SOLUTION: A solid fuel supply device comprises: a solid fuel supply pipe 63 that supplies solid fuel; a rotary valve 64 provided on the solid fuel supply pipe 63 and having a rotatable impeller 82; a detector 115 that detects biting in the rotary valve 64; and a controller 65 that when the detector 115 detects the biting, rotates the impeller 82 in a reverse direction for a predetermined time Tb set in advance and then rotates it in a normal direction.SELECTED DRAWING: Figure 3

Description

The present invention relates to a solid fuel supply device and method, a crusher equipped with this solid fuel supply device, and a boiler equipped with this crusher.

The boiler has a furnace that has a hollow shape and is installed in the vertical direction, and a plurality of combustion devices (combustion burners) are arranged along the circumferential direction on the furnace wall. In the boiler, a flue is connected vertically above the furnace, and a heat exchanger for generating steam is arranged in the flue. Then, the combustion burner injects a mixture of fuel and air into the furnace to form a flame, and high-temperature combustion gas is generated and flows into the flue. The combustion gas flowing to the flue heats water and steam flowing in the plurality of heat transfer tubes forming the heat exchanger to generate superheated steam.

In the boiler, the solid fuel pulverized by the solid fuel supply device is supplied to the combustion burner. The solid fuel supply device includes a bunker, a fuel supply device, a solid fuel supply pipe, a pulverizer (mill), and a fine powder fuel supply pipe. The fuel supplier supplies the bunker solid fuel to the crusher through the solid fuel supply pipe. The pulverizer pulverizes the solid fuel into a fine powder having a particle size smaller than a predetermined particle size, and supplies the fine fuel to the combustion burner through a fine fuel supply pipe.

In recent years, the utilization of renewable energy has been promoted, and the application of biomass as a solid fuel is required. As a carbon-containing solid fuel, a wood-based biomass fuel is difficult to be finely pulverized, has high combustibility, and has a property that can be suitably burned even with a relatively large particle size. Therefore, when a biomass fuel is used as a solid fuel, it is usually supplied from a pulverizer to a combustion device (combustion burner) provided in a boiler in a state of a particle size about 5 to 10 times larger than that of coal. Is.

As described above, since the particle size supplied to the combustion burner is different between coal and biomass fuel, the crusher for crushing and classifying the solid fuel has different designs for biomass fuel crushing application and coal crushing application (for example, housing shape). , The rotation speed of the rotary table, the rotation speed of the classifier, etc.), and it is originally preferable to individually design. However, from the viewpoint of equipment cost, installation space, etc., the same crusher can handle both solid fuels of biomass fuel and coal, and a crusher that can share both coal and biomass fuel It is desired to be able to use and use biomass fuels.

Biomass fuel is chips or pellets obtained by compression-molding wood chips into a predetermined size, and has a constant particle size. Therefore, when the biomass fuel is stored in the down spout part between the bunker and the fuel supplier, the gap between the biomass fuels is larger in the biomass fuel than in the case of the coal fuel. When pulverizing biomass fuel, the pulverizer is supplied with high-temperature air for drying and carrying. Then, high temperature air blown up from the inside of the crusher may pass through this gap and blow out to the bunker, which may deteriorate the transportability of the biomass fuel, generate dust, and ignite the down spout portion. Therefore, a rotary valve is provided between the coal feeder and the fuel supply pipe to secure the sealing property and suppress the backflow due to the blowing of the high temperature gas from the crusher to the bunker. An example of a fuel supply unit provided with a rotary valve is described in Patent Document 1 below.

Japanese Patent No. 4716217

The rotary valve has a structure in which an impeller is rotatably supported in a casing. The biomass fuel enters the space between the plurality of blades in the impeller and is conveyed by the rotation of the impeller. At this time, in the impeller, the sealing performance is secured by setting the gaps between the tips of the plurality of blades and the inner surface of the casing to be narrow. However, the biomass fuel is obtained by compression-molding a pulverized product of a tree, etc., and there is a possibility that fibers such as tree bark and foreign matter such as wood chips are mixed during the production of the biomass fuel. Therefore, when the impeller rotates, the fibrous substance or foreign matter may enter the gap between the tip of the blade and the inner surface of the casing. Then, if the material that entered the gap between the tips of the blades and the inner surface of the casing is made of wood fiber, friction increases and biting occurs, and if the foreign matter that enters the gap is hard, it is caught. There is a risk that biting will occur, impede the rotation of the impeller, and stop the operation of the rotary valve. If the operation of the rotary valve stops at all, the biomass fuel cannot be supplied to the crusher, and the crusher cannot generate the pulverized fuel and continuously convey it to the combustion burner, which leads to stable operation of the boiler. May cause trouble.

The present invention is to solve the above-mentioned problems, and an object of the present invention is to provide a solid fuel supply device and method, a crusher, and a boiler that suppress the total operation stop of the rotary valve to secure the supply of solid fuel. ..

A solid fuel supply device of the present invention for achieving the above object is a solid fuel supply pipe for supplying a solid fuel, a rotary valve provided on the solid fuel supply pipe and having a rotatable impeller, and the rotary valve. A detector for detecting bite in the valve, and a controller for rotating the impeller in the reverse direction for a predetermined time set in advance when the detector detects the bite and then rotating in the forward direction. It is characterized by that.

Therefore, when the impeller of the rotary valve rotates in the forward direction to supply the solid fuel through the solid fuel supply pipe, when the detector detects the biting in the rotary valve, the control device keeps the impeller for a predetermined time. Rotate in the opposite direction and then rotate in the forward direction. That is, when the impeller rotates in the forward direction, if fibrous or foreign matter is caught in the gap between the radial tip of the impeller and the inner surface (sealing surface) of the casing, the impeller is moved in the reverse direction. By rotating, the bite in the impeller is eliminated, and the fibrous substance or the foreign material in which the bite is generated is accommodated in the transport space provided between the plurality of blades. Then, when the impeller is rotated in the forward direction after the elapse of a predetermined time, the fibrous material or the foreign matter contained in the conveying space of the impeller does not re-engage, and the solid fuel and the solid fuel supply pipe properly feed the crusher. Supplied. As a result, it is possible to secure the supply of solid fuel by suppressing all the operation stop of the rotary valve.

In the solid fuel supply device of the present invention, the solid fuel supply pipe is provided with a pulverizer on the downstream side in the supply direction of the solid fuel, and the pulverization process of the solid fuel by the pulverizer is completed for the predetermined time. It is characterized by being set to a time shorter than the time.

Therefore, the predetermined time is set to a time shorter than the time when the crushing process of the solid fuel by the crusher is completed. The pulverized fuel produced by pulverizing the solid fuel held in the pulverizer can be continuously supplied. After that, since the impeller is rotated in the forward direction after the lapse of a predetermined time, the trapping is eliminated before the pulverization processing of the solid fuel held by the pulverizer is completed and the supply of the pulverized fuel is completed. The solid fuel supply to the crusher can be restarted, and the fine fuel can be continuously supplied.

In the solid fuel supply device of the present invention, the predetermined time is set to a time between 1/4 rotation and 1/2 rotation of the impeller.

Therefore, while the impeller is rotated in the opposite direction from 1/4 rotation to 1/2 rotation, the bite generation part of the impeller may be located vertically above the horizontal position, and the fibrous material or foreign matter that has bite Are gravitationally dropped and housed in the transfer space provided between the plurality of blades. For this reason, since the predetermined time is set to a time between 1/4 rotation and 1/2 rotation of the impeller, the rotation in the opposite direction is not performed for a long time, so that the solid fuel adheres to the inner surface of the seal surface of the casing. It is possible to promptly eliminate the bite and restart the supply of the solid fuel to the crusher while preventing the occurrence of the crushing.

In the solid fuel supply device of the present invention, when the impeller rotates in the forward direction, the amount of the solid fuel contained in the transfer space provided between the plurality of blades is smaller than the volume of the transfer space. It is characterized by being set.

Therefore, the amount of solid fuel contained in the transfer space of the impeller can be adjusted by, for example, the amount of solid fuel supplied from the solid fuel supply pipe and the rotational speed of the impeller. Since the amount of solid fuel stored in the transfer space of the impeller is set to be smaller than the volume of the transfer space, when the rotary valve is bitten and the impeller is rotated in the opposite direction. If the fibrous material or foreign matter caught in the impeller falls off, the dropped fibrous material or foreign matter can be stored in the transport space, and when the impeller is rotated in the forward direction after a predetermined time has elapsed, Alternatively, it is possible to restart the supply of the solid fuel without the foreign matter being re-engaged with the impeller.

The solid fuel supply device of the present invention is characterized in that the amount of the solid fuel contained in the transfer space is set to 30% to 80% of the volume of the transfer space.

Therefore, since the amount of solid fuel accommodated in the transfer space portion is set to 30% to 80% of the volume of the transfer space portion, an appropriate amount of solid fuel can be efficiently supplied, and at the same time from the impeller. It is possible to properly store the fallen bitten fiber or foreign matter in the transport space.

In the solid fuel supply device of the present invention, it has an electric motor for driving and rotating the impeller, the detector detects a current value or a power value of the electric motor, and the control device controls the electric current of the electric motor. When the value or the power value reaches a preset determination value, the impeller is rotated in the opposite direction for the predetermined time.

Therefore, when the current value or the electric power value of the electric motor reaches the determination value, the detector detects the bite and rotates the impeller in the opposite direction. Since the detection of the bite of this detector is easy and reliable, the fiber valve or the foreign substance is caught in the rotary valve based on the detection result of the current or electric power detector of the existing electric motor. It is possible to detect and suppress an increase in cost related to the detector.

In the solid fuel supply device of the present invention, the control device stops the rotation of the impeller when the number of times of rotating the impeller in the reverse direction exceeds a preset predetermined number of reverse rotations.

Therefore, when the number of rotations of the impeller in the reverse direction exceeds the predetermined number of reverse rotations, the rotation of the impeller is stopped, so that the operation of the rotary valve can be performed when the entrainment of fibrous material or foreign matter in the rotary valve cannot be eliminated. By stopping, the occurrence of damage or failure of the rotary valve can be suppressed in advance.

In the solid fuel supply device of the present invention, when the control device rotates the impeller in the opposite direction for the predetermined time and the detector detects a bite during the predetermined time, the control device rotates the impeller. It is characterized by stopping.

Therefore, even if the impeller is rotated in the opposite direction for a predetermined period of time, if the detector detects the entrapment and the entrapment of fibrous material or foreign matter is not eliminated, it is possible that the rotary valve itself other than the entrapment is abnormal. Therefore, by stopping the operation of the rotary valve at this time, it is possible to prevent damage or failure of the rotary valve in advance.

The solid fuel supply device of the present invention is characterized in that the casing that rotatably supports the impeller is provided with an inspection port.

Therefore, since the inspection port is provided in the casing of the impeller, when the entrainment of fibrous material or foreign matter is not resolved even if the impeller is rotated in the opposite direction, the operator should check the inspection after stopping the operation of the rotary valve. It is possible to reliably remove the fibrous substance or foreign matter that has been bitten into the impeller through the mouth, and to promptly restart the operation of the rotary valve.

The solid fuel supply device of the present invention is characterized in that a decomposable connecting portion is provided in the solid fuel supply pipe upstream of the rotary valve in the supply direction of the solid fuel.

Therefore, since the disassembled connecting portion is provided on the upstream side of the rotary valve in the solid fuel supply pipe, the operation of the rotary valve can be performed when the entrainment of fibrous material or foreign matter is not eliminated even if the impeller is rotated in the opposite direction. After stopping, the operator can disassemble the connecting portion and open the inlet portion of the rotary valve to remove even large fibrous substances or foreign matter caught in the impeller.

The solid fuel supply device of the present invention is characterized in that a trapping simulation switch for outputting a trapping signal from the control device regardless of the detection result of the detector is provided.

Therefore, the operator can rotate the impeller in the reverse direction for a predetermined time and then in the positive direction by the bite simulation switch regardless of the detection result of the detector, and the detector does not detect the bite. Even in the state, slight entrapment of fibrous material or foreign matter is eliminated. In addition, by performing a trial run of the impeller in advance, it is possible to find out a malfunction or the like in advance.

In the solid fuel supply device of the present invention, a forward rotation switch of the rotary valve, a reverse rotation switch of the rotary valve, and a display panel of the detector are arranged in the vicinity of the rotary valve. ..

Therefore, since the forward rotation switch, the backward rotation switch, and the display board are arranged in the vicinity of the rotary valve, the operator can easily operate the forward rotation switch and the backward rotation switch while looking at the display board. it can.

Further, in the solid fuel supply method of the present invention, in a solid fuel supply device in which a solid fuel supply pipe for supplying solid fuel is provided with a rotary valve having a rotatable impeller, the impeller is rotated to supply the solid fuel. A step of supplying the solid fuel by a pipe; a step of rotating the impeller in a reverse direction for a predetermined time set in advance when detecting the bite in the rotary valve; and a step of rotating the impeller after the elapse of the predetermined time. And a step of rotating in a positive direction.

Therefore, when the impeller rotates in the forward direction, if a fibrous substance or a foreign substance is caught in the gap between the radial tip of the impeller and the inner surface (sealing surface) of the casing, the bite is detected, and the impeller is detected. Is rotated in the opposite direction, the engagement of the fibrous material or the foreign material in the impeller is eliminated, and the fibrous material or the foreign material is accommodated in the transport space provided between the plurality of blades. Then, when the impeller is rotated in the forward direction after the elapse of a predetermined time, the fibrous material or the foreign matter contained in the conveying space of the impeller is properly bitten by the solid fuel supply pipe together with the solid fuel without being re-engaged. .. As a result, it is possible to secure the supply of solid fuel by suppressing all the operation stop of the rotary valve.

A crusher of the present invention is characterized by including the solid fuel supply device.

Therefore, the solid fuel can be continuously supplied to the boiler.

Further, the boiler of the present invention is characterized by including a solid fuel supply device.

Therefore, the solid fuel supply device can continuously supply the solid fuel to the boiler, and the stable operation of the boiler can be continued.

According to the solid fuel supply device and method, the crusher and the boiler of the present invention, it is possible to secure the supply of the solid fuel by suppressing all the operation stop of the rotary valve.

FIG. 1 is a schematic configuration diagram showing the boiler of the first embodiment. FIG. 2 is a schematic configuration diagram showing the solid fuel supply device of the first embodiment. FIG. 3 is a schematic diagram showing a rotary valve in the solid fuel supply device. FIG. 4 is a plan view showing the arrangement of the rotary valve. FIG. 5 is a flowchart showing the operation of the solid fuel supply device. FIG. 6 is a schematic diagram showing a state in which foreign matter is caught in the rotary valve. FIG. 7 is a schematic diagram showing a reverse rotation state of the rotary valve. FIG. 8 is a schematic diagram showing a forward rotation state of the rotary valve. FIG. 9 is a flowchart showing the operation of the solid fuel supply system of the second embodiment. FIG. 10 is a time chart showing the operation of the solid fuel supply device.

Hereinafter, preferred embodiments of a solid fuel supply device and method and a boiler according to the present invention will be described in detail with reference to the accompanying drawings. It should be noted that the present invention is not limited to this embodiment, and when there are a plurality of embodiments, the present invention also includes those configured by combining the respective embodiments.

[First Embodiment]
FIG. 1 is a schematic configuration diagram showing the boiler of the first embodiment.

The boiler of the first embodiment uses, for example, a pulverized fuel (solid carbon-containing fuel) obtained by pulverizing biomass, burns the pulverized fuel with a combustion burner, and recovers the heat generated by this combustion to supply water or steam and heat. It is a pulverized fuel fired boiler that can be exchanged to generate superheated steam. In the following description, the upper, upper, and upper parts mean the upper side in the vertical direction, and the lower, lower, and lower parts mean the lower side in the vertical direction.

In the first embodiment, as shown in FIG. 1, the boiler 10 has a furnace 11, a combustion device 12, and a flue 13. The furnace 11 has a hollow rectangular tube shape and is installed along the vertical direction. The furnace wall (heat transfer tube) that constitutes the furnace 11 is composed of a plurality of evaporation tubes and fins that connect them, and suppresses the temperature rise of the furnace wall by exchanging heat with water supply or steam.

The combustion device 12 is provided on the lower side of the furnace wall forming the furnace 11. In the present embodiment, the combustion device 12 has a plurality of combustion burners (for example, 21, 22, 23, 24, 25) mounted on the furnace wall. For example, the combustion burners 21, 22, 23, 24, 25 are arranged in a plurality of stages along the vertical direction, with one set of combustion burners arranged at equal intervals along the circumferential direction. However, the shape of the furnace, the number of combustion burners in one stage, and the number of stages are not limited to this embodiment.

Each combustion burner 21, 22, 23, 24, 25 is connected to a pulverizer (mill) 31, 32, 33, 34, 35 via a fine powder fuel supply pipe 26, 27, 28, 29, 30. Although not shown, the crushers 31, 32, 33, 34, and 35 have, for example, a rotary table rotatably supported in a housing, and a plurality of rollers interlocked with the rotation of the rotary table above the rotary table. And is rotatably supported. When the solid fuel is introduced between the plurality of rollers and the rotary table, the pulverized fuel is pulverized into a predetermined size of the pulverized fuel, and the pulverized fuel classified by the carrier gas (primary air) is fed into the pulverized fuel supply pipe 26. , 27, 28, 29, 30 to the combustion burners 21, 22, 23, 24, 25.

Further, in the furnace 11, a wind box 36 is provided at a mounting position of each combustion burner 21, 22, 23, 24, 25, and one end portion of an air duct 37 is connected to the wind box 36. The air duct 37 is provided with a blower 38 at the other end.

Further, the furnace 11 is provided with an additional air nozzle 39 above the mounting position of each combustion burner 21, 22, 23, 24, 25. An end of a branched air duct 40 branched from the air duct 37 is connected to the additional air nozzle 39. Therefore, the combustion air (fuel gas combustion air/secondary air) sent by the blower 38 is supplied from the air duct 37 to the wind box 36, and the combustion burners 21, 22, 23, 24, and 25, and additional combustion air (additional air) sent by the blower 38 can be supplied from the branch air duct 40 to the additional air nozzle 39.

The flue 13 is connected to a vertically upper portion of the furnace 11. The flue 13 is provided with superheaters 41, 42, 43, reheaters 44, 45, and economizers 46, 47 as heat exchangers for recovering the heat of the combustion gas. Heat is exchanged between the combustion gas generated by combustion and the feed water or steam flowing through each heat exchanger.

The flue 13 is connected to a gas duct 48 on the downstream side from which the combustion gas having undergone heat exchange is discharged. An air heater (air preheater) 49 is provided between the gas duct 48 and the air duct 37, and heat is exchanged between the air flowing through the air duct 37 and the combustion gas flowing through the gas duct 48. , 23, 24, 25 can be heated.

Further, the flue 13 is provided with a denitration catalyst 50 at a position upstream of the air heater 49. The denitration catalyst 50 supplies a reducing agent having a function of reducing nitrogen oxides such as ammonia and urea water into the flue 13, and causes the combustion gas supplied with the reducing agent to react with the nitrogen oxides and the reducing agent. By promoting it, nitrogen oxides in the combustion gas are removed and reduced. The gas duct 48 connected to the flue 13 is provided with a dust treatment device (electrostatic precipitator, desulfurization device) 51, an induced air blower 52, etc. at a position downstream of the air heater 49, and a chimney 53 at the downstream end. ing.

On the other hand, when the crushers 31, 32, 33, 34, 35 are driven, the generated fine powder fuel passes through the fine powder fuel supply pipes 26, 27, 28, 29, 30 together with the carrier air, and the combustion burners 21, 22, 23, 24. , 25. Further, the heated combustion air is supplied from the air duct 37 to the respective combustion burners 21, 22, 23, 24, 25 via the wind box 36. Then, the combustion burners 21, 22, 23, 24, 25 blow a fine powder fuel mixture in which fine powder fuel and a carrier gas (primary air) are mixed into the furnace 11, and at the same time, blow combustion air into the furnace 11. A flame can be formed by igniting. A flame is generated in the lower part of the furnace 11, and the combustion gas rises in the furnace 11 and is discharged to the flue 13.

In the lower region A of the furnace 11, the pulverized fuel mixture and the combustion air (secondary air) burn to generate a flame. Here, the furnace 11 is set so that the supply amount of air is less than the theoretical air amount with respect to the supply amount of the pulverized fuel, so that the inside is maintained in the reducing atmosphere. That is, in the region B, NOx generated by combustion of the fine powder fuel is reduced in the furnace 11, and then additional air is additionally supplied from the additional air nozzle 39 to complete the oxidative combustion of the fine powder fuel, and The amount of NOx generated by combustion is reduced.

After that, the combustion gas is heat-exchanged by the superheaters 41, 42, 43, the reheaters 44, 45, and the economizers 46, 47 arranged in the flue 13, and then the nitrogen oxides are reduced and removed by the denitration catalyst 50. Then, the particulate matter is removed by the soot and dust treatment device 51 and the sulfur content is removed, and then the dust is discharged from the chimney 53 into the atmosphere.

FIG. 2 is a schematic configuration diagram showing the solid fuel supply device of the first embodiment.

In the first embodiment, as shown in FIG. 2, the solid fuel supply device 60 supplies a solid fuel such as biomass to the grinder 31 (32, 33, 34, 35). The crusher 31 crushes the supplied solid fuel to generate pulverized fuel and supplies it to the combustion device 12 of the boiler 1. The pulverizer 31 for pulverizing solid fuel such as coal or biomass fuel supplied to the boiler 1 into pulverized solid fuel, which is pulverized solid fuel, may be of a type that pulverizes only coal or only biomass fuel. May be used, or the biomass fuel may be crushed together with coal.

The solid fuel supply device 60 includes a bunker 61, a fuel supply device 62, a solid fuel supply pipe 63, a rotary valve 64, a crusher 31, a fine powder fuel supply pipe 26 (27, 28, 29, 30), And a control device 65.

The bunker 61 stores the biomass fuel as a solid fuel in this embodiment. The bunker 61 includes a down spout portion 71 immediately below. Here, the biomass fuel is a renewable organic resource derived from a living organism, and includes, for example, thinned wood, waste wood, driftwood, grass, waste, sludge, tires, and recycled fuel (pellets and Chip) and the like, and is not limited to those presented here. Biomass fuel is carbon-neutral that does not emit carbon dioxide, which is a global warming gas, because it captures carbon dioxide during the growth process of biomass, and therefore various uses thereof have been studied.

The fuel supplied to the boiler 10 is not limited to the biomass fuel, and may be coal or a mixed fuel of coal and biomass.

The fuel supplier 62 includes a transport unit 72 and an electric motor 73. The transport unit 72 transports the solid fuel discharged from the lower end portion of the down spout portion 71 immediately below the bunker 61 by the driving force provided by the electric motor 73, and supplies the solid fuel to the solid fuel supply pipe 63. The supply amount of the solid fuel supplied to the solid fuel supply pipe 63 is adjusted by the belt speed of the belt conveyor that constitutes the transport unit 72.

The solid fuel supply pipe 63 is arranged between the fuel supply device 62 and the crusher 31. The solid fuel supply pipe 63 is composed of an upper fuel supply pipe 74 and a lower fuel supply pipe 75. The upper end of the upper fuel supply pipe 74 is connected to the fuel supplier 62, and the lower end of the lower fuel supply pipe 75 is connected to the crusher 31. A rotary valve 64 is provided between the upper fuel supply pipe 74 and the lower fuel supply pipe 75. The rotary valve 64 is connected to a lower end portion of the upper fuel supply pipe 74 via an upper connecting portion (connecting portion) 76, and is connected to an upper end portion of the lower fuel supply pipe 75 via a lower connecting portion 77. A sleeve joint is applied to the upper fuel supply pipe 74 as the disassembleable upper connecting portion 76. The sleeve joint covers, for example, a connection portion between the upper fuel supply pipe 74 and an upper side of an upper pipe (not shown) that is connected to the supply port 92 of the rotary valve 64 with a tubular portion, and the tubular portion is tightened with a tightening band (tightening band) from the outer peripheral side. It is fixed by tightening it with a fixing tool). To disassemble the upper connecting portion 76, the tightening band that fastens the sleeve joint tube portion may be loosened or removed, and then the sleeve joint tube portion may be slid upward or downward. The rotary valve 64 includes a casing 81, an impeller 82, and an electric motor 83.

The biomass fuel chips and pellets before crushing have a constant particle size (the pellet size is, for example, about 6 to 8 mm in diameter and about 40 mm or less in length) and lighter than the coal fuel. .. Therefore, when the biomass fuel is stored in the down spout portion 71, the gap formed between the biomass fuels is larger than that of the coal fuel. Then, since there is a gap between the biomass fuel chips and pellets in the down spout portion 71, the primary air blown up from the inside of the pulverizer 31 and the fine powder fuel pass through the gap formed between the biomass fuels. The pressure inside the crusher 31 may decrease. Further, when the primary air blows through the storage part of the bunker 61, if the transportability of the biomass fuel is deteriorated, dust is generated, the down spout 71 is ignited, and the pressure inside the crusher 31 is reduced, the transfer of the fine powder fuel is performed. Various problems may occur in the operation of the crusher 31, such as a decrease in the amount. For this reason, a rotary valve 64 is provided in the solid fuel supply pipe 63 to suppress the backflow caused by the blowing up of the primary air and the fine powder fuel.

Although not shown, the crusher 31 includes a rotary table, rollers, and a classifying unit inside the housing. When the solid fuel supplied from the solid fuel supply pipe 63 is fed to the center of the rotary table, the solid fuel is guided to the outer peripheral side of the rotary table by the centrifugal force generated by the rotation of the rotary table and is sandwiched between the rollers. Be crushed. The crushed solid fuel becomes crushed solid fuel and is wound up by the primary air as a carrier gas. The crushed solid fuel that has reached the classifying section is crushed by the classifying blade to spin off the coarse powdered fuel with a large diameter due to the relative balance between the centrifugal force generated by the rotation of the classifying blade and the centripetal force generated by the primary air flow. The powder is returned to the table and pulverized again, and the fine powder fuel is guided from the housing to the fine powder fuel supply pipe 26 and flows out. The pulverized fuel flowing out to the pulverized fuel supply pipe 26 is supplied to the combustion device 12 of the boiler 10.

The control device 65 controls the operations of the fuel supply device 62, the rotary valve 64, and the crusher 31. That is, the control device 65 adjusts the amount of solid fuel supplied to the upper fuel supply pipe 74 by controlling the operation speed of the transport unit 72 by the electric motor 73 of the fuel supply machine 62. The control device 65 controls the rotation speed of the impeller 82 by the electric motor 83 of the rotary valve 64 to adjust the amount of solid fuel supplied to the lower fuel supply pipe 75. The control device 65 can adjust the supply amount of the pulverized fuel to the pulverized fuel supply pipe 26 by controlling the pulverizer 31.

The control device 65 includes, for example, a CPU (Central Processing Unit), a RAM (Random Access Memory), a ROM (Read Only Memory), and a computer-readable storage medium. A series of processing for realizing various functions is stored in a storage medium or the like in the form of a program as an example, and the CPU reads the program into a RAM or the like to execute information processing/arithmetic processing. As a result, various functions are realized. The program is installed in a ROM or other storage medium in advance, provided in a state of being stored in a computer-readable storage medium, or delivered via wired or wireless communication means. Etc. may be applied. The computer-readable storage medium is a magnetic disk, a magneto-optical disk, a CD-ROM, a DVD-ROM, a semiconductor memory, or the like.

FIG. 3 is a schematic diagram showing a rotary valve in the solid fuel supply device, and FIG. 4 is a plan view showing an arrangement configuration of the rotary valve.

As shown in FIGS. 3 and 4, the rotary valve 64 in the present embodiment includes a casing 81, an impeller 82, and an electric motor 83. An impeller 82 is arranged inside the casing 81, and the impeller 82 is rotatably supported by the casing 81 by a rotating shaft 91. The casing 81 is provided with a supply port 92 for supplying the solid fuel F to the impeller 82 at the upper part, and is provided with a discharge port 93 for discharging the solid fuel F from the impeller 82 at the lower part. The impeller 82 has a shaft support portion 94, a plurality of (for example, eight in this embodiment) blades 95, and two rotating plates 96. The shaft support portion 94 is integrally provided with the rotating shaft 91. A plurality of blades 95 are provided on the outer peripheral portion of the shaft support portion 94 at equal intervals in the circumferential direction. The two rotary plates 96 are provided on the outer peripheral portion of the shaft support portion 94 and on both sides of the plurality of blades 95 (front-back direction in the plane of FIG. 3). Therefore, the impeller 82 is provided with a plurality (eight in this embodiment) of transfer space portions 97 along the circumferential direction by the shaft support portion 94, each blade 95, and each rotary plate 96.

Further, the casing 81 is provided with a seal surface 98 having an arc shape along the outer peripheral portion of the impeller 82 between the supply port 92 and the discharge port 93. A predetermined gap is secured between the seal surface 98 and the outer peripheral portion of the impeller 82, that is, the outer peripheral portions of the blade 95 and the rotary plate 96. The length of the sealing surface 98 in the circumferential direction is set to be longer than the interval in the outer circumferential direction between the adjacent blades 95, that is, the length in the outer circumferential direction of one transport space 97. Therefore, in the rotary valve 64, a sealing function is formed between the outer peripheral portion of the impeller 82 and the sealing surface 98 of the casing 81, and the reverse flow due to the blowing up of the primary air and the fine powder fuel from the discharge port 93 side to the supply port 92 side. Is suppressed.

A support base 101 is fixed to one side of the casing 81, and an electric motor 83 is fixed onto the support base 101. In the electric motor 83, the drive sprocket 103 is fixed to the output shaft 102. The driven sprocket 104 is fixed to the rotary shaft 91 of the impeller 82. An endless drive chain 105 is wound around the drive sprocket 103 and the driven sprocket 104. Therefore, when the electric motor 83 is driven, the rotational force of the output shaft 102 is transmitted to the rotary shaft 91 via the drive sprocket 103, the drive chain 105, and the driven sprocket 104, and the impeller 82 of the rotary valve 64 is forward or reverse. Rotate to. In the present embodiment, the counterclockwise direction on the paper surface of FIG. 3 is the forward rotation of the rotary valve 64, and the clockwise direction on the paper surface of FIG. 3 is the reverse rotation.

The control panel 110 that drives and controls the electric motor 83 may be arranged near the rotary valve 64. The control panel 110 has a control device 65 (see FIG. 2) and is connected to the power supply unit 111. The control panel 110 is provided with a power switch 112 for the rotary valve 64, a forward rotation switch 113 for the rotary valve 64, and a reverse rotation switch 114 for the rotary valve 64. Further, a detector 115 for detecting the current value (or electric power value) of the electric motor 83 is provided, and the control panel 110 is provided with a display panel 116 for displaying the current value of the electric motor 83 detected by the detector 115. ..

Further, as shown in FIGS. 2 and 3, in the solid fuel supply device 60 of the first embodiment, the electric motor 83 is used as a detector for detecting the occurrence of the entrapment of fibrous or foreign matter in the rotary valve 64. The detector 115 that detects the current value functions. The detector 115 may detect the electric power value of the electric motor 83. When the detector 115 detects the entrapment of fibrous material or foreign matter, the control device 65 rotates the impeller 82 of the rotary valve 64 in the reverse direction for a predetermined time set in advance and then in the forward direction.

The radial tip of the blade 95 in the present embodiment has a sharpened shape in which the radial tip on the reverse rotation direction side forms an inclined surface. As a result, the space of the gap formed by the sealing surface 98 of the casing 81 and the radial tip of the blade 95 is reduced, and the amount of solid fuel (for example, solid fuel that is mainly pulverized) entering the gap is reduced, and the impeller 82 is reduced. The rotation resistance of can be reduced. On the other hand, since the radial tip of the blade 95 on the reverse rotation side is an inclined surface and has a sharpened shape, when the impeller 82 is continuously used in the reverse rotation, the radial direction of the blade 95 on the reverse direction side is continued. Due to the inclined surface of the tip, a force that strongly presses the solid fuel toward the sealing surface 98 side of the casing 81 acts. Therefore, when the impeller 82 is continuously rotated in the opposite direction for a long time, the solid fuel may easily adhere to the inner surface of the seal surface 98 of the casing 81. Therefore, in the rotary valve 64 in the present embodiment, the impeller 82 is preferably rotated in the forward rotation direction without continuing the reverse rotation direction for a long time.

That is, since the biomass fuel used as the solid fuel is formed by compression molding wood chips and the like, fibers such as tree bark and foreign matter such as wood chips may be mixed. Further, other foreign matter may be mixed into the solid fuel. When the fibrous matter or foreign matter is mixed in the solid fuel, the fibrous matter or foreign matter is caught in the gap between the casing 81 and the impeller 82 when the impeller 82 is rotated, and the rotation of the impeller 82 is hindered. Therefore, in the solid fuel supply device 60 of the first embodiment, when the rotary valve 64 is caught by fibrous material or foreign matter, the impeller 82 is rotated in the opposite direction, so that the gap between the casing 81 and the impeller 82 is increased. Remove any fibrous material or foreign matter that has been caught in the.

In this case, when the detector 115 detects that the electric current value of the electric motor 83 has reached the preset determination value, the detector 115 rotates the impeller 82 in the opposite direction for a predetermined time. This determination value is preferably the rated current value of the electric motor 83, for example, but may be a current value higher than the starting current value of the electric motor 83. The detector 115 may detect the electric power value instead of the electric current value of the electric motor 83.

Further, if the time for rotating in the reverse direction becomes long, the solid fuel may easily adhere to the inner surface of the seal surface 98 of the casing 81 when the impeller 82 is rotated in the reverse direction, so the predetermined time is short. Set in time. That is, the rotary valve 64 supplies the solid fuel to the pulverizer 31 via the solid fuel supply pipe 63, and the pulverizer 31 supplies the pulverized fine powder fuel to the combustion device 12 via the fine powder fuel supply pipe 26. When the impeller 82 is rotated in the opposite direction due to biting, the solid fuel is likely to adhere to the inner surface of the seal surface 98 of the casing 81 when the impeller 82 is rotated in the opposite direction for a long time continuously. Therefore, specifically, it is desirable to set the predetermined time to a time during which the impeller 82 makes a quarter rotation to a half rotation. While the impeller 82 is rotated in the opposite direction from 1/4 rotation to 1/2 rotation, the part of the impeller 82 in which the bite occurs may be vertically above the horizontal position, and the fibrous substance or the foreign matter in which the bite has occurred Are gravitationally dropped and accommodated in the transfer space 97 provided between the plurality of blades 95.

Further, the rotary valve 64 is provided with a transfer space portion 97 into which the solid fuel enters. When the impeller 82 rotates in the forward direction, it is desirable to set the amount of solid fuel contained in the transfer space 97 to be smaller than the volume of the transfer space 97. That is, as described above, when the impeller 82 is rotated in the opposite direction, the fibrous material or foreign matter removed from the gap between the casing 81 and the impeller 82 is accommodated in the transport space 97. Specifically, it is desirable that the amount of solid fuel accommodated in the transfer space 97 is set to 30% to 80% of the volume of the transfer space 97. In this case, since the amount of solid fuel supplied to the crusher 31 is set in advance, this numerical value is an outer diameter determined when the impeller 82 is designed as the amount of solid fuel accommodated in the transfer space 97. It can be set by adjusting. Further, for example, it can be set by adjusting the supply amount of the solid fuel supplied from the upper fuel supply pipe 74 by the fuel supply device 62 and the rotation speed of the impeller 82.

Further, even if the impeller 82 is rotated in the opposite direction, when the bite is not removed because the fibrous substance or the foreign matter is not removed from the gap between the casing 81 and the impeller 82, the operator does not rotate the impeller 82. It is preferable to stop and to remove the fibrous material or foreign matter caught in the gap between the casing 81 and the impeller 82. Therefore, the casing 81 is provided with the inspection port 121. The casing 81 is provided with an inspection port 121 communicating with the supply port 92 on a side portion, and a closing lid 122 is fixed to the inspection port 121 and closed.

When the detector 115 detects the entrapment of a foreign substance, the control device 65 rotates the impeller 82 in the reverse direction for a predetermined time and then in the positive direction. This operation is simulated in advance. It is possible. That is, the bite simulation switch 123 that outputs the bite detection signal to the control device regardless of the detection result of the detector 115 is provided. The entrapment simulation switch 123 is provided on the control panel 110 and can eliminate a slight entrapment of fiber or foreign matter even when the detector 115 does not detect the entrapment. Further, a series of operations in which the impeller 82 is rotated in the reverse direction for a predetermined time and then rotated in the forward direction and the control during the series of operations can be simulated and confirmed.

Here, a solid fuel supply method by the solid fuel supply device 60 of the first embodiment will be described. FIG. 5 is a flowchart showing the operation of the solid fuel supply device, FIG. 6 is a schematic view showing a foreign material biting state in the rotary valve, FIG. 7 is a schematic view showing a reverse rotation state of the rotary valve, and FIG. FIG. 4 is a schematic diagram showing a forward rotation state of the rotary valve.

In the solid fuel supply method according to the first embodiment, the step of rotating the impeller 82 to supply the solid fuel through the solid fuel supply pipe 63 and the impeller 82 set in advance when the bite in the rotary valve 64 is detected. It has a step of rotating in the reverse direction for a predetermined time and a step of rotating the impeller 82 in the forward direction after the elapse of the predetermined time.

As shown in FIGS. 3 and 5, the control device 65 activates the rotary valve 64 in step S11, and rotates the impeller 82 in the forward direction by the electric motor 83 in step S12. That is, the electric motor 83 is driven to transmit the rotational force of the output shaft 102 to the rotary shaft 91 via the drive sprocket 103, the drive chain 105, and the driven sprocket 104, thereby rotating the impeller 82 in the forward direction. The predetermined amount of solid fuel F conveyed from the fuel supplier 62 is supplied into the casing 81 from the supply port 92. In the impeller 82 that rotates at a predetermined rotation speed, the solid fuel F in an amount smaller than the volume of the transfer space 97 is stored in the transfer space 97. At this time, the sealing function is secured between the outer peripheral portion of the impeller 82 and the sealing surface 98 of the casing 81. Then, the solid fuel F stored in the transport space 97 is transported downward by the rotation of the impeller 82 and discharged from the discharge port 93.

In step S13, the controller 65 receives the current value (or power value) of the electric motor 83 from the detector 115. The control device 65 determines whether or not the current value of the electric motor 83 input from the detector 115 has reached a determination value (rated current value (or rated power value)). In this case, the control device 65 sets a preset determination time (for example, from 0.5 seconds from the time when the current value (or power value) of the electric motor 83 input from the detector 115 reaches the determination value). It is desirable to judge whether or not it has continued for 1.0 second or more. Here, if it is determined (No) that the current value (or power value) of the electric motor 83 is lower than the determination value, the routine is exited without doing anything.

On the other hand, if it is determined that the current value (or power value) of the electric motor 83 is equal to or greater than the determination value (Yes), the control device 65 causes the electric motor 83 to rotate the impeller 82 in the opposite direction in step S14. To do. As shown in FIGS. 5 and 6, when the fibrous substance or the foreign substance F1 is caught between the casing 81 and the impeller 82 that rotates in the forward direction, the impeller 82 cannot rotate in the forward direction and is electrically driven. A load acts on the motor 83 to increase the current value (or power value). When the current value (or electric power value) of the electric motor 83 rises above the determination value, the control device 65 bites the fibrous material or the foreign matter F1 between the impeller 82 and the casing 81, and bites occur. I presume. Then, at this time, as shown in FIGS. 5 and 7, when the impeller 82 is rotated in the opposite direction by the electric motor 83, the fibrous material or the foreign material F1 caught between the impeller 82 and the casing 81 falls off. Then, the impeller 82 is accommodated by falling into the transfer space 97 of the impeller 82.

In step S15, the control device 65 determines whether or not a predetermined time Tb has elapsed since the impeller 82 rotated in the reverse direction. Here, if it is determined that the predetermined time Tb has not elapsed since the impeller 82 rotates in the opposite direction (No), the process returns to step S14. On the other hand, when it is determined that the predetermined time Tb has elapsed after the impeller 82 rotates in the reverse direction (Yes), the control device 65 causes the electric motor 83 to rotate the impeller 82 in the forward direction in step S16. To do. Then, as shown in FIGS. 5 and 8, the fibrous material and the foreign matter F1 that have been caught between the impeller 82 and the casing 81 fall off and are accommodated in the transfer space 97 of the impeller 82. Therefore, the bite between the impeller 82 and the casing 81 is eliminated, the impeller 82 can rotate in the forward direction, and the supply of the solid fuel F can be restarted.

As described above, in the solid fuel supply device of the first embodiment, the solid fuel supply pipe 63 for supplying the solid fuel, and the rotary valve 64 having the rotatable impeller 82 provided on the solid fuel supply pipe 63 are provided. , The detector 115 for detecting the entrapment of the fibrous or foreign matter F1 in the rotary valve 64, and after rotating the impeller 82 in the opposite direction for a preset time Tb when the detector 115 detects the entrapment. And a control device 65 for rotating in the forward direction.

Therefore, when the impeller 82 is rotated in the forward direction and the fibrous substance or the foreign substance F1 is caught in the impeller 82, the bite is detected, and the impeller 82 is rotated in the reverse direction. The biting in is eliminated, and the fibrous substance or foreign matter F1 falls off and is accommodated in the transport space 97. Then, when the impeller 82 is rotated in the forward direction after the elapse of the predetermined time Tb, the fibrous substance or the foreign matter F1 accommodated in the transfer space 97 of the impeller 82 is re-engaged between the impeller 82 and the casing 81. Instead, the solid fuel F is properly supplied to the crusher 31 through the solid fuel supply pipe 63. As a result, the supply of the solid fuel F can be secured by suppressing all the operation stop of the rotary valve 64.

In the solid fuel supply device of the first embodiment, the predetermined time Tb for rotating in the reverse direction is set to a time shorter than the time when the crushing process of the solid fuel F by the crusher 31 is completed. Accordingly, while the rotary valve 64 causes bite of the fibrous material or the foreign material F1 to rotate the impeller 82 in the opposite direction, the pulverizer 31 continues the pulverized fuel generated by pulverizing the solid fuel F. Then, it can be supplied to the fine powder fuel supply pipe 26. After that, since the impeller 82 is rotated in the forward direction after the elapse of the predetermined time Tb, before the completion of the crushing process of the solid fuel F held in the crusher 31, the bite is eliminated and the crusher 31 is fed to the crusher 31. The supply of the solid fuel F can be restarted, and the pulverized fuel can be continuously supplied from the pulverized fuel supply pipe 26.

In the solid fuel supply device of the first embodiment, the predetermined time Tb is set to the time during which the impeller 82 makes 1/4 rotation to 1/2 rotation. Therefore, while the impeller 82 is rotated in the opposite direction from ¼ rotation to ½ rotation, the part of the impeller 82 in which the bite is generated may be vertically above the horizontal position, and the fiber material in which the bite is generated Alternatively, the foreign matter F1 is gravitationally dropped and stored in the transfer space 97 provided between the plurality of blades 95. Therefore, since the rotation in the reverse direction is not performed for a long time, the solid fuel is prevented from easily adhering to the inner surface of the seal surface 98 of the casing 81, the bite is quickly eliminated, and the solid fuel to the crusher 31 is prevented. The supply of F can be restarted.

In the solid fuel supply device of the first embodiment, when the impeller 82 rotates in the forward direction, the amount of the solid fuel F contained in the transfer space 97 is set to be smaller than the volume of the transfer space 97. Therefore, when the rotary valve 64 causes the fiber or foreign matter F1 to be caught and rotates the impeller 82 in the opposite direction, if the fiber or foreign matter F1 caught in the impeller 82 falls off, the dropped fiber Alternatively, the foreign matter F1 can be accommodated in the transport space 97, and when the impeller 82 is rotated in the forward direction after the elapse of the predetermined time Tb, the fibrous matter or the foreign matter F1 does not bite into the impeller 82 again and the solid fuel The supply of F can be restarted.

In the solid fuel supply device of the first embodiment, the amount of the solid fuel F stored in the transfer space 97 is set between 30% and 80% of the volume of the transfer space 97. Therefore, an appropriate amount of the solid fuel F can be efficiently supplied, and the fibrous substance or foreign matter F1 dropped from the gap between the impeller 82 and the sealing surface 98 that has been bitten can be properly accommodated in the transport space 97. You can

In the solid fuel supply device of the first embodiment, when the current value or the electric power value of the electric motor 83 detected by the detector 115 reaches the preset judgment value, the control device 65 causes the impeller 82 to move for a predetermined time Tb. It is rotating in the opposite direction. Therefore, based on the detection result of the existing detector 115, the bite of the fibrous substance or the foreign matter F1 in the rotary valve 64 can be detected quickly and accurately, and the increase in cost related to the detector 115 can be suppressed. it can.

In the solid fuel supply device of the first embodiment, the inspection port 121 is provided in the casing 81 that rotatably supports the impeller 82. Therefore, even if the impeller 82 is rotated in the opposite direction and the bite of the foreign matter F1 is not eliminated, the operator stops the operation of the rotary valve 64, and then the operator inserts the fibrous material into the impeller 82 through the inspection port 121. Alternatively, the foreign material F1 can be removed.

In the solid fuel supply device of the first embodiment, the disassembling upper connection portion 76 is provided on the upstream side of the rotary valve 64 in the solid fuel supply pipe 63 in the supply direction of the solid fuel F. Therefore, when the bite of the foreign substance F1 is not eliminated even if the impeller 82 is rotated in the opposite direction, the operator can stop the operation of the rotary valve 64 and then the operator can disassemble the upper connecting portion 76 (for example, a sleeve joint). By disassembling and opening the portion of the supply port 92 of the rotary valve 6, even a large fibrous substance or foreign matter F1 caught in the impeller 82 can be removed.

The solid fuel supply device of the first embodiment is provided with the bite simulation switch 123 that outputs the bite signal from the control device 65 regardless of the detection result of the detector 115. Therefore, the operator can eliminate the slight bite of the fibrous substance or the foreign matter F1 by the bite simulation switch 123 even when the detector 115 does not detect the bite. Further, regardless of the detection result of the detector 115, a biting signal may be simulated and a series of operations and controls of rotating the impeller 82 in the reverse direction for a predetermined time and then in the forward direction may be simulated and confirmed. It is possible to detect the operation failure of the rotary valve 64 in advance by performing a test operation of the impeller 82 in advance.

In the solid fuel supply device of the first embodiment, the forward rotation switch 113 of the rotary valve 64, the reverse rotation switch 114 of the rotary valve 64, and the display board 116 of the detector 115 are arranged near the rotary valve 64. .. Therefore, for example, when a large fibrous substance or a foreign substance F1 is caught, and when the work is performed with the inspection port 121 or the upper connection portion 76 removed, the operator can display the impeller 82 in either the forward or reverse direction. The forward rotation switch 113 and the backward rotation switch 114 can be easily operated while looking at the board 116.

Further, in the solid fuel supply method of the first embodiment, the step of rotating the impeller 82 to supply the solid fuel F through the solid fuel supply pipe 63, and the bite of the fibrous substance or the foreign matter F1 in the rotary valve 64. When the impeller is detected, the step includes rotating the impeller 82 in the reverse direction for a predetermined time Tb set in advance, and the step of rotating the impeller 82 in the forward direction after the elapse of the predetermined time Tb. Therefore, the supply of the solid fuel F can be secured by suppressing all the operation stop of the rotary valve 64.

The crusher of the first embodiment also includes a solid fuel supply device 60. Therefore, the solid fuel F can be continuously supplied to the boiler 10.

Further, the boiler according to the first embodiment includes the solid fuel supply device 60. Therefore, the solid fuel supply device 60 can maintain and continue the supply of the solid fuel F to the boiler 10, and the stable operation of the boiler 10 can be continued.

[Second Embodiment]
FIG. 9 is a flowchart showing the operation of the solid fuel supply device of the second embodiment, and FIG. 10 is a time chart showing the operation of the solid fuel supply device. The basic configuration of the solid fuel supply device of the second embodiment is the same as that of the solid fuel supply device 60 of the first embodiment described above, and will be described with reference to FIGS. 2 and 3 and described above. Members having the same functions as those in the embodiment are designated by the same reference numerals, and detailed description thereof will be omitted.

In the solid fuel supply device 60 of the second embodiment, as shown in FIGS. 9 and 10, the control device 65, when the number of times the impeller 82 is rotated in the reverse direction exceeds a preset predetermined number of reverse rotations, The rotation of the impeller 82 is stopped. When the detector 115 detects the bite, the control device 65 rotates the impeller 82 in the reverse direction for a predetermined time Tb and then rotates it in the positive direction. The inching rotation operation causes the control device 65 to bite in the rotary valve 64. When the jamming is not eliminated, the inching rotation operation of the impeller 82, which is the reverse rotation and the forward rotation, is repeated. At this time, the control device 65 stops the rotation of the impeller 82 when the inching rotation operation of the impeller 82 exceeds a predetermined reverse rotation number (for example, 3 times) within a preset predetermined time. That is, if the bite is not eliminated even after the inching rotation operation of the impeller 82 is repeated, the rotation of the impeller 82 is stopped and the operator manually removes the fibrous substance or the foreign material F1 bitten into the impeller 82. Remove.

Further, when the control device 65 rotates the impeller 82 in the opposite direction for a predetermined time Tb, when the detector 115 detects a bite during the predetermined time Tb, the control device 65 stops the rotation of the impeller 82. When the detector 115 detects the bite, the control device 65 rotates the impeller 82 in the reverse direction for a predetermined time Tb, but when the reverse rotation operation causes the fiber or foreign matter to be bitten into the impeller 82 again, The rotation of the impeller 82 is stopped. That is, if the bite is not eliminated even if the impeller 82 is rotated in the reverse direction, the rotation of the impeller 82 is stopped, and the operator manually removes the fibrous material or the foreign material F1 bitten into the impeller 82. ..

More specifically, as shown in FIG. 9, the control device 65 activates the rotary valve 64 in step S21, and rotates the impeller 82 in the forward direction by the electric motor 83 in step S22. Then, the solid fuel F conveyed from the fuel supplier 62 and supplied from the supply port 92 into the casing 81 is accommodated in the conveying space 97 of the impeller 82 rotating at a predetermined rotation speed, and the impeller 82 rotates. Is conveyed to the lower side and discharged from the discharge port 93.

In step S23, it is determined whether or not the forward rotation duration of the impeller 82 (forward rotation time) exceeds a preset predetermined time Ta (for example, 10 seconds). Here, if it is determined that the normal rotation time of the impeller 82 does not exceed the predetermined time Ta), the control device 65 causes the control device 65 to input the current value of the electric motor 83 (from the detector 115) in step S24. Alternatively, it is determined whether the power value has reached a determination value (rated current value (or rated power value)). Here, if it is determined (No) that the current value (or power value) of the electric motor 83 is lower than the determination value, the routine is exited without doing anything.

On the other hand, if it is determined that the current value (or power value) of the electric motor 83 is equal to or greater than the determination value (Yes), the controller 65 causes the impeller 82 to rotate in the reverse direction (reverse rotation) in step S25. It is determined whether or not the number of times exceeds a predetermined number of times of reverse rotation set in advance (for example, 3 times). Here, if it is determined that the number of reverse rotations of the impeller 82 does not exceed the predetermined number of reverse rotations (No), the control device 65 causes the electric motor 83 to rotate the impeller 82 in the opposite direction in step S26. The control device 65 estimates that the fibrous or foreign material F1 is caught between the impeller 82 and the casing 81 when the current value (or electric power value) of the electric motor 83 rises above the determination value. Then, at this time, when the impeller 82 is rotated in the opposite direction by the electric motor 83, the fibrous material or the foreign matter F1 that has been caught between the impeller 82 and the casing 81 falls off, and the transfer space portion 97 of the impeller 82. It falls inside and is stored.

In step S27, control device 65 determines whether or not the current value (or power value) of electric motor 83 input from detector 115 has reached the determination value (rated current value (or rated power value)). .. Here, if it is determined (No) that the current value (or power value) of the electric motor 83 is lower than the determination value, in step S28, the control device 65 causes the impeller 82 to rotate in the opposite direction and then to the predetermined value. It is determined whether the time Tb has elapsed. If it is determined (No) that the predetermined time Tb has not elapsed since the impeller 82 rotates in the opposite direction (No), the process returns to step S26. On the other hand, if it is determined that the predetermined time Tb has elapsed since the impeller 82 rotates in the reverse direction (Yes), the number of reverse rotations of the impeller 82 is incremented by 1 in step S29. Then, in step S30, control device 65 causes electric motor 83 to rotate impeller 82 in the forward direction. Then, since the foreign matter F1 that has been caught between the impeller 82 and the casing 81 is accommodated in the transport space 97 of the impeller 82, the foreign matter F1 is formed between the impeller 82 and the casing 81. By removing the bite of the foreign matter F1, the impeller 82 can rotate in the forward direction, and the supply of the solid fuel F can be restarted.

On the other hand, when it is determined in step S23 that the forward rotation duration of the impeller 82 (forward rotation time) exceeds the predetermined time Ta (for example, 10 seconds) (Yes), the blade added in step S29. The number of reverse rotations of the car 82 is reset. However, if it is determined in step S25 that the number of reverse rotations of the impeller 82 has exceeded the predetermined number of reverse rotations (for example, 3 times) (Yes), the rotation of the impeller 82 is stopped in step S32. In step S27, it is determined that the current value (or power value) of the electric motor 83 has reached the determination value (rated current value (or rated power value)) while the impeller 82 is rotating in the reverse direction. If (Yes), the rotation of the impeller 82 is stopped in step S32.

Here, the operation of the above-described solid fuel supply device will be described with a time chart. As shown in FIG. 10, when the rotary valve 64 is activated at time t0 and the electric motor 83 rotates the impeller 82 in the forward direction, the current value of the electric motor 83 increases. At time t1, the current value of the electric motor 83 rises to the starting current value, and then falls to the steady operation current value. Then, the rotary valve 64 operates normally and supplies the solid fuel F to the crusher 31.

At time t2, the fibrous or foreign material F1 is caught between the impeller 82 and the casing 81, so that the current value of the electric motor 83 increases, and at time t3, the current value of the electric motor 83 becomes the determination value. Reach (rated current value). Then, at time t4 when a predetermined time (for example, 0.5 second to confirm that it is not instantaneous) is reached after the current value of the electric motor 83 reaches the determination value (rated current value), The electric motor 83 rotates the impeller 82 in the opposite direction. The period T1 from time t0 to time t4 is the forward rotation of the impeller 82.

When the impeller 82 is rotated in the opposite direction by the electric motor 83 at time t4, the current value of the electric motor 83 increases. At time t5, the current value of the electric motor 83 rises to the starting current value and then falls to the steady operation current value. The electric motor 83 rotates the impeller 82 in the forward direction at a time t6 when a predetermined time Tb has elapsed after the impeller 82 rotated in the reverse direction at the time t4 (stopping the rotation in the forward direction). .. At time t6, the electric motor 83 rotates the impeller 82 in the opposite direction, and the current value of the electric motor 83 increases. At time t7, the current value of the electric motor 83 rises to the starting current value and then falls to the steady operation current value. After that, when the biting of the fibrous substance or the foreign matter F1 in the rotary valve 64 is released, the rotary valve 64 operates normally and supplies the solid fuel F to the crusher 31. The period T2 from the time t4 to the time t6 is the reverse rotation of the impeller 82 and is equal to the predetermined time Tb, and the period T3 after the time t6 is the positive rotation of the impeller 82.

On the other hand, at time t4, when the impeller 82 is rotated in the opposite direction by the electric motor 83 and the current value of the electric motor 83 increases, the current value of the electric motor 83 does not decrease at the starting current value and the determination value ( When the rated current value) is reached, the rotation of the impeller 82 is stopped because the bite of the fibrous material or the foreign material F1 in the rotary valve 64 continues without being eliminated. Further, at time t4, the impeller 82 is rotated in the opposite direction by the electric motor 83, the current value of the electric motor 83 increases, the current value of the electric motor 83 decreases at the starting current value, and then increases again. When the judgment value (rated current value) is reached, the rotation of the impeller 82 is stopped because the fibrous substance or the foreign matter F1 is again caught when the impeller 82 rotates in the opposite direction.

Further, when the number of reverse rotations of the impeller 82 exceeds a predetermined number of reverse rotations (for example, 3 times) within a predetermined time, the rotation of the impeller 82 is stopped.

As described above, in the solid fuel supply device according to the second embodiment, the control device 65 stops the rotation of the impeller 82 when the number of times the impeller 82 is rotated in the reverse direction exceeds a preset predetermined number of reverse rotations. Therefore, by stopping the operation of the rotary valve 64 when the bite of the fibrous material or the foreign material F1 in the rotary valve 64 is not eliminated, it is possible to prevent damage or failure of the rotary valve 64 in advance.

In the solid fuel supply device of the second embodiment, when the impeller 82 is rotated in the opposite direction for the predetermined time Tb, the control device 65 causes the detector 115 to bite the fibrous substance or the foreign matter F1 during the predetermined time Tb. When detected, the rotation of the impeller 82 is stopped. Therefore, when the bite cannot be eliminated even if the impeller 82 is rotated in the opposite direction for the predetermined time Tb, an abnormality of the rotary valve 64 itself is considered. Therefore, by stopping the operation of the rotary valve 64 at this time, It is possible to prevent damage or failure of the rotary valve in advance.

In the above-described embodiment, the detector 115 that detects the current value or the electric power value of the electric motor 83 is applied as the detector that detects the bite of the fiber material or the foreign matter F1 in the rotary valve 64. It is not limited to the configuration. For example, a detector that detects the rotational speed of the impeller 82, a detector that detects the load (torque) of the impeller 82, or the like may be used as the detector that detects the bite in the rotary valve 64. Further, a camera may be applied as a detector that detects the entrapment of the foreign matter F1 in the rotary valve 64.

10 Boiler 11 Furnace 12 Combustor 13 Flue 21, 22, 23, 24, 25 Combustion burner 26, 27, 28, 29, 30 Fine powder fuel supply pipe 31, 32, 33, 34, 35 Crusher (mill)
60 Solid Fuel Supply Device 61 Bunker 62 Fuel Supply Machine 63 Solid Fuel Supply Pipe 64 Rotary Valve 65 Control Device 71 Down Spout Part 72 Conveying Part 73 Electric Motor 74 Upper Fuel Supply Pipe 75 Lower Fuel Supply Pipe 76 Upper Connecting Part (Connecting Part)
77 Lower Connecting Part 81 Casing 82 Impeller 83 Electric Motor 91 Rotating Shaft 92 Supply Port 93 Discharging Port 94 Shaft Support 95 Blades 96 Rotating Plate 97 Transport Space 98 Sealing Surface 110 Control Panel 111 Power Supply 112 Power Switch 113 Forward Rotation Switch 114 Reverse rotation switch 115 Detector 116 Display panel 121 Inspection port 122 Closing lid 123 Biting simulation switch F Solid fuel F1 Fiber or foreign matter

Claims (15)

A solid fuel supply pipe for supplying solid fuel;
A rotary valve having a rotatable impeller provided in the solid fuel supply pipe;
A detector for detecting the biting in the rotary valve,
When the detector detects a bite, a control device that rotates the impeller in the reverse direction for a predetermined time set in advance and then rotates in the forward direction,
A solid fuel supply device comprising: The solid fuel supply pipe is provided with a crusher on the downstream side in the solid fuel supply direction, and the predetermined time is set to a time shorter than the time when the crushing process of the solid fuel by the crusher is completed. The solid fuel supply device according to claim 1. The solid fuel supply device according to claim 2, wherein the predetermined time is set to a time between a quarter rotation and a half rotation of the impeller. The amount of the solid fuel stored in the transfer space provided between the plurality of blades when the impeller is rotated in the forward direction is set to be smaller than the volume of the transfer space. The solid fuel supply device according to any one of claims 1 to 3. The solid fuel supply device according to claim 4, wherein the amount of the solid fuel contained in the transfer space is set to 30% to 80% of the volume of the transfer space. An electric motor that drives and rotates the impeller, the detector detects a current value or an electric power value of the electric motor, and the controller sets a current value or an electric power value of the electric motor in advance. The solid fuel supply device according to any one of claims 1 to 5, wherein when the judgment value is reached, the impeller is rotated in the opposite direction for the predetermined time. 7. The control device stops the rotation of the impeller when the number of times of rotating the impeller in the reverse direction exceeds a preset number of times of reverse rotation set in advance. The solid fuel supply device according to claim 1. The control device stops the rotation of the impeller when the detector detects a bite during the predetermined time when rotating the impeller in the opposite direction for the predetermined time. Item 8. The solid fuel supply device according to any one of items 1 to 7. 9. The solid fuel supply device according to claim 1, wherein an inspection port is provided in a casing that rotatably supports the impeller. The solid fuel supply pipe according to any one of claims 1 to 9, wherein a decomposable connection portion is provided upstream of the rotary valve in the solid fuel supply pipe in a supply direction of the solid fuel. Supply device. 11. The solid fuel supply device according to claim 1, further comprising a bite simulation switch that outputs a bite signal to the control device regardless of a detection result of the detector. .. The forward rotation switch of the rotary valve, the reverse rotation switch of the rotary valve, and the display panel of the detector are arranged in the vicinity of the rotary valve. The solid fuel supply device according to claim 1. In a solid fuel supply device provided with a rotary valve having a rotatable impeller in a solid fuel supply pipe for supplying solid fuel,
Rotating the impeller to supply the solid fuel through the solid fuel supply pipe;
Detecting the biting at the rotary valve, rotating the impeller in the opposite direction for a predetermined time set in advance,
Rotating the impeller in the forward direction after the predetermined time has passed,
A solid fuel supply method comprising: A crusher comprising the solid fuel supply device according to any one of claims 1 to 12. A boiler comprising the solid fuel supply device according to any one of claims 1 to 12.

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