JPH05149526A - Pulverized - Google Patents

Abstract

PURPOSE:To make it possible to control the whole operation of a boiler and stabilize the combustion of a burner by detecting the flow rate of pulverized coal and the presence of pulverized coal on the way of a pulverized coal pipeline which carries pulverized coal from a pulverized coal mill to a burner and controlling the pulverized coal and the burner based on the detection results. CONSTITUTION:A detector 26, which detects the flow rate of dust coal 4 and the presence of pulverized coal 4 by sampling pulverized coal 4 in continuous mode, is installed on the way of a pulverized coal pipeline 5. An arithmetic operation control device 30 transmits a control command 28 to at least either a table rotation device 18 of pulverized coal mill 3, a screw down setting device 21 or a classification force control device 23 based on a detection signal 27 transmitted from the detector 26. Furthermore, the control device 30 transmits one control command 29 at least to either an air flow rate control device 9 of a burner 2 or a pulverized coal concentration control device 16. This construction makes it possible to control the properties of duct coal properly and maintain stabilized combustibility of the burner.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a pulverized coal device.

[0002]

2. Description of the Related Art Generally, in a pulverized coal burning boiler, raw coal is pulverized in a pulverized coal mill to produce pulverized coal as a fuel just before combustion in a burner. The properties such as the concentration and fineness of the pulverized coal were not adequately controlled, and the properties of the pulverized coal were left to leave.

[0003]

However, since the properties of the pulverized coal produced by the pulverized coal mill greatly change when the pulverized coal mill is started and stopped or when the load changes, the properties of the pulverized coal are sufficiently controlled. Otherwise, it may be difficult to control the pulverized coal burning boiler as a whole and to stably burn the burner.

In recent years, a burner has been developed which can concentrate and burn the pulverized coal having a low concentration sent from the pulverized coal mill when the pulverized coal mill is under a low load. Such a burner is used. In this case, if the pulverized coal is not used after being sufficiently controlled in properties, there is a possibility that stable combustion of the burner may not be obtained or the pulverized coal may be clogged inside the burner.

In view of the above situation, it is an object of the present invention to provide a pulverized coal device capable of detecting the properties of pulverized coal and controlling the pulverized coal mill and burner.

[0006]

According to a first aspect of the present invention, a detector for detecting the flow rate and the fineness of the pulverized coal is provided in the middle of the pulverized coal pipe for conveying the pulverized coal from the pulverized coal mill to the burner. The present invention relates to a pulverized coal device characterized in that an arithmetic and control unit for sending a control command to the pulverized coal mill based on a detection signal from the unit is provided.

According to a second aspect of the present invention, a detector for detecting the flow rate and fineness of the pulverized coal is provided in the middle of the pulverized coal pipe for conveying the pulverized coal from the pulverized coal mill to the burner, and based on the detection signal from the detector. The present invention relates to a pulverized coal device characterized in that an arithmetic and control unit for sending a control command to the burner is provided.

[0008]

According to the invention of claim 1, the flow rate and the fineness of the pulverized coal are detected by the detector provided in the middle of the pulverized coal pipe for conveying the pulverized coal from the pulverized coal mill to the burner, and the detector The arithmetic and control unit sends a control command to the pulverized coal mill based on the detection signal, whereby the pulverized coal mill is controlled.

According to the invention of claim 2, the flow rate and the fineness of the pulverized coal are detected by a detector provided in the middle of the pulverized coal pipe for conveying the pulverized coal from the pulverized coal mill to the burner. The burner is controlled by the arithmetic and control unit sending a control command to the burner based on the detection signal.

[0010]

Embodiments of the present invention will be described below with reference to the drawings.

1 to 3 show an embodiment of the present invention.

In the figure, 1 is a pulverized coal burning boiler, 2 is a burner provided in the pulverized coal burning boiler 1, 3 is a pulverized coal mill for pulverizing raw coal to produce pulverized coal 4 as fuel, and 5 is pulverized powder. It is a pulverized coal pipe that feeds the pulverized coal 4 produced by the coal mill 3 to the burner 1 by using the conveying air 6.

As shown in FIG. 2, the burner 2 has a damper 32 capable of adjusting the amount of combustion air 10 supplied to a port 8 formed in the furnace wall 7 of the pulverized coal burning boiler 1 by an air flow rate adjusting device 33. Is attached, an air register 11 capable of adjusting the swirling force of the combustion air 10 by an air swirling force adjusting device 9 is attached to the wake of the damper, and the air register 11 is manufactured by a pulverized coal mill 3 at the center thereof. The burner body 12 capable of injecting the pulverized coal 4 is inserted and arranged, and the separation cylinder 13 capable of separating the pulverized coal 4 and the conveying air 6 is disposed at the tip end position inside the burner body 12, and the burner body 12 internal shaft A pulverized coal concentration adjusting ring 15 is movably fitted over the pulverized coal nozzle inner cylinder 14 arranged at the center position, and the pulverized coal concentration adjusting device 1 such as a cylinder is attached to the pulverized coal concentration adjusting ring 15.
6 is connected to the pulverized coal 4 injected from the burner body 12 so that the combustion air 10 supplied to the air register 11 is mixed and burned. The supply amount of the combustion air 10 can be adjusted by adjusting the opening degree, and the swirling of the combustion air 10 can be performed by adjusting the opening degree of the air register 11 by the air swirling force adjusting device 9. The force can be adjusted, and further, by moving the position of the pulverized coal concentration adjusting ring 15 by the pulverized coal concentration adjusting device 16, the pulverized coal 4 supplied to the burner main body 12 and the conveying air 6 are separated. It can be centrifuged.

Further, in the pulverized coal mill 3, as shown in FIG. 3, the raw coal 20 is dropped from the upper part of the mill body 17 onto a crushing table 19 which is driven to rotate by a table rotating device 18 such as a motor. The raw coal 20 dropped on the crushing table 19 is crushed using a crushing roller 22 whose rolling force is adjusted by a rolling force adjusting device 21, and the crushed raw coal 20 is supplied from the lower part of the mill body 17 for transportation. The raw coal 20 blown up by the air 6 and crushed and blown up is classified into the pulverized coal 4 and the pulverized coal 25 by using the rotary classifier 24 whose classification power is adjusted by the classification power adjusting device 23. Only the pulverized coal pipe 5 is sent out.

A detector 26 for continuously sampling the pulverized coal 4 to detect the flow rate and the fineness of the pulverized coal 4 is provided in the middle of the pulverized coal pipe 5, and a detection signal 27 from the detector 26 is provided. Based on the table rotating device 18 of the pulverized coal mill 3
A control command 28 is sent to at least one of the pressure reducing device 21, the classification force adjusting device 23, and the classifying force adjusting device 23, and a control command 29 is issued to at least one of the air flow rate adjusting device 9 and the pulverized coal concentration adjusting device 16 of the burner 2. An arithmetic and control unit 30 for sending is provided.

Next, the operation will be described.

The pulverized coal 4 produced in the pulverized coal mill 3 is fed to the burner 2 via the pulverized coal pipe 5 and burned in the burner 2.

The pulverized coal 4 flowing through the pulverized coal pipe 5 is
On the way, the detector 26 continuously samples to detect the flow rate and fineness.

Detection signal 2 detected by the detector 26
7 is sent to the arithmetic and control unit 30. The arithmetic and control unit 30 adjusts the flow rate (production amount) and fineness of the pulverized coal 4 and the table rotating device 18 of the pulverized coal mill 3, the rolling force adjusting device 21, and the classification. The control command 28 is sent to at least one of the force adjusting devices 23, and the air flow rate adjusting device 33 and the air swirling force adjusting device of the burner 2 are adjusted so that stable combustion is performed based on the current flow rate and fineness of the pulverized coal 4. A control command 29 is sent to at least one of the device 9 and the pulverized coal concentration adjusting device 16.

Then, in the pulverized coal mill 3, when the flow rate of the pulverized coal 4 is small according to the control command 28, the rotation speed of the pulverization table 19 is increased or the rolling force of the pulverization roller 22 is increased to increase the raw coal. Or increase the crushing power to 20
If the flow rate of the pulverized coal 4 is increased by lowering the rotation speed of the rotary classifier 24 to reduce the classification force, on the contrary, when the flow rate of the pulverized coal 4 is high, the rotation speed of the crushing table 19 is decreased, The flow rate of the pulverized coal 4 is reduced by reducing the rolling force of the crushing roller 22 to reduce the crushing force on the raw coal 20, or by increasing the rotation speed of the rotary classifier 24 to increase the classification force.
When the fineness of the pulverized coal 4 is low (the average particle size is large), the crushing force on the raw coal 20 is increased by increasing the rotation speed of the crushing table 19 or increasing the rolling force of the crushing roller 22. The fineness of the pulverized coal 4 is increased by increasing the number of revolutions of the rotary classifier 24 or increasing the classification power, and conversely, when the fineness of the pulverized coal 4 is high (the average particle diameter is small). Is to reduce the rotation speed of the crushing table 19 or reduce the rolling force of the crushing roller 22 to increase the crushing force on the raw coal 20, or reduce the rotation speed of the rotary classifier 24 to reduce the classification force. To reduce the fineness of the pulverized coal 4.

As a result, the properties of the pulverized coal 4 produced in the pulverized coal mill 3 are sufficiently controlled, so that the controllability of the pulverized coal-fired boiler 1 as a whole is improved and the stable burnability of the burner 2 is secured. It

In the burner 2, the control command 29 causes
When the flow rate of the pulverized coal 4 is small (the concentration is low), the opening of the damper 32 is reduced to reduce the amount of the combustion air 10, or the opening of the air register 11 is reduced to reduce the combustion air 10. Ring for adjusting pulverized coal concentration to weaken turning force
5 is moved (the side to be moved depends on the shape of the burner body 12) to promote the separation of the pulverized coal 4 and the conveying air 6 to increase the concentration, and conversely, the flow rate of the pulverized coal 4 is large. When the concentration is high, the damper 32 is opened to increase the amount of the combustion air 10 or the air register 11 is increased to increase the swirling force of the combustion air 10, or The position of the coal concentration adjusting ring 15 is moved to prevent separation of the pulverized coal 4 and the conveying air 6, and when the pulverized coal 4 has a high fineness, the pulverized coal concentration adjusting ring 15 is used. Is moved so that the pulverized coal 4 does not block the passage 31 between the burner body 12 and the separation cylinder 13.

As a result, the stable burnability of the burner 2 is secured even when the properties of the pulverized coal 4 change suddenly.

The present invention is not limited to the above-mentioned embodiments, and it goes without saying that various modifications can be made without departing from the gist of the present invention.

[0025]

As described above, according to the inventions of claims 1 and 2, it is possible to obtain an excellent effect that the property of pulverized coal can be detected to control the pulverized coal mill and the burner.

[Brief description of drawings]

FIG. 1 is a schematic overall view of an embodiment of the present invention.

2 is a schematic view of the burner of FIG. 1. FIG.

FIG. 3 is a schematic view of the pulverized coal mill of FIG. 1.

[Explanation of symbols]

 2 Burner 3 Pulverized coal mill 4 Pulverized coal 5 Pulverized coal tube 26 Detector 27 Detection signal 28, 29 Control command 30 Arithmetic control device

 ─────────────────────────────────────────────────── ─── Continuation of the front page (72) Inventor Tetsuo Ono 2-24-15 Tenjin-cho, Fujisawa-shi, Kanagawa Parkside Tenjin 103 (72) Inventor Naoshi Kimura, 2-16 Toyosu, Koto-ku, Tokyo Haruma Ishikawajima Heavy Industries Co., Ltd. Toyosu General Office (72) Inventor Keiji Makino 3-2-16 Toyosu, Koto-ku, Tokyo Ishikawajima Harima Heavy Industries Co., Ltd. Toyosu General Office (72) Inventor Yuzuru Yuzawa 3-chome, Toyosu, Koto-ku, Tokyo No. 16 Ishikawajima Harima Heavy Industries Co., Ltd.Toyosu General Office

Claims (2)

[Claims] 1. A pulverized coal pipe for conveying pulverized coal from the pulverized coal mill to a burner is provided with a detector for detecting the flow rate and fineness of the pulverized coal, and the pulverized coal mill is connected to the pulverized coal mill based on a detection signal from the detector. A pulverized coal device, which is provided with an arithmetic and control unit for sending a control command. 2. A detector for detecting a pulverized coal flow rate and a fineness is provided in the middle of a pulverized coal pipe for conveying pulverized coal from the pulverized coal mill to the burner, and a control command is issued to the burner based on a detection signal from the detector. A pulverized coal device characterized in that it is provided with an arithmetic and control unit for sending the.