CN217512031U

CN217512031U - Coal mill

Info

Publication number: CN217512031U
Application number: CN202221347678.3U
Authority: CN
Inventors: 任利明; 胡金顶; 杜学森; 李源; 李威; 毛睿
Original assignee: Rundian Energy Science and Technology Co Ltd
Current assignee: Rundian Energy Science and Technology Co Ltd
Priority date: 2022-05-30
Filing date: 2022-05-30
Publication date: 2022-09-30
Anticipated expiration: 2032-05-30

Abstract

The utility model relates to a coal grinding equipment technical field discloses a coal pulverizer, and it includes: the coal pulverizer comprises an air compressor, a coal pulverizer body, a coal powder conveying pipe and an air pipe for conveying air into the coal powder conveying pipe; the input port of the air pipe is communicated with the air compressor, and the output port of the air pipe is communicated with the pulverized coal conveying pipe; and an air volume control mechanism for controlling the air volume of the air pipe is arranged in the air pipe. The embodiment of the utility model provides a through control system control amount of wind control mechanism, make the amount of wind and the wind speed that the amount of wind control mechanism control tuber pipe got into the buggy conveyer pipe, thereby intervene the flow field in the buggy conveyer pipe, realize that the control is got into the buggy volume of buggy conveyer pipe and the purpose of adjusting the buggy concentration in the buggy conveyer pipe by the coal pulverizer body, make the coal pulverizer body carry the buggy concentration and the buggy volume in each buggy conveyer pipe can keep basic unanimity.

Description

Coal mill

Technical Field

The utility model relates to a coal grinding equipment technical field especially relates to a coal pulverizer.

Background

At present, in a large coal-fired boiler, the concentration uniformity of pulverized coal among primary air pipes of burners on the same layer is directly related to the combustion characteristics of pulverized coal in the boiler. The coal powder distributed uniformly can reduce the non-uniform combustion in the boiler, and prevent the boiler corrosion and boiler tube explosion caused by thermal deviation and slag bonding. However, in actual operation, due to the positions of the coal mill and the powder exhauster and the field arrangement of other equipment in the coal-fired power plant, the directions of the powder feeding pipelines from the outlet of the coal mill to the combustion port of the boiler furnace are relatively different, and the resistances of the pipelines for conveying coal powder are different, so that the phenomenon of uneven distribution of air and powder among the powder feeding pipelines is formed, the combustion of the boiler is directly influenced, and the safety and the economical efficiency of unit operation are seriously influenced.

At present, the coal-fired power plant in China can not realize on-line measurement on the concentration of the pulverized coal in the pulverized coal conveying pipe. The coal powder conveying pipes at the outlet of the existing coal mill are all provided with manually adjustable shrinkage holes, and the powder feeding amount of each coal powder conveying pipe is adjusted by changing the flow sectional area, so that the aim of uniformly feeding the powder is fulfilled. However, the shrinkage cavity adjusting function is limited, the manual adjusting operation amount is large, the process is complicated, and the requirements of deep peak regulation and flexible transformation cannot be met. Therefore, improvement and innovation thereof are imperative.

SUMMERY OF THE UTILITY MODEL

The to-be-solved technical problem of the utility model is: in actual operation, due to the positions of the coal mill body and the powder exhauster and the field arrangement condition of other equipment of the coal-fired power plant, the coal powder trend in each powder feeding pipeline from the outlet of the coal mill body to the combustion spraying port of the boiler hearth is relatively large, the pipeline resistance for conveying the coal powder is different, the phenomenon of uneven air-powder distribution among the powder feeding pipelines is formed, and the boiler combustion is directly influenced.

In order to solve the technical problem, the utility model provides a coal pulverizer, it includes: the coal pulverizer comprises an air compressor, a coal pulverizer body, a coal powder conveying pipe and an air pipe for conveying air into the coal powder conveying pipe; the input port of the air pipe is communicated with the air compressor, and the output port of the air pipe is communicated with the pulverized coal conveying pipe; an air quantity control mechanism for controlling the air quantity of the air pipe is arranged in the air pipe; the number of the air pipes is multiple; the number of the coal dust conveying pipes is multiple; the coal mill body is provided with a plurality of coal outlets; the plurality of air pipes, the plurality of coal powder conveying pipes and the plurality of coal mill bodies are arranged in a one-to-one correspondence manner; each coal dust conveying pipe is communicated with one coal outlet.

Optionally, the method further includes: the pulverized coal concentration measuring device is used for measuring the concentration of pulverized coal in the pulverized coal conveying pipe, and the control system is used for controlling the air volume control mechanism according to the concentration of the pulverized coal; the number of the pulverized coal concentration measuring devices is multiple; the plurality of coal dust concentration measuring devices are arranged in one-to-one correspondence with the plurality of coal dust conveying pipes.

Optionally, the pulverized coal concentration measuring device includes: the system comprises a pulverized coal sampling pipe, a gas-solid separator, a solid weighing device, a first control valve, a flowmeter and an air pump; the gas-solid separator is provided with a raw material inlet, a gas outlet and a solid outlet;

the input end of the pulverized coal sampling pipe is communicated with the pulverized coal conveying pipe, and the output end of the pulverized coal sampling pipe is communicated with the raw material inlet of the gas-solid separator; the solid weighing device is arranged below the solid outlet; the flowmeter is communicated with a gas outlet of the solid weighing device through a first pipeline; the first control valve is arranged on the first pipeline; the flowmeter is communicated with the air extracting pump through a second pipeline.

Optionally, the air volume control mechanism includes: a second control valve; the air compressor is respectively communicated with the input ports of the air pipes; the second control valve is arranged on the air pipe.

Optionally, the air volume control mechanism includes: a motor, a first pivot, and a first baffle; the first baffle is pivoted in the air pipe through a first pivot; an output shaft of the motor is coaxially connected with the first pivot; the motor is electrically connected with the control system.

Optionally, the method further includes: a second baffle and a second pivot; the coal dust conveying pipes are divided into a first part coal dust conveying pipe and a second part coal dust conveying pipe which are arranged on two opposite sides of a preset plane;

the second baffle is pivoted in the coal mill body through the second pivot; the axis of the second pivot is positioned in the preset plane; the second baffle plate is provided with a plurality of through holes for coal powder to pass through; the second baffle has a first state and a second state;

under the condition that the second baffle is in the first state, the second baffle is positioned in a first conveying channel of the coal mill body for conveying the coal powder to the first part of coal powder conveying pipe;

and under the condition that the second baffle is in the second state, the second baffle is positioned in a second conveying passage for conveying the coal dust to the second part of coal dust conveying pipe of the coal mill body.

Optionally, the second baffle is a wear-resistant liner plate.

Optionally, the area of the through hole accounts for 70% of the area of the second baffle.

The embodiment of the utility model provides a coal pulverizer compares with prior art, and its beneficial effect lies in:

the embodiment of the utility model provides a through control system control amount of wind control mechanism, make the amount of wind and the wind speed that the amount of wind control mechanism control tuber pipe got into the buggy conveyer pipe, thereby intervene the flow field in the buggy conveyer pipe, realize that the control is got into the buggy volume of buggy conveyer pipe and the purpose of adjusting the buggy concentration in the buggy conveyer pipe by the coal pulverizer body, make the coal pulverizer body carry the buggy concentration and the buggy volume in each buggy conveyer pipe can keep basic unanimity.

Drawings

Fig. 1 is a schematic structural diagram of an embodiment of the present invention;

FIG. 2 is a top view of a pulverized coal conveying pipe according to an embodiment of the present invention;

FIG. 3 is a schematic structural diagram of a second baffle plate in the embodiment of the present invention;

FIG. 4 is a schematic structural view of an air duct according to an embodiment of the present invention;

fig. 5 is a schematic structural diagram of a pulverized coal concentration measuring device in an embodiment of the present invention;

fig. 6 is a schematic structural diagram of an air duct according to another embodiment of the present invention.

In the drawing, 1, a coal mill body; 2. a pulverized coal conveying pipe; 3. an air duct; 4. the hole can be reduced; 5. an air volume control mechanism; 51. a motor; 52. a first pivot; 53. a first baffle plate; 54. a second control valve; 6. a second baffle; 61. a through hole; 7. a second pivot; 8. a pulverized coal concentration measuring device; 81. a pulverized coal sampling pipe; 82. a gas-solid separator; 83. a solid weighing device; 84. a first control valve; 85. a flow meter; 86. an air pump.

Detailed Description

The following detailed description of the embodiments of the present invention is provided with reference to the accompanying drawings and examples. The following examples are intended to illustrate the invention, but are not intended to limit the scope of the invention.

First, it should be noted that the orientations of top, bottom, upward, downward, and the like referred to herein are defined with respect to the orientation in the respective drawings, are relative concepts, and thus can be changed according to different positions and different practical states in which they are located. These and other orientations, therefore, should not be used in a limiting sense.

It should be noted that the term "comprising" does not exclude other elements or steps and the "a" or "an" does not exclude a plurality.

Furthermore, it should be further noted that any single technical feature described or implied in the embodiments herein, or any single technical feature shown or implied in the figures, can still be combined between these technical features (or their equivalents) to obtain other embodiments of the present application not directly mentioned herein.

It will be further understood that the terms "first," "second," and the like, are used herein to describe various information and should not be limited to these terms, which are used only to distinguish one type of information from another. For example, "first" information may also be referred to as "second" information, and similarly, "second" information may also be referred to as "first" information, without departing from the scope of the present application.

It should be noted that in different drawings, the same reference numerals indicate the same or substantially the same components.

As shown in fig. 1, a coal pulverizer according to a preferred embodiment of the present invention includes: the coal pulverizer comprises a control system, an air compressor (not shown), a coal pulverizer body 1, a plurality of coal powder conveying pipes 2 and a plurality of air pipes 3 for conveying air into the coal powder conveying pipes 2. The input port of tuber pipe 3 with the air compressor machine is linked together, and the delivery outlet of tuber pipe 3 is linked together with buggy conveyer pipe 2, the air compressor machine is arranged in injecting into gas to a plurality of tuber pipes to make the buggy conveyer pipe 2 form the wind wall. And an air volume control mechanism 5 for controlling the air volume of the air duct 3 is arranged in the air duct 3, namely, the air volume of air injected into the air ducts by the air compressor is controlled, so that air walls with different strengths are formed. The coal mill body 1 is provided with a plurality of coal outlets, and the coal powder conveying pipes 2 are respectively communicated with the coal outlets. The control system is respectively and electrically connected with a plurality of air volume control mechanisms 5 in the air pipes 3.

Wherein, this application is through control system control amount of wind control machine mechanism, make the amount of wind and the wind speed that air pipe 3 got into buggy conveyer pipe 2 of air control mechanism 5 control, thereby intervene the flow field in buggy conveyer pipe 2, realize the control and get into the purpose of the buggy volume of buggy conveyer pipe 2 and the buggy concentration of adjusting in buggy conveyer pipe 2 by coal pulverizer body 1, make the user can keep basic unanimity with the buggy concentration and the buggy volume of making coal pulverizer body 1 carry to each buggy conveyer pipe 2 through adjusting amount of wind control mechanism 5.

The larger the wind speed of the wind pipe 3 entering the pulverized coal conveying pipe 2 is, the larger the resistance in the pulverized coal conveying pipe 2 is, and the slower the pulverized coal conveying speed is.

Further, referring to fig. 2, an adjustable shrinkage cavity 4 is arranged at an outlet of the pulverized coal conveying pipe 2, and the opening of the adjustable shrinkage cavity 4 is adjusted by a control system, so that the wind speed and wind volume of the pulverized coal conveying pipe 2 are controlled. The adjustable shrinkage cavity 4 and the air volume control mechanism 5 are arranged simultaneously, so that the precision of the control pulverized coal conveying pipe 2 is higher and the flexibility is better.

Further, referring to fig. 1 and 5, the present application further includes: and a coal powder concentration measuring device 8. The coal powder concentration measuring device 8 is used for measuring the coal powder concentration in the coal powder conveying pipe 2. The control system is used for controlling the air volume control mechanism 5 according to the concentration of the pulverized coal, thereby controlling the air pipe to enter the pulverized coal conveying pipe 2. The number of the coal dust concentration measuring devices 8 is multiple, and the coal dust concentration measuring devices 8 are arranged in one-to-one correspondence with the coal dust conveying pipes 2, namely, one coal dust concentration measuring device 8 is arranged in each coal dust conveying pipe 2.

Further, the pulverized coal concentration measuring device 8 includes: a pulverized coal sampling pipe 81, a gas-solid separator 82, a solid weighing device 83, a first control valve 84, a flow meter 85 and an air pump 86; the gas-solid separator 82 has a feed inlet, a gas outlet, and a solids outlet.

The input end of the coal powder sampling pipe 81 is communicated with the coal powder conveying pipe 2, and the output end of the coal powder sampling pipe 81 is communicated with the raw material inlet of the gas-solid separator 82. The solids weighing device 83 is disposed below the solids outlet; the flow meter 85 is communicated with a gas outlet of the solid weighing device 83 through a first pipeline; the first control valve 84 is disposed on the first pipe; the flow meter 85 communicates with the suction pump 86 through a second pipe.

Wherein, the gas-solid separator 82 is a conventional gas-solid separation device in the field of pulverized coal detection, such as: the cyclone separator will be described below by taking a cyclone separator as an example.

When the coal powder concentration online measuring device measures the coal powder concentration online, the air pump 86 works to ensure that the air-powder mixture sample extracted from the coal powder conveying pipe 2 by the coal powder sampling pipe 81 is consistent with the flowing speed of the air-powder mixture in the coal powder conveying pipe 2. The wind-powder mixture sample enters the cyclone separator through the raw material inlet, the solid coal powder is separated from the air flow by the centrifugal force generated when the coal powder rotates at a high speed and can be collected at the solid outlet at the bottom of the cyclone separator, the separated solid coal powder falls into the weighing device, the mass of the solid coal powder in a period of time is calculated, the gas corresponding to the wind-powder mixture sample flows to the flowmeter 85 through the first control valve 84, and the volume of the gas in the wind-powder mixture sample extracted in the corresponding period of time is measured. Wherein the opening degree of the first control valve 84 is operated by the pulverized coal concentration control system.

Wherein, the coal powder concentration is shown; volume of the wind-powder mixture, m 3; m3, which is the volume of the wind-powder mixture corresponding to the solid coal powder; m3, the volume of the wind-powder mixture corresponds to the volume of the gas; the mass of the wind-powder mixture sample corresponding to the mass of the solid coal powder is kg; the density of the solid coal powder is kg/m3 corresponding to the sample of the air-powder mixture.

Two embodiments of the air volume control mechanism 5 will be explained below.

In one embodiment, referring to fig. 4, the air volume control mechanism 5 comprises: a motor 51, a first pivot 52, and a first shutter 53. The first baffle 53 is pivoted in the air duct 3 by a first pivot 52. An output shaft of the motor 51 is coaxially connected with the first pivot 52, the motor 51 is electrically connected with the control system, the rotation of the motor 51 is controlled by the control system, so that the first baffle 53 rotates in the air duct 3, and the rotation of the first baffle 53 can change the size of an air inlet channel in the air duct 3.

In another embodiment, referring to fig. 6, the air volume control mechanism 5 includes: a second control valve 54; the air compressor is respectively connected with a plurality of input ports of the air pipes 3. The second control valve 54 is arranged on the air duct 3.

In order to adjust the concentration of the pulverized coal on line, a method based on flow field intervention is adopted. When the air volume control mechanism 5 adjusts the concentration of the pulverized coal, compressed air with high speed is pumped into the pulverized coal conveying pipe 2 through the air pipe 3, and the high-speed compressed air forms an air wall in the pulverized coal conveying pipe 2 to block the further conveying of the pulverized coal entering from the outlet of the coal mill, so that the amount of the pulverized coal entering the corresponding pulverized coal conveying pipe 2 is controlled, and the pulverized coal concentration adjusting effect is achieved.

The control system is connected with the pulverized coal concentration measuring device 8 and the air volume control mechanism 5. The control system generates an adjusting instruction by judging whether the measured value of the coal powder concentration obtained by on-line measurement is within a target threshold value range, adjusts the air volume and the air speed of compressed air flowing through the air pipe by controlling the second control valve 54, judges whether the optimized coal powder concentration is within the target threshold value range according to the feedback value of the coal powder concentration measurement, and determines whether to further adjust, thereby controlling the coal powder concentration.

Specifically, the cross section of the air duct 3 is circular, and the first baffle 53 is a circular baffle, so that the air duct 3 can be completely shielded by the baffle.

Further, the pulverized coal conveying pipes 2 are straight circular pipes, and the pulverized coal conveying pipes 2 are parallel.

In one possible embodiment, the present application further includes: a fan. The fans are communicated with the air pipes 3, namely a plurality of fans are communicated with the air pipes 3, the air output of the fans is consistent, and the fans are respectively and electrically connected with the control system.

In a possible embodiment, referring to fig. 1 and 3, the present application further comprises: a second shutter 6 and a second pivot 7. The coal dust conveying pipes 2 are divided into a first part coal dust conveying pipe 2 and a second part coal dust conveying pipe 2 which are arranged on two opposite sides of a preset plane. Specifically, the first partial pulverized coal conveying pipe 2 and the second partial pulverized coal conveying pipe 2 are symmetrical with respect to a preset plane.

The second baffle 6 is pivoted in the coal mill body 1 through the second pivot 7; the axis of the second pivot 7 is located in the predetermined plane. A plurality of through holes 61 for coal powder to pass through are formed in the second baffle 6; the second shutter 6 has a first state and a second state.

Under the condition that the second baffle 6 is in the first state, the second baffle 6 is positioned in a first conveying passage of the coal mill body 1 for conveying coal dust to the first part of coal dust conveying pipe 2.

Under the condition that the second baffle 6 is in the second state, the second baffle 6 is positioned in a second conveying passage of the coal mill body 1 for conveying the coal dust to the second part coal dust conveying pipe 2.

Because coal pulverizer body 1, when arranging the environment relatively poor at the powder discharge machine position and other equipment sites of coal fired power plant, the buggy in the coal pulverizer body 1 is carried unevenly especially seriously, it will be relatively poor to adopt tuber pipe 3 and adjustable shrinkage cavity 4's regulation effect, consequently this application passes through the swing of second baffle 6 around second pivot 7, can make the approximate trend of buggy in the control coal pulverizer body 1, the buggy can be partial to one side that is not backstopd by second baffle 6, the buggy in the one side of backstop by second baffle 6 can only pass the through-hole 61 flow direction first part buggy conveyer pipe 2 or the second part buggy conveyer pipe 2 of second baffle 6. When the setting of second baffle 6 can effectively make the buggy seriously be partial to one side, it is more even to make the milling machine carry the buggy to first part buggy conveyer pipe 2 and second part buggy conveyer pipe 2 through second baffle 6.

The second baffle 6 changes the general trend of the pulverized coal in the pulverizer, and the air pipe 3 and the adjustable shrinkage cavity 4 finely adjust the concentration and the amount of the pulverized coal in the pulverized coal conveying pipe 2.

Furthermore, the second baffle 6 is a wear-resistant lining plate, so that the service life of the second baffle 6 is longer, and meanwhile, the wear-resistant lining plate is in contact with pulverized coal to enable the pulverized coal to be finer and finer.

Further, when the coal mill body 1, the powder discharging machine and other equipment of the coal-fired power plant are in poor site arrangement environment, the flow direction of the pulverized coal accounts for about 3: 7, the surface value of the through hole 61 accounts for 70% of the area of the second baffle 6, so that the coal dust in the first part of the coal dust conveying pipe 2 and the second part of the coal dust conveying pipe 2 can be more uniform as much as possible.

To sum up, the embodiment of the utility model provides a coal pulverizer, it passes through control system control amount of wind control machine mechanism, make 5 control tuber pipes of air quantity control mechanism 3 get into buggy conveyer pipe 2's amount of wind and wind speed, thereby intervene the flow field in the buggy conveyer pipe 2, the realization control is by coal pulverizer body 1 get into buggy volume of buggy conveyer pipe 2 and the purpose of adjusting the buggy concentration in buggy conveyer pipe 2, make coal pulverizer body 1 carry the buggy to each buggy conveyer pipe 2 in.

The foregoing is only a preferred embodiment of the present invention, and it should be noted that, for those skilled in the art, a plurality of modifications and replacements can be made without departing from the technical principle of the present invention, and these modifications and replacements should also be regarded as the protection scope of the present invention.

Claims

1. A coal pulverizer, comprising: the coal pulverizer comprises an air compressor, a coal pulverizer body, a coal powder conveying pipe and an air pipe for conveying air into the coal powder conveying pipe; the input port of the air pipe is communicated with the air compressor, and the output port of the air pipe is communicated with the pulverized coal conveying pipe; an air quantity control mechanism for controlling the air quantity of the air pipe is arranged in the air pipe; the number of the air pipes is multiple; the number of the coal dust conveying pipes is multiple; the coal mill body is provided with a plurality of coal outlets; the plurality of air pipes, the plurality of coal powder conveying pipes and the plurality of coal mill bodies are arranged in a one-to-one correspondence manner; each coal dust conveying pipe is communicated with one coal outlet.

2. The coal pulverizer of claim 1, further comprising: the pulverized coal concentration measuring device is used for measuring the concentration of pulverized coal in the pulverized coal conveying pipe, and the control system is used for controlling the air volume control mechanism according to the concentration of the pulverized coal; the number of the pulverized coal concentration measuring devices is multiple; the plurality of coal dust concentration measuring devices are arranged in one-to-one correspondence with the plurality of coal dust conveying pipes.

3. The coal pulverizer of claim 2, wherein the pulverized coal concentration measuring device comprises: the device comprises a pulverized coal sampling pipe, a gas-solid separator, a solid weighing device, a first control valve, a flowmeter and an air pump; the gas-solid separator is provided with a raw material inlet, a gas outlet and a solid outlet;

4. The coal pulverizer of claim 1, wherein the air volume control mechanism comprises: a second control valve; the air compressor is respectively communicated with the input ports of the air pipes; the second control valve is arranged on the air pipe.

5. The coal pulverizer of claim 2, wherein the air volume control mechanism comprises: a motor, a first pivot, and a first baffle; the first baffle is pivoted in the air pipe through a first pivot; an output shaft of the motor is coaxially connected with the first pivot; the motor is electrically connected with the control system.

6. The coal pulverizer of claim 2, further comprising: a second baffle and a second pivot; the coal dust conveying pipes are divided into a first part coal dust conveying pipe and a second part coal dust conveying pipe which are arranged on two opposite sides of a preset plane;

and under the condition that the second baffle is in the second state, the second baffle is positioned in a second conveying passage for conveying the coal powder to the second part of the coal powder conveying pipe by the coal mill body.

7. The coal pulverizer of claim 6, wherein the second baffle is a wear liner.

8. The coal pulverizer of claim 7, wherein the area of the through-holes is 70% of the area of the second baffle.