A real-time detection device for coal powder flow deviation, a pulverizing system and a detection method

Abstract

The present invention relates to a real-time detection device for coal powder flow deviation, a pulverizing system and a detection method. The detection device comprises: a coal powder collection pipe, which comprises a vertical transparent section and a U-shaped section. The vertical transparent section is fixed below a horizontal coal powder pipeline through a pipe seat and is connected to the inside of the horizontal coal powder pipeline; a light-controlled switch is installed on the vertical transparent section; the U-shaped section is connected to a horizontal section in the horizontal direction, and a solenoid valve is installed on the horizontal section; the horizontal section is bent downward and extends to have a backflush section connected to a compressed air source; the light-controlled switch and the solenoid valve are both electrically connected to an industrial control machine. The present invention directly measures the volume of sampled coal powder, and the measurement result is more accurate than indirect measurement methods such as charge method or microwave method. The industrial control machine respectively counts the number of triggers per unit time or the sum of the number of triggers of one or more light-controlled switches on each coal powder pipe, and judges the deviation of coal powder flow between coal powder pipes by comparing the sum of the number of triggers per unit time between different coal powder pipes.

Description

Technical Field

[0001] The present invention relates to the technical field of pulverized coal control, and more particularly to a pulverized coal flow deviation real-time detection device, a pulverizing system and a detection method. Background Art

[0002] The pulverizing system consists of a coal mill and several coal powder pipelines connected to it. The coal mill grinds the raw coal into coal powder of qualified fineness and transports it to the boiler for combustion through the coal powder pipeline. In order to improve the combustion efficiency of the boiler and the safety of boiler operation, the coal powder fineness, coal powder concentration and coal powder flow rate in each coal powder pipeline are required to be as consistent as possible. Boiler coking, pipe burst, uneven temperature field, high carbon content in fly ash, and large NOx generation are all directly related to coal powder deviation. Controlling coal powder deviation in the pipeline is crucial to improving the economy and safety of boiler operation.

[0003] However, a large amount of measured data shows that the coal flow deviation in the coal pipeline is very large, and it is common for the deviation to reach more than ±30%, and some even exceed ±50%. Moreover, this deviation is not constant. When factors such as coal mill output and coal quality change, the magnitude of the deviation also changes. If the coal deviation is to be controlled, it is necessary to be able to detect the deviation in real time. The methods currently used are all indirect measurement methods, such as charge method, microwave method, laser method, etc. Although these methods can achieve real-time measurement, the accuracy and reliability of the measurement are very poor, which limits the implementation of coal deviation control.

[0004] Therefore, how to provide a reliable real-time detection system for coal powder flow deviation is an urgent problem to be solved by those skilled in the art. Summary of the invention

[0005] To this end, an object of the present invention is to provide a real-time detection device for coal powder flow deviation to solve the problems of inaccurate detection and poor reliability of indirect measurement methods in the prior art.

[0006] The present invention provides a real-time detection device for coal powder flow deviation, comprising:

[0007] A pulverized coal collection pipe, the pulverized coal collection pipe comprises a vertical transparent section and a U-shaped section, the vertical transparent section is fixed below the horizontal pulverized coal pipeline through a pipe seat and is connected to the inside of the horizontal pulverized coal pipeline;

[0008] A light-operated switch is installed on the vertical transparent section;

[0009] The solenoid valve, the U-shaped section is connected to a horizontal section in the horizontal direction, and the solenoid valve is installed on the horizontal section; the horizontal section is bent downward and extended to form a back-blowing section connected to a compressed air source;

[0010] Among them, the light-controlled switch and the solenoid valve are both electrically connected to the industrial control machine.

[0011] Through the above technical scheme, it can be known that compared with the prior art, the present invention discloses a real-time detection device for coal powder flow deviation, which is connected to a coal powder collection pipe below a horizontal coal powder pipeline, and uses the characteristic that the deposition speed of coal powder in the coal powder collection pipe is positively correlated with the concentration of coal powder in the coal powder pipeline (coal powder flow rate) to detect the deposition status of coal powder in the coal powder collection pipe. When the coal powder is deposited to a certain height, it blocks the light of the light-controlled switch to trigger the light-controlled switch. The industrial computer receives the light-controlled switch signal, controls the solenoid valve to turn on, and uses compressed air to back-blow the coal powder collection pipe to blow the coal powder in the coal powder collection pipe back into the coal powder pipeline. Then, the solenoid valve is closed, and the coal powder collection pipe collects the coal powder again. The industrial computer determines the coal powder flow deviation between the coal powder pipes by counting the number of triggering times of the light-controlled switch on each coal powder pipeline in a unit time. Therefore, the present invention solves the problem of inaccurate detection of coal powder flow deviation in the coal powder pipeline and poor reliability, provides necessary conditions for the next step of air-powder control in the coal powder pipeline, and is of great significance to improving the combustion efficiency of the boiler and the safety of the boiler operation.

[0012] Furthermore, the vertical transparent section is made of transparent material. A transparent quartz tube can be used. Quartz has high hardness and can withstand the wear and tear during coal powder backblowing. Obviously, other materials that meet the requirements of transparency and wear resistance are also acceptable.

[0013] Furthermore, the pipe seat, the U-shaped section, the horizontal section and the back-blowing section are all made of steel.

[0014] Furthermore, a right-angle elbow is provided between the U-shaped section and the horizontal section, and the right-angle elbow can be made of steel. The U-shaped section uses the structure of the U-shaped tube to make the coal powder form a self-sealing state at the bottom of the U-shaped tube, thereby preventing the coal powder from contacting the electromagnetic valve and protecting the electromagnetic valve.

[0015] Another object of the present invention is to provide a pulverizing system, including a pulverizing device and the above-mentioned real-time detection device for pulverized coal flow deviation, wherein the vertical transparent section is connected to the bottom of the horizontal pulverized coal pipeline corresponding to each pulverized coal pipeline through a pipe seat, and is connected to the inside of the horizontal pulverized coal pipeline. It can be seen from the above-mentioned technical solution that compared with the prior art, the present invention discloses a pulverizing system, which provides necessary conditions for air-powder control in the pulverized coal pipeline by accurately detecting the pulverized coal flow deviation in each pulverized coal pipeline, and is of great significance to improving the combustion efficiency of the boiler and the safety of the boiler operation.

[0016] Furthermore, a plurality of groups of real-time detection devices for pulverized coal flow deviation are arranged below the corresponding horizontal pulverized coal pipeline on each pulverized coal pipeline, and the distance between adjacent real-time detection devices for pulverized coal flow deviation is 0.8-1.2 m.

[0017] Since the concentration of pulverized coal in the pulverized coal pipeline is uneven on the cross section of the pipeline, there is a large segregation, and the segregation state is not fixed, but changes in real time with time and position. In order to eliminate the influence of concentration segregation on the pulverized coal deposition rate in the pulverized coal collection pipe, multiple pulverized coal collection pipes are installed along the horizontal pipeline length direction corresponding to the pulverized coal pipeline. The industrial computer counts the number of triggering of the light-controlled switch on each pulverized coal pipeline, and detects the deviation of the pulverized coal flow in the pulverized coal pipeline by comparing the number of triggering of each pulverized coal pipe within a fixed time before the current moment. In this way, the interference caused by the segregation of pulverized coal in the pulverized coal pipeline on the measurement is eliminated.

[0018] The present invention also provides a method for realizing real-time detection of coal powder flow deviation of the above-mentioned pulverizing system, by utilizing the linear positive correlation between coal powder concentration in the coal powder pipeline and coal powder deposition speed in the coal powder collecting pipe, and a light-controlled switch detects the height value of the deposited coal powder in the coal powder collecting pipe. When the deposited coal powder height blocks the light of the light-controlled switch, the light-controlled switch triggers and sends a signal to an industrial computer. The industrial computer counts the triggering times of the corresponding light-controlled switch on each coal powder pipeline within a unit time, and determines the coal powder flow deviation between each coal powder pipeline. After receiving the light-controlled switch signal, the industrial computer controls the solenoid valve to turn on, and uses compressed air to back-blow the coal powder collecting pipe, so as to blow the coal powder deposited in the coal powder collecting pipe back into the horizontal coal powder pipeline, and then closes the solenoid valve, so that the coal powder collecting pipe collects the coal powder again.

[0019] It can be seen from the above technical solution that, compared with the prior art, the present invention discloses a method for real-time detection of coal powder flow deviation in a pulverizing system. The present invention directly measures the volume of sampled coal powder, and the measurement result is more accurate than indirect measurement methods such as charge method or microwave method. The industrial computer counts the number of triggers per unit time (or the sum of the number of triggers) of one or more optical switches on each coal powder pipe, and judges the deviation of coal powder flow between coal powder pipes by comparing the sum of the number of triggers per unit time between different coal powder pipes. BRIEF DESCRIPTION OF THE DRAWINGS

[0020] In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the drawings required for use in the embodiments or the description of the prior art will be briefly introduced below. Obviously, the drawings described below are only embodiments of the present invention. For ordinary technicians in this field, other drawings can be obtained based on the provided drawings without paying creative work.

[0021] Figure 1 The accompanying drawing is a schematic structural diagram of a real-time detection device for coal powder flow deviation provided by the present invention;

[0022] Figure 2 The accompanying drawing shows a schematic diagram of the structure of a coal powder collecting pipe;

[0023] In the figure: 100-, 200-coal powder collecting pipe, 201-vertical transparent section, 202-U-shaped section, 203-tube seat, 204-horizontal section, 205-backblowing section, 206-right angle elbow, 300-light-operated switch, 400-solenoid valve, 500-compressed air source. DETAILED DESCRIPTION

[0024] Embodiments of the present invention are described in detail below, examples of which are shown in the accompanying drawings, wherein the same or similar reference numerals throughout represent the same or similar elements or elements having the same or similar functions. The embodiments described below with reference to the accompanying drawings are exemplary and are intended to be used to explain the present invention, and should not be construed as limiting the present invention.

[0025] In the description of the present invention, it is necessary to understand that the terms "up", "down", "front", "back", "left", "right", "vertical", "horizontal", "top", "bottom", "inside", "outside", etc., indicating the orientation or position relationship are based on the orientation or position relationship shown in the drawings, and are only for the convenience of describing the present invention and simplifying the description, rather than indicating or implying that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and therefore cannot be understood as a limitation on the present invention.

[0026] In addition, the terms "first" and "second" are used for descriptive purposes only and should not be understood as indicating or implying relative importance or implicitly indicating the number of the indicated technical features. Therefore, the features defined as "first" and "second" may explicitly or implicitly include one or more of the features. In the description of the present invention, the meaning of "plurality" is two or more, unless otherwise clearly and specifically defined.

[0027] In the present invention, unless otherwise clearly specified and limited, the terms "installed", "connected", "connected", "fixed" and the like should be understood in a broad sense, for example, it can be a fixed connection, a detachable connection, or an integral connection; it can be a mechanical connection or an electrical connection; it can be a direct connection or an indirect connection through an intermediate medium, it can be the internal connection of two elements or the interaction relationship between two elements. For ordinary technicians in this field, the specific meanings of the above terms in the present invention can be understood according to specific circumstances.

[0028] In the present invention, unless otherwise clearly specified and limited, a first feature being "above" or "below" a second feature may include that the first and second features are in direct contact, or may include that the first and second features are not in direct contact but are in contact through another feature between them. Moreover, a first feature being "above", "above" and "above" a second feature includes that the first feature is directly above and obliquely above the second feature, or simply indicates that the first feature is higher in level than the second feature. A first feature being "below", "below" and "below" a second feature includes that the first feature is directly below and obliquely below the second feature, or simply indicates that the first feature is lower in level than the second feature.

[0029] See attached Figure 1 and 2 The embodiment of the present invention discloses a real-time detection device for coal powder flow deviation, comprising:

[0030] A pulverized coal collection pipe 200, the pulverized coal collection pipe 200 comprises a vertical transparent section 201 and a U-shaped section 202, the vertical transparent section 201 is fixed below the horizontal pulverized coal pipeline 100 through a pipe seat 203, and is communicated with the interior of the horizontal pulverized coal pipeline 100;

[0031] A light-operated switch 300 is installed on the vertical transparent section 201;

[0032] The solenoid valve 400, the U-shaped section 202 is connected to the horizontal section 204 in the horizontal direction, and the solenoid valve 400 is installed on the horizontal section 204; the horizontal section 204 is bent downward and extended to form a backflush section 205 connected to the compressed air source 500;

[0033] The light-operated switch 300 and the solenoid valve 400 are both electrically connected to the industrial control machine.

[0034] The present invention discloses a real-time detection device for coal powder flow deviation. A coal powder collecting pipe is connected below a horizontal coal powder pipeline. The deposition speed of coal powder in the coal powder collecting pipe is positively correlated with the concentration (coal powder flow) of coal powder in the coal powder collecting pipe. The deposition status of coal powder in the coal powder collecting pipe is detected by using the characteristic that the deposition speed of coal powder in the coal powder collecting pipe is positively correlated with the concentration (coal powder flow) of coal powder in the coal powder collecting pipe. When the coal powder is deposited to a certain height, the light of the light-controlled switch is blocked to trigger the light-controlled switch. The industrial computer receives the light-controlled switch signal, controls the electromagnetic valve to turn on, and uses compressed air to back-blow the coal powder collecting pipe to blow the coal powder in the coal powder collecting pipe back into the coal powder pipeline. Then the electromagnetic valve is closed, and the coal powder collecting pipe collects the coal powder again. The industrial computer determines the coal powder flow deviation between the coal powder pipes by counting the number of triggering times of the light-controlled switch on each coal powder pipeline in a unit time. Therefore, the present invention solves the problem of inaccurate detection of coal powder flow deviation in the coal powder pipeline and poor reliability, provides necessary conditions for the next step of air-powder control in the coal powder pipeline, and is of great significance to improving the combustion efficiency of the boiler and the safety of the boiler operation.

[0035] Advantageously, the vertical transparent section 201 is made of a transparent material. A transparent quartz tube may be used, which has a high hardness and can withstand the wear and tear during the backblowing of coal powder. Obviously, other materials that meet the requirements of transparency and wear resistance are also acceptable.

[0036] More advantageously, the pipe base 203, the U-shaped section 202, the horizontal section 204 and the back-blowing section 205 are all made of steel.

[0037] In the above embodiment, a right-angle elbow 206 is provided between the U-shaped section 202 and the horizontal section 204. The right-angle elbow can be made of steel. The U-shaped section is used to utilize the structure of the U-shaped tube to make the coal powder form a self-sealing state at the bottom of the U-shaped tube, thereby preventing the coal powder from contacting the electromagnetic valve and protecting the electromagnetic valve.

[0038] The present invention also provides a pulverizing system, including a pulverizing device and the above-mentioned pulverized coal flow deviation real-time detection device, wherein the vertical transparent section 201 is connected to the bottom of the horizontal pulverized coal pipeline 100 corresponding to each pulverized coal pipeline through a pipe seat 203, and is connected to the inside of the horizontal pulverized coal pipeline 100.

[0039] The invention discloses a pulverizing system, which provides necessary conditions for air-powder control in the pulverized coal pipelines by accurately detecting the pulverized coal flow deviation in each pulverized coal pipeline, and is of great significance to improving the combustion efficiency of the boiler and the safety of the boiler operation.

[0040] In another embodiment of the pulverizing system provided by the present invention, a plurality of groups of real-time detection devices for pulverized coal flow deviation are arranged below the horizontal pulverized coal pipeline 100 corresponding to each pulverized coal pipeline, and the distance between adjacent real-time detection devices for pulverized coal flow deviation is 0.8-1.2m. Since the concentration of pulverized coal in the pulverized coal pipeline is uneven on the cross section of the pipeline, there is a large segregation, and the segregation state is not fixed, but changes in real time with time and position. In order to eliminate the influence of concentration segregation on the deposition speed of pulverized coal in the pulverized coal collection pipe, multiple pulverized coal collection pipes are installed along the length direction of the horizontal pipeline corresponding to the pulverized coal pipeline, and the industrial control computer counts the number of triggering of the optical switch on each pulverized coal pipeline respectively, and realizes the detection of pulverized coal flow deviation in the pulverized coal pipeline by comparing the number of triggering of each pulverized coal pipe within a fixed time before the current moment. In this way, the interference of pulverized coal segregation in the pulverized coal pipeline on the measurement is eliminated.

[0041] The present invention also provides a method for realizing real-time detection of coal powder flow deviation of the above-mentioned pulverizing system, by utilizing the linear positive correlation between coal powder concentration in the coal powder pipeline and coal powder deposition speed in the coal powder collecting pipe, and a light-controlled switch detects the height value of the deposited coal powder in the coal powder collecting pipe. The height of the deposited coal powder blocks the light of the light-controlled switch, and the light-controlled switch is triggered to send a signal to an industrial computer. The industrial computer counts the triggering times of the corresponding light-controlled switch on each coal powder pipeline per unit time, and determines the coal powder flow deviation between each coal powder pipeline. After receiving the light-controlled switch signal, the industrial computer controls the solenoid valve to turn on, and uses compressed air to back-blow the coal powder collecting pipe, so as to blow the coal powder deposited in the coal powder collecting pipe back into the horizontal coal powder pipeline, and then closes the solenoid valve, and the coal powder collecting pipe collects the coal powder again.

[0042] The present invention discloses a method for real-time detection of coal powder flow deviation in a pulverizing system. The present invention directly measures the volume of sampled coal powder, and the measurement result is more accurate than indirect measurement methods such as charge method or microwave method. An industrial computer counts the number of triggers per unit time (or the sum of the number of triggers) of one or more optical switches on each coal powder pipe, and determines the deviation of the coal powder flow between coal powder pipes by comparing the sum of the number of triggers per unit time between different coal powder pipes.

[0043] In the present invention, the deposition rate of coal powder in the coal powder collecting pipe is positively correlated with the coal powder concentration in the coal powder pipeline, which means that in the coal powder pipeline, the primary wind speed is the same. When an air-powder mixture flows through the coal powder pipeline, a trace amount of coal powder will be deposited in the coal powder collecting pipe, and the deposition rate of coal powder in the collection pipe is positively correlated with the flow rate of coal powder in the coal powder pipeline (coal powder concentration), that is, the greater the coal powder concentration in the pipeline (the greater the flow rate of coal powder), the faster the coal powder deposition rate.

[0044] In order to ensure the accuracy of the measurement, the external boundary conditions of the pulverized coal pipeline should be set consistently, that is, the diameter of the pulverized coal pipeline, the air-powder flow rate in the pipeline, the distance between the measuring section and the previous elbow, etc. should all be consistent, because the deviation of the pulverized coal flow in the pulverized coal pipeline is caused by the deviation of the pulverized coal concentration.

[0045] In the description of this specification, the description with reference to the terms "one embodiment", "some embodiments", "example", "specific example", or "some examples" etc. means that the specific features, structures, materials or characteristics described in conjunction with the embodiment or example are included in at least one embodiment or example of the present invention. In this specification, the schematic representations of the above terms do not necessarily refer to the same embodiment or example. Moreover, the specific features, structures, materials or characteristics described may be combined in any one or more embodiments or examples in a suitable manner. In addition, those skilled in the art may combine and combine different embodiments or examples described in this specification.

[0046] Although the embodiments of the present invention have been shown and described above, it is to be understood that the above embodiments are exemplary and are not to be construed as limitations of the present invention. A person skilled in the art may change, modify, replace and vary the above embodiments within the scope of the present invention.

Claims

1. A flour making system, It is characterized in that It comprises a pulverizing device and a real-time detection device for pulverized coal flow deviation, wherein a plurality of groups of the real-time detection devices for pulverized coal flow deviation are arranged below a horizontal pulverized coal pipeline (100) corresponding to each pulverized coal pipeline in the pulverizing device; wherein each group of the real-time detection devices for pulverized coal flow deviation comprises: A coal powder collection pipe (200), the coal powder collection pipe (200) comprising a vertical transparent section (201) and a U-shaped section (202), the vertical transparent section (201) being connected to the bottom of a horizontal coal powder pipe (100) corresponding to each coal powder pipe through a pipe seat (203) and being in communication with the interior of the horizontal coal powder pipe (100); A light-controlled switch (300), wherein the light-controlled switch (300) is mounted on the vertical transparent section (201); A solenoid valve (400), wherein the U-shaped section (202) is connected to a horizontal section (204) in a horizontal direction, and the solenoid valve (400) is installed on the horizontal section (204); the horizontal section (204) is bent downward and extends to form a backflush section (205) connected to a compressed air source (500); The light-controlled switch (300) and the solenoid valve (400) are both electrically connected to an industrial control computer; the industrial control computer reflects the flow rate of a single coal powder pipeline by counting the number of times each coal powder collection pipe (200) is filled and emptied with coal powder, and compares the number of counts between different coal powder pipelines to determine the deviation of the coal powder flow rate.

2. The flour milling system according to claim 1, It is characterized in that The distance between adjacent coal powder flow deviation real-time detection devices is 0.8-1.2m.

3. The flour milling system according to claim 1, It is characterized in that The vertical transparent section (201) is made of transparent material.

4. The flour milling system according to claim 1, It is characterized in that The pipe seat (203), the U-shaped section (202), the horizontal section (204) and the backflush section (205) are all made of steel.

5. The flour milling system according to claim 1, It is characterized in that A right-angle elbow (206) is provided in transition connection between the U-shaped section (202) and the horizontal section (204).

6. A method for realizing real-time detection of coal powder flow deviation in the pulverizing system according to any one of claims 1 to 5, It is characterized in that Utilizing the linear positive correlation between the concentration of pulverized coal in the pulverized coal pipeline and the deposition speed of pulverized coal in the pulverized coal collecting pipe, the optical switch detects the height of the deposited pulverized coal in the pulverized coal collecting pipe. When the height of the deposited pulverized coal blocks the light of the optical switch, the optical switch is triggered to send a signal to the industrial computer. The industrial computer counts the number of triggering times of the corresponding optical switch on each pulverized coal pipeline per unit time, and determines the pulverized coal flow deviation between the pulverized coal pipelines. After receiving the signal from the optical switch, the industrial computer controls the solenoid valve to turn on, and uses compressed air to back-blow the pulverized coal collecting pipe, so as to blow the pulverized coal deposited in the pulverized coal collecting pipe back into the horizontal pulverized coal pipeline. Then, the solenoid valve is closed, and the pulverized coal collecting pipe collects the pulverized coal again.

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