Air pulverized coal pipeline gridding sampling and layout system for on-line optical detection

Abstract

The utility model discloses a gridding sampling and layout system for an air pulverized coal pipeline for on-line optical detection, and belongs to the technical field of on-line optical detection of air pulverized coal. The utility model solves the problems of low sampling speed, limited installation position and easy influence on the structural reliability of a detection probe in the existing wind powder pipe online sampling device suitable for the optical detection technology. The sampling and discharging main body comprises a shell and a filter fixedly arranged in the shell, a transparent window is arranged at the bottom of the shell, the filter is connected with a suction inlet of the negative pressure power source through a suction pipe, and the shell is connected with the suction inlet of the negative pressure power source through a suction pipe; the other end of the sampling main pipe is connected with a plurality of sampling branch pipes, and one end of the sample discharging pipe is communicated with a discharging opening of the negative pressure power source.

Description

Technical Field

[0001] This utility model relates to a grid-based sampling system for coal dust pipelines used in online optical inspection, belonging to the field of online optical inspection technology for coal dust. Background Technology

[0002] The quality of coal fed into the boiler is crucial for energy conservation and emission reduction in power plants, and to a certain extent determines the overall operating characteristics of coal-fired boilers and even coal-fired power plants. Currently, there is an urgent need for real-time monitoring of coal quality information fed into the boiler.

[0003] Studies have shown that Raman spectroscopy is exceptionally sensitive to structural changes in carbon-containing macromolecular mixtures, and its Raman spectra are simple and easy to interpret. The detection process offers the following advantages: it is non-contact and non-destructive to the sample, allowing for remote measurement; no special sample preparation is required; it is suitable for black and water-containing samples; the instrument is robust, compact, easy to use, and has low maintenance costs; and it can determine the elemental content of coal while also reflecting the combination of elements. These characteristics make Raman spectroscopy a promising potential technology for online coal quality detection.

[0004] To achieve online coal quality detection based on laser Raman spectroscopy, in addition to the fundamental theoretical framework and key mathematical models, it is also necessary to efficiently acquire the Raman spectra of coal in the on-site environment of a coal-fired power plant's coal conveying system. In practical terms, this means constructing an efficient bridge between the online Raman spectroscopy detection equipment and the on-site sample source: an online sampling and discharging device.

[0005] Patent application number 202210091399 discloses an online sampling device and method for air-powder pipes suitable for optical detection technology. It utilizes the positive pressure of the air-powder pipe and the gravity of the powder to directly sample the powder. However, this sampling structure and method have the following problems:

[0006] 1. The achievable sampling speed depends on the combined effect of the working conditions inside the air-powder pipeline and gravity. For example, if the flow velocity inside the pipeline is high and the powder particles are small, the powder will not easily sink, resulting in slow sampling speed or difficulty in sampling.

[0007] 2. The sampling probe needs to be installed below the coal pulverizer pipeline, and the distance from the pipeline should not be too far, otherwise relying solely on gravity will lead to an excessively long sampling cycle.

[0008] 3. Due to limitations in installation location and distance, and the considerable distance between the various coal pulverized air pipelines to be tested in the actual field, one scanning probe can only be used with one sampling device at close range (probe focal length of about 20mm). However, in actual field, multiple coal pulverized air pipelines generally need to be tested, which requires each pipeline to be equipped with a corresponding sampling device and scanning probe. The overall system is complex, costly, requires a large amount of maintenance, and has reduced overall reliability.

[0009] 4. Because the detection probe is close to the pulverized coal pipeline, the high-speed gas-solid two-phase flow inside the pulverized coal pipeline is generally 10-30 m / s. The pipeline vibration caused by the flow will affect the structural reliability of the sampling device and the scanning probe itself, and at the same time have an adverse effect on the optical detection of the scanning probe.

[0010] 5. Existing sampling structures cannot achieve long-distance sampling and discharging. Furthermore, due to the complex pipeline layout of power plants, the on-site placement of sampling and discharging devices and scanning probes is limited, leading to numerous inconveniences in construction and maintenance. Summary of the Invention

[0011] The present invention aims to solve the above-mentioned technical problems and provides a grid-based sampling system for coal dust pipelines for online optical inspection.

[0012] The technical solution adopted by this utility model to solve the above-mentioned technical problems is as follows:

[0013] A gridded sampling and discharge system for pulverized coal pipelines for online optical inspection includes a sampling and discharge main body, a negative pressure power source, a sampling main pipe, a discharge pipe, and a purge pipe. The sampling and discharge main body includes a shell and a filter fixed inside the shell. A transparent window is provided at the bottom of the shell. The filter is connected to the inlet of the negative pressure power source, and the shell is connected to the inlet of the negative pressure power source, respectively, through suction pipes. One end of the sampling main pipe is connected to the shell, and the other end of the sampling main pipe is connected to multiple sampling branch pipes. One end of the discharge pipe is connected to the outlet of the negative pressure power source. The ends of the sampling branch pipes away from the sampling main pipe and the other ends of the discharge pipe are respectively connected to the pulverized coal pipeline. The outlet end of the purge pipe is connected to the bottom of the shell.

[0014] Furthermore, the air inlet of the purge tube is connected to the sampling main tube.

[0015] Furthermore, the negative pressure power source is a pneumatic conveyor, a vacuum generator, an ejector, a fan, or an air pump.

[0016] Furthermore, a first controlled valve is installed on the sampling main pipe.

[0017] Furthermore, each suction tube is equipped with a second controlled valve.

[0018] Furthermore, a third controlled valve is installed on the purge pipe.

[0019] Furthermore, a fourth controlled valve is installed on each sampling branch.

[0020] Furthermore, each sampling branch pipe and each discharge pipe is equipped with a shut-off valve.

[0021] Furthermore, a base is fixed to the bottom of the housing, and an air intake channel is provided on the base. The two ends of the air intake channel are respectively connected to the air outlet of the purge pipe and the inside of the housing.

[0022] Furthermore, the lower part of the shell has a funnel-shaped structure.

[0023] Compared with the prior art, the present invention has the following advantages:

[0024] In this invention, a negative pressure power source is used as an external power source to generate negative pressure suction sampling. Compared with the existing sampling methods, the sampling speed is faster and the controllability is better. Furthermore, due to the setting of external power and multiple sampling branch pipes, it is possible to switch and detect multiple air-coal powder pipelines through a single sampling and discharge main body and detection probe.

[0025] In this utility model, by setting up a sampling main pipe and a sampling branch pipe, sampling can be connected at any position on the side of the air-coal powder pipeline.

[0026] In this invention, the sampling main pipe, sampling branch pipe and sampling discharge pipe are connected to the air-coal powder pipeline in the form of long pipes. Compared with the existing sampling device that is directly connected to the air-coal powder pipeline, this effectively reduces the impact of vibration on the sampling and discharge body and the scanning probe.

[0027] In this invention, because the pulverized coal pipeline is connected via a pipe, the sampling and sampling body and the detection probe do not need to be installed close to the bottom of the pulverized coal pipeline. They can be installed in an open location further away from the pulverized coal pipeline, making construction and maintenance more convenient. Attached Figure Description

[0028] Figure 1 This is a structural diagram of specific implementation method one;

[0029] Figure 2 This is a schematic diagram showing the positional relationship between the grid-based sampling system for online optical inspection of coal dust pipelines and the inspection probe in Specific Implementation Method 1.

[0030] Figure 3 This is a schematic diagram showing the positional relationship between the grid-based sampling system for pulverized coal pipelines used for online optical inspection and the inspection probe in Specific Implementation Method 2.

[0031] In the picture:

[0032] 1. Sampling and discharge main body; 1-1. Shell; 1-2. Filter; 1-3. Transparent window; 1-4. Base; 2. Negative pressure power source; 3. Main sampling pipe; 4. Discharge pipe; 5. Purge pipe; 6. Sampling branch pipe; 7. First suction pipe; 8. Second suction pipe; 9. First controlled valve; 10. Second controlled valve; 11. Third controlled valve; 12. Fourth controlled valve; 13. Shut-off valve; 100. Detection probe. Detailed Implementation

[0033] Combination Figures 1-3 The present invention will be described in further detail below. It should be understood that the specific embodiments described herein are merely illustrative of the invention and not intended to limit it. Furthermore, it should be noted that, for ease of description, the accompanying drawings show only the parts relevant to the invention, not the entire structure.

[0034] In the description of this utility model, unless otherwise explicitly specified and limited, the terms "connected," "linked," and "fixed" should be interpreted broadly. For example, they can refer to a fixed connection, a detachable connection, or an integral part; they can refer to a mechanical connection or an electrical connection; they can refer to a direct connection or an indirect connection through an intermediate medium; they can refer to the internal communication of two components or the interaction between two components. Those skilled in the art can understand the specific meaning of the above terms in this utility model according to the specific circumstances.

[0035] In this invention, unless otherwise explicitly specified and limited, "above" or "below" the second feature can include direct contact between the first and second features, or contact between the first and second features through another feature between them. Furthermore, "above," "over," and "on top" of the second feature includes the first feature directly above or diagonally above the second feature, or simply indicates that the first feature is at a higher horizontal level than the second feature. "Below," "below," and "under" the second feature includes the first feature directly below or diagonally below the second feature, or simply indicates that the first feature is at a lower horizontal level than the second feature.

[0036] In the description of this embodiment, terms such as "upper," "lower," "left," and "right" are based on the orientation or positional relationship shown in the accompanying drawings. They are used only for the convenience of description and simplification of operation, and do not indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation. Therefore, they should not be construed as limitations on this utility model.

[0037] Specific implementation method one: Combining Figures 1-2This embodiment describes a gridded sampling and discharge system for pulverized coal pipelines used in online optical inspection. It includes a sampling and discharge main body 1, a negative pressure power source 2, a sampling main pipe 3, a discharge pipe 4, and a purge pipe 5. The sampling and discharge main body 1 includes a housing 1-1 and a filter 1-2 fixed inside the housing 1-1. A transparent window 1-3 is provided at the bottom of the housing 1-1. The filter 1-2 is connected to the inlet of the negative pressure power source 2, and the housing 1-1 is connected to the inlet of the negative pressure power source 2 via suction pipes. One end of the sampling main pipe 3 is connected to the housing 1-1, and the other end of the sampling main pipe 3 is connected to multiple sampling branch pipes 6. One end of the discharge pipe 4 is connected to the outlet of the negative pressure power source 2. The ends of the sampling branch pipes 6 away from the sampling main pipe 3 and the other end of the discharge pipe 4 are connected to the pulverized coal pipeline. The outlet end of the purge pipe 5 is connected to the bottom of the housing 1-1.

[0038] The detection probe 100 for online optical inspection is positioned directly below the transparent window 1-3 to facilitate online optical inspection.

[0039] The negative pressure power source 2 is a pneumatic conveyor, vacuum generator, jet injector, or air pump.

[0040] The suction pipe between the filter 1-2 and the negative pressure power source 2 is the first suction pipe 7, and the suction pipe between the housing 1-1 and the negative pressure power source 2 is the second suction pipe 8. The first suction pipe 7 and the second suction pipe 8 are connected in parallel.

[0041] By connecting the filter 1-2 in the sampling body 1 to the negative pressure power source 2, during the online optical detection process, the negative pressure power source 2 is activated, and a negative pressure is generated inside the shell 1-1. The air-coal dust is drawn into the shell 1-1 through the sampling main pipe 3. Through the action of the filter 1-2, a negative pressure condition is formed inside the shell 1-1, while most of the air-coal dust is trapped inside the shell 1-1. A small portion of the air-coal dust that is not trapped is sent back to the air-coal dust pipeline through the discharge pipe 4, thus realizing the sampling of the sampling body 1.

[0042] By connecting the housing 1-1 in the sampling and discharging body 1 to the negative pressure power source 2, when it is necessary to purge the inside of the housing 1-1, the valve on the outlet pipe of the filter 1-2 is closed. After the air and coal dust inside the housing 1-1 are purged, they are sucked out by the negative pressure power source 2 and discharged into the air and coal dust pipeline, thus realizing the discharge of the sampling and discharging body 1.

[0043] In this invention, negative pressure sampling is generated by using negative pressure power source 2 as external power. Compared with existing sampling methods, the sampling speed is faster and the controllability is better. Furthermore, due to the setting of external power and multiple sampling branch pipes 6, it is possible to switch and detect multiple air-coal powder pipelines through one set of sampling and discharge main body 1 and detection probe 100.

[0044] In this utility model, by setting up a sampling main pipe 3 and a sampling branch pipe 6, sampling can be connected at any position on the side of the coal pulverizer pipe, realizing grid-based sampling and discharge.

[0045] In this utility model, the sampling main pipe 3, sampling branch pipe 6 and sampling discharge pipe 4 are connected to the air-coal powder pipeline in the form of long pipes. Compared with the existing sampling device that is directly connected to the air-coal powder pipeline, the impact of vibration on the sampling and discharge body 1 and the scanning probe is effectively reduced.

[0046] In this utility model, since the air-coal powder pipeline is connected through a pipe, the sampling body 1 and the detection probe 100 do not need to be installed close to the bottom of the air-coal powder pipeline. They can choose an open location that is farther away from the air-coal powder pipeline to carry out the work, making construction and maintenance more convenient.

[0047] The negative pressure power source 2 is a pneumatic conveyor, vacuum generator, ejector, fan, or air pump. With this design, when the resistance of the external sampling pipeline (including the main sampling pipe 3 and the branch sampling pipe 6) and the discharge pipe 4 is low (e.g., relatively short pipeline, low coefficient of friction on the inner wall of the pipe, few pipe fittings, or few bends in the pipeline), a compressed air-driven power source such as a pneumatic conveyor, vacuum generator, or ejector can be used instead of a power pump, resulting in a simpler structure and more reliable operation. When it is necessary to control the proportion of gas mixed in the pulverized coal pipeline, compressed air can also be mixed into the pulverized coal pipeline through the compressed air-driven power source.

[0048] The sampling main pipe 3 is equipped with a first controlled valve 9.

[0049] Each suction tube is equipped with a second controlled valve 10.

[0050] A third controlled valve 11 is installed on the purge pipe 5.

[0051] Each sampling branch pipe 6 is equipped with a fourth controlled valve 12.

[0052] Each sampling branch pipe 6 and the discharge pipe 4 is equipped with a shut-off valve 13. With this design, the shut-off valve 13 on the sampling branch pipe 6 is located between the fourth controlled valve 12 and the air-coal pulverized oil pipeline.

[0053] A base 1-4 is fixed to the bottom of the housing 1-1, and an air inlet channel is provided on the base 1-4. The two ends of the air inlet channel are respectively connected to the air outlet of the purge pipe 5 and the interior of the housing 1-1. With this design, the air inlet channel on the base 1-4 connects the purge pipe 5 with the interior space of the housing 1-1 above the transparent window 1-3, realizing the purging of the transparent window 1-3 and the interior space of the housing 1-1 above the transparent window 1-3. This facilitates the detection of coal dust at different locations in the coal dust pipeline. Before the next sampling, the interior of the housing 1-1 is purged to ensure that the coal dust to be detected on the transparent window 1-3 is only the coal dust sampled at the current sampling location, effectively improving the accuracy of the detection results.

[0054] The lower part of the shell 1-1 has a funnel-shaped structure. This design facilitates the falling coal dust onto the transparent window 1-3.

[0055] Specific Implementation Method Two: Combining Figure 3 In this embodiment, the air inlet of the purge pipe 5 is connected to the sampling main pipe 3. With this design, when the negative pressure power source 2 is an air pump, the air-coal powder deposited on the transparent viewing windows 1-3 is purged by extracting a gas-solid two-phase flow (dilute phase) sample, thereby achieving a complete closed loop between the sampling system and the air-coal powder pipeline. This means that no external gas enters the air-coal powder pipeline during system operation, minimizing the impact on the original air-coal powder system. The connection interface between the purge pipe 5 and the sampling main pipe 3 can be located at any position on the cross-section of the sampling main pipe 3. Other components and connections are the same as in specific embodiment one.

Claims

1. A grid-based sampling system for pulverized coal pipelines used in online optical inspection, characterized in that: The system includes a sampling and discharge body (1), a negative pressure power source (2), a sampling main pipe (3), a discharge pipe (4), and a purge pipe (5). The sampling and discharge body (1) includes a shell (1-1) and a filter (1-2) fixed inside the shell (1-1). A transparent window (1-3) is provided at the bottom of the shell (1-1). The filter (1-2) is connected to the suction port of the negative pressure power source (2) and the shell (1-1) is connected to the suction port of the negative pressure power source (2) through suction pipes. One end of the sampling main pipe (3) is connected to the shell (1-1), and the other end of the sampling main pipe (3) is connected to multiple sampling branch pipes (6). One end of the discharge pipe (4) is connected to the discharge port of the negative pressure power source (2). The end of the sampling branch pipe (6) away from the sampling main pipe (3) and the other end of the discharge pipe (4) are connected to the air-coal powder pipeline, respectively. The air outlet of the purge pipe (5) is connected to the bottom of the shell (1-1).

2. The grid-based sampling system for pulverized coal pipelines for online optical inspection according to claim 1, characterized in that: The air inlet of the purge tube (5) is connected to the sampling tube (3).

3. A grid-based sampling system for pulverized coal pipelines for online optical inspection according to claim 1 or 2, characterized in that: The negative pressure power source (2) is a pneumatic conveyor, vacuum generator, jet injector, fan or air pump.

4. A grid-based sampling system for pulverized coal pipelines for online optical inspection according to claim 1 or 2, characterized in that: The sampling main pipe (3) is equipped with a first controlled valve (9).

5. A grid-based sampling system for pulverized coal pipelines for online optical inspection according to claim 1 or 2, characterized in that: Each suction tube is equipped with a second controlled valve (10).

6. A grid-based sampling system for pulverized coal pipelines for online optical inspection according to claim 1 or 2, characterized in that: A third controlled valve (11) is installed on the purge pipe (5).

7. A grid-based sampling system for pulverized coal pipelines for online optical inspection according to claim 1 or 2, characterized in that: Each sampling branch (6) is equipped with a fourth controlled valve (12).

8. A grid-based sampling system for pulverized coal pipelines for online optical inspection according to claim 1 or 2, characterized in that: Each sampling branch (6) and each discharge branch (4) is equipped with a shut-off valve (13).

9. A grid-based sampling system for pulverized coal pipelines for online optical inspection according to claim 1 or 2, characterized in that: The bottom of the housing (1-1) is fixedly provided with a base (1-4), and an air inlet channel is provided on the base (1-4). The two ends of the air inlet channel are respectively connected to the air outlet of the purge pipe (5) and the inside of the housing (1-1).

10. A grid-based sampling system for pulverized coal pipelines for online optical inspection according to claim 1 or 2, characterized in that: The lower part of the shell (1-1) has a funnel-shaped structure.

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