Device and method for detecting particulate matter in a gas

Abstract

The application provides a device and method for detecting particles in gas, which comprises a sample inlet tube, a sampling unit and a detection unit, the detection unit comprises a radioactive source and a detector, the sampling unit and the detection unit are arranged on a support; further comprising: a first component has a through hole, the receiving end of the detector is in the through hole; the first component has a groove allowing the movement piece to pass through; a second component has a first gas channel and a second gas channel in communication with the sample inlet tube, the second component and the first component are fixedly connected and arranged on the support; a paper tape is on the upper side of the second component; a first driving unit is used to drive the radioactive source to move vertically, so that when the radioactive source presses the paper tape, the gas passes through the sample inlet tube, the first gas channel and the second gas channel in turn, and the radioactive source is on the gas path; a second driving unit is used to drive the movement piece to move back and forth, so that the movement piece blocks the receiving end as needed. The application has the advantages of in-situ analysis, accurate detection and the like.

Description

Technical Field

[0001] This invention relates to particulate matter detection, and particularly to an apparatus and method for detecting particulate matter in gases. Background Technology

[0002] The beta-ray method is a national standard method for particulate matter monitoring. It is designed based on the principle of beta-ray absorption. Beta rays are a high-speed electron stream; high-energy particles emitted from 14C (carbon dioxide) experience energy reduction or absorption when they encounter dust particles. For a given beta-ray intensity, the amount absorbed depends only on the mass of the absorbing material, regardless of its physicochemical properties. When the material is placed between the 14C emission source and the beta-ray device, the absorption of beta rays causes energy attenuation, resulting in a reduction in the number of beta particles detected. The mass of particulate matter collected on the filter paper is calculated based on the change in beta-ray intensity as it passes through clean and particulate-laden filter paper, thus determining the concentration of particulate matter in the air.

[0003] A typical monitoring instrument involves several steps: raising the lever, feeding the paper, lowering the lever to clamp the paper, cleaning and detecting the filter paper, collecting air samples, and detecting when the air supply stops. To ensure accurate and reliable measurements, the position of the filter paper must be perfectly accurate during both measurements. The detectors used in the monitoring instrument are usually either scintillation detectors or Geiger counters. Both types of detectors are highly susceptible to damage at their detection surfaces, with Geiger counters being particularly vulnerable due to a thin layer of natural mica on their surface, which is easily damaged under stress (during air collection). Scintillation detectors are slightly better protected against stress, but damage to the test surface is still common during use, and they are significantly more expensive than Geiger counters.

[0004] To address the issue of stress on the detector, many monitoring instruments employ a reciprocating paper feeding mechanism. Chinese patent CN204008388U proposes a reciprocating paper feeding mechanism. However, since the detector's test point and data acquisition point are not in the same position, the rod needs to be raised and the paper fed multiple times. This makes the entire paper feeding device complex, and it is difficult to ensure that the filter paper position is consistent for two tests using reciprocating paper feeding. Summary of the Invention

[0005] To address the shortcomings of the existing technical solutions, the present invention provides a gas particulate matter detection device.

[0006] The objective of this invention is achieved through the following technical solution:

[0007] A gas particulate matter detection device, comprising a sample inlet tube, a sampling unit, and a detection unit, wherein the sampling unit includes a paper tape, a first wheel, and a second wheel, and the detection unit includes a radiation source and a detector, the sampling unit and the detection unit being mounted on a support; the gas particulate matter detection device further includes:

[0008] A first component has a through-hole, and the receiving end of the detector is located within the through-hole; the first component has a groove that allows a movable part to pass through;

[0009] The second component has a first gas channel and a second gas channel communicating with the injection tube. The second component and the first component are fixedly connected and disposed on the support. The paper tape is located on the upper side of the second component.

[0010] The first driving unit is used to drive the radiation source to move vertically, so that when the radiation source squeezes the paper tape, the gas passes through the sample inlet tube, the first gas channel and the second gas channel in sequence, and the radiation source is in the gas path;

[0011] A movable component and a second driving unit, wherein the second driving unit is used to drive the movable component to move back and forth, so that the movable component blocks the receiving end as needed.

[0012] Another objective of this invention is to provide a method for detecting particulate matter in gas, which is achieved through the following technical solution:

[0013] A method for detecting particulate matter in a gas, comprising the following steps:

[0014] (A1) The first driving unit drives the radiation source to move upward, and the radiation source leaves the paper tape; the blank paper tape moves to the lower side of the radiation source;

[0015] (A2) The first driving unit drives the radiation source to move downward and squeeze the blank paper tape; the second driving unit drives the moving part to move forward and no longer block the receiving end of the detector. The rays emitted by the radiation source pass through the paper tape and the second component in sequence and are received by the receiving end of the detector in the first component to obtain the blank signal of the paper tape.

[0016] (A3) The second driving unit drives the moving part to move in the opposite direction, enters the first component, and blocks the receiving end; the gas passes through the injection tube, paper tape and the second component in sequence, and the particulate matter in the gas is intercepted by the paper tape;

[0017] (A4) The second driving unit drives the moving part to move forward, no longer blocking the receiving end; the rays emitted by the radiation source pass through the particles, the paper tape and the second component in sequence, and are received by the receiving end of the detector to obtain the measurement signal of the particles on the paper tape;

[0018] (A5) Based on the measured signal and the blank signal, the particulate matter content in the gas is obtained.

[0019] Compared with the prior art, the beneficial effects of the present invention are as follows:

[0020] 1. In-situ detection;

[0021] Throughout the entire testing cycle, only one paper feeding action is required. Between two measurements, the filter paper remains in a compressed state. In-situ detection ensures accurate positioning without errors, simplifying the entire paper feeding device, saving costs, and reducing measurement errors.

[0022] 2. Long service life;

[0023] During the air extraction process, the moving part shields the receiver of the detector, preventing the airflow from impacting the receiver, effectively protecting the detector, greatly reducing the probability of damage to the detector, and extending the service life of the entire detection device.

[0024] A first gas channel and a second gas channel are provided in the second component, so that during the evacuation, the gas is discharged from the second component through the second gas channel, preventing the airflow from impacting the detector receiver in the first component and effectively protecting the detector.

[0025] 3. High reliability;

[0026] A first guide and a second guide are respectively set on both sides of the second component. The movement of the paper tape is constrained by the guides to prevent deviation and improve the reliability of operation. Attached Figure Description

[0027] The disclosure of this invention will become more readily understood with reference to the accompanying drawings. It will be readily understood by those skilled in the art that these drawings are merely illustrative of the technical solutions of this invention and are not intended to limit the scope of protection of this invention. In the drawings:

[0028] Figure 1 This is a schematic diagram of the structure of a gas particulate matter detection device according to an embodiment of the present invention;

[0029] Figure 2 This is a partial structural schematic diagram of a gas particulate matter detection device according to an embodiment of the present invention;

[0030] Figure 3 This is a schematic diagram of the structure of the second driving unit according to an embodiment of the present invention;

[0031] Figure 4 This is a schematic diagram of the state of the second driving unit according to an embodiment of the present invention. Detailed Implementation

[0032] Figure 1-4The following description illustrates optional embodiments of the invention to teach those skilled in the art how to implement and reproduce the invention. Some conventional aspects have been simplified or omitted to explain the technical solutions of the invention. Those skilled in the art should understand that variations or substitutions derived from these embodiments will be within the scope of the invention. Those skilled in the art should understand that the following features can be combined in various ways to form multiple variations of the invention. Therefore, the invention is not limited to the following optional embodiments, but is defined only by the claims and their equivalents.

[0033] Example 1:

[0034] Figure 1-2 A schematic diagram of the gas particulate matter detection device according to Embodiment 1 of the present invention is shown, as follows: Figure 1-2 As shown, the gas particulate matter detection device includes:

[0035] The sample tube 8, the sampling unit and the detection unit are provided. The sampling unit includes a paper tape 3, a first wheel 13 and a second wheel 14. The detection unit includes a radiation source 6 and a detector 2. The sampling unit and the detection unit are mounted on a support.

[0036] The first component 4 has a through hole, and the receiving end of the detector 2 is located in the through hole; the first component 4 has a groove that allows the movable member 106 to pass through;

[0037] The second component 5 has a first gas channel and a second gas channel communicating with the sample inlet tube 8. The second component 5 and the first component 4 are fixedly connected and disposed on the support. The paper tape 4 is located on the upper side of the second component 5.

[0038] The first driving unit is used to drive the radiation source 6 to move vertically, so that when the radiation source 6 squeezes the paper tape 3, the gas passes through the sample inlet tube 8, the first gas channel and the second gas channel in sequence, and the radiation source 6 is in the gas path.

[0039] The movable component 106 and the second driving unit are provided. The second driving unit is used to drive the movable component 106 to move back and forth, so that the movable component 106 blocks the receiving end as needed.

[0040] To stably and reliably drive the moving part 106 to move in both the forward and directional directions, further, as... Figure 3-4 As shown, the second driving unit includes:

[0041] The motor and the rotating disk 101 are fixed on the bracket and drive the rotating disk 101 to rotate. The rotating disk 101 is provided with a column 105.

[0042] The slider 102 is disposed on the guide rail 103 and has a limiting groove that allows the column 105 to be inserted. The angle between the extending direction of the limiting groove and the extending direction of the guide rail 103 is a right angle or an acute angle.

[0043] Connector 104 connects the slider 102 and the movable member 106.

[0044] To optimize the arrangement of the components, the gas particulate matter detection device further includes:

[0045] The suction pipe and the suction pump are respectively installed on the back of the bracket. One end of the suction pipe is connected to the second gas channel, and the other end is connected to the suction pump.

[0046] To prevent the paper tape from deviating during movement, further, such as Figure 2 As shown, the gas particulate matter detection device further includes:

[0047] A first guide member 24 and a second guide member 25 are respectively disposed on both sides of the second component 5 and each has a guide groove that allows the paper tape 3 to pass through. The width of the guide groove matches the width of the paper tape 3.

[0048] To prevent airflow from impacting the detector receiver located within the first component, the first gas channel is further positioned perpendicular to the second gas channel.

[0049] The method for detecting particulate matter in gas according to an embodiment of the present invention includes the following steps:

[0050] (A1) The first driving unit drives the radiation source 65 to move upward, and the radiation source 6 leaves the paper tape 3; the blank paper tape 3 moves to the lower side of the radiation source 6;

[0051] (A2) The first driving unit drives the radiation source 6 to move downward, squeezing the blank paper tape 3; the second driving unit drives the moving part 106 to move forward and no longer block the receiving end of the detector 2. The rays emitted by the radiation source 6 pass through the paper tape 3 and the second component 5 in sequence, and are received by the receiving end of the detector 2 located in the first component 4, thus obtaining the blank signal of the paper tape 3.

[0052] (A3) The second driving unit drives the moving part 106 to move in the opposite direction, enter the first component 4, and block the receiving end; the gas passes through the sample inlet tube 8, the paper tape 3 and the second component 5 in sequence, and the particulate matter in the gas is intercepted by the paper tape 3;

[0053] (A4) The second driving unit drives the moving part 106 to move forward, no longer blocking the receiving end; the rays emitted by the radiation source 6 pass through the particles, paper tape 3 and the second component 5 in sequence, and are received by the receiving end of the detector 2 to obtain the measurement signal of the particles on the paper tape 3.

[0054] (A5) Based on the measured signal and the blank signal, the particulate matter content in the gas is obtained.

[0055] In order to stably and reliably drive the moving part 106 to move forward and backward, the second driving unit further operates as follows:

[0056] The motor drives the rotating disk 101 to rotate, and the column 105 on the rotating disk 101 rotates accordingly, thereby dragging the sliding member 103 to move on the linear guide rail 103, thereby driving the moving member 106 to translate.

[0057] The column 105 is engaged in the limiting groove of the sliding member 102. The angle between the extending direction of the limiting groove and the extending direction of the guide rail 103 is a right angle or an acute angle. The sliding member 1026 and the moving member 106 are connected by the connecting member 104.

[0058] To prevent airflow from entering the first component 4 and impacting the receiver of the detector 2, in step (A3), the gas passes through the first gas channel and the second gas channel in the second component 5 in sequence, and then enters the extraction pipe and the extraction pump.

[0059] To ensure a reasonable layout of the components, the first component 4 and the second component 5 are fixed together and positioned on the front of the bracket. The suction pipe and the suction pump are positioned on the back of the bracket. The suction pipe passes through the bracket and connects to the second gas channel.

[0060] To prevent the paper tape from deviating during movement, the two ends of the paper tape 3 are respectively wrapped around the first wheel 13 and the second wheel 14, and respectively pass through the guide grooves on the first guide member 24 and the second guide member 25. The width of the guide groove matches the width of the paper tape. The first guide member 24 and the second guide member 25 are respectively arranged on both sides of the second component 5.

[0061] Example 2:

[0062] An example of the application of the gas particulate matter detection device according to Embodiment 1 of the present invention in atmospheric detection.

[0063] In this application example, such as Figure 1 As shown, the sampling unit includes a paper tape 3, a first round 13 and a second round 14, and the detection unit includes a radiation source 6 and a detector 2. The sampling unit and the detection unit are mounted on a support.

[0064] The first component has a through hole, and the receiving end of the detector 2 is located in the through hole; the first component has a groove that allows the moving part 106 to pass through; the second component 5 has a first gas channel and a second gas channel communicating with the sample inlet tube 8, the second component 5 and the first component 4 are fixedly connected and are disposed on the support; the first guide 24 and the second guide 25 are respectively disposed on both sides of the second component 5, and each has a guide groove that allows the paper tape 3 to pass through, the width of the guide groove matching the width of the paper tape 3; the paper tape 3 is located on the upper side of the second component; the suction pipe and the suction pump are respectively disposed on the back of the support, one end of the suction pipe passes through the hole 201 on the support and communicates with the second gas channel, and the other end is connected to the suction pump;

[0065] The first driving unit is used to drive the radiation source 6 to move vertically, so that when the radiation source 6 squeezes the paper tape 3, the gas passes through the sample inlet tube 8, the first gas channel and the second gas channel (perpendicular to the first gas channel) in sequence, and the radiation source 6 is in the gas path;

[0066] like Figure 3-4 As shown, in the second drive unit, the motor is fixed on the back of the bracket and drives the rotating disk 101 to rotate. The rotating disk 101 is provided with a column 105. The sliding member 102 is provided on the guide rail 103 and has a limiting groove that allows the column 105 to be inserted. The angle between the extension direction of the limiting groove and the extension direction of the guide rail 103 is a right angle or an acute angle. The connecting member 104 connects the sliding member 102 and the moving member 106, so that when the second drive unit drives the moving member 106 to move back and forth, the moving member 106 can block the receiving end as needed.

[0067] The method for detecting particulate matter in gas according to this embodiment of the invention, that is, the working method of the particulate matter detection device of this embodiment, includes the following steps:

[0068] (A1) The first driving unit drives the radiation source 65 to move upward, and the radiation source 6 leaves the paper tape 3; the blank paper tape 3 moves to the lower side of the radiation source 6;

[0069] (A2) The first driving unit drives the radiation source 6 to move downward, squeezing the blank paper tape 3; the second driving unit drives the moving part 106 to move forward and no longer block the receiving end of the detector 2. The rays emitted by the radiation source 6 pass through the paper tape 3 and the second component 5 in sequence, and are received by the receiving end of the detector 2 located in the first component 4, thus obtaining the blank signal of the paper tape 3.

[0070] (A3) The second driving unit drives the moving part 106 to move in the opposite direction, enter the first component 4, and block the receiving end; the gas passes through the sample tube 8, the paper tape 3, and the first gas channel and the second gas channel in the second component 5 in sequence, and the particulate matter in the gas is intercepted by the paper tape 3.

[0071] (A4) The second driving unit drives the moving part 106 to move forward, no longer blocking the receiving end; the rays emitted by the radiation source 6 pass through the particles, paper tape 3 and the second component 5 in sequence, and are received by the receiving end of the detector 2 to obtain the measurement signal of the particles on the paper tape 3.

[0072] (A5) Based on the measured signal and the blank signal, the particulate matter content in the gas is obtained.

[0073] In the above process, the second driving unit operates as follows:

[0074] The motor drives the rotating disk 101 to rotate counterclockwise in the upper half (lower half) circle. The column 105 on the rotating disk 101 rotates with it, thereby dragging the sliding member 103 to move forward (reverse) on the linear guide rail 103, thereby driving the moving member 106 to translate forward (reverse).

[0075] The column 105 is engaged in the limiting groove of the sliding member 102. The angle between the extending direction of the limiting groove and the extending direction of the guide rail 103 is a right angle or an acute angle. The sliding member 1026 and the moving member 106 are connected by the connecting member 104.

[0076] Example 3:

[0077] The application example of the gas particulate matter detection device according to Embodiment 1 of the present invention in atmospheric detection differs from Embodiment 2 in that:

[0078] The second drive unit uses other drive methods, such as a combination of a motor and a conversion module. The conversion module converts the rotation of the motor into linear movement, such as by using a lead screw.

Claims

1. A gas particulate matter detection device, comprising a sample inlet tube, a sampling unit, and a detection unit, wherein the sampling unit comprises a paper tape, a first wheel, and a second wheel, and the detection unit comprises a radiation source and a detector, wherein the sampling unit and the detection unit are mounted on a support; characterized in that, The gas particulate matter detection device further includes: A first component has a through-hole, and the receiving end of the detector is located within the through-hole; the first component has a groove that allows a movable part to pass through; The second component has a first gas channel and a second gas channel communicating with the sample inlet tube. The second component is disposed on the upper side of the first component and is fixedly connected to the first component, and is disposed on the support. The paper tape is located on the upper side of the second component. The first driving unit is used to drive the radiation source to move vertically, so that when the radiation source squeezes the paper tape, the gas passes through the sample inlet tube, the first gas channel and the second gas channel in sequence, and the radiation source is in the gas path; The moving part and the second driving unit are used to drive the moving part to move back and forth, so that during the air extraction, the moving part blocks the receiving end to prevent the airflow from impacting the receiving end; The air extraction pipe and the air extraction pump are respectively disposed on the back of the bracket. One end of the air extraction pipe passes through a hole on the bracket and connects to the second gas channel, and the other end is connected to the air extraction pump.

2. The gas particulate matter detection device according to claim 1, characterized in that, The second drive unit includes: A motor and a rotating disk, wherein the motor is fixed on the bracket and drives the rotating disk to rotate, and a column is provided on the rotating disk; A sliding member is disposed on a guide rail and has a limiting groove that allows the column to be engaged. The angle between the extending direction of the limiting groove and the extending direction of the guide rail is a right angle or an acute angle. A connector that connects the sliding member and the moving member.

3. The gas particulate matter detection device according to claim 1, characterized in that, The gas particulate matter detection device further includes: A first guide and a second guide are respectively disposed on both sides of the second component and each has a guide groove that allows the paper tape to pass through, the width of the guide groove matching the width of the paper tape.

4. The gas particulate matter detection device according to claim 1, characterized in that, The first gas channel is positioned perpendicular to the second gas channel.

5. A method for detecting particulate matter in gas implemented by the detection device according to any one of claims 1-4, the method comprising the following steps: A1. The first driving unit drives the radiation source to move upward, and the radiation source leaves the paper tape; the blank paper tape moves to the lower side of the radiation source; A2. The first driving unit drives the radiation source to move downward, squeezing the blank paper tape; the second driving unit drives the moving part to move forward and no longer block the receiving end of the detector. The rays emitted by the radiation source pass through the paper tape and the second component in sequence and are received by the receiving end of the detector located in the first component to obtain the blank signal of the paper tape; the second component is located on the upper side of the first component. A3. The second driving unit drives the moving part to move in the opposite direction, enters the first component, and blocks the receiving end; the gas passes through the sample inlet tube, the paper tape, the first gas channel and the second gas channel in the second component in sequence, and then enters the suction tube and the suction pump, and the particulate matter in the gas is intercepted by the paper tape; A4. The second driving unit drives the moving part to move forward, no longer blocking the receiving end; the rays emitted by the radiation source pass through the particles, the paper tape and the second component in sequence, and are received by the receiving end of the detector to obtain the measurement signal of the particles on the paper tape; A5. Based on the measured signal and the blank signal, obtain the particulate matter content in the gas.

6. The method for detecting particulate matter in gas according to claim 5, characterized in that, The second drive unit operates as follows: The motor drives the rotating disk to rotate, and the column on the rotating disk rotates accordingly, thereby dragging the sliding component to move on the linear guide rail, thereby driving the moving component to translate. The column is fitted into the limiting groove of the sliding member, and the angle between the extending direction of the limiting groove and the extending direction of the guide rail is a right angle or an acute angle. The sliding member and the moving member are connected by a connector.

7. The method for detecting particulate matter in gas according to claim 5, characterized in that, The first and second components are fixed together and disposed on the front of the bracket. The suction pipe and the suction pump are disposed on the back of the bracket. The suction pipe passes through the bracket and connects to the second gas channel.

8. The method for detecting particulate matter in gas according to claim 5, characterized in that, The two ends of the paper tape are respectively wound around the first wheel and the second wheel, and respectively pass through the guide grooves on the first guide and the second guide, the width of the guide groove matching the width of the paper tape; the first guide and the second guide are respectively disposed on both sides of the second component.

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