Gas detection system based on TDLAS (tunable diode laser absorption spectroscopy) technology

Abstract

The utility model provides a gas detection system based on a TDLAS (tunable diode laser absorption spectroscopy) technology. The gas detection system comprises a first detection unit, a processing unit, a second detection unit and a control transmission unit, the first detection unit is used for detecting the pressure, humidity and dust concentration of gas and transmitting the detected data to the control transmission unit; the control transmission unit controls the first detection unit to convey gas to the processing unit or the second detection unit according to the detected data; the processing unit is used for removing dust, or dehumidifying, or removing dust and dehumidifying the gas conveyed by the first detection unit; the treated gas is conveyed to the second detection unit; the second detection unit adopts a TDLAS (Tunable Diode Laser Absorption Spectroscopy) device to detect the concentration of the gas conveyed by the first detection unit or the processing unit; the detected gas concentration is transmitted to the control transmission unit; the control transmission unit uploads the gas concentration result; by means of the system, the gas detection precision can be improved.

Description

Technical Field

[0001] The utility model relates to the field of gas monitoring, in particular to a gas detection system based on TDLAS technology. Background Art

[0002] Tunable semiconductor laser absorption spectroscopy (TDLAS) is a technique based on infrared absorption spectroscopy. It leverages the principle of molecular frequency-selective absorption to achieve high-resolution quantitative analysis of gas concentrations by measuring the spectral response of laser light absorbed by gases. This technique offers advantages such as high sensitivity, high spectral resolution, and rapid response, making it widely used in trace gas detection and the diagnosis of toxic and hazardous industrial waste gases.

[0003] However, in practical applications, high humidity and high dust environments pose certain challenges to the application of TDLAS technology. For example, water vapor and other dust particles can affect laser transmission and measurement accuracy, thereby interfering with gas detection results.

[0004] Therefore, in order to solve the above technical problems, it is urgent to propose a new technical means. Utility Model Content

[0005] In view of this, in order to reduce the impact of humidity and dust on gas concentration detection, the utility model proposes a gas detection system that combines dehumidification and dust removal.

[0006] The utility model provides a gas detection system based on TDLAS technology, comprising a first detection unit, a processing unit, a second detection unit and a control transmission unit;

[0007] The first detection unit is used to detect the pressure, humidity and dust concentration of the target gas, and transmit the detected pressure, humidity and dust concentration to the control transmission unit;

[0008] The control transmission unit controls the first detection unit to transport the gas to the processing unit or the second detection unit according to the detected humidity and dust concentration;

[0009] The processing unit is used to remove dust, or dehumidify, or remove dust and dehumidify the gas delivered by the first detection unit; and deliver the treated gas to the second detection unit;

[0010] The second detection unit uses a TDLAS device to detect the concentration of the gas delivered by the first detection unit or the processing unit; and transmits the detected gas concentration to the control transmission unit; and the control transmission unit uploads the gas concentration result.

[0011] Furthermore, the processing unit includes a second chamber and a third chamber; the second chamber is connected to the third chamber through a pipeline; a dust treatment device is provided in the second chamber, and the dust treatment device is used to reduce the dust concentration of the gas; the third chamber is provided with a dehumidification device; the dehumidification device is used to reduce the humidity of the gas and transport the gas with reduced humidity to the second detection unit;

[0012] The second chamber is provided with a second air inlet, a second air outlet I, and a second air outlet II; the second air inlet, the second air outlet I, and the second air outlet II respectively transport gas to the first detection unit, the third chamber, and the second detection unit through pipelines; the second air inlet, the second air outlet I, and the second air outlet II are respectively provided with a second electrically controlled valve I, a second electrically controlled valve II, and a second electrically controlled valve III; the control input ends of the second electrically controlled valve I, the second electrically controlled valve II, and the second electrically controlled valve III are connected to the control output end of the control transmission unit;

[0013] The third chamber is provided with a third air inlet I, a third air inlet II and a third air outlet; the third air inlet I, the third air inlet II and the third air outlet respectively transport the gas to the first detection unit, the second chamber and the second detection unit through pipelines; the third air inlet I, the third air inlet II and the third air outlet are respectively provided with a third electrically controlled valve I, a third electrically controlled valve II and a third electrically controlled valve III; the control input ends of the third electrically controlled valve I, the third electrically controlled valve II and the third electrically controlled valve III are connected to the control output end of the control transmission unit.

[0014] Furthermore, a second dust sensor is fixedly installed on the inner wall of the second chamber, and the output end of the second dust sensor is connected to the input end of the control transmission unit;

[0015] A second humidity sensor is also fixedly provided on the inner wall of the third chamber, and an output end of the second humidity sensor is connected to an input end of the control transmission unit.

[0016] Furthermore, the first detection unit includes a first chamber, a pressure sensor, a first humidity sensor, and a first dust sensor; the pressure sensor, the first humidity sensor, and the first dust sensor are fixedly arranged on the inner wall of the first chamber; the output ends of the pressure sensor, the first humidity sensor, and the first dust sensor are connected to the input end of the control transmission unit;

[0017] The first chamber is provided with a first air inlet, a first air outlet I, a first air outlet II and a first air outlet III; the first air outlet I and the first air outlet II are connected to the second chamber and the third chamber respectively through pipelines; the first air outlet III transports the gas to the second detection unit through the pipeline; the first air outlet I, the first air outlet II and the first air outlet III are respectively provided with a first electrically controlled valve I, a first electrically controlled valve II and a first electrically controlled valve III; the control input ends of the first electrically controlled valve I, the first electrically controlled valve II and the first electrically controlled valve III are all connected to the control output end of the control transmission unit.

[0018] Furthermore, the second detection unit includes a fourth chamber and a TDLAS device; the fourth chamber is used to store the gas delivered by the first detection unit or the processing unit, and the TDLAS device is used to detect the gas concentration in the fourth chamber and transmit the detected gas concentration to the control transmission unit;

[0019] The fourth chamber is provided with a fourth air inlet I, a fourth air inlet II, a fourth air inlet III and a fourth air outlet; the fourth air inlet I, the fourth air inlet II and the fourth air inlet III are connected with the first air outlet III, the second air outlet II and the third air outlet respectively through pipelines; the fourth air inlet I, the fourth air inlet II, the fourth air inlet III and the fourth air outlet are respectively provided with a fourth electrically-controlled valve I, a fourth electrically-controlled valve II, a fourth electrically-controlled valve III and a fourth electrically-controlled valve IV; the control input ends of the fourth electrically-controlled valve I, the fourth electrically-controlled valve II, the fourth electrically-controlled valve III and the fourth electrically-controlled valve IV are connected to the control output end of the control transmission unit.

[0020] Furthermore, a temperature control circuit is included, and the temperature control circuit is used to control the operating temperature of the laser in the TDLAS device.

[0021] Furthermore, the control transmission unit includes a controller, a wireless transmission unit and a memory;

[0022] The controller is in communication with the memory; the controller uploads the gas concentration detection result via the wireless transmission unit.

[0023] Furthermore, it also includes a clock circuit and a positioning circuit; the clock circuit and the positioning circuit are respectively connected to the controller for communication.

[0024] The beneficial effects of this utility model are: By combining dehumidification and dust removal methods, this utility model optimizes the application of TDLAS technology in complex environments. By pre-treating high-humidity and high-dust gases to remove moisture and suspended particles, TDLAS technology is then used to accurately measure gas concentration, ensuring the stability and reliability of the detection system. BRIEF DESCRIPTION OF THE DRAWINGS

[0025] The present invention will be further described below with reference to the accompanying drawings and embodiments:

[0026] Figure 1 This is a schematic diagram of the system structure of the utility model.

[0027] Figure 2 It is a structural diagram of the corresponding device of the utility model.

[0028] Figure numerals: 1-first chamber, 1.1-first air inlet, 2-second chamber, 3-third chamber, 4-fourth chamber, 4.1-fourth air outlet, 5-pressure sensor, 6-first dust sensor, 7-first humidity sensor, 8-second dust sensor, 9-second humidity sensor. DETAILED DESCRIPTION

[0029] The following is a further description of the present invention with reference to the accompanying drawings:

[0030] The utility model provides a gas detection system based on TDLAS technology, comprising a first detection unit, a processing unit, a second detection unit and a control transmission unit;

[0031] The first detection unit is used to detect the pressure, humidity and dust concentration of the target gas, and transmit the detected pressure, humidity and dust concentration to the control transmission unit;

[0032] The control transmission unit controls the first detection unit to transport the gas to the processing unit or the second detection unit according to the detected humidity and dust concentration;

[0033] The processing unit is used to remove dust, or dehumidify, or remove dust and dehumidify the gas delivered by the first detection unit; and deliver the treated gas to the second detection unit;

[0034] The second detection unit uses a TDLAS device to detect the concentration of gas delivered by the first detection unit or processing unit and transmits the detected gas concentration to the control transmission unit, which then uploads the gas concentration result. This system can reduce the impact of moisture and dust on gas concentration measurement and improve the accuracy of gas concentration detection.

[0035] In this embodiment, the processing unit includes a second chamber 2 and a third chamber 3; the second chamber 2 is connected to the third chamber 3 through a pipeline; a dust treatment device is provided in the second chamber 2, and the dust treatment device is used to reduce the dust concentration of the gas; the third chamber 3 is provided with a dehumidification device; the dehumidification device is used to reduce the humidity of the gas and transport the gas with reduced humidity to the second detection unit;

[0036] Among them, dust treatment devices include but are not limited to bag dust collectors, cyclone dust collectors, electrostatic dust collectors and inertial dust collectors; there is no limitation on dust treatment devices, and users can choose according to economic conditions and the type of detected gas. When users do not have requirements, efficient, economical and safe dust treatment devices should be selected; the dehumidification devices include but are not limited to cooling dehumidifiers, solution dehumidifiers and adsorption dehumidifiers; solution dehumidifiers should use solutions that do not react with gases; the specific dehumidification device is selected according to needs; the aforementioned devices are all existing technologies, and their specific structures are not described in detail here;

[0037] The second chamber 2 is provided with a second air inlet, a second air outlet I, and a second air outlet II; the second air inlet, the second air outlet I, and the second air outlet II respectively transport gas to the first detection unit, the third chamber 3, and the second detection unit through pipelines; the second air inlet, the second air outlet I, and the second air outlet II are respectively provided with a second electrically controlled valve I, a second electrically controlled valve II, and a second electrically controlled valve III; the control input ends of the second electrically controlled valve I, the second electrically controlled valve II, and the second electrically controlled valve III are connected to the control output end of the control transmission unit; the electrically controlled valve in this application may be a solenoid valve, an electric control valve, etc.

[0038] The third chamber 3 is provided with a third air inlet I, a third air inlet II and a third air outlet; the third air inlet I, the third air inlet II and the third air outlet respectively transport gas to the first detection unit, the second chamber 2 and the second detection unit through pipelines; the third air inlet I, the third air inlet II and the third air outlet are respectively provided with a third electrically controlled valve I, a third electrically controlled valve II and a third electrically controlled valve III; the control input ends of the third electrically controlled valve I, the third electrically controlled valve II and the third electrically controlled valve III are connected to the control output end of the control transmission unit;

[0039] Openable windows (not shown) are also provided on the second chamber 2 and the third chamber 3 to allow cleaning of the internal devices. The above devices can remove dust and moisture from the gas, providing a basis for improving detection accuracy.

[0040] In this embodiment, a second dust sensor 8 is further fixedly provided on the inner wall of the second chamber 2, and the output end of the second dust sensor 8 is connected to the input end of the control transmission unit;

[0041] A second humidity sensor 9 is also fixedly provided on the inner wall of the third chamber 3 , and the output end of the second humidity sensor 9 is connected to the input end of the control transmission unit;

[0042] The second dust sensor 8 is used to detect the dust concentration in the second chamber 2, and can determine whether the gas reaches a preset dust concentration standard based on the detected dust concentration;

[0043] The second humidity sensor 9 is used to detect the humidity in the third chamber 3. It can determine whether the gas meets the preset humidity standard based on the detected humidity. The above device can ensure that the target gas meets the detection standard.

[0044] In this embodiment, the first detection unit includes a first chamber 1, a pressure sensor 5, a first humidity sensor 7 and a first dust sensor 6; the pressure sensor 5, the first humidity sensor 7 and the first dust sensor 6 are fixedly arranged on the inner wall of the first chamber 1; the output ends of the pressure sensor 5, the first humidity sensor 7 and the first dust sensor 6 are connected to the input end of the control transmission unit; the pressure sensor 5 is used to detect the pressure in the first chamber 1. Since the gas pressure will affect the accuracy of the gas concentration detection, the gas pressure must be strictly monitored. When the first chamber 1 reaches the target pressure, the first air inlet 1.1 is closed; the first air inlet 1.1 can be closed by a mechanical structure or an electrically controlled valve, which is not limited here; in order to ensure that the first chamber 1 reaches the target pressure, an existing pressure regulating device can also be added to the first chamber 1 so that the air pressure in the first chamber 1 is always maintained within the target pressure range;

[0045] The first chamber 1 is provided with a first air inlet 1.1, a first air outlet I, a first air outlet II and a first air outlet III; the first air outlet I and the first air outlet II are connected to the second chamber 2 and the third chamber 3 through pipelines respectively; the first air outlet III transports the gas to the second detection unit through the pipeline; the first air outlet I, the first air outlet II and the first air outlet III are respectively provided with a first electrically controlled valve I, a first electrically controlled valve II and a first electrically controlled valve III; the control input ends of the first electrically controlled valve I, the first electrically controlled valve II and the first electrically controlled valve III are all connected to the control output end of the control transmission unit.

[0046] Furthermore, the second detection unit includes a fourth chamber 4 and a TDLAS device (not shown in the figure); the fourth chamber 4 is used to store the gas delivered by the first detection unit or the processing unit, and the TDLAS device is used to detect the gas concentration in the fourth chamber 4 and transmit the detected gas concentration to the control transmission unit; the TDLAS device adopts an existing device, and its structure is not described in detail here;

[0047] The fourth chamber 4 is provided with a fourth air inlet I, a fourth air inlet II, a fourth air inlet III, and a fourth air outlet 4.1; the fourth air inlet I, the fourth air inlet II, and the fourth air inlet III are connected to the first air outlet III, the second air outlet II, and the third air outlet respectively through pipelines; the fourth air inlet I, the fourth air inlet II, the fourth air inlet III, and the fourth air outlet 4.1 are respectively provided with a fourth electrically controlled valve I, a fourth electrically controlled valve II, a fourth electrically controlled valve III, and a fourth electrically controlled valve IV; the control input ends of the fourth electrically controlled valve I, the fourth electrically controlled valve II, the fourth electrically controlled valve III, and the fourth electrically controlled valve IV are connected to the control output end of the control transmission unit. Through the above device, it is possible to determine whether the target gas requires dehumidification or dust removal, providing a basis for subsequent processing.

[0048] In this embodiment, a temperature control circuit is also included, which is used to control the operating temperature of the laser in the TDLAS device. Since temperature changes can cause instability in the output power of the laser and drift in the laser emission wavelength, which ultimately affects the detection of gas concentration, the operating temperature of the laser must be controlled. The temperature control circuit uses an existing temperature control circuit, which will not be described in detail here.

[0049] In this embodiment, the control transmission unit includes a controller, a wireless transmission unit and a memory;

[0050] The controller is communicatively connected to the memory; the controller uploads the gas concentration detection results via the wireless transmission unit; the controller can be a single-chip microcomputer or an industrial computer; the wireless transmission unit includes but is not limited to a Wi-Fi module, a Bluetooth device, a 4G module, and a 5G module. The aforementioned device can transmit the detected gas concentration to the cloud or a remote monitoring location.

[0051] This embodiment further includes a clock circuit and a positioning circuit, each of which is in communication with the controller. The clock circuit utilizes an existing circuit to determine the time of gas detection; the positioning circuit can utilize Beidou positioning or GPS positioning circuits to determine the location of the detected gas.

[0052] When the gas concentration needs to be detected, the target gas is input into the first chamber; and the chamber to which the gas should be transported is determined (determined by the control transmission unit) based on the detected humidity and dust concentration;

[0053] When the target gas is not a high-humidity and high-dust gas, the controller opens the pipe connecting the first chamber and the fourth chamber, and directly transports the target gas to the fourth chamber for detection; wherein, opening the connecting pipe means opening the electric control valves at both ends of the connecting pipe;

[0054] When the target gas is a high-dust gas but not a high-humidity gas, the controller opens the pipe connecting the first chamber and the second chamber, and transports the target gas to the second chamber for dust removal; when the dust concentration in the second chamber reaches a preset standard, the controller opens the pipe connecting the second chamber and the fourth chamber, and transports the target gas to the fourth chamber for detection;

[0055] If the target gas is high-dust and high-humidity gas, after the dust removal process is performed in the second chamber, the controller will open the pipe connecting the second chamber and the third chamber, and transport the target gas to the third chamber for dehumidification; when the target gas meets the preset humidity standard, the controller will open the pipe connecting the third chamber and the fourth chamber, and transport the target gas to the fourth chamber for testing;

[0056] When the target gas is a high-humidity gas rather than a high-dust gas, the controller opens the pipe connecting the first chamber and the third chamber, and transports the target gas to the third chamber for dehumidification. When the humidity of the target gas reaches the preset target, the controller opens the pipe connecting the third chamber and the fourth chamber, and transports the target gas to the fourth chamber for detection.

[0057] Finally, it should be noted that the above embodiments are only used to illustrate the technical solution of the utility model and are not limiting. Although the utility model is described in detail with reference to the preferred embodiments, ordinary technicians in this field should understand that the technical solution of the utility model can be modified or replaced by equivalents without departing from the purpose and scope of the technical solution of the utility model, which should be included in the scope of the claims of the utility model.

Claims

1. A gas detection system based on TDLAS technology, characterized by: It includes a first detection unit, a processing unit, a second detection unit and a control transmission unit; The first detection unit is used to detect the pressure, humidity and dust concentration of the target gas, and transmit the detected pressure, humidity and dust concentration to the control transmission unit; The control transmission unit controls the first detection unit to transport the gas to the processing unit or the second detection unit according to the detected humidity and dust concentration; The processing unit is used to remove dust, or dehumidify, or remove dust and dehumidify the gas delivered by the first detection unit; and deliver the treated gas to the second detection unit; The second detection unit uses a TDLAS device to detect the concentration of the gas delivered by the first detection unit or the processing unit; and transmits the detected gas concentration to the control transmission unit; and the control transmission unit uploads the gas concentration result.

2. The gas detection system based on TDLAS technology according to claim 1, characterized in that: The processing unit includes a second chamber and a third chamber; the second chamber is connected to the third chamber through a pipeline; a dust treatment device is provided in the second chamber, and the dust treatment device is used to reduce the dust concentration of the gas; the third chamber is provided with a dehumidification device; the dehumidification device is used to reduce the humidity of the gas and transmit the gas with reduced humidity to the second detection unit; The second chamber is provided with a second air inlet, a second air outlet I, and a second air outlet II; the second air inlet, the second air outlet I, and the second air outlet II respectively transport gas to the first detection unit, the third chamber, and the second detection unit through pipelines; the second air inlet, the second air outlet I, and the second air outlet II are respectively provided with a second electrically controlled valve I, a second electrically controlled valve II, and a second electrically controlled valve III; the control input ends of the second electrically controlled valve I, the second electrically controlled valve II, and the second electrically controlled valve III are connected to the control output end of the control transmission unit; The third chamber is provided with a third air inlet I, a third air inlet II and a third air outlet; the third air inlet I, the third air inlet II and the third air outlet respectively transport the gas to the first detection unit, the second chamber and the second detection unit through pipelines; the third air inlet I, the third air inlet II and the third air outlet are respectively provided with a third electrically controlled valve I, a third electrically controlled valve II and a third electrically controlled valve III; the control input ends of the third electrically controlled valve I, the third electrically controlled valve II and the third electrically controlled valve III are connected to the control output end of the control transmission unit.

3. The gas detection system based on TDLAS technology according to claim 2, characterized in that: A second dust sensor is further fixedly provided on the inner wall of the second chamber, and an output end of the second dust sensor is connected to an input end of the control transmission unit; A second humidity sensor is also fixedly provided on the inner wall of the third chamber, and an output end of the second humidity sensor is connected to an input end of the control transmission unit.

4. The gas detection system based on TDLAS technology according to claim 2, characterized in that: The first detection unit includes a first chamber, a pressure sensor, a first humidity sensor, and a first dust sensor; the pressure sensor, the first humidity sensor, and the first dust sensor are fixedly arranged on the inner wall of the first chamber; the output ends of the pressure sensor, the first humidity sensor, and the first dust sensor are connected to the input end of the control transmission unit; The first chamber is provided with a first air inlet, a first air outlet I, a first air outlet II and a first air outlet III; the first air outlet I and the first air outlet II are connected to the second chamber and the third chamber respectively through pipelines; the first air outlet III transports the gas to the second detection unit through the pipeline; the first air outlet I, the first air outlet II and the first air outlet III are respectively provided with a first electrically controlled valve I, a first electrically controlled valve II and a first electrically controlled valve III; the control input ends of the first electrically controlled valve I, the first electrically controlled valve II and the first electrically controlled valve III are all connected to the control output end of the control transmission unit.

5. The gas detection system based on TDLAS technology according to claim 4, characterized in that: The second detection unit includes a fourth chamber and a TDLAS device; the fourth chamber is used to store the gas delivered by the first detection unit or the processing unit, and the TDLAS device is used to detect the gas concentration in the fourth chamber and transmit the detected gas concentration to the control transmission unit; The fourth chamber is provided with a fourth air inlet I, a fourth air inlet II, a fourth air inlet III and a fourth air outlet; the fourth air inlet I, the fourth air inlet II and the fourth air inlet III are connected with the first air outlet III, the second air outlet II and the third air outlet respectively through pipelines; the fourth air inlet I, the fourth air inlet II, the fourth air inlet III and the fourth air outlet are respectively provided with a fourth electrically-controlled valve I, a fourth electrically-controlled valve II, a fourth electrically-controlled valve III and a fourth electrically-controlled valve IV; the control input ends of the fourth electrically-controlled valve I, the fourth electrically-controlled valve II, the fourth electrically-controlled valve III and the fourth electrically-controlled valve IV are connected to the control output end of the control transmission unit.

6. The gas detection system based on TDLAS technology according to claim 5, characterized in that: The device also includes a temperature control circuit, which is used to control the operating temperature of the laser in the TDLAS device.

7. The gas detection system based on TDLAS technology according to any one of claims 3 or 6, characterized in that: The control transmission unit includes a controller, a wireless transmission unit and a memory; The controller is in communication with the memory; the controller uploads the gas concentration detection result via the wireless transmission unit.

8. The gas detection system based on TDLAS technology according to claim 7, characterized in that: It also includes a clock circuit and a positioning circuit; the clock circuit and the positioning circuit are respectively connected to the controller for communication.

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