Optical gas detection device

Abstract

The utility model provides an optical gas detection device. The optical gas detection device comprises a cylinder body, a first integrated detection mechanism and a second integrated detection mechanism, a first integrated detection mechanism and a second integrated detection mechanism are arranged on the two sides of the cylinder in a mirror image mode. The first integrated detection mechanism comprises a cover plate, a first fixing seat, a high-sensitivity detection assembly and a first low-sensitivity detection assembly, the first fixing seat is arranged at one end of the cylinder in a sleeving mode, and a first light-transmitting piece is arranged on the side, away from the cylinder, of the first fixing seat through the cover plate; a first light-transmitting hole and a first light-transmitting groove are sequentially formed in a vertical plate of the first fixing base in a penetrating mode along the Y axis, and a high-sensitivity detection assembly and a first low-sensitivity detection assembly are arranged on the sides, close to and away from the cover plate, of the vertical plate of the first fixing base correspondingly. A second light-transmitting hole and a second light-transmitting groove are respectively formed in positions, close to the first light-transmitting hole and the first light-transmitting groove, of the first low-sensitivity detection assembly. Through the structural arrangement, synchronous detection of multi-component and wide-concentration-range gas is realized.

Description

TECHNICAL FIELD

[0001] The utility model relates to the technical field of gas detection, specifically to an optical gas detection device. BACKGROUND

[0002] Absorption spectrum detection technology is based on Beer-Lambert law, and realizes non-invasive real-time detection through gas characteristic spectrum, has the advantages of chemical interference resistance, long service life and high safety, and is especially suitable for dynamic reaction process monitoring, however, existing spectrum detection technology relies on a single method, and it is difficult to meet the complex needs of multi-component and wide concentration range gas in environmental monitoring:

[0003] Cavity enhanced absorption spectrum technology (CEAS) can improve the gas detection sensitivity to 10 -12 The order of magnitude by extending the optical path through a resonant cavity, which performs excellently in trace VOCs, CH4 and other gas detection, but its dynamic range is limited, and high concentration gas can easily cause signal saturation, which cannot be directly applied to industrial emission and other scenes that require wide range detection;

[0004] Herriott type gas absorption cell as the core component of TDLAS sensor, with multi-reflection light path design to optimize the optical path, has the characteristics of high mechanical stability, adjustable light path, etc., such as the contrast file with publication number CN214041118U, which discloses a long optical path gas absorption cell, comprising: a gas cell tube, a vacuum cavity is arranged in the gas cell tube, the gas cell tube is provided with an inlet and outlet gas port and a light transmission window, the inlet and outlet gas port is communicated with the vacuum cavity; The first reflecting mirror is arranged in the vacuum cavity, and the first reflecting mirror is aligned with the light transmission window; The second reflecting mirror is arranged in the vacuum cavity; The filling body is arranged in the vacuum cavity, and the two ends of the filling body are connected with the first reflecting mirror and the second reflecting mirror respectively; By setting the filling body between the two reflecting mirrors, the volume in the vacuum cavity can be greatly reduced, and the gas exchange speed can be improved, but the optical path of the traditional single optical path structure is fixed, which leads to narrow concentration detection range, and it is difficult to balance low concentration sensitivity and high concentration anti-saturation ability;

[0005] In the field of environmental protection monitoring (such as industrial flue gas, air pollution tracing, etc.), it is often necessary to detect multiple gases (such as SO2 / NO2 / CO and trace HF, benzene series) simultaneously, and the gas concentration span is large (ppm to ppt level); The existing single technology equipment needs to be switched or stacked, which leads to high system complexity and low detection efficiency, and the cooperation of multiple devices is easy to cause data deviation due to environmental interference (such as temperature and humidity change, mechanical vibration). UTILITY MODEL CONTENT

[0006] The technical problem to be solved by this invention is how to integrate high and low sensitivity detection to achieve simultaneous detection of multi-component gases with a wide concentration range.

[0007] This utility model solves the above-mentioned technical problems through the following technical means:

[0008] An optical gas detection device includes a cylinder (1), a first integrated detection mechanism (3), and a second integrated detection mechanism (4); the first integrated detection mechanism (3) and the second integrated detection mechanism (4) are mirror images of each other on both sides of the cylinder (1); the first integrated detection mechanism (3) includes a cover plate (31), a first fixing seat (32), a high-sensitivity detection component (34), and a first low-sensitivity detection component (36); the first fixing seat (32) is sleeved on one end of the cylinder (1), and the side of the first fixing seat (32) away from the cylinder (1) is connected to the cover plate (31). 1) A first light-transmitting sheet (30) is provided. A first light-transmitting hole (321) and a first light-transmitting groove (322) are sequentially opened along the Y-axis on the vertical plate of the first fixed base (32). A high-sensitivity detection component (34) and a first low-sensitivity detection component (36) are respectively provided on the vertical plate of the first fixed base (32) near the cover plate (31). A second light-transmitting hole (364) and a second light-transmitting groove (363) are respectively opened on the first low-sensitivity detection component (36) near the first light-transmitting hole (321) and the first light-transmitting groove (322).

[0009] Beneficial effects: By setting up the cylinder, the first integrated detection mechanism, and the second integrated detection mechanism, the coordinated operation of the Heriot-Limited Cell and the cavity enhancement system is realized. The light intensity in the central region of the annular spot of the first low-sensitivity detection component of the Heriot-Limited Cell is relatively weak. A groove is dug in this region and a high-sensitivity detection component of the cavity enhancement system is set there, so that the reflection sources of the two systems are concentric and there is no optical path conflict, thus realizing the synchronous detection of multi-component gases with a wide concentration range.

[0010] Furthermore, the size of the first light-transmitting sheet (30) can cover the first light-transmitting hole (321) and the first light-transmitting groove (322), and the size of the second light-transmitting sheet (40) of the second integrated detection mechanism (4) is smaller than the size of the first light-transmitting sheet (30).

[0011] Beneficial effect: By setting the size of the first light-transmitting sheet, it is ensured that the light path of the first light-transmitting sheet can pass through the high-sensitivity detection component and the first light-transmitting hole on the first fixed base vertical plate respectively.

[0012] Furthermore, neither the second fixed base (42) nor the second low-sensitivity detection component (46) of the second integrated detection mechanism (4) has any light-transmitting holes.

[0013] Furthermore, the cylinder (1) is made of a transparent material.

[0014] Beneficial effect: The material of the cylinder is designed to allow for observation of light when adjusting the light source.

[0015] Furthermore, the four corners between the first integrated testing mechanism (3) and the second integrated testing mechanism (4) are all fixed by connecting rods (2).

[0016] Beneficial effects: By setting the connecting rod, the first integrated detection mechanism, the second integrated detection mechanism, and the cylinder are kept basically on the same axis, thereby keeping the optical path basically on the same axis.

[0017] Furthermore, a sealing cap (37) is fixed on the side of the first fixed seat (32) near the cylinder (1), and the sealing cap (37) is sleeved and fixed on the cylinder (1).

[0018] Beneficial effect: The sealing cap prevents gas leakage.

[0019] Furthermore, at least one first tracheal connector (323) is fixed through the outer horizontal plate of the first fixed seat (32) near the cylinder (1), and at least one second tracheal connector (423) is fixed through the outer horizontal plate of the second fixed seat (42) of the second integrated detection mechanism (4) near the cylinder (1).

[0020] Beneficial effects: The first and second air pipe connectors are used for air intake and exhaust.

[0021] Furthermore, the high-sensitivity detection component (34) includes a first mirror mount (341) and a high-reflection mirror (342). The first mirror mount (341) is adjustable and fixed on the vertical plate of the first fixed base (32) through the first adjustment component (33). The high-reflection mirror (342) is fixed through the first mirror mount (341) near the first light transmission groove (322). The high-reflection mirror (342) is set with the first light transmission groove (322) and the second light transmission groove (363) along the same center line.

[0022] Beneficial effects: By setting up a high-reflectivity mirror, it has high reflectivity and a transmittance of about 15%, which enables the cavity enhancement system to detect low-concentration signals, while also having narrowband high resolution capability.

[0023] Furthermore, the first low-sensitivity detection component (36) includes a second mirror mount (361) and a reflector (362). The second mirror mount (361) is adjustablely fixed on the vertical plate of the first fixed base (32) via the second adjustment component (35). The reflector (362) is fixed on the side of the second mirror mount (361) away from the high-sensitivity detection component (34). The second mirror mount (361) and the reflector (362) are both provided with a second light-transmitting groove (363) near the first light-transmitting groove (322). The second mirror mount (361) and the reflector (362) are both provided with a second light-transmitting hole (364) near the first light-transmitting hole (321).

[0024] Beneficial effects: By setting up the reflector, the reflectivity is lower than that of a high-reflectivity mirror and there is no transmittance, which enables the use of a Heriot-Limited Cell to detect high and medium concentration signals, while also having a wide-band fast scanning capability.

[0025] Furthermore, the first light-transmitting hole (321), the first light-transmitting groove (322), the second light-transmitting hole (364), and the second light-transmitting groove (363) are all circular.

[0026] Beneficial effect: By setting the shapes of the first light-transmitting hole, the first light-transmitting groove, the second light-transmitting hole, and the second light-transmitting groove, the circle will not block the light. Attached Figure Description

[0027] Figure 1 This is a perspective view of the optical gas detection device according to Embodiment 1 of this utility model;

[0028] Figure 2 This is a cross-sectional perspective view of the optical gas detection device according to Embodiment 1 of this utility model;

[0029] Figure 3 This is a cross-sectional front view of the first integrated detection mechanism in the optical gas detection device of Embodiment 1 of this utility model;

[0030] Figure 4 This is an exploded view of the first integrated detection mechanism in the optical gas detection device of Embodiment 1 of this utility model. Detailed Implementation

[0031] To make the objectives, technical solutions, and advantages of the embodiments of this utility model clearer, the technical solutions of the embodiments of this utility model will be clearly and completely described below in conjunction with the embodiments of this utility model. Obviously, the described embodiments are only some embodiments of this utility model, not all embodiments. Based on the embodiments of this utility model, all other embodiments obtained by those skilled in the art without creative effort are within the protection scope of this utility model.

[0032] Example 1

[0033] like Figure 1 As shown, this embodiment provides an optical gas detection device, including a cylinder 1, a connecting rod 2, a first integrated detection mechanism 3, and a second integrated detection mechanism 4.

[0034] like Figure 1 As shown, the cylinder 1 is designed to be open from left to right. The cylinder 1 is made of transparent quartz glass and is used to observe the light when adjusting the light. The first integrated detection mechanism 3 and the second integrated detection mechanism 4 are fixedly fixed on the left and right sides of the cylinder 1. The first integrated detection mechanism 3 and the second integrated detection mechanism 4 have the same structure. The four corners between the first integrated detection mechanism 3 and the second integrated detection mechanism 4 are fixed by connecting rods 2. By setting the connecting rods 2, the first integrated detection mechanism 3, the second integrated detection mechanism 4 and the cylinder 1 are basically kept on the same axis, thereby keeping the light path basically on the same axis.

[0035] like Figure 1 , Figure 2 , Figure 3As shown, the first integrated detection mechanism 3 includes a cover plate 31, a first fixed base 32, a first adjusting component 33, a high-sensitivity detection component 34, a second adjusting component 35, a first low-sensitivity detection component 36, and a sealing cover 37. The first fixed base 32 has an "I"-shaped vertical cross-section and is sleeved on one end of the cylinder 1. The cover plate 31 is fixed on the side of the first fixed base 32 away from the cylinder 1, and the sealing cover 37 is fixed on the side of the first fixed base 32 close to the cylinder 1. The sealing cover 37 is sleeved and fixed on the cylinder 1. The connecting rod 2 passes through the sealing cover 37 and the first... The fixing base 32 and the cover plate 31 are fixed together. In this embodiment, the cover plate 31 and the first fixing base 32 are fixed together by a sealing ring. A first mounting groove is formed through the cover plate 31 from left to right. A first light-transmitting sheet 30 is fixed in the first mounting groove. The size of the first light-transmitting sheet 30 can cover the first light-transmitting hole 321 and the first light-transmitting groove 322. The size of the second mounting groove and the second light-transmitting sheet 40 of the second integrated detection mechanism 4 are smaller than the size of the first mounting groove and the first light-transmitting sheet 30, ensuring that the light path of the first light-transmitting sheet 30 can pass through the high-sensitivity detection component 34 and the first light-transmitting hole 322 respectively. A first light-transmitting hole 321 is provided on the vertical plate of the first fixed base 32. In this embodiment, the first mounting groove and the first light-transmitting sheet 30 are fixed together by a pressure ring. The vertical plate of the first fixed base 32 has a first light-transmitting hole 321 and a first light-transmitting groove 322 extending through the left and right sides. The first light-transmitting hole 321 is located near the top, and the first light-transmitting groove 322 is located near the middle. At least one first air pipe connector 323 is fixed through the outer horizontal plate of the first fixed base 32 near the cylinder 1. The second integrated detection mechanism 4 includes a second fixed base 42. The outer horizontal plate of the second fixed base 42 near the cylinder 1 has a first air pipe connector 323. At least one second air pipe connector 423 is fixedly fixed through the horizontal plate. The air pipe connector on one side is used for air intake, and the air pipe connector on the other side is used for air exhaust. In this embodiment, two first air pipe connectors 323 and two second air pipe connectors 423 are provided. The high-sensitivity detection component 34 and the first low-sensitivity detection component 36 are adjustablely fixed on the vertical plate of the first fixed base 32 near the cover plate 31 and away from the cover plate 31, respectively, through the first adjustment component 33 and the second adjustment component 35. There are no light-transmitting holes on the second fixed base 42 and the second low-sensitivity detection component 46 of the second integrated detection mechanism 4.

[0036] like Figure 2 , Figure 3 , Figure 4As shown, the high-sensitivity detection component 34 includes a first mirror mount 341 and a high-reflectivity mirror 342. The first mirror mount 341 is adjustablely fixed to the vertical plate of the first fixed base 32 via the first adjustment component 33. The high-reflectivity mirror 342 is fixedly fixed through the first mirror mount 341 near the first light transmission groove 322. The high-reflectivity mirror 342 is arranged with the first light transmission groove 322 along the same center line and is circular. The high-reflectivity mirror 342 is existing technology and has high reflectivity with a transmittance of about 15%. The first adjustment component 33 includes a first adjustment screw 331 and a first tension spring 332. Multiple first tension springs 332 are provided, and the two ends of each first tension spring 332 are respectively fixed to the first adjustment screw 341. On the vertical plates of the mirror mount 341 and the first fixed base 32, multiple first adjusting screws 331 are provided. Each first adjusting screw 331 is fixed on the first mirror mount 341, and the free end of each first adjusting screw 331 abuts against the vertical plate of the first fixed base 32. The first tension spring 332 has a certain rigidity and can support the weight of the first mirror mount 341 and the high-reflection mirror 342. In this embodiment, three first adjusting screws 331 and two first tension springs 332 are provided. The first adjusting screws 331 and the first tension springs 332 are used to adjust the distance and parallelism between the high-reflection mirror 342 and the vertical plate of the first fixed base 32, further ensuring that the optical path is on the same axis.

[0037] like Figure 2 , Figure 3 , Figure 4As shown, the first low-sensitivity detection component 36 includes a second mirror mount 361 and a reflector 362. The second mirror mount 361 is adjustablely fixed to the vertical plate of the first fixed base 32 via the second adjustment component 35. The reflector 362 is fixed on the side of the second mirror mount 361 away from the high-sensitivity detection component 34. The dimensions of the second mirror mount 361 and the reflector 362 are both larger than the dimensions of the high-reflectivity mirror 342. The second mirror mount 361 and the reflector 362 both have a second light-transmitting groove 363 through them near the first light-transmitting groove 322. The second light-transmitting groove 363 is arranged along the same center line as the high-reflectivity mirror 342. The second mirror mount 361 and the reflector 362 both have a second light-transmitting hole 364 through them near the first light-transmitting hole 321. The reflector 362 is circular. In this embodiment, the reflector 362 is a concave reflector. The reflector 362 is existing technology and has a lower reflectivity than the high-reflectivity mirror 342, with no transmittance. All light-transmitting grooves and holes are circular. It will block the light; the second adjustment component 35 includes a second adjustment screw 351 and a second tension spring 352. Multiple second tension springs 352 are provided, and the two ends of each second tension spring 352 are respectively fixed to the vertical plate of the first fixed base 32 and the second mirror base 361. Multiple second adjustment screws 351 are provided, and each second adjustment screw 351 is fixed to the vertical plate of the first fixed base 32. The free end of each second adjustment screw 351 abuts against the second mirror base 361. The second tension spring 352 has a certain rigidity and can support the weight of the second mirror base 361 and the reflector 362. In this embodiment, three second adjustment screws 351 and four second tension springs 352 are provided. The second adjustment screws 351 and the second tension springs 352 are used to adjust the distance and parallelism between the reflector 362 and the vertical plate of the first fixed base 32, thereby adjusting the distance and parallelism between the high-reflection mirror 342 and the reflector 362, and further ensuring that the light path is on the same axis.

[0038] In use, external light passes through the first light-transmitting plate 30. A portion of the light sequentially passes through the first light-transmitting hole 321 and the second light-transmitting hole 364, undergoing repeated reflections between the first low-sensitivity detection component 36 and the second low-sensitivity detection component 46, and finally exits sequentially through the second light-transmitting hole 364, the first light-transmitting hole 321, and the first light-transmitting plate 30. The other portion of the light sequentially passes through the high-reflection mirror 342, the first light-transmitting groove 322, and the second light-transmitting groove 363, undergoing repeated reflections between the high-reflection mirrors 342 of the two high-sensitivity detection components 34, and finally exits through the second light-transmitting plate 40. After adjusting the optical path, gas is introduced for detection. This device, through geometric multiplexing and coaxial integration design, achieves the coordinated operation of the Heriot-Lewis cell and the cavity enhancement system. The light intensity is weak in the central region of the annular light spot of the Heriot-Lewis cell's reflector 362. A groove is dug in this region, and the high-reflection mirror 342 of the cavity enhancement system is installed, ensuring that the reflection sources of the two systems are concentric and that the optical paths do not conflict. During the detection process, the light source can be switched according to the gas concentration range and detection requirements. Depending on the source wavelength or optical path guidance, the system can be used individually in Heriot-Limited Cell mode, cavity enhancement mode, or both modes in combination. When detecting trace gases, the cavity enhancement system leverages its ultra-high sensitivity to provide detection accuracy at the ppm or even ppb level. When detecting high-concentration gases, the Heriot-Limited Cell utilizes its long optical path and wide dynamic range to avoid signal saturation and ensure detection accuracy. When the two systems are used together, the cavity enhancement system detects low-concentration signals (due to the high reflectivity of the 342 high-reflectivity mirror), while the Heriot-Limited Cell processes high- and medium-concentration signals (due to the low reflectivity of the 362 mirror), achieving full-range detection from trace to high-concentration gases. Simultaneously, the narrow-band high-resolution capability of the cavity enhancement system (due to the high reflectivity of the 342 high-reflectivity mirror) is used for isotope analysis, while the wide-band rapid scanning capability of the Heriot-Limited Cell (due to the low reflectivity of the 362 mirror) is used for multi-component gas detection, acquiring multi-dimensional data. This avoids the errors caused by switching in traditional single-technology equipment, significantly improving detection efficiency and accuracy.

[0039] The above embodiments are only used to illustrate the technical solutions of this utility model, and are not intended to limit it. Although this utility model has been described in detail with reference to the foregoing embodiments, those skilled in the art should understand that modifications can still be made to the technical solutions described in the foregoing embodiments, or equivalent substitutions can be made to some of the technical features. Such modifications or substitutions do not cause the essence of the corresponding technical solutions to deviate from the spirit and scope of the technical solutions of the embodiments of this utility model.

Claims

1. An optical gas sensing device, characterized in that, The application relates to a multi-channel integrated detection device for a multi-channel gas sampling tube. The first integrated detection mechanism (3) and the second integrated detection mechanism (4) are symmetrically arranged on the two sides of the cylinder (1); the first integrated detection mechanism (3) comprises a cover plate (31), a first fixed seat (32), a high-sensitivity detection assembly (34) and a first low-sensitivity detection assembly (36); the first fixed seat (32) is sleeved on one end of the cylinder (1); a first light-transmitting sheet (30) is arranged on the side, away from the cylinder (1), of the first fixed seat (32) through the cover plate (31); a first light-transmitting hole (321) and a first light-transmitting groove (322) are sequentially and throughly arranged on the vertical plate of the first fixed seat (32) along the Y axis; the high-sensitivity detection assembly (34) and the first low-sensitivity detection assembly (36) are arranged on the vertical plate of the first fixed seat (32) close to and away from the cover plate (31) respectively; and a second light-transmitting hole (364) and a second light-transmitting groove (363) are arranged on the first low-sensitivity detection assembly (36) close to the first light-transmitting hole (321) and the first light-transmitting groove (322) respectively.

2. The optical gas sensing device of claim 1, wherein: The size of the first light-transmitting sheet (30) can cover the first light-transmitting hole (321) and the first light-transmitting groove (322); and the size of a second light-transmitting sheet (40) of the second integrated detection mechanism (4) is smaller than that of the first light-transmitting sheet (30).

3. The optical gas sensing device of claim 1, wherein: No light-transmitting hole is arranged on the second fixed seat (42) and the second low-sensitivity detection assembly (46) of the second integrated detection mechanism (4).

4. The optical gas sensing device of claim 1, wherein: The cylinder (1) is made of transparent material.

5. The optical gas sensing device of claim 1, wherein: Connecting rods (2) are arranged at the four corners between the first integrated detection mechanism (3) and the second integrated detection mechanism (4).

6. The optical gas sensing device of claim 1, wherein: A sealing cover (37) is fixed on the side, close to the cylinder (1), of the first fixed seat (32) and is sleeved on the cylinder (1).

7. The optical gas sensing device of claim 1, wherein: At least one first air pipe joint (323) is fixed on the outer peripheral horizontal plate of the side, close to the cylinder (1), of the first fixed seat (32); and at least one second air pipe joint (423) is fixed on the outer peripheral horizontal plate of the side, close to the cylinder (1), of the second fixed seat (42) of the second integrated detection mechanism (4).

8. The optical gas sensing device of claim 1, wherein: The high-sensitivity detection assembly (34) comprises a first mirror seat (341) and a high-reflection mirror (342); the first mirror seat (341) is adjustably fixed on the vertical plate of the first fixed seat (32) through a first adjusting assembly (33); the high-reflection mirror (342) is fixed on the first mirror seat (341) close to the first light-transmitting groove (322); and the high-reflection mirror (342) is arranged on the same center line with the first light-transmitting groove (322) and the second light-transmitting groove (363).

9. The optical gas sensing device of claim 1, wherein: The first low-sensitivity detection assembly (36) comprises a second mirror seat (361) and a mirror (362), the second mirror seat (361) is adjustably fixed on the vertical plate of the first fixing seat (32) through a second adjusting assembly (35), the side, away from the high-sensitivity detection assembly (34), of the second mirror seat (361) is fixed with the mirror (362), and the second mirror seat (361) and the mirror (362) are both provided with a second light transmission groove (363) penetratingly arranged close to the first light transmission groove (322) and are both provided with a second light transmission hole (364) penetratingly arranged close to the first light transmission hole (321).

10. The optical gas sensing device of claim 1, wherein: The first light transmission hole (321), the first light transmission groove (322), the second light transmission hole (364) and the second light transmission groove (363) are all circular.

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