Detection device and detection method

Abstract

A detection device (100) is provided with a first gas cell (1), a first adsorbent (2), a first stimulation unit (3), a first light source (4), a first detector (5), and a measurement unit (102). Gas is introduced into the first gas chamber (1). The first adsorbent (2) is filled in the first gas chamber (1) so as to form a first unfilled space (19) inside the first gas chamber (1), and adsorbs a first target component in the gas. The first unfilled space (19) is a space not filled with the first adsorbent. The first stimulation unit (3) applies a stimulus to the first adsorbent (2), and separates the first target component into the first unfilled space (19). The first light source (4) emits light to the first unfilled space (19). The first detector (5) detects light emitted from the first gas cell (1). The measurement unit (102) measures the first target component on the basis of the output of the first detector (5).

Description

Technical Field

[0001] This disclosure relates to detection apparatus and detection methods, and more specifically, to gas detection apparatus and gas detection methods. Background Technology

[0002] A technique for detecting target components in a gas is known, based on the absorption of pulsed light generated when light passes through it. One example of this technique is cavity ring-down spectroscopy, which concentrates light within a resonator (cavity) and then blocks the light input to the resonator. A detector detects the ring-down signal generated by this blocking, and the target component is detected based on this ring-down signal. US Patent No. 11,499,916 (Patent Document 1) discloses a spectroscopic system in which a thermal desorption tube is provided before the ring-down cavity. This thermal desorption tube contains an adsorbent capable of desorbing a target compound from the gas by heating. In this spectroscopic system, the target compound is concentrated in the thermal desorption tube and then sent to the ring-down cavity for detection.

[0003] Existing technical documents Patent documents Patent Document 1: US Patent No. 11499916 Summary of the Invention The technical problem that the invention aims to solve However, in the spectroscopic system of Patent Document 1, the use of a structure connecting the thermal desorption tube and the ring-down chamber via piping creates a dead volume, causing the target compound concentrated by the adsorbent to be diluted again. Therefore, this dilution leads to a decrease in the detection sensitivity of the target component. Furthermore, in the spectroscopic system of Patent Document 1, the gas delivery requires time due to the aforementioned structure connecting the thermal desorption tube and the ring-down chamber via piping, resulting in a longer measurement time. This presents a particular technical problem in measuring low-concentration gases with short measurement cycles.

[0004] This disclosure was made to solve the above-mentioned technical problems, and its purpose is to provide a detection device that can detect target components in a gas in a short time and with high sensitivity.

[0005] Solution to the above technical problems A first aspect of the present invention is a detection device comprising: a first gas chamber, a first adsorbent, a first stimulation unit, a first light source, a first detector, and a measuring unit. Gas is introduced into the first gas chamber. The first adsorbent is disposed in the first gas chamber such that it forms a first unfilled space inside the first gas chamber, and adsorbs a first target component in the gas. The first unfilled space is a space where the first adsorbent is not filled. The first stimulation unit stimulates the first adsorbent, causing the first target component to detach into the first unfilled space. The first light source illuminates the first unfilled space. The first detector detects the light emitted from the first gas chamber. The measuring unit detects the first target component based on the output of the first detector.

[0006] A second aspect of the present invention is a detection method comprising the steps of: introducing a gas containing a target component to be detected into a gas chamber, the gas chamber being filled with an adsorbent that adsorbs the target component in such a way that an unfilled space is formed inside. The unfilled space is the space where no adsorbent is filled. The detection method further comprises: applying a stimulus to the adsorbent to cause the target component to detach into the unfilled space; irradiating the unfilled space with light; detecting the light emitted from the gas chamber using a detector; and measuring the target component based on the output from the detector.

[0007] Invention Effects According to this disclosure, a detection device can be provided that can detect target components in a gas with high sensitivity in a short time. Attached Figure Description

[0008] [ Figure 1 [Illustration 1] is a schematic diagram showing the structure of the detection device according to Embodiment 1.

[0009] [ Figure 2 [This is a flowchart illustrating the detection and processing of target components in a gas.]

[0010] [ Figure 3 [ ] is a diagram showing one stage of the detection of target components in a gas.

[0011] [ Figure 4 [ ] is a diagram showing one stage of the detection of target components in a gas.

[0012] [ Figure 5 [ ] is a diagram showing one stage of the detection of target components in a gas.

[0013] [ Figure 6 [ ] is a diagram showing one stage of the detection of target components in a gas.

[0014] [ Figure 7 [Illustration 1] is a schematic diagram showing the structure of the detection device involved in the modified example 1.

[0015] [ Figure 8[Illustration 1] is a schematic diagram showing the structure of the detection device involved in Modification 2.

[0016] [ Figure 9 [Illustration 1] is a schematic diagram showing the structure of the detection device involved in Modification 3.

[0017] [ Figure 10 [Illustration 4] is a schematic diagram showing the structure of the detection device involved in the modified example 4.

[0018] [ Figure 11 [ ] is a diagram illustrating the structure of the detection device involved in Embodiment 2.

[0019] [ Figure 12 [ ] is a diagram illustrating the structure of the air chamber involved in Embodiment 2 when viewed from the light source side.

[0020] [ Figure 13 [] is a table used to explain the settings of the detection device involved in Embodiment 2. Detailed Implementation

[0021] Hereinafter, embodiments of the present invention will be described in detail with reference to the accompanying drawings. Furthermore, identical or equivalent parts in the drawings are labeled with the same symbols, and their descriptions will not be repeated.

[0022] [1. Structure of the detection device] Figure 1 This is a schematic diagram illustrating the structure of a detection device 100 according to an embodiment of the present invention. The detection device 100 detects a target component in a gas introduced from the outside. In one embodiment, the detection device 100 measures the concentration of the target component in the gas. In another embodiment, the detection device 100 is used to detect the presence or absence of the target component in the gas. Furthermore, in this specification, the target component refers to the target substance detected in the detection device 100.

[0023] exist Figure 1 In the example, a portion of the gas in gas piping 8 is introduced into detection device 100 through piping 63. Detection device 100 includes detection unit 101 and control device 102.

[0024] The detection unit 101 includes a gas chamber 1, an adsorbent 2, a stimulation unit 3, a light source 4, a detector 5, valves 61 and 62, and piping 63 and 64. The gas chamber 1, adsorbent 2, stimulation unit 3, light source 4, and detector 5 correspond to one embodiment of "first gas chamber," "first adsorbent," "first stimulation unit," "first light source," and "first detector," respectively. The target component adsorbed by the adsorbent 2 corresponds to one embodiment of "first target component."

[0025] Gas piping 8 is a piping through which the test gas, which may contain the target component, passes. In one embodiment, the test gas comprises a base gas as the main component and a target component as the detection target. The base gas is, for example, carbon dioxide. However, the base gas may also contain various types of gases. Figure 1 The target components in chamber 1 are then represented by Figure 9.

[0026] Pipe 63 connects gas pipe 8 and gas chamber 1. Pipe 63 is used to introduce a portion of the gas from gas pipe 8 into gas chamber 1. A valve 61 is provided on pipe 63. Valve 61 regulates the introduction of gas into gas chamber 1. Valve 61 corresponds to one embodiment of the "introduction opening and closing part". Pipe 64 is used to discharge gas discharged from gas chamber 1 to the outside. In one embodiment, one end of pipe 64 is connected to gas chamber 1, and the other end is open to the atmosphere. A valve 62 is provided on pipe 64. Valve 62 regulates the discharge of gas from gas chamber 1. Valve 62 corresponds to one embodiment of the "discharge opening and closing part". As configured as described above, the inlet for introducing gas and the outlet for discharging gas in gas chamber 1 are different, and the introduction and discharge of gas can be easily controlled. Therefore, by allowing gas to pass through gas chamber 1, the adsorbent 2 can easily and efficiently adsorb the target component.

[0027] For the purpose of further explanation, Figure 1 In the example, the direction of gas flow in pipes 63 and 64 is defined as the positive X-axis, the direction parallel to the central axis AX of light passing through gas chamber 1 is defined as the negative Z-axis, and the direction perpendicular to the XZ plane is defined as the Y-axis. Furthermore, the direction of gas flow in pipes 63 and 64 does not necessarily have to be perpendicular to the central axis AX of light passing through gas chamber 1, and the negative Z-axis does not necessarily have to be the direction of gravity.

[0028] Gas is introduced into gas chamber 1 through gas pipe 8. Inside gas chamber 1, adsorbent 2 is configured to fill unfilled spaces 19. When the gas introduced into gas chamber 1 contains the target component, the target component is adsorbed by adsorbent 2.

[0029] More specifically, the air chamber 1 includes a pair of optical windows 131, 132 and a housing 14. An inlet 11 and an outlet 12 are formed on the housing 14.

[0030] The inlet 11 is connected to the piping 63. In one embodiment, when the valve 61 is opened, gas from the gas piping 8 is introduced into the gas chamber 1 through the inlet 11.

[0031] The outlet 12 is connected to the piping 64. In one embodiment, when the valve 62 is opened, the gas in the gas chamber 1 is discharged from the outlet 12.

[0032] The housing 14 supports the overall structure of the gas chamber 1. Therefore, the housing 14 is formed of a material with sufficient rigidity to support the overall structure of the gas chamber 1. The housing 14 may contain, for example, metal or ceramic. As described later, when the adsorbent 2 has the property of detaching the target component by applying heat, the housing 14 is preferably formed of a material with high thermal conductivity. This high thermal conductivity material is, for example, metal or high thermal conductivity ceramic.

[0033] A pair of optical windows 131 and 132 are window materials that are respectively embedded in two opposing holes formed on the housing 14.

[0034] The adsorbent 2 is configured to form an unfilled space 19 inside the gas chamber 1. In this specification, the unfilled space 19 is the space within the gas chamber 1 where the adsorbent 2 is not filled. By configuring the adsorbent 2 to form an unfilled space 19 inside the gas chamber 1, an optical path can be formed within this unfilled space 19. Figure 1 In the example, the unfilled space 19 is the space between the optical windows 131 and 132 inside the housing 14 where the adsorbent 2 is not disposed. Furthermore, an optical path 45 is formed in this unfilled space 19. The unfilled space 19 corresponds to one embodiment of the "first unfilled space".

[0035] Light source 4 illuminates light into gas chamber 1. More specifically, light source 4 is positioned to illuminate unfilled space 19. Light source 4 is, for example, a laser light source. Figure 1 In the example, light emitted from light source 4 is reflected by one or more mirrors (not shown) and shines into the unfilled space 19 through optical window 131. However, it is also possible to configure the light emitted from light source 4 to shine directly into the unfilled space 19 without passing through a mirror.

[0036] Detector 5 is positioned to detect light emitted from gas chamber 1. Detector 5 detects the target component in the gas by detecting light that has passed through the gas in gas chamber 1 and exited into the unfilled space 19. Detector 5 can be, for example, a photodiode, an image sensor, or other photodetector. Figure 1 In the example, light emitted from the unfilled space 19 is incident on the detector 5 through the optical window 132. A detection signal showing the detection result of the detector 5 is sent to the control device 102.

[0037] By configuring the light source 4 and detector 5 as described above, an optical path 45 is formed in the unfilled space 19, allowing light to pass from the light source 4 to the detector 5.

[0038] Preferably, the gas chamber 1 has an optical resonator structure. An optical resonator structure, also known as a multiple reflection structure or multipath optical system, is a structure that confines light between facing mirrors and allows light to travel back and forth multiple times. For example, mirrors that reflect most of the received light are used as optical windows 131 and 132. Thus, by having light travel back and forth multiple times in the unfilled space 19, the distance the light travels through the gas (equivalent optical path length) can be increased. The detector 5 uses the light leaking from the optical window 132 as detection light. With the above structure, the light absorption of the target component in the unfilled space 19 can be amplified and detected. Therefore, the detection sensitivity of the target component can be improved.

[0039] In the absence of an optical resonator structure in the air chamber 1, window materials containing glass, resin, etc., that allow most of the light to pass through can be used as optical windows 131, 132.

[0040] Adsorbent 2 adsorbs the target component in the gas. This increases the concentration of the target component within the (concentrated) gas chamber 1. Adsorbent 2 has the property of detaching the adsorbed target component when a predetermined stimulus is applied. This allows the gas chamber 1 to be filled with gas containing the concentrated target component. Therefore, even when the target component in the gas pipe 8 is present in trace amounts, the concentrated target component in the gas chamber 1 can be detected. In particular, by placing adsorbent 2 within the gas chamber 1, the volume of space between the target component detached from adsorbent 2 and the detection position (unfilled space 19) can be minimized. This suppresses the dilution of the concentrated target component, enabling highly sensitive detection of the target component. Furthermore, since the transport path between the target component detached from adsorbent 2 and the detection position (unfilled space 19) can be minimized, short-time detection of the target component is possible (see later description).

[0041] In one embodiment, adsorbent 2 is a Mg-gallate that adsorbs sulfur dioxide, and detection device 100 detects sulfur dioxide in carbon dioxide. In another embodiment, adsorbent 2 is an fcu-MOF that adsorbs ammonia, and detection device 100 detects ammonia in carbon dioxide. Adsorbent 2 is disposed inside gas chamber 1. In one embodiment, adsorbent 2 is supported on a carrier within gas chamber 1. For example, adsorbent 2 is configured to cover the surface of the carrier. Figure 1 In the diagram, the portion indicated by reference numeral 2 includes a carrier. In another embodiment, the adsorbent 2 is supported on the inner wall 141 of the gas chamber 1. In this case, the inner wall 141 is the carrier of the adsorbent 2. The carrier of the adsorbent 2 may, for example, contain metal or ceramic.

[0042] exist Figure 1In the example, adsorbent 2 includes adsorbent 21 disposed on the inlet 11 side and adsorbent 22 disposed on the outlet 12 side. This configuration allows all gas flowing into the gas chamber 1 to pass through adsorbent 21 and all gas exiting the gas chamber 1 to pass through adsorbent 22. Therefore, compared to the case where the gas chamber 1 contains only one of adsorbents 21 and 22, the target component can be more easily adsorbed by the adsorbent. Furthermore, compared to the case where adsorbents 21 and 22 are arranged parallel to each other along the gas flow direction in the gas chamber 1, the target component can be more easily adsorbed by the adsorbent. By making the target component more easily adsorbed by the adsorbent, the amount of the target component adsorbed by the adsorbent per unit time increases. Therefore, detection in a shorter time and / or with higher sensitivity can be achieved.

[0043] The adsorbent 2 preferably has a honeycomb structure or a finned structure. In one embodiment, the adsorbent 2 is supported on the surface of a carrier having a honeycomb or finned structure. This configuration easily increases the surface area of ​​the adsorbent 2, thereby increasing the adsorption amount of the free target component in the gas. Therefore, the concentration of the target component within the gas chamber 1 can be further increased. More preferably, the gas within the gas chamber 1 is configured to pass through at least a portion of the aforementioned honeycomb or finned structure. This makes it easier for the target component in the gas to be adsorbed by the adsorbent 2. Therefore, the concentration of the target component within the gas chamber 1 can be further increased. Figure 1 In the example, for instance, the adsorbents 21 and 22 are configured such that the pores of the honeycomb structure or the gaps of the finned structure are aligned parallel to the X-axis. This allows gas introduced from the inlet 11 to pass through the pores of the honeycomb structure or the gaps of the finned structure of the adsorbent 21 and then into the unfilled space 19. Furthermore, the gas introduced into the unfilled space 19 can pass through the pores of the honeycomb structure or the gaps of the finned structure of the adsorbent 22 and then exit from the outlet 12. With the structure described above, the target component can be more easily adsorbed by the adsorbent 2. Therefore, detection in a shorter time and / or with higher sensitivity can be achieved.

[0044] Preferably, the adsorbent 2 is configured to detach from the gas chamber 1. This facilitates the replacement of the adsorbent 2. Therefore, it is easy to replace the adsorbent 2 that has deteriorated due to repeated use. Furthermore, by replacing it with an adsorbent 2 that adsorbs different target components, the gas chamber 1 can be reformulated to detect different target components.

[0045] The stimulation section 3 applies a stimulus to the adsorbent 2, causing the target component to detach into the unfilled space 19. The type of stimulus applied by the stimulation section 3 to detach the target component depends on the type of adsorbent 2. According to one embodiment, the stimulation section 3 detaches the target component from the adsorbent 2 by microwave heating or heater heating. This allows for easy control of both the detachment of the target component from the adsorbent 2 and its adsorption into the adsorbent 2. Preferably, the stimulation section 3 heats the adsorbent 2 in a manner that generates a temperature gradient within the gas chamber 1. Figure 1 In one example, the adsorbents 21 and 22 are heated at the same set temperature, thereby lowering the temperature in the central part of the unfilled space 19 compared to the vicinity of the adsorbents 21 and 22. Alternatively, in another example, the set temperature of the adsorbent 21 on the inlet 11 side can be higher than the set temperature of the adsorbent 22 on the outlet 12 side, resulting in a higher temperature on the inlet 11 side and a lower temperature on the outlet 12 side. By creating a temperature gradient within the gas chamber 1 in this way, convection is generated within the gas chamber 1, promoting the diffusion of the detached target gas. As a combination of the stimulation section 3 and the adsorbent 2, a combination with the following characteristics can also be used: the adsorbent 2 is stimulated by light, a magnetic field, or the like by the stimulation section 3, causing the adsorbent 2 to detach the target component.

[0046] The control device 102 includes processors such as CPU (Central Processing Unit) and FPGA (Field-Programmable Gate Array) 103, as well as memory such as ROM (Read Only Memory) and RAM (Random Access Memory) 104 and input / output ports (not shown).

[0047] The control device 102 controls the detection unit 101. The control device 102 corresponds to one embodiment of a "measuring unit" that measures the target component based on the output of the detector 5. Specifically, the control device 102 performs various data processing operations to calculate the concentration of the target component contained in the gas based on the detection signal from the detector 5.

[0048] Furthermore, the control device 102 may also be configured by dividing it into two or more units according to its functions. For example, the control device 102 may be divided into a unit for controlling various devices and a unit for performing various data processing.

[0049] [2. Testing Process] Figure 2 This is a flowchart illustrating the process for detecting and processing target components in a gas. Figures 3-6 This is a diagram illustrating the various stages of target component detection in a gas. The following will refer to... Figures 3-6 illustrate Figure 2 The processing. Figure 2 The processing is performed by processor 103.

[0050] Reference Figure 2 In ST01, processor 103 introduces a gas containing the target component to be detected into gas chamber 1, which is filled with adsorbent 2 in such a way that it forms unfilled spaces 19. In one embodiment, in ST01, processor 103 introduces gas from gas piping 8 into gas chamber 1 by opening valves 61, 62 before and after the gas chamber, and discharges the gas through gas chamber 1 to the outside. Thus, the target component is adsorbed by the adsorbent 2 disposed inside gas chamber 1 (see reference). Figure 3 By continuously introducing gas into gas chamber 1, the adsorption amount of the target component onto adsorbent 2 continuously increases. As described above, through the accumulation of the adsorbed amount of the target component, the target component is concentrated within gas chamber 1 (see reference). Figure 4 ).

[0051] In ST02, the processor 103 stops introducing gas into the gas chamber 1 after a predetermined time has elapsed since the gas introduction began. This predetermined time is preferably shorter than the breakthrough time pre-designed based on the specifications of the gas chamber 1. With this design, the target component will not reach saturation, thus allowing for appropriate concentration measurement. Furthermore, the gas discharged from the gas chamber 1 does not contain the target component. Therefore, even if the target component is a harmful substance, it will not pollute the atmosphere. The predetermined time for introducing gas into the gas chamber 1 can be determined based on an estimated concentration of the target component in the gas chamber 1. For example, if the gas in the gas piping 8 contains the target component, the predetermined time for introducing the gas can be taken as the time required to reach a concentration at which the target component can be detected in the detector 5.

[0052] In one embodiment, in ST02, processor 103 sets valves 61, 62 to the closed state (see reference). Figure 5 Thus, chamber 1 becomes a closed space. Therefore, the concentration of the target component within chamber 1 stops. Thus, even if the target component is removed from adsorbent 2, it will not leak to the outside of chamber 1.

[0053] In ST03, processor 103 applies stimulation to adsorbent 2 via stimulation section 3. This allows the target component to detach from adsorbent 2 into unfilled space 19. The detached target component diffuses within unfilled space 19 (see reference). Figure 6 ).exist Figure 6 In the example, the target component in the adsorbent 2 state is represented by figure 91, and the target component in the gas that has been removed from the adsorbent 2 is represented by figure 92.

[0054] After the adsorbent 2 is stimulated at a predetermined intensity for a predetermined time, in ST04, the processor 103 controls the light source 4 to irradiate light into the unfilled space 19 in the gas chamber 1. Preferably, the intensity and duration of the stimulation applied to the adsorbent 2 before irradiating the gas chamber 1 are set such that light is irradiated after the target component has fully detached from the adsorbent 2 and a steady state has been reached in the gas chamber 1.

[0055] In ST05, processor 103 detects the light emitted from gas chamber 1. Figure 6 In the example, detector 5 detects transmitted light emitted from gas chamber 1. Processor 103 receives a detection signal from detector 5. More specifically, since the target component absorbs a predetermined light component in the unfilled space 19, this light component attenuates from the incident light by a corresponding amount according to the concentration of the target component. Processor 103 receives a detection signal indicating this attenuation. Furthermore, in ST05, detector 5 can also be configured to detect reflected light emitted from gas chamber 1. More specifically, detector 5 can also detect scattered light generated by Raman scattering and detect the light component contained in the scattered light.

[0056] In ST06 to ST07, the processor 103 measures the target component based on the output from the detector 5. An embodiment of ST06 to ST07 is described below.

[0057] In ST06, processor 103 measures the concentration of the target component in the gas within gas chamber 1 from the aforementioned detection signal. Figure 6 In the example, the target component concentration of the gas in the unfilled space 19 is measured as the target component concentration in the gas chamber 1.

[0058] In ST07, processor 103 calculates the concentration of the target component contained in the gas in gas piping 8 from the target component concentration in gas chamber 1. For example, processor 103 calculates the target component concentration in gas piping 8 based on the target component concentration in gas chamber 1 measured in ST06 and the volume of gas passing through gas chamber 1. For example, when the time for introducing gas into gas chamber 1 is shorter than the breakthrough time, and it is considered that all target components have been removed from adsorbent 2 by stimulation of stimulation section 3, the target component concentration in gas piping 8 is the value obtained by dividing the amount of target component in gas chamber 1 by the volume of gas passing through gas chamber 1. The amount of target component in gas chamber 1 is the product of the gas chamber volume and the gas chamber concentration. The volume of gas passing through gas chamber 1 is, for example, the product of the gas flow rate in gas chamber 1 (the volume of gas moving per unit time) and the length of time for introducing gas into gas chamber 1. The gas flow rate in gas chamber 1 is, for example, obtained by installing a flow sensor (not shown) on piping 63 and based on the detection value of the flow sensor.

[0059] In ST08, processor 103 discharges the gas containing the target component concentrated in gas chamber 1. In one embodiment, in ST08, processor 103 opens valves 61 and 62 before and after the gas chamber. This allows gas from gas piping 8 to be introduced into gas chamber 1, and the gas containing the target component concentrated in gas chamber 1 is discharged.

[0060] In ST08, after the gas in gas chamber 1 is discharged and a predetermined time has elapsed, in ST09, processor 103 stops the stimulation of adsorbent 2 by stimulation unit 3. This predetermined time is set longer than the time required to presumably discharge the gas containing the target component concentrated in gas chamber 1. For example, regarding ST09, stimulation of stimulation unit 3 may also be stopped after confirming that the concentration of the target component detected by detector 5 is sufficiently low, as light transmitted from light source 4 is observed. More specifically, stimulation may be stopped a few seconds after the concentration of the target component in gas chamber 1 reaches below the detection limit. The steps from ST03 to ST09 constitute one cycle of target component detection.

[0061] In ST10, processor 103 determines whether the termination condition for target component detection is met. An example of this termination condition is receiving an instruction from the user to end the detection. Another example is, for instance, completing a predetermined number of detection cycles.

[0062] When the termination condition is not met ("No" in ST10), the processor 103 returns processing to ST01. Then, the next detection cycle begins. Furthermore, in ST01 of the second and subsequent cycles, if valves 61 and 62 were already in the open state in ST08 of the previous cycle, the processor 103 only needs to maintain the open state of valves 61 and 62.

[0063] On the other hand, when the termination condition is met ("Yes" in ST10), the processor 103 terminates the processing.

[0064] According to usage Figures 1-6 The described detection apparatus 100 or detection method, because the adsorbent 2 is configured to form an unfilled space 19 within the gas chamber 1, allows for detection of the target component concentrated by the adsorbent 2 without dilution. For example, in the spectroscopic system of Patent Document 1, the gas to be tested is introduced into a thermal desorption tube to concentrate the target compound, and the gas containing the concentrated target compound is detected using a laser. Thus, in the spectroscopic system of Patent Document 1, the target component can be detected with high sensitivity compared to apparatuses without a concentration section.

[0065] However, in the spectroscopic system of Patent Document 1, a dead volume is generated because the thermal desorption tube and the ring-down chamber are connected by piping. Furthermore, in this specification, dead volume refers to the volume of the concentrated target component that is diluted before detection (e.g., the portion including the piping described in Patent Document 1) within the volume from the concentrated target component to the detected component. In the spectroscopic system of Patent Document 1, the concentrated target component is diluted due to this dead volume. Additionally, the target component is also diluted when it adheres to the wall or other surfaces of the gas piping 8.

[0066] On the other hand, in the detection device 100, by integrating the portion containing the adsorbent 2 with the gas chamber 1, the dead volume can be minimized. This suppresses dilution of the detached gas. Therefore, more sensitive detection of the target component is possible.

[0067] Furthermore, the detection device 100 can directly measure the target component detached from the adsorbent 2 within the gas chamber 1. For example, in the spectroscopic system of Patent Document 1, there is a technical problem of prolonged measurement time because it takes time to transport the target component detached from the pyrolysis tube through the piping to the decay chamber. However, in the detection device 100, since the adsorbent 2 adsorbing the target component is adjacent to the unfilled space 19 for detecting the target component, the time for transporting the detached gas to the gas chamber can be reduced. Thus, the target component can be detected in a short time in the detection device 100. Therefore, it is suitable for continuously monitoring the presence and / or concentration of the target component in the gas piping 8. As described above, it can be said that the detection device 100 and detection method according to this embodiment are detection devices and detection methods capable of detecting target components in gas with short time and high sensitivity. Therefore, low concentrations of target components can be detected in a short detection cycle.

[0068] [3. Variations] Figures 7-10 Examples 1 to 4 of the detection device 100 according to the above embodiments are shown.

[0069] Figure 7 This is a schematic diagram showing the structure of the detection device involved in Modified Example 1. Figure 7 The testing department 101A is in Figure 1 Based on the structure of the detection unit 101, a cooler 71 is also included. After measuring the concentration of the target component in the gas chamber 1, the cooler 71 cools the adsorbent 2 heated by the stimulation unit 3. This shortens the time required for the adsorbent 2 to re-adsorb the target component. Therefore, since the time required for one detection cycle can be shortened, the detection cycle can be accelerated. Figure 7 In the example, cooler 71 indirectly cools adsorbent 2 by cooling the high thermal conductivity shell 14F, but it can also directly cool adsorbent 2.

[0070] Figure 8 This is a diagram showing the structure of the detection device involved in Modification Example 2. Figure 7 The testing department 101B is in Figure 1 Based on the structure of the detection unit 101, it also includes light sources 721 and 722, detectors 723 and 724, and optical windows 725 to 728. Light sources 721 and 722 illuminate adsorbents 21 and 22 respectively. Detectors 723 and 724 detect target components adsorbed on each adsorbent 21 and 22 based on the emitted light from each adsorbent 21 and 22. For example, detectors 723 and 724 detect transmitted or scattered light from each adsorbent 21 and 22. Optical windows 725 and 726 are respectively disposed between the light sources 721 and 722 and the adsorbents 21 and 22. Optical windows 727 and 728 are respectively disposed between the adsorbents 21 and 22 and the detectors 723 and 724. Light generated by the light sources 721 and 722 is incident on the adsorbents 21 and 22 through optical windows 725 and 726 respectively. The emitted light from adsorbents 21 and 22 is incident on detector 5 through optical windows 727 and 728, respectively.

[0071] The detection signals of the emitted light from detectors 723 and 724 are sent to control device 102, which detects the target component adsorbed on adsorbents 21 and 22 based on these detection signals. Control device 102 measures the concentration of the target component, for example, based on the spectral changes of transmitted light relative to incident light and the spectral changes of reflected light relative to incident light. In the detection device according to Modification 2, after stimulation of adsorbents 21 and 22 by stimulation unit 3, even if a portion of the target component remains in adsorbents 21 and 22, the concentration of the remaining target component can be measured. Therefore, compared to measuring only the concentration of the target component in the gas, the concentration of the target component in gas chamber 1 can be determined more accurately. Therefore, the concentration of the target component in gas piping 8 can be determined with higher accuracy. Therefore, according to detection unit 101B, the monitoring of the target component can be performed more accurately.

[0072] Figure 9 This is a diagram showing the structure of the detection device involved in Modified Example 3. Figure 9 The testing department 101C is in Figure 1 Based on the structure of the detection unit 101, it also includes a separation unit 73. The separation unit 73 is located in the pre-stage of the gas chamber 1. Figure 9In the example, the separation unit 73 is installed between the valve 61 and the gas chamber 1 of the piping 63. The separation unit 73 separates a specific component from the gas introduced from the gas piping 8. Thus, the specific component can be removed before the gas is introduced into the gas chamber 1. The separation unit 73, for example, contains an adsorbent that adsorbs the specific component. The specific component is a component contained in the gas in the gas piping 8 that is different from the target component. The specific component is, for example, a substance that is not needed for measuring the target component or would hinder it. Therefore, according to the detection unit 101C, even when the gas in the gas piping 8 contains a substance that is not needed for measuring the target component or would hinder it, the target component can be accurately measured.

[0073] Figure 10 This is a diagram showing the structure of the detection device involved in Modification Example 4. Figure 10 The detection device involved in the modified example 4 described in the text, in addition to having the same... Figure 1 In addition to the detection unit 101D, which has the same structure as the detection unit 101, there is also a detection unit 101E.

[0074] The detection unit 101E includes a gas chamber 1E, an adsorbent 2E, a stimulation unit 3E, a light source 4E, a detector 5E, valves 61E and 62E, and piping 63E and 64E. The gas chamber 1E, adsorbent 2E, stimulation unit 3E, light source 4E, detector 5E, and unfilled space 19E correspond to one embodiment of the "second gas chamber," "second adsorbent," "second stimulation unit," "second light source," "second detector," and "second unfilled space," respectively. The target component adsorbed by the adsorbent 2E (represented by figure 9E) corresponds to one embodiment of the "second target component."

[0075] The target component adsorbed by adsorbent 2E is different from the target component adsorbed by adsorbent 2. Therefore, in detection unit 101E, a target component different from that in detection unit 101 can be detected. Thus, according to the detection device according to Modified Example 4, multiple target components in gas piping 8 can be monitored simultaneously.

[0076] [4. Implementation Method 2] exist Figures 11-13 The following describes the detection device according to Embodiment 2. The difference between the detection device according to Embodiment 2 and the detection device 100 according to Embodiment 1 is that the structure of the detection unit 101F is different from the structure of the detection unit 101.

[0077] Figure 11 This is a diagram illustrating the structure of the detection device involved in Embodiment 2. Figure 11 The description of the light source 4 and detector 5 of the detection unit 101F is omitted, and the structure of the gas chamber 1F is shown by its cross-sectional view. Figure 12 This is a diagram illustrating the structure of air chamber 1F when viewed from the light source 4 side (positive Z-axis direction side).

[0078] The difference between detection unit 101F and detection unit 101 lies in the structure of gas chamber 1F and the structure of adsorbent 2F. In addition, the difference between detection unit 101F and detection unit 101 lies in the presence of heat insulation materials 65F and 66F before and after gas chamber 1F. Figure 11 and Figure 12 The gas flow in the diagram is represented by arrows AR1 to AR4.

[0079] The insulation materials 65F and 66F insulate the air chamber 1F from the outside. Thus, even when the temperature of air chamber 1 is higher or lower than the outside temperature, heat conduction to or from the outside can be suppressed.

[0080] The gas chamber 1F includes a pair of optical windows 131F and 132F and a housing 14F. A generally cylindrical inner hole 15F is formed in the housing 14F. Adsorbent 2F is filled in the inner hole 15F in a manner that forms an unfilled space 19F.

[0081] In one embodiment, adsorbent 2F is supported within gas chamber 1F in a state of being supported on a carrier. For example, adsorbent 2F is configured to cover the surface of the carrier. Figure 11 In the diagram, the portion indicated by label 2F contains the carrier.

[0082] The adsorbent 2F is cylindrical in shape. However, the internal structure of the adsorbent 2 is preferably a honeycomb structure or a finned structure, with gaps arranged along the direction of gas flow (as indicated by arrow AR2). This allows the gas introduced from the inlet 11F (refer to arrow AR1) to easily pass through the holes of the honeycomb structure or the gaps of the finned structure (refer to arrow AR2).

[0083] An inner hole 15F has a recess near its center along the Z-axis. A space 16F is formed between this recess and the adsorbent 2F. Thus, gas that has passed through the adsorbent 2F as shown by arrow AR2 can exit from the outlet 12F after passing through the space 16F as shown by arrow AR3.

[0084] As described above, the structure of the gas chamber 1F and adsorbent 2F in Embodiment 2 promotes the adsorption of the target component by allowing gas to pass through the entire adsorbent 2F. This increases the concentration of the target component within the gas chamber 1F.

[0085] More specifically, as long as the adsorption capacity is unsaturated, the adsorption capacity of the target component on the adsorbent increases with the increase of the contact area between the gas and the adsorbent, and also with the increase of the contact time. Furthermore, it naturally increases with the increase of the amount of gas passing through the adsorbent. In Embodiment 2, in addition to the structure that increases the chance of gas passing through the adsorbent ( Figure 11In addition, the concentration of the target component in gas chamber 1F can be increased by setting the internal volume (capacity) of gas chamber 1, the volume of the adsorbent, the gas flow rate, and the concentration time of the target component in the gas.

[0086] Figure 13 This is a table used to explain the settings of the detection device according to Embodiment 2. In Embodiment 2, by reducing the volume of the gas chamber 1F, the target component can be easily concentrated to the concentration required for detection, and short-time measurement is possible. Furthermore, the volume of the gas chamber 1F is preferably calculated including the dead volume of valves, etc. The volume of the gas chamber 1F is, for example, 1000 mm². 3 Furthermore, in the aforementioned small gas chamber 1F, a large amount of adsorbent 2F is provided to fill all spaces except for the unfilled space 19F for light transmission and the space 16F for gas diffusion. The volume of the adsorbent 2F is, for example, 500 mm³. 3 With this structure, by increasing the volume ratio of the gas chamber 1F to the adsorbent 2F, the concentration of the target component within the gas chamber 1F can be further increased in a short time. This volume ratio is, for example, approximately 0.5.

[0087] The gas flow rate (gas flow rate) through gas chamber 1F is set such that the gas passes through the adsorbent 2 at an appropriate velocity within gas chamber 1. For example, the gas flow rate is 1.5 L / mm.

[0088] Furthermore, by heating and cooling the gas chamber 1F using the stimulation part 3F and the cooler 71F, the temperature within the gas chamber 1F can be rapidly switched from high temperature to low temperature and from low temperature to high temperature. The stimulation part 3F is, for example, a heater and / or a Peltier element. The cooler 71F is, for example, a Peltier element. Thus, for example, a set temperature above room temperature and below 200°C can be set, and the temperature within the gas chamber 1F can be adjusted to be above room temperature and below 200°C. In one embodiment, the set temperature is set to two stages: the temperature at which the target component is easily adsorbed by the adsorbent 2F (adsorption temperature) and the temperature at which the target component is easily removed from the adsorbent 2F (removal temperature). The adsorption temperature and the removal temperature are, for example, room temperature and 200°C, respectively. The heating from the adsorption temperature to the removal temperature is, for example, performed in 2 seconds. The cooling from the removal temperature to the adsorption temperature is, for example, performed in 8 seconds.

[0089] The pressure (internal pressure) within chamber 1F is set to a pressure that does not impede the adsorption process of the target component to adsorbent 2F, the temperature rise process within chamber 1F, and the detachment process of the target component from adsorbent 2F, and / or is suitable for each process. For example, the internal pressure during adsorption is 200 kPa, the internal pressure during temperature rise is 315 kPa, and the internal pressure during detachment is 315 kPa.

[0090] The structure and configuration of the gas chamber 1F described above can shorten the time for concentrating the target component in the gas (concentration time) and the time for measuring the concentration of the target component in the gas. The concentration time is the time during which the target component in the gas is adsorbed onto the adsorbent 2F. For example, the concentration time is 40 seconds, and the measurement time is 40 seconds.

[0091] Examples of target components to be detected include, but are not limited to, NH3, NO, N2O, NO3, HCN, H2S, SO2, and SO3. The Gas Cell 1F can detect these target components with short time and high sensitivity. The detection limit is, for example, 10 ppb.

[0092] The optical path length D1 in the gas chamber 1F is set to a length sufficient for detection. The optical path length D1 is, for example, approximately 10.5 mm. In one embodiment, in the gas chamber 1F, light incident from the optical window 131F passes through a range 763 sandwiched between dashed lines 761 and 762, and exits from the optical window 132F. The central axis of the range 763 is indicated by the dotted line AXF. Alternatively, the unfilled space 19F between the optical windows 131F and 132F can be configured as a resonator.

[0093] also, Figure 13 The numerical examples provided are merely examples and may be appropriately modified within the scope of producing the effects of this implementation.

[0094] The detection process in the detection device involved in Embodiment 2 is the same as... Figure 2 The flowchart shown is the same. As a summary, in Embodiment 2, the processor 103 also opens valves 61F and 62F, causing the target component to be adsorbed onto the adsorbent 2F. Next, valves 61F and 62F are closed, and the target component is detached from the adsorbent 2 to the unfilled space 19F via the stimulation section 3F. Then, light is irradiated into the unfilled space 19F from the light source 4, forming a light path 45F. Based on the detection signal from the detector 5 that detects the light emitted from the gas chamber 1F, the concentration of the target component in the gas chamber 1F is calculated, and the concentration of the target component in the gas pipe 8 is also calculated. Afterward, valves 61F and 62F are opened, allowing gas from the gas pipe 8 to flow, purging the gas containing the concentrated target component from the adsorbent 2F from the gas chamber 1F. After the gas containing the concentrated target component is discharged from the gas chamber 1F, the stimulation of the adsorbent 2F by the stimulation section 3F is stopped, and / or cooling of the cooler 71F begins. When the adsorbent 2F returns to the state before stimulation by the stimulation part 3F, if the user does not give an instruction to end the measurement, the adsorption process of the target component for the next measurement will begin.

[0095] According to the detection apparatus and method described above in the embodiments and modifications, trace target components contained in a test gas can be detected with high sensitivity and in a short time. By using this technology to measure the concentration of a predetermined gaseous component contained in a test gas with high sensitivity, the proportion of gaseous components contained in the raw material gas used in a chemical process can be analyzed, and / or the chemical reaction state in the chemical process can be analyzed. More specifically, in chemical plants and their research and development sites, trace impurity gases contained in raw material gases can be analyzed.

[0096] [plan] Those skilled in the art should understand that the above-described exemplary embodiments are specific examples of the following solutions.

[0097] (Item 1) A detection device according to one embodiment includes: a first gas chamber, a first adsorbent, a first stimulating unit, a first light source, a first detector, and a measuring unit. Gas is introduced into the first gas chamber. The first adsorbent is disposed in the first gas chamber in such a way that it forms a first unfilled space inside the first gas chamber, and adsorbs a first target component in the gas. The first unfilled space is a space where the first adsorbent is not filled. The first stimulating unit stimulates the first adsorbent, causing the first target component to detach into the first unfilled space. The first light source illuminates the first unfilled space. The first detector detects the light emitted from the first gas chamber. The measuring unit detects the first target component based on the output of the first detector.

[0098] According to the detection apparatus described in claim 1, by disposing the adsorbent in the gas chamber, the spatial volume between the target component detached from the adsorbent and the detection position can be minimized. This suppresses the dilution of the concentrated target component, thus enabling highly sensitive detection of the target component. Furthermore, since the transport path between the target component detached from the adsorbent and the detection position can be minimized, short-time detection of the target component is possible. As described above, a detection apparatus capable of detecting a target component in a gas with short-time and high sensitivity can be provided.

[0099] (Item 2) The detection device described in Item 1 further comprises: an inlet opening and closing section for regulating the introduction of gas into the first gas chamber; and an outlet opening and closing section for regulating the discharge of gas from the first gas chamber.

[0100] According to the detection device described in item 2, the gas inlet and gas outlet in the gas chamber are different, and the gas inlet and outlet can be easily controlled. Therefore, by passing the gas through the gas chamber, the adsorbent can easily and efficiently adsorb the target component.

[0101] (Item 3) According to the detection device described in Item 1 or 2, the first adsorbent has a honeycomb structure or a finned structure. The first adsorbent is configured to allow gas in the first gas chamber to pass through the honeycomb structure or the finned structure.

[0102] According to the detection device described in item 3, the target component in the gas is more easily adsorbed by the adsorbent. Therefore, the concentration of the target component in the gas chamber can be increased.

[0103] (Item 4) In the detection apparatus according to any one of items 1 to 3, the first stimulation section causes the first target component to detach from the first adsorbent by microwave heating or heater heating the first adsorbent.

[0104] According to the detection device described in item 4, the detachment and adsorption of the target component to the adsorbent can be easily controlled.

[0105] (Item 5) According to the detection device of Item 4, the first stimulation section heats the first adsorbent in such a way as to generate a temperature gradient in the first gas chamber.

[0106] According to the detection device described in item 5, convection is generated in the gas chamber, increasing the chance of gas flowing over the surface of the adsorbent, thus promoting the adsorption of the target component.

[0107] (Item 6) The detection device according to item 4 or 5 further comprises a cooler for cooling the first adsorbent heated by the first stimulation part.

[0108] According to the detection device described in item 6, the time required for the adsorbent to re-adsorb the target component can be shortened. Therefore, since the time required for one detection cycle can be shortened, the detection cycle can be accelerated.

[0109] (Item 7) The detection apparatus according to any one of items 1 to 6 further comprises: a light source for irradiating light onto the first adsorbent; and a detector for detecting the first target component adsorbed on the first adsorbent based on the emitted light from the first adsorbent.

[0110] According to the detection device described in item 7, even when a portion of the target component remains in the adsorbent, the concentration of that residual target component can be measured. Therefore, compared to measuring only the concentration of the target component in the gas, the concentration of the target component in the gas chamber can be determined more accurately.

[0111] (Item 8) The detection device according to any one of items 1 to 7, wherein the first gas chamber has an optical resonator structure.

[0112] According to the detection device described in item 8, the light absorption of the target component in the gas chamber can be amplified and detected. This improves the detection sensitivity of the target component.

[0113] (Item 9) The detection apparatus according to any one of items 1 to 8, wherein the first gas chamber has a separation section in front of the first gas chamber for removing specific components other than the first target component.

[0114] According to the detection device described in item 9, the target component can be accurately measured even when the gas in the gas pipeline contains substances that are not necessary for the target component to be measured or that would hinder it.

[0115] (Item 10) The detection apparatus according to any one of items 1 to 9 further comprises: a second gas chamber for introducing gas; and a second adsorbent disposed in the second gas chamber in such a way as to form a second unfilled space inside the second gas chamber, for adsorbing a second target component in the gas that is different from the first target component. The second unfilled space is a space not filled with the second adsorbent. The detection apparatus further comprises: a second stimulation unit that stimulates the second adsorbent to cause the second target component to detach into the second unfilled space; a second light source that irradiates light into the second unfilled space; and a second detector that detects the light emitted from the second gas chamber, wherein the measurement unit measures the second target component based on the output of the second detector.

[0116] The detection device described in item 10 is capable of simultaneously monitoring multiple target components in a gas pipeline.

[0117] (Item 11) Another embodiment involves a detection method comprising the following steps: introducing a gas containing a target component to be detected into a gas chamber, the gas chamber being filled with an adsorbent containing the target component in such a way that an unfilled space is formed inside. The unfilled space is the space where no adsorbent is filled. The detection method further comprises: applying a stimulus to the adsorbent to cause the target component to detach into the unfilled space; irradiating the unfilled space with light; detecting the light emitted from the gas chamber using a detector; and measuring the target component based on the output from the detector.

[0118] According to the detection method described in item 11, by placing the adsorbent in the gas chamber, the spatial volume between the target component detached from the adsorbent and the detection position can be minimized. This suppresses the dilution of the concentrated target component, thus enabling highly sensitive detection of the target component. Furthermore, since the transport path between the target component detached from the adsorbent and the detection position can be minimized, short-time detection of the target component is possible. As described above, a detection device capable of detecting a target component in a gas with short-time and high sensitivity can be provided.

[0119] The embodiments disclosed herein should be considered exemplary and not limiting in all respects. The scope of the invention is defined not by the foregoing description but by the claims, and is intended to include all modifications within the meaning and scope equivalent to the claims.

[0120] Explanation of reference numerals in the attached figures 1,1E,1F Gas chamber; 2,2E,2F,21,22 Adsorbent; 3,3E,3F Stimulation part; 4,4E,721,722 Light source; 5,5E,723,724 Detector; 8 Gas piping; 11,11F Inlet; 12,12F Outlet; 14,14F Housing; 15F Inner hole; 16F Space; 19,19F Unfilled space; 61,61E,61F,62,62E,62F Valve; 63,63E,64,64E Piping; 65F,66F Insulation material; 71,71F Cooler; 73 Separation part; 100 Detection device; 101,101A,101B,101C,101D,101E,101F Detection part; 102 Control device, 103 processor, 104 memory, 131, 131F, 132, 132F, 725, 726, 727, 728 optical windows, 141 inner wall.

Claims

1. A detection device comprising: The first gas chamber for gas introduction; and A first adsorbent is disposed in the first gas chamber in such a way that it forms a first unfilled space inside the first gas chamber, thereby adsorbing a first target component in the gas. The first unfilled space is the space that is not filled with the first adsorbent. The detection device also includes: Stimulation is applied to the first adsorbent to cause the first target component to detach into the first stimulation portion of the first unfilled space; A first light source that illuminates the first unfilled space; A first detector that detects the light emitted from the first air chamber; as well as A measurement unit that measures the first target component based on the output of the first detector.

2. The detection device according to claim 1, further comprising: an inlet opening and closing section for adjusting the introduction of the gas into the first gas chamber; and an outlet opening and closing section for adjusting the discharge of the gas from the first gas chamber.

3. The detection device according to claim 1, The first adsorbent has a honeycomb structure or a finned structure. The first adsorbent is configured to allow the gas in the first chamber to pass through the honeycomb structure or the fin structure.

4. The detection device according to claim 1, The first stimulation section causes the first target component to detach from the first adsorbent by microwave heating or heater heating the first adsorbent.

5. The detection device according to claim 4, The first stimulation section heats the first adsorbent in a manner that generates a temperature gradient in the first gas chamber.

6. The detection device according to claim 4, further comprising a cooler for cooling the first adsorbent heated by the first stimulation part.

7. The detection device according to claim 1, further comprising: A light source that irradiates the first adsorbent; and A detector that detects the first target component adsorbed on the first adsorbent based on emitted light from the first adsorbent.

8. The detection device according to claim 1, The first air chamber has an optical resonator structure.

9. The detection device according to claim 1, The first gas chamber has a separation section in front of it for removing specific components other than the first target component.

10. The detection device according to claim 1, further comprising: The second gas chamber for introducing the gas; and A second adsorbent is disposed in the second gas chamber in such a way that it forms a second unfilled space inside the second gas chamber, adsorbing a second target component in the gas that is different from the first target component. The second unfilled space is the space that is not filled with the second adsorbent. The detection device also includes: Stimulation is applied to the second adsorbent to cause the second target component to detach into the second unfilled space at the second stimulation portion; A second light source that illuminates the second unfilled space; and A second detector that detects the light emitted from the second air chamber. The measurement unit measures the second target component based on the output of the second detector.

11. A detection method comprising the following steps: A gas containing the target component to be detected is introduced into a gas chamber, which is filled with an adsorbent that adsorbs the target component in such a way that unfilled spaces are formed inside. The unfilled space is the space that is not filled with the adsorbent. The detection method also has the following features: The step of applying a stimulus to the adsorbent to cause the target component to detach into the unfilled space; The step of irradiating the unfilled space with light; The step of detecting light emitted from the gas chamber using a detector; and The step of measuring the target component based on the output from the detector.

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