Apparatus and method for simultaneous measurement of plasma degradation of organics

Abstract

The application belongs to the technical field of plasma degradation of organic matter, and is a device and method for synchronously measuring plasma degradation of organic matter, which comprises a plasma generation unit for forming low-temperature non-equilibrium plasma, an airflow regulation unit for regulating airflow, an infrared optical detection unit for constructing an infrared optical in-situ detection light path corresponding to a spatial position of a liquid reaction region, enabling infrared light of a specific wavelength to laterally pass through the liquid reaction region and collecting a transmitted light power signal in real time, and a data processing unit for receiving an electrical signal output by the infrared optical detection unit and performing signal processing, concentration calculation and result display. By structurally integrating the plasma treatment process and the optical detection process, the pollutant degradation and the concentration measurement are performed at the same spatial position and in the same time process, avoiding time lag and human error caused by traditional offline sampling, transfer and analysis, thereby improving the continuity and reliability of the measurement results.

Description

Technical Field

[0001] This application belongs to the field of plasma degradation of organic matter technology, specifically a device and method for synchronously measuring plasma degradation of organic matter. Background Technology

[0002] To address the problem of treating organic pollutants in water, researchers have proposed various physical, chemical, and biological treatment methods. Among them, plasma technology, due to its ability to generate a large number of highly reactive particles under normal temperature and pressure conditions, can efficiently destroy the molecular structure of organic pollutants and is considered a water treatment technology with broad application prospects. In particular, low-temperature plasma jets based on dielectric barrier discharge have advantages such as high energy utilization, mild reaction conditions, and wide applicability, and have attracted widespread attention in the field of organic pollutant degradation.

[0003] However, in existing research and applications of plasma degradation of organic pollutants in water, the evaluation of degradation effectiveness typically relies on offline sampling and analysis methods, such as ultraviolet-visible spectrophotometry, liquid chromatography, total organic carbon analysis, and chemical titration. These methods require multiple samplings and tests during the reaction process, which is not only cumbersome and time-consuming but also fails to reflect real-time changes in the degradation process. Furthermore, frequent sampling can disturb the reaction system, affecting the accuracy of the experimental results. Currently, there is a lack of a device capable of real-time, continuous monitoring of changes in the concentration of organic pollutants in water during plasma degradation, making it difficult to accurately characterize and evaluate the kinetics and treatment efficiency of the degradation process. Summary of the Invention

[0004] This application provides an apparatus and method for synchronously measuring the degradation of organic matter by plasma, which solves the problems of cumbersome detection process, insufficient real-time performance and large measurement error in the prior art.

[0005] The first aspect of this application provides an apparatus for simultaneously measuring plasma degradation of organic matter, comprising: A plasma generating unit includes a high-voltage electrode, a grounding electrode, and a dielectric tube disposed between the high-voltage electrode and the grounding electrode. The high-voltage electrode passes through the dielectric tube along its axial direction, and the grounding electrode is disposed on the outside of the dielectric tube. The airflow control unit includes a coaxially arranged air chamber, a first sleeve, and a second sleeve. The second sleeve and the first sleeve form a sleeve structure with an annular channel. The medium tube is disposed inside the first sleeve. The air chamber is used to introduce working gas and protective gas, and is connected to the annular channel and the inlet end of the first sleeve through the air outlet end. The outlet ends of the second sleeve and the first sleeve are provided with airflow outlet nozzles, and the outlet of the airflow outlet nozzles faces the liquid surface of the reaction vessel. An infrared optical detection unit is used to construct an infrared optical in-situ detection optical path corresponding to the spatial position of the liquid reaction area, so that infrared light of a specific wavelength passes laterally through the liquid reaction area and the transmitted light power signal is acquired in real time. The data processing unit is used to receive the electrical signal output by the infrared optical detection unit, and to perform signal processing, concentration calculation and result display.

[0006] Furthermore, a discharge gap is formed between the high-voltage electrode and the grounding electrode. The discharge gap is located within the annular channel between the first bushing and the second bushing, or between the outlet end of the first bushing and the outlet end of the second bushing.

[0007] Furthermore, the air inlet end of the air chamber is connected to a working gas inlet pipe and a protective gas inlet pipe, and a spiral flow stabilizer is provided in the air chamber so that the airflow entering from the working gas inlet pipe and the protective gas inlet pipe forms a rotating airflow after flowing through the spiral flow stabilizer, and then enters the annular channel through the air outlet end of the air chamber.

[0008] Furthermore, a flow equalization plate is provided between the air outlet end of the air chamber and the inlet end of the annular channel.

[0009] Furthermore, the gas flow outlet nozzle is a tapered nozzle, with the large-diameter end of the gas flow outlet nozzle connected to the outlet end of the second sleeve, and the small-diameter end of the gas flow outlet nozzle facing the center region of the liquid surface of the reaction vessel.

[0010] Furthermore, the infrared optical detection unit includes an infrared light source, an incident optical fiber, a receiving optical fiber, and a photoelectric detection device; the infrared light of a specific wavelength emitted by the infrared light source is introduced into one side of the reaction vessel through the incident optical fiber and passes laterally through the liquid reaction region along a predetermined optical axis; the transmitted light is collected by the receiving optical fiber disposed on the other side of the reaction vessel and transmitted to the photoelectric detection device.

[0011] Furthermore, the device also includes a dark box, in which the plasma generating unit, airflow control unit, infrared optical detection unit, and liquid reaction area are all disposed inside the dark box, forming a closed detection space.

[0012] A second aspect of this application provides a method for simultaneously measuring plasma degradation of organic matter, comprising: The working gas and the protective gas are introduced into the gas chamber through the gas inlet, and the airflow is stabilized and the flow field is reconstructed by the spiral flow stabilizer set inside the gas chamber, so that the gas forms a rotating airflow and is guided into the annular channel formed by the first sleeve and the second sleeve coaxially sleeved by the flow equalization plate. A high-frequency voltage is applied between the high-voltage electrode and the ground electrode, causing the gas between the high-voltage electrode and the ground electrode to ionize under the condition of dielectric barrier, forming a low-temperature non-equilibrium plasma. The plasma is then output axially through the gas flow outlet nozzle to the surface of the organic pollutant solution contained in the reaction vessel, forming a plasma action region near the liquid surface. At the same time, by controlling the flow rate and distribution of the gas flow, the liquid surface is kept in a low-disturbance state. While the plasma acts on the liquid surface, infrared light of a specific wavelength is introduced into one side of the reaction vessel through an incident optical fiber, so that the infrared light passes laterally along a predetermined optical axis through the solution area below the liquid surface in the reaction vessel, and is collected by a receiving optical fiber set on the other side of the reaction vessel and transmitted to a photoelectric detection device, which continuously collects the transmitted light power signal.

[0013] Furthermore, the transmitted light power signal collected by the photoelectric detection device is converted into a digital signal after signal amplification and filtering. The embedded processor calculates the concentration of the target organic pollutant in the solution area based on the transmitted light power signal and the pre-established quantitative calibration relationship between light attenuation and organic pollutant concentration.

[0014] Compared with the prior art, this application has at least the following beneficial effects: This application integrates the plasma processing process with the optical detection process, enabling pollutant degradation and concentration measurement to occur in the same spatial location and at the same time. This avoids the time lag and human error caused by traditional offline sampling, transfer, and analysis, thereby improving the continuity and reliability of the measurement results.

[0015] The discharge process of this application has a low temperature rise and high stability, thereby reducing the impact of liquid surface disturbance and bubble generation on optical measurements, and keeping the optical transmission path stable during the reaction process; the change in transmitted light intensity can continuously reflect the concentration change during the degradation process.

[0016] In this application, the reaction area formed by plasma action and the optical transmission path are located in the same liquid area. The transmitted light signal directly corresponds to the change in pollutant concentration during the reaction process. There is no need to sample or transfer the solution during the degradation process, thereby reducing the error introduced by operation and reducing the influence of external factors on the detection results. Attached Figure Description

[0017] Figure 1 This is a schematic diagram of a device for simultaneously measuring the degradation of organic matter by plasma, provided in an embodiment of this application. Figure 2 This is a schematic diagram of the integrated structure of the plasma generation unit and the airflow control unit provided in an embodiment of this application; Figure 3 A fitting curve of methylene blue provided in the embodiments of this application; Figure 4 The graph showing the relationship between the light power and degradation efficiency of methylene blue as a function of treatment time is provided in the embodiments of this application. In the diagram: 1. Metal perforated plate, 2. Pad block, 3. Photoelectric detection device, 4. Infrared light source, 5. Quartz optical fiber, 6. Light receiver, 7. Dark box, 8. Temperature controller, 9. Reaction vessel, 10. First sleeve, 11. Second sleeve, 12. Medium pipe, 13. Flow equalization plate, 14. Working gas inlet pipe, 15. High voltage electrode, 16. Protective gas inlet pipe, 17. Gas chamber, 18. Iron stand, 19. Spiral flow stabilizer, 20. Airflow outlet nozzle. Detailed Implementation

[0018] To make the objectives, technical solutions, and advantages of this application clearer, the following detailed description is provided in conjunction with embodiments. It should be understood that the specific embodiments described herein are merely illustrative and not intended to limit the scope of this application.

[0019] This application constructs an infrared optical in-situ detection optical path corresponding to the spatial location of the liquid reaction region, allowing infrared light of a specific wavelength to pass laterally through the liquid reaction region. The transmitted light power signal is then collected in real time by a photoelectric receiver located on the opposite side. The photoelectric receiver converts the optical signal into an electrical signal and transmits it to an embedded data processing and display unit for processing, thereby realizing real-time acquisition and concentration calculation of the transmitted light power signal. Based on this, a low-temperature plasma is generated near the gas-liquid interface through gas-liquid discharge, and the plasma continuously acts on the liquid reaction region. By controlling the airflow path and the discharge region, the liquid reaction region is kept in a low-disturbance state, thereby reducing liquid surface fluctuations and bubble generation, so as to achieve synchronous detection of changes in the concentration of organic pollutants in the reaction region.

[0020] See Figure 1 Combination Figure 2 As shown, a device for simultaneously measuring the degradation of organic matter by plasma includes: The plasma generating unit includes a high-voltage electrode 15, a ground electrode, and a dielectric tube 12 disposed between the high-voltage electrode 15 and the ground electrode. The high-voltage electrode 15 passes through the dielectric tube 12 along the axial direction of the dielectric tube 12, and the ground electrode is disposed on the outside of the dielectric tube 12. The airflow control unit includes a coaxially arranged air chamber 17, a first sleeve 10, and a second sleeve 11. The second sleeve 11 and the first sleeve 10 form a sleeve structure with an annular channel. The medium pipe 12 is disposed inside the first sleeve 10. The air chamber 17 is used to introduce working gas and protective gas, and is connected to the annular channel and the inlet end of the first sleeve 10 through the air outlet end. The outlet ends of the second sleeve 11 and the first sleeve 10 are provided with airflow outlet nozzles 20, and the outlet of the airflow outlet nozzles 20 faces the liquid surface of the reaction vessel 9. An infrared optical detection unit is used to construct an infrared optical in-situ detection optical path corresponding to the spatial position of the liquid reaction area, so that infrared light of a specific wavelength passes laterally through the liquid reaction area and the transmitted light power signal is acquired in real time. The data processing unit is used to receive the electrical signal output by the infrared optical detection unit, and to perform signal processing, concentration calculation and result display.

[0021] In one embodiment, the plasma generating unit is disposed above the reaction vessel 9, arranged vertically. The plasma generating unit mainly consists of a high-voltage electrode 15, a dielectric tube 12, a grounding electrode (not marked in the figure), and a high-frequency power supply (not shown in the figure). The high-voltage electrode 15 passes through the interior of the dielectric tube 12 along its axial direction. The grounding electrode is disposed on the outside of the dielectric tube 12. A dielectric barrier layer is formed between the high-voltage electrode 15 and the grounding electrode through the wall of the dielectric tube 12. A discharge gap is formed between the lower end of the dielectric tube 12 and the lower end of the high-voltage electrode 15. The upper end of the high-voltage electrode 15 is connected to one output terminal of the high-frequency power supply via a wire, and the grounding electrode is connected to the other output terminal of the high-frequency power supply via a wire and grounded.

[0022] The high-voltage electrode 15 is made of a conductive metal material. Preferably, the high-voltage electrode 15 is a copper rod or a brass rod, the surface of which is polished to reduce surface roughness, thereby avoiding local electric field concentration caused by surface tip effect. The cross-sectional shape of the copper rod can be circular, square or other regular geometric shape, preferably circular, so as to obtain uniform concentric arrangement within the dielectric tube 12.

[0023] The diameter of the high-voltage electrode 15 is determined based on the discharge power and the inner diameter of the dielectric tube 12. Preferably, the diameter of the high-voltage electrode 15 is 1mm to 6mm. The length of the high-voltage electrode 15 is greater than the length of the dielectric tube 12, so that the upper end of the high-voltage electrode 15 extends beyond the upper port of the dielectric tube 12 to facilitate connection of wires; the lower end of the high-voltage electrode 15 is located inside the dielectric tube 12 near the lower port, or extends a certain distance beyond the lower port of the dielectric tube 12. Preferably, the lower end of the high-voltage electrode 15 is located inside the dielectric tube 12, and the distance between it and the lower port of the dielectric tube 12 is 0.5mm to 5mm, which corresponds to the width of the discharge gap.

[0024] The dielectric tube 12 is an axially extending cylindrical tubular structure with an inner diameter larger than the outer diameter of the high-voltage electrode 15. This allows the high-voltage electrode 15 to pass through the dielectric tube 12, forming an annular channel between the outer wall of the high-voltage electrode 15 and the inner wall of the dielectric tube 12. The dielectric tube 12 is made of an insulating material with high dielectric strength, good withstand voltage, and a stable dielectric constant. Preferably, the dielectric tube 12 is made of quartz or alumina ceramic. Other dielectric materials can also be used, such as borosilicate glass, polytetrafluoroethylene, or polyimide, but quartz and ceramic are the most preferred options.

[0025] The grounding electrode is disposed on the outside of the first sleeve 10. Preferably, the grounding electrode is an annular electrode, sleeved on the outer wall of the first sleeve 10 and tightly fitted to the outer wall of the first sleeve 10. The inner diameter of the annular electrode matches the outer diameter of the first sleeve 10, and is fixed to the outer wall of the first sleeve 10 by interference fit or adhesive bonding. The axial width of the annular electrode is 2mm to 10mm, and its axial position corresponds to the height range of the lower end of the high-voltage electrode 15, so as to ensure that the discharge gap is located between the lower end of the high-voltage electrode 15 and the annular electrode.

[0026] Alternatively, the grounding electrode can be a mesh electrode or a spiral coil electrode, wrapped or covered around the outer wall of the first sleeve 10. Mesh electrodes or spiral coil electrodes help increase the contact area between the electrode and the outer wall of the dielectric tube 12, improving the uniformity of the electric field distribution.

[0027] The grounding electrode is made of a conductive metal material, preferably copper strip, copper foil, or stainless steel strip. The grounding electrode is connected to the grounding terminal of the high-frequency power supply via a wire and is reliably grounded.

[0028] In a preferred embodiment of this application, the dielectric tube 12 is disposed inside the first sleeve 10, and the first sleeve 10 is disposed inside the second sleeve 11, forming a three-layer coaxial sleeve structure. Specifically, from the inside to the outside along the radial direction, the structure consists of: a high-voltage electrode 15, a dielectric tube 12, an annular space between the first sleeve 10 and the dielectric tube 12 (serving as an inner airflow channel), the first sleeve 10, and an annular channel between the second sleeve 11 and the first sleeve 10 (serving as an outer annular air curtain channel).

[0029] A first annular airflow channel is formed between the outer wall of the dielectric tube 12 and the inner wall of the first sleeve 10. This channel is used to circulate the working gas, allowing the working gas to fully contact the plasma within the discharge region. A second annular airflow channel is formed between the outer wall of the first sleeve 10 and the inner wall of the second sleeve 11. This channel is used to circulate the protective gas, thereby forming an annular gas curtain to envelop the working gas.

[0030] The upper end of the medium tube 12 is positioned and installed with the upper end of the first sleeve 10 via a fixing component (not shown in the figure). Preferably, the fixing component has a mounting hole that matches the outer diameter of the medium tube 12. The medium tube 12 passes through the mounting hole, and the upper end of the medium tube 12 is flush with or slightly protruding from the upper surface of the fixing component, and is sealed and fixed with silicone. The upper end of the first sleeve 10 is also positioned and installed via a fixing component, so that the medium tube 12, the first sleeve 10, and the second sleeve 11 are coaxial.

[0031] The working principle of the plasma generation unit is as follows: Under the influence of the high-frequency, high-voltage electrical signal applied by the high-frequency power supply, a strong electric field is formed between the high-voltage electrode 15 and the grounding electrode. Since the wall of the dielectric tube 12 acts as a barrier dielectric layer between the high-voltage electrode 15 and the grounding electrode, the gas within the discharge gap ionizes under the strong electric field, forming electron avalanches and streamers. When the electron avalanches reach the dielectric surface, charge accumulates on the surface, forming a built-in electric field opposite to the direction of the applied electric field. This reduces the local electric field strength, thereby inhibiting the further development of electron avalanches and causing the discharge process to self-extinguish. With the periodic changes of the applied electric field, the above process repeats at an extremely high frequency, manifested as the rapid generation and extinguishing of numerous micro-discharge channels within the discharge gap.

[0032] Because the duration of each micro-discharge channel is extremely short (typically on the order of nanoseconds to microseconds), and the discharge energy is dispersed among a large number of micro-discharge channels, the overall discharge process does not form a continuous high-current arc. The gas temperature rise in the discharge region is effectively controlled (typically below 50°C), thus stabilizing the discharge process in a non-equilibrium low-temperature plasma state. Simultaneously, during the discharge process, gas molecules are excited and ionized by high-energy electron collisions, generating a large number of active substances, including high-energy electrons, ions, free radicals, and excited-state molecules. These active substances, carried by the airflow, move axially and are output through the airflow outlet nozzle 20, acting on the solution surface to degrade organic pollutants.

[0033] In this embodiment, the airflow control unit is used to continuously provide a stable airflow to the discharge region and to perform multi-level control over the flow state, distribution pattern, and outlet jet characteristics of the airflow. The airflow control unit mainly consists of an air chamber 17, a first sleeve 10, a second sleeve 11, a spiral flow stabilizer 19, a flow equalization plate 13, and an airflow outlet nozzle 20. The air chamber 17 is located upstream of the first sleeve 10 and the second sleeve 11. The first sleeve 10 and the second sleeve 11 are coaxially sleeved, with the second sleeve 11 sleeved outside the first sleeve 10. An annular channel is formed between the first sleeve 10 and the second sleeve 11, which serves as an annular air curtain channel. The airflow outlet nozzle 20 is located at the outlet end of the first sleeve 10 and the second sleeve 11, with the outlet of the airflow outlet nozzle 20 facing the liquid surface of the solution inside the reaction vessel 9.

[0034] The dielectric tube 12 is disposed inside the first sleeve 10 and is coaxially arranged with the first sleeve 10. A high-voltage electrode 15 is disposed inside the dielectric tube 12, and a discharge gap is formed between the high-voltage electrode 15 and the grounding electrode disposed outside the second sleeve 11. The outlet end of the gas chamber 17 is connected to the internal channel of the first sleeve 10 (i.e., the annular space between the dielectric tube 12 and the first sleeve 10) and the annular channel between the first sleeve 10 and the second sleeve 11, so that the working gas flows through the discharge area inside the first sleeve 10, and the protective gas forms an annular gas curtain through the annular channel.

[0035] The air chamber 17 is located at the upstream end of the airflow control unit, that is, above the first sleeve 10 and the second sleeve 11. The air chamber 17 is a hollow shell structure, and a mixing chamber is formed inside it. Preferably, the air chamber 17 is a cylindrical structure with a circular cross-section of its inner cavity, and the central axis of the air chamber 17 coincides with the central axis of the first sleeve 10 and the second sleeve 11.

[0036] At least two air inlets are provided on the side wall of the gas chamber 17, namely a working gas inlet pipe 14 and a protective gas inlet pipe 16. The working gas inlet pipe 14 is used to introduce the working gas, which is a gas that participates in the discharge ionization process and provides plasma active material. Preferably, the working gas is one or a mixture of argon, helium, and nitrogen. The protective gas inlet pipe 16 is used to introduce the protective gas, which is a gas that does not participate in or participates less in the discharge reaction, and is used to form a gas curtain protective layer around the discharge area. Preferably, the protective gas is argon or helium.

[0037] Preferably, the working gas inlet pipe 14 and the protective gas inlet pipe 16 are tangentially disposed on the side wall of the gas chamber 17, so that the gas entering the gas chamber 17 has an initial tangential velocity component, thereby forming a rotating airflow within the gas chamber 17. Alternatively, the working gas inlet pipe 14 and the protective gas inlet pipe 16 can be radially disposed on the side wall of the gas chamber 17, in which case the internally disposed spiral flow stabilizer 19 is needed to guide the airflow rotation.

[0038] The working gas inlet pipe 14 is connected to the working gas source via a pipeline, and a first gas flow meter (not shown in the figure) is installed on the pipeline for independent adjustment and control of the working gas flow rate. The protective gas inlet pipe 16 is connected to the protective gas source via a pipeline, and a second gas flow meter (not shown in the figure) is installed on the pipeline for independent adjustment and control of the protective gas flow rate. By controlling the flow rates of the working gas and the protective gas separately, the coating thickness of the annular gas curtain on the central airflow and the flow rate ratio between the two can be adjusted to adapt to different discharge conditions and solution properties.

[0039] The lower end of the gas chamber 17 is provided with a gas outlet, which is connected to the internal channel of the first sleeve 10 and the annular channel between the first sleeve 10 and the second sleeve 11. Preferably, the end face of the gas outlet of the gas chamber 17 is sealed to the upper end face of the first sleeve 10 and the second sleeve 11 by a sealing element (such as an O-ring or silicone sealant) to prevent gas leakage.

[0040] In one embodiment, the air inlet end of the air chamber 17 is connected to a working gas inlet pipe 14 and a protective gas inlet pipe 16, and a spiral flow stabilizer 19 is provided in the air chamber 17 so that the airflow entering from the working gas inlet pipe 14 and the protective gas inlet pipe 16 forms a rotating airflow after flowing through the spiral flow stabilizer 19, and then enters the annular channel through the air outlet end of the air chamber 17.

[0041] A spiral flow stabilizer 19 is disposed inside the gas chamber 17, downstream of the working gas inlet pipe 14 and the protective gas inlet pipe 16, and upstream of the gas outlet of the gas chamber 17. That is, the gas entering from the working gas inlet pipe 14 and the protective gas inlet pipe 16 must first flow through the spiral flow stabilizer 19 before exiting the gas chamber 17. This positioning ensures that the gas undergoes flow stabilization and flow field reconstruction processing by the spiral flow stabilizer 19 before entering the first sleeve 10 and the second sleeve 11. The spiral flow stabilizer 19 is a spiral guide vane or spiral blade structure. The spiral axis of the spiral flow stabilizer 19 coincides with the central axis of the gas chamber 17.

[0042] The working principle of the spiral flow stabilizer 19 is as follows: When the working gas and the protective gas enter the gas chamber 17 through the working gas inlet pipe 14 and the protective gas inlet pipe 16 respectively, the gas first enters the spiral channel of the spiral flow stabilizer 19. Under the guidance of the spiral channel, the flow direction of the gas changes from axial flow to rotational flow along the spiral path. During this process, the turbulent vortices and velocity pulsations in the gas are suppressed by the wall of the spiral channel. At the same time, the gas undergoes multiple mixing and redistribution during rotation, making the velocity distribution of the airflow tend to be uniform. After being processed by the spiral flow stabilizer 19, the gas enters the first sleeve 10 and the annular channel in a stable rotational flow state, thereby providing an initial flow field with good flow uniformity and stability for the subsequent discharge process.

[0043] Both the first sleeve 10 and the second sleeve 11 are axially extending cylindrical tubular structures, and they are coaxially fitted together. The first sleeve 10 is disposed inside the second sleeve 11, that is, the second sleeve 11 is fitted onto the outside of the first sleeve 10. An annular channel is formed between the outer wall of the first sleeve 10 and the inner wall of the second sleeve 11, and this annular channel extends axially to form an annular air curtain channel.

[0044] The axial length of the first sleeve 10 is less than the axial length of the second sleeve 11, meaning that the lower end (outlet end) of the first sleeve 10 is located inside the lower end (outlet end) of the second sleeve 11, forming a length difference along the axial direction between them. This length difference forms an axially extended region between the outlet ends of the first sleeve 10 and the second sleeve 11. This region serves as an airflow development section, allowing the airflow to undergo sufficient flow field development before exiting through the airflow outlet nozzle 20, thereby further optimizing the airflow velocity distribution and turbulence characteristics.

[0045] Both the first sleeve 10 and the second sleeve 11 are made of insulating and high-voltage resistant materials. Preferably, both the first sleeve 10 and the second sleeve 11 are quartz tubes. Quartz material has the advantages of stable dielectric constant (relative dielectric constant of approximately 3.75), low dielectric loss, high temperature resistance (softening point above approximately 1600℃), good light transmittance, and strong resistance to chemical corrosion. Alternatively, the first sleeve 10 and the second sleeve 11 can be made of borosilicate glass or alumina ceramic material.

[0046] In one embodiment, a flow equalization plate 13 is disposed between the outlet end of the air chamber 17 and the inlet end of the annular channel. The flow equalization plate 13 is located at the inlet end of the annular channel between the first sleeve 10 and the second sleeve 11. The flow equalization plate 13 is an annular plate structure, with its outer diameter matching the inner diameter of the second sleeve 11 and its inner diameter matching the outer diameter of the first sleeve 10. The flow equalization plate 13 is disposed within the radial space between the first sleeve 10 and the second sleeve 11. Multiple vent holes are formed on the flow equalization plate 13, and the vent holes are evenly distributed circumferentially. The opening direction of the vent holes is parallel to the axial direction of the first sleeve 10 and the second sleeve 11, that is, the vent holes penetrate the flow equalization plate 13 axially.

[0047] In one embodiment, the airflow outlet nozzle 20 is a tapered nozzle. The large-diameter end of the airflow outlet nozzle 20 is connected to the outlet end of the second sleeve 11, and the small-diameter end of the airflow outlet nozzle 20 faces the center region of the liquid surface in the reaction vessel 9. That is, it is located at the downstream end of the airflow control unit, at the lower outlet of the second sleeve 11. The airflow outlet nozzle 20 is arranged vertically along the axial direction, and its central axis coincides with the central axis of the first sleeve 10 and the second sleeve 11 to ensure the axisymmetric flow characteristics of the airflow.

[0048] The airflow outlet nozzle 20 is a tapered nozzle, meaning its internal cross-sectional area gradually decreases along the airflow direction (i.e., from top to bottom). The large-diameter end (i.e., the inlet end) of the airflow outlet nozzle 20 is connected to the outlet end of the second sleeve 11, and the small-diameter end (i.e., the outlet end) of the airflow outlet nozzle 20 faces the liquid surface of the reaction vessel 9, with the outlet of the small-diameter end directly facing the center region of the organic pollutant solution surface within the reaction vessel 9. The airflow outlet nozzle 20 is fixed to the outlet end of the second sleeve 11 by threaded connection, flange connection, or adhesive bonding. In a preferred embodiment of this application, the large-diameter end of the airflow outlet nozzle 20 is sleeved outside the outlet end of the second sleeve 11, and the two are fixed together by interference fit or silicone adhesive bonding, with the connection sealed to prevent gas leakage.

[0049] The enveloping airflow, after fully developing through the annular air curtain channel between the first sleeve 10 and the second sleeve 11, and the central airflow carrying plasma-active material, after passing through the annular channel between the medium pipe 12 and the first sleeve 10, converge at the outlet end of the first sleeve 10 to form a composite jet with the central airflow as the core and the annular air curtain as the enveloping layer. This composite jet then enters the large-diameter end of the airflow outlet nozzle 20.

[0050] Within the contraction channel of the tapered nozzle, as the flow cross-sectional area gradually decreases along the flow direction, according to the continuity equation, the average axial velocity of the airflow gradually increases along the flow direction, provided that the change in airflow density is negligible. Simultaneously, according to Bernoulli's equation, neglecting the height difference, the static pressure of the airflow decreases with increasing velocity; that is, the dynamic pressure of the airflow increases while the static pressure decreases, and some pressure energy is converted into kinetic energy.

[0051] During the acceleration process described above, because the airflow outlet nozzle 20 has an axisymmetric contraction structure, the streamlines of the airflow gradually converge towards the center within the contraction section. The annular air curtain applies continuous centripetal pressure to the central airflow within the contraction section, suppressing the radial diffusion tendency of the central airflow and keeping its streamlines straight and parallel. After the acceleration and convergence of the entire contraction section, the airflow reaches its maximum velocity at the small-diameter end (i.e., the outlet end) of the airflow outlet nozzle 20, while the diameter of the jet cross-section shrinks to match the outlet orifice diameter.

[0052] The jet ejected from the outlet of the airflow exit nozzle 20 exhibits an axisymmetric velocity distribution with a high center and low edges, clear jet boundaries, and low turbulence. The jet contains high-energy electrons, ions, free radicals, and excited-state molecules carried by the discharge region, thus constituting a plasma jet.

[0053] In one embodiment, the infrared optical detection unit mainly consists of an infrared light source 4, an incident optical fiber, a receiving optical fiber (not marked in the figure), an optical fiber collimator (optional), a photoelectric detection device 3, and a corresponding optical fixing bracket. The infrared light source 4 is disposed outside the reaction vessel 9. One end of the incident optical fiber is connected to the light output end of the infrared light source 4, and the other end (i.e., the exit end) of the incident optical fiber is disposed on one side of the reaction vessel 9, facing the interior of the reaction vessel 9. One end (i.e., the incident end) of the receiving optical fiber is disposed on the other side of the reaction vessel 9, opposite to the exit end of the incident optical fiber, and the other end of the receiving optical fiber is connected to the light signal input end of the photoelectric detection device 3. The space between the exit end of the incident optical fiber and the incident end of the receiving optical fiber constitutes the infrared light transmission path, which laterally passes through the solution region below the liquid surface inside the reaction vessel 9. The reaction vessel 9 is made of quartz material that is resistant to high temperatures and corrosion and has high transmittance to infrared light.

[0054] The optical axis of the infrared optical detection unit (i.e., the line connecting the exit end of the incident optical fiber and the incident end of the receiving optical fiber) corresponds precisely in space to the plasma interaction region. Specifically, the optical axis passes through the solution region below the liquid surface within the reaction vessel 9 in the horizontal direction, and its vertical height corresponds to the solution region directly below the outlet of the gas flow outlet nozzle 20.

[0055] More specifically, the outlet of the gas flow outlet nozzle 20 is directly opposite the central region of the solution surface within the reaction vessel 9. After the plasma jet is ejected from the gas flow outlet nozzle 20, it acts axially downwards at the center of the liquid surface, forming a liquid reaction region below the liquid surface corresponding to the plasma action position. The liquid reaction region extends vertically downwards from the liquid surface to a certain depth, and horizontally is distributed with the center of the liquid surface as the center and a certain radius.

[0056] The plasma is output through the gas flow outlet nozzle 20, which is used to confine, guide, and shape the gas flow, ensuring good concentration and stability of the plasma in the axial direction. This creates a stable and low-disturbance plasma interaction region at the liquid surface of the reaction vessel 9. By controlling the gas flow distribution and jet structure, liquid surface fluctuations and bubble generation can be effectively suppressed, maintaining a relatively stable liquid state within this region, thus forming a repeatable liquid reaction zone.

[0057] While a stable liquid reaction zone is formed, infrared light of a specific wavelength emitted by infrared light source 4 is introduced into one side of reaction vessel 9 via quartz optical fiber 5 and passes laterally through the liquid reaction zone affected by plasma along a predetermined optical axis. The transmitted light is collected by quartz optical fiber 5 on the other side of reaction vessel 9 and transmitted to photodetector 6. The photoelectric detection device 3 continuously detects the transmitted light signal, obtains the dynamic signal of the transmitted light power changing with time, and outputs the signal to the embedded data processing unit. The data processing unit performs real-time calculation and processing on the acquired signal and automatically calculates the concentration of the target organic pollutant based on the pre-established concentration calibration relationship, realizing continuous monitoring and real-time output of pollutant concentration during the degradation process. Resistance heating is installed inside reaction vessel 9, and the temperature is controlled by temperature controller 8.

[0058] Because the optical transmission path directly passes through the reaction region formed by plasma, during the continuous action of the plasma, organic pollutant molecules in the solution undergo gradual oxidative degradation under the influence of active particles. Their molecular structure and concentration continuously change, altering their absorption capacity for specific wavelengths of infrared light. This allows the transmitted light power signal to reflect the dynamic changes in pollutant concentration within the region in real time. As the degradation reaction continues, the pollutant concentration gradually decreases, the absorption of incident light by the solution weakens, and the transmitted light intensity exhibits a regular increasing trend over time. By continuously acquiring the optical power signal and based on the quantitative relationship between light attenuation and concentration, dynamic calculation and real-time characterization of pollutant concentration changes can be achieved.

[0059] The optical detection path is designed to match the spatial arrangement of the plasma interaction region. The optical axis passes through the plasma-affected solution reaction region, forming a stable optical transmission path within the reaction region. This ensures that the optical detection path always covers the liquid area where the plasma effect is most significant, thereby guaranteeing that the acquired transmitted light signal directly corresponds to the reaction state within the plasma interaction region. Through coordinated design of airflow distribution, flow field state, and optical path position, the plasma interaction region remains relatively stable in space, while ensuring the fixity and repeatability of the optical transmission path. This avoids optical signal fluctuations caused by liquid surface disturbance, bubble generation, or flow field instability.

[0060] To further improve detection accuracy, the entire synchronous measurement system is housed within a dark box 7, forming a closed detection space. The dark box 7 is preferably made of a material with high structural strength and excellent light-shielding performance. Its inner walls undergo a matte blackening treatment or are covered with a high-absorption matte layer to significantly reduce internal reflectivity. This matte treatment of the inner walls effectively absorbs stray light and multiple reflections entering the box, preventing secondary reflection interference within the closed space and ensuring unidirectional propagation of the detection beam along a predetermined optical axis. Compared to an open optical path structure, this closed dark box 7 structurally blocks the intrusion of ambient light, preventing fluctuations in transmitted light intensity measurement results caused by fluorescent lamps, display screen light sources, and changes in natural light, ensuring that optical detection is always performed under stable and controllable background conditions. Simultaneously, the structure of the dark box 7 provides a relatively constant internal spatial environment for the detection system. Since the detection process involves precise measurements of minute light intensity changes, external light flicker, power fluctuations, and electromagnetic environment changes can all introduce background noise. The dark box 7, through physical shielding, weakens the impact of external light radiation and electromagnetic interference on the photoelectric receiver to a certain extent, thereby improving the stability of signal acquisition. Furthermore, the enclosed space reduces optical path disturbance caused by airflow, avoiding beam shift or spot drift caused by changes in airflow refractive index, further ensuring the repeatability and consistency of measurement results. In terms of structural design, the dark box 7 is equipped with supporting components and limiting structures for fixing various optical elements, including a metal perforated plate 1 as the base plate, used to fix the infrared light source 4, photoelectric detection device 3, temperature controller 8, and pad 2. The reaction container 9 is installed via the pad 2. The infrared light source 4 is located on one side of the reaction container 9, and the photoelectric detection device 3 is located on the other side, transmitting light signals through quartz optical fibers 5. The output end of the infrared light source 4, the incident fiber interface, the gas path connection port, the line connection port, the position of the reaction container 9, and the output fiber interface are all positioned and installed using rigid brackets. The components are precisely fitted together using positioning holes on the metal perforated plate 1 and pad 2, forming a stable coaxial optical axis arrangement structure. The plasma generation unit is fixed above the gas chamber 17 via an iron frame 18. This rigid connection method effectively reduces optical axis misalignment caused by experimental operations, table vibrations, or minor collisions, preventing light deviation during detection and ensuring optical path stability from a structural perspective. By precisely limiting the distance between the optical windows on both sides of the reaction vessel 9, the effective optical path length of light in the solution remains constant.

[0061] Specifically, this device uses a gas-liquid discharge method to generate low-temperature non-equilibrium plasma. A confined discharge gap is formed between the built-in high-voltage electrode 15 and the dielectric structure. Under the constraint of the second sleeve 11, an axisymmetric electric field distribution is formed, which stabilizes the discharge process and forms low-temperature non-equilibrium plasma. On this basis, the plasma acts on the solution surface and forms a corresponding reaction region inside the solution, so that organic pollutants continuously undergo degradation reactions in this region. At the same time, the optical transmission path passes through the reaction region inside the solution, so that the transmitted light signal changes with the pollutant concentration, and the pollutant concentration can be calculated in real time.

[0062] Due to the regulating effect of the dielectric layer on charge accumulation and discharge process, the discharge is periodically generated and extinguished in the form of micro-discharge, thereby suppressing current surges and avoiding arc discharge. This results in a lower temperature rise and higher stability during the discharge process, which in turn reduces the impact of liquid surface disturbance and bubble formation on optical measurements, keeping the optical transmission path stable during the reaction. Under these conditions, changes in transmitted light intensity can continuously reflect concentration changes during the degradation process.

[0063] With the above structural setup, the reaction area formed by plasma action and the optical transmission path are located in the same liquid area. The transmitted light signal directly corresponds to the change in pollutant concentration during the reaction process. There is no need to sample or transfer the solution during the degradation process, thereby reducing the error introduced by operation and reducing the influence of external factors on the detection results.

[0064] In this embodiment, the device introduces an optical detection method using fiber optic transmission during the plasma degradation process. This enables the detection optical path to operate stably in a high-voltage discharge environment and improves the stability of the measurement process by utilizing the insensitivity of optical signals to electromagnetic interference. At the same time, optical detection has a high response capability to concentration changes, enabling continuous measurement of pollutant concentration changes.

[0065] In one embodiment, the data processing unit includes a signal acquisition module, an analog-to-digital conversion module, a data processing module, and a display module; wherein, the signal acquisition module is used to receive analog electrical signals, the analog-to-digital conversion module is used to convert analog electrical signals into digital signals, the data processing module performs concentration calculation on the digital signals based on a preset calibration relationship, and the display module is used to display the calculated target pollutant concentration in real time.

[0066] The data processing module is composed of a microcontroller, microprocessor or embedded control chip, used to process digital signals and output the target pollutant concentration result according to the preset calibration relationship.

[0067] The optical transmission path constructs a non-contact detection structure through optical fiber, enabling real-time transmission of transmitted light signals during the reaction process. This reduces the impact of high-frequency discharge environment and electromagnetic interference on the detection process and improves the stability of the measurement process. At the same time, concentration measurement can be completed directly in the reaction liquid, avoiding errors caused by liquid sampling, transfer and offline analysis in traditional detection processes, and reducing detection steps and improving measurement efficiency.

[0068] The working principle of the device for synchronously measuring the degradation of organic matter by plasma provided in this embodiment is mainly based on the degradation of organic pollutants by low-temperature plasma generated by gas-liquid discharge, combined with optical transmission detection method to achieve real-time synchronous measurement of solution concentration. First, under the action of an external high-frequency power supply, a strong electric field is formed between the high-voltage electrode 15 and the ground electrode in the plasma generating unit, and the discharge process is restricted by the dielectric tube 12, causing the gas to ionize and generate stable low-temperature plasma. During the discharge process, gas molecules are excited and ionized, generating a large number of active substances with strong oxidizing capabilities. These active substances are transported to the surface of the organic pollutant solution under the action of gas flow, forming a corresponding plasma interaction region near the liquid surface. This region of liquid is continuously subjected to plasma action, forming a reaction zone, thereby triggering a series of redox reactions, causing the organic pollutant molecular structure to gradually break down and degrade.

[0069] During plasma interaction, the liquid surface is kept in a low-disturbance state by controlling the airflow path and distribution, thereby suppressing surface fluctuations and bubble generation to maintain the stability of the liquid state within the reaction region. Based on this stable reaction region, an optical transmission detection path is constructed at its corresponding position, allowing detection light of a specific wavelength to pass laterally through the plasma-treated liquid reaction region. The transmitted light power signal is collected in real time by a photoelectric receiver on the opposite side, and the optical signal is converted into an electrical signal and transmitted to an embedded data processing and display unit for real-time calculation and processing, realizing the automated calculation and output of pollutant concentration. Since organic pollutant molecules in the solution absorb light of a specific wavelength, the intensity of the transmitted light changes with the pollutant concentration, thereby achieving real-time characterization of pollutant concentration changes within the reaction region.

[0070] Meanwhile, the stable transmission of the optical detection path depends on the stable gas-liquid interface formed during the plasma interaction. By regulating the airflow path and airflow state, liquid surface fluctuations and bubble generation are effectively suppressed, thereby ensuring that the detection light has a stable transmission path in the reaction area. Under these conditions, the plasma degradation process and the optical measurement process are carried out synchronously in the same liquid reaction area, so that the transmitted light power signal can reflect the changes in the concentration of organic pollutants in the area in real time, thus forming an integrated system in which degradation and measurement are carried out in tandem.

[0071] In another embodiment, this application provides a method for simultaneously measuring plasma degradation of organic matter, comprising: The working gas and protective gas are introduced into the gas chamber 17 through gas inlets, respectively. A spiral flow stabilizer 19, located inside the gas chamber 17, stabilizes the airflow and reconstructs the flow field, causing the gas to form a rotating airflow. This airflow is then guided by the flow equalization plate 13 into an annular channel formed by the coaxially fitted first sleeve 10 and second sleeve 11. In the plasma degradation of organic pollutants, air is used as the working gas, and argon as the protective gas. Air provides reactive oxygen species, and the highly reactive particles generated during discharge can effectively attack and decompose organic pollutant molecules. Simultaneously, argon, as an inert protective gas, not only helps maintain the stability of the discharge region and suppress unnecessary side reactions, but also optimizes discharge conditions through its high ionization efficiency, thereby synergistically improving the efficiency and stability of the entire degradation process.

[0072] A high-frequency voltage is applied between the high-voltage electrode 15 and the ground electrode, causing the gas between the high-voltage electrode 15 and the ground electrode to ionize under the condition of dielectric barrier, forming a low-temperature non-equilibrium plasma. The plasma is then output axially through the gas flow outlet nozzle 20 to the surface of the organic pollutant solution contained in the reaction vessel 9, forming a plasma action area near the liquid surface. At the same time, by controlling the flow rate and distribution of the gas flow, the liquid surface is kept in a low-disturbance state. While the plasma acts on the liquid surface, infrared light of a specific wavelength is introduced into one side of the reaction vessel 9 through the incident optical fiber, so that the infrared light passes laterally along a predetermined optical axis through the solution area below the liquid surface in the reaction vessel 9, and is collected by the receiving optical fiber set on the other side of the reaction vessel 9 and transmitted to the photoelectric detection device 3, which continuously collects the transmitted light power signal.

[0073] The transmitted light power signal collected by the photoelectric detection device 3 is converted into a digital signal after signal amplification and filtering. The embedded processor calculates the concentration of the target organic pollutant in the solution area based on the transmitted light power signal and the pre-established quantitative calibration relationship between light attenuation and organic pollutant concentration.

[0074] The apparatus and method for synchronously measuring the degradation of organic matter by plasma, as provided in the embodiments of this application, simultaneously measure the concentration of methylene blue solution during plasma treatment. First, a series of methylene blue standard solutions of known concentrations are prepared and added to reaction vessel 9 to ensure the concentration gradient covers the required experimental range. Under constant infrared light source power and fixed optical path conditions, incident light is coupled to the solution system via optical fiber, allowing the beam to pass through the liquid medium along a preset optical path and be received by photoelectric detection device 3. Photoelectric detection device 3 records the transmitted light intensity and converts it into a corresponding optical power signal. To eliminate the influence of the solvent itself and system background signals, deionized water is used as a reference sample, and its transmitted light intensity or light attenuation value is measured as a benchmark. The light attenuation value of the methylene blue solution to be tested is compared with the light attenuation value of the reference water sample to obtain the effective light attenuation caused by solute absorption, thereby improving the accuracy and comparability of the measurement results. In the data processing stage, a concentration-optical response scatter plot is constructed with solution concentration as the abscissa and the light attenuation value after difference correction as the ordinate. Linear regression analysis of the experimental data was performed using the least squares method to obtain the fitted line and its functional expression, and the correlation coefficient was calculated to evaluate the goodness of fit. The results showed that within the set concentration range, there was a significant linear relationship between the light attenuation of the methylene blue solution and its concentration. Figure 3 As shown.

[0075] In terms of experimental conditions, the working voltage was controlled at approximately 6 kV; air was used as the working gas for discharge, with a flow rate of 1 L / min; argon was used as the protective gas, also with a flow rate of 1 L / min. A 2 mg / L methylene blue solution was used as a simulated organic wastewater system for plasma jet degradation and simultaneous optical detection experiments. Under fixed optical path length and a stable infrared light source with a power of 4, deionized water was used as a reference sample, and the infrared light transmission power was measured to be -39.2 dBm, which served as the system background reference value. In the untreated state, the transmitted light power of the 2 mg / L methylene blue solution was -45.5 dBm. After 10 min of plasma jet treatment, the transmitted light power increased to -43.0 dBm, indicating a decrease in the absorption of incident light by the solution. The light attenuation ratio was calculated based on the difference in light power and corrected using the reference sample signal, showing that the absorbance of the solution decreased from the initial 0.065 to 0.040. The decrease in absorbance reflects a significant decrease in the concentration of chromophores in the solution with treatment time. Based on this, the degradation efficiency was further calculated to be approximately 37%. This result indicates that, under the set discharge parameters and gas conditions, the in-situ optical detection channel achieved simultaneous monitoring of the degradation process and concentration changes, avoiding the time lag and operational errors introduced by traditional offline sampling analysis. The detection signal can be acquired and processed in real time, with good data continuity and high repeatability, making it particularly suitable for systems with fast reaction rates or easily transformable intermediate products. Furthermore, the fiber optic transmission structure has excellent electromagnetic interference resistance and can operate stably in high-voltage discharge environments, thus ensuring the reliability of the measurement results. Figure 4 As shown.

[0076] The above description is merely a preferred embodiment of this application and is not intended to limit this application. Any modifications, equivalent substitutions, and improvements made within the spirit and principles of this application should be included within the protection scope of this application.

Claims

1. A device for simultaneously measuring the degradation of organic matter by plasma, characterized in that, include: The plasma generating unit includes a high-voltage electrode (15), a grounding electrode, and a dielectric tube (12) disposed between the high-voltage electrode (15) and the grounding electrode. The high-voltage electrode (15) passes through the dielectric tube (12) along the axial direction, and the grounding electrode is disposed outside the dielectric tube (12). The airflow control unit includes a coaxially arranged air chamber (17), a first sleeve (10), and a second sleeve (11). The second sleeve (11) and the first sleeve (10) form a sleeve structure with an annular channel. The medium pipe (12) is disposed inside the first sleeve (10). The air chamber (17) is used to introduce working gas and protective gas, and is connected to the annular channel and the inlet end of the first sleeve (10) through the air outlet end. The outlet ends of the second sleeve (11) and the first sleeve (10) are provided with airflow outlet nozzles (20). The outlet of the airflow outlet nozzles (20) faces the liquid surface of the reaction vessel (9). The air inlet end of the air chamber (17) is connected to the working gas inlet pipe (14) and the protective gas inlet pipe (16), and a spiral flow stabilizer (19) is provided in the air chamber (17) so that the airflow entering from the working gas inlet pipe (14) and the protective gas inlet pipe (16) forms a rotating airflow after flowing through the spiral flow stabilizer (19), and then enters the annular channel through the air outlet end of the air chamber (17); A flow equalization plate (13) is provided between the air outlet end of the air chamber (17) and the inlet end of the annular channel. The gas flow outlet nozzle (20) is a tapered nozzle. The large-diameter end of the gas flow outlet nozzle (20) is connected to the outlet end of the second sleeve (11), and the small-diameter end of the gas flow outlet nozzle (20) faces the center area of ​​the liquid surface of the reaction vessel (9). An infrared optical detection unit is used to construct an infrared optical in-situ detection optical path corresponding to the spatial position of the liquid reaction area, so that infrared light of a specific wavelength passes laterally through the liquid reaction area and the transmitted light power signal is acquired in real time. The data processing unit is used to receive the electrical signal output by the infrared optical detection unit, and to perform signal processing, concentration calculation and result display.

2. The device for simultaneously measuring plasma degradation of organic matter according to claim 1, characterized in that, A discharge gap is formed between the high-voltage electrode (15) and the grounding electrode. The discharge gap is located in the annular channel between the first sleeve (10) and the second sleeve (11) or between the outlet end of the first sleeve (10) and the outlet end of the second sleeve (11).

3. The device for simultaneously measuring plasma degradation of organic matter according to claim 1, characterized in that, The infrared optical detection unit includes an infrared light source (4), an incident optical fiber, a receiving optical fiber, and a photoelectric detection device (3); the infrared light of a specific wavelength emitted by the infrared light source (4) is introduced into one side of the reaction container (9) through the incident optical fiber and passes laterally through the liquid reaction area along a predetermined optical axis; the transmitted light is collected by the receiving optical fiber located on the other side of the reaction container (9) and transmitted to the photoelectric detection device (3).

4. The device for simultaneously measuring plasma degradation of organic matter according to claim 1, characterized in that, The device also includes a dark box (7), in which the plasma generating unit, airflow control unit, infrared optical detection unit and liquid reaction area are all located inside the dark box (7) to form a closed detection space.

5. A method for simultaneously measuring plasma degradation of organic matter, using the apparatus for simultaneously measuring plasma degradation of organic matter as described in any one of claims 1-4, characterized in that, include: The working gas and the protective gas are introduced into the gas chamber (17) through the gas inlet respectively. The gas flow is stabilized and the flow field is reconstructed by the spiral flow stabilizer (19) set inside the gas chamber (17), so that the gas forms a rotating airflow. The gas is guided into the annular channel formed by the first sleeve (10) and the second sleeve (11) coaxially sleeved by the flow equalization plate (13). A high-frequency voltage is applied between the high-voltage electrode (15) and the ground electrode, causing the gas between the high-voltage electrode (15) and the ground electrode to ionize under the condition of medium barrier, forming a low-temperature non-equilibrium plasma. The plasma is then output along the axis through the gas flow outlet nozzle (20) to the surface of the organic pollutant solution contained in the reaction vessel (9), forming a plasma action area near the surface of the liquid. At the same time, by controlling the flow rate and distribution of the gas flow, the surface of the liquid is kept in a low-disturbance state. While the plasma acts on the liquid surface, infrared light of a specific wavelength is introduced into one side of the reaction container (9) through the incident optical fiber, so that the infrared light passes laterally along the predetermined optical axis through the solution area below the liquid surface in the reaction container (9), and is collected by the receiving optical fiber set on the other side of the reaction container (9) and transmitted to the photoelectric detection device (3), and the photoelectric detection device (3) continuously collects the transmitted light power signal.

6. The method for simultaneously measuring plasma degradation of organic matter according to claim 5, characterized in that, The transmitted light power signal collected by the photoelectric detection device (3) is converted into a digital signal after signal amplification and filtering. The embedded processor calculates the concentration of the target organic pollutant in the solution area based on the transmitted light power signal and the pre-established quantitative calibration relationship between light attenuation and organic pollutant concentration.

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