A fiber optic deuterium gas treatment and recycling system and method

Abstract

This invention relates to the field of gas separation device technology, and more particularly to a deuterium gas treatment and recycling system and method for optical fibers. The system includes a deuterium-nitrogen gas supply device, a deuterium gas treatment tank, a vacuum device, a deuterium gas purification device, a recovery storage tank, a detection component, and a control component. The deuterium gas purification device is connected to the outlet of the deuterium gas treatment tank and includes, in sequence, a drying chamber for drying the mixed gas, an oxygen removal chamber for absorbing oxygen from the mixed gas, and a hydrogen removal chamber for absorbing hydrogen from the mixed gas. By incorporating the deuterium gas purification device, this invention dries and removes oxygen and hydrogen from the deuterium-nitrogen mixed gas discharged from the deuterium gas treatment tank, ensuring that the reuse of the deuterium-nitrogen mixed gas does not cause attenuation at 1338nm in the optical fiber. Simultaneously, by incorporating the control and detection components, the deuterium concentration in the deuterium gas treatment tank is adjusted in real time to meet the requirements for optical fiber processing.

Description

Technical Field

[0001] This invention relates to the field of gas separation device technology, and in particular to a fiber optic deuterium gas treatment and recycling system and method. Background Technology

[0002] During the fiber drawing process, some disordered Si-O free radicals are generated. These Si-O free radicals readily react with hydrogen molecules in the air to form Si-OH, which easily causes fiber aging. Deuterium treatment is the final step in fiber manufacturing. Its mechanism is to cause deuterium to react (or combine) with Si-O free radicals to form Si-OD. This Si-OD prevents hydrogen from replacing deuterium, allowing the fiber to withstand long-term corrosion in a hydrogen-containing environment.

[0003] Furthermore, when treating optical fibers with deuterium, the concentration of deuterium in the treatment tank must meet the requirements set by the process. If the deuterium concentration is too low, it will affect the combination effect of deuterium with SiO radicals, thus affecting the formation of Si-OD. Conversely, if the deuterium concentration is too high, it will cause unnecessary waste and may even pose safety hazards. Therefore, it is essential to control the concentration of deuterium in the treatment tank in real time.

[0004] Considering the high cost of deuterium gas, it is often necessary to recover and reuse the deuterium-nitrogen mixture discharged from the deuterium treatment tank in actual production. Patent application number CN202021941962.4 discloses a deuterium gas recovery and treatment device for optical fiber fabrication, specifically disclosing a deuterium gas treatment cabinet. The deuterium gas treatment cabinet is connected to a buffer tank via a control valve. The buffer tank is connected to a drying and purification unit via a control valve. The drying and purification unit is connected to a gas purification device via a control valve. The gas purification device is connected to the deuterium gas treatment cabinet via a recovered gas storage tank. This patent adds a deuterium gas recovery process and a purification unit to the deuterium gas treatment cabinet, enabling the recovery and reuse of emitted deuterium gas. This not only saves deuterium gas resources but also reduces the manufacturing cost of optical fibers. The gas purification device is equipped with a re-purification pipeline to further purify the deuterium gas at lower concentrations, ensuring that the recovered deuterium gas is purified and fully utilized.

[0005] However, the aforementioned patent still has the following problems: the following chemical reactions occur during deuterium gas treatment:

[0006] Si-O··O-Si+2→Si-O-D+DO-Si

[0007] Si-O-H+2D→Si-O-D+HD↑

[0008] 2Si-O-H + 2D → 2Si-O-D + 2H↑

[0009] When recovering and treating the deuterium-nitrogen mixture, the removal of hydrogen generated during the deuterium treatment was not considered to avoid its impact on the attenuation of the optical fiber at 1338nm during reuse. Summary of the Invention

[0010] To address at least one of the aforementioned technical problems, this invention proposes a deuterium gas treatment and recycling system and method for optical fibers. By setting up a deuterium gas purification device, the deuterium-nitrogen mixture discharged from the deuterium gas treatment tank is dried, oxygenated, and dehydrogenated, ensuring that the deuterium-nitrogen mixture will not cause attenuation at 1338nm in the optical fiber when reused. Simultaneously, by setting up control and detection components, the deuterium gas concentration in the deuterium gas treatment tank is adjusted in real time to meet the optical fiber treatment requirements.

[0011] To achieve the above objectives, the present invention adopts the following technical solution:

[0012] This invention provides a fiber optic deuterium gas recycling system, comprising a deuterium-nitrogen gas supply device, a deuterium gas treatment tank, a vacuum pumping device, a deuterium gas purification device, a recovery storage tank, a detection component, and a control component, wherein:

[0013] The outlet of the deuterium-nitrogen gas supply device is connected to the inlet of the deuterium gas treatment tank, and is used to supply deuterium-nitrogen mixed gas to the deuterium gas treatment tank;

[0014] The vacuum pumping device is connected to the deuterium gas treatment tank and is used to evacuate the deuterium gas treatment tank into a vacuum.

[0015] The deuterium purification device is connected to the outlet of the deuterium treatment tank, and includes a drying chamber for drying the mixed gas, an oxygen removal chamber for absorbing oxygen in the mixed gas, and a hydrogen removal chamber for absorbing hydrogen in the mixed gas, which are connected in sequence.

[0016] The recovery storage tank is used to store the mixed gas after being treated by the deuterium purification device. Its inlet is connected to the outlet of the hydrogen removal chamber, and its outlet is connected to the deuterium-nitrogen supply device.

[0017] The detection assembly includes at least a plurality of concentration detectors installed inside the deuterium gas treatment tank, a pressure detector P1 and a temperature detector T1 for detecting the pressure and temperature inside the deuterium gas treatment tank, and a deuterium gas analyzer F1 for detecting the concentration of deuterium gas in the mixed gas entering the deuterium gas treatment tank.

[0018] The control assembly includes at least several electromagnetic pneumatic valves for controlling the opening and closing of pipelines and a gas mass flow controller for measuring and controlling gas flow.

[0019] Preferably, the dehydrogenation chamber is equipped with sponge palladium or colloidal palladium and a heating device for raising the temperature inside the dehydrogenation chamber.

[0020] Preferably, the deuterium-nitrogen gas supply device includes a mixing tank connected to the inlet of the deuterium gas treatment tank, a deuterium gas tank and a first nitrogen gas tank connected to the inlet of the mixing tank; on the pipeline between the outlet of the deuterium gas tank and the inlet of the mixing tank, an electromagnetic pneumatic valve D1, a gas mass flow controller M1 and an electromagnetic pneumatic valve D3 are sequentially arranged, and on the pipeline between the outlet of the first nitrogen gas tank and the inlet of the mixing tank, an electromagnetic pneumatic valve D2, a gas mass flow controller M2 and an electromagnetic pneumatic valve D4 are sequentially arranged.

[0021] Preferably, the deuterium gas treatment tank has multiple inlets, the mixing tank is connected to the multiple inlets of the deuterium gas treatment tank, and electromagnetic pneumatic valves are arranged between the mixing tank and the multiple inlets.

[0022] Preferably, the vacuum pumping device includes a vacuum pump for pumping the gas in the deuterium gas treatment tank and a second nitrogen gas tank for supplementing nitrogen to the deuterium gas treatment tank, and electromagnetic pneumatic valves D6 and D10 are respectively arranged between the deuterium gas treatment tank and the vacuum pump and the second nitrogen gas tank.

[0023] Preferably, electromagnetic pneumatic valves D7 and D8 are respectively arranged between the deuterium gas treatment tank and the drying chamber and between the deoxygenation chamber and the recovery gas storage tank, and a gas mass flow controller M3 and an electromagnetic pneumatic valve D9 are sequentially arranged between the recovery gas storage tank and the mixing tank.

[0024] Preferably, it further includes a PLC control system, and each electromagnetic pneumatic valve, gas mass flow controller, deuterium gas analyzer, concentration detector, temperature detector and pressure detector are all connected to the PLC control system.

[0025] The second aspect of the present invention provides a method for recycling deuterium gas in fiber treatment, which is realized based on the fiber deuterium gas treatment recycling system, and includes the following steps:

[0026] S1, evacuating the deuterium gas treatment tank;

[0027] S2, injecting a deuterium-nitrogen mixture with a deuterium gas concentration c0 meeting the fiber treatment requirements into the deuterium gas treatment tank until the pressure in the deuterium gas treatment tank reaches the set pressure P0, and adjusting the temperature in the deuterium gas treatment tank to the reaction temperature T0;

[0028] S3, during the fiber treatment process, when the detected pressure value P1 in the deuterium gas treatment tank < P0, inject a deuterium-nitrogen mixture into the deuterium gas treatment tank according to the updated control values of each gas mass flow controller in S22 or S24 until P1 = P0;

[0029] S4, after the fiber treatment is completed, the deuterium-nitrogen mixture in the deuterium gas treatment tank is sequentially purified through a drying chamber, a deoxygenation chamber and a dehydro chamber; [[ID={28]]

[0030] S5, the purified deuterium-nitrogen mixture is stored in the recovery storage tank and used to replenish the deuterium-nitrogen mixture to the mixing tank.

[0031] Preferably, S1 includes:

[0032] S11, open the solenoid pneumatic valve D6, start the vacuum pump to evacuate the deuterium treatment tank until the set pressure P0 is reached inside the deuterium treatment tank;

[0033] S12, close the solenoid pneumatic valve D6, open the solenoid pneumatic valve D10, and inject nitrogen into the deuterium treatment tank until the pressure inside the deuterium treatment tank is 0 kPa;

[0034] S13, close the solenoid pneumatic valve D10, open the solenoid pneumatic valve D6, start the vacuum pump to evacuate the deuterium treatment tank again until the set pressure P0 is reached in the deuterium treatment tank, then close the solenoid pneumatic valves D6 and D10.

[0035] Preferably, S2 includes:

[0036] S21, When there is no deuterium-nitrogen mixture in the recovery storage tank, the control value of gas mass flow controller M1 is set to a0 and the control value of gas mass flow controller M2 is set to b0 according to the deuterium concentration c0.

[0037] S22, Based on the deuterium concentration c1 in the deuterium-nitrogen mixture measured by the deuterium analyzer F1, update the control value a1 of the gas mass flow controller M1. Repeat the comparison between c1 and c0 and update the control value a1 until c1 and c0 are equal. The formula for calculating the control value a1 is as follows:

[0038] S23, When there is a mixed gas in the gas storage tank, the control value of gas mass flow controller M1 is set to a2, the control value of gas mass flow controller M2 is set to b2, and the control value of gas mass flow controller M3 is set to b3 according to the deuterium concentration c0.

[0039] S24. Based on the deuterium concentration c2 in the deuterium-nitrogen mixture measured by the deuterium analyzer F1, update the control value a3 of the gas mass flow controller M1. Repeat the comparison between c2 and c0 and update the control value a3 until c2 and c0 are equal. The formula for calculating the control value a3 is as follows:

[0040] Compared with existing technologies, the fiber optic deuterium gas treatment and recycling system and method provided by this invention have the following beneficial effects:

[0041] This invention incorporates a deuterium purification device to dry and absorb oxygen and remove hydrogen from the deuterium-nitrogen mixture discharged from the deuterium treatment tank. This ensures that the deuterium-nitrogen mixture will not cause attenuation at 1338nm in the optical fiber when reused. Simultaneously, a PLC control system enables real-time adjustment of the control and detection components to maintain the deuterium concentration in the treatment tank at the same level as the set concentration. This not only meets the deuterium concentration requirements during optical fiber processing but also saves production costs. Attached Figure Description

[0042] Figure 1 This is a schematic diagram of a fiber optic deuterium gas treatment and recycling system.

[0043] Figure 2 This is a flowchart of a method for recycling deuterium gas in optical fibers. Detailed Implementation

[0044] To enable those skilled in the art to better understand the technical solutions of the present invention, the technical solutions of the present invention will be clearly and completely described below with reference to the accompanying drawings of the embodiments of the present invention. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments of the present invention.

[0045] Example 1

[0046] Please refer to Figure 1 This embodiment provides a fiber optic deuterium gas recycling system, including a deuterium-nitrogen gas supply device, a deuterium gas treatment tank, a vacuum pumping device, a deuterium gas purification device, a recovery storage tank, a detection component, and a control component, wherein:

[0047] The outlet of the deuterium-nitrogen gas supply device is connected to the inlet of the deuterium gas treatment tank, and is used to supply deuterium-nitrogen mixed gas to the deuterium gas treatment tank;

[0048] The vacuum pumping device is connected to the deuterium gas treatment tank and is used to evacuate the deuterium gas treatment tank into a vacuum.

[0049] The deuterium purification device is connected to the outlet of the deuterium treatment tank. It includes a drying chamber for drying the mixed gas, a deoxygenation chamber for absorbing oxygen in the mixed gas, and a dehydrogenation chamber for absorbing hydrogen in the mixed gas, which are connected in sequence.

[0050] The recovery storage tank is used to store the mixed gas after being treated by the deuterium purification device. Its inlet is connected to the outlet of the hydrogen removal chamber, and its outlet is connected to the deuterium-nitrogen supply device.

[0051] The detection assembly includes at least multiple concentration detectors installed inside the deuterium gas treatment tank, a pressure detector P1 and a temperature detector T1 for detecting the pressure and temperature inside the deuterium gas treatment tank, and a deuterium gas analyzer F1 for detecting the concentration of deuterium gas in the mixed gas entering the deuterium gas treatment tank.

[0052] The control components include at least several electromagnetic pneumatic valves for controlling the opening and closing of pipelines and a gas mass flow controller for measuring and controlling gas flow.

[0053] The above implementation, by setting up a deuterium purification device, dries and absorbs oxygen and removes hydrogen from the deuterium-nitrogen mixture discharged from the deuterium treatment tank, ensuring that the deuterium-nitrogen mixture will not cause attenuation at 1338nm in the optical fiber when reused. At the same time, the PLC control system enables real-time adjustment of the control and detection components to control the deuterium concentration in the deuterium treatment tank, ensuring that the deuterium concentration in the deuterium treatment tank is the same as the set concentration. This not only meets the deuterium concentration requirements during optical fiber processing but also saves production costs.

[0054] It should be noted that in the above embodiments, each electromagnetic pneumatic valve, gas mass flow controller, deuterium analyzer, concentration detector, temperature detector, and pressure detector is connected to the PLC control system. The PLC control principle is prior art and will not be elaborated here.

[0055] To ensure sufficient absorption of hydrogen from the deuterium-nitrogen mixture discharged from the deuterium treatment tank, this embodiment includes a sponge palladium or colloidal palladium in the hydrogen removal chamber. This increases the surface area, resulting in a stronger hydrogen absorption capacity. At room temperature, one volume of sponge palladium can absorb 850 volumes of hydrogen; one volume of colloidal palladium can even absorb 1200 volumes of hydrogen.

[0056] In addition, sponge palladium and colloidal palladium can release most of the absorbed hydrogen when heated to 40-50°C. Therefore, a heating mechanism can be installed in the hydrogen removal chamber to increase the temperature inside the chamber, and it can be connected to a hydrogen recovery chamber through pipelines to recover the hydrogen released by the heating.

[0057] In the above embodiments, the deuterium-nitrogen gas supply device includes a mixing tank connected to the inlet of the deuterium gas treatment tank, and a deuterium gas tank and a first nitrogen gas tank connected to the inlet of the mixing tank; an electromagnetic pneumatic valve D1, a gas mass flow controller M1, and an electromagnetic pneumatic valve D3 are sequentially installed on the pipeline between the outlet of the deuterium gas tank and the inlet of the mixing tank, and an electromagnetic pneumatic valve D2, a gas mass flow controller M2, and an electromagnetic pneumatic valve D4 are sequentially installed on the pipeline between the outlet of the first nitrogen gas tank and the inlet of the mixing tank.

[0058] The function of the mixing tank is to mix the deuterium gas from the deuterium gas tank and the first nitrogen gas tank evenly, and to detect whether the concentration of deuterium gas in the deuterium gas mixture meets the requirements of optical fiber processing by a deuterium gas analyzer F1 installed in the pipeline between the mixing tank and the deuterium gas treatment tank.

[0059] To ensure a relatively consistent gas concentration throughout the deuterium treatment tank, the deuterium treatment tank is equipped with multiple air inlets. The mixing tank is connected to the multiple air inlets of the deuterium treatment tank. Electromagnetic pneumatic valves are installed between the mixing tank and the multiple air inlets. Multiple concentration detectors are installed inside the deuterium treatment tank. In this embodiment, concentration detectors F2, F3, F4, and F5 are provided.

[0060] Understandably, when a concentration detector detects that the concentration at a certain point in the deuterium treatment tank is lower than the set concentration, a deuterium-nitrogen mixture can be injected into the deuterium treatment tank through the air inlet at that point, so that the average concentration of deuterium in the deuterium treatment tank is consistent, which is beneficial to the overall deuterium treatment quality of the optical fiber.

[0061] In this embodiment, the vacuum pumping device includes a vacuum pump for extracting gas from the deuterium treatment tank and a second nitrogen tank for replenishing nitrogen to the deuterium treatment tank. Electromagnetic pneumatic valve D6 and electromagnetic pneumatic valve D10 are respectively provided between the deuterium treatment tank, the vacuum pump, and the second nitrogen tank.

[0062] Electromagnetic pneumatic valves D7 and D8 are installed between the deuterium gas treatment tank and the drying chamber, and between the hydrogen removal chamber and the recovery gas storage tank, respectively. A gas mass flow controller M3 and an electromagnetic pneumatic valve D9 are installed between the recovery gas storage tank and the mixing tank.

[0063] Example 2

[0064] This embodiment provides a method for recycling deuterium gas in optical fibers, including the following steps:

[0065] S1, vacuuming the deuterium gas treatment tank;

[0066] In a preferred embodiment, S1 includes:

[0067] S11, open the solenoid pneumatic valve D6, start the vacuum pump to evacuate the deuterium treatment tank until the set pressure P0 is reached inside the deuterium treatment tank;

[0068] S12, close the solenoid pneumatic valve D6, open the solenoid pneumatic valve D10, and inject nitrogen into the deuterium treatment tank until the pressure inside the deuterium treatment tank is 0 kPa;

[0069] S13, close the solenoid pneumatic valve D10, open the solenoid pneumatic valve D6, start the vacuum pump to evacuate the deuterium treatment tank again until the set pressure P0 is reached in the deuterium treatment tank, then close the solenoid pneumatic valves D6 and D10.

[0070] It should be noted that the vacuuming of the deuterium gas treatment tank in steps S11-S13 can be repeated 1-3 times.

[0071] S2, inject a deuterium-nitrogen mixture with a deuterium concentration c0 that meets the requirements of optical fiber processing into the deuterium treatment tank until the pressure inside the deuterium treatment tank reaches the set pressure P0. According to the display of the temperature detector T1, adjust the temperature inside the deuterium treatment tank to the reaction temperature T0.

[0072] In a preferred embodiment, S2 includes:

[0073] S21, When there is no deuterium-nitrogen mixture in the recovery storage tank, open the solenoid pneumatic valves D1, D2, D3 and D4, and set the control value of the gas mass flow controller M1 to a0 and the control value of the gas mass flow controller M2 to b0 according to the deuterium concentration c0.

[0074] S22, Based on the deuterium concentration c1 in the deuterium-nitrogen mixture measured by the deuterium analyzer F1, update the control value a1 of the gas mass flow controller M1. Repeat the comparison between c1 and c0 and update the control value a1 until c1 and c0 are equal. The formula for calculating the control value a1 is as follows:

[0075] S23, When there is a mixed gas in the gas storage tank, open the solenoid pneumatic valves D1, D2, D3, D4 and D9. According to the deuterium concentration c0, set the control value of gas mass flow controller M1 to a2, the control value of gas mass flow controller M2 to b2 and the control value of gas mass flow controller M3 to b3.

[0076] S24. Open the solenoid pneumatic valve D5. Based on the deuterium concentration c2 in the deuterium-nitrogen mixture measured by the deuterium analyzer F1, update the control value a3 of the gas mass flow controller M1. Repeat the comparison of c2 and c0 and update the control value a3 until c2 and c0 are equal. The formula for calculating the control value a3 is as follows:

[0077] It should be noted that, regardless of whether there is a deuterium-nitrogen mixture in the recovery storage tank, in this embodiment, considering that the deuterium concentration in the deuterium-nitrogen mixture is generally lower than the set concentration for fiber optic processing, and also to facilitate adjustment in actual operation, the above-mentioned control of the deuterium concentration in the deuterium treatment tank is adjusted by using pure deuterium gas in the deuterium tank.

[0078] S3. During the optical fiber processing, when the detected pressure value P1 in the deuterium gas treatment tank < P0, inject a deuterium-nitrogen mixed gas into the deuterium gas treatment tank according to the control values of each gas mass flow controller updated in S22 or S24. According to the display of the pressure detector P1, until P1 = P0.

[0079] It should be noted that since the opening degrees of each gas mass flow controller on the pipelines connecting the deuterium gas tank, nitrogen gas tank and the recovery gas storage tank to the gas mixing tank have been calculated and adjusted in S2, therefore, when injecting the deuterium-nitrogen mixed gas into the deuterium gas treatment tank according to the control values of each gas mass flow controller updated in S22 or S24, the deuterium gas concentration in the deuterium gas treatment tank meets the requirements for optical fiber processing.

[0080] Of course, when the detected pressure value P1 in the deuterium gas treatment tank > P0, the PLC control system opens the electromagnetic pneumatic valve D6 to adjust the pressure in the deuterium gas treatment tank.

[0081] S4. After the optical fiber processing is completed, open the electromagnetic pneumatic valve D7, and the deuterium-nitrogen mixed gas in the deuterium gas treatment tank is sequentially purified through the drying chamber, deoxygenation chamber and dehydro chamber;

[0082] S5. Open the electromagnetic pneumatic valve D8, and store the purified deuterium-nitrogen mixed gas into the recovery gas storage tank for supplementing the deuterium-nitrogen mixed gas to the gas mixing tank.

[0083] By setting up the deuterium gas purification device, the present invention conducts drying, oxygen absorption and dehydro treatment on the deuterium-nitrogen mixed gas discharged from the deuterium gas treatment tank, so that when the deuterium-nitrogen mixed gas is reused, it will not cause attenuation effects on the 1338nm of the optical fiber. At the same time, through the PLC control system, the control components and detection components are adjusted in real time to control the deuterium gas concentration in the deuterium gas treatment tank, so that the deuterium gas concentration in the deuterium gas treatment tank is the same as the set concentration, thus not only meeting the requirements of the deuterium gas concentration during the optical fiber processing but also saving the production cost.

[0084] The above is the specific implementation manner of the embodiments of the present invention. It should be noted that for those of ordinary skill in the art, without departing from the principle of the present invention, several improvements and refinements can be made, and these improvements and refinements should also be regarded as the protection scope of this application.

Claims

1. A method for treating and recycling deuterium gas in optical fibers, implemented based on an optical fiber deuterium gas treatment and recycling system, characterized in that... The described optical fiber deuterium gas treatment recycling system includes a deuterium-nitrogen gas supply device, a deuterium gas treatment tank, a vacuum pumping device, a deuterium gas purification device, a recovery gas storage tank, a detection component, and a control component, where: The outlet of the deuterium-nitrogen gas supply device is connected to the inlet of the deuterium gas treatment tank, and is used to supply a deuterium-nitrogen mixed gas to the deuterium gas treatment tank; The vacuum pumping device is connected to the deuterium gas treatment tank and is used to pump the deuterium gas treatment tank into a vacuum; The deuterium gas purification device is connected to the outlet of the deuterium gas treatment tank, and includes a drying chamber connected in sequence for drying the mixed gas, an oxygen removal chamber for absorbing oxygen in the mixed gas, and a hydrogen removal chamber for absorbing hydrogen in the mixed gas; The recovery gas storage tank is used to store the mixed gas treated by the deuterium gas purification device. Its inlet is connected to the outlet of the hydrogen removal chamber, and its outlet is connected to the deuterium-nitrogen gas supply device; The detection component at least includes multiple concentration detectors arranged in the deuterium gas treatment tank, a pressure detector P1 and a temperature detector T1 for detecting the pressure and temperature in the deuterium gas treatment tank, and a deuterium gas analyzer F1 for detecting the deuterium gas concentration in the mixed gas entering the deuterium gas treatment tank; The control component at least includes several electromagnetic pneumatic valves for controlling the opening and closing of pipelines and a gas mass flow controller for measuring and controlling the gas flow rate; The deuterium-nitrogen gas supply device includes a mixing tank connected to the inlet of the deuterium gas treatment tank, a deuterium gas tank and a first nitrogen gas tank connected to the inlet of the mixing tank. An electromagnetic pneumatic valve D1, a gas mass flow controller M1, and an electromagnetic pneumatic valve D3 are sequentially arranged on the pipeline between the outlet of the deuterium gas tank and the inlet of the mixing tank. An electromagnetic pneumatic valve D2, a gas mass flow controller M2, and an electromagnetic pneumatic valve D4 are sequentially arranged on the pipeline between the outlet of the first nitrogen gas tank and the inlet of the mixing tank; A gas mass flow controller M3 and an electromagnetic pneumatic valve D9 are sequentially arranged between the recovery gas storage tank and the mixing tank; The method includes the following steps: S1, evacuating the deuterium gas treatment tank: S2, injecting a deuterium-nitrogen mixed gas with a deuterium gas concentration c0 that meets the requirements of optical fiber treatment into the deuterium gas treatment tank until the pressure in the deuterium gas treatment tank reaches the set pressure P0, and adjusting the temperature in the deuterium gas treatment tank to the reaction temperature T0; The S2 includes: S21, when there is no deuterium-nitrogen mixed gas in the recovery gas storage tank, according to the deuterium gas concentration c0, setting the control value of the gas mass flow controller M1 to a0 and the control value of the gas mass flow controller M2 to b0; S22, Based on the deuterium concentration c1 in the deuterium-nitrogen mixture measured by the deuterium analyzer F1, update the control value a1 of the gas mass flow controller M1. Repeat the comparison between c1 and c0 and update the control value a1 until c1 and c0 are equal. The formula for calculating the control value a1 is as follows: ; S23, when there is mixed gas in the recovery gas storage tank, according to the deuterium gas concentration c0, setting the control value of the gas mass flow controller M1 to a2, the control value of the gas mass flow controller M2 to b2, and the control value of the gas mass flow controller M3 to b3; S24. Based on the deuterium concentration c2 in the deuterium-nitrogen mixture measured by the deuterium analyzer F1, update the control value a3 of the gas mass flow controller M1. Repeat the comparison between c2 and c0 and update the control value a3 until c2 and c0 are equal. The formula for calculating the control value a3 is as follows: ; S3, during the optical fiber treatment process, when the detected pressure value P1 in the deuterium gas treatment tank < P0, inject a deuterium-nitrogen mixed gas into the deuterium gas treatment tank according to the updated control values of each gas mass flow controller in S22 or S24 until P1 = P0; S4, after the optical fiber treatment is completed, the deuterium-nitrogen mixed gas in the deuterium gas treatment tank is sequentially purified through the drying chamber, the oxygen removal chamber, and the hydrogen removal chamber; S5, the purified deuterium-nitrogen mixture is stored in the recovery storage tank and used to replenish the deuterium-nitrogen mixture to the mixing tank.

2. The method for treating and recycling deuterium gas in optical fibers according to claim 1, characterized in that, S1 includes: S11, open the solenoid pneumatic valve D6, start the vacuum pump to evacuate the deuterium treatment tank until the set pressure P0 is reached inside the deuterium treatment tank; S12, Close the solenoid pneumatic valve D6, open the solenoid pneumatic valve D10, and inject nitrogen into the deuterium treatment tank until the pressure inside the deuterium treatment tank reaches 0 kPa; S13, close the solenoid pneumatic valve D10, open the solenoid pneumatic valve D6, start the vacuum pump to evacuate the deuterium treatment tank again until the set pressure P0 is reached in the deuterium treatment tank, then close the solenoid pneumatic valves D6 and D10.

3. The method for treating and recycling deuterium gas in optical fibers according to claim 2, characterized in that, The dehydrogen removal chamber is equipped with sponge palladium or colloidal palladium and a heating device for raising the temperature inside the dehydrogenation chamber.

4. The method for treating and recycling deuterium gas in optical fibers according to claim 3, characterized in that, The deuterium gas treatment tank is provided with multiple air inlets, and the gas mixing tank is connected to the multiple air inlets of the deuterium gas treatment tank. Electromagnetic pneumatic valves are provided between the gas mixing tank and the multiple air inlets.

5. The method for treating and recycling deuterium gas in optical fibers according to claim 4, characterized in that, The vacuum pumping device includes a vacuum pump for extracting gas from the deuterium treatment tank and a second nitrogen tank for replenishing nitrogen to the deuterium treatment tank. Electromagnetic pneumatic valves D6 and D10 are respectively provided between the deuterium treatment tank, the vacuum pump, and the second nitrogen tank.

6. The method for treating and recycling deuterium gas in optical fibers according to claim 5, characterized in that, Electromagnetic pneumatic valves D7 and D8 are respectively installed between the deuterium gas treatment tank and the drying chamber, and between the hydrogen removal chamber and the recovery gas storage tank.

7. The method for treating and recycling deuterium gas in optical fibers according to claim 6, characterized in that, It also includes a PLC control system, and each electromagnetic pneumatic valve, gas mass flow controller, deuterium analyzer, concentration detector, temperature detector, and pressure detector is connected to the PLC control system.

Images