Phosphorane mixed gas purification and recovery system and method thereof

Abstract

The system comprises a control pipeline assembly, a gas-liquid separation cold trap and a recovery cold tank, the gas-liquid separation cold trap is provided with a feeding pipe and a discharging pipe, the feeding pipe is communicated with the other end of the control pipeline assembly to receive the phosphine mixed gas in a torpedo car, and the discharging pipe is communicated with the control pipeline assembly to receive the phosphine mixed gas in the torpedo car; the gas-liquid separation cold trap is used for refrigerating the received phosphorane mixed gas in the torpedo car to obtain liquid phosphorane and non-condensable gas, the gas-liquid separation cold trap is used for liquefying phosphorane in the phosphorane mixed gas, the non-condensable gas is discharged through the exhaust pipeline, and meanwhile, the recovery bottle is used for recovering and storing the phosphorane. Meanwhile, spiral refrigeration channels are arranged outside the recovery bottle and the recovery cold tank, so that vortex can be generated when a gaseous refrigeration medium performs water bath refrigeration on the recovery bottle, the heat exchange refrigeration efficiency is improved, and the heat exchange efficiency of the recovery bottle is improved by utilizing the pressure of a gaseous refrigeration medium column on the inner wall of a first heat exchange channel on the recovery bottle; therefore, the recovery bottle is more stable during phosphorane recovery and does not shake.

Description

Technical Field

[0001] This application relates to the technical field of phosphine recovery, and in particular to a phosphine mixed gas purification and recovery system and method thereof. Background Art

[0002] With the increasing demand in the market, currently, the large package form of phosphine uses torpedo trucks. After the torpedo trucks return to the factory, usually to ensure the quality of the next filling, gas companies will usually process all the residual gas through the tail gas treatment device. Existing phosphine can be safely transported and stored in appropriate containers, such as gas cylinders. However, shaking may increase the pressure of the gas, thereby increasing the risk of leakage or explosion. Therefore, when handling phosphine, strict safety procedures should be followed to avoid unnecessary shaking and ensure the integrity and safety of the container.

[0003] For phosphine, there are many ways of tail gas treatment, including: water absorption method, chemical oxidation method, activated carbon adsorption method, ozone oxidation method, combustion method, dry tail gas treatment equipment, and multi-stage washing system. Nowadays, the general phosphine tail gas treatment uses dry tail gas treatment equipment containing phosphine adsorbent. The dry tail gas processor mainly adsorbs phosphine through the adsorbent to meet the national emission standards.

[0004] However, in the above-mentioned tail gas treatment methods, since there is about 5%wt (6 Kg) of phosphine residual gas in the torpedo truck, it is too wasteful for phosphine resources. In addition, there are non-condensable gases in the existing phosphine during recovery treatment, and the recovered purity is not high. Summary of the Invention

[0005] This application provides a phosphine mixed gas purification and recovery system, which can solve the problems of complex existing phosphine recovery methods, low recovery efficiency, and low purity of recovered phosphine.

[0006] The technical solution of this application is as follows: A phosphine mixed gas purification and recovery system for recovering phosphine, including: A control pipeline assembly, one end of which is connected to the torpedo truck; A gas-liquid separation cold trap, which is provided with a feed pipe and a discharge pipe. The feed pipe is connected to the other end of the control pipeline assembly to receive the phosphine mixed gas in the torpedo truck. The gas-liquid separation cold trap is used to refrigerate the received phosphine mixed gas in the torpedo truck to obtain liquid phosphine and non-condensable gas; Recovery cold tank, a recovery bottle communicated with the discharge pipe is arranged in the recovery cold tank for recovering and storing gaseous phosphine obtained by processing through a gas-liquid separation cold trap. A spiral first heat exchange channel is arranged on the outer part of the recovery bottle along its own length direction. A spiral second heat exchange channel is arranged on the inner wall of the recovery cold tank along its own height direction. The second heat exchange channel has the same spiral direction as the first heat exchange channel. The first heat exchange channel and the second heat exchange channel are butted to form a refrigeration channel, and a gaseous refrigeration medium is arranged inside the refrigeration channel.

[0007] By adopting the above scheme, the phosphine in the phosphine mixed gas is liquefied by using a gas-liquid separation cold trap, and the non-condensable gas is discharged through an exhaust pipeline. At the same time, the phosphine is recovered and stored by using a recovery bottle. At the same time, by arranging a spiral refrigeration channel outside the recovery bottle and the recovery cold tank, when the gaseous refrigeration medium performs water bath refrigeration on the recovery bottle, a vortex can be generated, improving the heat exchange and refrigeration efficiency. At the same time, by using the pressure of the gaseous refrigeration medium column on the inner wall of the first heat exchange channel on the recovery bottle, the recovery bottle is more stable when recovering phosphine and will not shake.

[0008] In one embodiment of the present application, the control pipeline assembly includes: A feed pipeline, one end of the feed pipeline is communicated with the torpedo car, and the other end is communicated with the feed pipe; An exhaust pipeline, an air outlet pipe communicated with the gas-liquid separation cold trap is arranged on the gas-liquid separation cold trap. One end of the exhaust pipeline is communicated with the air outlet pipe, and the other end is communicated with the tail gas treatment device; A replacement pipeline, a replacement manual diaphragm valve, a replacement one-way valve, a replacement pressure-reducing valve with a pressure gauge and a replacement pneumatic diaphragm valve are sequentially arranged on the replacement pipeline along the air inlet direction. One end of the replacement pipeline is communicated with the feed pipe through a detection pipeline, and the other end is communicated with a helium gas cylinder. The replacement pipeline can introduce helium gas into the gas-liquid separation cold trap to discharge the air in the gas-liquid separation cold trap; A vacuum pipeline, a vacuum pneumatic diaphragm valve, a vacuum pressure gauge and a vacuum manual diaphragm valve are sequentially arranged on the vacuum pipeline along the air outlet direction. One end of the vacuum pipeline is communicated with the feed pipe through a detection pipeline, and a vacuum pump is arranged at the other end and is communicated with the tail gas treatment device. The vacuum pipeline is used for pumping out the helium gas in the gas-liquid separation cold trap; An emptying pipeline, an air exhaust pneumatic diaphragm valve, an emptying one-way valve and an emptying manual diaphragm valve are sequentially arranged on the emptying pipeline along the air outlet direction. One end of the emptying pipeline is communicated with the feed pipe through a detection pipeline and is used for discharging the remaining gas inside the control pipeline assembly.

[0009] By adopting the above solution, before introducing phosphine, helium is introduced into the gas-liquid separation cold trap in advance by using a replacement pipeline, so as to discharge the air in the gas-liquid separation cold trap and the feed pipeline from the system. After discharging the helium, the introduced helium in the gas-liquid separation cold trap is discharged by using a vacuum pipeline, so that a negative pressure is formed in the gas-liquid separation cold trap. When introducing the phosphine mixture gas subsequently, the phosphine mixture gas can automatically enter the gas-liquid separation cold trap and will not come into direct contact with air, avoiding the possibility of phosphine explosion.

[0010] In one embodiment of the present application, a plurality of feed pressure reducing valves are arranged on the feed pipeline. The plurality of feed pressure reducing valves are sequentially arranged at intervals along the intake direction on the feed pipeline. A feed pressure gauge corresponding to each feed pressure reducing valve is arranged on the outlet side of each feed pressure reducing valve. The plurality of feed pressure gauges are all arranged on the feed pipeline and are used to detect the gas pressure after being reduced by the corresponding feed pressure reducing valve. A feed check valve is arranged at one end of the feed pipeline close to the gas-liquid separation cold trap.

[0011] By adopting the above solution, by arranging a plurality of feed pressure reducing valves in the feed pipeline, the high-pressure phosphine mixture gas inside the torpedo vehicle is gradually reduced in pressure by the plurality of feed pressure reducing valves for multiple times, thus avoiding the high-pressure impact of the phosphine mixture gas on other valve bodies inside the control pipeline assembly and improving the protection ability of the valve bodies inside the control pipeline assembly.

[0012] In one embodiment of the present application, an exhaust pneumatic diaphragm valve, an exhaust pressure gauge reducing valve and an exhaust manual diaphragm valve are sequentially arranged on the exhaust pipeline along the gas outlet direction. One end of the exhaust pipeline is communicated with the outlet pipe, and the other end is communicated with the tail gas treatment device. A pressure relief bypass is also arranged on one side of the exhaust pipeline.

[0013] By adopting the above solution, by setting the exhaust manual diaphragm valve to be normally open and controlling the opening and closing of the exhaust pneumatic diaphragm valve, the on-off between the device exhaust pipeline and the gas-liquid separation cold trap is realized to discharge the non-condensable gas. At the same time, by adopting the double-valve control method, the safety of the exhaust pipeline can be effectively improved.

[0014] In one embodiment of the present application, a pressure relief manual diaphragm valve and a pressure relief proportional unloading valve are sequentially arranged on the pressure relief bypass along the gas outlet direction. One end of the pressure relief bypass is communicated with the pipeline between the exhaust pipeline and the outlet pipe, and the other end is communicated with the tail gas treatment device. A first pressure detection component is also arranged at the intake end of the pressure relief bypass and is used to detect the gas pressure on the pressure relief bypass in real time.

[0015] By adopting the above solution, by setting up a pressure relief bypass, when discharging non-condensable gas, if special circumstances are encountered and the internal pressure of the system is too high, the pressure relief bypass can be opened, so as to assist the exhaust pipeline to discharge gas together, avoid the internal pressure of the system from being too high, prevent the occurrence of safety accidents, and improve the safety performance of the device during use.

[0016] In one embodiment of the present application, there are two detection pneumatic diaphragm valves, a second pressure detection component and a vacuum gauge component arranged at intervals on the detection pipeline. The second pressure detection component is located between the two detection pneumatic diaphragm valves and is used to monitor and measure the gas pressure in the detection pipeline. The vacuum gauge component is located at one end of the detection pipeline close to the evacuation pipeline. An inlet pneumatic diaphragm valve is provided on the feed pipe. One end of the detection pipeline is communicated with the feed pipe, and the other end is respectively communicated with the replacement pipeline, the vacuum pipeline and the exhaust pipeline.

[0017] By adopting the above solution, by setting up a detection pipeline respectively communicated with the replacement pipeline, the vacuum pipeline and the exhaust pipeline, when the gas flows through the detection pipeline, the positive or negative pressure inside the detection pipeline is detected by the second pressure detection component and the vacuum machine component, so that the pressure inside the system is always kept within a controllable range, further improving the safety performance of the system during use.

[0018] In one embodiment of the present application, the recovery cold tank further includes: A weighing base, and the recovery cold tank is assembled on one side of the upper end of the weighing base; A refrigeration container, which is assembled on the other side of the upper end of the weighing base. The refrigeration container is provided with a plurality of refrigeration sheets. The inlet and outlet of the refrigeration container are respectively communicated with both ends of the second heat exchange channel; An air pump, which is assembled on the weighing base and is located on one side of the refrigeration container, and is used to drive the gaseous refrigeration medium to circulate inside the recovery cold tank.

[0019] By adopting the above solution, when using the recovery bottle to recover phosphine, as phosphine continuously enters the inside of the recovery bottle, the weighing base can measure the weight of the recovery bottle in real time. When the weight reaches the preset value, that is, when the phosphine recovery is completed, the recovery bottle can be removed from the device at this time. At the same time, the air pump can drive the gaseous refrigeration medium that has been cooled by the refrigeration sheets inside the refrigeration container to circulate, improving the flow rate of the gaseous refrigeration medium, and thus accelerating the heat exchange speed.

[0020] In one embodiment of the present application, the phosphine mixed gas purification and recovery system further includes a recovery pipeline. Both ends of the recovery pipeline are respectively communicated with the discharge pipe and the recovery bottle. A recovery pneumatic diaphragm valve and a recovery manual diaphragm valve are sequentially arranged on the recovery pipeline along the intake direction.

[0021] By adopting the above solution, the purified phosphine gas is transported to the recovery bottle for recovery through the recovery pipeline, and at the same time, the double-valve control method is adopted to ensure the safety of the recovery pipeline during use.

[0022] In one embodiment of the present application, the phosphine gas mixture purification and recovery system further includes a pressure measurement pipeline. One end of the pressure measurement pipeline is communicated with the detection pipeline, and the other end is communicated with the pipeline between the recovery pneumatic diaphragm valve and the recovery manual diaphragm valve. A pressure measurement pneumatic diaphragm valve and a third pressure transmitter are provided on the pressure measurement pipeline.

[0023] By adopting the above solution, by setting the pressure measurement pipeline, the gas pressure between the recovery pneumatic diaphragm valve and the recovery manual diaphragm valve on the recovery pipeline can be detected in real time, thereby improving the controllability of the gas before reaching the recovery bottle.

[0024] The present invention also relates to a method for purifying and recovering a phosphine gas mixture. The technical solution is as follows: Using the phosphine gas mixture purification and recovery system to purify and recover the phosphine gas mixture, including the following steps: Step 1: Place the recovery bottle in the recovery cold tank and connect it to the recovery pipeline, and pre-cool the gas-liquid separation cold trap to -50°C; Step 2: Introduce the helium gas inside the helium gas cylinder into the gas-liquid separation cold trap through the replacement pipeline to extrude the air in the gas-liquid separation cold trap; Step 3: Use the vacuum pipeline to extract the helium gas in the gas-liquid separation cold trap until the gas-liquid separation cold trap is vacuum; Step 4: Use the feed pipeline to reduce the pressure of the phosphine gas mixture in the torpedo car to 0.5 Mpa and introduce it into the gas-liquid separation cold trap. At the same time, cool the gas-liquid separation cold trap to -90°C and open the exhaust pipeline. The phosphine liquefies, and the non-condensable gas is discharged from the gas-liquid separation cold trap along the exhaust pipeline to obtain liquid phosphine; Step 5: Cool the gas-liquid separation cold trap to -100°C and continuously input the phosphine gas mixture to make the pressure in the gas-liquid separation cold trap 0.5 bar higher than one atmospheric pressure until the liquid phosphine recovery is completed; Step 6: Close the feed pipeline and the exhaust pipeline, stop cooling the gas-liquid separation cold trap and let it stand until room temperature. The liquid phosphine vaporizes as the temperature rises, and the pressure inside the gas-liquid separation cold trap rises to obtain purified phosphine; Step 7: Use the recovery cold tank to pre-cool the recovery bottle to -50°C, and use the recovery pipeline to introduce the purified phosphine into the recovery bottle for internal storage and recovery; Step 8: Calculate the purified phosphine inside the recovery bottle through the weighing base. After reaching the specified weight, close the recovery cold tank and remove the recovery bottle.

[0025] By adopting the above solution, through the use of a phosphine mixed gas purification and recovery system to control the temperature and pressure of each part, the phosphine mixed gas is subjected to helium filling protection, liquefaction separation, and re-vaporization preservation, and the purification and transportation of phosphine gas are realized by using the air pressure difference.

[0026] In summary, the present application includes at least one of the following beneficial technical effects: 1. By using a gas-liquid separation cold trap to liquefy the phosphine in the phosphine mixed gas and discharging the non-condensable gas through an exhaust pipeline, and by pre-introducing helium, the air in the system pipeline and the gas-liquid separation cold trap is discharged, thereby improving the safety and stability of the device when purifying and recovering phosphine gas and avoiding the explosion caused by the contact of air with phosphine.

[0027] 2. By allowing the liquefied phosphine to stand still and return to room temperature, the volume expansion generated during its vaporization forms air pressure, enabling the gaseous phosphine to automatically flow into the recovery bottle. Without additional power input, the purified phosphine can be automatically recovered into the recovery bottle.

[0028] 3. By setting multiple inlet pressure reducing valves in cooperation with an inlet pressure gauge, when the phosphine mixed gas enters the system through the inlet pipeline, through multi-stage pressure reduction, the impact damage to each valve body in the system caused by the high-pressure phosphine mixed gas during movement in the system is avoided. 4. By setting a recovery bottle and a recovery cold tank, when pre-cooling the recovery bottle and recovering phosphine, the gaseous refrigeration medium can flow spirally in the refrigeration channel composed of the first heat exchange channel and the second heat exchange channel to form a vortex, thereby increasing the heat exchange speed of the gaseous refrigeration medium. At the same time, the flow rate of the gaseous refrigeration medium increases, and the pressure of the gaseous refrigeration medium on the first heat exchange channel also increases. Furthermore, the device can improve the placement stability of the recovery bottle without additional clamping devices, preventing the recovery bottle from shaking randomly. BRIEF DESCRIPTION OF THE DRAWINGS

[0029] Figure 1 is a schematic diagram of a phosphine mixed gas purification and recovery system provided in an embodiment of the present application when helium is introduced; Figure 2 is a schematic diagram of a phosphine mixed gas purification and recovery system provided in an embodiment of the present application when helium is extracted until it is vacuum; Figure 3 is a schematic diagram of a phosphine mixed gas purification and recovery system provided in an embodiment of the present application when phosphine mixed gas is introduced and non-condensable gas is discharged; Figure 4 is a schematic diagram of a phosphine mixed gas purification and recovery system provided in an embodiment of the present application when recovering phosphine gas; Figure 5It is a schematic diagram of the exhaust pipe line of a phosphine mixed gas purification and recovery system provided in an embodiment of the present application; Figure 6 It is a schematic diagram of the feed pipe line of a phosphine mixed gas purification and recovery system provided in an embodiment of the present application; Figure 7 It is a schematic diagram of the evacuation pipe line of a phosphine mixed gas purification and recovery system provided in an embodiment of the present application; Figure 8 It is a schematic diagram of the replacement pipe line of a phosphine mixed gas purification and recovery system provided in an embodiment of the present application; Figure 9 It is a schematic diagram of the vacuum pipe line of a phosphine mixed gas purification and recovery system provided in an embodiment of the present application; Figure 10 It is a schematic diagram of the detection pipe line of a phosphine mixed gas purification and recovery system provided in an embodiment of the present application; Figure 11 It is a front sectional view of the first heat exchange channel of the detection pipe line of a phosphine mixed gas purification and recovery system provided in an embodiment of the present application; Figure 12 It is a front view of the first heat exchange channel of the detection pipe line of a phosphine mixed gas purification and recovery system provided in an embodiment of the present application.

[0030] Description of the reference numerals: 1. Gas-liquid separation cold trap; 11. Feed pipe; 111. Feed pneumatic diaphragm valve; 12. Outlet gas pipe; 13. Discharge pipe; 14. Refrigeration interlayer; 15. Refrigeration coil; 2. Control pipeline assembly; 21. Feed pipeline; 211. Feed pressure reducing valve; 212. Feed pressure gauge; 213. Feed check valve; 22. Exhaust pipeline; 221. Exhaust pneumatic diaphragm valve; 222. Exhaust pressure reducing valve with pressure gauge; 223. Exhaust manual diaphragm valve; 23. Replacement pipeline; 231. Replacement manual diaphragm valve; 232. Replacement check valve; 233. Replacement pressure reducing valve with pressure gauge; 234. Replacement pneumatic diaphragm valve; 24. Vacuum pipeline; 241. Vacuum pneumatic diaphragm valve; 242. Vacuum pressure gauge; 243. Vacuum manual diaphragm valve; 25. Drainage pipeline; 251. Drainage pneumatic diaphragm valve; 252. Drainage check valve; 253. Drainage manual diaphragm valve; 26. Pressure relief bypass; 261. Pressure relief manual diaphragm valve; 262. Pressure relief proportional unloading valve; 263. First pressure detection assembly; 2631. First pressure transmitter; 2632. First manual diaphragm valve; 27. Detection pipeline; 271. Detection pneumatic diaphragm valve; 272. Second pressure detection assembly; 2721. Second pressure transmitter; 2722. Second manual diaphragm valve; 273. Vacuum gauge assembly; 2731. Vacuum gauge; 2732. Vacuum manual valve; 28. Recovery pipeline; 281. Recovery pneumatic diaphragm valve; 282. Recovery manual diaphragm valve; 29. Pressure measurement pipeline; 291. Pressure measurement pneumatic diaphragm valve; 292. Third pressure transmitter; 3. Recovery cold tank; 31. Recovery bottle; 32. First heat exchange channel; 33. Second heat exchange channel; 34. Refrigeration channel; 35. Weighing base; 36. Refrigeration container; 37. Air pump. Detailed implementation manners

[0031] The following further elaborates on a phosphine gas mixture purification and recovery system provided by this application in conjunction with the attached Figures 1 - 12 drawings.

[0032] Please refer to Figure 3 , Figure 11 and Figure 12, a phosphine mixed gas purification and recovery system provided in an embodiment of the present application, which recovers phosphine, includes: a control pipeline assembly 2, a gas-liquid separation cold trap 1, and a recovery cold tank 3. One end of the control pipeline assembly 2 is connected to a torpedo car. The gas-liquid separation cold trap 1 is provided with a feed pipe 11 and a discharge pipe 13 that are communicated with the gas-liquid separation cold trap 1. The feed pipe 11 is communicated with the other end of the control pipeline assembly 2 to receive the phosphine mixed gas in the torpedo car. The gas-liquid separation cold trap 1 is used to cool the received phosphine mixed gas in the torpedo car to obtain liquid phosphine and non-condensable gas. A recovery bottle 31 communicated with the discharge pipe 13 is arranged in the recovery cold tank 3. After the gas-liquid separation cold trap 1 cools the phosphine mixed gas to obtain liquid phosphine, its temperature is restored to room temperature by standing still, so as to obtain gaseous phosphine. A recovery bottle 31 communicated with the discharge pipe 13 is arranged in the recovery cold tank 3, which is used to recover and store the gaseous phosphine obtained after being processed by the gas-liquid separation cold trap 1. A spiral first heat exchange channel 32 is arranged along the length direction of the outside of the recovery bottle 31. A spiral second heat exchange channel 33 is arranged along the height direction of the inner wall of the recovery cold tank 3. The spiral direction of the second heat exchange channel 33 is the same as that of the first heat exchange channel 32. The first heat exchange channel 32 and the second heat exchange channel 33 are butted to form a refrigeration channel 34. A gaseous refrigeration medium is arranged inside the refrigeration channel 34. When the gaseous refrigeration medium passes through the refrigeration channel 34, while pre-cooling the recovery bottle 31, it makes the recovery bottle 31 not shake when recovering phosphine.

[0033] Wherein, a rubber sleeve (not shown in the figure) coaxially sleeved outside the recovery bottle 31 can be arranged outside the recovery bottle 31. By using the interference fit between the rubber sleeve and the recovery cold tank 3, when the recovery bottle is placed in the recovery cold tank 3, the rubber sleeve can deform due to the extrusion of the recovery cold tank 3, thereby improving the sealing performance between the first heat exchange channel 32 and the second heat exchange channel 33. At the same time, it can also improve the stability of the recovery bottle when placed in the recovery cold tank 3. Among them, the material of the rubber sleeve can be fluoropolyether rubber or cis-butadiene rubber.

[0034] Wherein, a first mark (not shown in the figure) can be arranged outside the recovery bottle 31, and a second mark (not shown in the figure) corresponding to the first mark can be arranged outside the recovery cold tank 3. When placing the recovery bottle 31, by aligning the first mark with the second mark, the position angle of the first heat exchange channel 32 and the second heat exchange channel 33 can be accurately found, so that the two can be accurately butted.

[0035] Wherein, a liquid level gauge and a thermometer are also arranged on the gas-liquid separation cold trap 1, which are respectively used to measure the liquid level height and temperature in the gas-liquid separation cold trap 1; Among them, when discharging the phosphine mixture inside the torpedo car, since the air pressure of the phosphine mixture inside the torpedo car is 5-6 times higher than one standard atmospheric pressure, when the gas-liquid separation cold trap 1 introduces the phosphine mixture inside the torpedo car into the device, due to the pressure difference between the two, the phosphine mixture is sucked into the gas-liquid separation cold trap 1.

[0036] In this embodiment, the gas-liquid separation cold trap 1 includes a refrigeration interlayer 14 and a refrigeration coil 15. The refrigeration coil 15 is arranged in the inner cavity of the gas-liquid separation cold trap 1, and the refrigeration interlayer 14 is arranged outside the gas-liquid separation cold trap 1. Refrigerant is introduced into both the refrigeration interlayer 14 and the refrigeration coil 15 to cool down the gas-liquid separation cold trap 1.

[0037] Please refer to Figure 1 、 Figure 7 、 Figure 8 and Figure 9 As shown in, the control pipeline assembly 2 includes: a feed pipeline 21, an exhaust pipeline 22, a replacement pipeline 23, a vacuum pipeline 24, and an evacuation pipeline 25. One end of the feed pipeline 21 is connected to the torpedo car, and the other end is connected to the feed pipe 11. An air outlet pipe 12 communicating with the gas-liquid separation cold trap 1 is provided on the gas-liquid separation cold trap 1. One end of the exhaust pipeline 22 is connected to the air outlet pipe 12, and the other end is connected to the tail gas treatment device. A replacement manual diaphragm valve 231, a replacement one-way valve 232, a replacement pressure-reducing valve with a pressure gauge 233, and a replacement pneumatic diaphragm valve 234 are sequentially arranged on the replacement pipeline 23 along the intake direction. One end of the replacement pipeline 23 is connected to the feed pipe 11 through a detection pipeline 27, and the other end is connected to a helium gas cylinder. The replacement pipeline 23 can introduce helium gas into the gas-liquid separation cold trap 1 to discharge the air in the gas-liquid separation cold trap 1. A vacuum pneumatic diaphragm valve 241, a vacuum pressure gauge 242, and a vacuum manual diaphragm valve 243 are sequentially arranged on the vacuum pipeline 24 along the air outlet direction. One end of the vacuum pipeline 24 is connected to the feed pipe 11 through a detection pipeline 27, and a vacuum pump is provided at the other end and is connected to the tail gas treatment device. The vacuum pipeline 24 is used to extract the helium gas in the gas-liquid separation cold trap 1. An exhaust air pneumatic diaphragm valve 251, an exhaust air one-way valve 252, and an exhaust air manual diaphragm valve 253 are sequentially arranged on the evacuation pipeline 25 along the air outlet direction. One end of the evacuation pipeline 25 is connected to the feed pipe 11 through a detection pipeline 27 and is used to discharge the remaining gas inside the control pipeline assembly 2. By previously introducing helium gas into the gas-liquid separation cold trap 1 through the replacement pipeline 23 to displace the air in the system and using the vacuum pipeline 24 to discharge the helium gas introduced into the gas-liquid separation cold trap 1, it is ensured that when the phosphine mixture enters the gas-liquid separation cold trap 1, it will not come into direct contact with air at the same time.

[0038] In this embodiment, the tail gas treatment device can be a dry tail gas treatment device, and an adsorbent for adsorbing phosphine is provided inside it.

[0039] Please refer to Figure 6 , a plurality of inlet pressure reducing valves 211 are provided on the inlet pipeline 21. The plurality of inlet pressure reducing valves 211 are arranged at intervals in sequence along the gas inlet direction on the inlet pipeline 21. On the outlet side of each inlet pressure reducing valve 211, there is an inlet pressure gauge 212 corresponding to the inlet pressure reducing valve 211 one by one. The plurality of inlet pressure gauges 212 are all arranged on the inlet pipeline 21 and are used to detect the gas pressure after being reduced by the corresponding inlet pressure reducing valve 211. An inlet check valve 213 is provided at one end of the inlet pipeline 21 close to the gas-liquid separation cold trap 1. By the mutual cooperation of the plurality of inlet pressure reducing valves 211, the air pressure when the phosphine mixed gas enters the system is reduced, and other valve bodies in the system are protected.

[0040] Please refer to Figure 5 , an exhaust pneumatic diaphragm valve 221, an exhaust pressure gauge reducing valve 222 and an exhaust manual diaphragm valve 223 are arranged in sequence along the gas outlet direction on the exhaust pipeline 22. One end of the exhaust pipeline 22 is communicated with the outlet pipe 12, and the other end is communicated with the tail gas treatment device. A pressure relief bypass 26 is also provided on one side of the exhaust pipeline 22. By means of double-valve control, it is ensured that when discharging non-condensable gas, even if the exhaust pneumatic diaphragm valve 221 fails, the on-off of the exhaust pipeline 22 can still be manually realized.

[0041] Please refer to Figure 5 , a pressure relief manual diaphragm valve 261 and a pressure relief proportional unloading valve 262 are arranged in sequence along the gas outlet direction on the pressure relief bypass 26. One end of the pressure relief bypass 26 is communicated with the pipeline between the exhaust pipeline 22 and the outlet pipe 12, and the other end is communicated with the tail gas treatment device. A first pressure detection component 263 is also provided at the air inlet end of the pressure relief bypass 26 and is used to detect the gas pressure on the pressure relief bypass 26 in real time. When the system pressure is too high, the pressure in the system can be timely discharged through the pressure relief bypass 26 to avoid the occurrence of safety accidents caused by excessive system pressure.

[0042] In this embodiment, the first pressure detection component 263 includes a first pressure transmitter 2631 and a first manual diaphragm valve 2632. The first pressure transmitter 2631 is communicated with the pressure relief bypass 26, and the first manual diaphragm valve 2632 is arranged on the pipeline where the first pressure transmitter 2631 is communicated with the pressure relief bypass 26 Please refer to Figure 10, there are two pneumatic diaphragm valves for detection 271, a second pressure detection component 272 and a vacuum gauge component 273 arranged at intervals on the detection pipeline 27. The second pressure detection component 272 is located between the two pneumatic diaphragm valves for detection 271 and is used to monitor and measure the gas pressure on the detection pipeline 27. The vacuum gauge component 273 is located at one end of the detection pipeline 27 close to the evacuation pipeline 25. An inlet pneumatic diaphragm valve 111 is provided on the feed pipe 11. One end of the detection pipeline 27 is communicated with the feed pipe 11, and the other end is respectively communicated with the replacement pipeline 23, the vacuum pipeline 24 and the exhaust pipeline 22. By setting the second pressure detection component 272 and the vacuum gauge component 273, the device can perform two-way detection of positive pressure and negative pressure on the gas in the detection pipeline 27, ensuring the use safety performance of the system.

[0043] In this embodiment, the second pressure detection component 272 includes a second pressure transmitter 2721 and a second manual diaphragm valve 2722. The second pressure transmitter 2721 is communicated with the detection pipeline 27, and the second manual diaphragm valve 2722 is arranged on the pipeline where the second pressure transmitter 2721 is communicated with the detection pipeline 27. The vacuum gauge component 273 includes a vacuum gauge 2731 and a vacuum manual valve 2732. The vacuum gauge 2731 is communicated with the detection pipeline 27, and the vacuum manual valve 2732 is arranged on the pipeline where the vacuum gauge 2731 is communicated with the detection pipeline 27.

[0044] Please refer to Figures 1 to 4 , the recovery cold tank 3 further includes: a weighing base 35, a refrigeration container 36 with a gaseous refrigeration medium inside, and an air pump 37. The recovery cold tank 3 is assembled on one side of the upper end of the weighing base 35, the refrigeration container 36 is assembled on the other side of the upper end of the weighing base 35. A plurality of refrigeration fins (not shown in the figure) are provided on the refrigeration container 36. The inlet and outlet of the refrigeration container 36 are respectively communicated with both ends of the second heat exchange channel 33. The air pump 37 is assembled on the weighing base 35 and is located on one side of the refrigeration container 36, and is used to drive the gaseous refrigeration medium to circulate inside the recovery cold tank 3. By using the refrigeration fins to cool the refrigeration container 36, the gaseous refrigeration medium is cooled, so that the device can use the gaseous refrigeration medium to exchange heat with the recovery bottle 31 to reduce the temperature of the recovery bottle 31.

[0045] In this embodiment, the gaseous refrigeration medium can be helium.

[0046] Please refer to Figures 1 to 4 , the phosphine mixed gas purification and recovery system further includes a recovery pipeline 28. Both ends of the recovery pipeline 28 are respectively communicated with the discharge pipe 13 and the recovery bottle 31. A recovery pneumatic diaphragm valve 281 and a recovery manual diaphragm valve 282 are sequentially arranged on the recovery pipeline 28 along the intake direction.

[0047] Please refer toFigures 1 to 4 The phosphine gas mixture purification and recovery system further includes a pressure measurement pipeline 29. One end of the pressure measurement pipeline 29 is communicated with the detection pipeline 27, and the other end is communicated with the pipeline between the recovery pneumatic diaphragm valve 281 and the recovery manual diaphragm valve 282. A pressure measurement pneumatic diaphragm valve 291 and a third pressure transmitter 292 are provided on the pressure measurement pipeline 29. By setting the pressure measurement pipeline 29, the gas pressure on the recovery pipeline 28 can be detected in real time, thereby improving the controllability before the gas reaches the recovery bottle 31.

[0048] The present invention also relates to a method for purifying and recovering a phosphine gas mixture. The technical solution is as follows: Using the phosphine gas mixture purification and recovery system to purify and recover the phosphine gas mixture, including the following steps: Step 1: Place the recovery bottle 31 in the recovery cold tank 3 and connect it to the recovery pipeline 28, and pre-cool the gas-liquid separation cold trap 1 to -50°C. Step 2: Use the replacement pipeline 23 to introduce the helium gas inside the helium gas cylinder into the gas-liquid separation cold trap 1 to squeeze out the air in the gas-liquid separation cold trap 1. Step 3: Use the vacuum pipeline 24 to extract the helium gas in the gas-liquid separation cold trap 1 until the gas-liquid separation cold trap 1 is in a vacuum state. Step 4: Use the feed pipeline 21 to reduce the pressure of the phosphine gas mixture in the torpedo vehicle to 0.5 Mpa and introduce it into the gas-liquid separation cold trap 1. At the same time, cool the gas-liquid separation cold trap 1 to -90°C, and open the exhaust pipeline 22. The phosphine liquefies, and the non-condensable gas is discharged from the gas-liquid separation cold trap 1 along the exhaust pipeline 22 to obtain liquid phosphine. Step 5: Cool the gas-liquid separation cold trap 1 to -100°C and continuously input the phosphine gas mixture to make the pressure in the gas-liquid separation cold trap 1 0.5 bar higher than one atmospheric pressure until the liquid phosphine recovery is completed. Step 6: Close the feed pipeline 21 and the exhaust pipeline 22. The gas-liquid separation cold trap 1 stops cooling and stands still until room temperature. The liquid phosphine vaporizes as the temperature rises, and the pressure inside the gas-liquid separation cold trap 1 rises to obtain purified phosphine. Step 7: Use the recovery cold tank 3 to pre-cool the recovery bottle 31 to -50°C, and use the recovery pipeline 28 to introduce the purified phosphine into the recovery bottle 31 for internal storage and recovery. Step 8: Calculate the purified phosphine inside the recovery bottle 31 through the weighing base 35. After reaching the specified weight, close the recovery cold tank 3 and remove the recovery bottle 31.

[0049] The above are all the preferred embodiments of this application, and the protection scope of this application is not limited accordingly. Therefore, all equivalent changes made according to the structure, shape, and principle of this application should be covered within the protection scope of this application.

Claims

1. A phosphine mixed gas purification and recovery system, characterized in that: include: A control pipeline assembly (2), one end of which is connected to the torpedo vehicle; A gas-liquid separation cold trap (1), wherein a feed pipe (11) and a discharge pipe (13) are connected to the gas-liquid separation cold trap (1), wherein the feed pipe (11) is connected to the other end of the control pipeline assembly (2) to receive the phosphine mixed gas in the torpedo vehicle, and the gas-liquid separation cold trap (1) is used to refrigerate the received phosphine mixed gas in the torpedo vehicle to obtain liquid phosphine and non-condensable gas; A recovery cold tank (3), wherein a recovery bottle (31) connected to a discharge pipe (13) is provided in the recovery cold tank (3) for recovering and storing gaseous phosphine obtained by treatment in a gas-liquid separation cold trap (1), wherein a spiral first heat exchange channel (32) is provided on the outside of the recovery bottle (31) along its length direction, and a spiral second heat exchange channel (33) is provided on the inner wall of the recovery cold tank (3) along its height direction, wherein the second heat exchange channel (33) has the same spiral direction as the first heat exchange channel (32), and the first heat exchange channel (32) and the second heat exchange channel (33) are butt-jointed to form a refrigeration channel (34), wherein a gaseous refrigeration medium is provided inside the refrigeration channel (34).

2. A phosphine mixed gas purification and recovery system according to claim 1, characterized in that: The control pipeline assembly (2) comprises: A feed pipeline (21), one end of which is connected to the torpedo vehicle, and the other end of which is connected to the feed pipe (11); An exhaust pipeline (22), wherein the gas-liquid separation cold trap (1) is provided with an exhaust pipe (12) connected to the gas-liquid separation cold trap (1), one end of the exhaust pipeline (22) is connected to the exhaust pipe (12), and the other end is connected to the exhaust gas treatment device; A replacement pipeline (23), wherein a replacement manual diaphragm valve (231), a replacement check valve (232), a replacement pressure reducing valve with a pressure gauge (233) and a replacement pneumatic diaphragm valve (234) are sequentially arranged on the replacement pipeline (23) along the air inlet direction; one end of the replacement pipeline (23) is connected to the feed pipe (11) through a detection pipeline (27), and the other end is connected to a helium bottle; the replacement pipeline (23) can be used to pass helium into the gas-liquid separation cold trap (1) to discharge air in the gas-liquid separation cold trap (1); A vacuum pipeline (24), wherein a vacuum pneumatic diaphragm valve (241), a vacuum pressure gauge (242) and a vacuum manual diaphragm valve (243) are sequentially arranged on the vacuum pipeline (24) along the gas outlet direction; one end of the vacuum pipeline (24) is connected to the feed pipe (11) via a detection pipeline (27); the other end is provided with a vacuum pump and is connected to the tail gas treatment device; the vacuum pipeline (24) is used to extract helium from the gas-liquid separation cold trap (1); An exhaust pipeline (25), wherein the exhaust pipeline (25) is provided with an exhaust pneumatic diaphragm valve (251), an exhaust check valve (252) and an exhaust manual diaphragm valve (253) in sequence along the gas outlet direction; one end of the exhaust pipeline (25) is connected to the feed pipe (11) through a detection pipeline (27) for exhausting the remaining gas inside the control pipeline assembly (2).

3. A phosphine mixed gas purification and recovery system according to claim 2, characterized in that: The feed pipeline (21) is provided with a plurality of feed pressure reducing valves (211), and the plurality of feed pressure reducing valves (211) are arranged on the feed pipeline (21) at intervals in sequence along the gas inlet direction. A feed pressure gauge (212) corresponding to the feed pressure reducing valve (211) is provided on one side of the outlet of each feed pressure reducing valve (211). The plurality of feed pressure gauges (212) are arranged on the feed pipeline (21) and are used to detect the gas pressure after being decompressed by the corresponding feed pressure reducing valve (211). A feed check valve (213) is provided on one end of the feed pipeline (21) close to the gas-liquid separation cold trap (1).

4. A phosphine mixed gas purification and recovery system according to claim 3, characterized in that: An exhaust pneumatic diaphragm valve (221), an exhaust pressure reducing valve with a pressure gauge (222) and an exhaust manual diaphragm valve (223) are sequentially arranged on the exhaust pipeline (22) along the exhaust direction; one end of the exhaust pipeline (22) is connected to the exhaust pipe (12), and the other end is connected to the exhaust gas treatment device; a pressure relief bypass (26) is also arranged on one side of the exhaust pipeline (22).

5. A phosphine mixed gas purification and recovery system according to claim 3, characterized in that: A pressure relief manual diaphragm valve (261) and a pressure relief proportional unloading valve (262) are sequentially arranged on the pressure relief bypass (26) along the gas outlet direction; one end of the pressure relief bypass (26) is connected to the pipeline between the exhaust pipeline (22) and the gas outlet pipe (12), and the other end is connected to the exhaust gas treatment device; a first pressure detection component (263) is also arranged on the gas inlet end of the pressure relief bypass (26) for real-time detection of the gas pressure on the pressure relief bypass (26).

6. A phosphine mixed gas purification and recovery system according to claim 5, characterized in that: The detection pipeline (27) is provided with two detection pneumatic diaphragm valves (271) arranged at intervals, a second pressure detection component (272) and a vacuum gauge component (273); the second pressure detection component (272) is located between the two detection pneumatic diaphragm valves (271) and is used to monitor and measure the gas pressure on the detection pipeline (27); the vacuum gauge component (273) is located at one end of the detection pipeline (27) close to the exhaust pipeline (25); a feed pneumatic diaphragm valve (111) is provided on the feed pipe (11); one end of the detection pipeline (27) is connected to the feed pipe (11), and the other end is respectively connected to the displacement pipeline (23), the vacuum pipeline (24) and the exhaust pipeline (22).

7. A phosphine mixed gas purification and recovery system according to claim 1, characterized in that: The recycling cold tank (3) further comprises: a weighing base (35), and the recycling cold tank (3) is mounted on one side of the upper end of the weighing base (35); A refrigeration container (36) containing a gaseous refrigerant medium is provided therein, the refrigeration container (36) is mounted on the other side of the upper end of the weighing base (35), a plurality of refrigeration fins are provided on the refrigeration container (36), and the inlet and outlet of the refrigeration container (36) are respectively connected to the two ends of the second heat exchange channel (33); an air pump (37), the air pump (37) is mounted on the weighing base (35) and is located on one side of the refrigeration container (36), and is used to drive the gaseous refrigerant medium to circulate inside the recovery cold tank (3).

8. A phosphine mixed gas purification and recovery system according to claim 6, characterized in that: The phosphine mixed gas purification and recovery system further comprises a recovery pipeline (28), the two ends of which are respectively connected to a discharge pipe (13) and a recovery bottle (31), and a recovery pneumatic diaphragm valve (281) and a recovery manual diaphragm valve (282) are sequentially arranged on the recovery pipeline (28) along an air inlet direction.

9. A phosphine mixed gas purification and recovery system according to claim 8, characterized in that: The phosphine mixed gas purification and recovery system further comprises a pressure measuring pipeline (29), one end of the pressure measuring pipeline (29) is connected to the detection pipeline (27), and the other end is connected to the pipeline between the recovery pneumatic diaphragm valve (281) and the recovery manual diaphragm valve (282), and the pressure measuring pipeline (29) is provided with a pressure measuring pneumatic diaphragm valve (291) and a third pressure transmitter (292).

10. A method for purifying and recovering phosphine mixed gas, characterized in that: The phosphine mixed gas purification and recovery system as claimed in claims 1 to 9 is used to purify and recover the phosphine mixed gas, comprising the following steps: Step 1: placing the recovery bottle (31) in the recovery cold tank (3) and connecting it to the recovery pipeline (28), and precooling the gas-liquid separation cold trap (1) to -50°C; Step 2: using the displacement pipeline (23) to pass the helium in the helium bottle into the gas-liquid separation cold trap (1), thereby squeezing out the air in the gas-liquid separation cold trap (1); Step 3: Using the vacuum pipeline (24) to extract the helium in the gas-liquid separation cold trap (1) until the gas-liquid separation cold trap (1) is vacuumed; Step 4: using the feed pipeline (21) to reduce the pressure of the phosphine mixed gas in the torpedo car to 0.5 MPa, and passing it into the gas-liquid separation cold trap (1), while the gas-liquid separation cold trap (1) is cooled to -90°C, and the exhaust pipeline (22) is opened, the phosphine is liquefied, and the non-condensable gas is discharged from the gas-liquid separation cold trap (1) along the exhaust pipeline (22), thereby obtaining liquid phosphine; Step 5: The gas-liquid separation cold trap (1) is cooled to -100°C, and the phosphine mixed gas is continuously inputted so that the pressure of the gas-liquid separation cold trap (1) is higher than the atmospheric pressure by 0.5 bar until the liquid phosphine is completely recovered; Step 6: closing the feed pipeline (21) and the exhaust pipeline (22), stopping the refrigeration of the gas-liquid separation cold trap (1) and allowing it to stand at room temperature, the liquid phosphine gasifies as the temperature rises, the pressure inside the gas-liquid separation cold trap (1) rises, and purified phosphine is obtained; Step 7: precooling the recovery bottle (31) to -50°C using the recovery cold tank (3), and introducing the purified phosphine into the recovery bottle (31) for storage and recovery using the recovery pipeline (28); Step 8: Calculate the purified phosphine inside the recovery bottle (31) by weighing the base (35). When the specified weight is reached, close the recovery cold tank (3) and remove the recovery bottle (31).

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