An ethylene oxide tail gas treatment system

Abstract

The application relates to an ethylene oxide tail gas treatment system and relates to the technical field of tail gas treatment. The ethylene oxide tail gas treatment system comprises a cooling assembly, a collecting assembly and a treatment mechanism. The treatment mechanism comprises an absorption tower, an ethylene glycol waste liquid tank, a burner and a liquid spraying assembly. The application carries out cooling treatment on the tail gas discharged from an EO sterilization cabinet through the cooling assembly, so that most of the ethylene oxide in the tail gas is liquefied. The collecting assembly collects the liquefied ethylene oxide. The absorption tower processes the gas discharged from the cooling assembly and the collecting assembly, so that the ethylene oxide in the gas is converted into ethylene glycol solution and collected through the ethylene glycol waste liquid tank. The gas discharged from the absorption tower is combusted through the burner. The liquid spraying assembly sprays the generated ethylene glycol solution into the burner and ensures continuous combustion of the burner, so that the ethylene oxide recovery cost is reduced, and the influence of the ethylene oxide tail gas on the external environment is reduced.

Description

Technical Field

[0001] This application relates to the technical field of exhaust gas treatment, and in particular to an ethylene oxide exhaust gas treatment system. Background Technology

[0002] Ethylene oxide (EO) is a broad-spectrum sterilizing agent that can kill various microorganisms at room temperature, including spores, tubercle bacilli, bacteria, viruses, and fungi. It has the following advantages: it can kill all microorganisms, including bacterial spores; sterilized items can be wrapped and completely sealed, maintaining a sterile state before use; relatively speaking, EO does not corrode plastics, metals, or rubber, and will not cause items to yellow or become brittle; it can penetrate and sterilize irregularly shaped items; and it can be used to sterilize items that cannot be sterilized by immersion in disinfectants, dry heat, pressure, steam, or other chemical gases. Due to these advantages, EO sterilization equipment is a key piece of equipment for manufacturers of disposable sterile medical devices.

[0003] Chinese patent CN107648999B discloses a process and device for treating ethylene oxide waste gas through disinfection and sterilization. The process involves passing the ethylene oxide waste gas into a multi-stage absorption spray tower, where it sequentially passes through a solid acid catalyst layer and a packing layer. Under the action of water spray, some of the ethylene oxide in the waste gas dissolves in the water and flows with the water into the solid acid catalyst layer. Under the action of the solid acid catalyst, the ethylene oxide reacts with the water to form ethylene glycol. A small amount of ethylene oxide that has not reacted with the water enters a collection tank with the water. In the collection tank, it passes through multiple staggered baffles and again comes into contact with the solid acid catalyst in the baffles to undergo a hydration reaction. After multi-stage absorption, the EO content can basically meet the emission standards, and there is no waste liquid discharge during the process. The technology is simple to operate, has low overall operating costs, and is highly safe.

[0004] The main method involves passing ethylene oxide into acidic water, where it reacts with water to produce ethylene glycol. The ethylene glycol is then concentrated and stored, and subsequently dehydrated to regenerate ethylene oxide, thus achieving ethylene oxide recovery and reducing its content in the tail gas, ultimately ensuring safe emission. However, to achieve ethylene oxide recovery, the collected ethylene glycol solution also needs to be purified and then undergo a series of chemical reactions to regenerate ethylene oxide, which increases the cost of ethylene oxide recovery.

[0005] Therefore, there is an urgent need to establish an ethylene oxide tail gas treatment system that can reduce the cost of ethylene oxide recovery and reduce the impact of ethylene oxide tail gas on the external environment. Summary of the Invention

[0006] To facilitate the reduction of ethylene oxide recovery costs and the reduction of the impact of ethylene oxide tail gas on the external environment, this application provides an ethylene oxide tail gas treatment system.

[0007] This application provides an ethylene oxide tail gas treatment system, which adopts the following technical solution: An ethylene oxide tail gas treatment system includes a cooling component, a collection component, and a treatment mechanism. The cooling component is used to cool the tail gas discharged from an EO sterilizer and liquefy the ethylene oxide. The collection component is used to collect and store the liquefied ethylene oxide. The treatment mechanism is used to treat the gas discharged from the cooling component and the collection component. The treatment mechanism includes: An absorption tower, wherein the absorption tower is provided in multiple stages, the multiple stages of the absorption tower being used to convert ethylene oxide in the gas discharged from the cooling component and the collection component into ethylene glycol layer by layer; An ethylene glycol waste tank is used to store the ethylene glycol solution discharged from the absorption tower. A burner for combusting the gas discharged from the absorption tower; The liquid spraying assembly is used to spray the solution in the ethylene glycol waste tank into the burner for auxiliary combustion.

[0008] By adopting the above technical solution, the cooling component cools the exhaust gas from the EO sterilizer, thereby liquefying most of the ethylene oxide in the exhaust gas. The collection component collects the liquefied ethylene oxide. At the same time, the absorption tower treats the gas discharged from the cooling and collection components, thereby converting the ethylene oxide in the gas into an ethylene glycol solution, which is then collected in an ethylene glycol waste tank. The gas discharged from the absorption tower is then burned in a burner. The spraying component sprays the generated ethylene glycol solution into the burner and ensures continuous combustion, which helps to reduce the cost of ethylene oxide recovery and reduce the impact of ethylene oxide exhaust gas on the external environment.

[0009] Furthermore, the liquid spraying assembly includes: A waste liquid concentrator is connected to an ethylene glycol waste liquid tank via a drain pipe and is used to concentrate the discharged ethylene glycol waste liquid. The heat generated by the burner is used to assist the waste liquid concentrator in heating the ethylene glycol waste liquid. A drain pump, which is installed on a drain pipe and is used to pump the solution in the ethylene glycol waste tank into a waste concentration tank; A combustion injection pump is connected to a waste liquid concentrator and is used to spray the solution in the waste liquid concentrator into the burner for combustion.

[0010] By adopting the above technical solution, the drain pump pumps the ethylene glycol solution in the ethylene glycol waste tank into the waste concentration tank through the drain pipe. The heat generated by the burner combustion helps to concentrate the discharged ethylene glycol solution. Finally, the concentrated ethylene glycol solution is sprayed into the burner for combustion treatment, thereby utilizing the generated ethylene glycol solution as waste and ensuring that the burner continuously combusts the gas discharged from the absorption tower.

[0011] Furthermore, the absorption tower is a combined bubbling reaction tank, and a concentration detector for detecting the concentration of ethylene glycol is installed inside the absorption tower. The ethylene glycol waste liquid generated in the combined bubbling reaction tank is discharged into the ethylene glycol waste liquid tank by a drainage pump, and the drainage pump is electrically connected to the concentration detector.

[0012] By adopting the above technical solution, an acidic aqueous solution is set in the combined bubbling reaction tank. The acidic aqueous solution reacts with ethylene oxide in the gas to finally produce ethylene glycol. When the concentration detector detects that the concentration of ethylene glycol solution in the combined bubbling reaction tank has reached the set value, the drainage pump discharges the ethylene glycol solution in the combined bubbling reaction tank into the ethylene glycol waste tank, thereby ensuring the absorption effect of the combined bubbling reaction tank on ethylene oxide in the gas.

[0013] Furthermore, the EO sterilizer discharges exhaust gas through an exhaust pipe, which is equipped with a pressurization component for protecting and pressurizing the interior of the exhaust pipe. The pressurization component includes: An inert gas storage tank, wherein the inert gas storage tank is connected to an exhaust pipe via an inlet pipe and is used to supply inert gas into the exhaust pipe; A first pneumatic ball valve is installed on the air inlet pipe and is used to open or close the air inlet pipe. The first booster is installed on the exhaust pipe and is used to boost the gas inside the exhaust pipe before it is discharged.

[0014] By adopting the above technical solution, when the exhaust gas volume in the exhaust pipe is large, the first pneumatic ball valve automatically opens the intake pipe, thereby discharging the inert gas in the inert gas storage tank into the exhaust pipe, thereby increasing the gas pressure in the exhaust pipe and reducing the proportion of ethylene oxide in the exhaust pipe. At the same time, the first booster pressurizes the gas in the exhaust pipe, thereby protecting and pressurizing the inside of the exhaust pipe, which facilitates the subsequent treatment of the exhaust gas.

[0015] Furthermore, the cooling assembly includes: A cooling tower, which is internally connected to an exhaust pipe and is used to cool the pressurized gas and liquefy ethylene oxide; A chiller, which is connected to a cooling tower and is used to provide a low-temperature environment for the cooling tower; The first pipe is installed on the cooling tower and is used to discharge the cooled gas into the absorption tower. A discharge pipe is installed on the cooling tower and is used to discharge the liquefied liquid into the collection assembly.

[0016] By adopting the above technical solution, when the exhaust gas enters the cooling tower, the refrigeration unit provides a low-temperature environment for the cooling tower, thereby liquefying the ethylene oxide in the exhaust gas. Then, the unliquefied gas is discharged into the absorption tower for treatment through the first pipe, and the liquefied liquid is discharged into the collection component for collection through the discharge pipe, thereby facilitating the recycling of ethylene oxide.

[0017] Furthermore, the collection component includes: An EO storage tank, which is connected to a discharge pipe and is used to store the liquid discharged from the discharge pipe; An electronic scale, used for weighing EO storage tanks; A vent pipe is installed at the top of the EO storage tank and communicates with the inside of the first pipe. The vent pipe is used to discharge the gas in the EO storage tank into the first pipe. The second pneumatic ball valve is installed on the vent pipe. The second pneumatic ball valve is used to control the opening or closing of the vent pipe and prevent the gas in the first pipe from entering the EO storage tank.

[0018] By adopting the above technical solution, the EO storage tank is used to store the liquid discharged from the discharge pipe. When the electronic scale detects that the weight of the EO storage tank and its internal liquid reaches the set value, the liquid in the EO storage tank is transferred to the storage tank for storage, so that the ethylene oxide can be discharged back into the EO sterilizer for use later. When the amount of gas in the vent pipe increases, the second pneumatic ball valve opens, and the vent pipe discharges the gas in the EO storage tank into the first pipe, thereby reducing the gas pressure value in the EO storage tank and improving the safety of the EO storage tank.

[0019] Furthermore, the first pipe is provided with a buffer assembly for buffering the discharged gas, the buffer assembly comprising: A flow buffer tank, which is connected to a first pipe and a vent pipe and is used to buffer the gas discharged from the first pipe and the vent pipe; The third pipe is installed on the flow buffer tank and is connected to the inside of the absorption tower; A one-way valve is installed on the third pipe and allows gas from the flow buffer tank to enter the absorption tower only from the third pipe. The second flow control valve is installed on the third pipe and located between the check valve and the absorption tower. The second flow control valve is used to control the flow in the third pipe. A booster pipe is installed on the flow buffer tank and is connected to the inside of a third pipe between the second flow control valve and the absorption tower. The third pneumatic ball valve is installed on the booster pipe. When the amount of gas in the flow buffer tank is greater than the set value, the third pneumatic ball valve is opened and the booster pipe is closed. The second booster is installed on the booster pipe and is used to boost the gas passing through the third pneumatic ball valve.

[0020] By adopting the above technical solution, when the amount of gas in the flow buffer tank is large, the third pneumatic ball valve opens and the booster pipe closes. Under the control of the second flow control valve, the amount of gas discharged into the absorption tower through the third pipe is relatively stable. When the amount of gas in the flow buffer tank is small, the third pneumatic ball valve closes and the booster pipe opens. The second booster pressurizes the gas in the booster pipe, and finally the gas in the booster pipe and the third pipe are discharged into the absorption tower together, thereby ensuring the stability of the gas entering the absorption tower.

[0021] Furthermore, the exhaust pipe is equipped with a non-thermal regenerative dryer for removing water from the pressurized exhaust gas, and the inert gas storage tank is connected to the non-thermal regenerative dryer and assists the non-thermal regenerative dryer in desorption.

[0022] By adopting the above technical solution, the heatless regenerative dryer removes water from the pressurized exhaust gas, thereby reducing the moisture content in the exhaust gas and reducing the probability of the moisture in the exhaust gas condensing at low temperature in the cooling tower and clogging the cooling tower. At the same time, the inert gas in the inert gas storage tank assists in the desorption of the heatless regenerative dryer, improving the desorption effect of the heatless regenerative dryer.

[0023] Furthermore, the drain end of the heatless regeneration dryer is connected to the absorption tower through a drain pipe. The desorbed material from the heatless regeneration dryer is discharged into the absorption tower through the drain pipe. A negative pressure pump is installed on the drain pipe to reduce the air pressure at the drain end of the heatless regeneration dryer.

[0024] By adopting the above technical solution, the desorbed gas-liquid mixture contains ethylene oxide. The desorbed substance is discharged into the absorption tower through the drain pipe for absorption treatment. At the same time, the gas pressure at the drain end of the heatless regeneration dryer is reduced by the negative pressure pump, which facilitates the desorption treatment of moisture in the heatless regeneration dryer.

[0025] Furthermore, the exhaust end of the first booster is provided with a rapid processing component for handling exhaust gas volumes that are less than a set value. The rapid processing component includes: A pneumatic three-way ball valve is installed on the exhaust end of the first booster. The first outlet of the pneumatic three-way ball valve is connected to the inside of the cooling tower. When the exhaust gas volume in the exhaust pipe is greater than a set value, the pneumatic three-way ball valve is activated, and the exhaust pipe is connected to the inside of the cooling tower. The quick-connect pipe is connected to the second outlet of the pneumatic three-way ball valve, and the end of the quick-connect pipe away from the pneumatic three-way ball valve is connected to the inside of the flow buffer tank.

[0026] By adopting the above technical solution, when the exhaust gas volume in the exhaust pipe is greater than the set value, the pneumatic three-way ball valve opens, allowing the gas in the exhaust pipe to enter the cooling tower. When the exhaust gas volume in the exhaust pipe is less than the set value, the three-way ball valve closes, allowing the gas in the exhaust pipe to enter the fast pipe and be discharged into the flow buffer tank. Ultimately, when the exhaust gas volume in the exhaust pipe is low, it does not enter the cooling tower, thereby reducing the energy loss in the cooling tower.

[0027] In summary, this application includes at least one of the following beneficial technical effects: 1. Inert gas is introduced into the exhaust gas from the EO sterilizer for protection and pressurization. The pressurized exhaust gas is then cooled in a cooling tower to liquefy the ethylene oxide in the exhaust gas. The liquefied ethylene oxide is then stored in an EO storage tank. Simultaneously, the gas cooled by the cooling tower is absorbed in an absorption tower, converting a small amount of ethylene oxide in the gas into an ethylene glycol solution. Finally, the exhaust gas is burned in a burner, and the converted ethylene glycol is used to assist combustion in the burner. This reduces the cost of ethylene oxide recovery and minimizes the environmental impact of ethylene oxide exhaust gas.

[0028] 2. The gas entering the cooling tower is dried by a heatless regenerative dryer to reduce the moisture content of the gas entering the cooling tower. At the same time, the desorbed moisture and gas are discharged into the absorption tower to absorb the ethylene oxide, thereby improving the service life of the cooling tower. Attached Figure Description

[0029] Figure 1 This is a schematic diagram of the structure of Embodiment 1 of this application; Figure 2 yes Figure 1 Enlarged diagram of section A in the middle; Figure 3 yes Figure 1 Enlarged diagram of section B; Figure 4 This is a schematic diagram of the structure of Embodiment 2 of this application; Figure 5 yes Figure 4 Enlarged diagram of section C.

[0030] Reference numerals: 1. EO sterilizer; 11. Vacuum valve; 12. Dry vacuum pump; 13. Exhaust pipe; 2. Pressurization assembly; 21. Inlet pipe; 22. First pneumatic ball valve; 23. First booster; 3. Cooling assembly; 31. Cooling tower; 32. Refrigeration unit; 33. First pipe; 331. Demister; 332. First flow control valve; 34. Discharge pipe; 341. Fourth pneumatic ball valve; 4. Collection assembly; 41. EO storage tank; 411. Second pipe; 42. Electronic scale; 43. Vent pipe; 44. Second pneumatic ball valve; 5. Buffer assembly; 51. Flow buffer tank; 511. 52. Safety pipe; 53. Third pipe; 54. Check valve; 55. Second flow control valve; 56. Booster pipe; 57. Third pneumatic ball valve; 68. Second booster; 69. Processing mechanism; 60. Absorption tower; 611. Drain pump; 62. Ethylene glycol waste liquid tank; 63. Burner; 631. Combustion fan; 64. Injection assembly; 641. Waste liquid concentrator; 642. Drain pump; 643. Combustion injection pump; 70. Rapid processing component; 71. Pneumatic three-way ball valve; 72. Rapid pipe; 81. Heatless regeneration dryer; 82. Regeneration pipe; 83. Heater; 84. Drain pipe; 85. Negative pressure pump. Detailed Implementation

[0031] The following is in conjunction with the appendix Figure 1-5 This application will be described in further detail.

[0032] This application discloses an ethylene oxide tail gas treatment system.

[0033] Example 1 Reference Figure 1 An ethylene oxide tail gas treatment system includes a cooling component 3, a collection component 4, and a treatment mechanism 6. The cooling component 3 is used to cool the tail gas discharged from the EO sterilizer 1 and liquefy the ethylene oxide. The collection component 4 is used to collect and store the liquefied ethylene oxide. The treatment mechanism 6 is used to treat the gas discharged from the cooling component 3 and the collection component 4.

[0034] Reference Figure 1 and Figure 2The exhaust gas discharged from the EO sterilizer 1 is pre-treated by a vacuum valve 11 and a dry vacuum pump 12, and then discharged through an exhaust pipe 13. The exhaust pipe 13 is equipped with a pressurization assembly 2 for protecting and pressurizing the interior of the exhaust pipe 13. The pressurization assembly 2 includes an inert gas storage tank, a first pneumatic ball valve 22, and a first booster 23. The inert gas storage tank is connected to the interior of the exhaust pipe 13 through an inlet pipe 21, and is used to supply gas to the interior of the exhaust pipe 13. Inert gas; a first pneumatic ball valve 22 is fixedly installed on the exhaust pipe 13. When the exhaust gas volume in the exhaust pipe 13 is large, the first pneumatic ball valve 22 is opened, allowing the inert gas in the inert gas storage tank to enter the exhaust pipe 13 through the inlet pipe 21, thereby reducing the percentage of ethylene oxide in the exhaust pipe 13 and reducing the probability of ethylene oxide explosion in the exhaust pipe 13; when the exhaust gas volume in the exhaust pipe 13 is small, the first pneumatic ball valve 22 is closed; the inert gas in this embodiment can be nitrogen or carbon dioxide.

[0035] Reference Figure 1 and Figure 2 In order to facilitate the control of the amount of inert gas entering the exhaust pipe 13 according to the gas content in the exhaust pipe 13, a speed regulating valve is also fixedly installed on the intake pipe 21. The speed regulating valve makes the amount of inert gas entering the exhaust pipe 13 change in a certain proportion with the amount of exhaust gas in the exhaust pipe 13. The first booster 23 is fixedly installed on the exhaust pipe 13. The first booster 23 is used to boost the gas in the exhaust pipe 13 before it is discharged.

[0036] Reference Figure 1 and Figure 2 The cooling assembly 3 is used to cool the pressurized exhaust gas, thereby liquefying the ethylene oxide in the exhaust gas. The cooling assembly 3 includes a cooling tower 31, a chiller 32, a first pipe 33, and a discharge pipe 34. The cooling tower 31 is fixedly connected to the end of the exhaust pipe 13 away from the EO sterilizer 1. The cooling tower 31 is used to cool the pressurized gas, thereby liquefying the ethylene oxide in the gas. The chiller 32 is connected to the cooling tower 31 and is used to provide a low-temperature environment for the cooling tower 31, so that the cooling tower 31 can continuously liquefy the ethylene oxide in the gas. The first pipe 33 is set at the bottom of the cooling tower 31 and is used to discharge the cooled gas into the processing mechanism 6 for subsequent processing. The discharge pipe 34 is set at the bottom of the cooling tower 31 and is used to discharge the cooled liquid into the collection assembly 4. In this embodiment, a second temperature sensor is installed inside the cooling tower 31.

[0037] Reference Figure 1 and Figure 2Since the discharge pipe 34 is internally connected to the first pipe 33, the liquid and gas discharged from the cooling tower 31 are discharged separately. The installation height of the discharge pipe 34 is lower than that of the first pipe 33, so that the liquid enters the discharge pipe 34 under the action of gravity. In order to reduce the possibility of a large amount of gas entering the discharge pipe 34, a fourth pneumatic ball valve 341 is installed on the discharge pipe 34. When a large amount of gas enters the discharge pipe 34, the fourth pneumatic ball valve 341 closes the discharge pipe 34, thereby reducing the probability of gas entering the discharge pipe 34. When the gas content in the discharge pipe 34 is low, the fourth pneumatic ball valve 341 opens the discharge pipe 34, allowing the liquid to be discharged through the discharge pipe 34, ultimately reducing the probability of gas entering the collection component 4 through the discharge pipe 34.

[0038] Reference Figure 1 and Figure 2 A first temperature sensor and a first pressure sensor for detecting gas temperature and pressure are fixedly installed on the first tube 33. Since the gas in the first tube 33 contains a large amount of mist-like ethylene oxide, a demister 331 is also fixedly installed on the first tube 33. The demister 331 blocks the mist-like ethylene oxide in the first tube 33 and causes the mist-like ethylene oxide to re-condense into liquid, which then flows back into the discharge pipe 34 through the first tube 33. A first flow control valve 332 is also fixedly installed on the first tube 33. The first flow control valve 332 automatically adjusts the flow rate of the gas discharged from the first tube 33 to improve the flow rate stability of the gas discharged from the first tube 33.

[0039] Reference Figure 1 and Figure 2 The collection component 4 is used to collect and store liquefied ethylene oxide. The collection component 4 includes an EO storage tank 41, an electronic scale 42, a vent pipe 43, and a second pneumatic ball valve 44. The EO storage tank 41 is internally connected to the side of the discharge pipe 34 away from the cooling tower 31. The EO storage tank 41 is used to store the liquid discharged from the discharge pipe 34. The electronic scale 42 is used to weigh the EO storage tank 41. When the electronic scale 42 shows that the weight of the EO storage tank 41 reaches the set value, the liquid ethylene oxide stored in the EO storage tank 41 is discharged into a storage tank for storing ethylene oxide, so that the ethylene oxide can be discharged back into the EO sterilizer 1 for use later. The vent pipe 43 is fixedly installed on the top of the EO storage tank 41. The vent pipe 43 is used to discharge excess gas in the EO storage tank 41 into the first pipe 33, thereby reducing the gas content in the EO storage tank 41. In this embodiment, the electronic scale 42 adopts a suspended structure.

[0040] Reference Figure 1 and Figure 2The second pneumatic ball valve 44 is fixedly installed on the vent pipe 43. The second pneumatic ball valve 44 is used to control the opening or closing of the vent pipe 43, thereby preventing the gas in the first pipe 33 from entering the EO storage tank 41. Specifically, when the gas content in the EO storage tank 41 is large, the second pneumatic ball valve 44 automatically opens, thereby allowing the gas in the EO storage tank 41 to enter the first pipe 33. When the gas content in the EO storage tank 41 is small and the gas content in the first pipe 33 is large, the second pneumatic ball valve 44 automatically closes, thereby preventing the gas in the first pipe 33 from entering the EO storage tank 41. At the same time, a second pressure sensor and a manual valve are also fixedly installed on the vent pipe 43. The second pressure sensor is used to monitor the gas pressure value in the vent pipe 43 in real time, and the manual valve is used to manually open or close the vent pipe 43.

[0041] Reference Figure 1 and Figure 2 The bottom of the EO storage tank 41 is provided with a second pipe 411 that communicates with the inside of the processing mechanism 6. A fifth pneumatic ball valve is provided on the second pipe 411. The fifth pneumatic ball valve is used to control the opening or closing of the second pipe 411. When the gas pressure at the bottom of the EO storage tank 41 is high, the fifth pneumatic ball valve is opened by gas, thereby opening the second pipe 411, so that the gas inside the EO storage tank 41 can be directly discharged into the second pipe 411.

[0042] Reference Figure 1 and Figure 2 A buffer assembly 5 is provided on the first pipe 33 to buffer the discharged gas, so that the gas discharged from the first pipe 33 can stably enter the processing mechanism 6. The buffer assembly 5 includes a flow buffer tank 51, a third pipe 52, a one-way valve 53, and a second flow control valve 54. The flow buffer tank 51 is connected to the first pipe 33 and the vent pipe 43, and is used to buffer the gas discharged from the first pipe 33 and the vent pipe 43. The third pipe 52 is fixedly installed on the flow buffer tank 51 and is located away from the flow buffer tank. One end of tank 51 is connected to the inside of absorption tower 61, thereby discharging the gas in flow buffer tank 51 into absorption tower 61; one-way valve 53 is fixedly installed on third pipe 52, and one-way valve 53 only allows the gas in third pipe 52 to enter absorption tower 61 from flow buffer tank 51; second flow control valve 54 is fixedly installed on third pipe 52, and the second flow control valve 54 is located between one-way valve 53 and absorption tower 61. The second flow control valve 54 is used to control the flow in third pipe 52, so that the flow discharged from third pipe 52 is relatively stable.

[0043] Reference Figure 1 and Figure 2The buffer assembly 5 also includes a booster pipe 55, a third pneumatic ball valve 56, and a second booster 57. One end of the booster pipe 55 is fixedly installed on the flow buffer tank 51 and communicates with the inside of the flow buffer tank 51. The other end of the booster pipe 55 is communicated with the inside of the third pipe 52. The connection point between the booster pipe 55 and the third pipe 52 is located between the second flow control valve 54 and the absorption tower 61. The third pneumatic ball valve 56 is fixedly installed on the booster pipe 55. When the amount of gas in the flow buffer tank 51 is greater than the set value, the third pneumatic ball valve 56 is opened, and the booster pipe 55 is closed. The second booster 57 is fixedly installed on the booster pipe 55. The second booster 57 is used to boost the gas that has passed through the third pneumatic ball valve 56.

[0044] Reference Figure 1 and Figure 2 Specifically, when the amount of gas in the flow buffer tank 51 is large, the third pneumatic ball valve 56 opens and the booster pipe 55 closes. Under the control of the second flow control valve 54, the amount of gas discharged into the absorption tower 61 through the third pipe 52 is relatively stable. When the amount of gas in the flow buffer tank 51 is small, the third pneumatic ball valve 56 closes and the booster pipe 55 opens. The second booster 57 pressurizes the gas in the booster pipe 55, and finally the gas in the booster pipe 55 and the third pipe 52 are discharged into the absorption tower 61 together, thereby ensuring the stability of the gas entering the absorption tower 61.

[0045] Reference Figure 1 and Figure 2 To improve the safety of the flow buffer tank 51, a safety pipe 511 is also fixedly installed on the flow buffer tank 51. The safety pipe 511 is used to connect the flow buffer tank 51 and the absorption tower 61. A safety pneumatic ball valve is installed on the safety pipe 511. When the amount of gas in the flow buffer tank 51 exceeds the safety value, the safety pneumatic ball valve opens, thereby quickly discharging the excess gas in the flow buffer tank 51 into the absorption tower 61.

[0046] Reference Figure 1 , Figure 2 and Figure 3The treatment unit 6 includes an absorption tower 61, an ethylene glycol waste liquid tank 62, and a burner 63. The absorption tower 61 has multiple stages, which are used to convert ethylene oxide in the gas discharged from the second pipe 411 and the flow buffer tank 51 into ethylene glycol layer by layer. The ethylene glycol waste liquid tank 62 is connected to the inside of the absorption tower 61 and is used to store the ethylene glycol solution discharged from the absorption tower 61. The burner 63 is connected to the inside of the absorption tower 61 and is used to combust the gas discharged from the absorption tower 61 to achieve the desired effect. To further reduce the ethylene oxide content in the final exhaust gas, the burner 63 is also equipped with a combustion fan 631 for continuously introducing air into the burner 63; the absorption tower 61 in this embodiment is a combined bubbling reaction tank, and an acidic aqueous solution is provided inside the absorption tower 61. The acidic aqueous solution reacts with the ethylene oxide in the gas to finally generate an ethylene glycol solution, while the unreacted gas is discharged from the top of the combined bubbling reaction tank, thereby absorbing the remaining ethylene oxide in the gas; the absorption tower 61 in this embodiment is provided in two sets.

[0047] Reference Figure 1 and Figure 3 The absorption tower 61 is also equipped with a concentration detector for detecting the concentration of ethylene glycol. The ethylene glycol solution generated in the combined bubbling reaction tank is discharged into the ethylene glycol waste tank 62 by the drainage pump 611. The concentration detector is electrically connected to the drainage pump 611. When the concentration detector detects that the concentration of ethylene glycol in the combined bubbling reaction tank reaches the set value, the drainage pump 611 is started to discharge the ethylene glycol solution in the absorption tower 61 into the ethylene glycol waste tank 62 for storage.

[0048] Reference Figure 1 and Figure 3The treatment unit 6 also includes a spraying assembly 64, which sprays the solution in the ethylene glycol waste tank 62 into the burner 63 for combustion. Because the combustible content in the exhaust gas from the absorption tower 61 is unstable, the spraying assembly 64 needs to continuously spray ethylene glycol solution into the burner 63 to ensure continuous combustion. The spraying assembly 64 includes a waste liquid concentrator 641, a drain pump 642, and a combustion spray pump 643. The waste liquid concentrator 641 is connected to the interior of the ethylene glycol waste tank 62 via a drain pipe. The liquid concentrator 641 is used to concentrate the ethylene glycol solution discharged from the drain pipe. The heat generated by the burner 63 is used to assist the waste liquid concentrator 641 in heating the ethylene glycol waste liquid. The drain pump 642 is fixedly installed on the drain pipe and is used to pump the ethylene glycol solution in the ethylene glycol waste liquid tank 62 into the waste liquid concentrator tank. The combustion injection pump 643 is connected to the inside of the waste liquid concentrator 641 and is used to pressurize the solution in the waste liquid concentrator 641 and spray it into the burner 63 through the nozzle for combustion, thereby ensuring the continuous and stable combustion of the burner 63.

[0049] Reference Figure 1 and Figure 2 Since the exhaust gas volume discharged from the EO sterilizer 1 is sometimes relatively small, in order to reduce the waste caused by the cooling component 3 cooling a small amount of exhaust gas, a quick processing component 7 is provided on the exhaust end of the first booster 23 for handling exhaust gas volumes that are less than a set value. The quick processing component 7 includes a pneumatic three-way ball valve 71 and a quick pipe 72. The pneumatic three-way ball valve 71 is fixedly installed on the exhaust pipe 13 on one side of the exhaust end of the first booster 23, and the first outlet of the pneumatic three-way pipe is connected to the interior of the cooling tower 31; the quick pipe 72 is connected to the second outlet of the pneumatic three-way ball valve 71, and the end of the quick pipe 72 away from the pneumatic three-way ball valve 71 is connected to the flow buffer tank 5. 1. Internal connection: When the amount of gas passing through the first booster 23 is less than the set value, the pneumatic three-way ball valve 71 is closed, and the exhaust pipe 13 is internally connected to the quick pipe 72, so that all the gas in the exhaust pipe 13 is discharged into the flow buffer tank 51 through the quick pipe 72, thereby reducing the energy loss of the cooling component 3; when the amount of gas passing through the first booster 23 is greater than the set value, the pneumatic three-way ball valve 71 is activated, and the exhaust pipe 13 is internally connected to the cooling tower 31, so that all the gas in the exhaust pipe 13 is passed into the cooling tower 31 for cooling, thereby facilitating the liquefaction and collection of ethylene oxide in the gas in the exhaust pipe 13.

[0050] The working principle of Embodiment 1 of this application is as follows: Inert gas is introduced into the exhaust gas discharged from the EO sterilizer 1 for protection and pressurization. The pressurized exhaust gas is then cooled by cooling tower 31, which liquefies the ethylene oxide in the exhaust gas. The liquefied ethylene oxide is then stored in EO storage tank 41. At the same time, the gas cooled by cooling tower 31 is absorbed by absorption tower 61, which converts a small amount of ethylene oxide in the gas into ethylene glycol solution. Finally, the exhaust gas is burned by burner 63. The converted ethylene glycol is used to assist combustion in burner 63, which helps to reduce the cost of ethylene oxide recovery and reduce the impact of ethylene oxide exhaust gas on the external environment.

[0051] Example 2 Reference Figure 4 and Figure 5 The difference between this embodiment and embodiment 1 is that, in order to improve the liquefaction effect of cooling tower 31 on ethylene oxide in the exhaust gas, the temperature value inside cooling tower 31 is relatively low. The moisture contained in the exhaust gas is easy to freeze in the low temperature environment, which will affect the normal discharge of liquefied ethylene oxide and exhaust gas. Therefore, a heatless regeneration dryer 8 for removing water from the pressurized exhaust gas is installed on exhaust pipe 13. The inert gas storage tank is connected to the heatless regeneration dryer 8 through regeneration pipe 81 and is used to assist the heatless regeneration dryer 8 in desorption.

[0052] Reference Figure 4 and Figure 5 The air inlet of the heatless regenerative dryer 8 is connected to the interior of the exhaust pipe 13. The heatless regenerative dryer 8 is located on the end of the pneumatic three-way ball valve 71 away from the first booster 23. Before the gas enters the cooling tower 31 through the pneumatic three-way ball valve 71, it is dried by the heatless regenerative dryer 8 to reduce the moisture content in the gas entering the cooling tower 31. The heatless regenerative dryer 8 in this embodiment is an adsorption dryer.

[0053] Reference Figure 4 and Figure 5The heatless regenerative dryer 8 includes an adsorption tank and a regeneration tank that are constantly alternating. When the gas pressurized by the first booster 23 enters the bottom of the adsorption tank of the heatless regenerative dryer 8 through the exhaust pipe 13, the adsorbent in the adsorption tank adsorbs the moisture in the gas, thereby reducing the moisture content in the gas discharged from the adsorption tank. At the same time, the switch control valve is opened, thereby opening the regeneration pipe 81, which facilitates the discharge of inert gas from the inert gas storage tank into the regeneration tank to regenerate the adsorbent. In order to improve the regeneration effect of the inert gas on the adsorbent, a heater 811 is provided on the regeneration pipe 81. The heater 811 is connected to the burner 63 and heats the inert gas in the heater 811 with the heat generated by the burner 63, thereby increasing the temperature of the inert gas entering the regeneration tank and improving the regeneration effect of the adsorbent in the regeneration tank. When the desorption in the regeneration tank is completed or the adsorbent in the adsorption tank is saturated, the state of the adsorption tank and the regeneration tank is switched.

[0054] Reference Figure 4 and Figure 5 The drain end of the heatless regenerative dryer 8 is connected to the inside of the absorption tower 61 through the drain pipe 82. The desorbed material from the heatless regenerative dryer 8 is discharged into the absorption tower 61 through the drain pipe 82 to absorb the ethylene oxide in the desorbed material. At the same time, a negative pressure pump 83 is installed on the drain pipe 82 to reduce the air pressure at the drain end of the heatless regenerative dryer 8.

[0055] Reference Figure 4 and Figure 5 Specifically, when the regeneration tank is desorbing the adsorbent, inert gas is discharged from the top of the regeneration pipe 81 through the regeneration pipe 81, and then the moisture in the adsorbent is discharged from the drain pipe 82 at the bottom of the regeneration tank along with the inert gas. At the same time, negative pressure is generated at the bottom of the regeneration tank by the negative pressure pump 83, so as to discharge the gas-liquid mixture at the bottom of the regeneration tank into the absorption tower 61 in a timely manner through the drain pipe 82.

[0056] The working principle of Embodiment 2 of this application is as follows: The gas entering the cooling tower 31 is dried by a heatless regenerative dryer 8, thereby reducing the moisture content of the gas entering the cooling tower 31. At the same time, the desorbed moisture and gas are discharged into the absorption tower 61 to absorb the ethylene oxide therein, thereby improving the service life of the cooling tower 31.

[0057] The above are all preferred embodiments of this application and are not intended to limit the scope of protection of this application. Therefore, all equivalent changes made in accordance with the structure, shape and principle of this application should be covered within the scope of protection of this application.

Claims

1. An ethylene oxide tail gas treatment system, characterized in that: The system includes a cooling assembly (3), a collection assembly (4), and a processing mechanism (6). The cooling assembly (3) is used to cool the exhaust gas discharged from the EO sterilizer (1) and liquefy the ethylene oxide. The collection assembly (4) is used to collect and store the liquefied ethylene oxide. The processing mechanism (6) is used to process the gas discharged from the cooling assembly (3) and the collection assembly (4). The processing mechanism (6) includes: The absorption tower (61) is provided with multiple stages, and the multiple stages of the absorption tower (61) are used to convert ethylene oxide in the gas discharged from the cooling component (3) and the collection component (4) into ethylene glycol layer by layer; Ethylene glycol waste tank (62), the ethylene glycol waste tank (62) is used to store the ethylene glycol solution discharged from the absorption tower (61); Burner (63), the burner (63) is used to combust the gas discharged from the absorption tower (61); The liquid spraying assembly (64) is used to spray the solution in the ethylene glycol waste tank (62) into the burner (63) for combustion.

2. The ethylene oxide tail gas treatment system according to claim 1, characterized in that: The liquid spraying assembly (64) includes: Waste liquid concentrator (641), which is connected to ethylene glycol waste liquid tank (62) through a drain pipe and is used to concentrate the discharged ethylene glycol solution. The heat generated by the burner (63) is used to assist the waste liquid concentrator (641) in heating the ethylene glycol solution. A drain pump (642) is installed on a drain pipe and is used to pump the solution in the ethylene glycol waste tank (62) into the waste concentration tank; A combustion injection pump (643) is connected to a waste liquid concentrator (641) and is used to spray the solution in the waste liquid concentrator (641) into the burner (63) for combustion.

3. The ethylene oxide tail gas treatment system according to claim 1, characterized in that: The absorption tower (61) is a combined bubbling reaction tank. A concentration detector for detecting the concentration of ethylene glycol is installed in the absorption tower (61). The ethylene glycol waste liquid generated in the combined bubbling reaction tank is discharged into the ethylene glycol waste liquid tank (62) through a drainage pump (611). The drainage pump (611) is electrically connected to the concentration detector.

4. The ethylene oxide tail gas treatment system according to claim 1, characterized in that: The EO sterilizer (1) discharges exhaust gas through an exhaust pipe (13). The exhaust pipe (13) is equipped with a pressurization component (2) for protecting and pressurizing the interior of the exhaust pipe (13). The pressurization component (2) includes: An inert gas storage tank, which is connected to an exhaust pipe (13) via an inlet pipe (21) and is used to supply inert gas into the exhaust pipe (13); The first pneumatic ball valve (22) is disposed on the air inlet pipe (21) and is used to open or close the air inlet pipe (21). The first booster (23) is installed on the exhaust pipe (13) and is used to boost the gas inside the exhaust pipe (13) before it is discharged.

5. The ethylene oxide tail gas treatment system according to claim 4, characterized in that: The cooling component (3) includes: Cooling tower (31), which is internally connected to exhaust pipe (13) and is used to cool the pressurized gas and liquefy ethylene oxide; A chiller (32) is connected to a cooling tower (31) and is used to provide a low-temperature environment for the cooling tower (31); The first pipe (33) is installed on the cooling tower (31) and is used to discharge the cooled gas into the absorption tower (61); Discharge pipe (34), which is installed on cooling tower (31) and used to discharge liquefied liquid into collection assembly (4).

6. The ethylene oxide tail gas treatment system according to claim 5, characterized in that: The collection component (4) includes: EO storage tank (41), which is connected to discharge pipe (34) and used to store the liquid discharged from discharge pipe (34); An electronic scale (42) is used to weigh the EO storage tank (41); Vent pipe (43), the vent pipe (43) is installed on the top of the EO storage tank (41) and communicates with the inside of the first pipe (33), the vent pipe (43) is used to discharge the gas in the EO storage tank (41) into the first pipe (33); The second pneumatic ball valve (44) is installed on the vent pipe (43). The second pneumatic ball valve (44) is used to control the opening or closing of the vent pipe (43) and prevent the gas in the first pipe (33) from entering the EO storage tank (41).

7. The ethylene oxide tail gas treatment system according to claim 6, characterized in that: The first tube (33) is provided with a buffer assembly (5) for buffering the discharged gas, the buffer assembly (5) comprising: A flow buffer tank (51) is connected to a first pipe (33) and a vent pipe (43) and is used to buffer the gas discharged from the first pipe (33) and the vent pipe (43); The third pipe (52) is installed on the flow buffer tank (51) and communicates with the inside of the absorption tower (61); A one-way valve (53) is provided on the third pipe (52) and allows gas in the third pipe (52) to enter the absorption tower (61) from the flow buffer tank (51) only; The second flow control valve (54) is installed on the third pipe (52) and located between the check valve (53) and the absorption tower (61). The second flow control valve (54) is used to control the flow in the third pipe (52). A booster pipe (55) is installed on the flow buffer tank (51) and communicates with the inside of the third pipe (52) between the second flow control valve (54) and the absorption tower (61); The third pneumatic ball valve (56) is installed on the booster pipe (55). When the amount of gas in the flow buffer tank (51) is greater than the set value, the third pneumatic ball valve (56) is opened and the booster pipe (55) is closed. The second booster (57) is installed on the booster pipe (55) and is used to boost the gas passing through the third pneumatic ball valve (56).

8. The ethylene oxide tail gas treatment system according to claim 4, characterized in that: The exhaust pipe (13) is equipped with a heatless regenerative dryer (8) for removing water from the pressurized exhaust gas. The inert gas storage tank is connected to the heatless regenerative dryer (8) and assists the heatless regenerative dryer (8) in desorption.

9. The ethylene oxide tail gas treatment system according to claim 8, characterized in that: The drain end of the heatless regenerative dryer (8) is connected to the absorption tower (61) through the drain pipe (82). The desorbed material of the heatless regenerative dryer (8) is discharged into the absorption tower (61) through the drain pipe (82). A negative pressure pump (83) is installed on the drain pipe (82) and the negative pressure pump (83) reduces the air pressure value at the drain end of the heatless regenerative dryer (8).

10. The ethylene oxide tail gas treatment system according to claim 7, characterized in that: The first booster compressor (23) is equipped with a rapid processing component (7) on its exhaust end for processing exhaust gas when the exhaust gas volume is less than a set value. The rapid processing component (7) includes: A pneumatic three-way ball valve (71) is installed on the exhaust end of the first booster (23). The first outlet of the pneumatic three-way ball valve (71) is connected to the inside of the cooling tower (31). When the exhaust gas volume in the exhaust pipe (13) is greater than the set value, the pneumatic three-way ball valve (71) is activated and the exhaust pipe (13) is connected to the inside of the cooling tower (31). The quick pipe (72) is connected to the second outlet of the pneumatic three-way ball valve (71), and the end of the quick pipe (72) away from the pneumatic three-way ball valve (71) is connected to the inside of the flow buffer tank (51).

Images