Hydrogen reduction tail gas recycling system and use method
By condensing, removing dust, freezing and dehydrating, and pressurizing the tail gas from the hydrogen reduction process, the problem of wasted tail gas from the hydrogen reduction reaction was solved, the tail gas was recycled and reused, energy efficiency was improved, and production costs were reduced.
Patent Information
- Authority / Receiving Office
- CN · China
- Patent Type
- Applications(China)
- Current Assignee / Owner
- 中核第七研究设计院有限公司
- Filing Date
- 2026-03-31
- Publication Date
- 2026-05-12
AI Technical Summary
In the uranium conversion production process, excess hydrogen in the tail gas of the hydrogen reduction reaction is directly burned, resulting in energy waste. A method is needed to recover and reuse the tail gas in order to save production costs.
The system, which includes a condensation module, a bubbling tank, a heat exchange module, and a membrane pressure module, enables the recovery and reuse of tail gas from the hydrogen reduction process through condensation, dust removal, freezing and dehydration, and pressurization.
This technology enables the effective recovery of hydrogen reduction reaction tail gas, avoids energy waste, improves energy utilization efficiency, and reduces production costs.
Smart Images
Figure CN122015522A_ABST
Abstract
Description
Technical Field
[0001] This invention relates to the field of uranium conversion technology, and in particular to a system and method for recovering and utilizing hydrogen reduction tail gas. Background Technology
[0002] In the uranium conversion process, hydrogen is used as a reducing agent to reduce uranium trioxide to uranium dioxide. To ensure the conversion rate of the hydrogen reduction reaction, the excess amount of hydrogen is usually controlled at more than 80%.
[0003] The tail gas from the hydrogen reduction process consists of excess hydrogen, nitrogen, water vapor generated during the reaction, and trace amounts of uranium-containing powder. Currently, the tail gas from hydrogen reduction reactions in domestic uranium conversion plants is simply treated before being ignited and discharged into the atmosphere. The excess hydrogen in the tail gas is directly burned, resulting in a significant waste of energy. If the excess hydrogen in the hydrogen reduction tail gas could be recovered and reused, production costs could be greatly reduced. Therefore, this issue urgently needs to be addressed. Summary of the Invention
[0004] The technical problem to be solved by the present invention is to provide a system and method for recovering and utilizing hydrogen reduction tail gas. The method realizes the recovery and utilization of process tail gas by condensing, dust removal, freezing and dehydration, and pressurizing the hydrogen reduction process tail gas, avoiding the direct waste of excess hydrogen in the hydrogen reduction reaction, greatly saving production and operating costs, and improving energy utilization efficiency. To achieve the aforementioned objective, the technical solution of the present invention is as follows: a system and method for recovering and utilizing hydrogen reduction tail gas, comprising a condensation module, a bubbling tank, a heat exchange module, and a membrane pressure module. The condensation module is connected to the condensate storage tank and is used to condense the tail gas generated by the hydrogen reduction process and to introduce the condensate generated during the condensation process into the condensate storage tank. The bubbling tank is connected to the condensation module and is used to remove trace amounts of uranium-containing dust from the tail gas of the hydrogen reduction process. The heat exchange module is connected to the bubbling tank and is used to freeze the gas discharged from the freezing bubbling tank to remove moisture from the gas. The membrane pressure module is connected to the heat exchange module and is used to collect the gas discharged from the heat exchange module and pressurize it to 0.2 MPa to meet the pressure requirements of the hydrogen reduction reaction gas.
[0005] Preferably, the condensation module includes a condenser, a first gas guide pipe, a second gas guide pipe, and a cooling water circulation pipe; the first gas guide pipe is connected to the condenser and introduces the hydrogen reduction process tail gas into the condenser for condensation; the second gas guide pipe is connected to the bubbling tank and is used to introduce the hydrogen reduction process tail gas that has undergone condensation treatment into the bubbling tank; the cooling water circulation pipe is used to introduce cooling water into the condenser; a condensate storage tank connected to the condenser is provided below the condenser.
[0006] Preferably, it also includes an exhaust gas pipeline; one end of the exhaust gas pipeline is connected to the bubbling tank and the other end is connected to the heat exchange module, and the exhaust gas pipeline is equipped with a flow meter and a pneumatic regulating valve, and 15% of the total circulating gas flowing through the exhaust gas pipeline is emptied through the flow meter and the pneumatic regulating valve.
[0007] Preferably, the heat exchange module includes a heat exchanger, a U-shaped exhaust pipe, an ethylene glycol inlet pipe, and an ethylene glycol return pipe; the ethylene glycol inlet pipe and the ethylene glycol return pipe are both connected to the heat exchanger and are used to introduce refrigerant from one side of the heat exchanger and exit it from the other side of the heat exchanger; the heat exchanger is connected to the exhaust gas pipeline and is used to freeze the incoming gas; the U-shaped exhaust pipe is used to exit the frozen gas, and the U-shaped exhaust pipe is equipped with a U-bend and a drain valve; the U-bend and the drain valve are used to guide condensate into a condensate storage tank.
[0008] Preferably, the membrane pressure module includes two gas buffer tanks, a membrane press, and a connecting pipeline; the two gas buffer tanks are located on both sides of the membrane press and are used for pressurizing the incoming gas; the membrane press is used to sequentially connect the two gas buffer tanks and the membrane press, and return the gas to the hydrogen reduction reaction for reuse.
[0009] Preferably, the condenser is a water-cooled shell-and-tube heat exchanger; the cooling water flows through the shell side of the water-cooled shell-and-tube heat exchanger, and the hydrogen reduction process tail gas (containing hydrogen, nitrogen, water vapor, and trace dust) flows through the tube side of the water-cooled shell-and-tube heat exchanger.
[0010] Preferably, the refrigerant in the heat exchanger is -5°C ethylene glycol.
[0011] Preferably, a method for using a system for recovering and utilizing hydrogen reduction tail gas includes the following steps: S1. The tail gas of the hydrogen reduction process is cooled down to 60°C in condenser 1 through heat exchange, and the water vapor in the tail gas is condensed and flows by gravity into the condensate storage tank below. S2. The process tail gas from the condenser outlet is fed into the bubbling tank for bubbling dust removal to remove trace amounts of uranium-containing dust entrained in the process tail gas; the process tail gas from the bubbling tank outlet is discharged through the exhaust tail gas pipeline to achieve 15% discharge of the total circulating gas volume, and the remaining tail gas enters the heat exchanger for further treatment. S3. The process exhaust gas is subjected to freezing and dehydration treatment with -5℃ ethylene glycol in a heat exchanger. Temperature detectors are installed at the inlet and outlet of the heat exchanger to determine whether the exhaust gas has passed the dehydration test. The condensate generated by the freezing and dehydration treatment flows into the condensate storage tank at the U-bend of the U-shaped exhaust pipe and the drain valve.
[0012] S4. The process tail gas from the heat exchanger outlet enters the gas buffer tank on one side of the membrane press for pressure stabilization, and then enters the membrane press for pressurization. After the process tail gas is pressurized to 0.2MPa, it enters the gas buffer tank on the other side of the membrane press. S5. After the process tail gas is stabilized in the gas buffer tank, fresh hydrogen is added and transported back to the hydrogen reduction reactor for reuse through the connecting pipeline.
[0013] The beneficial effects of this invention are reflected in: The method provided by this invention achieves the recovery and utilization of excess hydrogen by treating the tail gas of the hydrogen reduction process through condensation, bubbling dust removal, cooling and dehydration, and pressurization, thus avoiding a huge waste of energy. Attached Figure Description
[0014] Figure 1 This is a simplified process flow diagram of the present invention.
[0015] Figure labels and descriptions: 1. Condenser; 2. Bubble bath; 3. Heat exchanger; 4. Buffer tank; 5. Membrane press. Detailed Implementation
[0016] The technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only a part of the embodiments of the present invention, and not all of them. Unless otherwise specified, the embodiments and features in the embodiments of this application can be combined with each other. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention.
[0017] Example 1 like Figure 1 As shown, the present invention provides a system and method for recovering and utilizing hydrogen reduction tail gas, including a condensation module, a bubbling tank 2, a heat exchange module and a membrane pressure module.
[0018] The condensation module is connected to the condensate storage tank and is used to condense the tail gas generated by the hydrogen reduction process and to introduce the condensate generated during the condensation process into the condensate storage tank.
[0019] The condensation module includes a condenser 1, a first gas guide pipe, a second gas guide pipe, and a cooling water circulation pipe. The first gas guide pipe is connected to the condenser 1 and introduces the hydrogen reduction process tail gas into the condenser 1 for condensation. The second gas guide pipe is connected to the bubbling tank 2 and is used to introduce the condensed hydrogen reduction process tail gas into the bubbling tank 2. The cooling water circulation pipe is used to introduce cooling water into the condenser 1. A condensate storage tank is provided below the condenser 1 and is connected to it. The condenser 1 is a water-cooled shell-and-tube heat exchanger; the cooling water flows through the shell side of the water-cooled shell-and-tube heat exchanger, and the hydrogen reduction process tail gas (containing hydrogen, nitrogen, water vapor, and trace dust) flows through the tube side of the water-cooled shell-and-tube heat exchanger.
[0020] Bubble tank 2 is connected to the condensation module and is used to remove trace amounts of uranium-containing dust from the tail gas of the hydrogen reduction process.
[0021] It also includes an exhaust gas pipeline; one end of the exhaust gas pipeline is connected to the bubbling tank 2, and the other end is connected to the heat exchange module. The exhaust gas pipeline is equipped with a flow meter and a pneumatic regulating valve, and 15% of the total circulating gas flowing through the exhaust gas pipeline is emptied through the flow meter and the pneumatic regulating valve.
[0022] The heat exchange module is connected to the bubbling tank 2 and is used to freeze the gas discharged from the refrigeration bubbling tank 2 to remove moisture from the gas.
[0023] The heat exchange module includes a heat exchanger 3, a U-shaped exhaust pipe, an ethylene glycol inlet pipe, and an ethylene glycol return pipe. The ethylene glycol inlet pipe and the ethylene glycol return pipe are both connected to the heat exchanger 3 and are used to introduce the refrigerant from one side of the heat exchanger 3 and exit it from the other side of the heat exchanger 3. The refrigerant of the heat exchanger 3 is -5℃ ethylene glycol.
[0024] Heat exchanger 3 is connected to the exhaust gas pipeline and is used to freeze the incoming gas; the U-shaped exhaust pipe is used to discharge the frozen gas, and the U-shaped exhaust pipe is equipped with a U-shaped bend and a drain valve; the U-shaped bend and the drain valve are used to guide the condensate into the condensate storage tank.
[0025] The membrane pressure module is connected to the heat exchange module and is used to collect the gas discharged from the heat exchange module and pressurize it to 0.2 MPa to meet the pressure requirements of the hydrogen reduction reaction gas.
[0026] The membrane pressure module includes two gas buffer tanks 4, a membrane press 5, and connecting pipelines; the two gas buffer tanks 4 are located on both sides of the membrane press 5, and are used to pressurize the incoming gas; the membrane press 5 is used to pressurize the incoming gas; the connecting pipelines are used to connect the two gas buffer tanks 4 and the membrane press 5 in sequence, and return the gas to the hydrogen reduction reaction for reuse.
[0027] Example 2 A method for using a system for recovering and utilizing hydrogen reduction tail gas includes the following steps: S1. The tail gas of the hydrogen reduction process is cooled down to 60°C in condenser 1 through heat exchange, and the water vapor in the tail gas is condensed and flows by gravity into the condensate storage tank below. S2. The process tail gas from the outlet of condenser 1 is fed into bubble tank 2 for bubble dust removal to remove trace amounts of uranium-containing dust entrained in the process tail gas. The process tail gas from the outlet of bubble tank 2 is discharged in the exhaust tail gas pipeline to achieve 15% of the total circulating gas volume. The remaining tail gas enters heat exchanger 4 for further treatment. S3. The process exhaust gas is subjected to freezing and dehydration treatment with -5℃ ethylene glycol in heat exchanger 4. Temperature detectors are set at the inlet and outlet of heat exchanger 4 to determine whether the exhaust gas has passed the dehydration test. The condensate generated by the freezing and dehydration treatment flows into the condensate storage tank at the U-bend of the U-shaped exhaust pipe and the drain valve.
[0028] S4. The process tail gas from the outlet of heat exchanger 4 enters the gas buffer tank 4 on one side of the membrane press 5 for pressure stabilization, and then enters the membrane press 5 for pressurization. After the process tail gas is pressurized to 0.2MPa, it enters the gas buffer tank on the other side of the membrane press 5. S5. After the process tail gas is stabilized in the gas buffer tank 4, fresh hydrogen is added and transported back to the hydrogen reduction reactor for reuse through the connecting pipeline.
[0029] The above description is only a preferred embodiment of the present invention and is not intended to limit the present invention. Any modifications, equivalent substitutions, improvements, etc., made within the spirit and principles of the present invention should be included within the protection scope of the present invention.
Claims
1. A system for recovering and utilizing hydrogen reduction tail gas, characterized in that, Includes a condensation module, a bubbling tank (2), a heat exchange module, and a membrane pressure module; The condensation module is connected to the condensate storage tank and is used to condense the tail gas generated by the hydrogen reduction process and to introduce the condensate generated during the condensation process into the condensate storage tank. The bubbling tank (2) is connected to the condensation module and is used to remove trace amounts of uranium-containing dust from the tail gas of the hydrogen reduction process. The heat exchange module is connected to the bubbling tank (2) and is used to freeze the gas discharged from the bubbling tank (2) to remove moisture from the gas; The membrane pressure module is connected to the heat exchange module and is used to collect the gas discharged from the heat exchange module and pressurize it to 0.2 MPa.
2. The system for recovering and utilizing hydrogen reduction tail gas according to claim 1, characterized in that, The condensation module includes a condenser (1), a first gas guide pipe, a second gas guide pipe, and a cooling water circulation pipe; the first gas guide pipe is connected to the condenser (1) and introduces the hydrogen reduction process tail gas into the condenser (1) for condensation; the second gas guide pipe is connected to the bubbling tank (2) and is used to introduce the hydrogen reduction process tail gas that has completed the condensation treatment into the bubbling tank (2); The cooling water circulation pipe is used to introduce cooling water into the condenser (1); a condensate storage tank connected to the condenser (1) is provided below the condenser (1).
3. The system for recovering and utilizing hydrogen reduction tail gas according to claim 1, characterized in that, It also includes an exhaust gas pipeline; one end of the exhaust gas pipeline is connected to the bubbling tank (2), and the other end is connected to the heat exchange module. The exhaust gas pipeline is equipped with a flow meter and a pneumatic regulating valve, and 15% of the total circulating gas flowing through the exhaust gas pipeline is emptied through the flow meter and the pneumatic regulating valve.
4. The system for recovering and utilizing hydrogen reduction tail gas according to claim 1, characterized in that, The heat exchange module includes a heat exchanger (3), a U-shaped exhaust pipe, an ethylene glycol inlet pipe, and an ethylene glycol return pipe; the ethylene glycol inlet pipe and the ethylene glycol return pipe are both connected to the heat exchanger (3) and are used to introduce the refrigerant from one side of the heat exchanger (3) and export it from the other side. The heat exchanger (3) is connected to the exhaust gas pipeline and is used to freeze the incoming gas; the U-shaped exhaust pipe is used to export the frozen gas, and the U-shaped exhaust pipe is equipped with a U-shaped bend and a drain valve; the U-shaped bend and the drain valve are used to import condensate into the condensate storage tank.
5. The system for recovering and utilizing hydrogen reduction tail gas according to claim 4, characterized in that, The membrane pressure module includes two gas buffer tanks (4), a membrane press (5), and a connecting pipeline; the two gas buffer tanks (4) are located on both sides of the membrane press (5) and are used to pressurize the incoming gas; the membrane press (5) is used to connect the two gas buffer tanks (4) and the membrane press (5) in sequence, and return the gas to the hydrogen reduction reaction for reuse.
6. The system for recovering and utilizing hydrogen reduction tail gas according to claim 2, characterized in that, The condenser (1) is a water-cooled shell-and-tube heat exchanger; the cooling water flows through the shell side of the water-cooled shell-and-tube heat exchanger, and the hydrogen reduction process tail gas flows through the tube side of the water-cooled shell-and-tube heat exchanger.
7. A system for recovering and utilizing hydrogen reduction tail gas according to claim 4, characterized in that, The refrigerant in the heat exchanger (3) is ethylene glycol at -5℃.
8. A method for using a system for recovering and utilizing hydrogen reduction tail gas according to any one of claims 1-7, characterized in that, Includes the following steps: S1. The tail gas of the hydrogen reduction process is cooled down by heat exchange in the condenser (1) to 60°C, and the water vapor in the tail gas is condensed and flows by gravity into the condensate storage tank below. S2. The process tail gas from the outlet of the condenser (1) is fed into the bubbling tank (2) for bubbling dust removal to remove trace amounts of uranium-containing dust carried in the process tail gas; the process tail gas from the outlet of the bubbling tank (2) is discharged in the exhaust tail gas pipeline to achieve 15% of the total circulating gas volume, and the remaining tail gas enters the heat exchanger (4) for further processing. S3. The process tail gas is subjected to freezing and dehydration treatment with -5℃ ethylene glycol in the heat exchanger (4), and temperature detection is set at the inlet and outlet of the heat exchanger (4) to determine whether the tail gas is qualified for dehydration. The condensate generated by the freezing and dehydration treatment flows into the condensate storage tank at the U-shaped bend of the U-shaped exhaust pipe and the drain valve. S4. The process tail gas from the heat exchanger (4) outlet enters the gas buffer tank (4) on one side of the membrane press (5) for pressure stabilization, and then enters the membrane press (5) for pressurization. After the process tail gas is pressurized to 0.2MPa, it enters the gas buffer tank on the other side of the membrane press (5). S5. After the process tail gas is stabilized in the gas buffer tank (4), fresh hydrogen is added and transported back to the hydrogen reduction reactor through the connecting pipeline for reuse.