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CN-121988167-A - System and process for producing deuterium-enriched water by combining chemical exchange and liquid ammonia rectification

CN121988167ACN 121988167 ACN121988167 ACN 121988167ACN-121988167-A

Abstract

The invention provides a system for producing deuterium-enriched water by combining chemical exchange and liquid ammonia rectification, which comprises an ammonia A2 storage unit, ammonia water exchange equipment, liquid ammonia rectification equipment and water ammonia exchange equipment, wherein the three working procedures of ammonia water exchange, liquid ammonia rectification and water ammonia exchange are coupled in series, so that a complete hydrogen isotope (deuterium) enrichment path is constructed. According to the path, deuterium is efficiently transferred from high-boiling-point raw material water to a low-boiling-point ammonia medium through ammonia water exchange, then, low-energy consumption and high-magnification deuterium enrichment is realized in an N-level rectifying tower by utilizing the low-boiling-point characteristic of liquid ammonia through liquid ammonia rectification, finally, high-deuteration-degree ammonia is efficiently converted back into high-deuteration-degree deuterium-enriched water through reverse water-ammonia exchange, the cooperative transfer of material flow and co-position element flow is obviously optimized, and the directional and gradual enrichment of deuterium in the material flow process is realized.

Inventors

  • GAO ZHANGHUA
  • WU TAO
  • CAO BOTAO
  • LIU KEKE
  • TANG JIANBO

Assignees

  • 宁波萃英化学技术有限公司

Dates

Publication Date
20260508
Application Date
20260130

Claims (20)

  1. 1. A system for producing deuterium-enriched water by combining chemical exchange and liquid ammonia rectification, which is characterized by comprising an ammonia A2 storage unit (2400), an ammonia water exchange device, a liquid ammonia rectification device and a water ammonia exchange device; The ammonia water exchange equipment comprises an absorption unit A (2100), an exchange unit A (2200) and a decomposition unit A (2300) which are sequentially communicated, wherein ammonia A2 output from the upper part of the absorption unit A (2100) is introduced into an ammonia A2 storage unit (2400); The liquid ammonia rectification equipment comprises an N-level rectification unit (3100), wherein the N-level rectification unit (3100) comprises an N-level rectification module, any rectification template comprises a rectification tower (3110) and a rectification module reboiler (3120) communicated with the rectification tower (3110), a heavy component extraction outlet (3111) of the rectification tower (3110) of a front rectification module is communicated with a raw material inlet (3113) of the rectification tower (3110) of a rear rectification module for adjacent two-level rectification modules, a light component reflux outlet (3112) of the rectification tower (3110) of the front rectification module is communicated with a light component extraction outlet (3114) of the rectification tower (3110) of the rear rectification module, a raw material inlet (3113) of the 1 st rectification module is communicated with an outlet of an ammonia A2 storage unit (2400), and the N-level rectification unit (3100) is A2-10-level rectification unit; The water ammonia exchange device comprises an absorption unit (4100), an exchange unit (4200) and a decomposition unit (4300) which are sequentially communicated, wherein deuterated ammonia output from the upper part of the absorption unit (4100) is introduced into an ammonia A2 storage unit (2400), the exchange unit (4200) comprises an exchange tower (4210) and a deuterium-enriched ammonia A3 input assembly which are communicated with the absorption unit (4100), a deuterium-enriched ammonia A3 gas inlet is arranged at the lower part of the exchange tower (4210), and deuterium-enriched ammonia A3 extracted from a heavy component extraction outlet (3111) of an Nth-stage rectification module is input into the exchange tower (4210) through the deuterium-enriched ammonia A3 gas inlet by the deuterium-enriched ammonia A3 input assembly.
  2. 2. The system for producing deuterium-enriched water by combining chemical exchange and liquid ammonia rectification according to claim 1, characterized in that the liquid ammonia rectification equipment further comprises a compression circulation unit (3200), the compression circulation unit (3200) comprises a first-stage compressor (3210) and a gas-liquid separator (3220), a light component extraction outlet (3114) of a first-stage rectification module is communicated with an inlet of the first-stage compressor (3210), an outlet of the first-stage compressor (3210) is communicated with an inlet of a rectification module reboiler (3120), and an outlet of the rectification module reboiler (3120) is communicated with an inlet of the gas-liquid separator (3220).
  3. 3. The system for producing deuterium enriched water by means of chemical exchange and liquid ammonia rectification according to claim 2, characterized in that said first stage rectification module also has a light component integrated return (3115); The liquid phase outlet of the gas-liquid separator (3220) is divided into two paths, wherein the first path is communicated with a gas inlet at the lower part of the exchange tower A (2210) through a low-deuterium ammonia A1 input assembly, or the first path is connected with a low-deuterium ammonia A1 storage unit (3400) of liquid ammonia rectifying equipment, and the low-deuterium ammonia A1 storage unit (3400) is communicated with a gas inlet of the exchange tower A (2210) through the low-deuterium ammonia A1 input assembly; the second path is communicated with a light component comprehensive reflux port (3115) of a rectifying tower (3110) of the first-stage rectifying module.
  4. 4. A system for producing deuterium enriched water by combining chemical exchange and liquid ammonia rectification according to any one of claims 1-3, characterized in that any one of said rectification columns (3110) comprises any one or more of the following (I) - (XI): (I) The heavy component extraction port (3111) is provided at the lower part or bottom of the rectifying column (3110); (II) the light component reflux port (3112) is provided at the lower part or bottom of the rectifying column (3110); (III) the raw material inlet (3113) is provided at the middle, upper or top of the rectifying column (3110); (IV) the light component extraction port (3114) is provided at an upper portion or a top portion of the rectifying column (3110); (V) a light component comprehensive reflux port (3115) of a rectifying tower (3110) of the first stage rectifying module is disposed at an upper portion or a top portion of the rectifying tower (3110); (VI) the inlet of the rectification module reboiler (3120) is provided at the upper part or the top of the rectification module reboiler (3120); (VII) the outlet of the rectification module reboiler (3120) is provided at the lower part or bottom of the rectification module reboiler (3120); (VIII) the ammonia A2 storage unit (2400) is in communication with a feed inlet (3113) of a first stage rectification module; The outlet of the first-stage compressor (3210) is communicated with the inlet of a rectifying module reboiler (3120) of each rectifying module, and the outlet of the rectifying module reboiler (3120) of each rectifying module is communicated with the inlet of a gas-liquid separator (3220); (X) the liquid ammonia rectification apparatus further comprises a deuterium enriched ammonia A3 storage unit (3300), said deuterium enriched ammonia A3 storage unit (3300) being in communication with the heavy component extraction outlet (3111) of the N-th stage rectification module; meanwhile, the deuterium enriched ammonia A3 storage unit (3300) is communicated with a gas inlet of the exchange tower (4210) through a deuterium enriched ammonia A3 input component; (XI) the rectifying tower (3110) of the first-stage rectifying module to the rectifying tower (3110) of the N-th-stage rectifying module, the tower diameter is gradually reduced.
  5. 5. The system for producing deuterium enriched water by combining chemical exchange and liquid ammonia rectification according to claim 4, characterized in that said compression cycle unit (3200) further comprises a secondary compressor (3230) and a heat exchanger (3240), the gas phase outlet of said gas-liquid separator (3220) is communicated with the inlet of the secondary compressor (3230), and the outlet of the secondary compressor (3230) is communicated with the reflux port of the gas-liquid separator (3220) through the heat exchanger (3240).
  6. 6. The system for producing deuterium-enriched water by combining chemical exchange and liquid ammonia rectification according to any one of claims 1-3 and 5, characterized in that said liquid ammonia rectification apparatus further comprises any one or more of the following (a) - (e): (a) The heavy component extraction outlet (3111) of the rectifying tower (3110) of the front rectifying module is communicated with the raw material inlet (3113) of the rectifying tower (3110) of the rear rectifying module through a pump; (b) A flowmeter is arranged on a communication pipeline between a heavy component extraction outlet (3111) of a rectifying tower (3110) of the front rectifying module and a raw material inlet (3113) of the rectifying tower (3110) of the rear rectifying module; (c) The liquid phase outlet of the gas-liquid separator (3220) is communicated with a light component comprehensive reflux port (3115) of the first-stage rectification module through a pump; (d) A flow meter is arranged on a communication pipeline between a liquid phase outlet of the gas-liquid separator (3220) and a light component comprehensive reflux port (3115) of the first-stage rectifying module; (e) The ammonia A2 storage unit (2400) is in communication with a feed inlet (3113) of the first stage rectification module via a pump.
  7. 7. The system for producing deuterium enriched water by combining chemical exchange and liquid ammonia rectification according to any one of claims 1-3 and 5, characterized in that the absorption unit A (2100) comprises a third condenser A (2120) and an absorption tower A (2110) which are communicated in sequence, wherein the upper part of the absorption tower A (2110) is provided with a water W1 inlet and a gas outlet, and the lower part of the absorption tower A (2110) is provided with a liquid phase outlet and a gas inlet, the absorption tower A (2110) is communicated with the third condenser A (2120) through a deuterated ammonia outlet at the upper part of the absorption tower A (2110), and the third condenser A (2120) is communicated with an ammonia A2 storage unit (2400); The exchange unit A (2200) comprises an exchange tower A (2210) and a low-deuterium ammonia A1 input component, wherein a gas outlet and a liquid phase inlet are arranged at the upper part of the exchange tower A (2210), a low-deuterium ammonia A1 gas inlet, a gas inlet and a liquid phase outlet are arranged at the lower part of the exchange tower A (2210), the low-deuterium ammonia A1 gas inlet at the lower part of the exchange tower A (2210) is communicated with the low-deuterium ammonia A1 input component, the gas outlet at the upper part of the exchange tower A (2210) is communicated with the gas inlet at the lower part of the absorption tower A (2110), and the liquid phase inlet at the upper part of the exchange tower A (2210) is communicated with the liquid phase outlet at the lower part of the absorption tower A (2110); The decomposing unit A (2300) comprises a second condenser A (2310), a decomposing tower A (2320) and a reboiler A (2330) which are sequentially communicated, wherein a liquid phase outlet is arranged at the lower part of the decomposing tower A (2320), a liquid phase inlet and a gas outlet are arranged at the upper part of the decomposing tower A (2320), the liquid phase outlet at the lower part of the decomposing tower A (2320) is communicated with the reboiler A (2330), the liquid phase inlet at the upper part of the decomposing tower A (2320) is communicated with the liquid phase outlet at the lower part of the exchanging tower A (2210), the gas outlet at the upper part of the decomposing tower A (2320) is communicated with the gas inlet at the lower part of the exchanging tower A (2210), the reboiler A (2330) is provided with a treatment liquid outlet, and the gas outlet at the upper part of the decomposing tower A (2320) is communicated with the gas inlet at the lower part of the exchanging tower A (2210).
  8. 8. The system for producing deuterium enriched water by chemical exchange and liquid ammonia rectification combination according to claim 7, characterized in that said ammonia water exchange device further comprises any one or more of the following (I) - (IX): (I) The absorption unit A (2100) comprises a water W1 feed pump A (2130), wherein the water W1 feed pump A (2130) is communicated with a water W1 inlet at the upper part of the absorption tower A (2110); (II) a fourth flow component A (2230) is arranged between the gas outlet at the upper part of the exchange tower A (2210) and the gas inlet at the lower part of the absorption tower A (2110); (III) a fifth flow assembly a (2140) is arranged between the third condenser a (2120) and the ammonia A2 storage unit (2400); (IV) a fourth temperature detection component A is arranged between a liquid phase inlet at the upper part of the exchange tower A (2210) and a liquid phase outlet at the lower part of the absorption tower A (2110); (V) the deuterium depleted ammonia A1 input assembly is in communication with a deuterium depleted ammonia A1 storage unit (3400), said third flow assembly a being arranged between deuterium depleted ammonia A1 storage unit (3400) and a deuterium depleted ammonia A1 gas inlet in the lower part of exchange column a (2210); (VI) a second flow assembly a is disposed between the second condenser a (2310) and the gas inlet of the exchange column a (2210); (VII) a second temperature detection component A is arranged between a liquid phase inlet at the upper part of the decomposition tower A (2320) and a liquid phase outlet at the lower part of the exchange tower A (2210); The ammonia water exchange device comprises a low-deuterium water W2 recovery unit A (2500) and a low-deuterium water W2 discharge pump A (2520), wherein the low-deuterium water W2 recovery unit A (2500) comprises a first condenser A (2510); The deuterium depleted water W2 discharging pump A (2520) is communicated with the first condenser A (2510), and a treatment fluid outlet of the reboiler A (2330) is communicated with the first condenser A (2510); A first flow assembly a is disposed between the treatment fluid outlet of reboiler a (2330) and the first condenser a (2510).
  9. 9. The system for producing deuterium enriched water by combining chemical exchange and liquid ammonia rectification according to any one of claims 1-3, 5 and 8, characterized in that the absorption unit (4100) comprises a third condenser (4120) and an absorption tower (4110) which are communicated in sequence, wherein the upper part of the absorption tower (4110) is provided with a water W3 inlet and a gas outlet, and the lower part of the absorption tower (4110) is provided with a liquid phase outlet and a gas inlet, the absorption tower (4110) is communicated with the third condenser (4120) through the gas outlet at the upper part of the absorption tower, and the third condenser (4120) is communicated with an ammonia A2 storage unit (2400); The upper part of an exchange tower (4210) of the exchange unit (4200) is provided with a gas outlet and a liquid phase inlet, and the lower part of the exchange tower is provided with a deuterium-enriched ammonia A3 gas inlet, a gas inlet and a liquid phase outlet, wherein the deuterium-enriched ammonia A3 gas inlet at the lower part of the exchange tower (4210) is communicated with a deuterium-enriched ammonia A3 input assembly, the gas outlet at the upper part of the exchange tower (4210) is communicated with the gas inlet at the lower part of an absorption tower (4110), and the liquid phase inlet at the upper part of the exchange tower (4210) is communicated with the liquid phase outlet at the lower part of the absorption tower (4110); The decomposing unit (4300) comprises a second condenser (4310), a decomposing tower (4320) and a reboiler (4330) which are sequentially communicated, wherein a liquid phase outlet is arranged at the lower part of the decomposing tower (4320), a liquid phase inlet and a gas outlet are arranged at the upper part of the decomposing tower (4320), the liquid phase outlet at the lower part of the decomposing tower (4320) is communicated with the reboiler (4330), the liquid phase inlet at the upper part of the decomposing tower (4320) is communicated with the liquid phase outlet at the lower part of the exchange tower (4210), the gas outlet at the upper part of the decomposing tower (4320) is communicated with the gas inlet at the lower part of the exchange tower (4210), the reboiler (4330) is provided with a treatment liquid outlet, the gas outlet at the upper part of the decomposing tower (4320) is communicated with the second condenser (4310), and the gas outlet at the upper part of the second condenser (4310) is communicated with the gas inlet at the lower part of the exchange tower (4210).
  10. 10. The system for producing deuterium-enriched water by means of chemical exchange and liquid ammonia rectification according to claim 9, characterized in that said water-ammonia exchange device comprises any one or more of the following (I) - (IX): (I) The absorption unit (4100) comprises a water W3 feed pump (4130), wherein the water W3 feed pump (4130) is communicated with a water W3 inlet at the upper part of the absorption tower (4110); (II) a fourth flow component (4230) is arranged between a gas outlet at the upper part of the exchange tower (4210) and a gas inlet at the lower part of the absorption tower (4110); (III) a fifth flow assembly (4140) is provided between the third condenser (4120) and the ammonia A2 storage unit (2400); (IV) a fourth temperature detection component is arranged between a liquid phase inlet at the upper part of the exchange tower (4210) and a liquid phase outlet at the lower part of the absorption tower (4110); (V) the deuterium enriched ammonia A3 input component comprises a third flow component, wherein the third flow component is arranged between a heavy component extraction outlet (3111) of the N-th stage rectification module and a deuterium enriched ammonia A3 gas inlet at the lower part of the exchange tower (4210); Or the third flow component is arranged between the deuterium enriched ammonia A3 storage unit (3300) and a deuterium enriched ammonia A3 gas inlet at the lower part of the exchange tower (4210); (VI) a second flow assembly is disposed between the second condenser (4310) and the gas inlet of the exchange column (4210); A second temperature detection component is arranged between a liquid phase inlet at the upper part of the decomposing tower (4320) and a liquid phase outlet at the lower part of the exchange tower (4210); (VIII) the water ammonia exchange device further comprises a deuterium enriched water W4 storage unit (4400), a deuterium enriched water W4 discharge pump (4420), said deuterium enriched water W4 storage unit (4400) comprising a first condenser (4410); the deuterium enriched water W4 discharging pump (4420) is communicated with the first condenser (4410), and the heavy water treatment liquid outlet of the reboiler (4330) is communicated with the first condenser (4410); A first flow assembly is disposed between the process fluid outlet of the reboiler (4330) and the first condenser (4410).
  11. 11. A method for producing deuterium-enriched water by combining chemical exchange and liquid ammonia rectification, which is characterized by comprising the following steps: (1) Ammonia exchange The water W1 enters an absorption tower A (2110) from the upper part of the absorption tower A (2110), the gas of the exchange tower A enters the absorption tower A (2110) from the lower part of the absorption tower A (2110), the water W1 and the gas of the exchange tower A are in countercurrent contact in the absorption tower A (2110) to form an absorption tower A treatment liquid and an ammonia A2 gas product, and the ammonia A2 gas product is condensed and then is introduced into an ammonia A2 storage unit (2400); the method comprises the steps that an absorption tower A treatment liquid enters an exchange tower A (2210) from the upper part of the exchange tower A (2210), low-deuterium ammonia A1 enters the exchange tower A (2210) from the lower part of the exchange tower A (2210), the absorption tower A treatment liquid and the low-deuterium ammonia A1 are in countercurrent contact in the exchange tower A (2210), and meanwhile, an exchange tower A treatment liquid and an exchange tower A gas are formed; The treatment liquid of the exchange tower A enters a decomposition tower A (2320) from the upper part of the decomposition tower A (2320) and is decomposed into gas of the decomposition tower A in the decomposition tower A (2320) at high temperature, wherein the treatment liquid of the decomposition tower A enters a reboiler A (2330) to discharge low-deuterium water W2; (2) Liquid ammonia rectification Ammonia A2 in the ammonia A2 storage unit (2400) enters the rectifying column (3110) via the raw material inlet (3113) of the first stage rectifying module; heavy components extracted from a rectifying tower (3110) of the front rectifying module are introduced into a rectifying tower (3110) of the rear rectifying module, light components extracted from the rectifying tower (3110) of the rear rectifying module are refluxed to the rectifying tower (3110) of the front rectifying module, and deuterium-enriched ammonia A3 products are extracted from the rectifying tower (3110) of the Nth rectifying module; Light components extracted from a rectifying tower (3110) of the first-stage rectifying module are pressurized and heated by a first-stage compressor (3210) and then are led into a rectifying module reboiler (3120) of an N-stage rectifying unit (3100) in N paths, discharged materials after heat exchange in the rectifying module reboiler (3120) are led into a gas-liquid separator (3220) for treatment, and liquid phases extracted from the gas-liquid separator (3220) are returned to the rectifying tower (3110) of the first-stage rectifying module; (3) Water ammonia exchange The water W3 enters an absorption tower (4110) from the upper part of the absorption tower (4110), the exchange tower gas enters the absorption tower (4110) from the lower part of the absorption tower (4110), the water W3 and the exchange tower gas are in countercurrent contact in the absorption tower (4110) to form absorption tower treatment liquid and ammonia A2 gas, and the ammonia A2 gas is condensed and then is introduced into an ammonia A2 storage unit (2400); The method comprises the steps that an absorption tower treatment liquid enters an exchange tower (4210) from the upper part of the exchange tower (4210), deuterium enriched ammonia A3 enters the exchange tower (4210) from the lower part of the exchange tower (4210), and the absorption tower treatment liquid and deuterium enriched ammonia A3 are in countercurrent contact in the exchange tower (4210) to form an exchange tower treatment liquid and exchange tower gas; The exchange tower treatment liquid enters a decomposition tower (4320) from the upper part of the decomposition tower (4320), is decomposed into decomposition tower gas at high temperature in the decomposition tower (4320), and enters a reboiler (4330) to discharge deuterium enriched water W4 as a final product.
  12. 12. The method for producing deuterium enriched water by combining chemical exchange and liquid ammonia distillation according to claim 11, wherein (2) in liquid ammonia distillation, the liquid phase produced by the gas-liquid separator (3220) is split into two paths, the first path is returned to the exchange column a (2210), and the second path is returned to the distillation column (3110) of the first-stage distillation module.
  13. 13. The method for producing deuterium enriched water by combining chemical exchange and liquid ammonia rectification according to claim 12, wherein (1) in ammonia exchange, O, M, Z, E satisfy the following relation: , And O + z1 = E + M, Wherein O is the liquid inlet flow rate of water W1 entering an absorption tower A (2110), kg/h, D O is the deuteration degree of water W1; Z1 is the conveying flow rate of the liquid phase first path liquid low deuterium ammonia A1 extracted by a gas-liquid separator (3220), kg/h, D Z1 is the deuteration degree of the liquid phase first path liquid low deuterium ammonia A1; e is the flow rate of the low deuterium depleted water W2 discharged from the reboiler A (2330), kg/h, D E is the deuteration degree of the low deuterium depleted water W2; m is the discharge rate of ammonia A2 discharged from the absorption tower A (2110), kg/h, D M is the deuteration degree of ammonia A2; M0 is the relative molecular mass of NH 3 and M1 is the relative molecular mass of H 2 O.
  14. 14. The method for producing deuterium-enriched water by combining chemical exchange and liquid ammonia rectification according to claim 12, wherein (1) ammonia water exchange further comprises any one or more of the following conditions (I) - (V): (I) The gas of the decomposing tower A is condensed and then is introduced into the exchange tower A (2210) from the bottom of the exchange tower A (2210); (II) the treatment liquid of the decomposing tower A enters a reboiler A (2330) to be discharged and then is subjected to condensation treatment; (III) the feeding molar ratio of the low deuterium ammonia A1 to the water W1 is 1 (1.5-2.0); (IV) the temperature range in the absorption tower A (2110) is-10-30 ℃, the liquid inlet temperature of the treatment liquid in the absorption tower A into the exchange tower A (2210) is 10-20 ℃, and the temperature range in the exchange tower A (2210) is 0-80 ℃; and (V) the temperature range in the decomposition tower A (2320) is 110-150 ℃, and the temperature of the liquid entering the decomposition tower A (2320) is 50-80 ℃.
  15. 15. The method for producing deuterium-enriched water by combining chemical exchange and liquid ammonia rectification according to any one of claims 11-13, characterized in that (2) any one or more of the following conditions (I) - (V) are satisfied in liquid ammonia rectification: (I) Light components extracted from a rectifying tower (3110) of the first-stage rectifying module are processed by a first-stage compressor (3210) and then are led into an N-stage rectifying module reboiler (3120) in N paths; (II) discharging after heat exchange in a rectifying module reboiler (3120) is introduced into a gas-liquid separator (3220) for treatment; (III) discharging materials after heat exchange in a rectifying module reboiler (3120) are introduced into a gas-liquid separator (3220) for treatment, a secondary compressor (3230) is utilized to carry out pressurizing and heating treatment on gas phase extracted by the gas-liquid separator (3220), and then the gas phase is returned to the gas-liquid separator (3220) after heat exchange treatment; In the N-level rectifying unit (3100), the top pressure of the rectifying tower (3110) of any one-level rectifying module is 0.2-0.5 MPa; (V) the first path of the liquid phase extracted by the gas-liquid separator (3220) is conveyed to the low-deuterium ammonia A1 storage unit (3400) and then is introduced into the exchange column A through the low-deuterium ammonia A1 gas inlet through the low-deuterium ammonia A1 input component (2210), or the first path is directly introduced into the exchange column A through the low-deuterium ammonia A1 gas inlet through the low-deuterium ammonia A1 input component (2210).
  16. 16. The method for producing deuterium enriched water by combining chemical exchange and liquid ammonia distillation according to claim 15, wherein (2) in liquid ammonia distillation, X, Y, Z1 satisfies the following relationship: , And is also provided with , Wherein X is the feeding flow rate of ammonia A2, kg/h, and Dx is the deuteration degree of ammonia A2; A Y deuterium enriched ammonia A3 storage unit (3300) feeding flow rate of deuterium enriched ammonia A3, kg/h; D Y is the deuteration of deuterium-enriched ammonia A3; Z1 is the conveying flow rate of the liquid phase first path liquid low deuterium ammonia A1 extracted by a gas-liquid separator (3220), kg/h, D Z1 is the deuteration degree of the liquid phase first path liquid low deuterium ammonia A1; M0 is the relative molecular mass of NH 3 .
  17. 17. The method for producing deuterium enriched water by combining chemical exchange and liquid ammonia distillation according to claim 16, wherein the conveying rate of the first path of liquid material of the liquid phase extracted by the gas-liquid separator (3220) is Z1, the feeding rate of the second path of liquid material flowing back to the rectifying tower (3110) of the first-stage rectifying module is Z2, and Z1: Z2 is 1 (20-60).
  18. 18. The method for producing deuterium-enriched water by combining chemical exchange and liquid ammonia rectification according to any one of claims 11-14 and 16-17, characterized in that (2) in liquid ammonia rectification, the pressure at the inlet of the primary compressor (3210) is 0.1-0.5 mpa, and the pressure at the outlet is 0.15-1.0 mpa; And/or the pressure of the inlet of the secondary compressor (3230) is 0.3-0.5 MPa, and the pressure of the outlet is 1.3-1.6 MPa.
  19. 19. The method for producing deuterium-enriched water by combining chemical exchange and liquid ammonia rectification according to any one of claims 11-14 and 16-17, wherein (3) in water ammonia exchange, P, Y, N, F satisfies the following relation: , And P + Y = F + N, Wherein P is the feed rate of water W3 to absorber (4110), kg/h, D P is the deuteration of water W3; D Y is the deuteration degree of the feed of deuterium enriched ammonia A3 from deuterium enriched ammonia A3 storage unit (3300); f is the flow rate of deuterium enriched water W4 discharged from a reboiler (4330), kg/h, D F is the deuteration degree of deuterium enriched water W4; N is the discharge rate of ammonia A2 discharged from the absorption tower (4110), kg/h, D N is the deuteration degree of ammonia A2; M0 is the relative molecular mass of NH 3 and M1 is the relative molecular mass of H 2 O.
  20. 20. The method for producing deuterium-enriched water by combining chemical exchange and liquid ammonia rectification according to any one of claims 11-14 and 16-17, wherein (3) water ammonia exchange further comprises any one or more of the following conditions (I) - (V): (I) The decomposing tower gas generated by high-temperature decomposition in the decomposing tower (4320) is condensed and then is introduced into the exchanging tower (4210) from the bottom of the exchanging tower (4210); (II) introducing the decomposing tower treatment liquid into a reboiler (4330) for discharging, and then performing condensation treatment to obtain deuterium-enriched water W4 as a final product; (III) the feeding mole ratio of deuterium enriched ammonia A3 product extracted by the rectifying tower (3110) to water W3 is 1 (1.5-2.0); (IV) the temperature range in the absorption tower (4110) is-10-30 ℃, the liquid inlet temperature of the absorption tower treatment liquid into the exchange tower (4210) is 10-20 ℃, and the temperature range in the exchange tower (4210) is 0-80 ℃; The temperature of the inlet liquid of the treatment liquid of the exchange tower into the decomposition tower (4320) is 50-80 ℃, and the temperature range in the decomposition tower (4320) is 110-150 ℃.

Description

System and process for producing deuterium-enriched water by combining chemical exchange and liquid ammonia rectification Technical Field The invention belongs to the technical field of hydrogen isotope enrichment, and particularly relates to a system and a process for producing deuterium-enriched water by combining chemical exchange and liquid ammonia rectification. Background The hydrogen isotopes include three nuclides of protium (1H), deuterium (2H or D) and tritium (3H or T), protium and deuterium are stable hydrogen isotopes, and tritium is radioactive. The hydrogen isotope exists in oxides of different forms, including H 2O、HDO、D2O、HTO、DTO、T2 O in six forms. The separation process of the hydrogen isotope oxide has extremely important roles in the fields of civil use, nuclear power, fusion energy, military industry and the like. The separation method of the hydrogen isotope oxide mainly includes a chemical exchange method, a rectification method, an electrolysis method, a chromatographic separation method, a thermal diffusion method, a membrane diffusion adsorption method, a centrifugation method, a laser method, and the like. However, as a method for industrial production, methods having a large-scale use value mainly include a chemical exchange method, an electrolytic method and a rectification method. The chemical exchange method realizes separation based on different distribution coefficients of hydrogen isotope oxide in each phase under different temperature conditions, such as a water-hydrogen double-temperature exchange method, but the method involves multi-tower temperature change control, is complex in operation, has high equipment investment cost, and involves a corrosive hydrogen carrier such as hydrogen sulfide. The combination of catalytic exchange and electrolysis can obviously improve the separation efficiency, but the process uses a large amount of noble metal catalyst, has limited energy production and extremely high electricity consumption investment. The rectification method utilizes the difference of vapor pressures of different components to realize the separation purpose, and the method has the advantages of small fixed investment, low operation and maintenance cost and the like, and can realize large-scale treatment by adding balance stages or cascade operation and the like, and meanwhile, the method is simple and reliable to operate, has no pollution in the production process, and has the advantages of small fixed investment, low operation and maintenance cost and the like. With the continuous development of the technology of hydrogen isotope oxide, the chemical exchange-rectification combined process is developed gradually, but the problems of low energy utilization rate, low deuterium resource recovery rate, poor raw material adaptability, high-pressure high-temperature operation cost and the like still exist. For example, the patent publication No. CN115215498B discloses a device and a method for treating hydrogen isotope wastewater and recycling and application, wherein the device comprises an exchange unit for performing hydrogen isotope exchange on gas-liquid two phases to obtain heavy hydrogen ammonia and low heavy hydrogen saturated ammonia, a rectification unit for separating the heavy hydrogen ammonia from the exchange unit to obtain low heavy hydrogen ammonia and heavy hydrogen liquid ammonia, and separating the low heavy hydrogen saturated ammonia from the exchange unit to obtain water with the heavy hydrogen content reaching the standard, and a decomposition unit for separating the liquid ammonia from the rectification unit to obtain heavy hydrogen and nitrogen. The rectification unit relies on a traditional tower top condenser and a tower kettle reboiler, the cold and heat source separation supply leads to low energy utilization rate, the gas phase ammonia at the top of the rectification tower needs to be additionally condensed and liquefied, the latent heat of light component steam is not utilized, low-temperature heat waste is caused, the production cost is increased, the anhydrous ammonia exchange unit is adopted in the method, the heavy hydrogen liquid ammonia separated by liquid ammonia rectification is not recycled by reverse deuterium, and is converted into heavy water, but enters the decomposition unit to be destructively treated, a high-purity heavy water product cannot be obtained, and high-value deuterium resources are scattered in a gas form. The prior art (Li Zhen et al, ammonia-water deuterium exchange method for purifying nuclear reactor heavy water [ J ]. Nuclear science and engineering, 2004, 24 (1): 24-26.) reports the purification of nuclear reactor heavy water by a process flow combining an ammonia-water deuterium exchange method with an ammonia rectification method, light gas phase ammonia (ND 2H、NDH2、NH3) and raw material liquid phase heavy water in an exchange column 2 at 0.3MPa (absolute pressure), Deuterium exchange at 80 deg.c to prod