Energy-saving hydrogen isotope oxide separation device
By introducing an energy-saving unit into the hydrogen isotope oxide separation device, the low-temperature heat source at the top of the tower is converted into a high-temperature heat source, and the waste heat of steam is recycled, the problem of high energy consumption in the existing process is solved, and the overall energy consumption is reduced. It is suitable for fields such as deuterium-depleted water production and heavy water upgrading.
Patent Information
- Application Number
- CN202422004849.8
- Authority / Receiving Office
- CN · China
- Patent Type
- Utility models(China)
- Current Assignee / Owner
- Filing Date
- 2024-08-19
- Publication Date
- 2025-09-16
- Estimated Expiration
- 2034-08-19
AI Technical Summary
The existing hydrogen isotope oxide separation process has high energy consumption. How to reduce the energy consumption in the separation process to improve the economic efficiency of engineering applications.
By introducing energy-saving units, the low-temperature heat source at the top of the tower is converted into a usable high-temperature heat source, the waste heat of the steam at the top of the tower is recycled, and the direct and indirect conversion structures are combined to reduce process energy consumption.
The method achieves reduced energy consumption in the hydrogen isotope oxide separation process and is suitable for hydrogen isotope oxide separation devices, especially for applications in deuterium-depleted water production, heavy water upgrading and nuclear power.
Smart Images
Figure CN223337130U_ABST
Abstract
Description
Technical Field
[0001] The utility model relates to the technical field of separation and energy saving, and in particular to an energy-saving hydrogen isotope oxide separation device. Background Art
[0002] In nature, hydrogen 1 H (hydrogen, H), 2 H (deuterium, D), 3 H (tritium, T) exists in the form of three isotopes, with relative abundances of approximately 99.9844%, 0.0156%, and less than 0.001%, respectively. Tritium is radioactive with a half-life of 12.5 years. When it decays, it emits beta rays to form helium with a mass number of 3.
[0003] The separation of hydrogen isotope oxides involves the production and upgrading of heavy water, the preparation of deuterium-depleted water, the extraction of tritium from heavy water, and the removal / extraction of tritium from water in nuclear power and fusion reactors.
[0004] At present, conventional hydrogen isotope oxide distillation devices and methods are as follows Figure 1 As shown, the separation of hydrogen isotope oxides occurs within a distillation column, equipped with an evaporator / reboiler at the bottom and a condenser at the top. The column is filled with trays or packing. The reboiler evaporates the liquid, causing it to rise along the column. The condenser at the top uses the cooling medium of a heat exchanger to condense the rising vapor, which then flows down the column. The sieve plates or packing within the column provide ample gas-liquid contact surface for heat and mass transfer. The higher-temperature vapor transfers heat to the lower-temperature liquid when it contacts the liquid, condensing the higher-boiling-point components in the vapor phase into liquid. The lower-boiling-point components in the liquid evaporate into gas as a result of the heat. (Hydrogen isotope oxides include H2O, HDO, D2O, HTO, DTO, and T2O, each with varying boiling points and saturated vapor pressures.) The vapor and liquid phases approach equilibrium as they leave each tray or packing level. When the liquid and gas phases of a mixture reach equilibrium, the high-boiling-point component tends to concentrate in the liquid phase, while the low-boiling-point component tends to concentrate in the gas phase. Ultimately, a high-purity gas of the low-boiling-point component can be obtained at the top of the tower, while a high-purity liquid of the high-boiling-point component can be obtained at the bottom of the tower.
[0005] The hydrogen isotope oxide separation process involves no catalytic exchange between water and hydrogen molecules, eliminating the risk of hydrogen explosion. The device is simple, robust, and easy to operate, offering advantages such as ease of scale-up and a wide range of processing capacity. However, due to the need for continuous heating and condensing of the isotope oxides, the process is energy-intensive. Reducing energy consumption during the separation process is crucial for its engineering applications. Utility Model Content
[0006] In response to the problem of huge process energy consumption in the above-mentioned existing technologies, the utility model provides an energy-saving hydrogen isotope oxide separation device. By introducing an energy-saving unit, the low-temperature heat source at the top of the tower is converted into a usable high-temperature heat source, and the waste heat of the steam at the top of the tower is reused, so as to reduce the overall energy consumption of the process.
[0007] In order to achieve the above purpose, the technical solution adopted by the present utility model is as follows:
[0008] An energy-saving hydrogen isotope oxide separation device comprises a raw water tank, a water distillation tower, an energy-saving unit, a reboiler, a depleted water storage tank and an enriched water storage tank connected by pipelines. The raw water tank is used to contain raw water to be separated and input the raw water into the water distillation tower. The water distillation tower is used to output high-purity gas with low boiling point components from the top of the tower and high-purity liquid with high boiling point components from the bottom of the tower after separation of the raw water. The energy-saving unit is used to directly or indirectly convert the low-temperature heat source of the gas output from the top of the tower into a usable high-temperature heat source through a compressor and supply it to the reboiler arranged at the bottom of the tower, thereby realizing the recycling of waste heat from the steam at the top of the tower. The reboiler is used to evaporate the liquid output from the bottom of the tower after receiving the high-temperature heat source. The depleted water storage tank is used to collect depleted water formed by the gas output from the top of the tower, and the enriched water storage tank is used to collect enriched water formed by the liquid output from the bottom of the tower.
[0009] Specifically, the raw water to be separated contained in the raw water tank is a hydrogen isotope oxide composed of any combination and any concentration of H2O, HDO, D2O, HTO, DTO, and T2O.
[0010] Specifically, the water distillation tower is provided with separation sieve plates or filled with separation packing. The separation sieve plates or separation packing provide sufficient gas-liquid contact surface for heat and mass transfer: when the higher temperature steam contacts the lower temperature liquid, heat is transferred to the liquid, while the high-boiling point component gas in the gas phase is condensed into liquid; the low-boiling point component in the liquid is evaporated into gas by heat. The steam and liquid leaving each sieve plate or each level of packing are more inclined to equilibrium. When the liquid and gas phases of the mixture reach phase equilibrium, the high-boiling point component tends to concentrate in the liquid phase, while the low-boiling point component tends to concentrate in the gas phase. Ultimately, high-purity low-boiling point component gas can be obtained at the top of the tower, and high-purity high-boiling point component liquid can be obtained at the bottom of the tower.
[0011] Specifically, the reboiler is a vertical heat exchanger, which can be a high-efficiency coil heat exchanger or shell-and-tube heat exchanger. The liquid output from the bottom of the tower is connected through the tube side, and the high-temperature heat source is connected through the shell side. The flow rate can be adjusted according to the required heat.
[0012] Specifically, the output flow of the raw water tank is the sum of the input flow of the depleted water storage tank and the enriched water storage tank to ensure material balance.
[0013] Specifically, the present invention provides two design solutions for the energy-saving unit: a direct conversion structure and an indirect conversion structure:
[0014] First, the energy-saving unit adopts a direct conversion structure, including a compressor, the input end of the compressor receives the gas output from the top of the water distillation tower, and the output end is connected to the shell-side input port of the reboiler. The shell-side output port of the reboiler inputs a part of the heat-exchanged liquid into the depleted water storage tank through a reflux pipeline and inputs another part of the heat-exchanged liquid into the reflux port of the water distillation tower. A water pump is configured on the reflux pipeline.
[0015] In addition, the top output port of the water distillation tower is also connected to a vacuum pump.
[0016] Secondly, the energy-saving unit adopts an indirect conversion structure, including a top heat exchanger, a compressor and an expansion valve. The top heat exchanger adopts a refrigerant to absorb the heat of the top output gas of the water distillation tower, and its pipe-side input port is connected to the top output port of the water distillation tower. The pipe-side output port inputs a part of the heat-exchanged liquid into the depleted water storage tank and inputs another part of the heat-exchanged liquid into the reflux port of the water distillation tower. The input end of the compressor is connected to the shell-side output port of the top heat exchanger, and the output end is connected to the shell-side input port of the reboiler. The shell-side output port of the reboiler is connected to the shell-side input port of the top heat exchanger through the refrigerant return pipeline, and the expansion valve is arranged on the refrigerant return pipeline.
[0017] In addition, the tube side of the tower top heat exchanger is also connected to a vacuum pump.
[0018] Compared with the prior art, the present invention has the following beneficial effects:
[0019] (1) This utility model couples a compressor-based energy-saving unit to a traditional distillation process, realizing the recycling of waste heat from the tower top steam, thereby achieving energy conservation and reducing the energy consumption of the overall process. This utility model has an ingenious design, is easy to use, and has good technical effects, and is suitable for application in the separation of hydrogen isotope oxides.
[0020] (2) The utility model adopts two design schemes of direct and indirect conversion structures to achieve the effect of recycling the waste heat of the tower top steam. One is to directly compress the tower top steam through a compressor into a high-pressure and high-temperature state, and then the high-temperature and high-pressure steam exchanges heat with the liquid hydrogen isotope oxide at the bottom of the tower in the reboiler at the bottom of the tower to evaporate it. The other is to use a low-pressure and low-temperature refrigerant to absorb the heat of the high-temperature steam at the top of the tower in the heat exchanger at the top of the tower. The refrigerant absorbs heat and becomes gaseous, and then is compressed by a compressor to become high-temperature and high-pressure. The high-temperature and high-pressure refrigerant heats the liquid hydrogen isotope oxide at the bottom of the tower in the reboiler at the top of the tower and becomes a low-temperature and high-pressure state. Finally, it is changed to a low-temperature and low-pressure state through expansion throttling and enters the heat exchanger at the top of the tower to start a new cycle process. BRIEF DESCRIPTION OF THE DRAWINGS
[0021] Figure 1 This is a schematic diagram of the structure of a device for separating hydrogen isotope oxides using an existing distillation process.
[0022] Figure 2 It is a schematic diagram of the overall structure of the utility model.
[0023] Figure 3 This is a schematic structural diagram of Example 1 of the present utility model.
[0024] Figure 4 This is a schematic structural diagram of Example 2 of the present utility model. DETAILED DESCRIPTION
[0025] The present invention will be further described below with reference to the accompanying drawings and examples. The implementation methods of the present invention include but are not limited to the following examples.
[0026] Example 1
[0027] like Figure 2 and Figure 3 As shown, the energy-saving hydrogen isotope oxide separation device is mainly used for deuterium-depleted water production and heavy water upgrading, including a raw water tank, a water distillation tower, a compressor, a reboiler, a depleted water storage tank, an enriched water storage tank, a water pump and a vacuum pump.
[0028] The raw water tank holds the raw water to be separated and feeds it into the water distillation column. The raw water, purified by an RO water purifier, consists primarily of H2O, containing a naturally occurring deuterium concentration of 0.015%. The raw water enters the water distillation column at a flow rate of 40 kg / h. It is heated in the reboiler, converted into steam, and flows upward. Heat and mass transfer occur between the packing within the water distillation column and the descending liquid water. The higher-temperature steam transfers heat to the liquid as it contacts the cooler liquid, condensing the high-boiling-point gas HDO in the vapor phase into liquid. The lower-boiling-point H2O in the liquid evaporates as heat. The vapor and liquid phases of the mixture approach equilibrium as they leave each tray or packing level. When the liquid and vapor phases of the mixture reach equilibrium, the higher-boiling-point HDO tends to concentrate in the liquid phase, while the lower-boiling-point H2O tends to concentrate in the vapor phase. Ultimately, high-purity H2O gas (a low-boiling-point component) is obtained at the top of the tower, while high-purity HDO liquid (a high-boiling-point component) is obtained at the bottom. This process produces 26 kg / h of enriched water with a deuterium concentration of 209 ppm at the bottom of the tower, and 14 kg / h of depleted water with a deuterium concentration of 40.4 ppm at the top of the tower.
[0029] The pressure inside the water distillation tower is regulated by a vacuum pump. The pressure and temperature at the top of the tower are 12.4 kPa (absolute pressure) and 50°C respectively. It is directly compressed by a compressor to produce water vapor at 65°C, which is used to heat the bottom water at the reboiler at the bottom of the tower. The water condensed after heat exchange in the reboiler is refluxed to the top of the tower through a water pump. The pressure and temperature of the water at the bottom of the tower are 14.8 kPa (absolute pressure) and 54°C respectively.
[0030] By adjusting the extraction flow rate, deuterium-depleted water of varying concentrations can be obtained and collected in the depleted water storage tank. The enriched water is continuously concentrated through a multi-stage cascade of water distillation towers to produce high-concentration heavy water, which is collected in the enriched water storage tank.
[0031] Example 2
[0032] like Figure 2 and Figure 4 As shown, the energy-saving hydrogen isotope oxide separation device is mainly used for removing / extracting tritium from water, including a raw water tank, a water distillation tower, a tower top heat exchanger, a compressor, a reboiler, an expansion valve, a depleted water storage tank, an enriched water storage tank and a vacuum pump.
[0033] The raw water is tritium-containing wastewater produced in fusion reactors or tritium-related processes, mainly H2O, with a tritium concentration of 10 2 Bq / L~10 8 Bq / L (1×10 5 Bq / L, for example, enters a water distillation tower at a flow rate of 10 kg / h. It is heated in the reboiler and converted into steam, which rises upward. Heat and mass transfer occur between the packing inside the water distillation tower and the descending liquid water. When the higher-temperature steam contacts the lower-temperature liquid, it transfers heat to the liquid, simultaneously condensing the high-boiling-point gas H2O in the gas phase into liquid. The lower-boiling-point H2O in the liquid evaporates into gas due to the heat. The vapor and liquid phases of the mixture approach equilibrium with each tray or packing level. When the liquid and gas phases of the mixture reach equilibrium, the higher-boiling-point H2O tends to concentrate in the liquid phase, while the lower-boiling-point H2O tends to concentrate in the gas phase. Ultimately, high-purity H2O gas, the lower-boiling-point component, is obtained at the top of the tower, while high-purity H2O liquid, the higher-boiling-point component, is obtained at the bottom. Through this process, 2 kg / h of tritium with a concentration of 4.9×10 5 Bq / L of enriched water, 8 kg / h of tritium with a concentration of 2.5×10 3 Bq / L of depleted water.
[0034] The pressure inside the water distillation tower is regulated by a vacuum pump. The water vapor pressure and temperature at the top of the tower are 12.4 kPa (absolute pressure) and 50°C, respectively. By introducing a refrigerant, a low-pressure, low-temperature refrigerant is used to absorb the heat of the water vapor at the top of the tower in the heat exchanger at the top of the tower, and the condensed water generated by the heat exchange flows back to the top of the distillation tower; the refrigerant absorbs heat and becomes gaseous, and is compressed by a compressor to become high temperature (80°C) and high pressure. The high-temperature, high-pressure refrigerant heats the liquid hydrogen isotope oxide at the bottom of the tower in the reboiler at the bottom of the tower and becomes a low-temperature, high-pressure state. It is throttled by the expansion valve to become low-temperature, low-pressure, and then enters the heat exchanger at the top of the tower to start a new cycle; the water pressure and temperature at the bottom of the tower are 25 kPa (absolute pressure) and 65°C, respectively.
[0035] By adjusting the extraction flow rate, tritium-depleted water of varying concentrations can be obtained and collected in a depleted water storage tank. Depleted water is continuously depleted through a multi-stage cascade of water distillation towers, reducing it to below 10 Bq / L. Enriched water is collected at the bottom of the tower in an enriched water storage tank.
[0036] The above embodiments are only preferred embodiments of the present invention and are not intended to limit the scope of protection of the present invention. Any changes based on the design principles of the present invention and any changes made through non-creative work on this basis shall fall within the scope of protection of the present invention.
Claims
1. An energy-saving hydrogen isotope oxide separation device, characterized in that: It includes a raw water tank, a water distillation tower, an energy-saving unit, a reboiler, a depleted water storage tank and an enriched water storage tank connected by pipelines. The raw water tank is used to contain the raw water to be separated and input the raw water into the water distillation tower. The water distillation tower is used to output high-purity gas with low boiling point components from the top of the tower after separation of the raw water, and output high-purity liquid with high boiling point components from the bottom of the tower. The energy-saving unit is used to directly or indirectly convert the low-temperature heat source of the gas output from the top of the tower into a usable high-temperature heat source through a compressor and supply it to the reboiler arranged at the bottom of the tower, so as to realize the recycling of waste heat of the steam at the top of the tower. The reboiler is used to evaporate the liquid output from the bottom of the tower after receiving the high-temperature heat source. The depleted water storage tank is used to collect the depleted water formed by the gas output from the top of the tower, and the enriched water storage tank is used to collect the enriched water formed by the liquid output from the bottom of the tower.
2. The energy-saving hydrogen isotope oxide separation device according to claim 1, characterized in that: The raw water to be separated contained in the raw water tank is a hydrogen isotope oxide composed of any combination and any concentration of H2O, HDO, D2O, HTO, DTO, and T2O.
3. The energy-saving hydrogen isotope oxide separation device according to claim 1, characterized in that: The water distillation tower is provided with a separation sieve plate or filled with a separation filler.
4. The energy-saving hydrogen isotope oxide separation device according to claim 1, characterized in that: The reboiler adopts a coil heat exchanger or a shell and tube heat exchanger, the liquid output from the bottom of the tower is connected through the tube side, and the high-temperature heat source is connected through the shell side.
5. The energy-saving hydrogen isotope oxide separation device according to claim 1, characterized in that: The output flow rate of the raw water tank is the sum of the input flow rates of the depleted water storage tank and the enriched water storage tank.
6. The energy-saving hydrogen isotope oxide separation device according to any one of claims 1 to 5, characterized in that: The energy-saving unit adopts a direct conversion structure, including a compressor, the input end of the compressor receives the gas output from the top of the water distillation tower, and the output end is connected to the shell-side input port of the reboiler. The shell-side output port of the reboiler inputs a portion of the heat-exchanged liquid into the depleted water storage tank through a reflux pipeline and inputs another portion of the heat-exchanged liquid into the reflux port of the water distillation tower. A water pump is configured on the reflux pipeline.
7. The energy-saving hydrogen isotope oxide separation device according to claim 6, characterized in that: The top output port of the water rectification tower is also connected to a vacuum pump.
8. The energy-saving hydrogen isotope oxide separation device according to any one of claims 1 to 5, characterized in that: The energy-saving unit adopts an indirect conversion structure, including a tower top heat exchanger, a compressor and an expansion valve. The tower top heat exchanger uses a refrigerant to absorb the heat of the tower top output gas of the water distillation tower. The tube side input port is connected to the tower top output port of the water distillation tower. The tube side output port inputs a portion of the heat-exchanged liquid into the depleted water storage tank and inputs another portion of the heat-exchanged liquid into the reflux port of the water distillation tower. The input end of the compressor is connected to the shell side output port of the tower top heat exchanger, and the output end is connected to the shell side input port of the reboiler. The shell side output port of the reboiler is connected to the shell side input port of the tower top heat exchanger through a refrigerant return pipeline. The expansion valve is arranged on the refrigerant return pipeline.
9. The energy-saving hydrogen isotope oxide separation device according to claim 8, characterized in that: The tube side of the tower top heat exchanger is also connected to a vacuum pump.