Cryogenic distillation apparatus for deuterium separation and purification equipped with pre-cooling function and deuterium separation method using the same

Abstract

The present invention relates to a cryogenic distillation apparatus for separating and purifying deuterium equipped with a pre-cooling function and a method for separating deuterium using the same. The present invention provides a cryogenic distillation apparatus for separating and purifying deuterium, comprising: a main body (10); a preheat exchanger (100) formed inside the main body (10); an auxiliary chiller (110) for preheating the preheat exchanger (100); a cooling pipe (120) installed spirally along the outside of the preheat exchanger (100), having an inlet formed at one end through which a mixed gas containing deuterium (D2) and deuterated hydrogen (HD) is injected; and a main heat exchanger (130) coupled to the other end of the cooling pipe (120), into which the mixed gas is introduced from the cooling pipe (120) and cryogenically distilled to separate the deuterium and the deuterated hydrogen. The invention is characterized by having a preheating function. The cryogenic distillation apparatus for separating and purifying deuterium equipped with a pre-cooling function according to the present invention is equipped with a pre-cooling function, making it easy to finely control the temperature in the cryogenic environment where deuterium and deuteriumized hydrogen are separated, and can efficiently remove deuteriumized hydrogen (HD), which is an impurity, from the mixed gas of deuterium and deuteriumized hydrogen to stably obtain high-purity deuterium (D2) while simultaneously improving the purity and recovery rate of deuterium.

Description

Technology Field

[0001] The present invention relates to a cryogenic distillation apparatus for separating and purifying deuterium equipped with a pre-cooling function and a method for separating deuterium using the same. More specifically, the invention relates to a cryogenic distillation apparatus for separating and purifying deuterium equipped with a pre-cooling function that facilitates fine temperature control in a cryogenic environment where deuterium and deuteride hydrogen are separated, and to a method for separating deuterium using the same that efficiently separates impure deuteride hydrogen (HD) from a mixed gas of deuterium and deuteride hydrogen to stably obtain high-purity deuterium (D2) while simultaneously improving the purity and recovery rate of deuterium. Background Technology

[0002] Deuterium (D) is an isotope of hydrogen in which there is one additional neutron in the nucleus of ordinary hydrogen (H), and exists as molecules in the forms of hydrogen (H2), hydrogen deuteride (HD), and deuterium (D2).

[0003] For most elements, an increase of one to three neutrons does not result in a significant change in mass; however, for elements with low mass, such as hydrogen, a change in the number of neutrons causes a relatively large change in mass. Substituting these isotopes into a substance alters the vibrational energy within the molecule, leading to diverse changes in physicochemical properties. Furthermore, changes in mass alter kinetic velocities, which in turn causes changes in diffusion rates and reaction rates. This phenomenon is known as the isotope effect, and it is particularly pronounced in deuterium.

[0004] Furthermore, unlike other isotopes, deuterium is chemically stable and does not undergo nuclear fission; thus, it can achieve greater stability than ordinary hydrogen based on changes in reactivity caused by mass variations. For this reason, there has recently been a trend to prefer deuterium in the electronics and semiconductor industries, and active research is currently underway.

[0005] Meanwhile, various utility gases are used in the semiconductor / LCD device manufacturing process. In particular, semiconductor devices are manufactured by repeatedly performing a series of processes including film deposition, photolithography, etching, impurity implantation, and metallization, and various types of gases are used in the execution of the above series of processes. Among them, deuterium (D2) is used in high-pressure annealing equipment to prevent leakage current caused by tunneling phenomena occurring in processes of 28 nm or less.

[0006] Generally, deuterium (D₂) is produced by electrolyzing heavy water (D₂O), but trace amounts of its isotope, hydrogen deuteride (HD), are present as impurities within the deuterium (D₂) produced during this process. A representative method for purifying this is cryogenic distillation, and methods for purification using porous adsorbents with high selectivity for specific components are also being actively researched.

[0007] However, cryogenic distillation has the disadvantage of high energy consumption to maintain cryogenic temperatures and presented the problem of difficulty in controlling temperature due to minute differences in boiling points in low-temperature environments, while the method utilizing adsorbents had the problem of difficulty in controlling adsorbate selectivity when the physical and chemical properties of each component of the mixture were similar.

[0008] Since deuterium is used in fine semiconductor processes, a decrease in its purity can reduce the efficiency of the isotope effect, thereby affecting quality and performance. Therefore, it is necessary to efficiently remove hydrogen deuteride, an impurity, to obtain high-purity deuterium, and there is a need to improve the purity and recovery rate of deuterium from an economic perspective.

[0009] In order to meet the above requirements, there is a need for research on deuterium separation and purification technology capable of obtaining high-purity deuterium with improved purity and recovery rates by removing hydrogen deutride, an impurity, as much as possible. Prior art literature

[0010] Korean Registered Patent No. 10-2095274 (March 25, 2020) Korean Registered Patent No. 10-1425650 (July 25, 2014) The problem to be solved

[0011] The present invention was devised to solve the problems of the prior art as described above, and aims to provide technical details regarding a cryogenic distillation apparatus for deuterium separation and purification equipped with a pre-cooling function, which facilitates fine temperature control in a cryogenic environment where deuterium and deuteride hydrogen are separated, and which can stably obtain high-purity deuterium (D2) by efficiently removing impure deuteride hydrogen (HD) from a mixed gas of deuterium and deuteride hydrogen, while simultaneously improving the purity and recovery rate of deuterium, and a method for separating deuterium using the same. means of solving the problem

[0012] The present invention relates to a cryogenic distillation apparatus for separating and purifying deuterium equipped with a pre-cooling function and a method for separating deuterium using the same.

[0013] To achieve the technical objectives described above, the present invention provides a cryogenic distillation apparatus for separating and purifying deuterium equipped with a pre-cooling function, comprising: a main body (10); a pre-heat exchanger (100) formed inside the main body (10); an auxiliary chiller (110) for pre-cooling the pre-heat exchanger (100); a cooling pipe (120) installed spirally along the outside of the pre-heat exchanger (100), having an inlet formed at one end, through which a mixed gas containing deuterium (D2) and deuterated hydrogen (HD) is injected; and a main heat exchanger (130) coupled to the other end of the cooling pipe (120), into which the mixed gas flows from the cooling pipe (120), and which separates the deuterium and the deuterated hydrogen by cryogenic distillation of the mixed gas.

[0014] According to a preferred embodiment of the present invention, the invention may further include an auxiliary heat exchanger (150) into which deuterium hydrogen gas separated from the main heat exchanger (130) is injected, and may be characterized by having an activated carbon filter (151) that selectively adsorbs only the deuterium hydrogen inside the auxiliary heat exchanger (150).

[0015] In addition, according to a preferred embodiment of the present invention, the main refrigerator (140) for cooling the main heat exchanger (130) to a predetermined target temperature may be further included, and the heating film and demister filter may be provided inside the main heat exchanger (130).

[0016] In addition, according to a preferred embodiment of the present invention, the device may further include a protective case (11) formed inside the main body (10), and the device may be characterized in that the preheat exchanger (100), main heat exchanger (130), and auxiliary heat exchanger (150) are installed inside the protective case (11).

[0017] In addition, according to a preferred embodiment of the present invention, the target temperature may be characterized by separation taking place at a temperature of 20 to 25 K.

[0018] And, according to a preferred embodiment of the present invention, a method for separating deuterium using a cryogenic distillation apparatus for separating and purifying deuterium equipped with a pre-cooling function may include: (a) a step of pre-cooling a deuterium-deuterium mixed gas injected through an inlet at one end of a cooling pipe (120) provided in the cryogenic distillation apparatus for separating and purifying deuterium to a temperature of 10 to 20 K; (b) a step of introducing the pre-cooled mixed gas into a main heat exchanger (130) and raising the temperature to 20 to 25 K to separate and remove the deuterium, which is an impurity; and (c) a step of raising the temperature of the high-purity liquid deuterium from which the deuterium has been removed to 25 to 100 K to obtain high-purity gaseous deuterium. Effects of the invention

[0019] The present invention relates to a cryogenic distillation apparatus for separating and purifying deuterium equipped with a pre-cooling function and a method for separating deuterium using the same.

[0020] To achieve the technical objectives described above, the present invention provides a cryogenic distillation apparatus for separating and purifying deuterium equipped with a pre-cooling function, comprising: a main body (10); a pre-heat exchanger (100) formed inside the main body (10); an auxiliary chiller (110) for pre-cooling the pre-heat exchanger (100); a cooling pipe (120) installed spirally along the outside of the pre-heat exchanger (100), having an inlet formed at one end, through which a mixed gas containing deuterium (D2) and deuterated hydrogen (HD) is injected; and a main heat exchanger (130) coupled to the other end of the cooling pipe (120), into which the mixed gas flows from the cooling pipe (120), and which separates the deuterium and the deuterated hydrogen by cryogenic distillation of the mixed gas.

[0021] According to a preferred embodiment of the present invention, the invention may further include an auxiliary heat exchanger (150) into which deuterium hydrogen gas separated from the main heat exchanger (130) is injected, and may be characterized by having an activated carbon filter (151) that selectively adsorbs only the deuterium hydrogen inside the auxiliary heat exchanger (150).

[0022] In addition, according to a preferred embodiment of the present invention, the main refrigerator (140) for cooling the main heat exchanger (130) to a predetermined target temperature may be further included, and the heating film and demister filter may be provided inside the main heat exchanger (130).

[0023] In addition, according to a preferred embodiment of the present invention, the device may further include a protective case (11) formed inside the main body (10), and the device may be characterized in that the preheat exchanger (100), main heat exchanger (130), and auxiliary heat exchanger (150) are installed inside the protective case (11).

[0024] In addition, according to a preferred embodiment of the present invention, the target temperature may be characterized by separation taking place at a temperature of 20 to 25 K.

[0025] And, according to a preferred embodiment of the present invention, a method for separating deuterium using a cryogenic distillation apparatus for separating and purifying deuterium equipped with a pre-cooling function may include: (a) a step of pre-cooling a deuterium-deuterium mixed gas injected through an inlet at one end of a cooling pipe (120) provided in the cryogenic distillation apparatus for separating and purifying deuterium to a temperature of 10 to 20 K; (b) a step of introducing the pre-cooled mixed gas into a main heat exchanger (130) and raising the temperature to 20 to 25 K to separate and remove the deuterium, which is an impurity; and (c) a step of raising the temperature of the high-purity liquid deuterium from which the deuterium has been removed to 25 to 100 K to obtain high-purity gaseous deuterium. Brief explanation of the drawing

[0026] FIG. 1 is a drawing for explaining a cryogenic distillation apparatus for separating and purifying deuterium equipped with a pre-cooling function according to an embodiment of the present invention and a method for separating deuterium using the same. FIG. 2 is a flowchart illustrating a cryogenic distillation apparatus for separating and purifying deuterium equipped with a pre-cooling function according to an embodiment of the present invention and a method for separating deuterium using the same. FIG. 3 is a diagram showing the gas chromatography (GC) results after deuterium separation and purification according to an embodiment of the present invention. Specific details for implementing the invention

[0027] Hereinafter, a cryogenic distillation apparatus for separating and purifying deuterium equipped with a pre-cooling function according to the present invention and a method for separating deuterium using the same will be described in more detail with reference to specific examples. However, the embodiments introduced below are provided as examples to ensure that the concept of the present invention is sufficiently conveyed to those skilled in the art.

[0028] Accordingly, the present invention is not limited to the embodiments presented below and may be embodied in other forms, and the embodiments presented below are described merely to clarify the concept of the present invention and are not limited thereto.

[0029] Unless otherwise defined, technical and scientific terms used herein have the meanings commonly understood by those skilled in the art to which this invention pertains, and are defined in consideration of their functions in the present invention; such definitions may vary depending on the intent or convention of the user or operator. Therefore, the definitions of these terms should be based on the content throughout this specification, and descriptions of known functions and configurations that could unnecessarily obscure the essence of the present invention are omitted in the following description.

[0030] Additionally, the singular form used in the specification and attached claims may be intended to include the plural form unless specifically indicated otherwise in the context.

[0031] In addition, the thickness of lines or the size of components shown in the drawings may be exaggerated for clarity and convenience of explanation.

[0032] In addition, in the present invention, heavy water (D2O) refers to two deuterium atoms (D) with a mass number of 2 combined with one oxygen atom (O), and deuterium hydrogen (HD) refers to one deuterium atom (D) with a mass number of 2 combined with one light hydrogen atom (H) with a mass number of 1.

[0033] The present invention will be described in detail below.

[0034] The cryogenic distillation apparatus for separating and purifying deuterium equipped with a pre-cooling system according to the present invention and the method for separating deuterium using the same may comprise, in the cryogenic distillation apparatus for separating and purifying deuterium, a main body (10), a pre-heat exchanger (100) formed inside the main body (10), an auxiliary chiller (110) for pre-cooling the pre-heat exchanger (100), a cooling pipe (120) installed spirally along the outside of the pre-heat exchanger (100) and having an inlet formed at one end, through which a mixed gas containing deuterium (D2) and deuterated hydrogen (HD) is injected, and a main heat exchanger (130) coupled to the other end of the cooling pipe (120) to receive the mixed gas from the cooling pipe (120) and to separate the deuterium and the deuterated hydrogen by cryogenic distillation of the mixed gas.

[0035] The above deuterium (D2) is an isotope of hydrogen and is in the molecular form of a deuterium atom (D). Hydrogen (light hydrogen; 1 The atom H (Hydrogen) has two relatively stable isotopes, one of which is deuterium ( 2 H(D), Deuterium) and another one is tritium ( 3 H(T), Tritium. While the nucleus of the above hydrogen (H) consists of one proton, the nucleus of deuterium (D) consists of one proton and one neutron. Due to this composition, the atomic weight of deuterium is approximately twice that of a hydrogen atom (1.007947 Da) (2.014102 Da). Additionally, the above deuterium accounts for about 0.0145% of the natural environment, and heavy water (D2O), in which the hydrogen of water (H2O) is replaced by deuterium, has a smaller neutron absorption cross-section compared to light water (H2O), so it is used as a reactor moderator, coolant, etc.

[0036] In the present invention, when producing the deuterium (D2), It can also be produced by electrolyzing heavy water (D2O). Additionally, trace amounts of the isotope hydrogen deuteride (HD) may be present within the deuterium (D₂) produced during this process. In this regard, the deuterium mixed gas containing trace amounts of hydrogen deuteride produced by the above electrolysis method can be purified using a cryogenic distillation apparatus for deuterium separation and purification equipped with the pre-cooling system of the present invention. Accordingly, high-purity deuterium can be obtained from the said mixed gas.

[0037] In the present invention, the main body (10) may refer to the entire cryogenic distillation tower for deuterium separation and purification equipped with a pre-cooling system. Additionally, the main body (10) may further include a protective case (11) formed inside, and the pre-heat exchanger (100), main heat exchanger (130), and auxiliary heat exchanger (150) may be installed inside the protective case (11).

[0038] The initial vacuum inside the protective case (11) can be maintained at 0 to 1 Pa. When the vacuum pressure inside the protective case (11) is within the above range, there is no convection because the gas flow is in the free molecular motion region, and the gas phase thermal conductivity is reduced, thereby eliminating the amount of heat transfer by the gas.

[0039] In addition, in the present invention, the protective case (11) is a vacuum insulation cooling box and can maintain a vacuum and insulation state through multilayer insulation (MLI), and the multilayer insulation may be composed of a sandwich structure in which a low-conductivity material called a spacer is inserted between several layers of radiation-reflecting metal films called a shield.

[0040] The above shield may be made of a gold or aluminum-based material with high reflectivity, and the above spacer may be made of low-conductivity glass fiber, silk, or nylon, but is not limited thereto.

[0041] By using a vacuum insulation cooling box as the above protective case (11), it is possible to have excellent thermal insulation properties that prevent cold air leakage to the outside while having an excellent heat insulation effect against heat entering from the outside. In addition, energy efficiency can be increased, and the ability to finely control the temperature of the condenser can be improved, which may have the effect of increasing the yield of high-purity deuterium.

[0042] In addition, the protective case (11) can be cooled to a temperature of 10 to 20K. This allows heat entering from the outside to be effectively blocked, while also improving the temperature control capability of the preheat exchanger (100), thereby improving the process efficiency of the cryogenic distillation apparatus for deuterium separation and purification and the deuterium separation method using the same according to the present invention, and having the effect of increasing the recovery rate and purity of high-purity deuterium.

[0043] In the present invention, the preheat exchanger (100) is formed inside the main body (10) and may be installed in the middle section of the auxiliary refrigerator (110). Accordingly, the preheat exchanger (100) may be preheated by the auxiliary refrigerator (110). The preheating may be characterized by a temperature of 10 to 20K.

[0044] In addition, the above preheat exchanger (100) has the cooling pipe (120) installed on its exterior to preheat the deuterium-deuterium hydrogen mixed gas flowing in through the cooling pipe (120).

[0045] Additionally, the above-mentioned preheat exchanger (100) may be characterized by having grooves at regular intervals along the outside, and the above-mentioned cooling pipe (120) may be installed spirally along the grooves. Due to the above-mentioned structural features, the contact area between the preheat exchanger (100) and the cooling pipe (120) may be increased, and accordingly, the heat exchange efficiency between the preheat exchanger (100) and the cooling pipe (120) may be excellent.

[0046] In the present invention, the auxiliary refrigerator (110) may be a device that cools by exchanging heat. A refrigerant may flow inside the auxiliary refrigerator (110) to promote heat convection and perform a cooling function. The refrigerant may be a cryogenic refrigerant and may be supplied into the auxiliary refrigerator (110) and discharged from the auxiliary refrigerator (110) through a cryogenic refrigerant circulation system. The type of refrigerant may be nitrogen or helium, but is not limited thereto.

[0047] The above auxiliary chiller (110) may have its upper portion installed outside the main body (10), and its middle and lower portions installed inside the main body (10). Additionally, a preheat exchanger (100) may be installed in the middle portion of the auxiliary chiller, and an auxiliary heat exchanger (150) may be installed in the lower portion.

[0048] In this regard, the auxiliary chiller (110) may have the function of pre-cooling the pre-heat exchanger (100) installed in the middle section.

[0049] When pre-cooling the above pre-heat exchanger (100), the upper part may be characterized by having a temperature of 70 to 80K and the lower part by having a temperature of 10 to 20K.

[0050] In addition, the auxiliary chiller (110) can cool the auxiliary heat exchanger (150) installed at the bottom.

[0051] In the present invention, the cooling pipe (120) is installed spirally along the outside of the preheat exchanger (100), and one end forms an inlet, through which a mixed gas containing deuterium and hydrogen deuterated is injected and flows along the pipe, and heat is transferred to the preheat exchanger (100) to be preheated.

[0052] In addition, the structural feature of the cooling tube (120) may be that it is wound spirally along a groove provided on the outside of the heat exchanger, and due to the structural feature, the contact area between the cooling tube (120) and the preheater (100) is increased, so that the heat exchange efficiency and cooling efficiency may be excellent.

[0053] Additionally, pre-cooling of the deuterium-deuterium hydrogen mixed gas may occur in the cooling pipe (120). The pre-cooling may be characterized as a process in which the deuterium-deuterium hydrogen mixed gas injected through an inlet at one end of the cooling pipe (120) is pre-cooled before being introduced into the main heat exchanger (130).

[0054] In addition, the above pre-cooling may be characterized by a temperature of 70 to 80K. When the cooling temperature falls within the above range, the thermal efficiency and thermal stability of cryogenic distillation may be increased, and fine temperature control during the cooling process of cryogenic distillation may be facilitated, thereby improving the selectivity for removing hydrogen deuteride, which is an impurity.

[0055] In the present invention, the main heat exchanger (130) is a location in which one side is connected to the cooling pipe (120) to receive the pre-cooled mixed gas of deuterium and deuterated hydrogen, and to separate and purify the deuterium and deuterated hydrogen by cryogenic distillation.

[0056] The interior of the main heat exchanger (130) may be equipped with a heating film and a demister filter.

[0057] The heating film above can serve to raise the temperature more efficiently during the process of recovering deuterium, and the demister filter above can serve to ensure that the gas is evenly dispersed so that heat exchange can take place efficiently.

[0058] Specifically, the main heat exchanger (130) may include four to five stages of demister filters to effectively remove impurities, such as dust and foreign substances, contained in the deuterium-deuteriumized hydrogen mixed gas flowing into the main heat exchanger (130). In addition, this may have the effect of stably obtaining the high-purity deuterium.

[0059] In addition, a main refrigerator (140) is attached to one side of the main heat exchanger (130) so that the main heat exchanger (130) can be cooled to a predetermined target temperature.

[0060] The above target temperature may be a temperature at which hydrogen deuterated, an impurity, is removed in a gaseous state through cryogenic distillation. Specifically, the above target temperature may include the characteristic that separation occurs at a temperature of 20 to 25 K. When the target temperature falls within the above range, hydrogen deuterated can be effectively separated to improve the recovery rate of high-purity deuterium. If the above target temperature is below 20 K, the vaporization of hydrogen deuterated does not occur, so the effect of improving the purity of high-purity deuterium may be insufficient, and if it exceeds 25 K, the vaporization of hydrogen deuterated and deuterium occurs simultaneously, which may lower the recovery rate of high-purity deuterium.

[0061] In the present invention, the main refrigerator (140) may be characterized by having an upper portion installed outside the main body (10) and a lower portion installed inside the main body (10). Additionally, the main heat exchanger (130) may be characterized by being installed below the main refrigerator (140).

[0062] Additionally, the main refrigerator (140) can cool the main heat exchanger (130) to a predetermined target temperature, and the target temperature may be 20 to 25K.

[0063] In the present invention, the auxiliary heat exchanger (150) may be a location where deuterium hydrogen gas separated from the main heat exchanger (130) is introduced. Additionally, an activated carbon filter (151) that adsorbs the deuterium hydrogen may be provided inside the auxiliary heat exchanger (150) to adsorb the deuterium hydrogen introduced from the main heat exchanger (130).

[0064] The activated carbon filter (151) can selectively adsorb only the deuterium hydrogen. Specifically, the activated carbon filter (151) may include surface-modified activated carbon. The surface-modified activated carbon may have functional groups introduced to its surface and increased porosity, thereby having excellent adsorption selectivity for deuterium hydrogen.

[0065] In the surface modification step of the surface-modified activated carbon described above, carbon surface treatment methods such as acid treatment, ozone treatment, and plasma treatment may be utilized, and preferably, an ozone treatment method may be utilized. Through the ozone treatment method, the carbon surface is oxidized, increasing surface roughness and surface oxygen content, which can improve the adsorption capacity for hydrogen deuteride.

[0066] In addition, the remaining deuterium hydrogen after adsorption can be discharged through a pipe connected to a part of the auxiliary heat exchanger (150).

[0067] The auxiliary heat exchanger (150) is installed at the bottom of the auxiliary refrigerator (110) and can be cooled to a temperature of 10 to 20 K by the auxiliary refrigerator (110). Through this, the deuterated hydrogen gas introduced into the auxiliary heat exchanger (150) may be liquefied.

[0068] In the present invention, the pump (160) may be a vacuum pump that reduces internal pressure by being coupled to an inlet formed at one end of a cooling pipe (120), an auxiliary heat exchanger (150), and a part of a main heat exchanger (130).

[0069] In addition, a method for separating deuterium using a cryogenic distillation apparatus for separating and purifying deuterium equipped with the above-mentioned pre-cooling function may include: (a) a step of pre-cooling a deuterium-deuterium mixed gas injected through an inlet at one end of a cooling pipe (120) provided in the cryogenic distillation apparatus for separating and purifying deuterium to a temperature of 70 to 80 K; (b) a step of introducing the pre-cooled mixed gas into a main heat exchanger (130) and raising the temperature to 20 to 25 K to separate and remove the deuterium, which is an impurity; and (c) a step of raising the temperature of the high-purity liquid deuterium from which the deuterium has been removed to 25 to 100 K to obtain high-purity gaseous deuterium.

[0070] The step of pre-cooling the deuterium-deuterium hydrogen mixed gas injected through an inlet at one end of a cooling tube (120) provided in the above (a) cryogenic distillation apparatus for deuterium separation and purification to a temperature of 70 to 80 K; may occur in the cooling tube (120), and the deuterium-deuterium hydrogen mixed gas at 10 to 20 K that has undergone the pre-cooling may exist in a gaseous state.

[0071] (b) the step of introducing the pre-cooled mixed gas into a main heat exchanger (130) and cooling it to a temperature of 20 to 25 K to separate and remove the impurity, the deuterium hydrogen; may be characterized by including a process of increasing the temperature of the condensed mixed gas to 20 to 25 K to vaporize and separate and remove only the impurity, the deuterium hydrogen. Preferably, the condensed mixed gas may be cooled to a temperature of 22 K. By cooling the mixed gas to 22 K, the selectivity of vaporizing the impurity, the deuterium hydrogen, can be improved, and the yield of high-purity deuterium can be increased.

[0072] Additionally, the above step (b) may be characterized by being performed inside the main heat exchanger (130). At this time, a heating film and a demister filter may be provided inside the main heat exchanger (130). By providing this, not only is fine temperature control possible, but the removal effect of impurity particles is excellent, so the selective vaporization of the deuteriumized hydrogen can be performed more effectively, and the purity improvement effect of the deuterium can be excellent.

[0073] In addition, in step (b) above, phase separation may occur due to the difference in boiling points of the deuterium-deuterium hydrogen mixed gas. More specifically, the deuterium exists in a liquid state and the deuterium hydrogen exists in a gaseous state, so that impurities can be effectively separated and removed by selectively exhausting the deuterium hydrogen.

[0074] (c) a step of obtaining high-purity gaseous deuterium by raising the temperature of the high-purity liquid deuterium from which the deuterium hydrogen has been removed to 25 to 100 K; may include a process of obtaining deuterium with improved purity by vaporizing it from the main heat exchanger (130) from which the deuterium hydrogen has been removed.

[0075] Including the above steps, it is possible to effectively remove the impurity deuteride hydrogen from the deuterium and deuteride hydrogen mixed gas and obtain high-purity deuterium, while simultaneously improving the recovery concentration and recovery rate of deuterium to be economically advantageous.

[0076] The present invention will be explained in more detail below with reference to examples and comparative examples.

[0077] However, the following examples and comparative examples are merely illustrative of the invention for further detailed explanation, and the invention is not limited to the following examples and comparative examples.

[0078] <Experimental Method>

[0079] For a deuterium-hydrogen deuteride mixed gas at a temperature of 300K and a hydrogen deuteride concentration of 1666 ppm,

[0080] (a) A deuterium-deuterium mixed gas injected through an inlet at one end of a cooling pipe (120) provided in a cryogenic distillation apparatus for separating and purifying deuterium was pre-cooled to a temperature of 70 to 80 K. Next, (b) the pre-cooled mixed gas was introduced into a main heat exchanger (130) and cooled to a temperature of 20 to 25 K to separate and remove the deuterium, which is an impurity. Then, (c) the high-purity liquid deuterium from which the deuterium was removed was heated to 100 K to obtain high-purity gaseous deuterium.

[0081] <Example 1>

[0082] According to the above experimental method, hydrogen deuterated was removed from the deuterium-hydrogen deuterated mixture gas and deuterium was obtained.

[0083] <Example 2>

[0084] Except for the fact that a heating film and a demister filter are provided inside the main heat exchanger (130) in step (b) above, hydrogen dehydrogenation is removed from the mixed gas and deuterium is obtained in the same manner as in Example 1.

[0085] <Comparative Example 1>

[0086] Except for not including the above step (a), hydrogen dehydrogenation was removed from the mixed gas in the same manner as in Example 1 and deuterium was obtained.

[0087] <Experimental Example 1> - Evaluation of Enhanced Effect of Deuterium Hydrogen Removal through Deuterium Separation and Purification

[0088] To evaluate the effect of removing hydrogen deuterated and improving purity through the separation and purification of deuterium performed by each example and comparative example, the concentration of hydrogen deuterated (HD) was measured using a high-precision mass spectrometer (Gas / MS, Finnigan MAT271) and is shown in below.

[0089] division Before purification Example 1 Example 2 Comparative Example 1 HD concentration (ppm) 1666 937 760 1542

[0090] As a result of evaluating the improved effect of removing deuterium hydrogen through deuterium separation and purification performed in each example and comparative example through , Examples 1 and 2, which include the pre-cooling process (a), showed a relatively lower concentration of deuterium hydrogen, an impurity, compared to Comparative Example 1, which does not include the pre-cooling process. Through this, it was confirmed that the effect of removing deuterium hydrogen, an impurity, is excellent when the pre-cooling process (a) is included.

[0091] In addition, in the case of Example 2, in which a heating film and a demister filter are provided inside the main heat exchanger (130), the concentration of hydrogen dehydrogenated was measured to be lower compared to Example 1, in which a heating film and a demister filter are not provided inside, confirming that the hydrogen dehydrogenated removal effect of the separation device is superior when a heating film and a demister filter are provided.

[0092] And Figure 3 shows the gas chromatography (GC) results after deuterium separation and purification, and by referring to Figure 3, it can be confirmed that deuterium separation and purification is clearly achieved.

[0093] <Experimental Example 2> - Evaluation of the Effect of Improving Deuterium Recovery Concentration and Recovery Rate through Deuterium Separation and Purification

[0094] To evaluate the effect of improving the recovery concentration and recovery rate of deuterium through the separation and purification of deuterium performed by each example and comparative example, the concentration of deuterium was measured using a low-vacuum gas injection quadrupole mass spectrometer (QMS), and the recovery concentration and recovery rate of deuterium obtained by each example and comparative example are shown in .

[0095] division Example 1 Example 2 Comparative Example 1 D2 Recovery Concentration (ppm) 47630 49724 41315 D2 Recovery Rate (%) 96.45 98.80 80.17

[0096] Based on the examples and comparative examples in , the effect of improving the purity and recovery rate of deuterium during the separation and purification process of deuterium was evaluated. As a result, it was confirmed that Examples 1 and 2, which include the pre-cooling process (a), had higher purity and recovery rates of deuterium compared to Comparative Example 1, which did not include the pre-cooling process. In addition, in the case of Example 2, in which a heating film and a demister filter are provided inside the main heat exchanger (130), it was confirmed that the purity and recovery rate of deuterium were further improved compared to Example 1, which did not have them.

[0097] As a result of the comprehensive evaluation, it was confirmed that Example 2 showed the lowest HD concentration, the highest D2 purity, and the highest recovery rate, indicating the best deuterium separation and purification effect.

[0098] Although preferred embodiments of the present invention have been described above, those skilled in the art will understand that various modifications and changes can be made to the present invention without departing from the technical spirit of the invention as described in the following claims. Explanation of the symbols

[0099] 10: Main body 11: Protective case 100: Preheat exchanger 110: Auxiliary chiller 120: Cooling tube 130: Main heat exchanger 140: Main chiller 150: Auxiliary heat exchanger 151: Activated carbon filter 160: Pump

Claims

Claim 1 A cryogenic distillation apparatus for separating and purifying deuterium comprises: a main body (10); a preheat exchanger (100) formed inside the main body (10); an auxiliary chiller (110) for preheating the preheat exchanger (100); a cooling pipe (120) installed spirally along the outside of the preheat exchanger (100), having an inlet formed at one end, through which a mixed gas containing deuterium (D2) and deuterated hydrogen (HD) is injected; and a main heat exchanger (130) coupled to the other end of the cooling pipe (120), into which the mixed gas flows from the cooling pipe (120), and which separates the deuterium and the deuterated hydrogen by cryogenic distillation of the mixed gas. A cryogenic distillation apparatus for separating and purifying deuterium equipped with a pre-cooling function, comprising: a main refrigerator (140) for cooling the main heat exchanger (130) to a predetermined target temperature; wherein the cooling pipe (120) is installed spirally along a groove provided outside the pre-heat exchanger (100), and a mixed gas including deuterium (D2) and hydrogen deuterated (HD) injected through the inlet moves spirally along the outside of the pre-heat exchanger (100) through the cooling pipe (120) and is pre-cooled to a temperature of 70 to 80 K, and the target temperature of the main refrigerator (140) is a temperature of 20 to 25 K. Claim 2 A cryogenic distillation apparatus for separating and purifying deuterium with a pre-cooling function, further comprising, in claim 1, an auxiliary heat exchanger (150) into which deuteriumized hydrogen gas separated from the main heat exchanger (130) is injected, and wherein an activated carbon filter (151) for adsorbing the deuteriumized hydrogen is provided inside the auxiliary heat exchanger (150). Claim 3 A cryogenic distillation apparatus for deuterium separation and purification equipped with a pre-cooling function, characterized in that, in claim 1, a heating film and a demister filter are provided inside the main heat exchanger (130). Claim 4 A cryogenic distillation apparatus for deuterium separation and purification equipped with a pre-cooling function, wherein, in claim 1, it further comprises a protective case (11) formed inside the main body (10), and the pre-heat exchanger (100), main heat exchanger (130), and auxiliary heat exchanger (150) are installed inside the protective case (11). Claim 5 delete Claim 6 delete

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