Hydrogen and helium liquefaction integrated system and method

Abstract

The invention relates to a hydrogen and helium liquefaction integrated system and method.The hydrogen and helium liquefaction integrated system comprises a first hydrogen and helium interaction heat exchanger (A1), a hydrogen liquefaction circulation main loop (I) and a helium liquefaction circulation loop, and the first hydrogen and helium interaction heat exchanger (A1) comprises a heat taking side, a first heat release side and a second heat release side; the first heat release side and the second heat release side are located on the two sides of the heat taking side correspondingly. The helium liquefaction circulation loop comprises a helium liquefaction circulation main loop (I) and a helium multi-stage liquefaction circulation branch (III), and the helium liquefaction circulation main loop (I) and the helium liquefaction circulation main loop (II) are integrated together through a first hydrogen-helium interaction heat exchanger (A1) and share cold energy, so that the loss of the cold energy is reduced, and the investment of equipment is also reduced.

Description

Technical Field

[0001] The present invention relates to the technical field of cryogenic liquefaction, and in particular to a hydrogen-helium liquefaction integrated system and method. Background Art

[0002] Hydrogen energy is a clean and renewable energy with a high energy density. Its special properties make it difficult to store at room temperature and pressure. The efficient use of hydrogen energy mainly relies on the method of liquefied hydrogen storage, which has the advantages of high density and low cost. Helium is the second most abundant element in the universe after hydrogen. The temperature of liquid helium is close to absolute zero, and it has important uses in ultra-low temperature fields such as low-temperature superconductivity, semiconductor production and atomic reactors. In the existing hydrogen liquefaction and helium liquefaction process, the system mainly relies on helium turboexpanders to provide the refrigeration required by the system, thereby realizing the liquefied storage of hydrogen and helium respectively. In the hydrogen and helium liquefaction processes, high liquefaction cold energy is required, and two independent hydrogen liquefaction systems and helium liquefaction systems need to be built separately, which has the disadvantages of large cold energy loss and large equipment investment.

[0003] The existing liquefaction of hydrogen and helium involves ultra-low temperature, and the liquefaction process requires a relatively low temperature and consumes a lot of energy. Since the existing liquefaction of hydrogen and helium requires very high liquefaction cold energy, the two independent liquefaction systems have the problems of complex equipment and high energy consumption. In summary, the existing hydrogen liquefaction system and helium liquefaction system are operated independently, and there are problems such as large cold energy loss and large equipment investment. Summary of the invention

[0004] In view of the above problems, the purpose of the present invention is to provide a hydrogen-helium liquefaction integrated system and method, which is used to solve the problems that the existing hydrogen liquefaction system and helium liquefaction system are operated independently, resulting in large cold energy loss and large equipment investment.

[0005] To achieve the above object, the present invention adopts the following technical solutions: In a first aspect, the present invention discloses a hydrogen-helium liquefaction integrated system, comprising: A first hydrogen-helium interactive heat exchanger comprises a heat-taking side, a first heat-releasing side and a second heat-releasing side, wherein the first heat-releasing side and the second heat-releasing side are respectively located on both sides of the heat-taking side; A main hydrogen liquefaction cycle loop comprises a hydrogen compressor, a first-stage hydrogen heat exchanger, a heat-taking side and a first heat-releasing side of a first hydrogen-helium inter-heat exchanger, a hydrogen hydraulic turbine expander and a liquid hydrogen tank, wherein the liquid hydrogen tank is provided with an inlet and a gas phase outlet; the outlet of the hydrogen compressor, the heat-taking side of the first-stage hydrogen heat exchanger, the heat-taking side of the first hydrogen-helium inter-heat exchanger, the hydrogen hydraulic turbine expander and the inlet of the liquid hydrogen tank are sequentially connected in series from front to back, and the gas phase outlet of the liquid hydrogen tank, the first heat-releasing side of the first hydrogen-helium inter-heat exchanger, the heat-releasing side of the first-stage hydrogen heat exchanger and the air inlet of the hydrogen compressor are sequentially connected in series from back to front, thereby forming the main hydrogen liquefaction cycle loop; A helium liquefaction circulation loop comprises a helium liquefaction circulation main loop and a helium multi-stage liquefaction circulation branch, wherein the helium liquefaction circulation main loop comprises a helium compressor, a helium first-stage heat exchanger, a helium expander and a second heat release side of the first hydrogen-helium interactive heat exchanger, wherein the outlet of the helium compressor, the heat collection side of the helium first-stage heat exchanger, the helium expander, the second heat release side of the first hydrogen-helium interactive heat exchanger, the heat release side of the helium first-stage heat exchanger and the air inlet of the helium compressor are sequentially connected in series, thereby forming a helium liquefaction circulation main loop; the helium multi-stage liquefaction circulation branch is connected in parallel with the helium expander; The helium multi-stage liquefaction circulation branch is used to form a liquid helium product after the helium medium flowing out of the first-stage helium heat exchanger undergoes multi-stage heat exchanger heat absorption and expansion cooling; The helium multi-stage liquefaction circulation branch includes a liquid helium tank for storing liquid helium products.

[0006] Furthermore, the hydrogen-helium liquefaction integrated system further includes a second hydrogen-helium interactive heat exchanger, wherein the second hydrogen-helium interactive heat exchanger includes a heat release side, a first heat extraction side and a second heat extraction side, and the first heat extraction side and the second heat extraction side are respectively located on both sides of the heat release side; The helium multi-stage liquefaction circulation branch includes a helium second-stage heat exchanger, a heat release side and a first heat extraction side of a second hydrogen-helium interactive heat exchanger, a helium fourth-stage heat exchanger, a helium hydraulic turbine expander and a liquid helium tank. The outlet of the heat-taking side of the helium first-stage heat exchanger, the heat-taking side of the helium second-stage heat exchanger, the first heat-taking side of the second hydrogen-helium interactive heat exchanger, the heat-taking side of the helium fourth-stage heat exchanger, the helium hydraulic turbine expander, the liquid helium tank, the heat-releasing side of the helium fourth-stage heat exchanger, the heat-releasing side of the second hydrogen-helium interactive heat exchanger, the heat-releasing side of the helium second-stage heat exchanger and the inlet of the second heat-releasing side of the first hydrogen-helium interactive heat exchanger are sequentially connected in series to form the helium multi-stage liquefaction circulation branch.

[0007] Furthermore, a first switch valve is provided on the pipeline connecting the outlet of the heat-taking side of the first-stage helium heat exchanger and the inlet of the heat-taking side of the second-stage helium heat exchanger; a second switch valve is provided on the pipeline connecting the outlet of the heat-releasing side of the second-stage helium heat exchanger and the inlet of the second heat-releasing side of the first hydrogen-helium interactive heat exchanger.

[0008] Furthermore, the hydrogen-helium liquefaction integrated system also includes a liquid hydrogen recovery circulation branch, and the liquid hydrogen tank is equipped with a liquid phase outlet; the liquid phase outlet of the liquid hydrogen tank is connected to the inlet of the second heat-taking side of the second hydrogen-helium interactive heat exchanger through a pipeline, and the outlet of the second heat-taking side of the second hydrogen-helium interactive heat exchanger is connected to the inlet of the first heat-releasing side of the first hydrogen-helium interactive heat exchanger through a pipeline, thereby forming the liquid hydrogen recovery circulation branch.

[0009] Furthermore, a third switch valve is provided on the pipeline connecting the liquid phase outlet of the liquid hydrogen tank and the inlet of the second heat extraction side of the second hydrogen-helium interactive heat exchanger; a fourth switch valve is provided on the pipeline connecting the outlet of the first heat extraction side of the second hydrogen-helium interactive heat exchanger and the inlet of the second heat release side of the first hydrogen-helium interactive heat exchanger.

[0010] In a second aspect, the present invention further discloses a hydrogen-helium liquefaction method, comprising: Liquefaction of hydrogen: hydrogen raw material is introduced, which is first pressurized, then subjected to heat absorption and cooling in the primary heat exchanger, heat absorption and cooling in the secondary heat exchanger, and expansion and cooling to form liquid hydrogen products, which are stored in liquid hydrogen tanks. The hydrogen gas flowing out of the liquid hydrogen tank is heated up after passing through the secondary heat exchanger and the primary heat exchanger in reverse order to release heat and become hydrogen gas at room temperature. The hydrogen gas at room temperature is mixed with the helium raw material and introduced again to form a circulating liquefaction of hydrogen gas. Liquefaction of helium: the helium raw material is introduced, which is first pressurized, and then separated into two parts after passing through a primary heat exchanger to absorb heat and cool down. One part of the helium is successively passed through a multi-stage heat exchanger to absorb heat and cool down, and then expanded and cooled down to form a liquid helium product, which is stored in a liquid helium tank; the other part of the helium is expanded and cooled down, and then mixed with the helium gas flowing out of the liquid helium tank and successively passed through a multi-stage heat exchanger in reverse order to release heat and heat up, and then passed through two heat exchangers to absorb heat and heat up to become normal temperature helium gas, and the normal temperature helium gas is mixed with the helium raw material again and introduced again to form a circulating liquefaction of helium gas; The liquefaction process of the hydrogen and the liquefaction process of the helium are performed simultaneously or separately.

[0011] Specifically, using the above-mentioned hydrogen-helium liquefaction integrated system, the liquefaction of hydrogen includes the following steps: introducing helium raw material into the air inlet of the hydrogen compressor; After the hydrogen is pressurized by the hydrogen compressor, it is cooled after absorbing heat on the heat-taking side of the first-stage hydrogen heat exchanger and the heat-taking side of the first hydrogen-helium interactive heat exchanger, and is cooled after being decompressed and expanded by the hydrogen hydraulic turbine expander to form liquid hydrogen products, which are then stored in liquid hydrogen tanks. The low-temperature gaseous hydrogen in the liquid hydrogen tank flows out from the gas phase outlet, and is heated up after passing through the first heat release side of the first hydrogen-helium interactive heat exchanger and the heat release side of the hydrogen first-stage heat exchanger to release heat and become room-temperature gaseous hydrogen. The room-temperature gaseous hydrogen is mixed with the helium raw material and then reintroduced to form a circulating liquefaction of hydrogen gas.

[0012] Specifically, the liquefaction of helium includes the following steps: Open the first on-off valve and the second on-off valve; Introducing helium into the air inlet of the helium compressor; The helium is first pressurized by a helium compressor, and then absorbed heat and cooled on the heat-taking side of the first-stage helium heat exchanger, and then divided into two parts. One part of the helium is successively absorbed heat and cooled on the heat-taking side of the second-stage helium heat exchanger, the first heat-taking side of the second hydrogen-helium exchanger, and the heat-taking side of the fourth-stage helium heat exchanger, and then decompressed, expanded and cooled by a helium hydraulic turbine expander to form a liquid helium product, which is stored in a liquid helium tank; the other part of the helium is decompressed, expanded and cooled by a helium expander, and then mixed with the low-temperature helium flowing out of the liquid helium tank. The gas is first mixed by passing through the heat release side of the fourth-stage helium heat exchanger, the first heat collection side of the second hydrogen-helium interactive heat exchanger, and the room-temperature gas helium obtained by heating up the heat collection side of the second-stage helium heat exchanger. Then, the gas is heated up by passing through the second heat release side of the first hydrogen-helium interactive heat exchanger and the heat release side of the first-stage helium heat exchanger to become room-temperature helium gas. After the room-temperature helium gas is mixed with the helium raw material again, it is reintroduced into the air inlet of the helium compressor to form a circulating liquefaction of the helium gas.

[0013] Furthermore, during the circulation and liquefaction of the helium gas, the third switch valve and the fourth switch valve are opened; the liquid hydrogen in the liquid hydrogen tank flows out from the liquid phase outlet, absorbs heat on the second heat-taking side of the second hydrogen-helium interactive heat exchanger, and then cools down, mixes with the low-temperature gaseous hydrogen flowing out from the gas phase outlet of the liquid hydrogen tank, and enters the inlet of the first heat-releasing side of the first hydrogen-helium interactive heat exchanger together.

[0014] Among them, when only hydrogen is introduced into the air inlet of the hydrogen compressor and helium is not introduced into the air inlet of the helium compressor, or when only hydrogen is introduced into the air inlet of the helium compressor and helium is not introduced into the air inlet of the hydrogen compressor, the process of liquefying the hydrogen or the process of liquefying the helium is carried out separately; when hydrogen and helium are introduced into the air inlets of the hydrogen compressor and the helium compressor respectively at the same time, the process of liquefying the hydrogen and the process of liquefying the helium are carried out simultaneously.

[0015] Compared with the prior art, the present invention has the following beneficial effects: (I) The present invention discloses a hydrogen-helium liquefaction integrated system, comprising a first hydrogen-helium interactive heat exchanger, a second hydrogen-helium interactive heat exchanger, a hydrogen liquefaction circulation main loop, a helium liquefaction circulation loop and a liquid hydrogen recovery circulation branch, wherein the helium liquefaction circulation loop comprises a helium liquefaction circulation main loop and a helium multi-stage liquefaction circulation branch, wherein the hydrogen liquefaction circulation main loop and the helium liquefaction circulation main loop are connected together through the first hydrogen-helium interactive heat exchanger, and the helium multi-stage liquefaction circulation branch and the liquid hydrogen recovery circulation branch are connected together through the second hydrogen-helium interactive heat exchanger, and the cold energy of the first hydrogen-helium interactive heat exchanger and the second hydrogen-helium interactive heat exchanger are shared respectively, which not only reduces the cold energy loss, but also reduces the number of equipment in the process, thereby reducing the investment in equipment.

[0016] (ii) The present invention discloses a hydrogen-helium liquefaction method, including the liquefaction of hydrogen and the liquefaction of helium, and the process of liquefaction of hydrogen and the process of liquefaction of helium are carried out simultaneously or separately, which can realize hydrogen liquefaction, helium liquefaction and simultaneous liquefaction of hydrogen and helium, which not only improves operability but also realizes liquid hydrogen cold energy recovery.

[0017] In addition, compared with independent hydrogen and helium liquefaction systems, the present invention also has the following beneficial effects: 1. The hydrogen hydraulic turbine expander and the helium expander adopt an integrated machine mode to realize the energy recovery of the helium expander. The low-temperature liquid hydrogen in the liquid hydrogen storage tank is introduced into the first hydrogen-helium interactive heat exchanger and the second hydrogen-helium interactive heat exchanger to increase the liquid helium production. The helium flow as a refrigerant also provides cooling capacity for the first hydrogen-helium interactive heat exchanger and the second hydrogen-helium interactive heat exchanger. The first hydrogen-helium interactive heat exchanger and the second hydrogen-helium interactive heat exchanger realize the recycling of liquid hydrogen cold energy. In addition, the added value of the hydraulic turbine - electric energy supplements the energy consumption of the helium compressor.

[0018] 2. Using hydraulic turbines to throttle high-pressure hydrogen and helium after liquefaction and subcooling can generate added value - electricity - compared with using JT valve throttling.

[0019] 3. Compared with independent hydrogen liquefaction systems and helium liquefaction systems, the hydrogen-helium liquefaction integrated system of the present invention reduces a helium expander between the helium second-stage heat exchanger and the second hydrogen-helium interactive heat exchanger, and uses the phase change cold energy of liquid hydrogen to provide cold energy for the second hydrogen-helium interactive heat exchanger, thereby simplifying equipment investment and realizing the recovery and utilization of liquid hydrogen cold energy.

[0020] 4. By adjusting the opening of the first switch valve or the third switch valve, the system cooling capacity and liquid hydrogen cooling energy can be utilized, and the liquefied production of hydrogen and helium can be realized. BRIEF DESCRIPTION OF THE DRAWINGS

[0021] Figure 1is a schematic diagram of the overall structure of the hydrogen-helium liquefaction integrated system provided in Example 1 of the present invention; Figure 2 is a schematic diagram of the structure of the main loop of the hydrogen liquefaction cycle provided in Example 1 of the present invention; Figure 3 is a schematic diagram of the structure of the main helium liquefaction cycle provided in Example 1 of the present invention; Figure 4 is a schematic structural diagram of a helium multi-stage liquefaction circulation branch provided in Example 1 of the present invention; Figure 5 It is a schematic diagram of the structure of the liquid hydrogen recovery circulation branch provided in Example 1 of the present invention. Description of reference numerals: A1-first hydrogen-helium interactive heat exchanger, A2-second hydrogen-helium interactive heat exchanger; Ⅰ-main hydrogen liquefaction cycle loop, 11-hydrogen compressor, 12-first stage hydrogen heat exchanger, 13-hydrogen hydraulic turbine expander, 14-liquid hydrogen tank; Ⅱ-helium liquefaction cycle main loop, 21-helium compressor, 22-helium first stage heat exchanger, 23-helium expander; III-helium multi-stage liquefaction circulation branch, 31-helium second stage heat exchanger, 32-helium fourth stage heat exchanger, 33-helium hydraulic turbine expander, 34-liquid helium tank, 35-first switch valve, 36-second switch valve; IV-liquid hydrogen recovery circulation branch, 41-third switch valve, 42-fourth switch valve. DETAILED DESCRIPTION

[0022] The exemplary embodiments of the present invention will be described in more detail below with reference to the accompanying drawings. Although the exemplary embodiments of the present invention are shown in the accompanying drawings, it should be understood that the present invention can be implemented in various forms and should not be limited by the embodiments described herein. On the contrary, these embodiments are provided in order to enable a more thorough understanding of the present invention and to fully convey the scope of the present invention to those skilled in the art.

[0023] In order to solve the problems that the existing hydrogen liquefaction system and helium liquefaction system are independently operated, resulting in large cold energy loss and large equipment investment, the present invention discloses a hydrogen-helium liquefaction integrated system, comprising a first hydrogen-helium interactive heat exchanger, a second hydrogen-helium interactive heat exchanger, a hydrogen liquefaction circulation main loop, a helium liquefaction circulation loop and a liquid hydrogen recovery circulation branch, wherein the helium liquefaction circulation loop comprises a helium liquefaction circulation main loop and a helium multi-stage liquefaction circulation branch, wherein the hydrogen liquefaction circulation main loop and the helium liquefaction circulation main loop are connected together through the first hydrogen-helium interactive heat exchanger, and the helium multi-stage liquefaction circulation branch and the liquid hydrogen recovery circulation branch are connected together through the second hydrogen-helium interactive heat exchanger, and the cold energy of the first hydrogen-helium interactive heat exchanger and the second hydrogen-helium interactive heat exchanger are shared respectively, which not only reduces the cold energy loss, but also reduces the number of equipment in the process, thereby reducing the investment in equipment.

[0024] Example 1: A hydrogen-helium liquefaction integrated system Embodiment 1 provides a hydrogen-helium liquefaction integrated system, and its structure and connection relationship are described in detail below with reference to the accompanying drawings.

[0025] refer to Figure 1 The hydrogen-helium liquefaction integrated system includes a first hydrogen-helium interactive heat exchanger A1, a second hydrogen-helium interactive heat exchanger A2, a hydrogen liquefaction cycle main loop I, a helium liquefaction cycle loop and a liquid hydrogen recovery cycle branch IV, wherein the helium liquefaction cycle loop includes a helium liquefaction cycle main loop II and a helium multi-stage liquefaction cycle branch III.

[0026] The first hydrogen-helium interactive heat exchanger A1 includes a heat-taking side, a first heat-releasing side and a second heat-releasing side, and the first heat-releasing side and the second heat-releasing side are respectively located on both sides of the heat-taking side. Specifically, the heat-taking side, the first heat-releasing side and the second heat-releasing side of the first hydrogen-helium interactive heat exchanger A1 are respectively configured with an inlet and an outlet.

[0027] The heat-taking side is used to absorb the heat of the medium, so that the medium cools down and becomes a low-temperature medium; the heat-releasing side is used to give heat to the medium, so that the medium heats up and becomes a high-temperature medium.

[0028] The second hydrogen-helium interactive heat exchanger A2 includes a heat release side, a first heat extraction side, and a second heat extraction side, and the first heat extraction side and the second heat extraction side are respectively located on both sides of the heat release side. Specifically, the heat extraction side, the first heat release side, and the second heat release side of the second hydrogen-helium interactive heat exchanger A2 are respectively configured with an inlet and an outlet.

[0029] refer to Figure 2 The main hydrogen liquefaction cycle loop I includes a hydrogen compressor 11, a first-stage hydrogen heat exchanger 12, a heat-taking side and a first heat-releasing side of a first hydrogen-helium interactive heat exchanger A1, a hydrogen hydraulic turbine expander 13 and a liquid hydrogen tank 14.

[0030] Specifically, the hydrogen compressor 11 includes an inlet and an outlet.

[0031] Specifically, the first-stage hydrogen heat exchanger 12 includes a heat release side and a heat intake side, and the heat release side and the heat intake side are respectively provided with an inlet and an outlet.

[0032] Specifically, the liquid hydrogen tank 14 is configured with an inlet, a gas phase outlet and a liquid phase outlet.

[0033] The outlet of the hydrogen compressor 11, the heat-taking side of the first-stage hydrogen heat exchanger 12, the heat-taking side of the first hydrogen-helium interactive heat exchanger A1, the hydrogen hydraulic turbine expander 13 and the inlet of the liquid hydrogen tank 14 are connected in series from front to back, and the gas phase outlet of the liquid hydrogen tank 14, the first heat-releasing side of the first hydrogen-helium interactive heat exchanger A1, the heat-releasing side of the first-stage hydrogen heat exchanger 12 and the air inlet of the hydrogen compressor 11 are connected in series from back to front, thereby forming the hydrogen liquefaction cycle main loop I.

[0034] As a specific connection mode, the outlet of the hydrogen compressor 11 is connected to the inlet of the heat-taking side of the first-stage hydrogen heat exchanger 12, the outlet of the heat-taking side of the first-stage hydrogen heat exchanger 12 is connected to the inlet of the heat-taking side of the first hydrogen-helium interactive heat exchanger A1, the outlet of the heat-taking side of the first hydrogen-helium interactive heat exchanger A1 is connected to the inlet of the hydrogen hydraulic turbine expander 13, and the outlet of the hydrogen hydraulic turbine expander 13 is connected to the inlet of the liquid hydrogen tank 14, thereby realizing the above-mentioned "connected in series from front to back". The gas phase outlet of the liquid hydrogen tank 14 is connected to the inlet of the first heat-releasing side of the first hydrogen-helium interactive heat exchanger A1, the outlet of the first heat-releasing side of the heat-taking side of the first hydrogen-helium interactive heat exchanger A1 is connected to the inlet of the heat-releasing side of the first-stage hydrogen heat exchanger 12, and the outlet of the heat-releasing side of the first-stage hydrogen heat exchanger 12 is connected to the air inlet of the hydrogen compressor 11, thereby realizing the above-mentioned "connected in series from back to front".

[0035] refer to Figure 3 The helium liquefaction cycle main loop II includes a helium compressor 21, a helium first-stage heat exchanger 22, a helium expander 23 and the second heat release side of the first hydrogen-helium interactive heat exchanger A1.

[0036] The outlet of the helium compressor 21, the heat-taking side of the first-stage helium heat exchanger 22, the helium expander 23, the second heat-releasing side of the first hydrogen-helium interactive heat exchanger A1, the heat-releasing side of the first-stage helium heat exchanger 22 and the air inlet of the helium compressor 21 are connected in series in sequence, thereby forming a helium liquefaction cycle main loop II.

[0037] Specifically, the helium compressor 21 includes an inlet and an outlet.

[0038] Specifically, the helium first-stage heat exchanger 22 includes a heat release side and a heat intake side, and the heat release side and the heat intake side are respectively configured with an inlet and an outlet.

[0039] As a specific connection method, the outlet of the helium compressor 21 is connected to the inlet of the heat-taking side of the helium first-stage heat exchanger 22, and the outlet of the heat-taking side of the helium first-stage heat exchanger 22 is connected to the inlet of the helium expander 23; the outlet of the helium expander 23 is connected to the inlet of the second heat-releasing side of the first hydrogen-helium interactive heat exchanger A1, and the outlet of the second heat-releasing side of the first hydrogen-helium interactive heat exchanger A1 is connected to the inlet of the heat-releasing side of the helium first-stage heat exchanger 22, and the outlet of the heat-releasing side of the helium first-stage heat exchanger 22 is connected to the inlet of the helium compressor 21, thereby forming a circulation loop.

[0040] Among them, the hydrogen liquefaction cycle main loop I and the helium liquefaction cycle main loop II are used together to realize the liquefaction of hydrogen.

[0041] The helium multi-stage liquefaction circulation branch III is connected in parallel with the helium expander 23; The helium multi-stage liquefaction circulation branch III is used to form a liquid helium product after the helium medium flowing out from the first-stage helium heat exchanger 22 undergoes multi-stage heat exchanger heat absorption and expansion cooling; The helium multi-stage liquefaction circulation branch III includes a liquid helium tank 34 for storing liquid helium products.

[0042] refer to Figure 4 The helium multi-stage liquefaction circulation branch III includes a helium second-stage heat exchanger 31, a heat release side and a first heat extraction side of a second hydrogen-helium interactive heat exchanger A2, a helium fourth-stage heat exchanger 32, a helium hydraulic turbine expander 33 and a liquid helium tank 34. The outlet of the heat-taking side of the helium first-stage heat exchanger 22, the heat-taking side of the helium second-stage heat exchanger 31, the first heat-taking side of the second hydrogen-helium interactive heat exchanger A2, the heat-taking side of the helium fourth-stage heat exchanger 32, the helium hydraulic turbine expander 33, the liquid helium tank 34, the heat-releasing side of the helium fourth-stage heat exchanger 32, the heat-releasing side of the second hydrogen-helium interactive heat exchanger A2, the heat-releasing side of the helium second-stage heat exchanger 31 and the inlet of the second heat-releasing side of the first hydrogen-helium interactive heat exchanger A1 are connected in series in sequence to form the helium multi-stage liquefaction circulation branch III.

[0043] Specifically, the helium second-stage heat exchanger 31 includes a heat release side and a heat extraction side, and the heat release side and the heat extraction side are respectively provided with an inlet and an outlet.

[0044] Specifically, the helium fourth-stage heat exchanger 32 includes a heat release side and a heat extraction side, and the heat release side and the heat extraction side are respectively provided with an inlet and an outlet.

[0045] Specifically, the liquid helium tank 34 includes an inlet and a gas phase outlet.

[0046] As a specific connection method, the outlet of the heat-taking side of the helium first-stage heat exchanger 22 is connected to the inlet of the heat-taking side of the helium second-stage heat exchanger 31 through a pipeline; the outlet of the heat-taking side of the helium second-stage heat exchanger 31 is connected to the inlet of the first heat-taking side of the second hydrogen-helium interactive heat exchanger A2; the outlet of the first heat-taking side of the second hydrogen-helium interactive heat exchanger A2 is connected to the inlet of the heat-taking side of the helium fourth-stage heat exchanger 32; the outlet of the heat-taking side of the helium fourth-stage heat exchanger 32 is connected to the helium liquid The inlet of the helium hydraulic turbine expander 33 is connected; the outlet of the helium hydraulic turbine expander 33 is connected to the inlet of the liquid helium tank 34; the gas phase outlet of the liquid helium tank 34 is connected to the inlet of the heat release side of the second hydrogen-helium interactive heat exchanger A2, and the outlet of the heat release side of the second hydrogen-helium interactive heat exchanger A2 is connected to the inlet of the heat release side of the helium second-stage heat exchanger 31; the outlet of the heat release side of the helium second-stage heat exchanger 31 is connected to the inlet of the second heat release side of the first hydrogen-helium interactive heat exchanger A1 through a pipeline.

[0047] In order to facilitate the control of the medium flowing from the helium liquefaction cycle main loop II to the helium multi-stage liquefaction cycle branch III, a first switch valve 35 is provided on the pipeline connecting the outlet of the heat-taking side of the helium first-stage heat exchanger 22 and the inlet of the heat-taking side of the helium second-stage heat exchanger 31.

[0048] In order to facilitate the control of the medium returning from the helium multi-stage liquefaction cycle branch III to the helium liquefaction cycle main loop II, a second switch valve 36 is provided on the pipeline connecting the outlet of the heat release side of the helium second-stage heat exchanger 31 and the inlet of the second heat release side of the first hydrogen-helium interactive heat exchanger A1.

[0049] Preferably, the second switch valve 36 is a one-way valve that only allows the medium to flow from the outlet of the heat release side of the helium second-stage heat exchanger 31 to the inlet of the second heat release side of the first hydrogen-helium interactive heat exchanger A1 but not to flow in the opposite direction.

[0050] Among them, by controlling the opening size of the first switch valve 35, the amount of cold energy exchanged between the first hydrogen-helium interactive heat exchanger A1 and the hydrogen liquefaction cycle main loop I is controlled, that is, when the hydrogen flow rate is large, the openings of the first switch valve 35 and the second switch valve 36 are reduced, thereby increasing the cold energy of the first hydrogen-helium interactive heat exchanger A1.

[0051] refer to Figure 5 The liquid phase outlet of the liquid hydrogen tank 14 is connected to the inlet of the second heat extraction side of the second hydrogen-helium interactive heat exchanger A2 through a pipeline, and the outlet of the second heat extraction side of the second hydrogen-helium interactive heat exchanger A2 is connected to the inlet of the first heat release side of the first hydrogen-helium interactive heat exchanger A1 through a pipeline, thereby forming the liquid hydrogen recovery circulation branch IV.

[0052] As a specific connection method, the liquid phase outlet of the liquid hydrogen tank 14 is connected to the inlet of the second heat-taking side of the second hydrogen-helium interactive heat exchanger A2 through a pipeline, and the outlet of the second heat-taking side of the second hydrogen-helium interactive heat exchanger A2 is connected to the inlet of the first heat-releasing side of the first hydrogen-helium interactive heat exchanger A1 through a pipeline, thereby forming the liquid hydrogen recovery circulation branch IV.

[0053] In order to control the medium to flow from the liquid phase outlet of the liquid hydrogen tank 14 to the inlet of the second heat extraction side of the second hydrogen-helium interactive heat exchanger A2, a third switch valve 41 is provided on the pipeline connecting the liquid phase outlet of the liquid hydrogen tank 14 and the inlet of the second heat extraction side of the second hydrogen-helium interactive heat exchanger A2.

[0054] In order to control the medium to return from the outlet of the second heat-taking side of the second hydrogen-helium interactive heat exchanger A2 to the inlet of the first heat-releasing side of the first hydrogen-helium interactive heat exchanger A1, a fourth switch valve 42 is provided on the pipeline connecting the outlet of the second heat-releasing side of the second hydrogen-helium interactive heat exchanger A2 and the inlet of the first heat-releasing side of the first hydrogen-helium interactive heat exchanger A1.

[0055] Preferably, the fourth switch valve 42 is a one-way valve that only allows the medium to flow from the outlet of the second heat extraction side of the second hydrogen-helium interactive heat exchanger A2 to the inlet of the first heat release side of the first hydrogen-helium interactive heat exchanger A1 but not to flow in the opposite direction.

[0056] Among them, by adjusting the opening of the third switch valve 41, the liquefied amount of helium can be controlled, that is, when the liquefied flow rate of helium is large, the opening of the third switch valve 41 is increased, thereby increasing the cold energy of the second hydrogen-helium interactive heat exchanger A2.

[0057] Example 2: A method for liquefying hydrogen and helium Embodiment 2 of the present invention provides a hydrogen-helium liquefaction method, comprising the following steps: Liquefaction of hydrogen: hydrogen raw material is introduced, which is first pressurized, and then undergoes heat absorption and cooling in the primary heat exchanger and heat absorption and cooling in the secondary heat exchanger, as well as expansion and cooling, to form a liquid hydrogen product, which is stored in the liquid hydrogen tank 14; the hydrogen gas flowing out of the liquid hydrogen tank 14 is heated up after passing through the secondary heat exchanger and the primary heat exchanger in reverse order to release heat, and becomes room-temperature hydrogen gas, which is mixed with the helium raw material and introduced again to form a circulating liquefaction of hydrogen gas; Liquefaction of helium: the helium raw material is introduced, which is first pressurized, and then separated into two parts after passing through a primary heat exchanger to absorb heat and cool down. One part of the helium is successively passed through a multi-stage heat exchanger to absorb heat and cool down, and then expanded and cooled down to form a liquid helium product, which is stored in the liquid helium tank 34; the other part of the helium is expanded and cooled down, and then mixed with the helium gas flowing out of the liquid helium tank 34 and successively passed through a multi-stage heat exchanger in reverse order to release heat and heat up, and then passed through two heat exchangers to absorb heat and heat up to become normal temperature helium gas, and the normal temperature helium gas is mixed with the helium raw material again and introduced again to form a circulating liquefaction of the helium gas; The liquefaction process of the hydrogen and the liquefaction process of the helium are performed simultaneously or separately.

[0058] Using the hydrogen-helium liquefaction integrated system of Example 1, the liquefaction of hydrogen includes the following steps: Introducing helium raw material into the air inlet of the hydrogen compressor 11; After the hydrogen is pressurized by the hydrogen compressor 11, it is cooled after absorbing heat at the heat-taking side of the first-stage hydrogen heat exchanger 12 and the heat-taking side of the first hydrogen-helium interactive heat exchanger A1, and is cooled after being decompressed and expanded by the hydrogen hydraulic turbine expander 13 to form a liquid hydrogen product, which is stored in the liquid hydrogen tank 14. The low-temperature gaseous hydrogen in the liquid hydrogen tank 14 flows out from the gas phase outlet, and is heated up after passing through the first heat release side of the first hydrogen-helium interactive heat exchanger A1 and the heat release side of the hydrogen first-stage heat exchanger 12 to release heat and become room-temperature gaseous hydrogen. The room-temperature gaseous hydrogen is mixed with the helium raw material and then reintroduced to form a circulating liquefaction of the hydrogen gas.

[0059] Furthermore, the liquefaction of helium comprises the following steps: Open the first on-off valve 35 and the second on-off valve 36; Introducing helium into the air inlet of the helium compressor 21; The helium is first pressurized by the helium compressor 21, and then absorbed heat and cooled on the heat-taking side of the first-stage helium heat exchanger 22, and then divided into two parts. One part of the helium is sequentially absorbed heat and cooled on the heat-taking side of the helium second-stage heat exchanger 31, the first heat-taking side of the second hydrogen-helium interactive heat exchanger A2, and the heat-taking side of the helium fourth-stage heat exchanger 32, and then reduced in pressure, expanded and cooled by the helium hydraulic turbine expander 33 to form a liquid helium product, which is stored in the liquid helium tank 34; the other part of the helium is reduced in pressure, expanded and cooled by the helium expander 23, and then mixed with the low-pressure helium gas flowing out of the liquid helium tank 34. The warm helium gas passes through the heat release side of the fourth-stage helium heat exchanger 32, the first heat collection side of the second hydrogen-helium interactive heat exchanger A2, and the heat collection side of the second-stage helium heat exchanger 31 in sequence to release heat and then heat up to obtain room-temperature gas helium, and is mixed for the first time, and then passes through the second heat release side of the first hydrogen-helium interactive heat exchanger A1 and the heat release side of the first-stage helium heat exchanger 22 to release heat and then heat up to become room-temperature helium gas. The room-temperature helium gas is mixed with the helium raw material again and then reintroduced into the air inlet of the helium compressor 21 to form a circulating liquefaction of the helium gas.

[0060] Furthermore, during the circulation and liquefaction of the helium gas, the third switch valve 41 and the fourth switch valve 42 are opened; The liquid hydrogen in the liquid hydrogen tank 14 flows out from the liquid phase outlet, absorbs heat at the second heat extraction side of the second hydrogen-helium interactive heat exchanger A2 and then cools down, mixes with the low-temperature gaseous hydrogen flowing out from the gas phase outlet of the liquid hydrogen tank 14, and enters the inlet of the first heat release side of the first hydrogen-helium interactive heat exchanger A1 together.

[0061] It is worth mentioning that the hydrogen-helium liquefaction method can realize three working conditions: pure hydrogen liquefaction, pure helium liquefaction and simultaneous liquefaction of hydrogen and helium, that is, the above-mentioned hydrogen liquefaction process and the above-mentioned helium liquefaction process are carried out simultaneously or separately.

[0062] Among them, when only hydrogen is introduced into the air inlet of the hydrogen compressor 11 and helium is not introduced into the air inlet of the helium compressor 21, or when only hydrogen is introduced into the air inlet of the helium compressor 21 and helium is not introduced into the air inlet of the hydrogen compressor 11, the process of liquefying the hydrogen or the process of liquefying the helium are carried out separately.

[0063] When hydrogen and helium are introduced into the air inlets of the hydrogen compressor 11 and the helium compressor 21 respectively at the same time, the liquefaction process of the hydrogen and the liquefaction process of the helium are carried out simultaneously.

[0064] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present invention, rather than to limit it. Although the present invention has been described in detail with reference to the aforementioned embodiments, those skilled in the art should understand that they can still modify the technical solutions described in the aforementioned embodiments, or make equivalent replacements for some of the technical features therein. However, these modifications or replacements do not deviate the essence of the corresponding technical solutions from the spirit and scope of the technical solutions of the embodiments of the present invention.

Claims

1. A hydrogen-helium liquefaction integrated system, characterized in that: include A first hydrogen-helium mutual heat exchanger (A1) comprises a heat-taking side, a first heat-releasing side and a second heat-releasing side, wherein the first heat-releasing side and the second heat-releasing side are respectively located on both sides of the heat-taking side; A main hydrogen liquefaction cycle loop (I) comprises a hydrogen compressor (11), a first-stage hydrogen heat exchanger (12), a heat-taking side and a first heat-releasing side of a first hydrogen-helium inter-heat exchanger (A1), a hydrogen hydraulic turbine expander (13) and a liquid hydrogen tank (14), wherein the liquid hydrogen tank (14) is provided with an inlet and a gas phase outlet; the outlet of the hydrogen compressor (11), the heat-taking side of the first-stage hydrogen heat exchanger (12), the heat-taking side of the first hydrogen-helium inter-heat exchanger (A1), the hydrogen hydraulic turbine expander (13) and the inlet of the liquid hydrogen tank (14) are sequentially connected in series from front to back, and the gas phase outlet of the liquid hydrogen tank (14), the first heat-releasing side of the first hydrogen-helium inter-heat exchanger (A1), the heat-releasing side of the first-stage hydrogen heat exchanger (12) and the gas inlet of the hydrogen compressor (11) are sequentially connected in series from back to front, thereby forming the main hydrogen liquefaction cycle loop (I); A helium liquefaction circulation loop comprises a helium liquefaction circulation main loop (II) and a helium multi-stage liquefaction circulation branch (III), wherein the helium liquefaction circulation main loop (II) comprises a helium compressor (21), a helium first-stage heat exchanger (22), a helium expander (23) and a second heat release side of the first hydrogen-helium mutual heat exchanger (A1), wherein the outlet of the helium compressor (21), the heat collection side of the first-stage helium heat exchanger (22), the helium expander (23), the second heat release side of the first hydrogen-helium mutual heat exchanger (A1), the heat release side of the first-stage helium heat exchanger (22) and the air inlet of the helium compressor (21) are sequentially connected in series, thereby forming the helium liquefaction circulation main loop (II); the helium multi-stage liquefaction circulation branch (III) is connected in parallel with the helium expander (23); The helium multi-stage liquefaction circulation branch (III) is used to form a liquid helium product after the helium medium flowing out from the first-stage helium heat exchanger (22) undergoes multi-stage heat exchanger heat absorption and expansion cooling; The helium multi-stage liquefaction circulation branch (III) comprises a liquid helium tank (34) for storing liquid helium finished products.

2. The hydrogen-helium liquefaction integrated system according to claim 1, characterized in that: It also includes a second hydrogen-helium interactive heat exchanger (A2), wherein the second hydrogen-helium interactive heat exchanger (A2) includes a heat release side, a first heat extraction side, and a second heat extraction side, wherein the first heat extraction side and the second heat extraction side are respectively located on both sides of the heat release side; The helium multi-stage liquefaction circulation branch (III) comprises a helium second-stage heat exchanger (31), a heat release side and a first heat extraction side of a second hydrogen-helium interactive heat exchanger (A2), a helium fourth-stage heat exchanger (32), a helium hydraulic turbine expander (33) and a liquid helium tank (34). The outlet of the heat-taking side of the helium first-stage heat exchanger (22), the heat-taking side of the helium second-stage heat exchanger (31), the first heat-taking side of the second hydrogen-helium interactive heat exchanger (A2), the heat-taking side of the helium fourth-stage heat exchanger (32), the helium hydraulic turbine expander (33), the liquid helium tank (34), the heat-releasing side of the helium fourth-stage heat exchanger (32), the heat-releasing side of the second hydrogen-helium interactive heat exchanger (A2), the heat-releasing side of the helium second-stage heat exchanger (31), and the inlet of the second heat-releasing side of the first hydrogen-helium interactive heat exchanger (A1) are sequentially connected in series to form the helium multi-stage liquefaction circulation branch (III).

3. The hydrogen-helium liquefaction integrated system according to claim 2, characterized in that: A first switch valve (35) is provided on a pipeline connecting the outlet of the heat extraction side of the first-stage helium heat exchanger (22) and the inlet of the heat extraction side of the second-stage helium heat exchanger (31); A second on-off valve (36) is provided on a pipeline connecting the outlet of the heat release side of the helium second-stage heat exchanger (31) and the inlet of the second heat release side of the first hydrogen-helium interactive heat exchanger (A1).

4. The hydrogen-helium liquefaction integrated system according to claim 1, characterized in that: It also includes a liquid hydrogen recovery circulation branch (IV), The liquid hydrogen tank (14) is provided with a liquid phase outlet; The liquid phase outlet of the liquid hydrogen tank (14) is connected to the inlet of the second heat extraction side of the second hydrogen-helium interactive heat exchanger (A2) through a pipeline, and the outlet of the second heat extraction side of the second hydrogen-helium interactive heat exchanger (A2) is connected to the inlet of the first heat release side of the first hydrogen-helium interactive heat exchanger (A1) through a pipeline, thereby forming the liquid hydrogen recovery circulation branch (IV).

5. The hydrogen-helium liquefaction integrated system according to claim 2, characterized in that: A third switch valve (41) is provided on a pipeline communicating between the liquid phase outlet of the liquid hydrogen tank (14) and the inlet of the second heat extraction side of the second hydrogen-helium interactive heat exchanger (A2); A fourth switch valve (42) is provided on a pipeline connecting the outlet of the first heat extraction side of the second hydrogen-helium interactive heat exchanger (A2) and the inlet of the second heat release side of the first hydrogen-helium interactive heat exchanger (A1).

6. A method for liquefying hydrogen and helium, characterized in that: include: Liquefaction of hydrogen: hydrogen raw material is introduced, the hydrogen raw material is first pressurized, then absorbs heat and cools in the first heat exchanger and absorbs heat and cools in the second heat exchanger and expands and cools, to form a liquid hydrogen product, which is stored in a liquid hydrogen tank (14); wherein the hydrogen gas flowing out of the liquid hydrogen tank (14) is successively reversely passed through the second heat exchanger and the first heat exchanger to release heat and then heated up to become room temperature hydrogen gas, the room temperature hydrogen gas is mixed with the helium raw material and introduced again, to form a circulating liquefaction of hydrogen gas; Liquefaction of helium: introducing a helium raw material, which is first pressurized, and then subjected to heat absorption and temperature reduction in a primary heat exchanger, and then divided into two parts. One part of the helium is subjected to heat absorption and temperature reduction in a multi-stage heat exchanger in sequence, and then expanded and cooled to form a liquid helium product, which is stored in a liquid helium tank (34); the other part of the helium is subjected to expansion and temperature reduction, and then mixed with the helium gas discharged from the liquid helium tank (34) and subjected to heat release and temperature increase in a reverse direction through the multi-stage heat exchanger in sequence, and then subjected to heat absorption and temperature increase through two heat exchangers to become normal temperature helium gas. The normal temperature helium gas is mixed with the helium raw material again and then introduced again, thereby forming a cyclic liquefaction of the helium gas; The liquefaction process of the hydrogen and the liquefaction process of the helium are performed simultaneously or separately.

7. The hydrogen-helium liquefaction method according to claim 6, characterized in that: Using the hydrogen-helium liquefaction integrated system according to any one of claims 1 to 5, the liquefaction of hydrogen comprises the following steps: Introducing helium raw material into the air inlet of the hydrogen compressor (11); After the hydrogen is pressurized by the hydrogen compressor (11), it is cooled after absorbing heat on the heat-taking side of the first-stage hydrogen heat exchanger (12) and the heat-taking side of the first hydrogen-helium interactive heat exchanger (A1), and is expanded and cooled after reducing pressure by the hydrogen hydraulic turbine expander (13) to form a liquid hydrogen product, which is then stored in a liquid hydrogen tank (14); The low-temperature gaseous hydrogen in the liquid hydrogen tank (14) flows out from the gas phase outlet, and is heated up after passing through the first heat release side of the first hydrogen-helium interchanging heat exchanger (A1) and the heat release side of the hydrogen first-stage heat exchanger (12) to release heat, and then becomes room-temperature gaseous hydrogen. The room-temperature gaseous hydrogen is mixed with the helium raw material and then reintroduced to form a circulating liquefaction of the hydrogen gas.

8. The hydrogen-helium liquefaction method according to claim 7, characterized in that: The liquefaction of the helium comprises the following steps: Opening the first on-off valve (35) and the second on-off valve (36); Introducing helium into the air inlet of the helium compressor (21); The helium is first pressurized by a helium compressor (21), and then passes through the heat-taking side of the first-stage helium heat exchanger (22) to absorb heat and cool down, and then is divided into two parts. One part of the helium passes through the heat-taking side of the second-stage helium heat exchanger (31), the first heat-taking side of the second hydrogen-helium interactive heat exchanger (A2), and the heat-taking side of the fourth-stage helium heat exchanger (32) in sequence to absorb heat and cool down, and then passes through the helium hydraulic turbine expander (33) to reduce pressure, expand and cool down, to form a liquid helium product, which is stored in a liquid helium tank (34); the other part of the helium passes through the helium expander (23) to reduce pressure, expand and cool down, and then is mixed with the liquid helium in the liquid helium tank (34). The low-temperature helium gas discharged is sequentially passed through the heat release side of the fourth-stage helium heat exchanger (32), the first heat collection side of the second hydrogen-helium interactive heat exchanger (A2), and the heat collection side of the second-stage helium heat exchanger (31) to release heat and then be heated to obtain normal-temperature gas helium, which is first mixed, and then passed through the second heat release side of the first hydrogen-helium interactive heat exchanger (A1) and the heat release side of the first-stage helium heat exchanger (22) to release heat and then be heated to become normal-temperature helium gas. The normal-temperature helium gas is mixed with the helium raw material again and then introduced into the air inlet of the helium compressor (21) again, thereby forming a circulating liquefaction of the helium gas.

9. The hydrogen-helium liquefaction method according to claim 8, characterized in that: During the circulation and liquefaction process of the helium gas, opening the third switch valve (41) and the fourth switch valve (42); The liquid hydrogen in the liquid hydrogen tank (14) flows out from the liquid phase outlet, absorbs heat on the second heat extraction side of the second hydrogen-helium interactive heat exchanger (A2), and then cools down, mixes with the low-temperature gaseous hydrogen flowing out from the gas phase outlet of the liquid hydrogen tank (14), and enters the inlet of the first heat release side of the first hydrogen-helium interactive heat exchanger (A1) together.

10. The hydrogen-helium liquefaction method according to claim 9, characterized in that: When only hydrogen is introduced into the air inlet of the hydrogen compressor (11) and helium is not introduced into the air inlet of the helium compressor (21), or when only hydrogen is introduced into the air inlet of the helium compressor (21) and helium is not introduced into the air inlet of the hydrogen compressor (11), the process of liquefying the hydrogen or the process of liquefying the helium is performed separately; When hydrogen and helium are introduced into the air inlets of the hydrogen compressor (11) and the helium compressor (21) respectively at the same time, the liquefaction process of the hydrogen and the liquefaction process of the helium are carried out simultaneously.

Images