CN114963688A - Hydrogen liquefaction system adopting low-temperature turbine compression cycle - Google Patents

Hydrogen liquefaction system adopting low-temperature turbine compression cycle Download PDF

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Publication number
CN114963688A
CN114963688A CN202110404058.2A CN202110404058A CN114963688A CN 114963688 A CN114963688 A CN 114963688A CN 202110404058 A CN202110404058 A CN 202110404058A CN 114963688 A CN114963688 A CN 114963688A
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hydrogen
low
temperature
heat exchanger
stage
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CN202110404058.2A
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CN114963688B (en
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吴英哲
姜伟
钱佚
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Henan Zhongke Qingneng Technology Co ltd
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Henan Zhongke Qingneng Technology Co ltd
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    • F25J2250/02—Bath type boiler-condenser using thermo-siphon effect, e.g. with natural or forced circulation or pool boiling, i.e. core-in-kettle heat exchanger
    • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F25—REFRIGERATION OR COOLING; COMBINED HEATING AND REFRIGERATION SYSTEMS; HEAT PUMP SYSTEMS; MANUFACTURE OR STORAGE OF ICE; LIQUEFACTION SOLIDIFICATION OF GASES
    • F25J—LIQUEFACTION, SOLIDIFICATION OR SEPARATION OF GASES OR GASEOUS OR LIQUEFIED GASEOUS MIXTURES BY PRESSURE AND COLD TREATMENT OR BY BRINGING THEM INTO THE SUPERCRITICAL STATE
    • F25J2270/00—Refrigeration techniques used
    • F25J2270/14—External refrigeration with work-producing gas expansion loop
    • F25J2270/16—External refrigeration with work-producing gas expansion loop with mutliple gas expansion loops of the same refrigerant
    • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F25—REFRIGERATION OR COOLING; COMBINED HEATING AND REFRIGERATION SYSTEMS; HEAT PUMP SYSTEMS; MANUFACTURE OR STORAGE OF ICE; LIQUEFACTION SOLIDIFICATION OF GASES
    • F25J—LIQUEFACTION, SOLIDIFICATION OR SEPARATION OF GASES OR GASEOUS OR LIQUEFIED GASEOUS MIXTURES BY PRESSURE AND COLD TREATMENT OR BY BRINGING THEM INTO THE SUPERCRITICAL STATE
    • F25J2270/00—Refrigeration techniques used
    • F25J2270/90—External refrigeration, e.g. conventional closed-loop mechanical refrigeration unit using Freon or NH3, unspecified external refrigeration
    • F25J2270/908—External refrigeration, e.g. conventional closed-loop mechanical refrigeration unit using Freon or NH3, unspecified external refrigeration by regenerative chillers, i.e. oscillating or dynamic systems, e.g. Stirling refrigerator, thermoelectric ("Peltier") or magnetic refrigeration

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  • Physics & Mathematics (AREA)
  • Mechanical Engineering (AREA)
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  • Separation By Low-Temperature Treatments (AREA)

Abstract

The invention provides a hydrogen liquefaction system adopting low-temperature turbine compression circulation, wherein a low-temperature hydrogen return branch is arranged, a shaft-driven compressor is arranged on a return branch pipeline, and a driving shaft of the compressor is connected with an output shaft of a turboexpander in a main refrigeration system, so that the expansion work generated when the turboexpander performs expansion refrigeration on a refrigeration working medium is recycled, and the total energy consumption of the hydrogen liquefaction system is reduced; and further refrigerating the hydrogen main flow flowing into each stage of the ortho-para hydrogen catalytic reactor by the low-temperature hydrogen in the reflux branch. Meanwhile, a mixing ejector is arranged to realize the mixing of the hydrogen in the backflow branch and the hydrogen flowing out from the hydrogen source; the bypass ejector is arranged to realize backflow of saturated hydrogen in the liquid hydrogen storage tank, pressure in the liquid hydrogen storage tank is reduced, cold quantity of the flowing saturated hydrogen is recycled, energy consumption is further reduced, the process of overpressure discharge of the saturated hydrogen in the liquid hydrogen storage tank is avoided, working efficiency is improved, and cost is reduced.

Description

Hydrogen liquefaction system adopting low-temperature turbine compression cycle
Technical Field
The invention belongs to the technical field of low-temperature engineering equipment, and particularly relates to a hydrogen liquefaction system adopting low-temperature turbine compression circulation.
Background
In recent years, with strategic implementation and structural adjustment of clean energy in China, development and utilization of various new energy sources attract a lot of attention. Among them, hydrogen energy is one of the important long-term solutions to the current energy problem as an efficient and clean energy source. How to safely and effectively store and transport hydrogen energy is a key technical challenge for large-scale application of hydrogen energy. The hydrogen storage technology with the most extensive application and the most mature technology is used at present. However, with the increasing maturity of cryogenic cooling, heat insulation and vacuum technologies, the storage and transportation mode of low-temperature liquid hydrogen has higher storage density and lower operation pressure, reduces the energy consumption and space cost of unit mass transportation, and is expected to become an effective mode for long-distance transportation and large-scale storage of hydrogen.
The liquefaction of hydrogen is the most critical link in the industrial chain of liquid hydrogen storage and transportation, and has the characteristics of complex technical process, high energy consumption and high investment cost. Over the past decades, much research has been done to improve the efficiency of hydrogen liquefaction. The efficiency of hydrogen liquefaction is improved, the operation cost of the hydrogen liquefaction equipment can be effectively reduced, and the equipment investment cost can also be indirectly reduced.
The hydrogen liquefaction system in the prior art generally comprises a main refrigeration system, a liquefaction system and a low-temperature heat exchanger group, wherein the main refrigeration system is provided with a compressor and an expansion machine, and exchanges heat with hydrogen in the liquefaction system through the low-temperature heat exchanger group to refrigerate the hydrogen so as to finally form a liquid hydrogen product. The compressor is used for compressing the high pressure of a refrigerating working medium in a compression stroke and providing the high pressure working medium for a circulation pipeline of the main refrigerating system, and the expander is used for expanding and refrigerating the high pressure working medium and providing cold energy for the liquefying system. In the low-temperature heat exchanger group, each low-temperature heat exchanger is provided with an orthosteric hydrogen catalytic reactor (an isothermal continuous reactor can be adopted, and an adiabatic step reactor can be also adopted) so as to catalyze hydrogen into equilibrium hydrogen at the current heat exchanger temperature. Raw material hydrogen provided by a hydrogen source sequentially passes through a normal-secondary hydrogen reactor in the multistage heat exchanger, finally enters a liquid hydrogen storage tank in a liquid state and flows out from a product outlet.
But of the currently operating hydrogen liquefaction plants
Figure BDA0003021536940000011
The efficiency is still low, and is only 20-30%. The main irreversible losses of the hydrogen liquefaction process mainly come from compressors, heat exchangers and expanders. The isothermal efficiency of a helium screw compressor and a hydrogen piston compressor adopted in the mainstream hydrogen liquefaction process at present is not very ideal, and is only about 40-50%.
When the process adopting helium or helium-neon mixed gas as a main refrigeration cycle working medium exchanges heat with a heat exchanger, a temperature region near a critical point of hydrogen has larger heat exchange temperature difference particularly; the process of using hydrogen as the main refrigeration cycle working medium has the problems of complex process, more flow channels, low hydrogen density, large resistance and the like, so that the efficiency of the heat exchanger part in the actual engineering is not ideal.
At present, the isentropic efficiency of a low-temperature turboexpander in a hydrogen liquefaction process can generally reach more than 70%, but the hydrogen molecular weight is small, so that the large-scale high-speed low-temperature hydrogen low-temperature turboexpander still has a plurality of technical challenges, such as bearing rigidity and stability of a large-scale turbine, high stress of a turbine tip blade and the like.
Disclosure of Invention
The invention provides a hydrogen liquefaction system with higher energy efficiency starting from the aspects of improving compression efficiency, recovering expansion work and optimizing process flow. Therefore, the invention adopts the following technical scheme:
the hydrogen liquefaction system adopting low-temperature turbine compression circulation comprises a liquefaction system, a low-temperature heat exchanger group, a precooling system and a main refrigeration system for providing a cold source for the low-temperature heat exchanger group;
the liquefaction system comprises an ortho-para hydrogen catalytic reactor I and n-grade ortho-para hydrogen catalytic reactors sequentially connected in series with the ortho-para hydrogen catalytic reactor I; the low-temperature heat exchanger group comprises n-grade low-temperature heat exchangers for respectively refrigerating and exchanging heat of n-grade ortho-para hydrogen catalytic reactors; the precooling system provides precooling cold energy for the para-hydrogen catalytic reactor I and the main refrigerating system respectively;
the mixing ejector, a shaft-driven compressor and a throttling element are further included;
the main refrigerating system comprises at least one turbine expansion machine, and an output shaft of the turbine expansion machine is in transmission connection with the shaft-driven compressor;
a return branch is led out from a pipeline at the discharge port of the n-1 stage of the orthohydrogen catalytic reactor, and working media in the return branch are sequentially throttled by a throttling element, subjected to heat exchange by at least one low-temperature heat exchanger, compressed by a shaft-driven compressor and precooled by a precooling system and then enter the mixing ejector as high-pressure fluid; or working medium of the return branch sequentially passes through throttling of the throttling element and heat exchange of at least one low-temperature heat exchanger to serve as low-pressure fluid to enter the mixer;
when the working medium is used as high-pressure fluid, the material at the outlet of the para-hydrogen catalytic reactor I is used as low-pressure fluid to enter the mixing ejector, and the mixed fluid sequentially enters the n-stage para-hydrogen catalytic reactor; when the working medium is used as a low-pressure fluid, the material at the outlet of the para-hydrogen catalytic reactor I is used as a high-pressure fluid and enters the mixing ejector, and the mixed material sequentially enters the n-stage para-hydrogen catalytic reactor after being compressed by the shaft-driven compressor and precooled by the precooling system.
The above-mentioned para-hydrogen catalytic reactor and corresponding low-temperature heat exchanger can adopt integrated structure, also can adopt mutually independent structure. The former belongs to an isothermal continuous reactor, which essentially fills a catalyst in a low-temperature heat exchanger flow channel, and the reactor is a heat exchanger, namely completes the catalytic reaction of the positive and the secondary hydrogen and simultaneously realizes the cooling of the inflow hydrogen; the latter is an adiabatic step reactor, essentially, a single adiabatic container is filled with a catalyst, hydrogen firstly enters the reactor for catalytic reaction after being cooled by a corresponding low-temperature heat exchanger, the temperature is raised, and then the hydrogen is cooled by a subsequent low-temperature heat exchanger; the isothermal continuous reactor has higher efficiency and more compact structure than an adiabatic step reactor; however, the former is difficult to manufacture, the latter is simple to process and manufacture, and both structures can be applied to the technical scheme of the invention.
In the technical scheme, the pre-cooling system pre-cools the hydrogen passing through the para-hydrogen catalytic reactor I and the working medium in the main refrigeration system, and the pre-cooling temperature is generally 70-120K. The shaft driven compressor is a low temperature turbine compressor. The turbo expander is a low-temperature turbo expander.
Among the above-mentioned technical scheme, low temperature turboexpander can set up a plurality ofly, and the axle drive compressor also can set up one or more as required, and the output shaft of a low temperature turboexpander is connected to the transmission shaft of every axle drive compressor to the work of expansion of fully retrieving low temperature turboexpander improves energy utilization.
Preferably, the liquefaction system further comprises a hydrogen low-temperature purification system connected with the inlet of the para-hydrogen catalytic reactor I, and the hydrogen low-temperature purification system is used for removing impurities and purifying hydrogen entering the para-hydrogen catalytic reactor I.
The hydrogen low-temperature purification system is a low-temperature purification adsorber. The hydrogen low-temperature purification system can be a single low-temperature purification adsorber, or can be two or more low-temperature purification adsorbers arranged in parallel.
Preferably, the hydrogen low-temperature purification system comprises two low-temperature purification adsorbers which are switched by a valve and alternately connected into a pipeline, the two low-temperature purification adsorbers are connected in parallel to form a typical temperature swing adsorption device, when one of the low-temperature purification adsorbers is connected into the pipeline, the low-temperature purification adsorber which is not connected into the pipeline is purged and heated by clean inert hot gas to realize regeneration, and the working efficiency of the hydrogen low-temperature purification system is improved.
Preferably, the low-temperature heat exchanger group is a heat exchanger group consisting of a plate-fin type or a wound tube type multi-path convection type heat exchanger.
Preferably, the main refrigeration system comprises a compression system, a main refrigeration working medium low-temperature purification and filtration system and a low-temperature stage. The compression system, the precooling system, the main refrigerating medium low-temperature purification and filtration system and the low-temperature stage are sequentially connected through pipelines to form a loop. The circulating pipeline of the low-temperature stage at least comprises a low-temperature turbo expander, and the main refrigeration working medium is expanded and refrigerated through the low-temperature turbo expander. The low-temperature stage is coupled with the liquefaction system through the low-temperature heat exchanger group to cool the hydrogen in the liquefaction system, and the lowest cooling temperature is about 20K.
Preferably, the main refrigerant low-temperature purification and filtration system adopts a low-temperature adsorption filter to purify and filter the refrigerant.
As a further preference, the compression system comprises at least one working medium compressor, at least one water cooler and an oil removal system. The working medium compressor is used for compressing working medium circulated back in the main refrigerating system into high-pressure gas, the compression heat is taken away by the water cooler, oil gas impurities in the high-pressure working medium are removed by the oil removing system, and then the high-pressure working medium enters the precooling system for precooling.
Preferably, the main refrigeration system is a brayton cycle refrigeration system or a claude cycle refrigeration system according to the capacity of the hydrogen liquefaction system.
The Brayton cycle refrigeration system adopts helium or a helium-neon mixture as a working medium, the working medium is compressed by a compression system, and is precooled to 70-120K by a precooling system, then further enters an n-stage low-temperature heat exchanger in sequence, is cooled to about 40K by a returned low-temperature working medium, and further enters a one-stage or multi-stage low-temperature turbine expander for expansion refrigeration, the temperature of the working medium is reduced to below 20K, and then the working medium is returned to the n-stage low-temperature heat exchanger in sequence in a reverse direction (from the nth low-temperature heat exchanger to the first-stage low-temperature heat exchanger), so that an inflowing high-temperature working medium and hydrogen of a liquefaction system are cooled. The technical scheme avoids hydrogen-related equipment with higher technical difficulty, such as a high-pressure hydrogen pipeline, a hydrogen compressor, a hydrogen low-temperature turboexpander and the like, has simpler process flow, and is more suitable for medium and small hydrogen liquefying devices with the capacity of below 5 tons/day.
The Claude cycle refrigeration system adopts hydrogen as a working medium, the working medium is compressed by a compression system, the working medium is firstly precooled to 70-120K by a precooling system, then further enters a multistage low-temperature heat exchanger in sequence and is cooled to about 40K by a returned low-temperature working medium, one part of hydrogen is expanded and refrigerated by a hydrogen expander (a low-temperature turbine expander), then returns to the multistage low-temperature heat exchanger in sequence in a reverse direction to cool the inflowing hydrogen, the other part of hydrogen continues to enter a low-temperature heat exchanger with lower temperature and finally performs isenthalpic throttling by a throttling device to generate cold energy, and then returns to n-stage low-temperature heat exchangers in sequence in a reverse direction (from the nth low-temperature heat exchanger to the first-stage low-temperature heat exchanger) to cool the inflowing hydrogen. The claude cycle has a variety of variations depending on the different temperature levels and series arrangements of the low temperature turboexpander and the series arrangement of the compression system. The technical scheme has a complex process flow, but the hydrogen working medium has high heat exchange performance and can obtain high efficiency in the low-temperature heat exchanger, so that the energy efficiency is better than that of a Brayton cycle refrigeration system adopting helium or a helium-neon mixed working medium, and the hydrogen liquefying system is more suitable for medium and large hydrogen liquefying devices with the capacity of more than 5 tons/day.
Preferably, the throttling element is an expander, a throttle valve or a bypass ejector.
As a further preference, the liquefaction system also comprises a liquid hydrogen storage tank connected with the n-th stage parahydrogen catalytic reactor through a pipeline;
the throttling element is a bypass ejector, and the backflow branch is connected with a high-pressure inlet of the bypass ejector; and a gas phase outlet of the liquid hydrogen storage tank is connected with a low-pressure inlet of the bypass ejector through a gas phase loop.
As a further preferred scheme, a pipeline is led out from the bottom of the liquid hydrogen storage tank to a liquid hydrogen product outlet for outputting liquid hydrogen.
As a further preferable scheme, the gas phase loop is connected with the low-pressure inlet of the bypass ejector after heat exchange through the nth-stage low-temperature heat exchanger.
In the scheme, gaseous hydrogen in the liquid hydrogen storage tank flows out from the gas phase outlet to enter the bypass ejector after being subjected to heat exchange by the nth-stage low-temperature heat exchanger, so that the pressure in the liquid hydrogen storage tank can be reduced, and the cold energy of the gaseous hydrogen can be recycled to further cool the hydrogen in the nth-stage orthohydrogen catalytic reactor.
Furthermore, the working medium at the outlet of the bypass ejector exchanges heat with the n-1 st-stage low-temperature heat exchangers in sequence. The cold energy of the reflux working medium is fully utilized.
As a further preferred scheme, the gas phase loop is directly connected with the low-pressure inlet of the bypass ejector.
In the scheme, gaseous hydrogen in the liquid hydrogen storage tank flows out from the gas phase outlet and is mixed with the returned working medium in the bypass ejector, and then the gaseous hydrogen is subjected to heat exchange through the nth-stage low-temperature heat exchanger, so that the pressure in the liquid hydrogen storage tank can be reduced, and the cold energy of the gaseous hydrogen can be recycled to further cool the hydrogen in the nth-stage normal-para hydrogen catalytic reactor.
Furthermore, the working medium at the outlet of the bypass ejector sequentially passes through the nth-1-stage low-temperature heat exchangers for heat exchange.
Preferably, throttling devices are arranged on pipelines of the liquid hydrogen storage tank and the nth-stage low-temperature heat exchanger, so that hydrogen at the outlet of the nth-stage low-temperature heat exchanger can be further subjected to pressure reduction and refrigeration. Preferably, the throttling means is a throttle valve.
Preferably, a compensation driving motor is provided on a shaft connecting the expander and the compressor. The compensation driving motor is used for providing additional power to drive the low-temperature turbine compressor so as to obtain enough compression driving force.
Preferably, the compensation driving motor is a high-speed superconducting motor to reduce motor loss and reduce motor size.
Preferably, the shaft driven compressor comprises a cryogenic turbine compressor.
Preferably, the working medium in the reflux branch exchanges heat with the n-1 st low-temperature heat exchangers in sequence, and the cooling and refrigerating efficiency is further improved.
Preferably, the precooling system comprises a precooling heat exchanger and a cooling system for providing a cold source for the precooling heat exchanger, the cooling system is coupled with the main refrigerating system and the liquefying system through the precooling heat exchanger, and the precooling heat exchanger respectively provides cold for the para-hydrogen catalytic reactor I and the main refrigerating system.
According to different conditions of the site where the hydrogen liquefaction system is located, as further optimization, the cold supply system is an open type low-temperature frozen liquid precooling system or a closed type low-temperature refrigeration precooling system. The open type low-temperature frozen liquid precooling system adopts liquid nitrogen or liquefied natural gas as a cold source working medium, the former is particularly suitable for the situation that stable and cheap liquid nitrogen can be obtained on site, and for example, a nearby air separation device can provide stable and cheap liquid nitrogen resources; the latter is especially suitable for occasions such as liquefied natural gas ports and the like which need to recover the liquefied natural gas vaporization cold energy.
The closed low-temperature refrigeration precooling system is a turbine Brayton cycle refrigeration system, a self-cascade mixed working medium refrigeration system or a regenerative refrigeration system, and is suitable for scenes that the electricity price is low or low-temperature liquids such as liquid nitrogen, liquefied natural gas and the like are not easily obtained on site.
Preferably, the pre-cooling heat exchanger is a plate-fin or pipe-wound multi-convection heat exchanger.
Different from the traditional hydrogen liquefaction device, the hydrogen liquefaction system of the invention adopts a refrigeration liquefaction cycle of low-temperature compression, and the basic idea is as follows:
1. compressing a circulating hydrogen flow (backflow hydrogen, namely working medium in a backflow branch) by using a low-temperature turbine compressor operating at a precooling temperature (70-120K), and taking away compression heat by using a precooling system;
or the circulating hydrogen flow and the raw material hydrogen flow are mixed in the mixing ejector to form a main hydrogen flow, and then the main hydrogen flow enters the low-temperature turbine compressor for compression: an orthohydrogen catalytic reactor I positioned on the precooling heat exchanger is connected with a high-pressure inlet of the mixing ejector, an outlet of the mixing ejector is connected with a low-pressure inlet of the low-temperature turbine compressor, and a backflow circulating hydrogen flow outlet of a low-temperature heat exchanger (a first-stage low-temperature heat exchanger) with the highest temperature is connected with a low-pressure inlet of the mixing ejector.
2. The low-temperature turbine compressor is driven by expansion work generated by a low-temperature turbine expander in the main refrigeration system;
3. mixing the circulating hydrogen flow and the raw material hydrogen flow by adopting a mixing ejector to form a main hydrogen flow;
4. before a main hydrogen flow enters a low-temperature heat exchanger (nth-stage low-temperature heat exchanger) with the lowest temperature, the main hydrogen flow is divided into a circulating hydrogen flow and a liquefied hydrogen flow:
4.1, circulating hydrogen flows enter a bypass ejector, on one hand, the circulating hydrogen flows are used for pumping and recovering low-pressure saturated gaseous hydrogen from the top of a liquid hydrogen storage tank, on the other hand, the hydrogen is subjected to isenthalpic throttling to generate a refrigeration effect, and the mixed and cooled hydrogen sequentially returns to low-temperature heat exchangers of all stages (from an nth-stage low-temperature heat exchanger to a first-stage low-temperature heat exchanger) to cool the inflowing hydrogen;
or the saturated hydrogen from the liquid hydrogen storage tank firstly exchanges heat through the nth-stage low-temperature heat exchanger, then is mixed with the circulating hydrogen flow in the bypass ejector, and then sequentially passes through the (n-1) th-stage low-temperature heat exchanger to the first-stage low-temperature heat exchanger: and a gas phase pipeline (a gas phase loop) led out from the top of the liquid hydrogen storage tank is connected with a low-pressure inlet of the bypass ejector, and an outlet of the bypass ejector is connected with the n-1-level low-temperature heat exchanger.
4.2, the liquefied hydrogen flow enters an orthohydrogen catalytic reactor in the last stage of heat exchanger (the nth stage of low-temperature heat exchanger for heat exchange) to be cooled, and then is subjected to isenthalpic throttling through a throttling device to realize liquefaction and enters a liquid hydrogen storage tank.
The invention provides a hydrogen liquefaction system adopting low-temperature turbine compression circulation, wherein a low-temperature hydrogen return branch is arranged, a shaft driving compressor is arranged on a return branch pipeline, and a driving shaft of the compressor is connected with an output shaft of a turbine expander in a main refrigeration system, so that the expansion work generated when the turbine expander performs expansion refrigeration on a refrigeration working medium is recycled, and the total energy consumption of the hydrogen liquefaction system is reduced; and further refrigerating the hydrogen main flow flowing into each stage of the ortho-para hydrogen catalytic reactor by the low-temperature hydrogen in the reflux branch. Meanwhile, a mixing ejector is arranged to realize the mixing of the hydrogen in the backflow branch and the hydrogen flowing out from the hydrogen source; the bypass ejector is arranged to realize backflow of saturated hydrogen in the liquid hydrogen storage tank, pressure in the liquid hydrogen storage tank is reduced, cold quantity of the flowing saturated hydrogen is recycled, energy consumption is further reduced, the process of overpressure discharge of the saturated hydrogen in the liquid hydrogen storage tank is avoided, working efficiency is improved, and cost is reduced.
Compared with the prior art, the invention has the beneficial effects that:
the hydrogen liquefaction system adopting the low-temperature turbine compression cycle fully utilizes the expansion work of the main refrigeration cycle turboexpander to drive the liquefaction system to form the self-contained refrigeration cycle, and has higher energy efficiency. According to the low-temperature turbine compression cycle process, hydrogen is compressed at a low temperature of 77-100K, and the hydrogen has higher efficiency than the hydrogen compressed at room temperature due to the fact that the hydrogen has higher density and lower adiabatic compression coefficient at the low temperature.
Compared with the traditional Joule-Thomson circulating refrigeration process flow, the process has the advantages that the return air pressure of the compressor is higher under the condition of the same throttling expansion pressure, the power consumption of the compressor is reduced, and the energy efficiency is higher; compared with a bypass process adopting a turbine expander, the method avoids using a complex and expensive low-temperature hydrogen expander, has simple process flow and can also recover the vapor-phase hydrogen of the liquid hydrogen storage tank.
Drawings
FIG. 1 is a schematic diagram of a first embodiment of a hydrogen liquefaction plant employing a cryogenic turbine compression cycle in accordance with the present invention;
FIG. 2 is a schematic diagram of a second embodiment of a hydrogen liquefaction plant employing a cryogenic turbine compression cycle in accordance with the present invention;
FIG. 3 is a schematic diagram of a third embodiment of a hydrogen liquefaction plant employing a cryogenic turbine compression cycle in accordance with the present invention;
FIG. 4 is a schematic diagram of a fourth embodiment of a hydrogen liquefaction plant employing a cryogenic turbine compression cycle in accordance with the present invention, wherein the pre-cooling system employs an open liquid nitrogen pre-cooling system and the main refrigeration system employs a helium Brayton cycle refrigeration system;
fig. 5 is a schematic diagram of a fifth embodiment of the hydrogen liquefaction plant using a low-temperature turbine compression cycle of the present invention, wherein the precooling system employs a closed turbine brayton refrigeration system and the main refrigeration system employs a hydrogen claude cycle refrigeration system.
The corresponding relation between the marks and the part names in the drawings is as follows:
100. the system comprises a cooling system, 101, a liquid nitrogen storage tank, 102, a liquid nitrogen source, 103, low-temperature turbo compressors I, 104, a water cooler, 105, low-temperature turbo expanders I and 106, a high-speed motor, 200, a main refrigeration system, 210, a compression system, 211, a screw compressor, 212, a water cooler I and 213, a deoiling system, 214, a primary compressor, 215, a primary water cooler, 216, a secondary compressor, 217, a secondary water cooler, 220, a main refrigeration working medium low-temperature purification and filtration system, 221, a low-temperature adsorption filter, 230, a low-temperature stage, 231, a low-temperature turbo expander, 232, a primary low-temperature turbo expander, 233, a secondary low-temperature turbo expander, 234, a throttle valve, 300, a liquefaction system, 301, a hydrogen gas source, 302, a hydrogen low-temperature purification system, 302a, 302B, hydrogen low-temperature purification adsorbers B and 303, a normal-secondary hydrogen catalytic reactor I and II, 304. The system comprises a mixing ejector, 305, a low-temperature turbine compressor, 306, a compensation driving motor, 307, a first-stage normal-secondary hydrogen catalytic reactor, 308, an n-1-stage normal-secondary hydrogen catalytic reactor, 309, a bypass ejector, 310, an nth-stage normal-secondary hydrogen catalytic reactor, 311, a throttling device, 312, a liquid hydrogen storage tank, 313, a liquid hydrogen product outlet, 314, a second-stage normal-secondary hydrogen catalytic reactor, 315, a third-stage normal-secondary hydrogen catalytic reactor, 316, a throttling valve, 317, a fourth-stage normal-secondary hydrogen catalytic reactor, 318, a fifth-stage normal-secondary hydrogen catalytic reactor, 319, a sixth-stage normal-secondary hydrogen catalytic reactor, 400, a precooling heat exchanger, 500, a low-temperature heat exchanger bank, 501, a first-stage low-temperature heat exchanger, 502, an n-1-stage low-temperature heat exchanger, 503, an nth-stage low-temperature heat exchanger, 504, a second-stage low-temperature heat exchanger, 505, a third-stage low-temperature heat exchanger, 506, a fourth-stage low-temperature heat exchanger, a cold, 507. A fifth-stage low-temperature heat exchanger, 508, a sixth-stage low-temperature heat exchanger.
Detailed Description
In order to make the objects, technical solutions and advantages of the embodiments of the present invention clearer, the technical solutions of the present invention are described in further detail below with reference to the embodiments of the present invention and the accompanying drawings, but the described embodiments are some, not all, of the embodiments of the present invention. Other embodiments, which are not inventive by the person skilled in the art, are within the scope of protection of the present invention, based on the embodiments of the present invention.
Example 1:
as shown in fig. 1, the hydrogen liquefaction system using the low-temperature turbine compression cycle includes a cooling system 100, a main refrigeration system 200, a liquefaction system 300, a pre-cooling heat exchanger 400, and a low-temperature heat exchanger group 500. The cold supply system 100 is coupled with the main refrigeration system 200 and the liquefaction system 300 through the precooling heat exchanger 400, precools the working medium of the main refrigeration system 200 and the hydrogen of the liquefaction system 300, and the precooling temperature is generally about 70-120K.
The main refrigeration system 200 includes a compression system 210, a main refrigerant low temperature purification filtration system 220, and a low temperature stage 230. The compression system 210, the precooling heat exchanger 400, the main refrigerant low-temperature purification and filtration system 220 and the low-temperature stage 230 are sequentially connected through a pipeline to form a loop. The circulation pipeline of the low temperature stage 220 includes a low temperature turboexpander 231 (in this embodiment, a first low temperature turboexpander is selected), and the gas working medium is expanded and cooled by the low temperature turboexpander 231. The low-temperature stage 230 is coupled to the liquefaction system 300 through the low-temperature heat exchanger group 500, and cools the hydrogen in the liquefaction system 300, and the lowest precooling temperature is about 20K.
The liquefaction system 300 comprises a hydrogen gas source 301, a hydrogen low-temperature purification system 302, an orthohydrogen catalytic reactor I303, an n-stage orthohydrogen catalytic reactor, a mixing ejector 304, a low-temperature turbine compressor 305, a bypass ejector 309, a throttling device 311, a liquid hydrogen storage tank 312 and a compensation driving motor 306.
Wherein the hydrogen gas source 301, the precooling heat exchanger 400, the hydrogen low-temperature purification system 302, the para-hydrogen catalytic reactor I303 and the low-pressure inlet of the mixing ejector 304 are sequentially connected through a pipeline; an outlet of the mixing ejector 304, n-stage ortho-para-hydrogen catalytic reactors in each low-temperature heat exchanger group are sequentially connected with each other along a pipeline from high temperature to low temperature (from the first-stage ortho-para-hydrogen catalytic reactor 307 to the nth-stage ortho-para-hydrogen catalytic reactor 310), a throttling device 311 and a liquid hydrogen storage tank 312, wherein a pipeline (a backflow branch) is led out from a pipeline between the two ortho-para-hydrogen catalytic reactors (the nth-stage ortho-para-hydrogen catalytic reactor 310 and the nth-1 st-stage ortho-para-hydrogen catalytic reactor 308) with the lowest temperature and the second lowest temperature and is connected with a high-pressure inlet of the bypass ejector 309.
A pipeline is led out from the bottom of the liquid hydrogen storage tank 312 to a liquid hydrogen product outlet 313 for outputting liquid hydrogen, and a gas phase pipeline (a gas phase loop) is led out from the top of the liquid hydrogen storage tank 312, returns to pass through the lowest-temperature low-temperature heat exchanger (the nth-stage low-temperature heat exchanger 503) and then is connected with a low-pressure inlet of the bypass ejector 309; the outlet of the bypass ejector 309 and the rest (the n-1 st-stage low-temperature heat exchanger 503 to the first-stage low-temperature heat exchanger 501) low-temperature heat exchangers are sequentially connected from low to high along with temperature, and then are connected with the low-pressure inlet of the low-temperature turbine compressor 305.
A high-pressure outlet of the low-temperature turbine compressor 305 is connected with a connector in the middle of the precooling heat exchanger 400 through a pipeline, and is connected with a high-pressure inlet of the mixing ejector 304 after being precooled by the precooling heat exchanger 400; the low temperature turbo compressor 305 is mechanically coupled to the low temperature turbo expander 231 in the main refrigeration system 200 by a shaft, and the shaft is provided with a compensation driving motor 306, so that the expansion generated by the low temperature turbo expander 231 in the main refrigeration process flow is used for driving the low temperature turbo compressor 305, and the compensation driving motor 306 is used for providing additional power for driving the low temperature turbo compressor 305.
The working principle of implementing hydrogen liquefaction by adopting the embodiment is as follows:
the cold supply system 100 is coupled with the main refrigeration system 200 and the liquefaction system 300 through the precooling heat exchanger 400, precools the working medium of the main refrigeration system 200 and the hydrogen of the liquefaction system 300, and the precooling temperature is generally about 70-120K. A low-temperature working medium generated by the cold supply system 100 enters the cold end inlet of the pre-cooling heat exchanger 400, and the working medium of the main refrigeration system 200 and the hydrogen of the liquefaction system 300 are pre-cooled in the pre-cooling heat exchanger 400; the working medium is reheated to about room temperature in the pre-cooling heat exchanger 400, leaves the hot end outlet of the pre-cooling heat exchanger 400, and then leaves the whole hydrogen liquefaction device (for an open low-temperature frozen liquid cooling system) or returns to the cooling system 100 (for a closed low-temperature refrigeration cooling system) according to the type of the cooling system 100.
The main refrigeration system 200 is coupled with the liquefaction system 300 through a pre-cooling heat exchanger 400 and a low-temperature heat exchanger group 500, and pre-cools the hydrogen gas of the liquefaction system 300, wherein the pre-cooling temperature is generally about 20K. After the working medium of the main refrigeration system 200 is compressed by the compression system 210 to become high pressure, the working medium enters the pre-cooling heat exchanger 400 and is pre-cooled to about 70-120K, and then further sequentially enters the low-temperature heat exchangers of all stages (sequentially enters from the first-stage low-temperature heat exchanger 501 to the nth-stage low-temperature heat exchanger 503) and is cooled by the returned cold working medium (the working medium of the main refrigeration system 200). During the period, the working medium is expanded by the low-temperature turbo expander 231 to generate a refrigeration effect, and finally, the low-pressure and low-temperature working medium returns to each stage of low-temperature heat exchangers in sequence (returns from the nth stage of low-temperature heat exchanger 503 to the first stage of low-temperature heat exchanger 501 in sequence) to cool the inflowing high-pressure and high-temperature working medium and the hydrogen of the liquefaction system 300.
In the liquefaction system 300, a raw material hydrogen stream from a hydrogen gas source 301 firstly enters a pre-cooling heat exchanger 400 for pre-cooling, and then sequentially passes through a hydrogen low-temperature purification system 302 and an ortho-para-hydrogen catalytic reactor I303 arranged in the pre-cooling heat exchanger 400, so that impurity gas and particulate matters in the hydrogen are removed, and a preliminary ortho-para-hydrogen catalytic reaction is completed, wherein the para-hydrogen content is close to an equilibrium state (for example, the pre-cooling temperature is 77.4K of liquid nitrogen, and the para-hydrogen content of the equilibrium hydrogen is 50.2%).
Then, a flow of the feed hydrogen (pressure p) feed ) Pumped into the low pressure inlet of the mixing eductor 304 and a high pressure recycle hydrogen stream (pressure p) entering the high pressure inlet of the mixing eductor 304 compressed by the low temperature turbo-compressor 305 and cooled by the pre-cooling heat exchanger 400 compr ) Mixing into a main flow of hydrogen (pressure p) main ) And exits the outlet of the mixing eductor 304. In the mixing ejector 304, p compr ＞p main ＞p feed The pressure of the raw hydrogen flow is controlled from p by utilizing the pressure potential energy of the high-pressure circulating hydrogen flow reed Is lifted to p main . The main flow of hydrogen further sequentially enters the normal-para hydrogen catalytic reactors in the low-temperature heat exchangers at all levels along the direction of decreasing temperature, is cooled to about 35K by the backflow working medium of the main refrigeration system 200 and the backflow cold hydrogen circulating flow, and simultaneously undergoes normal-para hydrogen reaction, and the content of para hydrogen reaches an equilibrium state.
Before entering the low-temperature heat exchanger (the N-stage low-temperature heat exchanger 503) with the lowest temperature, the main hydrogen flow is divided into two paths, one path is circulating hydrogen flow (backflow hydrogen branch), and the circulating hydrogen flow enters a high-pressure inlet of the bypass ejector 309; the other path is liquefied hydrogen flow, and the liquefied hydrogen flow further enters an nth-stage normal-para hydrogen catalytic reactor 310 in a low-temperature heat exchanger (nth-stage low-temperature heat exchanger 503) with the lowest temperature, is cooled to about 20-25K by a reflux working medium of the main refrigeration system 200 and low-temperature saturated hydrogen from a gas phase pipeline of the liquid hydrogen storage tank 312, and simultaneously undergoes normal-para hydrogen reaction to enable the content of the para hydrogen to reach more than 95%.
After leaving the nth-stage low-temperature heat exchanger 503, the liquefied hydrogen gas flow enters a throttling device 311 for isenthalpic throttling, so that the hydrogen gas is liquefied, and then enters a liquid hydrogen storage tank 312. In the liquid hydrogen storage tank 312, the liquid hydrogen at the bottom flows out from a liquid phase pipeline arranged at the bottom of the liquid hydrogen storage tank 312 as a product, the saturated hydrogen at the top returns through a gas phase pipeline arranged at the top of the liquid hydrogen storage tank 312, enters the nth-stage low-temperature heat exchanger 503 to pre-cool the inflow liquefied hydrogen gas stream, and then enters the low-pressure inlet of the bypass ejector 309.
In the bypass eductor 309, the returning hydrogen is branched (pressure p) main ) With a saturated hydrogen stream (pressure p) sat Generally 1 to 2bar) to form a refluxing hydrogen recycle stream (pressure p) return ) Wherein p is main ＞p return ＞p sat The low pressure saturated hydrogen vapor is pumped from the liquid hydrogen tank 312 (pressure p from the main flow of hydrogen) using the pressure potential of the loop hydrogen branch from the main flow of hydrogen main Is lifted to p sat ). The returned hydrogen circulation flow sequentially enters the low-temperature heat exchangers of all stages along the direction of increasing temperature (sequentially returns from the nth-stage low-temperature heat exchanger 503 to the first-stage low-temperature heat exchanger 501), cools the inflow hydrogen main flow, and finally enters the low-temperature turbine compressor 305 to be compressed to high pressure (with the pressure being p) compr )。
Example 2:
as shown in fig. 2, the hydrogen liquefaction system using the low-temperature turbo-compression cycle is different from embodiment 1 in that:
an ortho-para hydrogen catalytic reactor I303 and a mixing eductor positioned in the precooling heat exchanger 400The high-pressure inlet of the mixer 304 is connected, the outlet of the mixing ejector 304 is connected with the low-pressure inlet of the low-temperature turbine compressor 305, and the backflow hydrogen circulation outlet of the low-temperature heat exchanger (the first-stage low-temperature heat exchanger 501) with the highest temperature is connected with the low-pressure inlet of the mixing ejector 304. In this example, a hydrogen recycle stream (pressure p) is returned return ) And a feed hydrogen stream (pressure p) feed ) The main flow of hydrogen (pressure p) is formed after mixing in the mixing ejector 304 main ) Then enters a low-temperature turbine compressor 305 to be compressed to high pressure (the pressure is p) compr )。
In the mixing eductor 304 of this embodiment, p feed ＞p main ＞p return The pressure potential of the feed hydrogen stream is used to recycle the returning lower pressure hydrogen stream from p return Is lifted to p main . This embodiment is suitable for the case where the pressure of the hydrogen supplied from the hydrogen source 301 is higher than the pressure of the hydrogen recycle stream flowing back.
Example 3:
as shown in fig. 3, the hydrogen liquefaction system using the low-temperature turbine compression cycle is different from that of example 1 in that:
a gas phase pipeline (a gas phase loop) led out from the top of the liquid hydrogen storage tank 312 is connected with a low-pressure inlet of the bypass ejector 309, and an outlet of the bypass ejector 309 is connected with a low-temperature heat exchanger (the nth-stage low-temperature heat exchanger 503) with the lowest temperature.
In this embodiment, saturated hydrogen gas (pressure p) from the liquid hydrogen storage tank 312 sat ) Is contacted with the circulating hydrogen stream (return hydrogen branch) (pressure p) in a bypass eductor 309 main ) Mixing and throttling and expanding to lower pressure to form a backflow hydrogen circulating flow (the pressure is p) return ) And then enters a cryogenic heat exchanger with the lowest temperature (the nth-stage cryogenic heat exchanger 503) to cool the inflowing liquefied hydrogen gas flow.
In the bypass eductor 309 of this embodiment, p main ＞p return ＞p sat The low pressure saturated hydrogen is pumped from the liquid hydrogen tank 312 (pressure p from the main stream of hydrogen) using the pressure potential of the circulating hydrogen stream main Is lifted to p sat )。
Example 4:
as shown in fig. 4, a hydrogen liquefaction system employing a cryogenic turbine compression cycle, liquid nitrogen pre-cooling, and helium brayton cycle is illustrated in more detail and includes a cooling supply system 100, a main refrigeration system 200, a liquefaction system 300, a pre-cooling heat exchanger 400, and a cryogenic heat exchanger.
The cooling system 100 includes a liquid nitrogen source 102 and a liquid nitrogen storage tank 101. The main refrigeration system 200 includes a screw compressor 211 (working medium compressor), a water cooler I212, a deoiling system 213, a low-temperature adsorption filter 221, a first-stage low-temperature turboexpander 232, and a second-stage low-temperature turboexpander 233. The liquefaction system 300 comprises a hydrogen gas source 301, a hydrogen low-temperature purification adsorber A302a, a hydrogen low-temperature purification adsorber B302B, an ortho-para-hydrogen catalytic reactor I303, a mixing ejector 304, a first stage ortho-para-hydrogen catalytic reactor 307, a second stage ortho-para-hydrogen catalytic reactor 314, a third stage ortho-para-hydrogen catalytic reactor 315, a throttle valve 316, a liquid hydrogen storage tank 312, a liquid hydrogen product outlet 313, a bypass ejector 309, a low-temperature turbine compressor 305 and a compensation drive motor 306. The low temperature heat exchanger group 500 comprises three convective heat exchangers with high to low temperatures: a first stage cryogenic heat exchanger 501, a second stage cryogenic heat exchanger 504 and a third stage cryogenic heat exchanger 505.
The components in the cooling system 100 are connected in the following order: a liquid nitrogen source 102 is connected with a liquid nitrogen storage tank 101, a liquid phase pipeline led out from the bottom of the liquid nitrogen storage tank 101 is connected with a cold end inlet of a pre-cooling heat exchanger 400, then a pipeline led out from the middle of the pre-cooling heat exchanger 400 is connected with the top of the liquid nitrogen storage tank 101, another gas phase pipeline at the top of the liquid nitrogen storage tank 101 is connected with an inlet in the middle of the pre-cooling heat exchanger 400, cold nitrogen in the liquid nitrogen storage tank 101 is led into the pre-cooling heat exchanger 400, and finally the cold nitrogen is discharged from the hot end of the pre-cooling heat exchanger 400.
The working principle of the cooling system 100 is: supplementing liquid nitrogen into the liquid nitrogen storage tank 101 by the liquid nitrogen source 102, and keeping the liquid level in the liquid nitrogen storage tank 101 not lower than a set height; saturated liquid nitrogen led out from the liquid nitrogen storage tank 101 firstly enters the cold end of the precooling heat exchanger 400 to precool the working medium of the main refrigeration system 200 and the hydrogen of the liquefaction system 300, the liquid nitrogen is heated and evaporated to form saturated gas, the saturated gas leaves from the middle part of the precooling heat exchanger 400 and enters the gas phase space at the top of the liquid nitrogen storage tank 101 to form a typical self-pressurization flow; under the action of the self-pressurization process, saturated liquid nitrogen gas flows out from another gas phase outlet (gas phase pipeline) at the top of the liquid nitrogen storage tank 101, enters the middle part of the precooling heat exchanger 400 and continues to flow towards the hot end, precooling is provided for the working medium of the main refrigeration system 200 and the hydrogen of the liquefaction system 300, and finally the nitrogen gas is heated to about room temperature and leaves at the hot end of the precooling heat exchanger 400.
In this embodiment, the open-type low-temperature frozen liquid cooling system 100 using liquid nitrogen as a cold source working medium can provide a precooling temperature of about 77-100K according to the difference of the pressure of the liquid nitrogen storage tank 101.
The components in the main refrigeration system 200 are connected in the following order: the high-pressure outlet of the screw compressor 211, the water cooler 212, the oil removal system 213, the precooling heat exchanger 400, the low-temperature adsorption filter 221, the first-stage low-temperature heat exchanger 501, the first-stage low-temperature turbo expander 232, the second-stage low-temperature heat exchanger 504 and the second-stage low-temperature turbo expander 233 are sequentially connected, and the outlet pipeline of the second-stage low-temperature turbo expander 233 sequentially passes through the third-stage low-temperature heat exchanger 505, the second-stage low-temperature heat exchanger 504 and the first-stage low-temperature heat exchanger 501 from low temperature to high temperature and is finally connected with the low-pressure inlet of the screw compressor 211.
Wherein, the working medium in the main refrigeration system 200 is helium. The operating principle of the main refrigeration system 200 is: the helium working medium is compressed to high pressure by the screw compressor 211, the compression heat generated by compression is taken away by the water cooler 212 and cooled to about room temperature, and then the helium working medium enters the oil removal system 213 to remove most of oil gas impurities in the working medium; the high-pressure helium gas after compression, cooling and oil removal firstly enters a precooling heat exchanger 400 to be precooled to about 77-100K, and then residual particulate impurities solidified at low temperature are removed through a low-temperature adsorption filter 221; after leaving the low-temperature adsorption filter 221, helium enters the first-stage low-temperature heat exchanger 501 and is pre-cooled to about 40-50K by the returned cold helium, and then enters the first-stage low-temperature turbo expander 232 for expansion refrigeration, the temperature is reduced by about 5-10K, and the pressure is reduced to the medium pressure; the helium gas leaves the first-stage low-temperature turboexpander 232 and then enters the second-stage low-temperature heat exchanger 504 to be further pre-cooled to about 25-30K; then, the mixture enters a secondary low-temperature turbine expander 233 for expansion refrigeration, the temperature is reduced to about 17-20K, and the pressure is reduced to low pressure; then, the low-temperature and low-pressure helium gas reversely passes through the third-stage low-temperature heat exchanger 505, the second-stage low-temperature heat exchanger 504 and the first-stage low-temperature heat exchanger 501 in sequence to provide cold energy for the inflow helium gas and the hydrogen gas of the liquefaction system 300, and after passing through the precooling heat exchanger 400, the helium gas is reheated to about room temperature and finally returns to the low-pressure inlet of the compressor.
The components in liquefaction system 300 are connected in the following order: the hydrogen gas source 301 is connected with a hot end interface of the precooling heat exchanger 400, and the inflow raw material hydrogen is connected with the hydrogen low-temperature purification adsorber A302a and the hydrogen low-temperature purification adsorber B302B which are connected in parallel after leaving the cold end of the precooling heat exchanger 400. Here, the hydrogen low-temperature purification adsorber a302a and the hydrogen low-temperature purification adsorber B302B constitute a typical temperature swing adsorption device, the two adsorbers are switched by valves and alternately connected to the pipeline, and the adsorber which is not connected to the pipeline is purged and heated by clean inert hot gas to realize regeneration. The hydrogen low-temperature purification adsorber A302a and the hydrogen low-temperature purification adsorber B302B are connected in parallel and then are connected with an inlet in the middle of the precooling heat exchanger 400 through a pipeline, and then enter the normal-secondary hydrogen catalytic reactor I303 at the lower temperature end of the precooling heat exchanger 400. In this embodiment, all the para-hydrogen catalytic reactors (including the para-hydrogen catalytic reactor I303, the first stage para-hydrogen catalytic reactor 307, the second stage para-hydrogen catalytic reactor 314 and the third stage para-hydrogen catalytic reactor 315) are isothermal reactors coupled in a heat exchanger, that is, catalyst particles are filled in heat exchange channels of the heat exchanger, and the para-hydrogen catalytic reaction is realized while heat exchange is carried out.
Such isothermal reactors have a high reaction efficiency and low irreversible losses. The outlet at the low temperature end of the para-hydrogen catalytic reactor I303 is connected to the low pressure inlet of the mixing eductor 304. The outlet of the mixing eductor 304, the first stage ortho-para-hydrogen catalytic reactor 307, the second stage ortho-para-hydrogen catalytic reactor 314, and the third stage ortho-para-hydrogen catalytic reactor 315 are sequentially connected, and then connected to the liquid hydrogen storage tank 312 through a throttle valve 316.
The liquid phase pipeline at the bottom of the liquid hydrogen storage tank 312 is a liquid hydrogen product output port of the hydrogen liquefier, and the gas phase pipeline (gas phase loop) at the top of the liquid hydrogen storage tank 312 is led out to return to pass through the third-stage low-temperature heat exchanger 505 and then is connected with the low-pressure inlet of the bypass ejector 309. A pipeline (loop branch) branched from the pipeline between the second stage ortho-para hydrogen catalytic reactor 314 and the third stage ortho-para hydrogen catalytic reactor 315 is connected with the high-pressure inlet of the bypass ejector 309. The outlet of the bypass ejector 309, the second-stage low-temperature heat exchanger 504, and the third-stage low-temperature heat exchanger 505 are connected in sequence, and then connected to the low-pressure inlet of the low-temperature turbine compressor 305.
A high-pressure outlet of the low-temperature turbine compressor 305 is connected with a connector in the middle of the precooling heat exchanger 400 through a pipeline, and is finally connected with a high-pressure inlet of the mixing ejector 304 after being precooled by the precooling heat exchanger 400; the low temperature turbine compressor 305 is mechanically coupled to the first stage low temperature turbine expander 232 of the main refrigeration system 200 by a shaft, and the expansion produced by the first stage low temperature turbine expander 232 of the main refrigeration process is used to drive the low temperature turbine compressor 305. A supplemental drive motor 306 is provided on the shaft of the cryogenic turbo compressor 305 mechanically coupled to the first stage cryogenic turbo expander 232 in the main refrigeration system 200 to provide additional power to drive the cryogenic turbo compressor 305. In this embodiment, the operation principle of the liquefaction system 300 is the same as that of the liquefaction system 300 in embodiment 1.
Example 5:
as shown in fig. 5, a hydrogen liquefaction system using a low-temperature turbo-compression cycle, a cooling system 100 using a turbo brayton cycle refrigeration system, and a main refrigeration system 200 using a hydrogen claude cycle refrigeration system is more specifically illustrated, and is different from embodiment 4 in that:
in this embodiment, the cooling system 100 is a turbine brayton cycle refrigeration system, the main refrigeration system 200 is a hydrogen craude cycle refrigeration system, and the low-temperature heat exchanger group 500 includes 6 low-temperature heat exchangers (first to sixth low-temperature heat exchangers) whose temperatures are from high to low.
The turbine brayton cycle refrigeration system used by the cooling system 100 includes a low-temperature turbine compressor I103, a water cooler 104, a low-temperature turbine expander 105, and a high-speed motor 106. The above-mentioned components are connected in the following order: the high-pressure outlet of the low-temperature turbine compressor I103, the water cooler 104, the hot end inlet of the pre-cooling heat exchanger 400, the cold end outlet of the pre-cooling heat exchanger 400, the inlet of the low-temperature turbine expander I105, the outlet of the low-temperature turbine expander I105, the cold end inlet of the pre-cooling heat exchanger 400, the hot end outlet of the pre-cooling heat exchanger 400 and the low-pressure inlet of the low-temperature turbine compressor I103 are sequentially connected to form a loop.
The low-temperature turbo compressor I103 and the low-temperature turbo expander I105 are mechanically coupled by a shaft on which a high-speed motor 106 is provided. In this embodiment, the operating principle of the turbine brayton cycle refrigeration system is as follows: a refrigeration working medium is compressed to high pressure by a low-temperature turbine compressor I103, the compression heat generated by compression is taken away by a water cooler 104 to be cooled to about room temperature, and the compressed and cooled working medium enters a precooling heat exchanger 400 to be precooled to about 100-120K by the returned refrigeration working medium; then, the working medium enters a low-temperature turboexpander I105 for expansion refrigeration, and the temperature of the working medium can be finally reduced to about 80-100K according to the difference between the working medium and the pressure after expansion; the low-temperature low-pressure working medium returns to the pre-cooling heat exchanger 400 to pre-cool the inflowing high-pressure working medium, the working medium of the main refrigeration cycle and the hydrogen of the liquefaction system 300, re-warms to about room temperature, leaves the pre-cooling heat exchanger 400, and finally returns to the low-pressure inlet of the low-temperature turbine compressor I103. The high-speed motor 106 provides main driving force to drive the low-temperature turbine compressor I103, and expansion work of the low-temperature turbine expander I105 is recovered through a shaft to provide auxiliary driving force for the low-temperature turbine compressor I103.
The hydrogen claude cycle refrigeration system employed by the main refrigeration system 200 includes a primary compressor 214 (working medium compressor), a primary water cooler 215, a secondary compressor 216 (working medium compressor), a secondary water cooler 217, an oil removal system 213, a low-temperature adsorption filter 221, a primary low-temperature turboexpander 232, a secondary low-temperature turboexpander 233, and a throttle valve 234. The connection relationship of the components is as follows: the primary compressor 214, the primary water cooler 215, the secondary compressor 216, the secondary water cooler 217, the oil removal system 213 and the inlet of the hot end of the precooling heat exchanger 400 are sequentially connected through a pipeline; after passing through the pre-cooling heat exchanger 400, the outlet of the cold end of the pre-cooling heat exchanger 400 is connected with the low-temperature adsorption filter 221, and then passes through the first-stage low-temperature heat exchanger 501;
the hydrogen pipeline is divided into two paths, wherein one path is firstly connected with a first-stage low-temperature turboexpander 232, then enters a second-stage low-temperature turboexpander 233 after passing through a third-stage low-temperature heat exchanger 505, is finally connected with a cold end inlet of a fourth-stage low-temperature heat exchanger 506, and returns to pass through the fourth-stage low-temperature heat exchanger 506, the third-stage low-temperature heat exchanger 505, the second-stage low-temperature heat exchanger 504, the first-stage low-temperature heat exchanger 501 and the precooling heat exchanger 400 in sequence, and finally converges into a pipeline between a first-stage water cooler 215 and a second-stage compressor 216;
the other path of the heat exchange liquid passes through a second-stage low-temperature heat exchanger 504, a third-stage low-temperature heat exchanger 505, a fourth-stage low-temperature heat exchanger 506 and a fifth-stage low-temperature heat exchanger 507 in sequence and is connected with a throttling valve 234; an outlet of the throttle valve 234 is connected with a cold-end inlet of a sixth-stage cryogenic heat exchanger 508 through a pipeline, and then returns to pass through the sixth-stage cryogenic heat exchanger 508, a fifth-stage cryogenic heat exchanger 507, a fourth-stage cryogenic heat exchanger 506, a third-stage cryogenic heat exchanger 505, a second-stage cryogenic heat exchanger 504, a first-stage cryogenic heat exchanger 501 and a precooling heat exchanger 400 in sequence, and finally is connected with a low-pressure inlet of the first-stage compressor 214.
The main refrigeration system 200 employing the hydrogen claude cycle refrigeration system operates on the following principle: the room-temperature low-pressure hydrogen working medium returned from the precooling heat exchanger 400 enters the first-stage compressor 214 to be compressed to medium pressure, is cooled to room temperature through the first-stage water cooler 215, then enters the second-stage compressor 216 to be further compressed to high pressure, is cooled to room temperature through the second-stage water cooler 217, and then enters the oil removal system 213 to remove most of oil gas impurities in the working medium; the high-pressure hydrogen after compression, cooling and oil removal firstly enters a precooling heat exchanger 400 to be precooled to about 77-100K.
Then removing residual particulate impurities solidified at low temperature through a low-temperature adsorption filter 221; hydrogen leaves the low-temperature adsorption filter 221 and enters a first-stage low-temperature heat exchanger 501 for precooling, then the hydrogen is divided into two paths, one path of hydrogen enters a first-stage low-temperature turbo expander 232 for expansion refrigeration, the temperature is reduced by 5-10K, the hydrogen enters a third-stage low-temperature heat exchanger 505 for further precooling, the hydrogen enters a second-stage low-temperature turbo expander 233 for expansion refrigeration, the temperature is reduced by 5-10K again, the pressure is reduced to medium pressure, then the hydrogen returns to pass through a fourth-stage low-temperature heat exchanger 506, the third-stage low-temperature heat exchanger 505, a second-stage low-temperature heat exchanger 504, a first-stage low-temperature heat exchanger 501 and a precooling heat exchanger 400 for cooling the inflow high-pressure hydrogen and the hydrogen of the liquefaction system 300, and finally the hydrogen flows into a hydrogen working medium flow between a first-stage water cooler 215 and a second-stage compressor 216;
the other path of hydrogen is further pre-cooled to about 20K through a second-stage low-temperature heat exchanger 504, a third-stage low-temperature heat exchanger 505, a fourth-stage low-temperature heat exchanger 506 and a fifth-stage low-temperature heat exchanger 507, isenthalpic throttling refrigeration is finally carried out through a throttle valve 234, the temperature of the hydrogen is continuously reduced to 18-20K and is partially liquefied, then the low-temperature low-pressure hydrogen sequentially returns to pass through a sixth-stage low-temperature heat exchanger 508, a fifth-stage low-temperature heat exchanger 507, a fourth-stage low-temperature heat exchanger 506, the third-stage low-temperature heat exchanger 505, the second-stage low-temperature heat exchanger 504, the first-stage low-temperature heat exchanger 501 and the pre-cooling heat exchanger 400 to cool the inflowing high-pressure hydrogen and the hydrogen of the liquefaction system 300, and finally returns to the low-pressure inlet of the first-stage compressor 214 to be compressed and circulated again.
In this embodiment, the components, connection mode and operation principle of the liquefaction system 300 are the same as those of embodiment 4.

Claims (10)

1. The hydrogen liquefaction system adopting low-temperature turbine compression circulation comprises a liquefaction system, a low-temperature heat exchanger group, a precooling system and a main refrigeration system for providing a cold source for the low-temperature heat exchanger group;
the liquefaction system comprises an orthoparahydrogen catalytic reactor I and n-stage orthoparahydrogen catalytic reactors sequentially connected in series with the orthoparahydrogen catalytic reactor I; the low-temperature heat exchanger group comprises n-grade low-temperature heat exchangers for respectively refrigerating and exchanging heat of n-grade ortho-para hydrogen catalytic reactors; the precooling system provides precooling cold energy for the para-hydrogen catalytic reactor I and the main refrigerating system respectively;
the device is characterized by also comprising a mixing ejector, a shaft-driven compressor and a throttling element;
the main refrigeration system comprises at least one turboexpander, and an output shaft of the turboexpander is in transmission connection with the shaft-driven compressor;
a return branch is led out from a pipeline at the discharge port of the n-1 stage of the orthohydrogen catalytic reactor, and working media in the return branch are sequentially throttled by a throttling element, subjected to heat exchange by at least one low-temperature heat exchanger, compressed by a shaft-driven compressor and precooled by a precooling system and then enter the mixing ejector as high-pressure fluid; or working medium of the return branch sequentially passes through throttling of the throttling element and heat exchange of at least one low-temperature heat exchanger to serve as low-pressure fluid to enter the mixer;
when the working medium is used as high-pressure fluid, the material at the outlet of the para-hydrogen catalytic reactor I is used as low-pressure fluid to enter the mixing ejector, and the mixed fluid sequentially enters the n-stage para-hydrogen catalytic reactor; when the working medium is used as a low-pressure fluid, the material at the outlet of the para-hydrogen catalytic reactor I is used as a high-pressure fluid and enters the mixing ejector, and the mixed material sequentially enters the n-stage para-hydrogen catalytic reactor after being compressed by the shaft-driven compressor and precooled by the precooling system.
2. The hydrogen liquefaction system of claim 1, wherein the throttling element is an expander, a throttle valve, or a bypass eductor.
3. The hydrogen liquefaction system of claim 2, further comprising a liquid hydrogen storage tank connected to the nth stage ortho-para hydrogen catalytic reactor by a conduit;
the throttling element is a bypass ejector, and the backflow branch is connected with a high-pressure inlet of the backflow branch; and a gas phase outlet of the liquid hydrogen storage tank is connected with a low-pressure inlet of the bypass ejector through a gas phase loop.
4. The hydrogen liquefaction system of claim 3, wherein the gas phase loop is connected with the low pressure inlet of the bypass ejector after heat exchange by the nth-stage low temperature heat exchanger.
5. The hydrogen liquefaction system of claim 4, wherein the working medium at the outlet of the bypass ejector exchanges heat with the n-1 st-stage low-temperature heat exchangers in sequence.
6. The hydrogen liquefaction system of claim 3, wherein the gas phase loop is directly connected to the low pressure inlet of the bypass eductor.
7. The hydrogen liquefaction system of claim 6, wherein the working medium at the outlet of the bypass ejector sequentially passes through nth-1 st-stage low-temperature heat exchangers for heat exchange.
8. The hydrogen liquefaction system of claim 1, wherein a compensation drive motor is provided on a shaft connecting the expander and the compressor.
9. The hydrogen liquefaction system of claim 1, wherein working media in the return branch exchange heat with the n-1 st cryogenic heat exchangers in sequence.
10. The hydrogen liquefaction system of claim 1, wherein the pre-cooling system comprises a pre-cooling heat exchanger and a cooling system providing a cooling source for the pre-cooling heat exchanger, and the pre-cooling heat exchanger provides cooling energy for the para-hydrogen catalytic reactor I and the main refrigeration system respectively.
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Cited By (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN115854651A (en) * 2022-11-25 2023-03-28 浙江大学 Hydrogen liquefaction method and device for precooling by using refrigerating machine

Citations (5)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
RU2309342C1 (en) * 2006-05-05 2007-10-27 Открытое акционерное общество криогенного машиностроения (ОАО "Криогенмаш") Hydrogen liquefying method with use of helium refrigeration cycle and apparatus for performing the same
CN106894918A (en) * 2017-03-13 2017-06-27 西北工业大学 A kind of mode pre-cooling cycle system suitable for assembly power cycle engine
CN108998068A (en) * 2018-08-22 2018-12-14 国家能源投资集团有限责任公司 DCL/Direct coal liquefaction system and coal direct liquefaction method
CN112361711A (en) * 2020-10-30 2021-02-12 北京航天试验技术研究所 Hydrogen liquefaction equipment provided with three turboexpander units connected in series
CN112361713A (en) * 2020-10-30 2021-02-12 北京航天试验技术研究所 Hydrogen liquefaction equipment provided with parallel turboexpander units

Patent Citations (5)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
RU2309342C1 (en) * 2006-05-05 2007-10-27 Открытое акционерное общество криогенного машиностроения (ОАО "Криогенмаш") Hydrogen liquefying method with use of helium refrigeration cycle and apparatus for performing the same
CN106894918A (en) * 2017-03-13 2017-06-27 西北工业大学 A kind of mode pre-cooling cycle system suitable for assembly power cycle engine
CN108998068A (en) * 2018-08-22 2018-12-14 国家能源投资集团有限责任公司 DCL/Direct coal liquefaction system and coal direct liquefaction method
CN112361711A (en) * 2020-10-30 2021-02-12 北京航天试验技术研究所 Hydrogen liquefaction equipment provided with three turboexpander units connected in series
CN112361713A (en) * 2020-10-30 2021-02-12 北京航天试验技术研究所 Hydrogen liquefaction equipment provided with parallel turboexpander units

Cited By (2)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN115854651A (en) * 2022-11-25 2023-03-28 浙江大学 Hydrogen liquefaction method and device for precooling by using refrigerating machine
CN115854651B (en) * 2022-11-25 2023-09-15 浙江大学 Hydrogen liquefaction method and device for precooling by utilizing refrigerator

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