WO2018119831A1 - Process and apparatus for establishing vacuum insulation under cryogenic condition - Google Patents
Process and apparatus for establishing vacuum insulation under cryogenic condition Download PDFInfo
- Publication number
- WO2018119831A1 WO2018119831A1 PCT/CN2016/112920 CN2016112920W WO2018119831A1 WO 2018119831 A1 WO2018119831 A1 WO 2018119831A1 CN 2016112920 W CN2016112920 W CN 2016112920W WO 2018119831 A1 WO2018119831 A1 WO 2018119831A1
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- WIPO (PCT)
- Prior art keywords
- insulation enclosure
- vacuum
- insulation
- enclosure
- filling gas
- Prior art date
Links
- 238000009413 insulation Methods 0.000 title claims abstract description 79
- 238000000034 method Methods 0.000 title claims abstract description 53
- 230000008569 process Effects 0.000 title claims abstract description 51
- 238000000926 separation method Methods 0.000 claims abstract description 5
- CURLTUGMZLYLDI-UHFFFAOYSA-N Carbon dioxide Chemical compound O=C=O CURLTUGMZLYLDI-UHFFFAOYSA-N 0.000 claims description 65
- 229910002092 carbon dioxide Inorganic materials 0.000 claims description 42
- 238000010926 purge Methods 0.000 claims description 42
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- 239000007790 solid phase Substances 0.000 claims description 9
- 239000012071 phase Substances 0.000 claims description 8
- 239000012774 insulation material Substances 0.000 claims description 6
- 239000010451 perlite Substances 0.000 claims description 6
- 235000019362 perlite Nutrition 0.000 claims description 6
- 238000001816 cooling Methods 0.000 claims description 5
- 239000004964 aerogel Substances 0.000 claims description 4
- 230000009466 transformation Effects 0.000 claims description 4
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- 229910052799 carbon Inorganic materials 0.000 description 1
- 239000010962 carbon steel Substances 0.000 description 1
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Images
Classifications
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- F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
- F17—STORING OR DISTRIBUTING GASES OR LIQUIDS
- F17C—VESSELS FOR CONTAINING OR STORING COMPRESSED, LIQUEFIED OR SOLIDIFIED GASES; FIXED-CAPACITY GAS-HOLDERS; FILLING VESSELS WITH, OR DISCHARGING FROM VESSELS, COMPRESSED, LIQUEFIED, OR SOLIDIFIED GASES
- F17C13/00—Details of vessels or of the filling or discharging of vessels
- F17C13/001—Thermal insulation specially adapted for cryogenic vessels
-
- 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
- F25J1/00—Processes or apparatus for liquefying or solidifying gases or gaseous mixtures
- F25J1/02—Processes or apparatus for liquefying or solidifying gases or gaseous mixtures requiring the use of refrigeration, e.g. of helium or hydrogen ; Details and kind of the refrigeration system used; Integration with other units or processes; Controlling aspects of the process
- F25J1/0243—Start-up or control of the process; Details of the apparatus used; Details of the refrigerant compression system used
- F25J1/0257—Construction and layout of liquefaction equipments, e.g. valves, machines
- F25J1/0261—Details of cold box insulation, housing and internal structure
-
- 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
- F25J3/00—Processes or apparatus for separating the constituents of gaseous or liquefied gaseous mixtures involving the use of liquefaction or solidification
- F25J3/02—Processes or apparatus for separating the constituents of gaseous or liquefied gaseous mixtures involving the use of liquefaction or solidification by rectification, i.e. by continuous interchange of heat and material between a vapour stream and a liquid stream
- F25J3/0295—Start-up or control of the process; Details of the apparatus used, e.g. sieve plates, packings
-
- 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
- F25J3/00—Processes or apparatus for separating the constituents of gaseous or liquefied gaseous mixtures involving the use of liquefaction or solidification
- F25J3/02—Processes or apparatus for separating the constituents of gaseous or liquefied gaseous mixtures involving the use of liquefaction or solidification by rectification, i.e. by continuous interchange of heat and material between a vapour stream and a liquid stream
- F25J3/04—Processes or apparatus for separating the constituents of gaseous or liquefied gaseous mixtures involving the use of liquefaction or solidification by rectification, i.e. by continuous interchange of heat and material between a vapour stream and a liquid stream for air
- F25J3/04763—Start-up or control of the process; Details of the apparatus used
- F25J3/04866—Construction and layout of air fractionation equipments, e.g. valves, machines
- F25J3/04945—Details of internal structure; insulation and housing of the cold box
-
- 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
- F25J3/00—Processes or apparatus for separating the constituents of gaseous or liquefied gaseous mixtures involving the use of liquefaction or solidification
- F25J3/06—Processes or apparatus for separating the constituents of gaseous or liquefied gaseous mixtures involving the use of liquefaction or solidification by partial condensation
- F25J3/0695—Start-up or control of the process; Details of the apparatus used
-
- F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
- F17—STORING OR DISTRIBUTING GASES OR LIQUIDS
- F17C—VESSELS FOR CONTAINING OR STORING COMPRESSED, LIQUEFIED OR SOLIDIFIED GASES; FIXED-CAPACITY GAS-HOLDERS; FILLING VESSELS WITH, OR DISCHARGING FROM VESSELS, COMPRESSED, LIQUEFIED, OR SOLIDIFIED GASES
- F17C2203/00—Vessel construction, in particular walls or details thereof
- F17C2203/03—Thermal insulations
- F17C2203/0391—Thermal insulations by vacuum
-
- F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
- F17—STORING OR DISTRIBUTING GASES OR LIQUIDS
- F17C—VESSELS FOR CONTAINING OR STORING COMPRESSED, LIQUEFIED OR SOLIDIFIED GASES; FIXED-CAPACITY GAS-HOLDERS; FILLING VESSELS WITH, OR DISCHARGING FROM VESSELS, COMPRESSED, LIQUEFIED, OR SOLIDIFIED GASES
- F17C2223/00—Handled fluid before transfer, i.e. state of fluid when stored in the vessel or before transfer from the vessel
- F17C2223/01—Handled fluid before transfer, i.e. state of fluid when stored in the vessel or before transfer from the vessel characterised by the phase
- F17C2223/0146—Two-phase
- F17C2223/0153—Liquefied gas, e.g. LPG, GPL
- F17C2223/0161—Liquefied gas, e.g. LPG, GPL cryogenic, e.g. LNG, GNL, PLNG
-
- 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
- F25J2290/00—Other details not covered by groups F25J2200/00 - F25J2280/00
- F25J2290/30—Details about heat insulation or cold insulation
-
- 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
- F25J2290/00—Other details not covered by groups F25J2200/00 - F25J2280/00
- F25J2290/42—Modularity, pre-fabrication of modules, assembling and erection, horizontal layout, i.e. plot plan, and vertical arrangement of parts of the cryogenic unit, e.g. of the cold box
Definitions
- the present invention relates to a process of establishing vacuum insulation for cryogenic equipment and an apparatus compatible with such process.
- Cryogenic processes such as cryogenic air separation and HYCO processes, often operate at temperatures below approximately-90°C. Such processes require insulation around the process equipment and interconnecting piping from surrounding en-vironment to prevent excessive heat leak into the process and water freezing around the equipment.
- Perlite and mineral wool have low heat conductivity and can be filled into a vessel housing the cryogenic equipment. Nitrogen purge is often required to remove moisture, oil or other flammable or corrosive components from the vessel.
- Vacuum insulation With vacuum insulation, the equipment is placed within a vessel and a vacuum is pulled on the annular space between the equipment and the vessel wall, which reduces heat transfer by conduction and convection. Vacuum insulation can provide more re-sistance to heat transfer and is preferred for processes operated below-150°C in compact vessels. However, an adequate vacuum is difficult and costly to produce at ambient temperature. Additional insulation materials, such as perlite, mineral wools, aerogel or polymeric foams used for creating and maintaining the vacuum insulation further increase cost.
- An object of the present invention is to avoid the time-consuming and costly process of creating a vacuum level harder than 5 absolute Pa at ambient temperature in in-sulation enclosure housing cryogenic equipment; a further object is to eliminate the use of insulation materials inside the insulation enclosure.
- a process for establishing an insulation enclosure comprises the following steps.
- a filling gas of a desired purity is provided; perform at least a first purging cycle to the insulation enclosure, which is characterized by evacuating the insulation enclosure from a first starting pressure to an intermediate vacuum, followed by re-pressuring the insulation enclosure with the filling gas back to a second starting pressure equal to or different from the first starting pressure; creating and maintaining a primary vacuum in the insulation enclosure filled mostly with the filling gas; operating the cryogenic equipment to cool the insulation enclosure and the filling gas to a temperature equal to or below that solidifies the filling gas, thus creating a final vacuum in the insulation enclosure; wherein starting from the primary vacuum, the filling gas undergoes transformation from gas phase to solid phase without going through liquid phase during the cooling caused by operation of the cryogenic equipment.
- the above process may further comprise a second and a third purging cycle with the filling gas following the first purging cycle, wherein in the second purging cycle, the insulation enclosure is evacuated from the second starting pressure until a second in-termediate vacuum and pressurized back to a third starting pressure, and in the third purging cycle, the insulation enclosure is evacuated from the third starting pressure until a third intermediate vacuum and pressurized back to a fourth starting pressure.
- first, second, third and fourth starting pressure of their respective purging cycles may be the same or different.
- first, second and third intermediate vacuum of their respective purging cycles may be the same or different.
- the starting pressure of any of the purging cycles may be at atmospheric pressure or above atmospheric pressure.
- the insulation enclosure may be pressurized with the filling gas to reach the first starting pressure.
- the filling gas may be carbon dioxide with a purity of equal to or better than 99.99%volume percentage.
- an insulation enclosure for a cryogenic equipment comprises a casing encompassing the cryogenic equipment, which is filled mostly with a filling gas of a desired purity.
- the insulation enclosure is evacuated to and maintained at a primary vacuum and a final vacuum is achieved in the insulation enclosure after the filling gas is solidified due to the operation of the cryogenic equipment, wherein starting from the primary vacuum, the filling gas undergoes transformation from gas phase to solid phase without going through liquid phase during the cooling of the insulation enclosure caused by the operation of the cryogenic equipment.
- a hard vacuum of lower than 1 absolute Pa can be achieved automatically, further reduces cost, time and labor.
- Figure 1 illustrates the vapor pressure of carbon dioxide at different temperature.
- Figure 2 presents the phase diagram of carbon dioxide.
- Figure 3 presents a schematic diagram of an insulation enclosure of the present invention.
- Cryogenic processes refer to processes carried out at low temperature, usually below -90°C, in some cases below-150°C.
- insulation around cryogenic equipment and inter-connecting pipes are necessary; and the lower the operation temperature, the more in-sulation is required.
- vacuum insulation a vacuum of below 5 absolute Pascal is required for cryogenic equipment operated around-170°C and a vacuum of below 1 absolute Pascal is required if the cryogenic equipment is operated around-190°C.
- Cryogenic equipment comprises rectification apparatus used in cryogenic air separation to produce oxygen, nitrogen, argon or other pure components of air.
- Cold boxes or cylindrical-shaped containers correspond to the insulation enclosure housing the cryogenic equipment.
- the casing of such insulation enclosure may be made of carbon steel to provide strong structural support and withstand the vacuum created within. Conventionally, to create a vacuum level of 1 Pa for a vacuum-tight space of 50m3, about 3 weeks of pumping time is needed with one turbo molecular pump.
- This invention discloses a method utilizing the physical property of certain gases to create adequate vacuum under cryogenic condition without extensive pumping.
- a gaseous component condenses into liquid or solid phase in a closed system
- the pressure attributed to such component within the closed system equals to the vapor pressure of the liquid or solid, which decreases non-linearly with the drop of rem- perature.
- Figure 1 presents a vapor pressure (mmHg) vs. temperature (°C) graph for carbon dioxide, and for a temperature of-170°C, the vapor pressure of pure carbon dioxide is 0.013 absolute Pascal.
- an insulation enclosure such as a cold box
- a pure filling gas such as CO 2
- the gas in contact with the cryogenic equipment becomes cold and condenses into solid phase due to the refrigeration produced during the cryogenic process.
- the gas Once the gas is solidified, its vapor pressure further decreases with the drop of temperature, thus hard vacuum can be established automatically within the cold box.
- the preferable filling gas is non-toxic, non-flammable, non-corrosive, relatively inexpensive and available. Additionally, the filling gas shall transform from gas phase to solid phase directly during the cryogenic process. This property of selected gas can be accessed using its phase diagram.
- a phase diagram is a graphical representation showing conditions (pressure, temperature, volume, etc. ) at which thermodynamically distinct phases occur and coexist at equilibrium.
- Figure 2 il-lustrates the phase diagram of carbon dioxide. Since the triple point of carbon dioxide is at 5.11 atm and-56.6°C, for pressure at or below atmospheric pressure, carbon dioxide transforms from gas phase to solid phase without passing through liquid phase when temperature drops. Thus, carbon dioxide is a good candidate as a filling gas for this invention.
- Other gases that condense from gas phase into solid phase directly at pressure equal or below atmospheric pressure include water, H 2 S, SO 2 , NH 3 , but they do not possess the other advantages as CO 2 does.
- carbon dioxide When carbon dioxide is selected as the filling gas, depending on the final vacuum required in the cold box, carbon dioxide of various degree of purity may be used. It is recommended to use a carbon dioxide gas with a purity of better than 99.99%volume percent for a final vacuum of lower than 1 absolute Pascal at-170°C.
- a purging cycle consists of the following steps: connect a pump and a carbon dioxide source to the insulation enclosure, for example, a cold box; at a starting pressure, shut off the carbon dioxide source and turn on the pump; remove the gaseous component inside the cold box until its pressure drops to a pre-determined intermediate vacuum; turn off the pump and fill the cold box with carbon dioxide until the pressure reaches a pre-determined starting pressure for the next purging cycle or pumping step. More than one purging cycle, preferably three purging cycles may be performed to effectively replace air originally inside the cold box with the filling gas.
- the starting pressure of the first purging cycle may be atmospheric pressure or a pressure above.
- the in-sulation enclosure can be pressurized with air or the filling gas carbon dioxide.
- Re-spective starting pressure of the following purging cycles can be the same as the first starting pressure, or different.
- the intermediate vacuum of each purging cycle can be the same.
- the cold box is then filled mostly with carbon dioxide of a selected purity and is at a fourth starting pressure.
- a final pumping step is carried out to remove carbon dioxide until the pressure inside the cold box reaches a pre-determined primary vacuum followed by sealing the cold box.
- the primary vacuum may be harder, softer or equal to the intermediate vacuum. All the purging and pumping steps can be performed in shop and the sealed cold box is then ready to be transported to different sites. Once on site, final vacuum will be established when cryogenic process starts and the temperature inside the cold box decreases.
- the value of primary vacuum is determined taking into account the following factors.
- to maintain final vacuum at cryogenic temperature consumes refrigeration energy from the cryogenic process; thus with a low primary vacuum, less refrigeration energy is needed and the efficiency of the cryogenic equipment is improved.
- to create a very low primary vacuum demands the use of expensive pumps such as turbo molecular pumps and requires a substantial amount of pumping time. To balance time, cost and energy-saving, it is recommended to select a primary vacuum level that approaches the best vacuum level readily attainable using a mechanical pump, for instance, around 100 Pa.
- Insulation materials such as perlite, mineral wool and gel, including aerogel, can be filled into the insulation enclosure before purging with the filling gas to further reduce heat leak into the cryogenic process. Since vacuum insulation created through the present invention is very efficient, it is not necessary to employ the above insulation materials for maintaining a vacuum under 1 absolute Pa at or below-150°C.
- Thermal radiation shields typically take the form of radiation shielding sheets or radiation shielding coating.
- Radiation shielding sheets are commonly thin layers made of good thermal conductors including copper and aluminum. They can be arranged as single layer or spaced-multi layers surrounding, but not directly touching the low tem-perature component. For instance, the radiation shielding sheet shall completely surround the cryogenic equipment without gaps or holes, or they can contact and cover the entire inner surface of the casing encompassing the cryogenic equipment.
- Radiation shielding coating usually consists of materials with high emissivity.
- the emissivity of an object is defined as the ratio of radiant energy emitted by that object divided by the radiant energy which a blackbody would emit at the same temperature.
- coating with a high emissivity on high temperature component causes more radiation from the high temperature component to be absorbed, and less radiation is reflected onto the low temperature component.
- radiation shielding coating may be disposed on the inner surface of the casing.
- Choices of suitable coating may comprise emissive substances, which also have low outgassing properties, such as paint, amythrocite, polytetrafluoroethylene, oxide or glass adapted to absorb radiation.
- cryogenic equipment 4 is surrounded by a radiation shielding sheet 3, both are housed in the insulation enclosure 1.
- Inlet 5 may be used to fill the insulation enclosure 1 with CO 2
- vacuum pump may be connected to the insulation enclosure 1 through port 6 to create vacuum insulation 2. All calculations are based on a hypo-thetical process and are conducted using well-established mathematic and ther-modynamic equations.
- each respective starting pressure is set at 110000 absolute Pa and each respective intermediate vacuum is set at 1000 absolute Pa.
- the V%of CO 2 and remaining impurity in the cold box are calculated, and again listed in the column of Table 1 labeled as “after 2 nd PC” and “after 3 rd PC” respectively.
- the cold box is then evacuated to reach the pre-determined primary vacuum of 100 absolute Pa.
- the cold box is then sealed to form a vacuum-tight enclosure.
- the final vacuum in the cold box is calculated and listed in the column of Table 1 labeled as “Final vacuum (Pa) ” assuming the temperature within the cold box is decreased to-170°C.
- Table 1 illustrates that for a final pressure lower than 1 absolute Pa at around-170°C, the purity of CO 2 needs to be higher than 99.99 V%, and the higher the purity, the lower the final pressure obtained within the cold box.
- Table 2 illustrates that to achieve adequate final vacuum, it is not necessary to choose a very hard intermediate vacuum during each purging cycle. In fact, an intermediate vacuum around 1000 Pa is sufficient.
- Table 3 illustrates that the final pressure in the cold box at around-170°C drops along with the decrease of primary vacuum in the cold box at ambient temperature. Nevertheless, a primary vacuum of 100 Pa is sufficient.
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- Engineering & Computer Science (AREA)
- Mechanical Engineering (AREA)
- General Engineering & Computer Science (AREA)
- Physics & Mathematics (AREA)
- Thermal Sciences (AREA)
- Filling Or Discharging Of Gas Storage Vessels (AREA)
- Thermal Insulation (AREA)
- Separation By Low-Temperature Treatments (AREA)
Abstract
Description
Claims (34)
- A process for establishing an insulation enclosure, comprising:a) providing an insulation enclosure having a casing encompassing a cryogenic equipment;b) providing a filling gas of a desired purity;c) performing a first purging cycle to the insulation enclosure, char-acterized by evacuating the insulation enclosure from a first starting pressure to a first intermediate vacuum, followed by re-pressuring the insulation enclosure with the filling gas to a second starting pressure;d) creating and maintaining a primary vacuum in the insulation enclosure filled mostly with the filling gas;e) operating the cryogenic equipment to cool the insulation enclosure and the filling gas to a temperature equal to or below the temperature that solidifies the filling gas, thus creating a final vacuum in the in-sulation enclosure; andwherein starting from the primary vacuum, the filling gas undergoes transformation from gas phase to solid phase directly during cooling caused by the operation of the cryogenic equipment.
- The process of claim 1, wherein the insulation enclosure is a cold box or a cylindrical enclosure.
- The process of claim 1, wherein the filling gas is carbon dioxide.
- The process of claim 3, wherein the purity of carbon dioxide is equal to or better than 99.99%volume percentage.
- The process of claim 1, wherein the cryogenic equipment comprises rectification apparatus used in cryogenic separation or storage apparatus for cryogenic products.
- The process of claim 1, characterized in that the first purging cycle is followed by a second purging cycle and a third purging cycle with the filling gas, wherein each purging cycle is characterized by its re-spective second and third starting pressure and second and third in-termediate vacuum.
- The process of claim 6, wherein the insulation enclosure is pressurized with the filling gas to a forth starting pressure after the third purging cycle and the primary vacuum is created by evacuating the in-sulation enclosure therefrom.
- The process of claim 6, wherein the starting pressure of one of the purging cycles is about atmospheric pressure.
- The process of claim 6, wherein the starting pressure of one of the purging cycles is above atmospheric pressure.
- The process of claim 1, wherein before the first purging cycle, the insulation enclosure is pressurized with the filling gas to the first starting pressure.
- The process of claim 6, wherein the starting pressure and the in-termediate vacuum of each purging cycle are the same.
- The process of claim 11, wherein the intermediate vacuum of each purging cycle is about 1000 absolute Pascal.
- The process of claim 11, wherein the primary vacuum is about 100 absolute Pascal.
- The process of claim 1, wherein the cryogenic equipment is operated at a temperature below -150℃.
- The process of claim 1, wherein the final vacuum in the insulation enclosure is below 1 absolute Pascal.
- The process of claim 1, wherein the insulation enclosure does not contain any insulation materials including perlite or aerogel.
- The process of claim 1, wherein a thermal radiation shield is disposed inside the insulation enclosure.
- The process of claim 17, wherein the thermal radiation shield comprises radiation shielding sheets and radiation shielding coating.
- The process of claim 18, wherein the radiation shielding sheets are made of copper or aluminum.
- The process of claim 19, wherein the radiation shielding sheet is covering the inner surface of the casing encompassing the cryogenic equipment.
- The process of claim 17, wherein the radiation shielding coating is disposed on the inner surface of the casing.
- An insulation enclosure for a cryogenic equipment, comprising:a) a casing encompassing the cryogenic equipment and the insulation enclosure being filled mostly with a filling gas of a desired purity;b) said insulation enclosure being evacuated to and maintained at a primary vacuum;c) a final vacuum being achieved in the insulation enclosure after the filling gas is solidified during the cooling caused by the operation of the cryogenic equipment; andwherein starting from the primary vacuum, the filling gas undergoes transformation from gas phase to solid phase directly during the cooling of the insulation enclosure caused by the operation of the cryogenic equipment.
- The insulation enclosure of claim 22, characterized by that it does not contain any insulation materials including perlite or aerogel.
- The insulation enclosure of claim 22, wherein the filling gas comprises carbon dioxide.
- The insulation enclosure of claim 24, wherein the purity of carbon dioxide is equal to or better than 99.99%volume percentage.
- The insulation enclosure of claim 22, wherein the cryogenic equipment comprises rectification apparatus used in cryogenic separation or storage apparatus for cryogenic products.
- The insulation enclosure of claim 26, wherein the cryogenic equipment is operated at a temperature below -150℃.
- The insulation enclosure of claim 22, wherein the primary vacuum is about 100 absolute Pascal.
- The insulation enclosure of claim 22, wherein the casing has connection ports for evacuating and pressurizing the insulation enclosure.
- The insulation enclosure of claim 22, wherein a thermal radiation shield is disposed inside the insulation enclosure.
- The insulation enclosure of claim 30, wherein the thermal radiation shield comprises radiation shielding sheets and radiation shielding coating.
- The insulation enclosure of claim 31, wherein the radiation shielding sheets are made of copper or aluminum.
- The insulation enclosure of claim 31, wherein the radiation shielding coating is covering the inner surface of the casing en-compassing the cryogenic equipment.
- The insulation enclosure of claim 30, wherein the radiation shielding coating is disposed on the inner surface of the casing.
Priority Applications (6)
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BR112019011062-3A BR112019011062B1 (en) | 2016-12-29 | 2016-12-29 | INSULATION ENCLOSURE FOR A CRYOGENIC EQUIPMENT AND PROCESS FOR ESTABLISHING AN INSULATION ENCLOSURE |
PCT/CN2016/112920 WO2018119831A1 (en) | 2016-12-29 | 2016-12-29 | Process and apparatus for establishing vacuum insulation under cryogenic condition |
US16/474,102 US20200248872A1 (en) | 2016-12-29 | 2016-12-29 | Process and apparatus for establishing vacuum insulation under cryogenic condition |
EP16925226.9A EP3563080A4 (en) | 2016-12-29 | 2016-12-29 | Process and apparatus for establishing vacuum insulation under cryogenic condition |
JP2019530721A JP6865282B2 (en) | 2016-12-29 | 2016-12-29 | Processes and equipment for establishing vacuum insulation under cryogenic conditions |
CN201680091542.1A CN110073135B (en) | 2016-12-29 | 2016-12-29 | Method and device for establishing vacuum insulation under low temperature condition |
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PCT/CN2016/112920 WO2018119831A1 (en) | 2016-12-29 | 2016-12-29 | Process and apparatus for establishing vacuum insulation under cryogenic condition |
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WO2018119831A1 true WO2018119831A1 (en) | 2018-07-05 |
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US (1) | US20200248872A1 (en) |
EP (1) | EP3563080A4 (en) |
JP (1) | JP6865282B2 (en) |
CN (1) | CN110073135B (en) |
BR (1) | BR112019011062B1 (en) |
WO (1) | WO2018119831A1 (en) |
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CN112413392A (en) * | 2020-11-18 | 2021-02-26 | 成都德信达能源科技中心(有限合伙) | Liquid hydrogen cold insulation storage device and storage method |
CN114893951B (en) * | 2022-05-10 | 2023-10-27 | 重庆炘扬航能源有限公司 | Liquefied natural gas cold box precooling equipment |
FR3135133B3 (en) | 2022-06-13 | 2024-03-29 | Air Liquide | Distillation apparatus required to operate at temperatures below 0°C |
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Also Published As
Publication number | Publication date |
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EP3563080A1 (en) | 2019-11-06 |
EP3563080A4 (en) | 2020-08-05 |
JP6865282B2 (en) | 2021-04-28 |
BR112019011062B1 (en) | 2021-12-28 |
US20200248872A1 (en) | 2020-08-06 |
CN110073135A (en) | 2019-07-30 |
CN110073135B (en) | 2021-08-03 |
JP2020509298A (en) | 2020-03-26 |
BR112019011062A2 (en) | 2019-10-01 |
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