CN113154713A

CN113154713A - Low-temperature refrigeration method and system

Info

Publication number: CN113154713A
Application number: CN202110172118.2A
Authority: CN
Inventors: 袁一军
Original assignee: Hunan Yali Technology Development Co Ltd
Current assignee: Hunan Yali Technology Development Co Ltd
Priority date: 2021-02-08
Filing date: 2021-02-08
Publication date: 2021-07-23
Anticipated expiration: 2041-02-08
Also published as: CN113154713B

Abstract

The invention provides a low-temperature refrigeration method and a system thereof, wherein the method utilizes a refrigerant compression type refrigeration system or other cold sources to cool compressed gas as the inlet air of a scroll, the low-temperature exhaust at the cold end of the scroll is used for the refrigeration purpose, and the scroll and the refrigerant compression type refrigeration system or other cold sources can run simultaneously or successively. The efficiency of the air compressor is related to the refrigerating efficiency of the scroll, the energy consumption of the air compressor is high, particularly the efficiency of the miniature air compressor is lower, so that the refrigerating efficiency of the scroll is low. The invention has the characteristics of high efficiency, high reliability, less energy consumption, low cost and the like, and the application of the invention is that the low-temperature refrigeration system originally limited to special occasions enters into the common wide fields, including various fields of industry, agriculture, commerce, civilian use and the like.

Description

Low-temperature refrigeration method and system

Technical Field

The present invention relates to a low temperature refrigeration method and system, and more particularly, to a low temperature refrigeration method and system and a low temperature storage system using a refrigerant compression refrigeration system and a scroll.

Background

The low-temperature refrigeration system at present mainly adopts compression refrigeration, and the scroll refrigeration is mainly used for the process refrigeration of a cold gun. The refrigeration system used in the common low-temperature compression type refrigeration system, such as a refrigerator and a cold storage, generally provides the temperature of more than minus 45 ℃, and in many occasions, including the fields of biological medicine, scientific experiments, military affairs and the like, a refrigeration system with lower temperature is needed, and if vaccines are stored at the temperature of minus 70 ℃ or even lower. Meanwhile, in the industrial civil and commercial fields, the coffee has a plurality of new applications, such as https:// comeneer. com/, a pioneer company in the United states, coffee is newly invented, the coffee is processed at the temperature of-321 ℃ F., and is stored and transported at the ultralow temperature, so that the refrigeration and storage system at the ultralow temperature is required. Along with the upgrading of mechanical manufacturing, higher requirements are put forward on the assembly precision of a plurality of metal parts and the stability, precision and wear resistance of metal materials, and the low-temperature treatment is particularly important. Through low-temperature treatment, the retained austenite in the heat treatment process can be reduced, the size is stabilized, the wear resistance and hardness of the product can be improved, and the residual stress of the material is released; the assembly precision of the parts can be improved by low-temperature processing, and the temperature range required by various mechanical cold processing equipment, such as Shenzhen Shenjieli science and technology company, is increased to-40 ℃ to-196 ℃.

The low-temperature refrigeration system is most widely applied to refrigerators, the temperature of a common low-temperature refrigerator is generally-20 ℃ to-40 ℃, the temperature of an ultra-low-temperature refrigerator is-40 ℃ to-100 ℃, the temperature of a deep-cooling refrigerator is lower than-100 ℃, the temperature higher than-153 ℃ belongs to the range of normal cooling, and the temperature lower than-153 ℃ belongs to the range of low temperature, and the refrigerators belong to the range of normal cooling. Therefore, most of the low-temperature refrigerators at present adopt refrigerant compression refrigeration, and cascade compression is adopted at ultralow temperature and deep low temperature, but a small part of the refrigerators adopt low-temperature refrigeration technology, such as stirling refrigeration, to realize the refrigerator with the ordinary refrigeration temperature range, such as www.stirlingultracold.com.

The adoption of the cascade compression refrigeration mainly has the following problems:

1) the system is complex, the failure rate is high, and the reliability is poor;

2) special low-temperature compressors and refrigerants are needed, the production and manufacturing difficulty is high, the maintenance and the repair are difficult, and special training professionals are needed;

3) the temperature passive range is large, the temperature control precision is low, and the temperature fluctuation range can reach more than 5 ℃;

4) the refrigeration efficiency is low, taking a refrigerator at minus 70 ℃ as an example, the COP is only 5%, and the refrigeration efficiency is sharply reduced along with the reduction of the temperature;

5) the starting and recovery time is long, namely the time for reducing the temperature from the normal temperature state to the low temperature is long, and the time for recovering the temperature after the door is opened is long.

6) The refrigerator is easy to frost, and needs to be cleaned regularly, so that the refrigerator is opened frequently.

7) Large volume and heavy weight.

8) The production cost is high, the price is expensive, and the price ranges from tens of thousands yuan to hundreds of thousands yuan of RMB.

The adoption of stirling refrigeration mainly has the following problems:

1) the Stirling belongs to low-temperature refrigeration equipment, and the technical threshold of the Stirling is high;

2) special Stirling refrigerant and gas refrigerant are needed, the production and manufacturing difficulty is high, the maintenance and the repair are difficult, and special training professionals are needed;

3) helium is used as a refrigerant, and is a rare gas, so that the resource is limited, the helium is difficult to obtain in a large amount, and the requirement of wide use cannot be met.

4) The refrigeration efficiency is called as cascade type, but is still very low, taking a refrigerator at minus 70 ℃ as an example, the COP of the refrigeration is about 7-10%, and the refrigeration efficiency is sharply reduced along with the reduction of the temperature;

5) the starting and recovery time is long, namely the time for reducing the temperature from the normal temperature state to the low temperature is long, and the time for recovering the temperature after the door is opened is long. Taking a refrigerator product at-70 ℃ of Stirling ultracold company as an example, the starting time is 6.5 hours, and the recovery time for opening the door is 35 minutes.

7) Large volume and heavy weight.

Disclosure of Invention

The invention provides a low-temperature refrigeration method aiming at the defects of the prior art, which utilizes a refrigerant compression type refrigeration system or other cold sources to cool compressed gas as the inlet air of a scroll, the low-temperature exhaust at the cold end of the scroll is used for the refrigeration purpose, and the scroll and the refrigerant compression type refrigeration system or other cold sources can run simultaneously or successively.

Furthermore, a refrigerant compression type refrigerating system or other cold sources are also used for cooling the scroll pipe at the same time, so that the efficiency and the refrigerating capacity of the scroll pipe are improved; or after the low-temperature exhaust at the cold end of the scroll pipe completes the refrigeration purpose, part or all of the low-temperature exhaust returns to the inlet of the gas compressor and enters the gas compressor; or the exhaust gas at the hot end is partially or completely reused, namely, the exhaust gas at the hot end is partially or completely returned to the inlet of the gas compressor to enter the gas compressor, the exhaust gas of the gas compressor is cooled by a refrigerant compression type refrigerating system or other cold sources and then is used as the inlet gas of the scroll, and the cooling is carried out by utilizing the cold energy provided by the refrigerant compression type refrigerating system or utilizing other cold sources.

Further, the method comprises the following two ways or a combination of the two ways to make the cold end of the scroll obtain exhaust with lower temperature:

the first method is as follows: after the cold end of the scroll is exhausted to finish the refrigeration purpose, returning a part of compressed gas for further cooling the compressed gas cooled by a refrigerant compression type refrigeration system or other cold sources;

the second method comprises the following steps: two or more stages of cascade refrigeration using two or more refrigeration combinations as claimed in claim 1, wherein the last stage is used for refrigeration purposes and the last stage provides refrigeration to the scroll of the next stage to further cool the compressed gas which is cooled by the refrigerant compression refrigeration system or other source of cooling, so that the temperature of the gas entering the scroll of the lowest stage is further reduced to obtain a lower temperature exhaust at the cold end of the scroll.

The current heat preservation method completely ignores the limitation of the second law of thermodynamics on energy utilization, namely that energy is of a quality and is devalued in the exchange process. Taking the heat preservation of a refrigerator as an example, the adopted method is to utilize cold energy at the temperature below zero, such as cold energy at the temperature of minus 70 ℃ to resist the heat energy of the environment, such as heat energy at the temperature of 20 ℃, so that the thermodynamic perfection of the method is 0 from the viewpoint of the thermodynamic perfection, and an ideal method or a method with the thermodynamic perfection of 100 percent is to utilize the cold energy at the temperature of minus 70 ℃ to 20 ℃ to absorb the heat energy of the environment, namely heat absorption fluid at the temperature of minus 70 ℃ to 20 ℃ is continuously arranged in the enclosure from the heat preservation environment to the outdoor environment to absorb the heat transferred from the outdoor environment to the heat preservation environment. Of course, the actual approach is to arrange one or more fluids within the enclosure that absorb heat between ambient and warm ambient temperatures, although less effective than a continuous temperature arrangement. The method can greatly reduce the quality of energy required by heat preservation of the refrigerator, thereby improving the efficiency of the refrigerating system. On the other hand, the law of depreciation of energy, which is a bad place in designing an energy system and is hoped to be reduced as much as possible, is beneficial to heat preservation because when a heat absorbing fluid is arranged in the enclosure, due to the law of depreciation of energy, the temperature difference exists between the fluid and a heat preservation material, so that the whole heat transfer temperature difference from the outdoor environment to the heat preservation environment is reduced, and the cold quantity required by heat preservation is reduced, therefore, the new heat preservation method not only can reduce the quality of the refrigerating capacity required by heat preservation, but also can reduce the required refrigerating capacity.

The invention also provides a low-temperature refrigerating system, which comprises a gas compressor, a scroll and a compressed gas cooling device, wherein the outlet of the gas compressor is connected with the inlet of the compressed gas cooling device through a gas pipeline; the compressed gas cooling device is a secondary refrigerant heat exchanger and a refrigerant compression refrigerating system.

Furthermore, the system also comprises a scroll cooler for cooling the outer wall of the scroll and/or the gas in the scroll, the scroll cooler is cooled by the refrigerant or the secondary refrigerant of the refrigerant compression refrigeration system, and the scroll cooler is positioned in the scroll and/or outside the scroll or integrated with the compressed gas cooling device. Or the inlet of the gas compressor is connected with one or more of the environment, the exhaust port of the device refrigerated by the low-temperature refrigeration system and the exhaust port at the hot end of the scroll. The gas compressor exhaust port is provided with a radiator, or the low-temperature refrigeration system is also matched with a gas storage tank, and the gas storage tank is connected with a hot fluid inlet of the compressed gas cooling device.

The invention also provides an energy storage low-temperature refrigeration system, which comprises an air storage tank, a scroll pipe and a compressed air cooling device, wherein an outlet of the air storage tank is connected with an inlet of the compressed air cooling device; the compressed air cooling device is a secondary refrigerant heat exchanger or a refrigerant compression refrigeration system.

Furthermore, the system also comprises a scroll cooler for cooling the outer wall of the scroll and/or the gas in the scroll, the scroll cooler is cooled by the refrigerant or the secondary refrigerant of the refrigerant compression refrigeration system, and the scroll cooler is positioned in the scroll and/or outside the scroll or integrated with the compressed gas cooling device. Or the system is also matched with an air compressor which is connected with the inlet of the compressed air cooling device.

The invention also provides a scroll with a cooler, wherein the cooler comprises one or more coolers for cooling the outer wall of the scroll, the gas in the scroll and the gas inlet of the scroll, the coolers for cooling the outer wall of the scroll and the gas inlet of the scroll are arranged outside the scroll, the coolers for cooling the gas in the scroll are arranged inside the scroll, and the coolers adopt the refrigerant or the secondary refrigerant of a refrigerant compression refrigeration system for refrigeration.

The scroll refrigeration is a simple and reliable method for refrigerating by using compressed air, but the main problems are that the refrigeration efficiency is low, the temperature drop of single-stage refrigeration is limited, low enough low temperature cannot be obtained, the required air pressure is high, the refrigerating capacity is small, meanwhile, the proportion of the available effective refrigerating capacity to the total refrigerating capacity is low, for example, a cold gun is taken as an example, the air inlet temperature is 30 ℃, the temperature is reduced to-20 ℃, the total refrigeration refers to the refrigeration from 30 ℃ to-20 ℃, the temperature difference is 50 ℃, and the refrigeration really available by the cold gun is only about 10 ℃, namely-10 ℃ to-20 ℃. Improve the scroll refrigeration, mainly through reducing scroll entry air temperature, make the scroll obtain sufficient low temperature, increase the air density who gets into the scroll simultaneously, increase the mass flow, increase the refrigerating output, reduce the temperature of scroll hot junction through forced cooling, improve the cold and hot air separation efficiency of scroll, increase the temperature drop of cold junction, reduce the pressure of scroll entry air, when reducing compressed air's energy consumption, reduce the hot junction load, and forced cooling cools down and reduces scroll entry air pressure and combines, can obtain reasonable temperature drop and cold gas proportion, obtain higher refrigeration efficiency. By combining with the heat preservation method, the proportion of the available effective refrigerating capacity of the scroll to the total refrigerating capacity can be fully improved.

The present invention also provides a cryogenic storage system comprising a storage compartment and a cryogenic refrigeration system according to claim 4 or an energy storing cryogenic refrigeration system according to claim 6 for refrigerating the storage compartment, including refrigeration of refrigerators, freezers and the like.

The invention also provides another low-temperature storage system which comprises a gas compressor, a refrigerant compression system, a scroll, a low-temperature storage chamber, a high-temperature storage chamber and a fan, wherein the refrigerant compression system comprises a throttling device, a condenser, a refrigerant compressor, a first evaporator and a third evaporator. The low-temperature storage chamber is arranged in the high-temperature storage chamber, and the high-temperature storage chamber is used for storing articles or used as an enclosure of the low-temperature storage chamber. The outer wall of the low-temperature storage chamber is further provided with a heat insulation structure, a porous heat insulation core body is filled in the heat insulation structure, a first gas channel and a second gas channel are arranged on two sides of the heat insulation core body, the first gas channel is in contact with the outer wall of the low-temperature storage chamber, and the second gas channel is located on the outermost side of the low-temperature storage chamber. The first evaporator is arranged on the outer wall of the scroll, the outlet of the throttling device is connected with the refrigerant inlet of the first evaporator, the refrigerant outlet of the first evaporator is connected with the refrigerant inlet of the third evaporator, the refrigerant outlet of the third evaporator is connected with the inlet of the compressor, the outlet of the compressor is connected with the inlet of the condenser, and the outlet of the condenser is sequentially connected with the inlet of the throttling device to form a refrigerant compression system. The outlet of the gas compressor is connected with the compressed air inlet of the first evaporator, the compressed air outlet of the first evaporator is connected with the air inlet of the scroll, the cold end outlet of the scroll is connected with the inlet of the first gas passage of the low-temperature storage chamber, and the outlet of the second gas passage and the outlet of the hot end of the scroll are simultaneously connected with the inlet of the gas compressor; the air inlet and outlet of the high-temperature storage chamber, the air inlet and outlet of the third evaporator and the fan are sequentially connected to form circulation, so that the refrigerant of the high-temperature storage chamber is cooled by the third evaporator, or the second evaporator is arranged in the scroll and is connected with the first evaporator in series or in parallel.

The efficiency of the air compressor is related to the refrigerating efficiency of the scroll, the energy consumption of the air compressor is high, particularly the efficiency of the miniature air compressor is lower, so that the refrigerating efficiency of the scroll is low.

The improvement of the scroll and the air compressor can be realized by combining with general high-efficiency refrigerant compression refrigeration, as is well known, the efficiency of the prior general compression refrigeration for air conditioning and refrigeration is 1 to 2 orders of magnitude higher than that of a low-temperature refrigeration mode, such as Stirling, and special low-temperature cascade compression refrigeration, and the full utilization of the general high-efficiency refrigerant compression refrigeration is one of the characteristics of the invention.

The energy storage of the refrigerating system, especially for cold chain transportation system, and the utilization of renewable energy, and the field environment, etc., the invention can utilize the compressed air to realize the energy storage at the same time.

The reliability of the low-temperature refrigeration system is much lower than that of the conventional refrigeration system, the low-temperature refrigeration system is often used for special purposes such as biological vaccines and the like, and the reliability requirement is high.

The low-temperature refrigeration system is very expensive, taking a refrigerator as an example, the refrigerator with the same volume is dozens of times or even hundreds of times of the common refrigerator, and compared with the common refrigeration system, the system of the invention has the same order of magnitude of price, which is greatly lower than the cost of the current low-temperature refrigerator.

The invention has the characteristics of high efficiency, high reliability, less energy consumption, low cost and the like, the application of the invention can enable a low-temperature refrigeration system originally limited to special occasions to enter the common wide fields, including various fields of industry, agriculture, business, civilian use and the like, conditions are provided, such as a household and commercial refrigerator, the domestic temperature is-18 ℃, the domestic temperature is-40 ℃ in practice, and researches show https:// www.fightbac.org/food-safety-consumption/40-or-below/? The gcrid ═ EAIQbCmI 3PCyzvCD7gIVVBh9Ch2ZPGOLEAAYBCAAEgLBrPD _ BwE, which is lower than minus 40, can reduce diseases caused by bacteria generated by frozen food, especially for pregnant women and old people, while the low-temperature quick freezing is also beneficial to reducing the passing time of the maximum ice crystal generating zone, better preserving delicate flavor and nutrition, for example, tuna requires the freezing temperature to be minus 60 ℃.

Drawings

Figure 1 is a basic principle diagram of the invention,

FIG. 2 is a schematic diagram of a system for refrigerating a low temperature storage compartment

FIG. 3 is a schematic diagram of the air intake refrigeration of the air compressor

FIG. 4 shows the situation where the exhaust gas is directly exhausted from the hot end of the scroll

FIG. 5 shows the storage compartment with a heat exchanger

FIG. 6 shows the inside of the enclosure of the storage room containing an exhaust heat exchanger

FIG. 7 is a schematic diagram of the refrigeration by the compressed air in the air storage tank

FIG. 8 shows a case with two refrigerant refrigeration cycles

FIG. 9 shows the interior of the enclosure containing the exhaust heat exchanger and the refrigerant heat exchanger

FIG. 10 is a schematic view showing the heat preservation of a conventional storage room

FIG. 11 is a schematic view of the heat preservation of the storage compartment according to the present invention

FIG. 12 is a schematic view of cooling the scroll

FIG. 13 shows a case with a blower

FIG. 14 contains multiple air compressors

FIG. 15 shows the case of self-cooling of the scroll

FIG. 16 is a schematic diagram of scroll cascade refrigeration

FIG. 17 shows scroll cascade refrigeration with self-cooling of the scroll

FIG. 18 shows a configuration in which two storage compartments are provided, one inside the other

FIG. 19 shows a case of a double storage chamber in which a scroll cooler and a compressed air cooler are integrated

FIG. 20 shows a dual storage chamber case in which a scroll cooler and a compressed air cooler are integrated

Detailed Description

As shown in fig. 1, a refrigeration system 100 including a scroll and a refrigerant compression refrigeration system includes a gas compressor 101, a compressed gas radiator 1011, a refrigerant compression system 102, a scroll 103, a gas pipeline 104, and the refrigerant compression system 102 is a general system including a condenser 1021, a refrigerant compressor 1022, an evaporator 1023 and a throttle 1024. The inlet air is compressed by the gas compressor 101, cooled by 1023 and then enters 103 the vortex tube, the cold end of the vortex tube gets the cold gas for refrigeration purpose, the hot end is hot exhaust.

The refrigerant compression system can also be replaced by other cold sources, including cold sources of a centralized air conditioning system and a cooling system, or cold sources of a technological process, such as a recycling cold source in the natural gas industry, and the evaporator is changed into a secondary refrigerant heat exchanger.

Because the scroll inlet air is cooled, the cold end of the scroll can obtain lower-temperature gas for low-temperature refrigeration.

In order to obtain better cooling effect for the scroll, the scroll may be cooled, as shown in fig. 12 and the like.

Fig. 2 illustrates that the cycle of fig. 1 can be used for cooling and cold keeping of a low-temperature storage room, including a refrigerator, a freezer and the like, to achieve a temperature lower than that of a conventional refrigerator and freezer, and the temperature of the conventional storage room is generally higher than-40 ℃, and the method of the present invention can provide a temperature far lower than-40 ℃.

The system 200 comprises a gas compressor 201, a compressed gas radiator 2011, a refrigerant compression system 202, a scroll 203, a gas pipeline 204 and a storage chamber 205, wherein the refrigerant compression system 202 is a universal system, air is compressed through the gas compressor 201, is cooled through the refrigerant compression system 202, then enters the scroll 203, cold gas is obtained at the cold end of the scroll, is sent to the storage chamber, is discharged after being heated and then enters the gas compressor 201, hot exhaust gas is at the hot end, and is cooled by a cooler 2031 and then enters the gas compressor 201.

The system 100A of fig. 3 differs from the system of fig. 1 in that the refrigerant compression system cools the gas compressor inlet air at 1012 to improve compression efficiency.

The system 200A of fig. 4 differs from that of fig. 2 in that the scroll hot end exhaust is not introduced to the compressor inlet, which requires air make-up from the environment.

The system 200B of fig. 5 differs from that of fig. 2 in that the scroll cold end discharge gas is not directed into the storage chamber, but rather is passed into the storage chamber heat exchanger 2051 where it is warmed and discharged into the gas compressor.

The difference between the system 200C of fig. 6 and fig. 2 is that the enclosure of the storage room further comprises an exhaust heat exchanger 2052, and the gas exhausted from the storage room is exhausted after the exhaust heat exchanger 2052 absorbs heat, so that the cooling capacity of the exhaust gas at the cold end of the scroll can be greatly increased.

The system 300 shown in fig. 7 is an energy storage refrigeration system, compressed air stored in an air storage tank is used as power of a scroll for refrigeration, the system comprises an air storage tank 301, a refrigerant compression system 302, a scroll 303, a gas pipeline 304, a storage chamber 305 and an exhaust heat exchanger 3051, the refrigerant compression system is a universal system, compressed air is cooled through an evaporator 3021 of the refrigerant compression system, then enters the scroll 303, cold gas is obtained at the cold end of the scroll, and is sent into the storage chamber 305, and the cold gas is heated and then discharged through the exhaust heat exchanger 3051.

The system 200D of fig. 8 differs from that of fig. 2 in that two

refrigerant compression systems

202A and 202B are employed, with the addition of a discharge heat exchanger 2051.

The difference between the system 200D of fig. 9 and fig. 2 is that an exhaust heat exchanger 2051 is added to the enclosure, and a refrigerant heat exchanger 2052 is added, and the refrigerant heat exchanger is connected to a refrigerant compression system, and the refrigerant heat exchanger can effectively reduce the refrigeration load of the scroll.

The system of fig. 10 is a conventional cold storage room keeping mode, and for a low temperature storage room with a temperature of-70 ℃, in order to counteract the heat transfer from the outdoor environment, such as the environment with a temperature of 20 ℃, to the low temperature environment, the quality of cold provided by the conventional mode requires that the temperature is below-70 ℃, such as-70 ℃ to-80 ℃ in the drawing, and the mode of cold provided by the conventional mode and the cold air directly enter the storage room or cold fluid enters a heat exchanger in the storage room is shown in the drawing.

Fig. 11 shows that the new insulation method of the present invention provides a small portion of the cold energy with a quality lower than-70 c and a large portion with a temperature between the storage room temperature and the ambient temperature, as shown in the figure, at-80 c to 10 c or-80 c to-40 c, for the same low temperature storage room at-70 c and the environment at 20 c.

Fig. 12 shows a system 400 comprising a gas compressor 401, a refrigerant compression refrigeration system 402, a scroll 403, a gas pipe 404, a reservoir 405, the refrigerant compression system comprising a first evaporator 4021, a second evaporator 4031, a third evaporator 4032, a fourth evaporator 4052, a refrigerant compressor 4022, a condenser 4023, a throttling device 4024, a refrigerant pipe, etc., 4021 being located at an outlet of the gas compressor 401 and connected to an inlet of the scroll 403 for cooling compressed gas entering the scroll 403, the second evaporator 4031 being located outside the scroll 403 for cooling an outer wall of the scroll, the third evaporator 4032 being located inside the scroll for cooling gas inside the scroll, the fourth evaporator 4052 being located inside an enclosure for cooling gas inside the enclosure, the exhaust heat exchanger being provided for recovering exhaust cold. The gas compressor 401 and scroll 403 form a refrigeration assembly with the refrigerant compression system 402 for refrigerating the storage chamber 405.

The inlet air is compressed by the gas compressor 401, cooled by 4021, and then enters the scroll 403, the cold end of the scroll obtains cold gas, the cold gas is sent to the storage chamber 405, the cold gas is heated by 4051 and then discharged to enter the gas compressor 401, the hot end is hot exhaust gas, and the exhaust gas is cooled by the third evaporator 4032 and then enters the gas compressor 401.

The system 400A in fig. 13 is added with a system 406 including a fan 4061, a pipeline 4062 and a valve 4063 on the basis of the system in fig. 12, and the system is connected with an evaporator 4021, that is, the system can drive a storage chamber to refrigerate by the fan 4061 when an air compressor does not work, and the refrigerant compressor system is operated to refrigerate rapidly when the temperature is high when the storage chamber is started, so that the time for cooling the system is shortened, but after the storage chamber reaches a certain low temperature, the air compressor is started by switching the valve, the fan is stopped, and a lower refrigeration temperature is obtained by a scroll and the refrigerant compression system. FIG. 13 omits the chiller 4032 within the scroll.

The system 400B of fig. 14 differs from the system of fig. 12 in that two gas compressors, 401A and 401B, are used, and can be switched by valves (not shown) to operate in series, in parallel, or independently, and has two advantages, one is to increase the cooling capacity when necessary, and when starting, the other is to achieve a lower temperature by series connection, so that the applicable temperature range of the refrigerating chamber is larger, and the third is to improve the reliability, and one compressor can be used for standby.

The system 400C of fig. 15 adds a compressed gas self-cooler 407 to that of fig. 14 to cool the scroll inlet with a portion of the scroll cold end gas, which results in a lower cold end temperature for the scroll.

The system 500 of fig. 16 is a refrigeration combination of two scrolls which exchange heat via a gas/gas cooler 501, so that the scrolls of the refrigeration combination 2 can obtain lower temperatures for refrigeration, and in the figure, for refrigeration of a storage chamber. In the figure, two scrolls are provided with two refrigerant compression systems, and the two scrolls can also share one refrigerant compression system.

The system 500A of fig. 17 adds a compressed gas auto-cooler 502 to the system of fig. 15 to achieve a lower cooling temperature than the system 500.

The system 600 of fig. 18 is added with a high temperature storage room 601 in addition to the system 400, and the original low temperature storage room 405 is placed in the 601, and the evaporator 4052 is placed in the enclosure of 601.

The two storerooms can realize storage at two temperatures, and the low-temperature storeroom is arranged in the high-temperature storeroom, so that heat preservation and energy conservation are facilitated.

Fig. 19 is a system 700 further optimized from the system of fig. 18, which includes a scroll external cooler integrated with a scroll intake air cooler, and the like, the system 700 includes a gas compressor 701, a refrigerant compression system 702, a scroll 703, a gas pipe 704, a low temperature storage chamber 705, a high temperature storage chamber 706, a fan 707, an air pipe 708, and the like, the refrigerant compression system 702 includes a throttling device 7021, a condenser 7022, a refrigerant compressor 7023, a first evaporator 70241, which is a cooler integrated with the scroll external cooler and the scroll intake air cooler, a second evaporator 70242, which is a scroll internal cooler connected to 70241 and not shown in the figure, a third evaporator 7025, which is an air cooler, a refrigerant pipe 7026, during operation, liquid refrigerant from the throttling device 7021 passes through 70241 and 70242, and then passes through 7025, the refrigerant is evaporated into a gas phase, then is compressed by the compressor 7023, and then is cooled into a liquid phase by the condenser 7022, and then passes through a throttling device 7021 to complete a cycle, and the refrigerant pipes are connected with each part in the sequence to form a refrigerant compression system 702. The enclosure 7051 of the low-temperature storage chamber 705 is a heat-insulating structure with a heat exchange function, and comprises a porous heat-insulating core 70511 (such as perlite or aerosol) with

gas channels

70512 and 70513 on two sides.

The refrigeration process is as follows, the gas is compressed by the gas compressor 701, then cooled by the first evaporator 70241, the cooled gas enters the scroll 703, the scroll 703 is cooled by 70241 and 70242 at the same time, the gas which is further cooled at the cold end of the scroll enters the gas passage 70512 of the enclosure 7051 of the low-temperature storage chamber 705, then passes through the porous body thermal insulation core 70511 and enters the gas passage 70513, the gas is heated in 705, and the gas discharged 705 is mixed with the gas discharged from the hot end of the scroll and then enters the gas compressor 701.

Meanwhile, the fan 707 drives the air from the high-temperature storage chamber 706 to pass through the third evaporator 7025, and the cooled air is returned to the high-temperature storage chamber 706, so that the air is continuously circulated to cool the high-temperature storage chamber 706.

When the storage chamber is started, the gas compressor 701 does not need to be started, only the refrigerant compression system 702 needs to be started, the first evaporator 70241 and the second evaporator 70242 do not need to provide refrigeration, the third evaporator 7025 provides refrigeration and provides large cold, namely the total cold of 3 evaporators quickly cools the high-temperature storage chamber 706 to reach the specified temperature, and after the high-temperature storage chamber 706 reaches the temperature, the gas compressor 701 is started again, the refrigerant compression system 702 and the scroll 703 jointly refrigerate, the low-temperature storage chamber 705 is cooled, and the high-temperature storage chamber 706 is kept cold. Due to the special structure of the enclosure of the low temperature storage chamber 705, namely, the enclosure has a heat exchange function, the enclosure of the low temperature storage chamber can be quickly cooled, so that the low temperature storage chamber 705 can quickly reach the designated temperature. The large amount of cold causes rapid cooling of the high temperature storage compartment 706, and rapid cooling of the particular enclosure of the low temperature enclosure, both of which result in the storage compartment of the present invention being able to reach a specified temperature quickly. The conventional low-temperature refrigerator has no large cold quantity, does not have the enclosure of a heat exchange structure, and has long starting time, for example, the time from starting to reaching the temperature of the refrigerator with the temperature of 70 ℃ below zero is as long as 6.5 hours, which seriously influences the use convenience of a user.

In fact, the volume in the low-temperature refrigerator is generally small, the air quantity is small, the main load is the enclosure when the low-temperature refrigerator is started, the enclosure is made of more heat insulation materials and needs a long time to be cooled down, and the novel enclosure structure, namely the heat insulation structure with the heat exchange function, has obvious advantages and other benefits, as described above.

The double storage chamber structure and the low-temperature enclosure structure of the invention bring another advantage of effectively reducing frost generation, because the temperature of the gas flowing through the enclosure of the low-temperature storage chamber has gradient, the temperature of the gas in 70513 is close to the temperature of the high-temperature storage chamber 706, the exterior of the low-temperature storage chamber, namely the high-temperature storage chamber, can not frost, but the freezing chamber and the refrigerating chamber of the existing refrigerator are usually prevented from dewing by heating the partition wall between the freezing chamber and the refrigerating chamber, in addition, for the interior of the low-temperature chamber, because the high-temperature storage chamber 706 is separated when the door is opened, the ambient air can not be directly introduced, and the frost formation is less than that of the ordinary low-temperature refrigerator.

For defrosting and cleaning, the invention can improve high-temperature compressed air through the scroll to rapidly defrost and clean, namely, when defrosting, the hot air of the scroll is utilized to cut off cold air, and the conversion can be realized by arranging a valve in the system, wherein the valve is not shown in the figure.

The system 700B of fig. 20 is adapted to be smaller than the system 700 of fig. 19, and serves as an enclosure for the low temperature compartment only, and does not store anything else, which is suitable for situations where only low temperature storage is required.

The benefits of the present invention can be further demonstrated by the following examples.

As in the cryogenic refrigerator of fig. 20, the refrigerating capacity is assumed to be 130W, wherein the air system provides 86.5W, the compressed gas system provides 43.5W, and the cryogenic storage temperature is-70 ℃. The high temperature storage chamber is at-40 deg.C, the ambient temperature is 20 deg.C, and the required compressed air flow is 3.6m³The pressure of compressed gas is 0.2MPa, the compressed air enters a low-temperature storage chamber at a low temperature of-94 ℃, is discharged at a temperature of-44 ℃, consumes 241W of power of a gas compressor, consumes 300W of power of a refrigerant compression system, consumes 541W of common power, and has a system COP of 24 percent (130/540), while the conventional overlapping refrigerant compression system consumes 2600W of power and about 5 percent of COP, while the Stirling system consumes 1600W of power and about 8 percent of COP, and the system of the invention only consumes 1/3-1/5 of the system.

The above examples show that the system can save energy greatly, and at the same time, because of using the conventional refrigeration compressor and low-pressure small-flow gas compressor, the pressure is only 0.2MPa, and the flow is 3.6m³And h, the reliability is greatly improved, and the cost is greatly reduced.

Claims

1. A low-temp refrigerating method features that the compressed gas is cooled by refrigerant compression-type refrigerating system or other cold source and used as the inlet gas of vortex tube, the low-temp exhaust gas at cold end of vortex tube is used for refrigerating, and the vortex tube and refrigerant compression-type refrigerating system or other cold source can run simultaneously or sequentially.

2. The method as claimed in claim 1, wherein the refrigerant compression type refrigerating system or other cold source is also used for cooling the scroll pipe at the same time, so as to improve the efficiency and refrigerating capacity of the scroll pipe; or after the low-temperature exhaust at the cold end of the scroll pipe completes the refrigeration purpose, part or all of the low-temperature exhaust returns to the inlet of the gas compressor and enters the gas compressor; or the exhaust gas at the hot end is partially or completely reused, namely, the exhaust gas at the hot end is partially or completely returned to the inlet of the gas compressor to enter the gas compressor, the exhaust gas of the gas compressor is cooled by a refrigerant compression type refrigerating system or other cold sources and then is used as the inlet gas of the scroll, and the cooling is carried out by utilizing the cold energy provided by the refrigerant compression type refrigerating system or utilizing other cold sources.

3. The method of claim 1 further including providing a lower temperature discharge at the cold end of the scroll by one or a combination of:

4. A low-temperature refrigerating system is characterized by comprising a gas compressor, a scroll and a compressed gas cooling device, wherein an outlet of the gas compressor is connected with an inlet of the compressed gas cooling device through a gas pipeline; the compressed gas cooling device is a secondary refrigerant heat exchanger and a refrigerant compression refrigerating system.

5. A cryogenic refrigeration system according to claim 4, further comprising a scroll cooler for cooling the outer wall of the scroll and/or the gas in the scroll, the scroll cooler being cooled by the refrigerant or coolant of the refrigerant compression refrigeration system, the scroll cooler being located within the scroll and/or outside the scroll or being integral with the compressed gas cooling means. Or the inlet of the gas compressor is connected with one or more of the environment, the exhaust port of the device refrigerated by the low-temperature refrigeration system and the exhaust port at the hot end of the scroll. The gas compressor exhaust port is provided with a radiator, or the low-temperature refrigeration system is also matched with a gas storage tank, and the gas storage tank is connected with a hot fluid inlet of the compressed gas cooling device.

6. An energy storage low-temperature refrigeration system is characterized by comprising an air storage tank, a scroll pipe and a compressed air cooling device, wherein an outlet of the air storage tank is connected with an inlet of the compressed air cooling device; the compressed air cooling device is a secondary refrigerant heat exchanger or a refrigerant compression refrigeration system.

7. The energy-storing cryogenic refrigeration system of claim 6, further comprising a scroll cooler for cooling the outer wall of the scroll and/or the gas in the scroll, wherein the scroll cooler is cooled by the refrigerant or coolant of the refrigerant compression refrigeration system, and wherein the scroll cooler is located inside the scroll and/or outside the scroll, or is integrated with the compressed gas cooling device. Or the system is also matched with an air compressor which is connected with the inlet of the compressed air cooling device.

8. The scroll with the cooler is characterized in that the cooler comprises one or more coolers for cooling the outer wall of the scroll, gas in the scroll and air intake of the scroll, wherein the coolers for cooling the outer wall of the scroll and air intake of the cooling pipe are arranged outside the scroll, the cooler for cooling the gas in the scroll is arranged inside the scroll, and the cooler adopts a refrigerant or a secondary refrigerant of a refrigerant compression refrigeration system to refrigerate.

9. A cryogenic storage system comprising a storage compartment and a cryogenic refrigeration system according to claim 4 or an energy storage cryogenic refrigeration system according to claim 6 for refrigerating the storage compartment, including refrigeration of refrigerators, freezers and the like.

10. A low-temperature storage system is characterized by comprising a gas compressor, a refrigerant compression system, a scroll, a low-temperature storage chamber, a high-temperature storage chamber and a fan, wherein the refrigerant compression system comprises a throttling device, a condenser, a refrigerant compressor, a first evaporator and a third evaporator. The low-temperature storage chamber is arranged in the high-temperature storage chamber, and the high-temperature storage chamber is used for storing articles or used as an enclosure of the low-temperature storage chamber. The outer wall of the low-temperature storage chamber is further provided with a heat insulation structure, a porous heat insulation core body is filled in the heat insulation structure, a first gas channel and a second gas channel are arranged on two sides of the heat insulation core body, the first gas channel is in contact with the outer wall of the low-temperature storage chamber, and the second gas channel is located on the outermost side of the low-temperature storage chamber. The first evaporator is arranged on the outer wall of the scroll, the outlet of the throttling device is connected with the refrigerant inlet of the first evaporator, the refrigerant outlet of the first evaporator is connected with the refrigerant inlet of the third evaporator, the refrigerant outlet of the third evaporator is connected with the inlet of the compressor, the outlet of the compressor is connected with the inlet of the condenser, and the outlet of the condenser is sequentially connected with the inlet of the throttling device to form a refrigerant compression system. The outlet of the gas compressor is connected with the compressed air inlet of the first evaporator, the compressed air outlet of the first evaporator is connected with the air inlet of the scroll, the cold end outlet of the scroll is connected with the inlet of the first gas passage of the low-temperature storage chamber, and the outlet of the second gas passage and the outlet of the hot end of the scroll are simultaneously connected with the inlet of the gas compressor; the air inlet and outlet of the high-temperature storage chamber, the air inlet and outlet of the third evaporator and the fan are sequentially connected to form circulation, so that the refrigerant of the high-temperature storage chamber is cooled by the third evaporator, or the second evaporator is arranged in the scroll and is connected with the first evaporator in series or in parallel.