CN114279126A - Cryogenic treatment and cold energy recovery system and method - Google Patents

Abstract

The invention relates to the technical field of cryogenic treatment, in particular to a cryogenic treatment and cold recovery system and a method, wherein the cryogenic treatment and cold recovery system comprises a low-temperature treatment device and a cold recovery device, and a first exhaust port of the low-temperature treatment device, a first air inlet of the cold recovery device, a second exhaust port of the cold recovery device and a second air inlet of the low-temperature treatment device are communicated in sequence to form a first cold circulation loop; and a third exhaust port of the cold energy recovery device, a third air inlet of the low-temperature treatment device, a fourth exhaust port of the low-temperature treatment device and a fourth air inlet of the cold energy recovery device are communicated in sequence to form a second cold energy circulation loop. The low-temperature treatment device and the cold energy recovery device are connected through a cold energy circulation pipeline to form a closed circulation system, so that the cold energy is completely recovered.

Description

Cryogenic treatment and cold energy recovery system and method

Technical Field

The invention relates to the technical field of cryogenic treatment, in particular to a cryogenic treatment and cold energy recovery system and method.

Background

At present, cryogenic treatment technologies (such as cold treatment of metal materials, low-temperature quick freezing of foods and the like) generally utilize liquid nitrogen as a refrigeration working medium to carry out cryogenic treatment on materials so as to improve the properties of the materials (such as the wear resistance and the dimensional stability of the metal materials and the storage time of the foods). In the cryogenic treatment process, liquid nitrogen is sprayed into the low-temperature treatment device, is gasified after absorbing heat, and is discharged to the environment at the temperature which is not higher than the material treatment temperature, so that a large amount of cold loss exists.

Aiming at the problem of cold loss in direct evacuation of low-temperature nitrogen, the prior art generally recovers cold of discharged low-temperature nitrogen by using a phase-change material, and returns the cold to a low-temperature treatment device by using heat exchange equipment when needed, thereby reducing the energy consumption of the system. But the actual exhaust temperature after passing through the cold energy recovery device is still lower than the room temperature, and the cold energy is difficult to recover by hundreds. In addition, the cold energy recovery device is discontinuous, and in the cold energy utilization process, the working medium gas introduced into the cold energy recovery device needs to be subjected to dehumidification and other treatments or additionally adopts nitrogen, so that the difficulty and the cost of operation are increased.

Disclosure of Invention

The present invention is directed to solving at least one of the problems of the prior art. Therefore, the invention provides a cryogenic treatment and cold recovery system, which connects a cryogenic treatment device and a cold recovery device through a cold circulation pipeline to form a closed circulation system, thereby realizing the complete recovery of cold.

The invention also provides a cryogenic treatment and cold energy recovery method.

According to the cryogenic treatment and cold recovery system of the embodiment of the first aspect of the invention, the system comprises a low-temperature treatment device and a cold recovery device, wherein a first exhaust port of the low-temperature treatment device, a first air inlet of the cold recovery device, a second exhaust port of the cold recovery device and a second air inlet of the low-temperature treatment device are communicated in sequence to form a first cold circulation loop; and the third exhaust port of the cold energy recovery device, the third air inlet of the low-temperature treatment device, the fourth exhaust port of the low-temperature treatment device and the fourth air inlet of the cold energy recovery device are communicated in sequence to form a second cold energy circulation loop.

According to one embodiment of the invention, the cryogenic treatment device comprises a cryogenic box and a cooling assembly, the first air inlet and the third air inlet are both located at the top of the cryogenic box, the second air inlet and the fourth air outlet are both located at the bottom of the cryogenic box, and the cooling assembly is arranged in the cryogenic box and located on one side of the cryogenic box close to the second air inlet.

According to an embodiment of the present invention, the cold energy recovery device includes a cold storage box and a cold storage material filled in the cold storage box, the first air inlet and the third air outlet are both located at the top of the cold storage box, and the second air outlet and the fourth air inlet are both located at the bottom of the cold storage box.

According to one embodiment of the invention, the cold supply assembly comprises a fan, a disperser and a liquid nitrogen tank, the liquid nitrogen tank is connected with the disperser, the fan and the disperser are both positioned in the cryogenic box, and the fan is positioned below the disperser.

According to one embodiment of the invention, the cryogenic tank above the disperser is used for filling with material to be treated cold.

According to one embodiment of the present invention, the top of the interior of the cryogenic box is provided with a first temperature detector, and the top and the bottom of the interior of the cold storage box are provided with a second temperature detector.

According to one embodiment of the invention, a first exhaust valve is arranged at the first exhaust port, a first intake valve is arranged at the first exhaust port, a second exhaust valve is arranged at the second exhaust port, and a second intake valve is arranged at the second intake port.

According to one embodiment of the invention, a third exhaust valve is arranged at the third exhaust port, a third intake valve is arranged at the third intake port, a fourth exhaust valve is arranged at the fourth exhaust port, and a fourth intake valve is arranged at the fourth intake port.

According to an embodiment of the present invention, a branch pipeline is disposed on a pipeline of the second exhaust port communicating with the second air inlet, and a pressure release valve is disposed on the branch pipeline.

According to the second aspect of the embodiment of the invention, the method for cryogenic treatment and cold recovery by using the cryogenic treatment and cold recovery system comprises the following steps:

primary cooling treatment:

the liquid nitrogen supply is started, the fan rotates forwards, the second cold energy circulation loop is closed, the communication pipeline between the first exhaust port of the low-temperature treatment device of the first cold energy circulation loop and the first air inlet of the cold energy recovery device is opened, the communication pipeline between the second exhaust port of the cold energy recovery device and the second air inlet of the low-temperature treatment device is closed, and the branch pipeline communicated with the second exhaust port is opened;

when the temperature of the middle part of the cold storage material in the cold storage recovery device is lower than the preset temperature, a branch pipeline communicated with a second exhaust port is closed, the supply of liquid nitrogen is stopped, the fan is reversed, a second cold storage circulation loop is opened, and a first cold storage circulation loop is closed;

first cold circulation treatment:

when the temperature of the top of the cold storage material in the cold energy recovery device is higher than the temperature in the low-temperature treatment device, the fan rotates forwards, the first cold energy circulation loop is opened, and the second cold energy circulation loop is closed;

and (3) second cold circulation treatment:

when the temperature of the bottom of the cold storage material in the cold energy recovery device is higher than the temperature in the low-temperature treatment device, the fan rotates reversely, the first cold energy circulation loop is closed, and the second cold energy circulation loop is opened;

and the first cold circulation treatment and the second cold circulation treatment are alternately and circularly carried out in sequence.

One or more technical solutions in the embodiments of the present invention at least have the following technical effects: the cryogenic treatment and cold energy recovery system provided by the embodiment of the invention aims at the problems that the existing cryogenic treatment device cannot completely recover the cold energy of the cooling medium, the operation difficulty in the cold energy recovery process is high, the cost is high and the like, and provides the cryogenic treatment device capable of recycling the cold energy of the cooling medium. The low-temperature treatment device and the cold energy recovery device are connected through a cold energy circulation pipeline to form a closed circulation system, so that the cold energy is completely recovered. Two mutually independent first cold circulation loops and second cold circulation loops are formed through two groups of air inlets and two groups of air outlets which are respectively arranged on the low-temperature treatment device and the cold recovery device, and the flow direction of a cooling medium in the first cold circulation loop is opposite to the flow direction of the cooling medium in the second cold circulation loop. The first cold energy circulation loop enables the material to be cold treated to exchange heat with the low-temperature medium in the low-temperature treatment device, and the gasified low-temperature cooling medium enters the cold energy recovery device, so that the cold energy is completely recovered in the cold energy recovery device and the cooling medium is discharged, or the material to be cold treated returns to the low-temperature treatment device after being subjected to heat exchange and temperature reduction in the cold energy recovery device; the second cold circulation loop enables the cooling medium in the low-temperature treatment device to enter the cold recovery device and carry out heat exchange and temperature reduction with the cold recovered in the cold recovery device, so that the cooling medium returns to the low-temperature treatment device again to carry out heat exchange with the material to be cold treated, and the consumption of the cooling medium is greatly reduced.

In addition to the technical problems addressed by the present invention, the technical features constituting the technical solutions and the advantages brought by the technical features of the technical solutions described above, other technical features of the present invention and the advantages brought by the technical features of the present invention will be further described with reference to the accompanying drawings or will be understood by the practice of the present invention.

Drawings

In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the drawings used in the description of the embodiments or the prior art will be briefly described below, it is obvious that the drawings in the following description are only some embodiments of the present invention, and for those skilled in the art, other drawings can be obtained according to the drawings without creative efforts.

FIG. 1 is a schematic structural diagram of a cryogenic treatment and cold recovery system according to an embodiment of the present invention.

Reference numerals:

1: a low-temperature processing device; 11: a cryogenic box; 12: a cooling assembly; 111: a first temperature detector; 121: a fan; 122: a disperser; 123: a liquid nitrogen tank; 124: a liquid nitrogen control valve; 125: a motor;

2: a cold energy recovery device; 21: a cold storage tank; 22: a cold storage material; 211: a second temperature detector;

31: treating the material to be cooled;

41: a first exhaust valve; 42: a second exhaust valve; 43: a third exhaust valve; 44: a fourth exhaust valve;

51: a first intake valve; 52: a second intake valve; 53: a third air inlet valve; 54: a fourth intake valve;

61: a first pipeline; 62: a second pipeline; 63: a third pipeline; 64: a fourth pipeline;

7: a branch pipeline; 71: and (4) releasing the valve.

Detailed Description

The embodiments of the present invention will be described in further detail with reference to the drawings and examples. The following examples are intended to illustrate the invention but are not intended to limit the scope of the invention.

In the description of the embodiments of the present invention, it should be noted that the terms "center", "longitudinal", "lateral", "upper", "lower", "front", "rear", "left", "right", "vertical", "horizontal", "top", "bottom", "inner", "outer", and the like indicate orientations or positional relationships based on those shown in the drawings, and are only for convenience in describing the embodiments of the present invention and simplifying the description, but do not indicate or imply that the referred devices or elements must have a specific orientation, be constructed in a specific orientation, and be operated, and thus, should not be construed as limiting the embodiments of the present invention. Furthermore, the terms "first," "second," and "third" are used for descriptive purposes only and are not to be construed as indicating or implying relative importance, nor is it to be construed as representing any order or degree.

In the description of the embodiments of the present invention, it should be noted that, unless explicitly stated or limited otherwise, the terms "connected" and "connected" are to be interpreted broadly, and may be, for example, fixedly connected, detachably connected, or integrally connected; can be mechanically or electrically connected; may be directly connected or indirectly connected through an intermediate. Specific meanings of the above terms in the embodiments of the present invention can be understood in specific cases by those of ordinary skill in the art.

In embodiments of the invention, unless expressly stated or limited otherwise, the first feature "on" or "under" the second feature may be directly contacting the first and second features or indirectly contacting the first and second features through intervening media. Also, a first feature "on," "over," and "above" a second feature may be directly or diagonally above the second feature, or may simply indicate that the first feature is at a higher level than the second feature. A first feature being "under," "below," and "beneath" a second feature may be directly under or obliquely under the first feature, or may simply mean that the first feature is at a lesser elevation than the second feature.

In the description herein, references to the description of the term "one embodiment," "some embodiments," "an example," "a specific example," or "some examples," etc., mean that a particular feature, structure, material, or characteristic described in connection with the embodiment or example is included in at least one embodiment or example of an embodiment of the invention. In this specification, the schematic representations of the terms used above are not necessarily intended to be the same embodiment or example. Furthermore, the particular features, structures, materials, or characteristics described may be combined in any suitable manner in any one or more embodiments or examples. Furthermore, various embodiments or examples and features of different embodiments or examples described in this specification can be combined and combined by one skilled in the art without contradiction.

As shown in fig. 1, the cryogenic treatment and cold recovery system provided in the embodiment of the present invention includes a low-temperature treatment device 1 and a cold recovery device 2, wherein a first exhaust port of the low-temperature treatment device 1, a first air inlet of the cold recovery device 2, a second exhaust port of the cold recovery device 2, and a second air inlet of the low-temperature treatment device 1 are sequentially communicated to form a first cold circulation loop; and a third exhaust port of the refrigeration capacity recovery device 2, a third air inlet of the low-temperature treatment device 1, a fourth exhaust port of the low-temperature treatment device 1 and a fourth air inlet of the refrigeration capacity recovery device 2 are communicated in sequence to form a second refrigeration capacity circulation loop.

The cryogenic treatment and cold energy recovery system provided by the embodiment of the invention aims at the problems that the existing cryogenic treatment device cannot completely recover the cold energy of the cooling medium, the operation difficulty in the cold energy recovery process is high, the cost is high and the like, and provides the cryogenic treatment device capable of recycling the cold energy of the cooling medium. The low-temperature treatment device 1 and the cold energy recovery device 2 are connected through a cold energy circulation pipeline to form a closed circulation system, so that the whole recovery of cold energy is realized. Two mutually independent first cold energy circulation loops and second cold energy circulation loops are formed through two groups of air inlets and two groups of air outlets which are respectively arranged on the low-temperature treatment device 1 and the cold energy recovery device 2, and the flow direction of a cooling medium in the first cold energy circulation loop is opposite to the flow direction of the cooling medium in the second cold energy circulation loop. The first cold energy circulation loop enables the material 31 to be cold treated to exchange heat with the cooling medium in the low-temperature treatment device 1, the gasified low-temperature cooling medium enters the cold energy recovery device 2, the cold energy is completely recovered in the cold energy recovery device 2, and the cooling medium is discharged, or the material is returned to the low-temperature treatment device 1 after heat exchange and temperature reduction are carried out in the cold energy recovery device 2; the second cold circulation loop enables the cooling medium in the low-temperature treatment device 1 to enter the cold recovery device 2 and carry out heat exchange with the cold recovered in the cold recovery device 2 for cooling, so that the cooling medium returns to the low-temperature treatment device 1 again to carry out heat exchange with the material 31 to be cooled, and the consumption of the cooling medium is greatly reduced.

According to one embodiment of the present invention, the cryogenic processing device 1 includes a cryogenic tank 11 and a cooling module 12, wherein the first air inlet and the third air inlet are located at the top of the cryogenic tank 11, the second air inlet and the fourth air outlet are located at the bottom of the cryogenic tank 11, and the cooling module 12 is disposed in the cryogenic tank 11 and located at a side of the cryogenic tank 11 close to the second air inlet. The cold energy recovery device 2 comprises a cold storage box 21 and a cold storage material 22 filled in the cold storage box 21, the first air inlet and the third air outlet are both positioned at the top of the cold storage box 21, and the second air outlet and the fourth air inlet are both positioned at the bottom of the cold storage box 21.

In this embodiment, the cryogenic tank 11 is vertically disposed, the flow direction of the cooling medium in the cryogenic tank is from top to bottom or from bottom to top, and the cooling component 12 provides the cooling medium for the cold circulation of the cryogenic treatment device 1 and the whole system. The cold storage box 21 is also vertically arranged, the cold storage material 22 is filled in the cold storage box, and the cooling medium exchanges heat with the cold storage material 22 and enters and exits from the top or the bottom of the cold storage box 21.

In the first refrigeration capacity circulation loop, after heat exchange between the cooling medium and the material 31 to be refrigerated, the cooling medium is discharged from the first exhaust port at the top of the cryogenic box 11, enters the cold storage box 21 through the first air inlet at the top of the cold storage box 21 after passing through the first pipeline 61, is discharged from the second exhaust port at the bottom of the cold storage box 21 after passing through the heat exchange with the cold storage material 22, and enters the cryogenic box 11 through the second air inlet at the bottom of the cryogenic box 11 after passing through the second pipeline 62 to exchange heat with the material 31 to be refrigerated.

In the second refrigeration capacity circulation loop, the cooling medium is discharged from the fourth exhaust port at the bottom of the cryogenic tank 11, enters the cold storage tank 21 through the fourth air inlet at the bottom of the cold storage tank 21 after passing through the third pipeline 63, is discharged from the third exhaust port at the top of the cold storage tank 21 after passing through the heat exchange with the cold storage material 22, enters the cryogenic tank 11 through the third air inlet at the top of the cryogenic tank 11 after passing through the fourth pipeline 64, and exchanges heat with the material 31 to be refrigerated.

In this embodiment, the cold storage box 21 is an external cavity with a thermal insulation material, and the thermal insulation material is selected from a polyurethane foam material and the like. The cold storage material 22 is a solid cold storage material or a phase change cold storage material for recovering cold energy of low-temperature nitrogen, and the cold storage material 22 may be a low-temperature solid cold storage material made of materials such as stone, stainless steel, copper, and the like, such as silk screen, particles, and the like, or a phase change cold storage material such as carbon dioxide, ammonia, and the like.

According to an embodiment of the present invention, the cooling supply assembly 12 includes a blower 121, a disperser 122, and a liquid nitrogen tank 123, the liquid nitrogen tank 123 is connected to the disperser 122, the blower 121 and the disperser 122 are both located in the cryogenic box 11, and the blower 121 is located below the disperser 122. In this embodiment, the cooling medium is provided by the liquid nitrogen, and fan 121 is located the inside bottom of cryogenic box 11, and deconcentrator 122 is installed to fan 121 top, and liquid nitrogen container 123 passes through liquid nitrogen conveying pipe and connects deconcentrator 122 to this carries out the homodisperse to the liquid nitrogen, and low temperature nitrogen gas passes through fan 121 control flow direction. When the fan 121 rotates forward, low-temperature nitrogen flows in the first cold capacity circulation loop, and when the fan 121 rotates backward, low-temperature nitrogen flows in the second cold capacity circulation loop.

In this embodiment, a liquid nitrogen control valve 124 is disposed on a liquid nitrogen delivery pipeline connecting the liquid nitrogen tank 123 and the disperser 122, so as to control the input time and flow rate of the liquid nitrogen. The fan 121 is connected by an external motor 125, so as to control the start, stop and turning of the fan 121.

In this embodiment, the cooling medium may be other cryogenic liquid such as liquid argon. In the cold quantity recycling and utilizing process, the low-temperature nitrogen in the system is used as the working medium, so that the problems of high cost caused by the fact that the existing equipment needs to absorb outside air as the working medium to perform dehumidification and the like or the existing equipment needs to additionally introduce dry nitrogen as the working medium are solved.

According to one embodiment of the invention, the cryogenic box 11 above the disperser 122 is used to fill the material to be treated 31. In this embodiment, the disperser 122 is a plate-shaped structure, and divides the internal space of the cryogenic box 11 into two parts from top to bottom, the upper part of the space is used for filling the material 31 to be cooled, and the lower part of the space is provided with the fan 121. The deconcentrator 122 disperses the liquid nitrogen, because the fan 121 is below the deconcentrator 122, the liquid nitrogen can flow upward and evenly contact the material 31 to be cooled in the upper part of the space after the fan 121 rotates, the liquid nitrogen absorbs heat and gasifies to form low-temperature nitrogen after heat exchange, the liquid nitrogen continues to move upward under the action of the fan 121 to enter the first exhaust port, or the nitrogen entering the deep cooling box 11 through the third air inlet contacts the material 31 to be cooled in the upper part of the space, and the nitrogen is discharged to the cold energy recovery device 2 through the fourth exhaust port under the action of the fan 121 after heat exchange.

According to an embodiment of the present invention, the first temperature detector 111 is provided at the top inside the cryogenic box 11, and the second temperature detector 211 is provided at both the top and bottom inside the cold storage box 21. In this embodiment, the first temperature detector 111 is disposed in the cryogenic tank 11 for detecting the real-time temperature inside the cryogenic tank 11, and the second temperature detector 211 is disposed in the cold storage tank 21 near the top and bottom positions for detecting the real-time temperature inside the cold storage tank 21. The direction of the nitrogen gas circulation can be controlled by the magnitude relation of the detection temperatures of the first temperature detector 111 and the second temperature detector 211. In this embodiment, thermometers are used for the first temperature detector 111 and the second temperature detector 211.

According to one embodiment of the invention, a first exhaust valve 41 is provided at the first exhaust port, a first intake valve 51 is provided at the first intake port, a second exhaust valve 42 is provided at the second exhaust port, and a second intake valve 52 is provided at the second intake port. A third exhaust valve 43 is arranged at the third exhaust port, a third air inlet valve 53 is arranged at the third air inlet port, a fourth exhaust valve 44 is arranged at the fourth exhaust port, and a fourth air inlet valve 54 is arranged at the fourth air inlet port.

In this embodiment, the refrigeration cycle pipeline includes a first pipeline 61, a second pipeline 62, a third pipeline 63, and a fourth pipeline 64 connecting the cryogenic box 11 and the cold storage box 21, which are uniformly disposed outside the cryogenic box 11 and the cold storage box 21, and are respectively provided with a switch valve, that is, the first pipeline 61 connecting the first exhaust port and the first air inlet is correspondingly provided with a first exhaust valve 41 and a first air inlet valve 51, the second pipeline 62 connecting the second exhaust port and the second air inlet is correspondingly provided with a second exhaust valve 42 and a second air inlet valve 52, the third pipeline 63 connecting the fourth exhaust port and the fourth air inlet is correspondingly provided with a fourth exhaust valve 44 and a fourth air inlet valve 54, and the fourth pipeline 64 connecting the third exhaust port and the third air inlet is correspondingly provided with a third exhaust valve 43 and a third air inlet valve 53.

When the first refrigeration circulation circuit is open, i.e. the first exhaust valve 41, the first intake valve 51, the second exhaust valve 42 and the second intake valve 52 are open, when the first refrigeration circulation circuit is closed, these four valves are correspondingly closed; when the second refrigeration circuit is open, i.e. the third outlet valve 43, the third inlet valve 53, the fourth outlet valve 44 and the fourth inlet valve 54 are open, these four valves are correspondingly closed when the second refrigeration circuit is closed.

The outside of each cold circulation pipeline is wrapped with a heat insulation material to reduce the cold loss. When the first refrigeration capacity circulation loop or the second refrigeration capacity circulation loop is operated, the control of the related air inlet valve or exhaust valve can be manual control or automatic control, so that the refrigeration capacity of the low-temperature nitrogen is recycled and utilized.

According to an embodiment of the present invention, a branch pipeline 7 is provided on a pipeline of the second exhaust port communicating with the second intake port, and a pressure relief valve 71 is provided on the branch pipeline 7. In this embodiment, in the process of initial cooling, the cooling module 12 is turned on, after the low-temperature nitrogen gas is formed by heat exchange and gasification of the liquid nitrogen and the material to be cooled, the liquid nitrogen enters the cold storage box 21 from the cryogenic box 11 through the first pipeline, the cooling capacity is stored in the cold storage material 22, and then the cooling capacity is discharged through the pressure release valve 71 of the branch pipeline 7 which is communicated with the second exhaust port at the bottom of the cold storage box 21, so that the cooling capacity of the low-temperature nitrogen gas is recovered in the cooling capacity recovery device 2. That is, the first exhaust valve 41, the first intake valve 51, the second exhaust valve 42, and the relief valve 71 are open, and the second intake valve 52, the third exhaust valve 43, the third intake valve 53, the fourth exhaust valve 44, and the fourth intake valve 54 are closed.

The embodiment of the invention also provides a cryogenic treatment and cold recovery method by applying the cryogenic treatment and cold recovery system of the embodiment, which comprises the following steps:

primary cooling treatment:

the liquid nitrogen supply is started, the fan 121 rotates forwards, the second cold energy circulation loop is closed, the communication pipeline between the first exhaust port of the low-temperature treatment device 1 of the first cold energy circulation loop and the first air inlet of the cold energy recovery device 2 is opened, the communication pipeline between the second exhaust port of the cold energy recovery device 2 and the second air inlet of the low-temperature treatment device 1 is closed, and the branch pipeline 7 communicated with the second exhaust port is opened to exhaust high-temperature gas which is difficult to recycle in the primary cooling process;

when the temperature of the middle part of the cold storage material 22 in the cold energy recovery device 2 is lower than the preset temperature, the branch pipeline 7 communicated with the second exhaust port is closed, the supply of liquid nitrogen is stopped, the fan 121 is reversed, the second cold energy circulation loop is opened, and the first cold energy circulation loop is closed;

first cold circulation treatment:

when the temperature of the top of the cold storage material 22 in the cold recovery device 2 is higher than the temperature in the low-temperature treatment device 1, the fan 121 rotates forward, the first cold circulation loop is opened, and the second cold circulation loop is closed;

and (3) second cold circulation treatment:

when the temperature of the bottom of the cold storage material 22 in the cold recovery device 2 is higher than the temperature in the low-temperature treatment device 1, the fan 121 is reversed, the first cold circulation loop is closed, and the second cold circulation loop is opened;

the first cold circulation treatment and the second cold circulation treatment are alternately and circularly carried out in sequence.

S1, primary cooling:

after liquid nitrogen input from the liquid nitrogen tank 123 is uniformly dispersed by the disperser 122, the fan 121 rotates clockwise, and blows from bottom to top into the deep cooling box 11 to exchange heat with the material 31 to be cooled, the liquid nitrogen absorbs heat of the material 31 to be cooled and then gasifies, gasified low-temperature nitrogen enters the cold storage box 21 through a first pipeline to exchange heat with the cold storage material 22, the cold energy of the low-temperature nitrogen is stored in the cold storage material 22, the temperature of the low-temperature nitrogen gradually rises, and the low-temperature nitrogen is discharged through the pressure release valve 71 arranged at the bottom of the cold storage box 21 after reaching a preset temperature; meanwhile, the temperature of the upper part of the cool storage material 22 gradually decreases, and the temperature is gradually increased from top to bottom, that is, the cool energy is mainly stored in the cool storage material 22 of the upper half part. In this embodiment, the preset temperature is room temperature.

When the temperature of the middle part of the cold accumulation material 22 is lower than the room temperature, the pressure release valve 71 at the bottom of the cold accumulation box 21 is closed, the liquid nitrogen supply of the liquid nitrogen tank 123 is stopped, and simultaneously, the rotation direction of the fan 121 is changed to rotate along the counterclockwise direction. The low-temperature nitrogen flowing out from the bottom of the cryogenic tank 11 enters the cold storage tank 21 through the third pipeline 63 and then exchanges heat through the cold storage material 22 from bottom to top, the low-temperature nitrogen is gradually heated by the cold storage material 22 with high temperature of the lower half portion, the temperature gradually rises, the temperature returns to high temperature at the middle position, and the temperature of the cold storage material 22 with high temperature of the lower half portion is gradually reduced. The nitrogen returning to the high temperature further exchanges heat with the low-temperature cold storage material 22 of the upper half part, the temperature is gradually reduced, the temperature of the cold storage material 22 of the upper half part is gradually increased at the moment, the nitrogen is reduced to the lowest temperature at the top of the cold storage material 22 and then enters the cryogenic box 11 through the fourth pipeline 64 to cool the material 31 to be cooled, and then enters the bottom of the cold storage material 22 in the cold storage box 21 again to sequentially circulate.

S2, first cold circulation process:

when the temperature of the top of the cool storage material 22 in the cool storage box 21 is higher than the temperature in the deep cooling box 11, the direction of the fan 121 is changed to rotate in the clockwise direction. The low-temperature nitrogen flowing out of the top of the cryogenic tank 11 enters the cold storage tank 21 through the first pipeline 61 and then passes through the cold storage material 22 from top to bottom for heat exchange, the low-temperature nitrogen is gradually heated by the cold storage material 22 with high temperature in the upper half part, the temperature gradually rises, the temperature returns to high temperature in the middle position, and the temperature of the cold storage material 22 with high temperature in the upper half part is gradually reduced. The nitrogen gas after replying to the high temperature further exchanges heat with the low temperature cold storage material 22 of the latter half, and the temperature progressively reduces, and the cold storage material 22 of the latter half temperature progressively rises this moment, and nitrogen gas falls to in the cryogenic box 11 through second pipeline 62 after the cold storage material 22 bottom, treats cold treatment material 31 and cools off, then enters the cold storage material 22 top of cold storage box 21 once more, circulates in proper order.

S3, second cold circulation process:

when the temperature of the bottom of the cool storage material 22 in the cool storage box 21 is higher than the temperature in the deep cooling box 11, the direction of the fan 121 is changed to be rotated in the counterclockwise direction. The low-temperature nitrogen flowing out from the bottom of the cryogenic tank 11 enters the cold storage tank 21 through the third pipeline 63 and then exchanges heat with the cold storage material 22 from bottom to top, the low-temperature nitrogen is gradually heated by the cold storage material 22 with high temperature of the lower half portion, the temperature gradually rises, the temperature reaches the highest state at the middle position, and the temperature of the cold storage material 22 with high temperature of the lower half portion is gradually reduced. The nitrogen returning to the high temperature further exchanges heat with the low-temperature cold storage material 22 of the upper half part, the temperature is gradually reduced, the temperature of the cold storage material 22 of the upper half part is gradually increased at the moment, the nitrogen is reduced to the lowest temperature at the top of the cold storage material 22 and then enters the cryogenic box 11 through the fourth pipeline 64 to cool the material 31 to be cooled, and then enters the bottom of the cold storage material 22 of the cold storage box 21 again to sequentially circulate.

The process of S4, step S2 and step S3 are continuously cycled, during which the supply of liquid nitrogen is stopped. The switching of the exhaust valves and the intake valves is an automatic process, and the controller automatically switches according to the temperature in the deep cooling box 11 measured by the first temperature detector 111 and the temperature relationship between the top and the bottom of the cool storage material 22 measured by the second temperature detector 211.

Considering that the low-temperature system inevitably has heat leakage, after long-time operation, if the low-temperature cooling medium coming out of the cold energy recovery device 2 does not reach the preset temperature, certain liquid nitrogen is supplemented into the system to obtain lower temperature. The cold energy of the low-temperature nitrogen is continuously stored and utilized through the first cold energy circulation or the second cold energy circulation, so that the problems that the cold energy of the cold energy recovery device in a single direction cannot be completely recovered, the operation is complex and high in cost in the recovery process and the like are solved.

When in use, the valve is not limited to be a stop valve, an electric valve, an electromagnetic valve or other valves which can be opened and closed.

Finally, it should be noted that: the above examples are only intended to illustrate the technical solution of the present invention, but not to limit it; although the present invention has been described in detail with reference to the foregoing embodiments, it will be understood by those of ordinary skill in the art that: the technical solutions described in the foregoing embodiments may still be modified, or some technical features may be equivalently replaced; and such modifications or substitutions do not depart from the spirit and scope of the corresponding technical solutions of the embodiments of the present invention.

Claims (10)

1. A cryogenic treatment and cold energy recovery system is characterized in that: the device comprises a low-temperature treatment device and a cold energy recovery device, wherein a first exhaust port of the low-temperature treatment device, a first air inlet of the cold energy recovery device, a second exhaust port of the cold energy recovery device and a second air inlet of the low-temperature treatment device are communicated in sequence to form a first cold energy circulation loop; and the third exhaust port of the cold energy recovery device, the third air inlet of the low-temperature treatment device, the fourth exhaust port of the low-temperature treatment device and the fourth air inlet of the cold energy recovery device are communicated in sequence to form a second cold energy circulation loop.

2. The cryogenic treatment and cold recovery system according to claim 1, wherein: cryogenic treatment device includes cryogenic tank and cooling subassembly, first exhaust port with the third gas inlet all is located the top of cryogenic tank, the second gas inlet with the fourth exhaust port all is located the bottom of cryogenic tank, the cooling subassembly set up in the cryogenic tank, and be located be close to in the cryogenic tank one side of second gas inlet.

3. The cryogenic treatment and cold recovery system according to claim 2, wherein: the cold energy recovery device comprises a cold storage box and a cold storage material filled in the cold storage box, the first air inlet and the third air outlet are both located at the top of the cold storage box, and the second air outlet and the fourth air inlet are both located at the bottom of the cold storage box.

4. The cryogenic treatment and cold recovery system according to claim 2, wherein: the cooling component comprises a fan, a disperser and a liquid nitrogen tank, the liquid nitrogen tank is connected with the disperser, the fan and the disperser are both located in the deep cooling box, and the fan is located below the disperser.

5. The cryogenic treatment and cold recovery system according to claim 4, wherein: the deep cooling box above the disperser is used for filling materials to be treated in a cooling mode.

6. The cryogenic treatment and cold recovery system according to claim 3, wherein: the top of the interior of the cryogenic box is provided with a first temperature detector, and the top and the bottom of the interior of the cold storage box are provided with second temperature detectors.

7. The cryogenic treatment and cold recovery system according to any one of claims 1 to 6, wherein: the exhaust valve is characterized in that a first exhaust valve is arranged at the first exhaust port, a first intake valve is arranged at the first intake port, a second exhaust valve is arranged at the second exhaust port, and a second intake valve is arranged at the second intake port.

8. The cryogenic treatment and cold recovery system according to claim 7, wherein: the third exhaust port is provided with a third exhaust valve, the third air inlet is provided with a third air inlet valve, the fourth exhaust port is provided with a fourth exhaust valve, and the fourth air inlet is provided with a fourth air inlet valve.

9. The cryogenic treatment and cold recovery system according to claim 7, wherein: and a branch pipeline is arranged on a pipeline communicated with the second air outlet and the second air inlet, and a pressure release valve is arranged on the branch pipeline.

10. A cryogenic treatment and cold recovery method using the cryogenic treatment and cold recovery system according to any one of claims 1 to 9, characterized in that: the method comprises the following steps:

primary cooling treatment:

the liquid nitrogen supply is started, the fan rotates forwards, the second cold energy circulation loop is closed, the communication pipeline between the first exhaust port of the low-temperature treatment device of the first cold energy circulation loop and the first air inlet of the cold energy recovery device is opened, the communication pipeline between the second exhaust port of the cold energy recovery device and the second air inlet of the low-temperature treatment device is closed, and the branch pipeline communicated with the second exhaust port is opened;

when the temperature of the middle part of the cold storage material in the cold storage recovery device is lower than the preset temperature, a branch pipeline communicated with a second exhaust port is closed, the supply of liquid nitrogen is stopped, the fan is reversed, a second cold storage circulation loop is opened, and a first cold storage circulation loop is closed;

first cold circulation treatment:

when the temperature of the top of the cold storage material in the cold energy recovery device is higher than the temperature in the low-temperature treatment device, the fan rotates forwards, the first cold energy circulation loop is opened, and the second cold energy circulation loop is closed;

and (3) second cold circulation treatment:

when the temperature of the bottom of the cold storage material in the cold energy recovery device is higher than the temperature in the low-temperature treatment device, the fan rotates reversely, the first cold energy circulation loop is closed, and the second cold energy circulation loop is opened;

and the first cold circulation treatment and the second cold circulation treatment are alternately and circularly carried out in sequence.

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