JP2007024442A - Cooling method and cooling facility - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a new cooling method and a cooling facility capable of cooling sufficiently and efficiently by fundamentally reexamining behavior of operational cold air. <P>SOLUTION: This invention is the method to cool and store an object A to be stored by setting storage equipment 2 of the object A to be stored and a cold air supplier 3 in a building 11 and supplying operation cold air C from the cold air supplier 3 into the building 11. A duct 32 of the cold air supplier 3 has a take-in port 33 for recovering operated cold air C1 opened near a ceiling of the building 11 and has a discharge port 34 for supplying the operation cold air C which is obtained by re-cooling recovered operated cold air C1 opened near a floor surface in the building 11. In the building 11, in accordance with operation of the operated cold air C1 moving up, a circulating flow for sequentially feeding new cold air C from below is formed and the object A to be stored is always kept surrounded by the operation cold air C. <P>COPYRIGHT: (C)2007,JPO&INPIT

Description

  The present invention relates to a cooling method for freezing, refrigeration, and the like, and in particular, a novel cooling method for uniformly and efficiently cooling a large amount of objects stored in a warehouse building, and this method. This applies to the cooling facility to be applied.

  Conventionally, when cooling a warehouse building in a refrigerated warehouse, a refrigerated warehouse, etc., cool air is supplied from above the warehouse building, for example, near the ceiling, brought into contact with the storage object while being lowered, and after cooling this thing, The method of recovering in the downward direction and using it for circulation was used. This is presumably because the cold air is heavier than air having a higher temperature, moves naturally downward, and stays at the bottom. Certainly, this kind of cold air circulation is a natural movement in accordance with the laws of physics, but the actual cold air behavior is affected by the individual temperature conditions etc. The stored items could not be cooled uniformly.

  That is, the cold air usually descends so as to sew between a large amount of stored items stocked in the building, but the temperature of the stored items is not necessarily constant. For example, when newly stored items are brought in from the outside, the ambient temperature of the place is partially increased, so that the air (cold air) in the vicinity is pushed up (so-called updraft), and The pressure will also increase. Therefore, the naturally descending cold air tends to descend so as to avoid the place of the newly loaded storage object, in other words, a flow path with low movement resistance that has already been cooled. For this reason, in the cooling method that naturally cools down the air, there is a phenomenon in which the object to be stored that the cold air has avoided is not sufficiently cooled, and the desired quality cannot be maintained.

  However, in the past, it was captured by the unquestionable principle that cold air naturally falls, and it was considered technical common sense to cool the stored items by supplying cold air from the vicinity of the ceiling. Was never caught. Moreover, even if there is an object to be stored that is insufficiently cooled, it seems that the surface has been cooled, such as frost on the surface, at least during cargo handling operations. No further attention was paid to the fundamental improvements for further certainty.

  Also, in the conventional cooling method that naturally lowers the cold air, as described above, the cold air descends while avoiding the high heat load portion, so even if this cold air is collected and re-cooled, it is actually Is still cold, in other words, cold air still having cooling capacity is re-cooled, and therefore the cooling efficiency in the heat exchanger responsible for re-cooling is not good.

  The present invention has been made in view of such a background, and has fundamentally investigated the behavior of cold air that contributes to cooling, and based on that knowledge, a novel and effective cooling action can be expected. The development of a new cooling method and cooling facility.

  In other words, the cooling method according to claim 1 is provided with a storage facility for storage objects and a cold air supply device in the building, and the building is kept in a required low temperature atmosphere by the action cold air from the cold air supply device, and stored. In the method for cooling and preserving an object, the cold air supply device collects the collected cold air that has finished the action in the building from above and collects the action cold air that has been cooled again. It is formed so as to exhale from the lower part of the neighborhood, so that in the building, in accordance with the action of the working cold air that moves up and down, a circulating flow is formed in which new working cold air is sequentially embedded from the lower part, and the surroundings of the storage object are formed. It is characterized by being always surrounded by cold working air.

According to a second aspect of the present invention, there is provided a cooling facility in which a storage facility for storing objects and a cold air supply device are installed in the building, and the building has a low-temperature atmosphere required for the building by operating cold air from the cold air supply device. The cold supply device comprises a heat exchanger for recooling the operated cold air, a duct provided before and after the heat exchanger, and a blower fan provided in the duct. In addition, the duct is configured such that an intake port for collecting the operating cold air is opened near the ceiling in the building, and an outlet for supplying the operating cold air is opened near the floor in the building. Yes,
As a result, in the building, a circulation flow was introduced in which new working cold air was introduced sequentially from the bottom in accordance with the action of the working cold air that moved up and moved, so that the surroundings of the storage object were always surrounded by the working cold air. Is a feature.

Furthermore, in the cooling facility according to claim 3, in addition to the requirement according to claim 2, the heat exchanger is operated by a dual refrigeration cycle in which an ammonia cycle is formed on the high side and a carbon dioxide gas cycle is formed on the low side. It is what
In recooling the collected operating cold air with a heat exchanger, the carbon dioxide medium cooled with the ammonia medium in the cascade condenser is supplied to the heat exchanger that is the target evaporator so that the operating cold air is cooled. It is characterized by what has been done.

The above-described problems can be solved by using the configuration of the invention described in each of the claims.
That is, according to the first or second aspect of the invention, since the operating cold air is collected from above the building and new operating cold air is supplied from below such as near the floor of the building, As the cold air rises, new working cold air can be sequentially fed from below. For this reason, even in the building, even if there is a part to be stored (container) with a high heat load, the surroundings can always be surrounded by working cold air, and the stored object can be cooled uniformly and efficiently. .
Further, in the present invention, the operated cold air whose temperature has been somewhat raised after the operation is recovered and re-cooled, the cooling efficiency here is also good, and more efficient operation can be performed.

  Further, according to the invention described in claim 3, since the chilled air in the building is re-cooled by the dual refrigeration cycle to which the natural refrigerant (natural working medium) is applied, the operation is friendly to the environment and has good thermal efficiency. Can be done. In particular, in a carbon dioxide gas cycle, a cascade condenser is installed at a position higher than the heat exchanger, for example, on the roof of a building, so that a liquid head difference of a carbon dioxide medium is formed between them, and this is utilized. Since the carbon dioxide medium can be circulated naturally, more efficient operation can be performed.

  The best mode of the present invention is as described in the following examples. In the description, first, an example of the cooling facility 1 which is the facility of the present invention will be described, and then the cooling method of the storage object A by the cooling facility 1 will be described, and the cooling method which is the method of the present invention will also be described. explain.

  The cooling facility 1 is substantially constituted by a building 11 as shown in a skeletal cross-sectional view in the front sectional view of FIG. 1 as an example, and a storage facility 2 that cools (stores at low temperature) the storage object A therein. A cold air supply device 3 is provided for supplying cold air that bears a cooling action (hereinafter referred to as working cold air C) into the facility. The cooling facility 1 (building 11) is made of a material having a sufficient heat insulating effect on the outer wall or the like, and usually stores a large amount of articles A to be stored, so it is often a high-rise building. The cooling facility 1 can function as a refrigerator or a freezer mainly by the action (temperature setting) of the cold air supply device 3. Hereinafter, the storage facility 2 and the cold air supply device 3 will be further described.

First, the storage facility 2 will be described. This is a part for storing the article A to be stored in the building 11, and as a form thereof, a multistage rack 21 as shown in FIG. 1 is preferable. As an example, the rack 21 is configured by combining a mounting plate 23 with a column 22 to which an angle member is applied, and a container 24 that stores a storage object A is placed on the mounting plate 23 for storage. is there. Thereby, it becomes easy to carry in and carry out an arbitrary container 24 as needed. In order to efficiently take out (pick) such a container 24, it is preferable to dispose a crane 25 for cargo handling in the building 11.
In the present embodiment, the rack 21 is configured in a multi-stage shape and the container 24 is accommodated in the rack space. However, the rack 21 is configured depending on the type of the storage object A, the structure of the building 11, and the like. Instead, the container 24 may be directly stacked.

  Next, the cold air supply device 3 will be described. In this example, a heat exchanger 31 that directly takes a cooling action is provided in a duct 32 formed in a suspended (vertical) state along a side wall surface in the building 11 as an example. The duct 32 has an intake port 33 on the upper side and a discharge port 34 on the lower side. In addition, a blower fan 35 is provided in the vicinity of the heat exchanger 31, thereby circulating the working cold air C in the building 11. Specifically, cold air that has finished the cooling operation and rises in the building 11 (rack space) (hereinafter referred to as “acted cold air C1”) is taken in from above and collected, and the heat exchanger 31 in the duct 32 is recovered. Then, after re-cooling, the cold air C is discharged from below the building 11 (near the floor). Further, due to such a configuration, it is preferable to provide a louver 34 </ b> A for adjusting the wind direction and the air volume of the working cold air C at the discharge port 34.

In the present embodiment, the heat exchanger 31 and the blower fan 35 are provided near the floor surface in the duct 32 to improve convenience (maintenance) when replacing the blower fan 35, for example. The position where the exchanger 31 is provided is not necessarily limited to the vicinity of the floor surface. In particular, the blower fan 35 can be provided near the discharge port 34, or in consideration of effective circulation of the cold air (air) in the building 11, for example, at a plurality of locations as appropriate over the entire area of the duct 32. Even if it is provided, it does not matter.
The discharge port 34 can be provided at one location on the inside of the side wall surface when the building 11 is viewed from a plane, and a plurality of side wall surfaces are arranged so that the discharged working cold C spreads uniformly in the building 11. It is also possible to provide it inside. Furthermore, the discharge position may be extended near the floor surface along the peripheral wall surface.

Further, the cooling of the applied cold air C1 by the heat exchanger 31 is performed by operating a refrigeration system. Hereinafter, an example of this system will be described. For example, as shown in FIG. 2, the refrigeration system can employ a dual refrigeration cycle 4 in which an ammonia cycle 4A is combined on the high element side and a carbon dioxide gas cycle 4B is combined on the low element side. It is configured as an evaporator 46 (which will be described later) that performs desired cooling in the cycle 4B.
The ammonia cycle 4A includes, as an example, a compressor 41, a condenser 42, an expansion valve 43, and a cascade condenser 44. By the cascade condenser 44, the carbon dioxide medium in the carbon dioxide gas cycle 4B is substantially supplied. Cooling. On the other hand, the carbon dioxide gas cycle 4B includes a flow rate adjusting valve 45 and an evaporator 46 (heat exchanger 31) in addition to the cascade condenser 44 described above as an example.
The cascade condenser 44 is preferably installed at a position higher than the evaporator 46 (heat exchanger 31), for example, on the rooftop of the building 11, and a liquid head difference of the carbon dioxide medium is formed therebetween. This is because in the carbon dioxide gas cycle 4B, a carbon dioxide medium is naturally circulated by using this liquid head difference and an extremely efficient operation is performed without incorporating a compressor. In the figure, reference numeral 47 is a refrigerant pipe for flowing a carbon dioxide medium through the heat exchanger 31.

Here, the operation state of the above-described dual refrigeration cycle 4 will be described. First, in the ammonia cycle 4A, when the gaseous ammonia medium compressed by the compressor 41 passes through the condenser 42, it is cooled by cooling water or air to become a liquid. The ammonia medium that has become liquid is expanded to a saturation pressure corresponding to a necessary low temperature by the expansion valve 43 and then evaporated by the cascade condenser 44 to become a gas. At this time, the ammonia medium takes heat from the carbon dioxide medium in the carbon dioxide gas cycle 4B and liquefies it.
On the other hand, in the carbon dioxide cycle 4B, the liquefied carbon dioxide cooled and liquefied by the cascade condenser 44 naturally descends due to the liquid head difference formed between the two members, passes through the flow rate adjustment valve 45, and reaches the target cooling. Enter the evaporator 46 (heat exchanger 31). Here, the liquefied carbon dioxide gas is warmed and evaporated, and at this time, heat is taken from the surroundings to cool the worked cold air C1. In addition, the carbon dioxide medium that has cooled the operated cold air C <b> 1 returns to the cascade condenser 44 again as a gas.
Reference numeral 48 in the figure denotes a load sensor provided in the building 11. Specifically, a temperature sensor or the like installed near the ceiling is applied, and the operation status of the dual refrigeration cycle 4 is determined depending on the temperature status. It is corrected as appropriate so that an optimal cooling environment can be obtained.

The facility of the present invention (cooling facility 1) has the basic structure described above, and the method of the present invention (cooling method) will be described below while describing the cooling mode of the cooling facility 1.
First, when the dual refrigeration cycle 4 is operated, for example, a carbon dioxide medium in the refrigerant pipe 47 cooled by the cascade condenser 44 is liquefied and reaches the heat exchanger 31 (evaporator 46). On the other hand, in the cooling facility 1, the cool air in the building 11 is circulated by driving the blower fan 35.
Specifically, for example, as shown in FIG. 3 (a), when a newly stored object A (container 24) is newly brought into the building 11, the working cold air C in the vicinity thereof is covered. While cooling the stored item A, the temperature of the stored item A rises to some extent and becomes the cold air C1 that has been actuated, and the rack space is raised. In this way, the operated cold air C <b> 1 reaching the upper side in the building 11 is recovered from the intake port 33 by the action of the blower fan 35 activated in the duct 32 and descends in the duct 32.

  At that time, the applied cold air C1 is cooled while passing through the heat exchanger 31 (for example, a cooling fin), and is supplied into the building 11 (rack space) from the discharge port 34 near the floor of the building 11. . Since the operating cold air C1 recovered in the duct 32 is in a state in which the temperature has risen somewhat as described above, recooling the air by the heat exchanger 31 is effective for cooling efficiency in the heat exchanger 31. It can be said that it is preferable also from a point. Needless to say, such defrosting device or the like is appropriately provided in the duct 32 when defrosting or the like is effective in association with the recooling of the collected cold air C1.

  On the other hand, as shown in FIG. 3 (a), the working cold C supplied from the discharge port 34 to the rack space is viewed from below so as to embed the moving space in accordance with the rise of the working cold C1. Get in. The operation (circulation) of the cold air proceeds simultaneously as if the new working cold air C is pulled by the rise of the working cold air C1. For this reason, even if there is a newly stored article A having a high heat load in the building 11 as shown in FIG. 3B, the surrounding area and the entire inside of the building 11 always act as shown in FIG. It is filled with cold air C. Therefore, as compared with the conventional cooling method in which the cool air is simply lowered from above, the working cool air C does not avoid a place where the heat load is high, and the storage object A can be cooled uniformly and reliably.

It is front sectional drawing which shows an example of the cooling facility of this invention skeletally. It is explanatory drawing which shows an example of the 2nd freezing cycle which makes the heat exchanger of a cold air supply apparatus act as an evaporator (cooler). It is front sectional drawing which shows the mode of the circulation of the cool air in a building in steps.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Cooling facility 2 Storage equipment 3 Cold air supply device 4 Dual refrigeration cycle 4A Ammonia cycle 4B Carbon dioxide gas cycle 11 Building 21 Rack 22 Pillar 23 Mounting plate 24 Container 25 Crane 31 Heat exchanger 32 Duct 33 Inlet 34 Outlet 34A Louver 35 Blower fan 41 Compressor 42 Condenser 43 Expansion valve 44 Cascade capacitor 45 Flow rate adjusting valve 46 Evaporator 47 Refrigerant piping 48 Load sensor A Storage object C Working cold C1 Working cold

Claims (3)

In the method of installing the storage equipment and cold air supply device of the storage object in the building, keeping the building in the required low temperature atmosphere by the action cold air from the cold air supply device, and cooling and storing the storage object,
The cold air supply device takes in and collects the cold air that has finished working in the building from above and collects the cold air that has been cooled again, so that it is discharged from below the floor in the building. And
In this way, in the building, in accordance with the action of the working cold air that moves up and down, a circulating flow that embeds new working cold air sequentially from below is formed, and the surroundings of the storage object are always surrounded by the working cold air. A cooling method characterized. In facilities that store storage objects and cool air supply devices in the buildings, and cool and store the stored items as a low-temperature atmosphere required by the building cold air by the cold air supply devices,
The cold air supply device comprises a heat exchanger for recooling the action cold air, a duct provided before and after the heat exchanger, and a blower fan provided in the duct,
In addition, the duct has an intake port for collecting the action cold air being opened near the ceiling in the building, and a discharge port for supplying the action cold air is being opened near the floor in the building,
As a result, in the building, a circulation flow was introduced in which new working cold air was introduced sequentially from the bottom in accordance with the action of the working cold air that moved up and moved, so that the surroundings of the storage object were always surrounded by the working cold air. A cooling facility characterized by The heat exchanger is operated by a dual refrigeration cycle in which the high-end side is constituted by an ammonia cycle and the low-end side is constituted by a carbon dioxide gas cycle.
In recooling the collected operating cold air with a heat exchanger, the carbon dioxide medium cooled with the ammonia medium in the cascade condenser is supplied to the heat exchanger that is the target evaporator so that the operating cold air is cooled. The cooling facility according to claim 2, wherein

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