JP3292408B2 - Membrane ice manufacturing device and ice heat storage system using the device - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a film type ice manufacturing apparatus for manufacturing ice without using a chlorofluorocarbon-based refrigerant and an ice heat storage system using the apparatus.

[0002]

2. Description of the Related Art In recent years, the maximum power consumption in summer has increased due to a rapid increase in power used for cooling and the like. On the other hand, as typified by energy saving in a power consuming industry, the industrial industry is trying to reduce the dependence on electric energy, and accordingly, the annual average load factor for power generation equipment tends to decrease. For this reason, technology for efficiently storing nighttime power energy and utilizing it for cooling or the like has become extremely useful, and practical use of an ice heat storage system has been attempted. In addition, conventional ice heat storage devices using a chlorofluorocarbon-based refrigerant are not preferable from the viewpoint of protection of the ozone layer. Therefore, an ice production device capable of producing ice without using a chlorofluorocarbon-based refrigerant and an ice using the same. Heat storage systems are receiving attention.

The applicant of the present invention has previously proposed an ice heat storage system of this type described in Japanese Patent Application Laid-Open No. 3-912623. In this device, a heat storage body that can have a large water-steam interface area is formed using a water-absorbing polymer gel, and the inside of an ice heat storage tank provided with a plurality of the heat storage bodies is evacuated by a vacuum exhaust device. In addition, a large amount of water in the gel is efficiently frozen with the release of latent heat of evaporation. In this case, since the ice heat storage tank can be kept in a decompressed state, there is an advantage that the energy loss of evacuation for exhaust can be reduced and the operation efficiency can be improved.

[0004]

However, even in such an ice making apparatus and an ice heat storage system, since ice is generated in a heat storage body using a water-absorbing polymer gel,
In order to increase the amount of ice heat storage while obtaining a predetermined heat exchange efficiency, it is necessary to increase the number of the heat storage bodies, and it is necessary to arrange many heat storage bodies in the ice heat storage tank at predetermined intervals. . In addition, since a gap for exhaust is provided between a large number of heat storage bodies, there remains a problem to be solved in terms of reduction of ice heat storage space.

Accordingly, the present invention realizes an ice producing apparatus capable of separating the produced ice and performing continuous ice production, and performing efficient cold heat storage by the separated ice to reduce the space of the heat storage tank. It is an object of the present invention to provide an ice heat storage system that achieves reduction.

[0006]

In order to achieve the above object, a membrane ice manufacturing apparatus according to the first aspect of the present invention has a hydrophobic membrane or plate having a large number of micropores and one side of which is in contact with water. And a gas chamber formed at least in part by the other surface of the hydrophobic film or plate, and an exhaust unit that exhausts water vapor while depressurizing the gas chamber. Ice is generated on one surface side of the hydrophobic film or plate.

Further, the invention according to claim 2 is characterized in that the gas phase chamber is arranged below a surface of water that contacts one surface side of the hydrophobic membrane or plate, The invention according to claim 3 is characterized in that ice adhered to the hydrophobic film or plate is separated from the film or plate by increasing the pressure in the gas phase chamber from a reduced pressure state.

[0008] Further, the invention according to claim 4 is based on claim 1,
4. An ice heat storage system using the film-type ice manufacturing device according to 2 or 3, wherein an ice making tank containing water that contacts one surface of the hydrophobic film or plate, and one surface of the hydrophobic film or plate. Ice storage means for storing the ice generated on the side and storing the cold heat, and transport means for transporting the ice generated on one side of the hydrophobic film or plate into the ice storage tank. It is assumed that.

[0009]

According to the first aspect of the present invention, since the other surface of the hydrophobic film or plate having a large number of micropores and contacting water on one surface forms at least a part of the gas phase chamber, When the vapor pressure chamber is decompressed and the water vapor is exhausted by the evacuation means, heat is taken from one side of the hydrophobic film or plate as the water vapor evaporates to the side of the vapor phase chamber, and the water contacting this one side is removed. Ice forms on the surface. Therefore, if ice is separated from the other side of the hydrophobic membrane or plate, continuous production of ice becomes possible.

According to the second aspect of the present invention, the gas phase chamber is disposed below the surface of the water in contact with one surface of the hydrophobic membrane or plate. Therefore, ice generated on one surface side of the hydrophobic film or plate can be floated by buoyancy, and ice separation and collection can be facilitated. According to the third aspect of the present invention, since the film or plate is hydrophobic, if the pressure in the gas phase chamber is increased from a reduced pressure, ice adhered to the film or plate can be easily separated.

According to the fourth aspect of the present invention, in a state where one surface of the hydrophobic film or plate is in contact with water in the ice making tank, ice is generated on one surface of the film or plate, and the ice is produced by the conveying means. Separated from the film or plate, and transferred to and stored in the ice heat storage means, cold heat storage by ice is performed. Therefore, efficient cold heat storage by the separated ice becomes possible.

[0012]

DESCRIPTION OF THE PREFERRED EMBODIMENTS Embodiments of the present invention will be specifically described below with reference to the drawings. <Embodiment of Membrane Ice Manufacturing Apparatus> FIGS. 1 and 2 show an embodiment of a membrane ice manufacturing apparatus according to the first to third aspects of the present invention.

First, the configuration will be described. In FIGS. 1 and 2, reference numeral 11 denotes a hydrophobic porous membrane composed of a precision membrane capable of separating water vapor from water, a so-called membrane-evaporable precision membrane, an ultrafiltration membrane, and the like. It has a number of micropores (not shown) of several μm or less (for example, 2 μm or less). This hydrophobic porous membrane 11
The interior of the container 12 is divided into a liquid phase chamber 13 on the upper side in the figure and a gas phase chamber 14 on the lower side in the figure, and the liquid phase chamber 13 has a predetermined amount of water 21 (for example, distilled water). It is kept at atmospheric pressure by opening the upper part in the state of storing. Gas phase chamber 14 is a container
A predetermined pressure (for example, 4.5 mmHg) is applied by a vacuum pump (exhaust means) (not shown) connected to an exhaust pipe portion 12a below
(Or lower pressure), and a plastic dish 15 facing the lower surface of the hydrophobic porous membrane 11 is provided in the gas phase chamber 14. When the inside of the gas phase chamber 14 is depressurized, the perforated plate 15 supports the hydrophobic porous membrane 11 at a fixed position, and easily allows water vapor generated from the lower surface of the hydrophobic porous membrane 11 to pass therethrough. For this purpose, for example, a hydrophobic porous membrane 11 is stretched on
It is fixed to the lower end of 12b.

That is, in the present embodiment, a hydrophobic porous membrane 11 (hydrophobic membrane) having a large number of micropores and contacting water 21 on one side, and at least a part of the other side of the hydrophobic porous membrane 11 And a vacuum pump for depressurizing the inside of the gas phase chamber 14 and evacuating water vapor, and depressurizing and evacuating the inside of the gas phase chamber 14 by operating the vacuum pump. As a result, the water 21 is evaporated through the hydrophobic porous membrane 11, and ice 22 is generated on the upper surface side of the hydrophobic porous membrane 11 with the release of latent heat of evaporation (details will be described later).

In FIG. 1, reference numeral 16 denotes a pressure gauge mounted on the exhaust pipe portion 12a of the container 12, reference numeral 17 denotes a pressure adjusting valve capable of adjusting the pressure in the gas phase chamber 14, and reference numerals 18A, 18B, and 18C denote water, respectively. twenty one
A thermocouple (temperature detecting means) provided near the liquid surface position, the upper surface position of the hydrophobic porous film 11, or the lower surface position of the hydrophobic porous film 11. Here, the pressure regulating valve 17 is opened to open the gas phase chamber.
A valve capable of increasing the pressure inside the pressure-reduced state from a reduced pressure state.
Is a separating means for separating the ice 22 from the water 21 by a buoyancy difference from the water 21.

Next, the operation will be described. First, a predetermined amount of water 21 is stored in the container 12 in advance, and then the inside of the gas phase chamber 14 is depressurized by the vacuum pump and the exhaust amount is adjusted. The pressure gauge 17 indicates a pressure value of 4.5 mmHg. To do. At this time, the vapor pressure of the water 21 in the liquid phase chamber 13 is
When the pressure in 14 becomes considerably low, water 21 that does not pass through hydrophobic porous membrane 11 as liquid passes through hydrophobic porous membrane 11 as water vapor and evaporates toward gas phase chamber 14. Then, the water vapor is continuously exhausted by the vacuum pump while diffusing into the gas phase chamber 14 through the perforated plate 15.

In this exhaust state, the hydrophobic porous membrane 11
The latent heat of evaporation is released by the evaporation of the water 21 passing through, and the temperature of the water 21 contacting the hydrophobic porous membrane 11 and the upper surface thereof decreases, and the water vapor pressure in the gas phase chamber 14 also decreases with the temperature decrease. I do. Further, since the vapor pressure of water at 0 ° C. is 4.5 mmHg, the temperature of the water 21 drops to the freezing point, and ice 22 is generated. Since the ice 22 gradually increases in thickness and the pressure loss of the exhaust gas increases, it is necessary to separate the ice 22 from the hydrophobic porous membrane 11, but since the porous membrane 11 is hydrophobic, the pressure regulating valve 17 is opened to open the gas phase chamber. By temporarily returning the pressure inside 14 to the normal pressure side, ice 22
Can be easily separated from the hydrophobic porous membrane 11.
Therefore, when the evacuation is temporarily stopped after a predetermined time has elapsed and the pressure in the gas phase chamber 14 is reduced to the normal pressure side, the ice 22
Is separated from the hydrophobic porous membrane 11 and floats to the water surface side. Therefore, by repeatedly evacuating the gas phase chamber 14 while separating the hydrophobic porous membrane 11 and the ice 22, the ice 22 can be continuously produced.

FIG. 2 is a graph showing the results obtained by confirming the changes in the temperature on the liquid layer chamber 13 side and the pressure in the gas phase chamber 14 by performing experiments as described above. In this graph, the temperature B [° C.] is the temperature near the upper surface of the hydrophobic porous membrane 11 detected by the thermocouple 18B, and the temperature A [° C.] is the temperature near the water surface of the gas phase chamber 14 detected by the thermocouple 18A. , Pressure [mmHg] is the pressure in the gas phase chamber 14 indicated by the pressure gauge 16, and time [min] is the elapsed time from the start of the evacuation work.

In this experiment, a hydrophobic porous membrane 11 having an average pore diameter of 0.5 μm and a diameter of 80 mm was used, and 110 g of distilled water was used as water 21 at room temperature and an environment of 22 ° C.
The pump was evacuated for 0 minutes, and the amount of ice 22 generated was 3
7 g, the amount of water vapor evaporation through the hydrophobic porous membrane 11 is 12.5
It was 5 g. As shown in this graph, as the temperature of the water 21 in the liquid phase chamber 13 decreases with the evacuation by the vacuum pump, the pressure in the gas phase chamber 14 decreases, and the supercooling is eliminated through the supercooling section. Almost at the same time, the surface of the hydrophobic porous membrane 11 reaches the freezing point. As a result, the temperature and the pressure slightly increase, but ice 22 is generated on the upper surface side of the hydrophobic porous membrane 11, and the pressure decreases as the thickness increases. The portions indicated by arrows in the figure indicate changes in temperature and pressure when the evacuation is temporarily stopped and the ice 22 is separated from the hydrophobic porous membrane 11.

As described above, in this embodiment, since the other surface of the hydrophobic porous film 11 having a large number of micropores and having one surface in contact with the water 21 forms a part of the gas phase chamber 14, When the inside of the gas phase chamber 14 is depressurized and water vapor is evacuated by evacuation means such as a vacuum pump, heat is taken from one surface side of the hydrophobic porous membrane 11 with evaporation of the water vapor to the gas phase chamber 14 side. Ice 22 is formed in the water 21 contacting the one surface side. Therefore, when the ice 22 is separated from the other side of the hydrophobic porous membrane 11, an ice manufacturing apparatus capable of continuously manufacturing ice can be realized. Further, the gas phase chamber 14 is disposed below the surface of the water 21 in the liquid phase chamber 13, and the pressure inside the gas phase
In order to separate 22 from the porous membrane 11, the ice 22 generated on one side of the hydrophobic porous membrane 11 can be easily separated and floated to the water surface side by buoyancy.
Separation and collection can be facilitated.

The efficiency of ice formation in this embodiment is as follows.
It depends on the compression efficiency of the vacuum pump or vacuum compressor used for exhaustion, the membrane resistance of the hydrophobic porous membrane 11, the membrane surface temperature, and the condensation temperature of the water vapor to be exhausted. Is 0 ° C., the energy efficiency COP can be expected to be 5 to 6. <Embodiment of Ice Thermal Storage System> FIG. 3 is a diagram showing an embodiment of an ice thermal storage system according to the fourth aspect of the present invention.

As shown in FIG. 1, this ice heat storage system includes a membrane ice manufacturing apparatus 30 according to another embodiment of the present invention, Water in contact with the plurality of gas-phase chamber containers 34 and their outer surfaces (one surface)
An ice-making tank 51 accommodating 41, and a film-type ice making device in the ice-making tank 51
Ice storage tank that stores ice 42 produced by 30 and stores cold energy
A conveyer-shaped ice transfer unit 53 (conveying means) for conveying the ice 42 generated on the outer surface side of the gas phase chamber container 34 and floating on the water surface side in the ice making tank 51 into the ice heat storage tank 52; The ice 42 generated on the outer surface side of the gas-phase chamber 34 in the ice-making tank 51 is separated from the gas-phase chamber 34 in the ice-making tank 51 by temporarily releasing the reduced pressure in the gas-phase chamber of the film-type ice making apparatus 30 every ice-making time. And an automatic release valve 54 (separating means). In addition, this ice heat storage system produces ice using nighttime electric power and performs ice heat storage, and the stored cold energy is consumed by the air conditioner 60 in the daytime or the like.

More specifically, the membrane-type ice manufacturing apparatus 30 includes a plurality of substantially drum-shaped or substantially box-shaped gas-phase chamber containers 34, at least a pair of opposed flat surfaces of which are formed of a hydrophobic porous membrane (for details, see FIG. (Not shown, a hydrophobic porous plate may be used), and the hydrophobic porous membrane is the hydrophobic porous membrane 11 of the above-described example.
It is made of the same material as. The plurality of gas phase chamber containers 34 having the hydrophobic porous membrane are connected to a vacuum pump 36 via an exhaust pipe 35, and the gas phase chamber in the gas phase chamber container 34 is depressurized by the vacuum pump 36. And exhausted. That is, the gas phase chamber container 34, the pipe 35, and the vacuum pump 36 constitute the membrane ice manufacturing apparatus 30. The water 41 stored in the ice making tank 51 is appropriately replenished according to the ice making time by pumping water collected in a lower part of the ice heat storage tank 52 by an ice making pump 55. On the other hand, the cold water 41 accumulated in the lower part of the ice heat storage tank 52
Is supplied to an air conditioner 60 through a chilled water circulation pump 61 and consumes cold heat for air conditioning.
Sprinkled on ice 42 stored above 52. It is preferable to add an ice nucleus substance (for example, an ice nucleus active bacterium) to the water 41 in the ice making tank 51 and the ice heat storage tank 52 in order to suppress supercooling as much as possible.

As described above, in this embodiment, the water in the ice making tank 51 is
Ice is applied to the outer surface of the hydrophobic porous membrane of the gas phase chamber
42 is generated, and the operation of the automatic release valve 54
By temporarily increasing the internal pressure from the reduced pressure, the ice
42 is separated from the hydrophobic porous membrane, and ice 42 that floats on the water surface side is transported to the ice thermal storage tank 52 by the transport unit 53, so that ice heat storage that performs night-time continuous ice production using night power is used. Done. Therefore, efficient cold heat storage by the ice 42 separated from the film ice manufacturing apparatus 30 in the ice making tank 51 becomes possible, whereby the space of the ice heat storage tank 52 with respect to the heat storage capacity can be reduced, and the space can be saved. Can be achieved.

In each of the above-described embodiments, the separation means has been described as an example in which the pressure in the gas phase chamber is temporarily increased from the reduced pressure for ice making and separated by buoyancy. The vibration may be a vibration (eg, ultrasonic vibration), a sound vibration, an external force, or a mechanical peeling action. Further, instead of the hydrophobic porous membrane, a porous plate having a large number of fine pores having a pore diameter of several μm or less can be used.

[0026]

According to the first aspect of the present invention, the evacuation means reduces the pressure in the gas phase chamber and exhausts the water vapor, and the one side of the hydrophobic film or plate with the evaporation of the water vapor to the gas phase chamber side. Heat is taken from the side and ice is generated in the water in contact with the one side, so that ice can be continuously produced by separating ice from the other side of the hydrophobic membrane or plate. A small-sized film-type ice manufacturing device can be provided.

According to the second aspect of the present invention, since the gas phase chamber is disposed below the surface of the water in contact with one surface of the hydrophobic film or plate, one surface of the hydrophobic film or plate is disposed. The ice generated in the above can be floated by buoyancy, and the separation and collection of the ice can be facilitated. According to the third aspect of the present invention, since a hydrophobic film or plate is used, and the pressure in the gas phase chamber is increased from a reduced pressure to separate ice adhered to the film or plate, the separation operation is easily performed. be able to.

According to the fourth aspect of the present invention, ice is generated on one side of the membrane or plate while the one side of the hydrophobic film or plate is in contact with the water in the ice making tank, and the ice is generated. Since the ice is separated from the ice making unit by the transfer means and stored in the ice heat storage means, it is possible to perform efficient cold heat storage by using ice separated from the ice making unit, and to provide an ice heat storage system that reduces the space required for the heat storage tank. be able to.

[Brief description of the drawings]

FIG. 1 is a front sectional view showing an embodiment of a membrane type ice manufacturing apparatus according to the present invention.

FIG. 2 is a graph showing a temperature change on a liquid phase chamber side and a pressure change on a gas phase chamber side during an evacuation operation of one embodiment.

FIG. 3 is a configuration diagram showing an embodiment of an ice heat storage system according to the present invention.

[Explanation of symbols]

 11 Hydrophobic porous membrane (hydrophobic membrane) 13 Liquid phase chamber 14 Gas phase chamber 17 Pressure regulating valve (separation means) 21 Distilled water 22 Ice 30 Membrane ice manufacturing equipment 34 Gas phase chamber container (hydrophobic membrane) 41 Water 42 Ice 51 Ice making tank 52 Ice storage tank 53 Ice transfer unit (transportation means) 54 Automatic release valve (separation means) 60 Air conditioner

──────────────────────────────────────────────────続 き Continuation of the front page (72) Inventor Satoshi Hongo 1-35-8 Nihonbashi Kakigami-cho, Chuo-ku, Tokyo Sanken Equipment Co., Ltd. (56) References JP-A-6-207726 (JP, A JP-A-6-74497 (JP, A) JP-A-6-241628 (JP, A) JP-A-4-350483 (JP, A) JP-A-63-243665 (JP, A) JP-A-60-1984 34785 (JP, A) (58) Field surveyed (Int. Cl. ⁷ , DB name) F25C 1/00-1/12 F25C 1/16-5/18 F24F 5/00 102

Claims (4)

(57) [Claims] 1. A hydrophobic film or plate having a large number of micropores and contacting water on one side, a gas phase chamber at least partially formed by the other surface of the hydrophobic film or plate, Exhaust means for depressurizing the gas phase chamber and exhausting water vapor, wherein ice is generated on one surface side of the hydrophobic film or plate by operation of the exhaust means. . 2. A film-type ice manufacturing apparatus according to claim 1, wherein said gas-phase chamber is disposed below a surface of water in contact with one surface of said hydrophobic film or plate. 3. A method according to claim 1, further comprising the step of increasing pressure in said gas phase chamber from a reduced pressure state to separate ice adhered to said hydrophobic film or plate from said film or plate. 3. The membrane ice manufacturing apparatus according to 2. 4. An ice heat storage system using the film-type ice manufacturing apparatus according to claim 1, 2, or 3, wherein: an ice-making tank for storing water in contact with one surface side of the hydrophobic film or plate; Ice storage means for storing ice generated on one surface side of the hydrophobic film or plate and storing the cold heat, and transporting the ice generated on one surface side of the hydrophobic film or plate into an ice storage tank Means, and an ice heat storage system comprising: