JP2012163312A - Nitrogen ice making device and method, and cooling apparatus - Google Patents

Abstract

PROBLEM TO BE SOLVED: To efficiently make a large amount of ice/nitrogen ice by freezing nitrogen water (water obtained by replacing dissolved oxygen in water with nitrogen gas).SOLUTION: This nitrogen ice making device for producing nitrogen ice which is ice obtained by freezing the water prepared by replacing the dissolved oxygen in water with the nitrogen gas, includes: a water tank (30) having airtightness for blocking intrusion of a gas from ambient air; a nitrogen gas injector (28) for injecting the nitrogen gas to the water passing therethrough; a nitrogen gas extractor (14) for extracting the nitrogen gas from the air and supplying the extracted nitrogen gas to the nitrogen gas injector (28); water circulating means (31, 20, 32, 22) for taking out the water from the water tank (30) and circulating the water so that the water passes through the nitrogen gas injector (28) and then returns to the water tank (30) to obtain the water replaced with the nitrogen gas from the water in the water tank (30); and an ice making machine (40) for making the nitrogen ice by freezing the nitrogen gas-replacement water taken out from the water tank (30).

Description

  The present invention relates to ice frozen in nitrogen water (water in which dissolved oxygen in water is replaced with nitrogen gas), and an apparatus and method for producing nitrogen ice.

Patent Document 1 discloses a sherbet ice production system as a plant on land.
Patent Document 2 discloses a nitrogen gas sealed ice manufacturing apparatus.

JP 2010-169322 A JP 2007-155172 A

The nitrogen gas-sealed ice production apparatus of Patent Document 2 is an invention that is particularly useful for producing nitrogen ice in a fishing boat and maintaining the freshness of the fish. In the case of producing nitrogen ice on land equipment, it is necessary to configure an appropriate equipment in consideration of the fact that there may be a distance between the production place and the use place and time.
The problem to be solved by the present invention is to provide a configuration suitable for producing nitrogen ice on land.

In order to solve the above problems, a nitrogen ice production apparatus of the present invention has the following configuration. The numbers in parentheses are reference numerals in the drawings described later, and are attached for reference.
A first aspect of the present invention is a nitrogen ice production apparatus for producing nitrogen ice, which is ice obtained by freezing water obtained by substituting dissolved oxygen in water with nitrogen gas, and prevents intrusion of gas from the surrounding atmosphere. An airtight water tank (30) for blocking, a nitrogen gas injector (28) for injecting nitrogen gas into the passing water, and extracting nitrogen gas from the atmosphere, and extracting the extracted nitrogen gas into the nitrogen gas Nitrogen gas extractor (14) to be supplied to the injector (28), and water in the water tank (30) to be replaced by nitrogen gas, water is taken out from the water tank (30), Water circulation means (31, 20, 32, 22) for circulating water so as to pass through the nitrogen gas injector (28) and return to the water tank (30), and nitrogen extracted from the water tank (30) And an ice making machine (40) for producing nitrogen ice by freezing the gas-substituted water.

Furthermore, in the nitrogen ice production apparatus, it is preferable that a cooling device for cooling the water in the water tank (30) is provided.
Further, in the above-mentioned nitrogen ice production apparatus, it is preferable that the ice making machine (40) includes means for feeding nitrogen gas, and in the ice making process in the ice making machine (40), it is preferable to perform ice making while feeding nitrogen gas. It is.
Furthermore, in the nitrogen ice production apparatus, the water tank (30) is composed of two tanks having the same function, and water can be circulated between each tank and the nitrogen gas injector (28), and It is preferable that nitrogen ice-substituted water can be taken out from each tank and nitrogen ice can be produced by the ice making machine (40).

  Furthermore, in the above-mentioned nitrogen ice production apparatus, an ice breaker (50) for breaking the nitrogen ice produced by the ice making machine (40), an ice storage chamber (60) for storing nitrogen ice, and a nitrogen ice stored in the ice storage chamber A scraping and leveling device, a measuring device (70) for measuring nitrogen ice scraped by the scraping device, and a shipping device (80) for shipping the nitrogen ice measured by the measuring device. It is preferable to have

A second aspect of the present invention is a cooling device that is a commercial or household freezer, refrigerator, or refrigerator-freezer, wherein any one of the above-described nitrogen ice production apparatuses is incorporated as an ice making apparatus.
Furthermore, in the cooling device, one or more of a freezing room, an ice storage room, a refrigerated room, a chilled room, and a vegetable room, a decompression unit that evacuates each of the one or more rooms, and the 1 or Nitrogen gas supply means for feeding nitrogen gas to each of the plurality of chambers, and after the pressure is reduced by the pressure reducing means when each of the one or the plurality of chambers is sealed, the nitrogen gas is supplied by the nitrogen gas supply means Thus, the atmosphere in the one or more rooms is replaced with nitrogen.

  A third aspect of the present invention is an airtight water tank that blocks intrusion of gas from the surrounding atmosphere in order to produce nitrogen ice, which is ice obtained by freezing water in which dissolved oxygen in water is replaced with nitrogen gas (30), a nitrogen gas injector (28) for injecting nitrogen gas into the passing water, and extracting nitrogen gas from the atmosphere, and extracting the extracted nitrogen gas to the nitrogen gas injector (28) Nitrogen gas extractor to supply (14) and water in the water tank (30) to replace the nitrogen gas, water is taken out from the water tank (30), the nitrogen gas injector (28) Water circulation means (31, 20, 32, 22) for circulating water so as to return to the water tank (30), and the nitrogen gas-substituted water taken out from the water tank (30) is frozen. An ice making machine (40) for producing nitrogen ice, and a method for producing nitrogen ice using a nitrogen ice production device comprising: A step of producing water in which dissolved oxygen is replaced with nitrogen gas by circulating water through the nitrogen gas injector and returning to the water tank by the water circulation means, and the water in which the nitrogen gas is replaced, And a step of producing nitrogen ice by freezing with the ice making machine.

The operation method (action) in one embodiment of this nitrogen ice production apparatus is outlined as follows.
First, put water (tap water, groundwater, seawater, artificial seasoned water, artificial seawater, etc.) into the water tank to a state that is almost full. Next, the circulation pump is operated to circulate the water in the water tank back to the original water tank through the nitrogen gas injector. Then, the air compressor is operated to feed the ambient air into the nitrogen gas extractor. Then, the nitrogen gas extractor releases oxygen from the side port, and dissolves a gas rich in nitrogen gas into the circulating water through the injection nozzle of the nitrogen gas injector. Since the water in the water tank is circulated by a circulation pump and nitrogen gas is dissolved when passing through the nitrogen gas injector, the water in the water tank gradually becomes water in which a lot of nitrogen gas is dissolved. Since nitrogen gas dissolves in the water, the oxygen previously dissolved in the water is expelled and accumulates in the space above the water tank. Oxygen accumulated in the upper part of the tank is released from the gas discharge port. This gas discharge port has a structure that does not allow entry from the outside, and oxygen in the atmosphere does not dissolve in water in the tank. If the operation is continued for about 10 hours, 20 tons of water can be converted into 99% nitrogen-dissolved water.
Thus, the water in the water tank becomes water containing a lot of nitrogen. The water in the water tank is cooled as necessary. For example, it is cooled to about 5 degrees Celsius. It is known that water dissolves more gas at lower temperatures. A thermometer and a dissolved oxygen meter are attached to the water tank, and it is possible to know how much nitrogen water in the water tank is nitrogen-containing water by reading the guidelines of these meters.
Next, water containing a large amount of nitrogen is conveyed to an ice making machine to produce nitrogen ice. It is desirable to use an ice making machine that instantly freezes water. For example, a vertical metal plate with both a cooling device and a heater is used. Nitrogen water is dropped from above with the metal plate cooled to minus 25 degrees. Adjust the speed at which the water is dripped so that it will freeze until the water drops down. If this operation is continued for about 20 minutes, a plate-like ice with an appropriate thickness can be formed. Therefore, stop dripping nitrogen water and stop cooling the metal plate. On the contrary, when the heater is operated, the plate-shaped ice peels off from the metal plate and falls. Nitrogen ice crushed by the impact of falling is further transported to the icebreaker by a belt conveyor, and further crushed to an appropriate size. Bring the crushed nitrogen ice to the ice storage room.
In the ice storage room, moderately sized ice is stored like a mountain in the atmosphere, and temperature control appropriate for storing ice is performed. Ice piled up in a mountain shape is leveled by a rake-shaped rake. The nitrogen ice scraped off by the rake is weighed by a measuring instrument and shipped by a shipping device. At the time of shipment to the truck bed, the measured nitrogen ice is carried directly to the truck bed. In the case of shipment in a bag, for example, the bag is packed in a 20 kg bag and shipped.

Since one aspect of the nitrogen ice production apparatus of the present invention has such a configuration and operates as described above, ice containing a large amount of nitrogen can be produced in a large amount in a short time.
Nitrogen ice does not contain oxygen, so it is useful for preventing oxidation and maintaining freshness.
By storing the water tank, the ice making machine, and the ice storage chamber in a single casing, a nitrogen ice production apparatus for use in stores and homes can be configured.
During ice production, ice containing a large amount of nitrogen is rapidly cooled and produced in a short time, but it is known that it will stick afterwards because the work is performed in the atmosphere during storage and storage. It is done. However, compared to normal ice (ice frozen from water that does not contain nitrogen), it is easier to handle the portion that stuck afterwards, compared to the case where nitrogen ice is difficult to separate. This is one of the characteristics of nitrogen ice. The part that freezes afterwards (external) is thought to be because the crystal structure of ice contains oxygen and is different from the crystal structure containing nitrogen inside.

FIG. 1 is a diagram showing an overall configuration of a nitrogen ice production apparatus.

Hereinafter, embodiments of the present invention will be described with reference to the drawings.
FIG. 1 is a diagram showing an overall configuration of a nitrogen ice production apparatus. The air compressor 10 is an air compressor that compresses the atmosphere and sends the compressed air to the nitrogen gas extractor 14 via the compressed air feed pipe 11. For example, an oil-free babycon (registered trademark) of Hitachi Industrial Equipment Systems Co., Ltd. can be used. Use a supply air pressure of 0.5 to 0.9 megapascals.

  The nitrogen gas extractor 14 takes compressed air into one end of a pressure vessel provided with a nitrogen separation membrane made of a polyimide hollow fiber membrane, purges (discharges) oxygen from a side port, and takes out nitrogen gas from multiple ends of the pressure vessel. Is. This utilizes the fact that the permeation rate of the membrane varies depending on the type of gas. For example, a deaeration device “Riprel” (registered trademark) manufactured by Katayama Chemical Industry Research Institute Co., Ltd. in Higashiyodogawa-ku, Osaka can be used. . This deaeration device is provided as a device in which a nitrogen gas extractor 14, a nitrogen gas feed pipe 15, and a nitrogen gas injector 28 are integrally formed. The nitrogen gas feed pipe 15 is a pipe having a structure capable of withstanding the pressure of 0.8 megapascal nitrogen gas.

  The nitrogen gas injector 28 is treated by passing 2 tonnes (2 cubic meters) of water per hour and has the ability to drive out oxygen to an amount of dissolved oxygen of 1.0 milligram per liter. An injection nozzle is provided at a portion where the nitrogen gas feed pipe 15 is coupled to the nitrogen gas injector 28, and high-pressure nitrogen gas is injected into water. In this injection nozzle, nitrogen replacement is more effective as the particles of nitrogen gas to be injected can be made finer. The water tank 30, the water outlet 31, the nitrogen water inlet 32, the circulation pump 20, the nitrogen gas injector 28, and the circulation pipes 21, 22, and 23 are closed with respect to water and gas (airtight state) ), Having a strength capable of withstanding a pressure of 0.5 megapascal. The circulation pump 20 takes out the water in the circulation pipes 21, 22, and 23 from the water tank 30 with a pressure of 0.5 megapascal, passes the nitrogen gas injector 28, and returns it to the water tank 30. The water outlet 31, the nitrogen water inlet 32, the circulation pump 20, and the circulation pipes 21, 22, and 23 constitute water circulation means between the water tank 20 and the nitrogen gas injector 28.

  In FIG. 1, the water tank 30 is depicted as if it is one tank for the sake of simplicity, but in reality, the same tank is provided in parallel with two tanks, a water outlet 31, An inlet 32, a gas outlet 33, a thermometer 35, and a dissolved oxygen meter 36 are provided in each of the two tanks. During normal operation, two tanks are used at the same time. However, during maintenance (cleaning, parts replacement, etc.), it is possible to stop only one tank and continue to operate the other one tank. A valve (not shown) is provided at the water outlet 31 and the nitrogen water inlet 32 to join the water taken out from the two tanks to the circulation pipe 21. Moreover, the nitrogen water thrown into the water tank from the circulation pipe 22 is thrown into two tanks.

  When two 10-ton water tanks (tank A and tank B) were provided in parallel, the nitrogen water in tank A was first removed and the amount of dissolved oxygen decreased to the target dissolved oxygen amount (for example, 1.0 milligram per liter). At that time, the nitrogen water in the tank A is sent to the ice making machine 40, and the production process of nitrogen ice is started. In the meantime, it is possible to use the nitrogen water production process in the B tank. It takes 10 hours to make all 20 tons into nitrogen water, but if it is 10 tons, it will be completed in 5 hours.

  A gas discharge port 33 is provided in the upper part of the water tank 30. This gas discharge port 33 is provided with a necessary check valve in order to maintain the airtightness of the water tank 30, and oxygen accumulated in the water tank (dissolved oxygen contained in the raw water, It plays the role of releasing oxygen) expelled from the inside of the nitrogen water. A thermometer 35 and a dissolved oxygen meter 36 are further provided in the water tank 30, and the pointers are provided at positions that are easy to see from the outside. In order to adjust the water temperature, it is desirable to attach a cooling device to the water tank 30. The lower the water temperature, the more gas will dissolve. That is, nitrogen replacement is more effective as the water to be replaced is cooled. It is desirable to manage at 5 degrees Celsius.

  After confirming that one of the two water tanks has reached the desired amount of dissolved oxygen, nitrogen water is sent to the ice making machine 40 via the ice making water supply pipe 34. The ice making water supply pipe 34 is provided between the lowermost part of each of the two water tanks and reaching the ice making machine 40, and if necessary, a cold insulation measure is taken to keep the temperature. The ice-making water supply pipe 34 does not need to have a pressure-resistant structure as much as the circulation pipes 21, 22, and 23. The process of making ice, breaking ice, storing ice, weighing, and shipping is performed in the atmosphere in one embodiment. Ice making, crushed ice and ice storage may be performed in a nitrogen gas atmosphere.

  The ice making machine 40 is selected to be capable of making ice in a short time. This is because nitrogen gas contained in a large amount of nitrogen water is confined in ice as it is. As the ice making machine 40, for example, the following is used. Nitrogen water is dripped from above in a state in which the metal plate is cooled to minus 25 degrees using a metal plate that is vertically set with both a cooling device and a heater. Adjust the speed at which the water is dripped so that it will freeze until the water drops down. If this operation is continued for about 20 minutes, ice on a plate with an appropriate thickness is formed. Therefore, stop dripping nitrogen water and stop cooling the metal plate. On the contrary, when the heater is operated, the plate-shaped ice peels off from the metal plate and falls. Nitrogen ice broken by the impact of the fall is further conveyed to the ice breaker 50 by a belt conveyor and further broken to an appropriate size. The crushed nitrogen ice is carried to the ice storage room 60.

  In the ice storage chamber 60, moderately sized ice is stored in the atmosphere, forming a mountain having a peak at the place where it falls from the belt conveyor. Appropriate cooling equipment will be provided to ensure proper temperature control for storing ice. Ice piled up in a mountain shape is leveled by a rake in the form of an electric rake. The nitrogen ice scraped off by the rake is weighed by a measuring instrument and shipped by a shipping device. At the time of shipment to the truck bed, the measured nitrogen ice is carried directly to the truck bed. In the case of shipment in a bag, for example, the bag is packed in a 20 kg bag and shipped.

  In the embodiment, a method using a polyimide hollow fiber membrane is used as a method for separating nitrogen from the atmosphere. However, as another method for extracting nitrogen gas, a method using molecular sieve charcoal is also known.

  When the full nitrogen water is sent to the ice making machine 40, the amount of water in the water tank decreases. It is desirable to send nitrogen gas into the empty space at that time. If the atmosphere itself is included, oxygen in the atmosphere may be dissolved.

  Ice confectionery can be produced by using seasoned water as water to be placed in the water tank. In that case, the ice making machine of the embodiment is replaced with an ice confectionery manufacturing apparatus.

  In the case of industrial ice cube manufacture, conventionally, in order to prevent ice cloudiness and to make transparent ice cubes, air pipes are placed in ice cans and air is injected during the ice making process. Yes. When ice cubes are made using the nitrogen water of the present invention, nitrogen replacement is further continued by injecting nitrogen gas instead of injecting air in an ice making process in which nitrogen water is put into an ice can and frozen. To produce nitrogen gas-filled ice. The ice cube production takes about 48 hours to prevent oxygen from dissolving in the air during that time.

  In the embodiment, the nitrogen ice production apparatus based on a large plant has been described. On the other hand, it is also possible to apply the nitrogen ice production apparatus according to the present invention as an ice making apparatus incorporated in a commercial or household freezer, a refrigerator or a refrigerator that is a refrigerator-freezer. Thereby, nitrogen ice can be automatically made in a cooling device for business use or home use. Some cooling devices for business use or home use already have a function of automatically making ice. The water tank and ice making machine in the existing ice making function are used as they are as the water tank and ice making machine of the nitrogen ice making apparatus of the present invention. The ice storage room can also be used as it is. Other components unique to the present invention, that is, a circulation pipe, a circulation pump, a nitrogen gas injector, and the like can be added and connected. Such commercial or household cooling equipment incorporating the nitrogen ice production apparatus as an ice making apparatus is also included in the scope of the present invention.

  In the commercial or household cooling apparatus in which the nitrogen ice manufacturing apparatus is incorporated as an ice making apparatus in the fifth embodiment, it is more preferable that the atmosphere of one or a plurality of chambers included in the cooling apparatus is replaced with nitrogen. The cooling device is usually provided with various rooms such as a freezing room, an ice storage room, a refrigerating room, a chilled room, and a vegetable room. In such a cooling device, a decompression unit that evacuates each chamber and a nitrogen gas supply unit that feeds nitrogen gas into each chamber are provided. Each chamber is opened only when a container such as food is taken out, and is normally sealed. Therefore, the air in each chamber can be replaced with nitrogen by supplying the nitrogen gas with the nitrogen gas supply device after the chamber is sealed and vacuumed by the decompression device. Thereby, the effect of preventing the oxidation of the contents in each chamber of the cooling device and maintaining the freshness can be obtained. As the decompression means, there is a vacuum pump or the like, and as the nitrogen gas supply means, a nitrogen gas extractor used for producing nitrogen ice may be used in combination.

  It can be used for ice making equipment on land and at sea. It can also be used in ice confectionery manufacturing equipment by using seasoned water as water to be put in the water tank. As the types of ice, it can be used for various ice production apparatuses such as ice cubes, block ice, plate ice, flake ice, and sherbet ice. It can also be used for ice making devices for stores and homes.

DESCRIPTION OF SYMBOLS 10 Air compressor 11 Compressed air feed pipe 14 Nitrogen gas extractor 15 Nitrogen gas feed pipe 21, 22, 23 Circulation pipe 20 Circulation pump 28 Nitrogen gas injector 30 Water tank 31 Water extraction port 32 Nitrogen water inlet 33 Gas discharge port 34 Ice making water pipe 35 Thermometer 36 Dissolved oxygen meter 40 Ice making machine 50 Ice breaker 60 Ice storage room 70 Measuring instrument 80 Shipping device

Claims (8)

A nitrogen ice production apparatus for producing nitrogen ice, which is ice obtained by freezing water obtained by replacing dissolved oxygen in water with nitrogen gas,
An airtight water tank (30) that blocks intrusion of gas from the surrounding atmosphere; and
A nitrogen gas injector (28) for injecting nitrogen gas into the passing water;
A nitrogen gas extractor (14) for extracting nitrogen gas from the atmosphere and supplying the extracted nitrogen gas to the nitrogen gas injector (28);
In order to change the water in the water tank (30) to water substituted with nitrogen gas, water is taken out from the water tank (30), passed through the nitrogen gas injector (28), and the water tank (30). Water circulation means (31, 20, 32, 22) for circulating water to return, and
An ice making machine (40) for producing nitrogen ice by freezing nitrogen-substituted water extracted from the water tank (30).   The nitrogen ice manufacturing apparatus according to claim 1, further comprising a cooling device for cooling water in the water tank (30).   It is a nitrogen ice manufacturing apparatus of Claim 1 or 2, Comprising: It has a means to send nitrogen gas with respect to the said ice maker (40), In the ice making process in the said ice maker (40), sending nitrogen gas, Nitrogen ice production apparatus characterized by performing ice making. It is a nitrogen ice manufacturing apparatus in any one of Claims 1-3,
The water tank (30) is composed of two tanks having the same function, and water can be circulated between the tanks and the nitrogen gas injector (28), and water substituted with nitrogen gas from each tank. The nitrogen ice production apparatus is characterized in that nitrogen ice can be produced with the ice making machine (40).   A cooling device that is a commercial or household freezer, refrigerator, or refrigerator-freezer, wherein the nitrogen ice production device according to any one of claims 1 to 4 is incorporated as an ice making device.   The cooling device according to claim 5, wherein one or more of a freezing room, an ice storage room, a refrigerated room, a chilled room, and a vegetable room, and a decompression unit that evacuates each of the one or more rooms, Nitrogen gas supply means for sending nitrogen gas to each of the one or more chambers, and after reducing the pressure by the pressure reducing means when each of the one or more chambers is sealed, the nitrogen gas is supplied by the nitrogen gas supply means The cooling device is characterized in that the atmosphere in the one or more indoors is replaced with nitrogen by supplying. It is a nitrogen ice manufacturing apparatus in any one of Claims 1-4,
An ice breaker (50) for breaking the nitrogen ice produced by the ice making machine (40);
An ice storage room (60) for storing nitrogen ice;
A scraping and leveling device that scrapes and smoothes the nitrogen ice stored in the ice storage chamber;
A meter (70) for weighing the nitrogen ice scraped by the scraper;
A nitrogen ice production apparatus, further comprising a shipping device (80) for shipping the nitrogen ice weighed by the weighing instrument. In order to produce nitrogen ice, which is ice that has been frozen by substituting nitrogen gas for dissolved oxygen in water,
An airtight water tank (30) that blocks intrusion of gas from the surrounding atmosphere; and
A nitrogen gas injector (28) for injecting nitrogen gas into the passing water;
A nitrogen gas extractor (14) for extracting nitrogen gas from the atmosphere and supplying the extracted nitrogen gas to the nitrogen gas injector (28);
In order to change the water in the water tank (30) to water substituted with nitrogen gas, water is taken out from the water tank (30), passed through the nitrogen gas injector (28), and the water tank (30). Water circulation means (31, 20, 32, 22) for circulating water to return, and
An ice making machine (40) for producing nitrogen ice by freezing nitrogen-substituted water taken out from the water tank (30), and a method for producing nitrogen ice using a nitrogen ice production apparatus comprising ,
Producing water in which dissolved oxygen is replaced with nitrogen gas by circulating the water in the water tank so that the water circulation means passes the nitrogen gas injector and returns to the water tank;
And a step of producing nitrogen ice by freezing the water substituted with nitrogen gas with the ice making machine.

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