JP6676871B2 - Ice making system and ice making method - Google Patents

Description

  The present invention relates to an ice making system and an ice making method.

  There is a technology for making sherbet ice used for maintaining freshness of marine products. For example, Patent Literature 1 discloses an ice generator that converts the incoming salt water into ice, sends it out, a small-capacity ice making tank for making ice of sherbet ice having a constant sherbet concentration, and a constant ice made by the ice making tank and the ice generator. An ice making tank for storing sherbet ice having a constant sherbet concentration, wherein the storage tank has a capacity larger than an ice making tank for storing sherbet ice having a constant sherbet concentration. A method is disclosed. Further, for example, Patent Literature 2 discloses a technology in which ice / slurry produced by a subcooler is stored in an ice storage tank.

Japanese Patent No. 5325510 JP 2009-168369 A

  As a technology for making sherbet ice used to maintain the freshness of marine products, the salt water supplied into the cooler is cooled by a coolant, and the ice making layer formed on the inner wall surface of the cooler is peeled off by a scraper to remove the ice. There is an ice generator to generate (for example, Patent Document 1). However, in this conventional ice generator, ice is generated by separating the ice making layer formed on the inner wall surface of the cooler with a scraper, so that the sherbet ice that is made has a diameter of ice crystal grains of about 0.2 mm. Met. In addition, since the ice making layer was peeled off with a scraper, the shape of ice crystal grains was likely to vary. Further, the ice crystal grains were easy to condense with each other and were easily enlarged. On the other hand, it is more preferable that sherbet ice used for maintaining freshness of marine products has a small diameter of ice crystal grains, uniform ice crystal grains, and is hard to be enlarged.

  In view of the above problems, an object of the present invention is to provide a technique for producing ice-water saltwater sherbet ice in which the diameter of the ice crystal grains is smaller than before, the ice crystal grains are uniform, and it is difficult to enlarge.

  SUMMARY OF THE INVENTION In order to solve the above-mentioned problems, the present invention applies supercooled ice making technology cultivated by the applicant for many years in ice storage for air conditioning to produce sherbet ice in salt water.

  Specifically, the present invention relates to an ice making device for making salt water in a supercooled state, releasing the supercooled salt water, and making sherbet ice having a crystal grain diameter of 0.01 to 0.1 mm, and the ice making device. And a supply device for storing sherbet ice having a diameter of 0.01 to 0.1 mm for storing sherbet ice produced by the method described above.

According to the sherbet ice making system according to the present invention, the diameter of the ice crystal grains of the sherbet ice that is made by supercooling and releasing the salt water is 0.01 to 0.1 mm. Can be made smaller than before. The diameter of the ice crystal grain means the maximum diameter when the ice crystal grain is not spherical. In addition, the sherbet ice made by the sherbet ice making system according to the present invention has a curved surface of ice crystal grains, is uniform, and hardly condenses with each other. As a result, the fluidity of the sherbet ice is better than before. For this reason, clogging of the piping and the like hardly occurs, and sherbet ice can be supplied with less power than before. Moreover, according to the ice making system for sherbet ice according to the present invention, the value of an ice packing factor (IPF) during ice storage can be made larger than before. Specifically, the IPF is 25 to 30% in the conventional technology for separating an ice making layer formed on the inner wall surface of the cooler with a scraper, but the IPF is 50 to 60% in the sherbet ice making system according to the present invention. can do. Therefore, the size of the ice storage tank can be made smaller than before. Further, according to the ice making system for sherbet ice according to the present invention, it is possible to make sherbet ice having a lower salt concentration than conventional ones. Specifically, in the conventional technology of removing the ice making layer formed on the inner wall surface of the cooler with a scraper, the corresponding salt concentration is 1.0 to 3.5% (3.5% corresponds to the seawater salt concentration). there were. On the other hand, in the ice making system for sherbet ice according to the present invention, ice making of sherbet ice having a salt concentration of less than 1% is also possible, and sherbet ice having an arbitrary salt concentration can be made. In addition, in the conventional technology of peeling off the ice making layer generated on the inner wall surface of the cooler with a scraper, the ice generator is likely to fail due to the load at the time of peeling, such as breakage of the blade of the scraper. Was concerned. In addition, the burden of maintenance was also a burden. On the other hand, in the ice making system for sherbet ice according to the present invention, since there is no load at the time of peeling, the system is less likely to fail and the maintenance is easy. Furthermore, by using sherbet ice produced by the ice making system for sherbet ice according to the present invention to maintain the freshness of marine products, the quality of marine products can be maintained longer than before.

  Sherbet ice can be suitably used for marine products that need to maintain freshness in salt water. Examples of marine products include fish (such as saury, tuna, horse mackerel, mackerel) and crustaceans (such as crab and shrimp). These are only examples, and the seafood is not limited to these.

  Here, the ice making device may put the seawater in a supercooled state and release the seawater in the supercooled state. ADVANTAGE OF THE INVENTION According to this invention, the sorbet ice of seawater can be made using seawater. The seawater is preferably sterilized seawater. Further, the seawater is more preferably sterilized seawater with adjusted salt content. Salt content can be adjusted by mixing fresh water with seawater. The concentration of the salt-adjusted sterilized seawater can be adjusted according to the marine product. The concentration of the sterilized seawater adjusted for salt can be lower than the seawater concentration (for example, 3.5%), for example, 3% or less.

  Further, the ice making device is connected to the outgoing pipe through which the salt water flows, a heat exchanger connected to the outgoing pipe to make the salt water in a supercooled state, a return pipe through which the supercooled salt water flows, and the return pipe. And a release device for releasing the supercooled salt water, wherein the supply device is an ice storage tank that stores the sherbet ice made by the ice making device, and a pump that pumps the stored sherbet ice. And a supply pipe connected to the ice storage tank and the pump, through which the sherbet ice flows.

  The outgoing pipe can be connected at one end to an ice storage tank and at the other end to a heat exchanger. Salt water from an ice storage tank can flow through the outgoing pipe. The salt water from the ice storage tank is obtained by reducing the temperature of the raw water by the ice storage tank. In the outgoing pipe, a pump of an ice making device that pumps up salt water in the ice storage tank and pumps it to the heat exchanger, a preheater that melts fine ice contained in the salt water from the ice storage tank, various valves, a thermometer, a flow meter, etc. May be further provided. The supercooled water pump may be controlled by an inverter to stabilize the flow rate supplied to the heat exchanger.

The heat exchanger exchanges heat between a supercooling medium (water, brine, etc.) supplied from the refrigerator and the salt water, and brings the salt water into a supercooled state. Various heat exchangers including a plate type and a shell-and-tube type can be used as the heat exchanger. The canceller cancels the supercooled state by, for example, ultrasonic waves . Instead Ri pipe is connected at one end to the heat exchanger, it is possible to connect the other end to the de-. The return pipe may further include at least one of various valves, a thermometer, a flow meter, and the like.

  The ice storage tank stores ice produced sherbet ice and may be configured to have a stirring unit. By having the stirring section, the ice storage tank can suppress the flocculation of ice contained in the sherbet ice and maintain the fluidity of the sherbet ice. In the sherbet ice making system according to the present invention, the IPF of the ice storage tank can be 50 to 60%. The stirrer can be configured to include a shaft, a wing connected to the shaft, and a motor that rotates the shaft. The ice storage tank includes a raw water inlet for receiving salt water (raw water), a raw water outlet for sending out raw water, an ice inlet for receiving sherbet ice, an ice outlet for sending out sherbet ice, and an ice outlet for discharging remaining sherbet ice. It can be. Further, the ice storage tank accommodates the sherbet ice in the tank in an area on the side of the ice outlet, and a partition portion through which the salt water can pass (for example, a plate-like object having a plurality of holes, a mesh-like object, , Etc.). By having a partition part, an ice storage tank can control that ice is mixed in salt water sent to a subcooler.

  The pump pumps the stored sherbet ice. Since the sherbet ice produced by the ice making system for sherbet ice according to the present invention has excellent fluidity, the pump according to the present invention can supply the sherbet ice with less power than before. Further, the pump according to the present invention does not need to be a dedicated pump for pumping a slurry liquid, and a general-purpose pump for pumping water can be used. One end of the supply pipe is connected to the release device, the other end is connected to the supply destination, and an ice storage tank or a pump can be provided in the middle of the pipe. The supply pipe includes a first supply pipe having one end connected to the release device and the other end connected to the ice storage tank, and a second supply pipe having one end connected to the water storage tank and the other end connected to the supply destination. May be. The supply pipe may be further provided with at least one of various valves, a thermometer, a flow meter, and the like.

  The ice making system for sherbet ice according to the present invention includes an ice making device, a supply device, a heat exchanger and a canceller that constitute the ice making device, an ice storage tank and a pump that constitute the supply device, and a control unit that controls various valves and the like. A configuration may be further provided.

  The present invention can be specified as the ice making device described above. Further, the present invention can be specified as the supply device described above.

  Here, the present invention can also be specified as an ice making method for sherbet ice. For example, the present invention provides an ice making step of making salt water supercooled, releasing the salt water in the supercooled state, and making sherbet ice having an ice crystal grain diameter of 0.01 to 0.1 mm, and ice making in the ice making step. And supplying a sherbet ice having a diameter of 0.01 to 0.1 mm.

ADVANTAGE OF THE INVENTION According to the ice making method of the sherbet ice concerning this invention, the diameter of an ice crystal grain can be made smaller than before. Further, the sherbet ice produced by the method for producing sherbet ice according to the present invention has a uniform shape and size of ice crystal grains, and is unlikely to be flocculated with each other, so that it is difficult to enlarge. As a result, the fluidity of the sherbet ice is better than before, the clogging of pipes and the like is less likely to occur, and the sherbet ice can be supplied with less power than before. Further, the value of the ice filling factor (IPF) at the time of storing ice can be made larger than before. Further, it is possible to produce sherbet ice having a lower salt concentration than before. Furthermore, by using sherbet ice produced by the method for making sherbet ice according to the present invention to maintain the freshness of marine products and the like, the quality of marine products and the like can be maintained longer than before. The method for making ice of sherbet ice according to the present invention may simply include the above-mentioned ice making step. Moreover, the method for making ice of sherbet ice according to the present invention may simply include the above-described supply step.

  In the ice making step, the seawater may be supercooled, and the supercooled seawater may be released. ADVANTAGE OF THE INVENTION According to this invention, the sorbet ice of seawater can be made using seawater. The seawater is preferably sterilized seawater. Further, the seawater is more preferably sterilized seawater with adjusted salt content. Salt content can be adjusted by mixing fresh water with seawater. The concentration of the salt-adjusted sterilized seawater can be adjusted according to the marine product. The concentration of the salt adjusted sterilized seawater can be lower than the seawater concentration (for example, 3.5%), for example, within 3%.

  ADVANTAGE OF THE INVENTION According to this invention, the diameter of an ice crystal grain is smaller than before, the ice crystal grain is uniform, and the technique of making the sherbet ice of salt water which is hard to enlarge can be provided.

1 is a block diagram of an ice making system for sherbet ice according to an embodiment. 1 shows an enlarged sectional view of an ice storage tank according to an embodiment. 3 shows an operation flow of the ice making system for sherbet ice according to the embodiment. FIG. 7 is a block diagram of a sherbet ice making system according to a modification. 4 shows a photographed image (magnification: 500 times) of sherbet ice made by the sherbet ice making system according to the embodiment. 2 shows a photographed image (magnification: 150 times) of sherbet ice made by the sherbet ice making system according to the embodiment. 5 shows a photographed image (magnification: 500 times) of sherbet ice made on the assumption of a conventional scraping ice making method. FIG. 8 shows an enlarged view of the right side of FIG. 7.

  Next, an embodiment of the present invention will be described with reference to the drawings. In the following description, a case where sherbet ice made by the sherbet ice making system 1 according to the embodiment is used for maintaining freshness of marine products and the like will be described as an example. Examples of marine products include fish (such as saury, tuna, horse mackerel, mackerel) and crustaceans (such as crab and shrimp). These are only examples, and the seafood is not limited to these. Further, the embodiments described below are merely examples, and the present invention is not limited to the embodiments described below.

<Sherbet ice making system>
In the ice making system 1 for sherbet ice according to the embodiment, the seawater is supercooled, the supercooled seawater is released, and the diameter of the ice crystal grains is 0.01 to 0.1 mm (0.05 mm in the present embodiment). Ice making device 2 for making sherbet ice, and sherbet ice made by the ice making device 2 are stored, and the diameter of the ice crystal grains is 0.01 to 0.1 mm ( In the present embodiment, a supply device 3 for supplying sherbet ice (containing a lot of ice crystal grains of about 0.05 mm) and a control device 5 for controlling the ice making device 2 and the supply device 3 are provided. The sherbet ice making system 1 according to the embodiment may be configured to further include a refrigerator 4. The diameter of the ice crystal grain means the maximum diameter when the ice crystal grain is not spherical (for example, an ellipsoid).

  The main components of the ice making device 2 are an outgoing pipe 21, a return pipe 22, an ice making device pump 23, a preheater 24, an ice making device filter 25, a heat exchanger 26, and a release device 27. The supply device 3 mainly includes a water supply pipe 31, a supply pipe 32 (first supply pipe 321 and a second supply pipe 322), an ice storage tank 33, and a pump 34 of the supply apparatus. Hereinafter, each of the above configurations will be described along the flow of seawater supply, supercooling, release, and sherbet ice supply.

<< water supply pipe >>
One end of the water supply pipe 31 is connected to the seawater treatment device 6, and the other end is connected to the upper part of the ice storage tank 33, through which seawater flows. The seawater treatment device 6 mixes sterilized seawater and fresh water to generate sterilized seawater having a salt concentration of 0 to 3%. As the seawater treatment device 6, existing equipment installed in a fishing port or the like can be used. The seawater treatment device 6 can be configured to include, for example, a salt concentration adjusting tank, a salt concentration setting device, a fresh water amount adjusting valve, a pump for supplying seawater, and a solid-liquid separation filter. The salt concentration adjusting tank is filled with the sterilized seawater, the fresh water adjusting valve is opened based on the salt concentration (0 to 3%) set by the salt concentration setting device, and a predetermined amount of fresh water is introduced. As a result, sterilized seawater having a salt concentration of 3% or less, which is lower than the seawater concentration (for example, 3.5%), is generated.

  In the water supply pipe 31, an automatic valve 35 of the seawater supply device and a filter 36 of the seawater supply device are provided in order from the upstream side in the flow of the seawater. The automatic valve 35 of the seawater supply device is controlled by the control device 5 and, when filling the ice storage tank 33 with seawater, opens when the water level of the ice storage tank 33 decreases and closes when the water level increases. The water level of the ice storage tank 33 can be obtained by a water level gauge provided in the ice storage tank 33 described later. The filter 36 of the seawater supply device is configured by, for example, a filter having a filtration diameter of 20 μm, and captures impurities contained in seawater. Impurities are solids that can be harmful in ice making, in other words, can be triggers to release supercooled seawater. Examples of the impurities include small pieces of seaweed and sand.

<< Ice storage tank >>
The ice storage tank 33 receives seawater and stores the iced sherbet ice. Here, FIG. 2 is an enlarged sectional view of the ice storage tank according to the embodiment. The ice storage tank 33 includes a housing 331, a shaft 332, wings 333, a motor 334, a punching plate 335, a seawater receiving port 336, a seawater outlet 337, an ice receiving port 338, an ice transmitting port 339, an outlet 340, and a water level gauge 341. Including. The shaft 332, the wings 333, and the motor 334 constitute a stirring unit of the present invention. The housing 331 has a cylindrical side wall 342, a circular lid 343, and a bottom 344, and stores sherbet ice with seawater inside. The shaft 332 extends vertically downward from the lid 343 to a height that does not contact the punching plate 335. The shaft 332 is provided at a position eccentric from the center of the housing 331 in order to improve the stirring performance. The wings 333 stir the sherbet ice. The wings 333 are composed of a pair of left and right wings around a shaft 332, and are provided at two locations vertically. The lower wing 333 is provided near the punching plate 335. Here, the seawater in the ice storage tank 33 is pumped up by the pump 23 of the ice making device, and a vertically downward suction force acts near the punching plate 335. Therefore, sherbet ice easily accumulates in the vicinity of the punching plate 335. If the gap between the lower end of the lower wing 333 and the punching plate 335 is large, there is a concern that sufficient stirring may not be achieved. In the present embodiment, by providing the lower wing 333 near the punching plate 335, the sherbet ice can be sufficiently stirred. The upper wing 333 is provided near the middle between the lower wing 333 and the lid 343. The shape, size, number of the wings 333, and the like are not limited to the above. The motor 334 is provided on the cover 343 and rotates the shaft 332. The control device 5 controls ON / OFF and the rotation speed of the motor 334.

The punching plate 335 corresponds to the partitioning portion of the present invention, and accommodates the sherbet ice in the ice storage tank 33 in the area on the side of the ice outlet 339, and allows seawater to pass through a plurality of holes formed in the punching plate 335. . The punching plate 335 has a circular shape substantially the same size as the inner diameter of the housing 331, and has a hole diameter of 0.8 mm and an aperture ratio of 24%. The diameter and aperture ratio of the hole are examples, and for example, the diameter of the hole can be 0.3 to 2.0 mm, and the aperture ratio can be 20 to 30%. The punching plate 335 is provided near the upper side of the seawater outlet 337 provided near the bottom 344. The position of the punching plate 335 is not limited to the above, but is preferably lower than the center in the vertical direction of the ice storage tank 33 in order to secure an IPF of 50 to 60% in the ice storage tank 33. Preferably, it is above the seawater outlet 337 provided near 344. Instead of the punching plate 335, a mesh structure (for example, a mesh) may be used. The reticulated structure may be a planar one or a three-dimensional one. A three-dimensional structure is exemplified by a three-dimensional network structure (for example, a sintered metal filter). Further, the punching plate 335 and the mesh structure may be appropriately combined and arranged.

  Seawater receiving port 336 is provided on lid 343 and is connected to water supply pipe 31 to receive seawater. The seawater receiving port 336 may be provided on the side wall 342 of the ice storage tank 33. The seawater receiving port 336 only needs to be provided above the water surface when the water storage tank 33 is full, and the installation position is not limited to the above. The seawater outlet 337 is provided near the bottom 344 in the side wall 342 and is connected to the outgoing pipe 21 to send out seawater. The ice receiving port 338 is provided near the lid 343 on the side wall 342, is connected to the return pipe 22, and receives the sherbet ice. The ice receiving port 338 can be provided in the lid 343, for example. The ice outlet 339 is provided on the upper side in the vicinity of the punching plate 335, is connected to the supply pipe 32 (second supply pipe 322), and sends out sherbet ice having a diameter of ice crystal grains of 0.01 to 0.1 mm. The ice outlet 339 only needs to be provided at least above the vicinity of the punching plate 335, and a plurality of ice outlets 339 may be provided. The discharge port 340 is provided at the bottom 344 and is connected to the discharge pipe 37 to discharge water or sherbet ice in the ice storage tank 33. The discharge pipe 37 is provided with an automatic valve 38 for discharging. The automatic discharge valve 38 is controlled by the control device 5 and is opened before receiving seawater, discharges water and sherbet ice in the ice storage tank 33, and discharges all water and sherbet ice in the ice storage tank 33. And it is closed. The water level gauge 341 is provided in the ice storage tank 33 and measures the level of seawater in the ice storage tank 33. An existing sensor such as a water level sensor can be used as appropriate for the water level meter 341.

<< Going piping >>
One end of the outgoing pipe 21 is connected to the seawater outlet 337 of the ice storage tank 33, and the other end is connected to the heat exchanger 26, and the seawater cooled in the ice storage tank 33 flows. The outgoing pipe 21 is provided with a pump 23 of the ice making device, a preheater 24, and a filter 25 of the ice making device in order from the upstream side in the seawater flow. The pump 23 of the ice making device pumps seawater from the ice storage tank 33 and pumps the seawater to the heat exchanger 26. The pump 23 of the ice making device includes a gate valve and can control the inverter by the control device 5 in order to stabilize the flow rate of seawater supplied to the heat exchanger 26. The control device 5 stabilizes the flow rate of the seawater supplied to the heat exchanger 26 based on the flow rate information of the seawater obtained from the flow meter M1 provided between the heat exchanger 26 and the pump 23 of the ice making device. Adjust the opening of the gate valve and the pressure of the pump so that

The preheater 24 melts fine ice contained in seawater from the ice storage tank 33. The preheater 24 can be constituted by a heater, and ON / OFF and a heating temperature are controlled by the control device 5. The control device 5 sets the temperature of the seawater supplied to the heat exchanger 26 to a predetermined temperature (for example, based on the seawater temperature information acquired from the temperature sensor T3 provided between the heat exchanger 26 and the preheater 24). , 0 ° C.). For example, when the temperature of the seawater is lower than the predetermined temperature, the control device 5 increases the heating temperature of the preheater 24. Further, for example, when the temperature of the seawater is higher than the predetermined temperature, the control device 5 lowers the heating temperature of the preheater 24. The predetermined temperature can be determined in advance by experiments or the like according to the concentration of seawater and the like. The filter 25 of the ice making device captures condensed ice and impurities contained in seawater. Examples of the impurities include small pieces of seaweed, sand, and fine ice particles.

  The heat exchanger 26 is connected to the outgoing pipe 21 connected to the ice storage tank 33 and the return pipe 22 connected to the canceler 27, and further connected to the brine outgoing pipe 42 and the brine return pipe 43 connected to the refrigerator 4; Heat is exchanged between the brine as the supercooling medium supplied from the refrigerator 4 and seawater to bring the seawater into a supercooled state. The heat exchanger 26 is constituted by a plate-type heat exchanger. As the heat exchanger 26, various existing heat exchangers such as a shell-and-tube heat exchanger can be used.

<< refrigerator >>
The refrigerator 4 cools the brine. The temperature of the brine is, for example, −6 ° C. before heat exchange and −3 ° C. after heat exchange. The refrigerator 4 is controlled by the control device 5. The control device 5 adjusts ON / OFF and cooling temperature based on brine flow rate information detected by a flow meter M2 described later, brine temperatures detected by temperature sensors T1 and T2 described later, and the like. One end of the brine going pipe 42 is connected to the refrigerator 4, and the other end is connected to the heat exchanger 26, cooled by the refrigerator 4, and the brine before heat exchange flows. A brine pump 41, a flow meter M <b> 2, and a temperature sensor T <b> 1 are provided in the brine going pipe 42 in order from the upstream side in the brine flow. The brine pump 41 pumps the brine cooled by the refrigerator 4 to the heat exchanger 26. The brine pump 41 includes a gate valve, and the flow rate of the brine can be controlled by the control device 5. The flow meter M2 detects a flow rate of the brine flowing through the brine going pipe 42. The temperature sensor T1 detects the temperature of the brine flowing through the outgoing pipe 42 of the brine.

  One end of the return pipe 43 of the brine is connected to the heat exchanger 26, and the other end is connected to the refrigerator 4, and the brine after the heat exchange flows. The brine return pipe 43 is provided with a temperature sensor T2. The temperature sensor T2 detects the temperature of the brine flowing through the return pipe 43 of the brine. The IPF is calculated based on the flow rate of the brine and the temperature of the brine detected by the flow meter M1 and the temperature sensors T1 and T2.

<< Unlocker >>
One end of the return pipe 22 is connected to the heat exchanger 26, and the other end is connected to the release unit 27, and the supercooled seawater flows. The canceller 27 cancels the supercooled state by ultrasonic waves. The canceler 27 is not limited to the above as long as it can cancel the supercooled state.

<< Supply piping >>
The supply pipe 32 includes a first supply pipe 321 and a second supply pipe 322. One end of the first supply pipe 321 is connected to the release unit 27, and the other end is connected to the ice storage tank 33, and the sherbet ice released by the release unit 27 flows. One end of the second supply pipe 322 is connected to the ice storage tank 33 and the other end is connected to the supply destination, and the sherbet ice of the IPF 50 to 60% stored in the ice storage tank 33 flows. The supply destination of the present embodiment is a water tank provided on a ship for maintaining freshness of marine products. The supply destination is not limited to the above as long as it is a place required to maintain the freshness of the marine product. The second supply pipe 322 is provided with a pump 34 of the ice supply device and an automatic valve 39 of the ice supply device in order from the upstream side in the flow of the sherbet ice.

The pump 34 of the ice supply device pumps sherbet ice from the ice storage tank 33 and pumps it to the supply destination. The pump 34 of the ice supply device includes a gate valve, and can be controlled by the control device 5. The control device 5 adjusts the opening of the gate valve and the pressure of the pump. Automatic valve 39 of the ice supply device
Is controlled by the control device 5, and when an instruction to start supply (switch ON) is made in a state where the ice storage tank 33 is filled with sherbet ice, the ice storage tank 33 is opened and the sherbet ice disappears or an instruction to stop supply (switch OFF). When it becomes, it is closed.

  The control device 5 controls various devices and devices of the ice making system for sherbet ice. The control device 5 includes a CPU (Central Processing Unit), a memory, an operation unit, a display unit, and the like, and controls various devices and devices by the CPU executing a control program stored in the memory. The control device 5 can be configured by a PLC (programmable logic controller), for example.

<Operation>
Next, the operation of the sherbet ice making system 1 according to the embodiment will be described together with the control processing by the control device 5. FIG. 3 shows an operation flow of the sherbet ice making system according to the embodiment.

<< Seawater filling >>
In step S01, the ice storage tank 33 is filled with seawater. The control device 5 opens the automatic discharge valve 38 to discharge the remaining seawater in the ice storage tank 33. This can suppress an increase in salt concentration in seawater, which is a concern due to repeated ice making. The control device 5 acquires the water level information from the water level gauge 341 of the ice storage tank 33, and closes the automatic discharge valve 38 when the seawater level in the ice storage tank 33 drops below a predetermined water level (empty state). . Next, the control device 5 opens the automatic valve 35 of the seawater supply device. The seawater to the ice storage tank 33 can be pumped by a pump of the seawater treatment device provided on the seawater treatment device 6 side. Thereby, sterilized seawater (for example, 20 ° C.) having a salt concentration of 0 to 3% is pumped. As the seawater passes through the filter 36 of the seawater supply device, impurities (for example, small pieces of seaweed and sand) contained in the seawater are captured. The control device 5 acquires the water level information from the water level gauge 341 of the ice storage tank 33, and closes the automatic discharge valve 38 when the water level of the seawater in the ice storage tank 33 rises above a predetermined water level. Note that the salt concentration in the ice storage tank 33 may be obtained. In this case, the control device 5 may turn on the motor 334 to rotate the wings 333 to stir the seawater.

<<<< ice making >>
In step S02, sherbet ice is made. The control device 5 turns on the pump 23 of the ice making device, pumps up the seawater in the ice storage tank 33 and sends it to the heat exchanger 26 under pressure. The controller 5 stabilizes the flow rate of seawater supplied to the heat exchanger 26 based on the flow rate information of seawater obtained from the flow meter M1 in order to stabilize the flow rate of seawater supplied to the heat exchanger 26. The inverter 23 controls the pump 23 of the ice making device. Further, the control device 5 controls the preheater 24 based on the seawater temperature information acquired from the temperature sensor T3 such that the temperature of the seawater supplied to the heat exchanger 26 is maintained at a predetermined temperature (for example, 0 degrees). Control. When the temperature of the seawater is lower than the predetermined temperature, control device 5 increases the heating temperature of preheater 24. Further, for example, when the temperature of the seawater is higher than the predetermined temperature, the control device 5 lowers the heating temperature of the preheater 24. By passing the seawater through the filter 25 of the ice making device, condensed ice and impurities contained in the seawater are captured. Examples of the impurities include small pieces of seaweed, sand, and fine ice particles.

  The seawater that has passed through the filter 25 of the ice making device exchanges heat with the brine supplied from the refrigerator 4 by the heat exchanger 26, and is cooled to a supercooled state with a supercooling degree of about 2 deg. For example, the seawater is cooled by the heat exchanger 26 from −2.5 ° C. to −5 ° C. The supercooled state of the seawater in the supercooled state is released by the ultrasonic wave of the canceller 27. The control device 5 can also perform ON / OFF of the refrigerator 4 and the canceller 27.

The sherbet ice produced by releasing the supercooled state flows through the first supply pipe 321 and is pumped to the ice storage tank 33. The control device 5 calculates the IPF in the ice storage tank 33 from the calorific value of the refrigerator 4 and turns on the motor 334 according to the IPF to rotate the blade 333. The IPF can be calculated by the following Expressions 1, 2, and 3. The calculation of the IPF is started, for example, when the temperature of the seawater sent from the ice storage tank 33 reaches a predetermined temperature (0 ° C.). First, the integrated heat generation amount is calculated by Expression 1. In Equation 1, the flow rate is obtained by a flow meter M1 provided in the outgoing pipe 42 of the brine. Tbr-out is acquired by the temperature sensor T2 provided in the return pipe 43 of the brine. Tbr-in is acquired by the temperature sensor T1 provided in the outgoing pipe 42 of the brine. Cp is the specific heat at constant pressure of the brine, ρ is the density of the brine, and these are obtained as the physical properties of the brine. The SCP generation power is the power of the pump 23 of the ice making device, and t is time.
Cumulative heat generation = flow rate × (Tbr-out-Tbr-in) × Cp × ρ × t-preheat heat-SCP generated power × t + previous heat heat accumulation ...

The preheat amount in Expression 1 is calculated by Expression 2. In Expression 2, TSC-in is acquired by a temperature sensor T3 provided on the downstream side (on the heat exchanger 26 side) of the outgoing pipe 21, and Ttank-out is obtained on the upstream side of the outgoing pipe 21 (on the ice storage tank 33 side). Is obtained by the temperature sensor T4 provided in the first stage. Cpw is the specific heat at constant pressure of water, ρw is the density of water, and these are obtained as physical properties of water.
Preheating amount = supercooling water flow rate × (TSC-in-Ttank-out) × Cpw × ρw × t (2)

IPF is calculated based on the integrated heat generation amount calculated from Expressions 1 and 2. In Equation 3, the tank water amount is the amount of water in the ice storage tank 33, ρw is the constant pressure specific heat of water, and L is the latent heat of solidification of water (the amount of heat required for all the water in the ice storage tank 33 to become ice).
IPF = Integrated heat generation amount / (Tank water amount × ρw × L) Equation 3

  When the calculated IPF reaches a predetermined value (for example, 50%), the control device 5 ends the ice making. Specifically, the control device 5 turns off the pump 23, the refrigerator 4, and the canceller 27 of the ice making device, and ends the ice making.

<< supply >>
In step S03, sherbet ice is supplied. When the control device 5 receives a supply start instruction (for example, a switch provided on the operation unit of the control device 5) in a state where the ice storage tank 33 is filled with the sherbet ice, the automatic valve 39 of the ice supply device is opened. State. As a result, sherbet ice having an IPF of 50 to 60% and an ice crystal grain diameter of 0.01 to 0.1 mm flows through the second supply pipe 322 and is pumped to the supply destination. In addition, the control device 5 acquires water level information from the water level gauge 341, and the level of seawater in the ice storage tank 33 becomes equal to or lower than a predetermined level (empty state) or an instruction to stop supply (for example, to the operation unit of the control device, When the provided switch OFF) is received, the automatic valve 39 of the ice supply device is closed. Thereby, the supply of the sherbet ice having the diameter of the ice crystal grains of 0.01 to 0.1 mm is completed. When the step S03 is completed, the step S01 is started again.

<Effect>
According to the ice making system 1 for sherbet ice according to the embodiment described above, by supercooling and releasing seawater, the diameter of ice crystal grains of sherbet ice to be iced becomes 0.01 to 0.1 mm, The diameter of the ice crystal grains can be made smaller than before. In addition, the sherbet ice made by the sherbet ice making system 1 according to the embodiment has a curved surface of ice crystal grains, and the ice crystals are uniform, and the ice crystal grains are hardly condensed. As a result, the fluidity of the sherbet ice is better than before. For this reason, clogging of the piping and the like hardly occurs, and sherbet ice can be supplied with less power than before. Further, the pump 34 of the supply device does not need to be a dedicated pump for pumping the slurry liquid, and a general-purpose pump for pumping water can be used. Further, according to the ice making system 1 for sherbet ice according to the embodiment, the value of IPF can be made larger than before. Specifically, the IPF is 25 to 30% in the conventional technology for separating the ice making layer generated on the inner wall surface of the cooler with a scraper, but the IPF is 50 to 60% in the sherbet ice ice making system 1 according to the embodiment. It can be. Therefore, the size of the ice storage tank 33 can be reduced as compared with the related art. Alternatively, more sherbet ice can be stored than before.

  Further, according to the ice making system 1 for sherbet ice according to the embodiment, sherbet ice having a lower salt concentration than conventional can be made. Specifically, in the conventional technology of peeling off the ice making layer formed on the inner wall surface of the cooler with a scraper, the corresponding salt concentration is 1.0 to 3.5% (3.5% corresponds to the salt concentration of seawater). there were. In contrast, the sherbet ice making system 1 according to the embodiment can also make sherbet ice having a salt concentration of less than 1%, and can make sherbet ice having an arbitrary salt concentration. In addition, in the conventional technology of peeling off the ice making layer generated on the inner wall surface of the cooler with a scraper, it is considered that the load at the time of peeling, such as breakage of the blade of the scraper, is likely to cause a failure of the ice generator. Was concerned. In addition, the burden of maintenance was also a burden. On the other hand, in the ice making system 1 for sherbet ice according to the embodiment, since there is no load at the time of peeling, there are few system failures and maintenance is easy. Furthermore, by using the sherbet ice produced by the sherbet ice making system 1 according to the embodiment for maintaining the freshness of marine products, the quality of marine products can be maintained longer than before.

  According to the ice storage tank 33 according to the embodiment, the sherbet ice is accommodated in the region on the side of the stirring unit (the shaft 332, the blade 333, the motor 334) by the punching plate 335, so that the ice particles are also stirred. The blade 333 and the motor 334) can be accommodated in the area. As a result, the flow of the ice particles into the ice making system 1 can be suppressed, and the freezing in the heat exchanger 26 and the occurrence of blockage in the pipe (for example, the outgoing pipe 21) can be suppressed. Therefore, stable ice making can be performed. Further, according to the ice storage tank 33 according to the embodiment, since the flow of the ice particles into the ice making system 1 can be suppressed, it is possible to stir the ice during the ice making, and to make the ice making stable as described above. It can be performed. As a result, the efficiency of ice making can be improved. In addition, when stirring was stopped during ice making and stirring was started when supplying sherbet ice, there was a concern that the load at the start of stirring was large. On the other hand, according to the ice storage tank 33 according to the embodiment, the load does not increase when stirring is started. Further, in the prior art, in order to avoid an increase in the load at the start of stirring, it was necessary to suppress the value of IPF during ice storage to about 30%. On the other hand, in the ice making system 1 for sherbet ice according to the present embodiment, the IPF can be reduced to 50 to 60%. Therefore, the size of the ice storage tank can be made smaller than before. Alternatively, more sherbet ice can be stored than before.

<Modification>
FIG. 4 shows a block diagram of a sherbet ice making system according to a modification. Around the heat exchanger 26, the pipe may freeze or block. Therefore, in the ice making system 1 for sherbet ice according to the modified example, a bypass pipe 61 is further provided near the heat exchanger 26, and a flow rate flowing through the return pipe 22 and a flow rate flowing through the bypass pipe 61 are detected. Detect freezing and blockage. Then, when freezing is detected, the heater is heated, and when blockage is detected, water is passed. The same components as those in the embodiment are denoted by the same reference numerals, and description thereof will be omitted.

As shown in FIG. 4, the bypass pipe 61 is connected to the outgoing pipe 21 near the heat exchanger 26.
And the return pipe 22. Further, a flow meter M3 is provided in the bypass pipe 61. Further, a heater 45 is provided in the outgoing pipe 42 of the brine.

  The control device 5 acquires the supercooled water main flow rate G1 from the flow meter M1 near the heat exchanger 26 of the return pipe 22 and acquires the bypass flow rate G2 from the flow meter M3 of the bypass pipe 61. The controller 5 detects that freezing has occurred when the subcooling water main flow rate G1 <rated 90% and G2> rated 120%. In this case, the control device 5 turns off the pump 4 of the refrigerator 4 and the ice making device, turns on the heater 45, and allows the brine heated by the heater 45 to flow through the heat exchanger 26 to melt the frozen portion. . In addition, when the supercooling water main flow rate G1 <rated 100% and G2 <rated 90%, the control device 5 detects that blockage has occurred. In this case, the control device 5 turns off the refrigerator 4 and allows supercooled water to flow therethrough to wash out the closed portion.

  According to the ice making system 1 for sherbet ice according to the modified example, it is possible to detect freezing or blockage of the pipe around the heat exchanger 26. Even if freezing or blockage is detected, the freezing or blockage can be resolved.

<Example>
A confirmation test of sherbet ice produced by the sherbet ice making system 1 according to the embodiment will be described. In the confirmation test, the sherbet ice formed by cooling salt water having a salt concentration of 2.5% at a supercooling degree of 2K and then releasing was observed and photographed with a microscope, and the diameter of ice crystal grains was actually measured from the photographed image. Further, as a comparative example, sherbet ice made by assuming a conventional scraping ice making method was photographed. Specifically, ice was generated by pouring fresh water on a cooled metal plate, shaved off with a blade, and then poured into salt water to form a sherbet-like shape, which was observed and photographed with a microscope. In this comparative example, ice was generated by applying fresh water to a cooled metal plate, but ice generated by applying fresh water and ice generated by applying salt water have, in principle, only fresh water components. It is still the same as ice, and it is thought that it can be considered as the same condition.

  Here, FIG. 5 shows a photographed image (magnification: 500 times) of sherbet ice made by the sherbet ice making system 1 according to the embodiment. FIG. 6 shows a photographed image (magnification: 150 times) of sherbet ice made by the sherbet ice making system 1 according to the embodiment. On the other hand, FIG. 7 shows a photographed image (magnification: 500 times) of sherbet ice made on the assumption of a conventional scraping type ice making method. The left side of FIG. 7 shows the state immediately after the scraping, and the right side of FIG. 7 shows the state 10 minutes after the scraping and stirring. FIG. 8 is an enlarged view of the right side of FIG.

  As shown in FIG. 5, according to the sherbet ice making system 1 according to the embodiment, sherbet ice having a curved surface and a diameter of ice crystal grains of 0.01 to 0.1 mm is produced. Was confirmed. In addition, as shown in FIG. 6, according to the ice making system 1 for sherbet ice according to the embodiment, it was confirmed that ice crystal grains having a diameter of 0.01 to 0.1 mm were uniformly dispersed. On the other hand, in the comparative example, as shown in the left diagram of FIG. 7, ice crystal grains of sherbet ice made assuming a conventional scraping type ice making method have a diameter of 0.1 to 0.2 mm, It was confirmed that the crystal grains were unevenly dispersed. Further, as shown in the right diagram of FIG. 7 and FIG. 8, the ice crystal grains of sherbet ice made on the assumption of the conventional scraping type ice making method are likely to combine with adjacent ice crystal grains and become enlarged. It was confirmed that it was easy. From the above, the ice crystal grains of the sherbet ice made by the sherbet ice making system 1 according to the embodiment are compared with the ice crystal grains of the sherbet ice made by assuming a conventional scraping type ice making method. It was confirmed that the diameter was small, the grains were uniform, and the curved surface was uniform and smooth. It is considered that the small diameter, the uniform grain, the uniform curved surface and the smoothness of the surface make it difficult for the ice crystal grains to condense and enlarge.

The various contents described above can be combined as much as possible without departing from the technical idea of the present invention. For example, in the above-described embodiment, an example in which the supply step is performed after the ice making step is completed, but the supply step may be performed while performing the ice making step. Driving variations are increased, and convenience is improved. Further, for example, in the above-described embodiment, the case where ice is made from sherbet ice from seawater and used to maintain freshness of marine products and the like has been described as an example, but ice is made from sherbet ice from fresh water and used to maintain freshness of vegetables and the like. Is also good.

DESCRIPTION OF SYMBOLS 1 ... Ice making system 2 ... Ice making device 26 ... Heat exchanger 27 ... Release device 3 ... Supply device 33 ... Ice storage tank 335 ... Punching plate 4 ... Refrigerator 5 ... Control device 6 ... Seawater treatment device

Claims (3)

An ice maker that makes the salt water supercooled, releases the salt water in the supercooled state, and makes sherbet ice having a diameter of ice crystal grains of 0.01 to 0.1 mm,
A supply device that stores sherbet ice produced by the ice making device, and supplies sherbet ice made in the ice making device with ice crystal grains having a diameter of 0.01 to 0.1 mm,
A control device for ending the ice making of the ice making device when the IPF of the ice storage tank of the supply device becomes 50 to 60%,
The ice making device has a piping path for pumping salt water from a lower part of the ice storage tank with a pump and pumping the salt water to an upper part of the ice storage tank , and supersonic cooling of the salt water by ultrasonic waves of a canceler provided in the middle of the piping path. Release the state,
Sherbet ice making system. The ice making device is connected to the outgoing pipe through which the salt water flows, a heat exchanger connected to the outgoing pipe to make the salt water in a supercooled state, a return pipe through which the supercooled salt water flows, and the return pipe, And a release device for releasing the salt water in the supercooled state,
An ice storage tank that stores the sherbet ice produced by the ice making device, a pump that pumps the stored sherbet ice, a supply pipe connected to the ice storage tank and the pump, and through which the sherbet ice flows. The ice making system for sherbet ice according to claim 1, comprising: An ice making step of making the salt water supercooled, releasing the salt water in the supercooled state, and making sherbet ice having a crystal grain diameter of 0.01 to 0.1 mm,
A supply step of storing sherbet ice produced in the ice making step, and supplying sherbet ice made in the ice making step with ice crystal grains having a diameter of 0.01 to 0.1 mm;
A control step of terminating the ice making step when the IPF of the ice storage tank used in the supply step becomes 50 to 60%;
With
In the ice making step, the supercooled state of the salt water is released by ultrasonic waves of a canceler provided in the middle of a piping path that pumps salt water from the lower part of the ice storage tank with a pump and pumps the salt water to the upper part of the ice storage tank ,
How to make sherbet ice.