WO2004046624A1 - Ice slurry generator - Google Patents

Ice slurry generator Download PDF

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Publication number
WO2004046624A1
WO2004046624A1 PCT/KR2003/002397 KR0302397W WO2004046624A1 WO 2004046624 A1 WO2004046624 A1 WO 2004046624A1 KR 0302397 W KR0302397 W KR 0302397W WO 2004046624 A1 WO2004046624 A1 WO 2004046624A1
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WO
WIPO (PCT)
Prior art keywords
ice slurry
heat transfer
aqueous solution
transfer tubes
unit
Prior art date
Application number
PCT/KR2003/002397
Other languages
French (fr)
Inventor
Hyo-Mook Lim
Original Assignee
Hyo-Mook Lim
Priority date (The priority date is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the date listed.)
Filing date
Publication date
Priority claimed from KR10-2002-0081471A external-priority patent/KR100513219B1/en
Application filed by Hyo-Mook Lim filed Critical Hyo-Mook Lim
Priority to AU2003277718A priority Critical patent/AU2003277718A1/en
Publication of WO2004046624A1 publication Critical patent/WO2004046624A1/en

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Classifications

    • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F25—REFRIGERATION OR COOLING; COMBINED HEATING AND REFRIGERATION SYSTEMS; HEAT PUMP SYSTEMS; MANUFACTURE OR STORAGE OF ICE; LIQUEFACTION SOLIDIFICATION OF GASES
    • F25C—PRODUCING, WORKING OR HANDLING ICE
    • F25C1/00—Producing ice
    • F25C1/12—Producing ice by freezing water on cooled surfaces, e.g. to form slabs
    • F25C1/14—Producing ice by freezing water on cooled surfaces, e.g. to form slabs to form thin sheets which are removed by scraping or wedging, e.g. in the form of flakes
    • F25C1/145—Producing ice by freezing water on cooled surfaces, e.g. to form slabs to form thin sheets which are removed by scraping or wedging, e.g. in the form of flakes from the inner walls of cooled bodies
    • F25C1/147—Producing ice by freezing water on cooled surfaces, e.g. to form slabs to form thin sheets which are removed by scraping or wedging, e.g. in the form of flakes from the inner walls of cooled bodies by using augers
    • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F25—REFRIGERATION OR COOLING; COMBINED HEATING AND REFRIGERATION SYSTEMS; HEAT PUMP SYSTEMS; MANUFACTURE OR STORAGE OF ICE; LIQUEFACTION SOLIDIFICATION OF GASES
    • F25C—PRODUCING, WORKING OR HANDLING ICE
    • F25C2500/00—Problems to be solved
    • F25C2500/02—Geometry problems

Definitions

  • the present invention relates to an ice slurry generator, and more specifically, to an ice slurry generator for generating ice slurry that can be used in a dynamic ice storage (thermal energy storage) system as well as a secondary refrigerant.
  • One form of promising energy storage facility is an ice storage system in which electric energy is converted into low temperature thermal energy that in turn is stored in the form of latent thermal energy so that the latent thermal energy can be regenerated.
  • ice slurry for use in a dynamic ice storage system since wide usage is expected in the future as a means (i.e., secondary refrigerant) for thermal energy storage and thermal energy transportation.
  • Active research is going on, on a variety of ice slurry generators capable of economically and reliably generating ice slurry.
  • the ice slurry generators a variety of types have been developed based on different principles.
  • ice slurry generators based on scraped- surface include ice slurry generators based on scraped- surface, supercooled water, direct contact with refrigerant, direct freezing under vacuum, and so on.
  • ice slurry generators based on scraped-surface and supercooled water have become the most popular thus far.
  • the ice slurry generator based on scraped-surface has been considered the most reliable one.
  • the ice slurry generator based on scraped-surface could be classified into two different types, single tube and multi-tube types, in view of their configurations. Recently, intensive developments have been made to the multi-tube type ice slurry generators.
  • the multi-tube type ice slurry generator generally uses a shell & tube vertical heat exchanger, cooled on its outer shell side by an evaporating refrigerant, and scraped on its inner side by rotating blades or orbital rods to prevent any ice crystal deposits on the cooled surface.
  • a whip rod type ice slurry generator e.g., disclosed in Korean Laid-Open Patent Publication No. 2001-0068584
  • a screw scraper type ice slurry generator e.g., disclosed in Korean Patent No.
  • the four technical requirements for multi-tube type ice slurry generator are as follows. First, the ice slurry generator needs to continuously scrape off ice slurry particles from the heat transfer surfaces to prevent them from being deposited and growing thereon. To this end, the degree of supercooling in aqueous solution should be maintained within a predetermined range so that hard ice particles cannot grow on the heat transfer surfaces, thereby enabling fragile ice to be made and allowing the ice to be easily separated. H.N.
  • Fletcher claimed that ice crystals generated when the temperature of supercooled water is above -2.5 ° C become plate-shaped ice with a dendritic crystalline structure and become needle-like or granular ice crystals below - 2.5 ° C (translated by Ki-Won Park, Heat Transfer Phenomenon and Its Application in Cryogenic Environment, Tae-Hoon Publishing, 2001, p.83).
  • a control mechanism is required to maintain mass flow and the degree of supercooling of aqueous solution within predetermined values.
  • it is necessary to use an anti-freezer so that generated ice cannot be agglomerated through recrystallization process.
  • the thermal boundary layer between the heat transfer surface and aqueous solution is kept thin.
  • the thin thermal boundary layer leads to a high heat transfer coefficient and low degree of super cooling in the aqueous solution.
  • the rotating screw continuously scrapes down the mixture of ice slurry and aqueous solution on the heat transfer surface, so that thermal boundary layer is maintained thin.
  • vibration of the structure makes it possible to hold the degree of supercooling low in the aqueous solution in vibration type slurry generator.
  • the generated ice slurry should be transported to the end of the heat transfer tubes and then discharged outside the ice slurry generator.
  • the transportation of the ice slurry to the end of the heat transfer tubes can be easily performed by means of gravity or pumping pressure.
  • the ice slurry flows downward by gravity in the whip rod and vibration type, whereas the ice slurry is transported together with the aqueous solution that is forcibly transported by means of screw rotation to the bottom of the ice slurry generator in the screw scraper type.
  • Care must be taken in the discharge of a mixed solution of ice slurry and an aqueous solution, which are transported from the heat transfer tubes and then collected in a discharge chamber, to the outside of the ice slurry generator.
  • the ice slurry generator When the ice slurry generator is placed above the thermal storage tank, the ice slurry can fall down directly into the thermal storage tank from the heat transfer tubes by gravity.
  • the discharge chamber of the ice slurry generator should be designed to account for the density difference between ice particles and aqueous solution. Since the density of ice slurry is smaller than the aqueous solution, ice particles are separated and float on top of aqueous solution when the flow velocity is below a predetermined value. In this case, there is a high possibility that clogging will occur because of accumulation of ice slurry.
  • the size of the ice slurry generator should be minimized by improving heat transfer efficiency.
  • the reason why the single-tube type ice slurry generator has not become more popular in spite of its operational reliability is that the ice slurry generator is not economic due to its increased size resulting from lack of heat transfer surfaces and limitations on increases in heat transfer efficiency.
  • LMTD logarithmic mean temperature difference
  • the primary refrigerant may depart from a nucleate boiling heat transfer range. Consequently, it is necessary to maximize the heat transfer coefficient on both surfaces for primary refrigerant and aqueous solution. To this end, it is common that dual tubes (see U.S. Patent No. 5,768,894) or machined surface tubes are used on the side of the primary refrigerant. Scraping of thermal boundary layer on the side of the aqueous solution leads to higher heat coefficient. Fourth, power transmission for scraping and flowing upon generation of the ice slurry should be stable and efficient.
  • the whip rod type ice slurry generator has advantages in that power loss is small because power is transmitted by an orbiting mechanism.
  • the screw scraper type provides a relatively simple and stable power transmission through plastic gears.
  • the vibration type has not yet been evaluated fully, but it has potential problems because of its complicated structure. The three potential problems are: First, connections between a diaphragm and a supporting member could be damaged due to vibration energy and the second, a vibration spring could be damaged during operation and the third, the heat transfer surfaces could be worn out.
  • First object is to provide an ice slurry generator, wherein heat transfer efficiency is improved and slurry particles can be easily separated from heat transfer surfaces;
  • Second object is to provide an ice slurry generator, wherein generated ice slurry can be transported and discharged in a stable manner;
  • Third object is to provide an ice slurry generator, wherein power can be stably transmitted;
  • Fourth object is to provide a structure capable of minimizing the size of an ice slurry generator.
  • the ice slurry generator comprises an inflow unit provided with an inlet through which aqueous solution is introduced; a discharge unit provided with an outlet through which the aqueous solution is discharged; a heat exchange unit which is placed between the inflow unit and the discharge unit, and has an inlet and outlet for a refrigerant and heat transfer tubes extending between the inflow unit and discharge unit to define passages through which the aqueous solution passes from the inflow unit to the discharge unit; scrapers which are inserted into the respective heat transfer tubes and each of which has a stem and a spiral blade formed along a periphery of the stem; and a driving device for rotating the scrapers.
  • the scraping blade has two surfaces that face the flow of aqueous solution.
  • the downstream surface of the blade includes a curved surface having a curve in section, and the upstream surface of the blade includes a slanted surface directed to the stem.
  • the curved surface and the slanted surface may meet each other to form an edge.
  • a gap between an inner surface of each heat transfer tube and the blade may be minimized at the edge of the blade.
  • the section of curved surface is a portion of a circle or ellipse.
  • the section of slanted surface may have a straight line.
  • the blade of each scraper may have multiple-start spiral threads.
  • the inflow unit may be disposed below the heat exchange unit, and the discharge unit may be disposed above the heat exchange unit.
  • the discharge unit may be provided with an inclined guiding plate that guides ice slurry to the outlet.
  • the heat exchange unit may include cell partition walls for partitioning the heat transfer tubes into a number of unit cells each of which contains two or more heat transfer tubes, and a refrigerant distributing plate provided with multiple passage holes to uniformly supply the introduced refrigerant to the respective cells.
  • Each cell may contain one of the heat transfer tubes positioned at the center thereof and the remaining heat transfer tubes positioned along a circumference about the center thereof.
  • an ice slurry generator comprises a heat exchange unit which has an inlet and outlet for a refrigerant and a bundle of heat transfer tubes extending vertically to define passages for aqueous solution performing heat exchange with the refrigerant; an inflow unit which is disposed below the heat exchange unit to be connected to the heat transfer tubes and provided with an inlet through which the aqueous solution is introduced; a discharge unit which is disposed above the heat exchange unit to be connected to the heat transfer tubes and provided with an outlet through which the aqueous solution is discharged; scrapers which are inserted into the respective heat transfer tubes and each of which has a stem and a spiral blade formed along a periphery of the stem; and a driving device for rotating the scrapers.
  • the discharge unit may be provided with an inclined guiding plate that guides ice slurry to the outlet.
  • the guiding plate is installed such that one end is attached lower part of the side wall and the other end is attached to the upper part of the side wall where the outlet is provided to guide ice slurry to the outlet.
  • Two guiding plates may be installed in the discharging unit such that one end of both plates are attached to the center of the bottom wall and the other ends are attached to the upper part of side wall to guide ice slurry to the two outlets that are installed on upper part of side wall.
  • a power transmission device chamber in which a power transmission device for driving the scrapers is installed may be placed above the discharge unit, and the power transmission device chamber may be supplied with the aqueous solution from the discharge unit. Filters may be provided between the power transmission device chamber and the discharge unit.
  • an ice slurry generator comprising an inflow unit provided with an inlet through which a aqueous solution is introduced; a discharge unit provided with an outlet through which the aqueous solution is discharged; and a heat exchange unit which is placed between the inflow unit and the discharge unit, and has an inlet and outlet for a refrigerant and heat transfer tubes for defining passages through which the aqueous solution performing heat exchange with the refrigerant passes between the inflow unit and discharge unit.
  • the heat exchange unit includes cell partition walls for partitioning the heat transfer tubes into a number of unit cells each of which contains two or more heat transfer tubes, and a refrigerant distributing plate provided with multiple passage holes to uniformly supply the introduced refrigerant to the respective cells.
  • the ice slurry generator may further comprise scrapers which are inserted into the respective heat transfer tubes and each of which has a stem and a spiral blade formed along a periphery of the stem; and a driving device for rotating the scrapers.
  • Each cell may contain one of the heat transfer tubes positioned at the center thereof and the remaining heat transfer tubes positioned along a circumference about the center thereof.
  • a power transmission device may be provided between the scraper installed in the central heat transfer tube and the scrapers installed in the peripheral heat transfer tubes so that rotational force can be transmitted from the scraper in the center tube to the ones in the peripheral tubes.
  • a method of generating ice slurry in heat transfer tubes containing scrapers each of which has a spiral blade on a periphery thereof comprising the steps of supplying a refrigerant around the heat transfer tubes; and passing a aqueous solution through the heat transfer tubes while rotating the scrapers.
  • a portion of the aqueous solution flows backward through gaps between inner walls of the heat transfer tubes and distal ends of the blades when the aqueous solution moves from an upstream side to a downstream side.
  • the heat transfer tubes may be placed vertically, and the step of passing the aqueous solution may include moving the aqueous solution upward.
  • Fig. 1 is a schematic view showing the configuration of an ice storage cooling system with an ice slurry generator according to an embodiment of the present invention
  • Fig. 2 is a sectional view showing the interior of the ice slurry generator of Fig. i;
  • Fig. 3 is a cross sectional view showing the interior of a heat exchange unit of the ice slurry generator of Fig. 2;
  • Fig. 4 is a cross sectional view showing the interior of another embodiment of the heat exchange unit of the ice slurry generator of Fig. 2;
  • Fig. 5 is a sectional view showing another embodiment of a discharge chamber of the ice slurry generator of Fig. 2;
  • Fig. 6 is a view showing the shape of a scraper of Fig. 2;
  • Fig. 7 is a partially enlarged, longitudinal sectional view of blades of the scraper of Fig. 6 on a large scale
  • Fig. 8 is a cross sectional view of the scraper of Fig. 6.
  • Fig. 1 is a schematic view showing the configuration of an ice storage cooling system with an ice slurry generator according to an embodiment of the present invention.
  • the ice storage cooling system includes a cooling tower 2, a compressor 1, an ice slurry generator 10, a thermal storage tank 5, and a heat exchanger 9.
  • the cooling tower 2 cools down cooling water, which is returned after it has been used in the compressor 1, to be reused.
  • the cooling water that has been thus cooled is again supplied to the compressor 1 by means of a pump 4.
  • the compressor 1 compresses a gaseous refrigerant, which has been returned from the ice slurry generator 10, at high temperature and pressure.
  • the gaseous refrigerant compressed at high temperature and pressure is condensed by the cooling water supplied from the cooling tower 2 and then discharged from the compressor 1.
  • the liquid refrigerant discharged from the compressor 1 is introduced into the ice slurry generator 10 through an expansion valve 3.
  • the liquid refrigerant introduced into the ice slurry generator 10 evaporates and then is returned back to the compressor 1.
  • the ice slurry generator 10 performs the phase change of a portion of an introduced aqueous solution to ice slurry by using the refrigerant and discharges the ice slurry.
  • the aqueous solution discharged from the ice slurry generator 10 is stored in the thermal storage tank 5.
  • the aqueous solution stored in the thermal storage tank 5 is transported to the heat exchanger 9 by a circulation pump 6.
  • the flow rate of the aqueous solution is controlled by a three-way valve 7 for adjusting the flow rate depending on the load temperature condition and a portion of the aqueous solution passes through a bypass line 7a without passing through the heat exchanger 9.
  • a portion or almost all of the joined aqueous solution is introduced into a lower portion of the ice slurry generator 10 to reduce the temperature of the aqueous solution or be subjected to the partial phase change thereof to ice slurry, and is then returned to the thermal storage tank 5.
  • the flow rate of the aqueous solution may be controlled by adjusting revolutions of the pump using an inverter circuit.
  • the aqueous solution when introduced into the lower portion of the ice slurry generator 10, it passes through a foreign material-removing device 11 such as a filter into the ice slurry generator 10. A portion of the aqueous solution flows into a power transmission device chamber 82 to remove heat generated due to the rotation of gears and then joins the other portion of the aqueous solution discharged from an outlet 62 (see Fig. 2).
  • the aqueous solution that is being returned to the thermal storage tank 5 flows into an upper portion of the thermal storage tank 5, is cooled while passing through an ice slurry layer floating at the upper portion of the thermal storage tank 5, and then flows to a lower portion of the thermal storage tank to be continuously introduced into the pump 6, thereby forming a cooling cycle.
  • Figs. 2 to 8 are drawings of the ice slurry generator 10 shown in Fig. 1.
  • the ice slurry generator 10 includes a heat exchange unit 20, an inflow unit 40, a discharge unit 60 and a driving unit 80.
  • the inflow unit 40 placed below the heat exchange unit 20, and the discharge unit 60 placed above the heat exchange unit 40.
  • the driving unit 80 is positioned above the discharge unit 60.
  • the heat exchange unit 20 includes a cylindrical shell 12.
  • the cylindrical shell 12 includes a sidewall and upper and lower supporting plates 22 and 24 which close the top and bottom opening of the shell 12 and support heat transfer tubes 15 to be described later.
  • a heat exchange chamber 18 is defined by the sidewall and the upper and lower supporting plates 22 and 24.
  • the heat exchange chamber 18 is provided with a bundle of vertical heat transfer tubes 15, upper and lower refrigerant distribution plates 14 and 17 and cell partition walls 30.
  • a refrigerant inlet 99 through which the liquid refrigerant flows in is provided at the bottom of the shell 12 (more specifically, between the lower support plate 24 and the lower refrigerant distributing plate 16).
  • an inlet, an auxiliary inlet and outlet for a refrigerant returned from a low-pressure liquid separator may be further provided.
  • a refrigerant outlet 98 through which a gaseous refrigerant is discharged and which is connected to the compressor via the low-pressure separator (not shown) is provided at the top of the shell 12 (more specifically, between the upper support plate 22 and the upper refrigerant distributing plate 14).
  • the heat transfer tubes 15 are made of metal with superior thermal conductivity and have circular cross sections. Upper and lower portions of the heat transfer tubes are coupled to and supported by the upper and lower support plates 22 and 24, respectively, by means of a tube expansion process or a coupling method such as welding.
  • the aqueous solution inlet 40 is connected to the outlet 60 through the heat transfer tubes 15.
  • a front-curved and rear-slanted scraper 16 or 16a to be described later is inserted into and accommodated in each of the heat transfer tubes 15. Ice particles separated from the surfaces of the heat transfer tubes and the aqueous solution are transported from an inflow chamber 43 to a discharge chamber 61 through the heat transfer tubes 15 by means of the rotating scrapers 16 and 16a.
  • the upper and lower refrigerant distributing plates 14 and 17 are provided to be slightly spaced apart from the upper and lower support plates 22 and 24, respectively.
  • the upper and lower refrigerant distributing plates 14 and 17 are provided with multiple passage holes 141 and 171.
  • the refrigerant is uniformly distributed and supplied to respective cells to be described later through the passage holes 141 and 171 of the upper and lower refrigerant distributing plates 14 and 17.
  • the multiple heat transfer tubes 15 are partitioned into several adjoining cells 31 having the same shape (regular hexagon in this embodiment) in cross section by means of the cell partition walls 30 extending between the upper and lower refrigerant distributing plates 14 and 17, as well shown in Fig. 3.
  • Each cell 31 accommodates multiple heat transfer tubes (seven tubes in this embodiment).
  • the heat transfer tubes are arranged such that one of the heat transfer tubes is placed at the center of the cell and the remaining heat transfer tubes are placed around the periphery of the centered heat transfer tube. Referring to Fig.
  • the multiple passage holes 141 and 171 of the upper and lower refrigerant distributing plates 14 and 17 are arranged such that the same number of passages holes (three passage holes in this embodiment) exists in every cell 31. Therefore, refrigerant is uniformly distributed and supplied to the respective cells 31. With such a configuration, it improves overall heat transfer efficiency by eliminating a refrigerant biasing problem that is a disadvantage in a conventional vertical heat exchanger.
  • seven unit cells 31 are provided within the shell 12.
  • the number of cells 31 can be varied. For example, nineteen cells can be formed as shown in Fig. 4. Further, although it has been described that each cell takes the shape of a regular polygon, the cell can also be differently shaped in addition to a regular polygon.
  • the aqueous solution inflow unit 40 is placed below the heat exchange unit 20.
  • the aqueous solution inflow unit 40 has the inflow chamber 43 defined by the lower supporting plate 24 and a casing 41 coupled thereto.
  • the inflow chamber 43 is connected to the heat transfer tubes 15 that are attached to the lower supporting plate 24.
  • a lower portion of the casing 41 is provided with an inlet 42 through which the aqueous solution is introduced thereinto.
  • An aqueous solution distributing plate 44 is horizontally placed above the inlet 42 within the inflow chamber 43.
  • the plate 44 is provided with multiple passage holes 441 to enable the aqueous solution to flow uniformly. It is preferred that the casing 41 be detachably coupled to the lower supporting plate 24.
  • a cylindrical upper casing 50 is coupled to the top of the upper support plate 22, and a top plate 79 is coupled to the top of the upper casing 50.
  • a horizontal supporting plate 68 is provided in an inner space defined by the upper casing 50, the upper supporting plate 22 and the top plate 79.
  • the driving unit 80 and the discharge unit 60 are disposed above and below the support plate 68, respectively.
  • the discharge unit 60 is provided with an inclined guiding plate 64 for diagonally partitioning the space.
  • the discharge chamber 61 is a space below the inclined plate 64.
  • the outlet 61 is provided at an upper portion of a sidewall of the discharge chamber 61, i.e. a portion adjacent to an uppermost portion of the inclined plate 64.
  • the aqueous solution including ice slurry transported to the discharge chamber 61 through the heat transfer tubes 15 is guided by the inclined plate 64 and discharged through the outlet 62.
  • the inclined guiding plate 64 is provided with holes through which the scrapers 16 extend to the driving unit 80. There are gaps or apertures in the inclined guiding plate 64 so that a portion of the aqueous solution can flow to above the inclined guiding plate 64.
  • the aqueous solution fills in the power transmission device chamber 82 through passages 681 provided in the supporting plate 68 so as to function as lubricant and coolant of a power transmission device.
  • FIG. 5 shows another embodiment of the discharge unit.
  • the two inclined guiding plates 64a are configured such that those incline up from the center of the discharge unit to the side wall of the discharge chamber.
  • the discharge chamber 61a may be provided with two or more outlets 62a. With such a structure, the height of the discharge chamber can be reduced.
  • the driving unit 80 is provided above the discharge unit 60.
  • the driving unit 80 includes a driving device 90 provided on the top plate 79, and a power transmission device for delivering power from a driving device 90.
  • the driving unit 80 includes the power transmission device chamber 82 between the top plate 79 and the support plate 68 to accommodate the power transmission device.
  • the driving device 90 includes a rotation driving motor and a reduction device for adjusting the number of revolutions.
  • a rotational shaft 92 of the driving device 90 is inserted into the power transmission chamber 82 while being maintained in a sealed state by means of a shaft-sealing member (also called a "shaft sealing") 91.
  • a number of gears are provided within the power transmission device chamber 82 to construct the power transmission device for transmitting a rotational force.
  • a primary driving gear 95 is mounted on the rotational shaft 92 of the driving device 90.
  • a primary driven gear 70 is mounted on a rotational shaft of the scraper 16a positioned at the center of each cell 31 of the heat-exchange chamber 18. The primary driven gear 70 is engaged with the primary driving gear 95 to receive the rotational force.
  • a secondary driving gear 72 is also mounted on the rotational shaft of the scraper 16a provided with the primary driven gear 70.
  • a secondary driven gear 74 is mounted on a rotational shaft of each of the scrapers 16 surrounding the scraper 16a positioned at the center of each cell 31. The secondary driven gear 74 is engaged with the secondary driving gear 72 to receive the rotational force.
  • the respective scrapers 16 and 16a are rotated at similar speeds by the driving device 90.
  • the diameter of the secondary driving gear is slightly larger than that of the secondary driven gear. Therefore, the peripheral scrapers 16 are rotated slightly faster than the central scraper 16a. This is to prevent unnecessary interference among the gears for the scrapers.
  • the spiral directions of blades of the scrapers are also opposite to each other. Journaling devices such as ball bearings are installed in the support plate
  • an outlet 78 is provided on the side surface of the power transmission device chamber (also referred to as "gear chamber") 82.
  • the aqueous solution for cooling and lubrication that has been introduced through the passages 681 of the support plate 68 is discharged to the outside through the outlet 78.
  • the exiting aqueous solution joins the aqueous solution discharged from the discharge chamber 61.
  • the aqueous solution for cooling and lubrication the aqueous solution existing above the inclined guiding plate 64 is introduced into the power transmission device chamber 82 through the passages 681 provided in the support plate 68.
  • the driving unit is disposed at the uppermost portion of the ice slurry generator 10 in the present invention, the present invention is limited thereto. It can be understood by those skilled in the art that the driving unit can be alternatively disposed at the lowermost portion of the ice slurry generator 10.
  • each scraper 16 includes a stem 161 corresponding to a central shaft, and a blade 162 formed along the periphery of the stem 161 at a predetermined angle.
  • the scraper 16 can vary according to the size and structure of the ice slurry generator, it is made of plastic resin (for example, PE, POM, etc.) and may also be made of any materials having cold resistance, water resistance and rigidity. It is preferred that a metal insert be inserted into the stem 161 to reinforce the rigidity and straightness thereof.
  • an upper surface (a downstream surface with respect to the flow direction of the aqueous solution) of the blade 162 includes a convex surface with a predetermined radius of curvature R in section, and a lower surface (an upstream surface with respect to the flow direction of the aqueous solution) of the blade 162 includes a slanted surface that is inclined at a predetermined angle ⁇ and preferably, constitutes a spiral surface which is linear in section (this configuration is herein referred to as a "front-curved and rear- slanted" configuration).
  • the radius of curvature R be generally 6 to 15 mm
  • the angle ⁇ be generally 10 to 20 degrees.
  • a distal end of the blade 162 is established in such a manner that the curve directly joins the line. Since the outer diameter of the distal end is maintained constant throughout the blade, a gap g between the distal end and an inner surface of the relevant heat transfer tube 15 is constant.
  • the blade 162 is a multiple-start thread blade. In the embodiment shown in Figs. 2, 6 and 7, the blade is a triple-start thread blade. Therefore, since the heat transfer surface is scraped as many times as corresponds to the number of starts (three times in case of the triple-start thread blade) every one revolution of the scraper, the scraper can be operated at a low speed.
  • the aqueous solution is introduced from the inflow chamber 40 into spaces defined by the inner surface of the heat transfer tube, the stem 161 and the surfaces of the blade 162 as the scraper 16 is rotated, so that it can flow in the heat transfer tube.
  • the aqueous solution flows through the small gap g between the distal end of the blade 162 and the heat transfer tube 15 in a direction designated by an arrow as shown in Fig. 8 and sweeps away a film formed at the gap g.
  • the aqueous solution is mixed up while passing through the gap g, thereby enhancing heat transfer and lowering the degree of supercooling in aqueous solution. Consequently, ice slurry can be generated in stable manner.
  • FIG. 8 This state is well shown in Fig. 8.
  • the structure of the front-curved and rear-slanted scraper according to the present invention enables high heat transfer efficiency that is an advantage of the conventional whip rod type ice slurry generator, and stable transportation of ice slurry and low operational noises that are advantages of a scraper type ice slurry generator.
  • the operation of the ice slurry generator will be described in detail with reference to Figs. 2 and 3.
  • the liquid refrigerant is introduced into the heat exchange chamber 18 through the refrigerant inlet 99 provided at a lower portion of the heat-exchange chamber.
  • the refrigerant introduced into the heat-exchange chamber 18 is uniformly distributed among and supplied to the respective unit cells 31 through the passage holes 171 of the lower refrigerant distributing plate 17.
  • the liquid refrigerant supplied to the respective cells 31 flows upward, evaporates while taking heat away from the aqueous solution within the heat transfer tubes 15, and then escapes from the upper portion of the heat- exchange chamber 18 through the passage holes 141 of the upper refrigerant distributing plate 14.
  • the gaseous refrigerant above the heat exchange chamber 18 is discharged toward the compressor (designated by reference numeral 1 in Fig. 1) through the refrigerant outlet 98.
  • the aqueous solution is introduced into the inflow chamber 43 through the inlet 42 of the inflow unit 40 provided at the lower portion of the ice slurry generator 10.
  • the aqueous solution introduced into the inflow chamber 43 uniformly flows upward through the passage holes 441 on the aqueous solution distributing plate 44.
  • the aqueous solution is sucked into the heat transfer tubes 15 by negative pumping pressure induced by the rotating scrapers 16.
  • heat in the aqueous solution is taken away by the refrigerant in the heat-exchange chamber 18 so that a portion of the aqueous solution can be subjected to phase change and thus become ice slurry.
  • the aqueous solution containing the ice slurry flows into the discharge chamber 61 through the heat transfer tubes 15, is discharged through the outlet 62, and finally transported to and stored in the thermal storage tank (designated by reference numeral 5 in Fig. 1).
  • a portion of the aqueous solution in the discharge chamber 61 flows into the upper space of guiding plate 64 through the holes on it.
  • the aqueous solution then enters the power transmission device chamber 82 through the passages 681 of the supporting plate 68, performs cooling and lubricating functions and exits through the outlet 78.
  • the exiting aqueous solution joins the aqueous solution discharged from the discharge chamber 61.
  • the filters are mounted in the passages 681 of the supporting plate 68 and the outlet 78 of the power transmission device chamber 82 to filter out foreign materials that are contained in the aqueous solution and may affect the operations of the gears.
  • the present design leads to high heat transfer efficiency which is an advantage of the existing whip rod type ice slurry generator, and stable transportation of ice slurry and reduced noise that are advantages of the existing scraper type ice slurry generator.
  • the flow of the refrigerant is uniform, overall high heat transfer efficiency is improved.
  • the aqueous solution flows upward; thus, it significantly reduces problems of accumulation and clogging caused by separation of ice particle and aqueous solution resulting from density difference, thereby ensuring more stable operation.
  • the driving unit provides improved durability and more reliable load distribution, prevention of introduction of foreign materials, and the like.

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  • Engineering & Computer Science (AREA)
  • Physics & Mathematics (AREA)
  • Mechanical Engineering (AREA)
  • Thermal Sciences (AREA)
  • General Engineering & Computer Science (AREA)
  • Heat-Exchange Devices With Radiators And Conduit Assemblies (AREA)

Abstract

An ice slurry generator includes a plurality of heat transfer tubes and a plurality of screw scrapers, each of which is contained in each tube. Each scraper has a stem and a spiral blade attached to the stem. The blade has an upstream side and a downstream side. The downstream side has a curved surface and the upstream side has a linear surface.

Description

ICE SLURRY GENERATOR
Technical Field
The present invention relates to an ice slurry generator, and more specifically, to an ice slurry generator for generating ice slurry that can be used in a dynamic ice storage (thermal energy storage) system as well as a secondary refrigerant.
Background Art
One form of promising energy storage facility is an ice storage system in which electric energy is converted into low temperature thermal energy that in turn is stored in the form of latent thermal energy so that the latent thermal energy can be regenerated. Particularly, a great deal of attention is on ice slurry for use in a dynamic ice storage system since wide usage is expected in the future as a means (i.e., secondary refrigerant) for thermal energy storage and thermal energy transportation. Active research is going on, on a variety of ice slurry generators capable of economically and reliably generating ice slurry. As for the ice slurry generators, a variety of types have been developed based on different principles. These include ice slurry generators based on scraped- surface, supercooled water, direct contact with refrigerant, direct freezing under vacuum, and so on. Among them, ice slurry generators based on scraped-surface and supercooled water have become the most popular thus far. Heretofore, the ice slurry generator based on scraped-surface has been considered the most reliable one. The ice slurry generator based on scraped-surface could be classified into two different types, single tube and multi-tube types, in view of their configurations. Recently, intensive developments have been made to the multi-tube type ice slurry generators.
The multi-tube type ice slurry generator generally uses a shell & tube vertical heat exchanger, cooled on its outer shell side by an evaporating refrigerant, and scraped on its inner side by rotating blades or orbital rods to prevent any ice crystal deposits on the cooled surface. As for typical multi-tube type ice slurry generators, there have been developed a whip rod type ice slurry generator (e.g., disclosed in Korean Laid-Open Patent Publication No. 2001-0068584) using a whip rod that orbits along an inner wall of each heat transfer tube therein, a screw scraper type ice slurry generator (e.g., disclosed in Korean Patent No. 10-0296653) in which a spiral scraper made of plastic material is rotated in the interior of each heat transfer tube to generate ice slurry, a vibration type ice slurry generator (e.g., Korean Utility Model Registration No. 20- 0240787) using the movement of springs due to vibration energy with a vibration spring apparatus, and the like. However, although the developed ice slurry generators are most reliable among the commercially available slurry generators, they have a common drawback that the power transmission mechanism for the scraper is complicated and suffers from occasional failures. Further, clogging of tube by ice particles because of deposition in the discharging process limits the popularity of the ice slurry generators.
The four technical requirements for multi-tube type ice slurry generator are as follows. First, the ice slurry generator needs to continuously scrape off ice slurry particles from the heat transfer surfaces to prevent them from being deposited and growing thereon. To this end, the degree of supercooling in aqueous solution should be maintained within a predetermined range so that hard ice particles cannot grow on the heat transfer surfaces, thereby enabling fragile ice to be made and allowing the ice to be easily separated. H.N. Fletcher claimed that ice crystals generated when the temperature of supercooled water is above -2.5 °C become plate-shaped ice with a dendritic crystalline structure and become needle-like or granular ice crystals below - 2.5 °C (translated by Ki-Won Park, Heat Transfer Phenomenon and Its Application in Cryogenic Environment, Tae-Hoon Publishing, 2001, p.83). Thus, a control mechanism is required to maintain mass flow and the degree of supercooling of aqueous solution within predetermined values. Further, it is necessary to use an anti-freezer so that generated ice cannot be agglomerated through recrystallization process. In the whip rod type ice slurry generator, metal rods orbit at high speed so that the thermal boundary layer between the heat transfer surface and aqueous solution is kept thin. The thin thermal boundary layer leads to a high heat transfer coefficient and low degree of super cooling in the aqueous solution. Even in the screw scraper type, the rotating screw continuously scrapes down the mixture of ice slurry and aqueous solution on the heat transfer surface, so that thermal boundary layer is maintained thin. Similarly, vibration of the structure makes it possible to hold the degree of supercooling low in the aqueous solution in vibration type slurry generator. Second, the generated ice slurry should be transported to the end of the heat transfer tubes and then discharged outside the ice slurry generator. The transportation of the ice slurry to the end of the heat transfer tubes can be easily performed by means of gravity or pumping pressure. The ice slurry flows downward by gravity in the whip rod and vibration type, whereas the ice slurry is transported together with the aqueous solution that is forcibly transported by means of screw rotation to the bottom of the ice slurry generator in the screw scraper type. Care must be taken in the discharge of a mixed solution of ice slurry and an aqueous solution, which are transported from the heat transfer tubes and then collected in a discharge chamber, to the outside of the ice slurry generator. When the ice slurry generator is placed above the thermal storage tank, the ice slurry can fall down directly into the thermal storage tank from the heat transfer tubes by gravity. However, when the installation space is limited, ice slurry in the discharge chamber should be transported by pump pressure to the storage tank. In this case, the discharge chamber of the ice slurry generator should be designed to account for the density difference between ice particles and aqueous solution. Since the density of ice slurry is smaller than the aqueous solution, ice particles are separated and float on top of aqueous solution when the flow velocity is below a predetermined value. In this case, there is a high possibility that clogging will occur because of accumulation of ice slurry.
Third, the size of the ice slurry generator should be minimized by improving heat transfer efficiency. The reason why the single-tube type ice slurry generator has not become more popular in spite of its operational reliability is that the ice slurry generator is not economic due to its increased size resulting from lack of heat transfer surfaces and limitations on increases in heat transfer efficiency. In the ice slurry generator, it is not feasible to increase the logarithmic mean temperature difference (temperature gradient, LMTD) between aqueous solution and a primary refrigerant over a predetermined range, contrary to a general heat exchanger. If the LMTD departs from predetermined range, operational stability would be deteriorated due to high degree supercooling in the aqueous solution. Further, the primary refrigerant may depart from a nucleate boiling heat transfer range. Consequently, it is necessary to maximize the heat transfer coefficient on both surfaces for primary refrigerant and aqueous solution. To this end, it is common that dual tubes (see U.S. Patent No. 5,768,894) or machined surface tubes are used on the side of the primary refrigerant. Scraping of thermal boundary layer on the side of the aqueous solution leads to higher heat coefficient. Fourth, power transmission for scraping and flowing upon generation of the ice slurry should be stable and efficient. The whip rod type ice slurry generator has advantages in that power loss is small because power is transmitted by an orbiting mechanism. In addition, it can run even though ice crystals grow on the heat transfer surfaces and this would prevent further growth of ice crystals on the surfaces. However, the transmission load is concentrated on the junctions of the orbiting structure and it is more likely to fail because of its complicated mechanical structure. The screw scraper type provides a relatively simple and stable power transmission through plastic gears. However, it has shortcomings that since teeth of the gears are exposed directly to the aqueous solution, part or all of the ice slurry generator may become frozen if the teeth are damaged due to the introduction of foreign materials. The vibration type has not yet been evaluated fully, but it has potential problems because of its complicated structure. The three potential problems are: First, connections between a diaphragm and a supporting member could be damaged due to vibration energy and the second, a vibration spring could be damaged during operation and the third, the heat transfer surfaces could be worn out.
Summary of the Invention
There are four specific objects for the present inventions: First object is to provide an ice slurry generator, wherein heat transfer efficiency is improved and slurry particles can be easily separated from heat transfer surfaces;
Second object is to provide an ice slurry generator, wherein generated ice slurry can be transported and discharged in a stable manner; Third object is to provide an ice slurry generator, wherein power can be stably transmitted;
Fourth object is to provide a structure capable of minimizing the size of an ice slurry generator.
According to an aspect of the present invention, the ice slurry generator comprises an inflow unit provided with an inlet through which aqueous solution is introduced; a discharge unit provided with an outlet through which the aqueous solution is discharged; a heat exchange unit which is placed between the inflow unit and the discharge unit, and has an inlet and outlet for a refrigerant and heat transfer tubes extending between the inflow unit and discharge unit to define passages through which the aqueous solution passes from the inflow unit to the discharge unit; scrapers which are inserted into the respective heat transfer tubes and each of which has a stem and a spiral blade formed along a periphery of the stem; and a driving device for rotating the scrapers. The scraping blade has two surfaces that face the flow of aqueous solution. The downstream surface of the blade includes a curved surface having a curve in section, and the upstream surface of the blade includes a slanted surface directed to the stem.
In an embodiment, the curved surface and the slanted surface may meet each other to form an edge. A gap between an inner surface of each heat transfer tube and the blade may be minimized at the edge of the blade. The section of curved surface is a portion of a circle or ellipse. The section of slanted surface may have a straight line. The blade of each scraper may have multiple-start spiral threads.
In an embodiment, the inflow unit may be disposed below the heat exchange unit, and the discharge unit may be disposed above the heat exchange unit. The discharge unit may be provided with an inclined guiding plate that guides ice slurry to the outlet. In an embodiment, the heat exchange unit may include cell partition walls for partitioning the heat transfer tubes into a number of unit cells each of which contains two or more heat transfer tubes, and a refrigerant distributing plate provided with multiple passage holes to uniformly supply the introduced refrigerant to the respective cells. Each cell may contain one of the heat transfer tubes positioned at the center thereof and the remaining heat transfer tubes positioned along a circumference about the center thereof. A power transmission device may be provided between the scraper installed in the central heat transfer tube and the scrapers installed in the peripheral heat transfer tubes so that a rotational force can be transmitted from the scraper in center tube to the ones in peripheral tubes. According to another aspect of the present invention, an ice slurry generator comprises a heat exchange unit which has an inlet and outlet for a refrigerant and a bundle of heat transfer tubes extending vertically to define passages for aqueous solution performing heat exchange with the refrigerant; an inflow unit which is disposed below the heat exchange unit to be connected to the heat transfer tubes and provided with an inlet through which the aqueous solution is introduced; a discharge unit which is disposed above the heat exchange unit to be connected to the heat transfer tubes and provided with an outlet through which the aqueous solution is discharged; scrapers which are inserted into the respective heat transfer tubes and each of which has a stem and a spiral blade formed along a periphery of the stem; and a driving device for rotating the scrapers.
In an embodiment, the discharge unit may be provided with an inclined guiding plate that guides ice slurry to the outlet. The guiding plate is installed such that one end is attached lower part of the side wall and the other end is attached to the upper part of the side wall where the outlet is provided to guide ice slurry to the outlet. Two guiding plates may be installed in the discharging unit such that one end of both plates are attached to the center of the bottom wall and the other ends are attached to the upper part of side wall to guide ice slurry to the two outlets that are installed on upper part of side wall. A power transmission device chamber in which a power transmission device for driving the scrapers is installed may be placed above the discharge unit, and the power transmission device chamber may be supplied with the aqueous solution from the discharge unit. Filters may be provided between the power transmission device chamber and the discharge unit.
According to the further aspect of the present invention, there is provided an ice slurry generator comprising an inflow unit provided with an inlet through which a aqueous solution is introduced; a discharge unit provided with an outlet through which the aqueous solution is discharged; and a heat exchange unit which is placed between the inflow unit and the discharge unit, and has an inlet and outlet for a refrigerant and heat transfer tubes for defining passages through which the aqueous solution performing heat exchange with the refrigerant passes between the inflow unit and discharge unit. The heat exchange unit includes cell partition walls for partitioning the heat transfer tubes into a number of unit cells each of which contains two or more heat transfer tubes, and a refrigerant distributing plate provided with multiple passage holes to uniformly supply the introduced refrigerant to the respective cells.
In an embodiment, the ice slurry generator may further comprise scrapers which are inserted into the respective heat transfer tubes and each of which has a stem and a spiral blade formed along a periphery of the stem; and a driving device for rotating the scrapers. Each cell may contain one of the heat transfer tubes positioned at the center thereof and the remaining heat transfer tubes positioned along a circumference about the center thereof. A power transmission device may be provided between the scraper installed in the central heat transfer tube and the scrapers installed in the peripheral heat transfer tubes so that rotational force can be transmitted from the scraper in the center tube to the ones in the peripheral tubes.
According to the further aspect of the present invention, there is provided a method of generating ice slurry in heat transfer tubes containing scrapers each of which has a spiral blade on a periphery thereof, comprising the steps of supplying a refrigerant around the heat transfer tubes; and passing a aqueous solution through the heat transfer tubes while rotating the scrapers. In the step of passing the aqueous solution, a portion of the aqueous solution flows backward through gaps between inner walls of the heat transfer tubes and distal ends of the blades when the aqueous solution moves from an upstream side to a downstream side. In an embodiment, the heat transfer tubes may be placed vertically, and the step of passing the aqueous solution may include moving the aqueous solution upward.
Brief Description of the Drawings
For better understanding of the objects and features of the present invention by those skilled in the art, preferred embodiments of the present invention will be described with reference to the accompanying drawings in which:
Fig. 1 is a schematic view showing the configuration of an ice storage cooling system with an ice slurry generator according to an embodiment of the present invention;
Fig. 2 is a sectional view showing the interior of the ice slurry generator of Fig. i;
Fig. 3 is a cross sectional view showing the interior of a heat exchange unit of the ice slurry generator of Fig. 2;
Fig. 4 is a cross sectional view showing the interior of another embodiment of the heat exchange unit of the ice slurry generator of Fig. 2;
Fig. 5 is a sectional view showing another embodiment of a discharge chamber of the ice slurry generator of Fig. 2; Fig. 6 is a view showing the shape of a scraper of Fig. 2;
Fig. 7 is a partially enlarged, longitudinal sectional view of blades of the scraper of Fig. 6 on a large scale; and
Fig. 8 is a cross sectional view of the scraper of Fig. 6.
Detailed Description of the Embodiments
Hereinafter, embodiments of the present invention will be described in detail with reference to the accompanying drawings. Fig. 1 is a schematic view showing the configuration of an ice storage cooling system with an ice slurry generator according to an embodiment of the present invention. Referring to Fig. 1, the ice storage cooling system includes a cooling tower 2, a compressor 1, an ice slurry generator 10, a thermal storage tank 5, and a heat exchanger 9. The cooling tower 2 cools down cooling water, which is returned after it has been used in the compressor 1, to be reused. The cooling water that has been thus cooled is again supplied to the compressor 1 by means of a pump 4. The compressor 1 compresses a gaseous refrigerant, which has been returned from the ice slurry generator 10, at high temperature and pressure. The gaseous refrigerant compressed at high temperature and pressure is condensed by the cooling water supplied from the cooling tower 2 and then discharged from the compressor 1. The liquid refrigerant discharged from the compressor 1 is introduced into the ice slurry generator 10 through an expansion valve 3. The liquid refrigerant introduced into the ice slurry generator 10 evaporates and then is returned back to the compressor 1.
The ice slurry generator 10 performs the phase change of a portion of an introduced aqueous solution to ice slurry by using the refrigerant and discharges the ice slurry. The aqueous solution discharged from the ice slurry generator 10 is stored in the thermal storage tank 5. The aqueous solution stored in the thermal storage tank 5 is transported to the heat exchanger 9 by a circulation pump 6. The flow rate of the aqueous solution is controlled by a three-way valve 7 for adjusting the flow rate depending on the load temperature condition and a portion of the aqueous solution passes through a bypass line 7a without passing through the heat exchanger 9. The portion of aqueous solution that has passed through the heat exchanger 9 and the other portion thereof that has passed through the bypass line 7a join each other through the three-way valve 7 and are then returned to the thermal storage tank. In some cases, a portion or almost all of the joined aqueous solution is introduced into a lower portion of the ice slurry generator 10 to reduce the temperature of the aqueous solution or be subjected to the partial phase change thereof to ice slurry, and is then returned to the thermal storage tank 5. The flow rate of the aqueous solution may be controlled by adjusting revolutions of the pump using an inverter circuit.
Meanwhile, when the aqueous solution is introduced into the lower portion of the ice slurry generator 10, it passes through a foreign material-removing device 11 such as a filter into the ice slurry generator 10. A portion of the aqueous solution flows into a power transmission device chamber 82 to remove heat generated due to the rotation of gears and then joins the other portion of the aqueous solution discharged from an outlet 62 (see Fig. 2). The aqueous solution that is being returned to the thermal storage tank 5 flows into an upper portion of the thermal storage tank 5, is cooled while passing through an ice slurry layer floating at the upper portion of the thermal storage tank 5, and then flows to a lower portion of the thermal storage tank to be continuously introduced into the pump 6, thereby forming a cooling cycle.
Figs. 2 to 8 are drawings of the ice slurry generator 10 shown in Fig. 1. Referring to Figs. 2 and 3, the ice slurry generator 10 includes a heat exchange unit 20, an inflow unit 40, a discharge unit 60 and a driving unit 80. The inflow unit 40 placed below the heat exchange unit 20, and the discharge unit 60 placed above the heat exchange unit 40. The driving unit 80 is positioned above the discharge unit 60.
The heat exchange unit 20 includes a cylindrical shell 12. The cylindrical shell 12 includes a sidewall and upper and lower supporting plates 22 and 24 which close the top and bottom opening of the shell 12 and support heat transfer tubes 15 to be described later. A heat exchange chamber 18 is defined by the sidewall and the upper and lower supporting plates 22 and 24. The heat exchange chamber 18 is provided with a bundle of vertical heat transfer tubes 15, upper and lower refrigerant distribution plates 14 and 17 and cell partition walls 30. A refrigerant inlet 99 through which the liquid refrigerant flows in is provided at the bottom of the shell 12 (more specifically, between the lower support plate 24 and the lower refrigerant distributing plate 16). Although not shown in this drawing, an inlet, an auxiliary inlet and outlet for a refrigerant returned from a low-pressure liquid separator may be further provided. A refrigerant outlet 98 through which a gaseous refrigerant is discharged and which is connected to the compressor via the low-pressure separator (not shown) is provided at the top of the shell 12 (more specifically, between the upper support plate 22 and the upper refrigerant distributing plate 14).
The heat transfer tubes 15 are made of metal with superior thermal conductivity and have circular cross sections. Upper and lower portions of the heat transfer tubes are coupled to and supported by the upper and lower support plates 22 and 24, respectively, by means of a tube expansion process or a coupling method such as welding. The aqueous solution inlet 40 is connected to the outlet 60 through the heat transfer tubes 15. A front-curved and rear-slanted scraper 16 or 16a to be described later is inserted into and accommodated in each of the heat transfer tubes 15. Ice particles separated from the surfaces of the heat transfer tubes and the aqueous solution are transported from an inflow chamber 43 to a discharge chamber 61 through the heat transfer tubes 15 by means of the rotating scrapers 16 and 16a.
The upper and lower refrigerant distributing plates 14 and 17 are provided to be slightly spaced apart from the upper and lower support plates 22 and 24, respectively. The upper and lower refrigerant distributing plates 14 and 17 are provided with multiple passage holes 141 and 171. The refrigerant is uniformly distributed and supplied to respective cells to be described later through the passage holes 141 and 171 of the upper and lower refrigerant distributing plates 14 and 17.
Although not shown in Fig. 2, the multiple heat transfer tubes 15 are partitioned into several adjoining cells 31 having the same shape (regular hexagon in this embodiment) in cross section by means of the cell partition walls 30 extending between the upper and lower refrigerant distributing plates 14 and 17, as well shown in Fig. 3. Each cell 31 accommodates multiple heat transfer tubes (seven tubes in this embodiment). At this time, the heat transfer tubes are arranged such that one of the heat transfer tubes is placed at the center of the cell and the remaining heat transfer tubes are placed around the periphery of the centered heat transfer tube. Referring to Fig. 3, the multiple passage holes 141 and 171 of the upper and lower refrigerant distributing plates 14 and 17 are arranged such that the same number of passages holes (three passage holes in this embodiment) exists in every cell 31. Therefore, refrigerant is uniformly distributed and supplied to the respective cells 31. With such a configuration, it improves overall heat transfer efficiency by eliminating a refrigerant biasing problem that is a disadvantage in a conventional vertical heat exchanger. In the embodiment, seven unit cells 31 are provided within the shell 12. However, the present invention is not limited thereto. The number of cells 31 can be varied. For example, nineteen cells can be formed as shown in Fig. 4. Further, although it has been described that each cell takes the shape of a regular polygon, the cell can also be differently shaped in addition to a regular polygon.
Referring again to Fig. 2, the aqueous solution inflow unit 40 is placed below the heat exchange unit 20. The aqueous solution inflow unit 40 has the inflow chamber 43 defined by the lower supporting plate 24 and a casing 41 coupled thereto.
The inflow chamber 43 is connected to the heat transfer tubes 15 that are attached to the lower supporting plate 24. A lower portion of the casing 41 is provided with an inlet 42 through which the aqueous solution is introduced thereinto. An aqueous solution distributing plate 44 is horizontally placed above the inlet 42 within the inflow chamber 43. The plate 44 is provided with multiple passage holes 441 to enable the aqueous solution to flow uniformly. It is preferred that the casing 41 be detachably coupled to the lower supporting plate 24.
Referring to Fig. 2, a cylindrical upper casing 50 is coupled to the top of the upper support plate 22, and a top plate 79 is coupled to the top of the upper casing 50. A horizontal supporting plate 68 is provided in an inner space defined by the upper casing 50, the upper supporting plate 22 and the top plate 79. The driving unit 80 and the discharge unit 60 are disposed above and below the support plate 68, respectively. The discharge unit 60 is provided with an inclined guiding plate 64 for diagonally partitioning the space. The discharge chamber 61 is a space below the inclined plate 64. The outlet 61 is provided at an upper portion of a sidewall of the discharge chamber 61, i.e. a portion adjacent to an uppermost portion of the inclined plate 64. The aqueous solution including ice slurry transported to the discharge chamber 61 through the heat transfer tubes 15 is guided by the inclined plate 64 and discharged through the outlet 62. Thus, the ice slurry and the liquid aqueous solution are stably discharged without separating from each other. The inclined guiding plate 64 is provided with holes through which the scrapers 16 extend to the driving unit 80. There are gaps or apertures in the inclined guiding plate 64 so that a portion of the aqueous solution can flow to above the inclined guiding plate 64. The aqueous solution fills in the power transmission device chamber 82 through passages 681 provided in the supporting plate 68 so as to function as lubricant and coolant of a power transmission device. It is preferred that the passages 681 be mounted with filters for filtering out foreign materials from the aqueous solution. Fig. 5 shows another embodiment of the discharge unit. Referring to Fig. 5, the two inclined guiding plates 64a are configured such that those incline up from the center of the discharge unit to the side wall of the discharge chamber. At this time, the discharge chamber 61a may be provided with two or more outlets 62a. With such a structure, the height of the discharge chamber can be reduced.
Referring again to Fig. 2, the driving unit 80 is provided above the discharge unit 60. The driving unit 80 includes a driving device 90 provided on the top plate 79, and a power transmission device for delivering power from a driving device 90. The driving unit 80 includes the power transmission device chamber 82 between the top plate 79 and the support plate 68 to accommodate the power transmission device. The driving device 90 includes a rotation driving motor and a reduction device for adjusting the number of revolutions. A rotational shaft 92 of the driving device 90 is inserted into the power transmission chamber 82 while being maintained in a sealed state by means of a shaft-sealing member (also called a "shaft sealing") 91. A number of gears are provided within the power transmission device chamber 82 to construct the power transmission device for transmitting a rotational force. A primary driving gear 95 is mounted on the rotational shaft 92 of the driving device 90. A primary driven gear 70 is mounted on a rotational shaft of the scraper 16a positioned at the center of each cell 31 of the heat-exchange chamber 18. The primary driven gear 70 is engaged with the primary driving gear 95 to receive the rotational force. A secondary driving gear 72 is also mounted on the rotational shaft of the scraper 16a provided with the primary driven gear 70. A secondary driven gear 74 is mounted on a rotational shaft of each of the scrapers 16 surrounding the scraper 16a positioned at the center of each cell 31. The secondary driven gear 74 is engaged with the secondary driving gear 72 to receive the rotational force. With such a structure, the respective scrapers 16 and 16a are rotated at similar speeds by the driving device 90. Although not specifically illustrated in this embodiment, the diameter of the secondary driving gear is slightly larger than that of the secondary driven gear. Therefore, the peripheral scrapers 16 are rotated slightly faster than the central scraper 16a. This is to prevent unnecessary interference among the gears for the scrapers. Those skilled in the art can understand that since the central scraper and the peripheral scrapers are rotated in opposite directions in such a power transmission structure, the spiral directions of blades of the scrapers are also opposite to each other. Journaling devices such as ball bearings are installed in the support plate
68 to ensure the smooth rotation of such gear shafts (i.e., driving shafts or scrapers).
Meanwhile, an outlet 78 is provided on the side surface of the power transmission device chamber (also referred to as "gear chamber") 82. The aqueous solution for cooling and lubrication that has been introduced through the passages 681 of the support plate 68 is discharged to the outside through the outlet 78. The exiting aqueous solution joins the aqueous solution discharged from the discharge chamber 61. As for the aqueous solution for cooling and lubrication, the aqueous solution existing above the inclined guiding plate 64 is introduced into the power transmission device chamber 82 through the passages 681 provided in the support plate 68. Before the aqueous solution is introduced into the power transmission device chamber 82, foreign materials (mainly, metallic foreign materials) that may affect the operations of the gears are removed by means of the filters (not shown) mounted in the passages 681.
Although the driving unit is disposed at the uppermost portion of the ice slurry generator 10 in the present invention, the present invention is limited thereto. It can be understood by those skilled in the art that the driving unit can be alternatively disposed at the lowermost portion of the ice slurry generator 10.
Referring to Figs. 2, 6 and 7, the scrapers of the ice slurry generator are the same in view of their basic structures except the spiral directions thereof. Each scraper 16 includes a stem 161 corresponding to a central shaft, and a blade 162 formed along the periphery of the stem 161 at a predetermined angle. Although the scraper 16 can vary according to the size and structure of the ice slurry generator, it is made of plastic resin (for example, PE, POM, etc.) and may also be made of any materials having cold resistance, water resistance and rigidity. It is preferred that a metal insert be inserted into the stem 161 to reinforce the rigidity and straightness thereof. Referring to Fig 7, an upper surface (a downstream surface with respect to the flow direction of the aqueous solution) of the blade 162 includes a convex surface with a predetermined radius of curvature R in section, and a lower surface (an upstream surface with respect to the flow direction of the aqueous solution) of the blade 162 includes a slanted surface that is inclined at a predetermined angle θ and preferably, constitutes a spiral surface which is linear in section (this configuration is herein referred to as a "front-curved and rear- slanted" configuration). As an example, it is preferred that the radius of curvature R be generally 6 to 15 mm, and the angle θ be generally 10 to 20 degrees. A distal end of the blade 162 is established in such a manner that the curve directly joins the line. Since the outer diameter of the distal end is maintained constant throughout the blade, a gap g between the distal end and an inner surface of the relevant heat transfer tube 15 is constant. Preferably, the blade 162 is a multiple-start thread blade. In the embodiment shown in Figs. 2, 6 and 7, the blade is a triple-start thread blade. Therefore, since the heat transfer surface is scraped as many times as corresponds to the number of starts (three times in case of the triple-start thread blade) every one revolution of the scraper, the scraper can be operated at a low speed.
Meanwhile, referring to Figs. 6, 7 and 8, the aqueous solution is introduced from the inflow chamber 40 into spaces defined by the inner surface of the heat transfer tube, the stem 161 and the surfaces of the blade 162 as the scraper 16 is rotated, so that it can flow in the heat transfer tube. Referring to Fig. 8, the aqueous solution flows through the small gap g between the distal end of the blade 162 and the heat transfer tube 15 in a direction designated by an arrow as shown in Fig. 8 and sweeps away a film formed at the gap g. The aqueous solution is mixed up while passing through the gap g, thereby enhancing heat transfer and lowering the degree of supercooling in aqueous solution. Consequently, ice slurry can be generated in stable manner. This state is well shown in Fig. 8. The structure of the front-curved and rear-slanted scraper according to the present invention enables high heat transfer efficiency that is an advantage of the conventional whip rod type ice slurry generator, and stable transportation of ice slurry and low operational noises that are advantages of a scraper type ice slurry generator. Now, the operation of the ice slurry generator will be described in detail with reference to Figs. 2 and 3.
The liquid refrigerant is introduced into the heat exchange chamber 18 through the refrigerant inlet 99 provided at a lower portion of the heat-exchange chamber. The refrigerant introduced into the heat-exchange chamber 18 is uniformly distributed among and supplied to the respective unit cells 31 through the passage holes 171 of the lower refrigerant distributing plate 17. The liquid refrigerant supplied to the respective cells 31 flows upward, evaporates while taking heat away from the aqueous solution within the heat transfer tubes 15, and then escapes from the upper portion of the heat- exchange chamber 18 through the passage holes 141 of the upper refrigerant distributing plate 14. The gaseous refrigerant above the heat exchange chamber 18 is discharged toward the compressor (designated by reference numeral 1 in Fig. 1) through the refrigerant outlet 98.
The aqueous solution is introduced into the inflow chamber 43 through the inlet 42 of the inflow unit 40 provided at the lower portion of the ice slurry generator 10. The aqueous solution introduced into the inflow chamber 43 uniformly flows upward through the passage holes 441 on the aqueous solution distributing plate 44. The aqueous solution is sucked into the heat transfer tubes 15 by negative pumping pressure induced by the rotating scrapers 16. As the aqueous solution flows upward along the heat transfer tubes 15, heat in the aqueous solution is taken away by the refrigerant in the heat-exchange chamber 18 so that a portion of the aqueous solution can be subjected to phase change and thus become ice slurry. The aqueous solution containing the ice slurry flows into the discharge chamber 61 through the heat transfer tubes 15, is discharged through the outlet 62, and finally transported to and stored in the thermal storage tank (designated by reference numeral 5 in Fig. 1). At this time, a portion of the aqueous solution in the discharge chamber 61 flows into the upper space of guiding plate 64 through the holes on it. The aqueous solution then enters the power transmission device chamber 82 through the passages 681 of the supporting plate 68, performs cooling and lubricating functions and exits through the outlet 78. The exiting aqueous solution joins the aqueous solution discharged from the discharge chamber 61. Meanwhile, the filters are mounted in the passages 681 of the supporting plate 68 and the outlet 78 of the power transmission device chamber 82 to filter out foreign materials that are contained in the aqueous solution and may affect the operations of the gears.
With the use of the ice slurry generator constructed as above according to the present invention, the present design leads to high heat transfer efficiency which is an advantage of the existing whip rod type ice slurry generator, and stable transportation of ice slurry and reduced noise that are advantages of the existing scraper type ice slurry generator. Further, since the flow of the refrigerant is uniform, overall high heat transfer efficiency is improved. Moreover, the aqueous solution flows upward; thus, it significantly reduces problems of accumulation and clogging caused by separation of ice particle and aqueous solution resulting from density difference, thereby ensuring more stable operation. Finally, the driving unit provides improved durability and more reliable load distribution, prevention of introduction of foreign materials, and the like.
It can be understood by those skilled in the art that although the ice slurry generator has been described as being oriented vertically in the aforementioned embodiments, the present invention is not limited thereto and the ice slurry may be oriented horizontally.
Although the present invention has been described in connection with the preferred embodiments of the present invention, the present invention is not limited thereto. It will be apparent to those skilled in the art that various modifications and changes can be made thereto without departing from the sprit and scope of the present invention and will fall within the scope of the present invention.

Claims

1. An ice slurry generator, comprising: an inflow unit provided with an inlet through which an aqueous solution is introduced; a discharge unit provided with an outlet through which the aqueous solution is discharged; a heat exchange unit which is placed between the inflow unit and the discharge unit, and has an inlet and outlet for a refrigerant and heat transfer tubes extending between the inflow unit and discharge unit to define passages through which the aqueous solution passes from the inflow unit to the discharge unit; scrapers which are inserted into the respective heat transfer tubes and each of which has a stem and a spiral blade formed along a periphery of the stem; and a driving device to rotate the scrapers, wherein the blade has an upstream surface and a downstream surface with respect to the flow of aqueous solution, the downstream surface includes a curved surface having a curve in section, and the upstream surface includes a slanted surface directed to the stem.
2. The ice slurry generator as claimed in claim 1, wherein the curved surface and the slanted surface meet each other to form an edge.
3. The ice slurry generator as claimed in claim 2, wherein a gap between an inner surface of each heat transfer tube and the blade is minimized at the edge of the blade.
4. The ice slurry generator as claimed in any one of claims 1 to 3, wherein the curve is a portion of a circle or ellipse.
5. The ice slurry generator as claimed in any one of claims 1 to 4, wherein the slanted surface has a straight line in section.
6. The ice slurry generator as claimed in any one of claims 1 to 5, wherein the blade of each scraper has multiple-start spiral threads.
7. The ice slurry generator as claimed in any one of claims 1 to 6, wherein the inflow unit is disposed below the heat exchange unit, and the discharge unit is disposed above the heat exchange unit.
8. The ice slurry generator as claimed in claim 7, wherein the discharge unit is provided with an inclined guiding plate that guides ice slurry to the outlet.
9. The ice slurry generator as claimed in any one of claims 1 to 8, wherein the heat exchange unit includes cell partition walls for partitioning the heat transfer tubes into multiple unit cells each of which contains two or more heat transfer tubes, and a refrigerant distributing plate provided with multiple passage holes for uniformly supplying the introduced refrigerant to the respective cells.
10. The ice slurry generator as claimed in claim 9, wherein each cell contains one of the heat transfer tubes positioned at the center thereof and the remaining heat transfer tubes positioned along a circumference about the center thereof.
11. The ice slurry generator as claimed in claim 10, wherein a power transmission device is provided between the scraper installed in the central heat transfer tube and the scrapers installed in the peripheral heat transfer tubes so that a rotational force can be transmitted from the scraper in the center tube to the ones in peripheral tubes.
12. An ice slurry generator, comprising: a heat exchange unit which has an inlet and outlet for a refrigerant and a bundle of heat transfer tubes extending vertically to define passages for a aqueous solution performing heat exchange with the refrigerant; an inflow unit which is disposed below the heat exchange unit to be connected to the heat transfer tubes and provided with an inlet through which the aqueous solution is introduced; a discharge unit which is disposed above the heat exchange unit to be connected to the heat transfer tubes and provided with an outlet through which the aqueous solution is discharged; scrapers which are inserted into the respective heat transfer tubes and each of which has a stem and a spiral blade formed along a periphery of the stem; and a driving device for rotating the scrapers.
13. The ice slurry generator as claimed in claim 12, wherein the discharge unit is provided with inclined plates that guide ice slurry to the outlet.
14. The ice slurry generator as claimed in claim 13, wherein the inclined guiding plate in discharge chamber is installed such that one end is attached lower part of the side wall and the other end is attached to the upper part of the side wall where the outlet is positioned to guide ice slurry to the outlet.
15. The ice slurry generator as claimed in claim 13, wherein the two inclined guiding plates in discharging unit are installed such that one end of both plates are attached to the center of the bottom wall and the other ends are attached to the upper part of side wall to guide ice slurry to the two outlets that are installed on upper part of side wall.
16. The ice slurry generator as claimed in any one of claims 12 to 15, wherein a chamber housing power transmission device for driving the scrapers is placed above the discharge unit, and the chamber is supplied with the aqueous solution from the discharge unit.
17. The ice slurry generator as claimed in claim 16, wherein filters are provided between the power transmission device chamber and the discharge unit.
18. An ice slurry generator, comprising: an inflow unit provided with an inlet through which aqueous solution is introduced; a discharge unit provided with an outlet through which the aqueous solution is discharged; a heat exchange unit which is placed between the inflow unit and the discharge unit, and has an inlet and outlet for a refrigerant and heat transfer tubes for defining passages through which the aqueous solution performing heat exchange with the refrigerant passes between the inflow unit and discharge unit; and wherein the heat exchange unit includes cell partition walls for partitioning the heat transfer tubes into multiple unit cells each of which contains two or more heat transfer tubes, and a refrigerant distributing plate provided with multiple passage holes for uniformly supplying the introduced refrigerant to the respective cells.
19. The ice slurry generator as claimed in claim 18, further comprising scrapers which are inserted into the respective heat transfer tubes and each of which has a stem and a spiral blade formed along a periphery of the stem; and a driving device for rotating the scrapers.
20. The ice slurry generator as claimed in claim 19, wherein each cell contains one of the heat transfer tubes positioned at the center thereof and the remaining heat transfer tubes positioned along a circumference about the center thereof; and a power transmission device is provided between the scraper installed in the center tube and the scrapers installed in the peripheral tubes so that a rotational force can be transmitted from the scraper in the center tube to the ones in peripheral tubes.
21. A method of generating ice slurry in heat transfer tubes containing scrapers, each scraper having a spiral blade on a periphery thereof, comprising the steps of: supplying a refrigerant around the heat transfer tubes; and passing aqueous solution through the heat transfer tubes while rotating the scrapers, wherein in the step of passing the aqueous solution, a portion of the aqueous solution flows backward through gaps between inner walls of the heat transfer tubes and distal ends of the blades when the aqueous solution moves from an upstream side to a downstream side.
22. The method as claimed in claim 21, wherein the heat transfer tubes are placed vertically, and the step of passing the aqueous solution includes moving the aqueous solution upward.
PCT/KR2003/002397 2002-11-15 2003-11-08 Ice slurry generator WO2004046624A1 (en)

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AU2003277718A AU2003277718A1 (en) 2002-11-15 2003-11-08 Ice slurry generator

Applications Claiming Priority (4)

Application Number Priority Date Filing Date Title
KR20020071307 2002-11-15
KR10-2002-0071307 2002-11-15
KR10-2002-0081471A KR100513219B1 (en) 2002-11-15 2002-12-18 Slurry ice generator
KR10-2002-0081471 2002-12-18

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Cited By (4)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
WO2012007856A1 (en) * 2010-07-12 2012-01-19 Evert Frederik Potgieter Industrial shell and tube heat exchanger
WO2013018056A1 (en) * 2011-08-02 2013-02-07 Evert Frederik Potgieter Energy arrangement
JP2013542393A (en) * 2010-09-29 2013-11-21 ムック イム、ヒョ Ice making equipment
US8677768B2 (en) 2009-12-05 2014-03-25 Innovel 2000 Inc. System and method for purifying a first liquid content and simultaneously heating a second liquid content

Citations (3)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US4129015A (en) * 1977-04-22 1978-12-12 Morris Jr William F Ice storage and dispensing bin
US5884501A (en) * 1996-04-19 1999-03-23 Goldstein; Vladimir Ice-making machine and heat exchanger therefor
KR20000017696A (en) * 1999-06-21 2000-04-06 김용옥 Slurry ice generator for cool thermal storage system

Patent Citations (3)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US4129015A (en) * 1977-04-22 1978-12-12 Morris Jr William F Ice storage and dispensing bin
US5884501A (en) * 1996-04-19 1999-03-23 Goldstein; Vladimir Ice-making machine and heat exchanger therefor
KR20000017696A (en) * 1999-06-21 2000-04-06 김용옥 Slurry ice generator for cool thermal storage system

Cited By (7)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US8677768B2 (en) 2009-12-05 2014-03-25 Innovel 2000 Inc. System and method for purifying a first liquid content and simultaneously heating a second liquid content
WO2012007856A1 (en) * 2010-07-12 2012-01-19 Evert Frederik Potgieter Industrial shell and tube heat exchanger
EP2593728A4 (en) * 2010-07-12 2015-03-18 Evert Frederik Potgieter Industrial shell and tube heat exchanger
US9476628B2 (en) 2010-07-12 2016-10-25 Frederik Evert Potgieter Industrial shell and tube heat exchanger
JP2013542393A (en) * 2010-09-29 2013-11-21 ムック イム、ヒョ Ice making equipment
EP2623902A4 (en) * 2010-09-29 2016-11-16 Hyo Mook Lim Ice-making apparatus
WO2013018056A1 (en) * 2011-08-02 2013-02-07 Evert Frederik Potgieter Energy arrangement

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