High throughput freezer

Abstract

A system for rapidly cooling or freezing products by continuous convective and / or conductive heat transfer processes. In one example, the system includes a refrigeration system to generate a coolant and a cooling bath to contain the coolant, the cooling bath being in fluid communication with the refrigeration system. The system may further include a conveyor system including an inlet disposed on a first portion of the conveyor system and an outlet disposed on a second portion of the conveyor system. In various examples, the first portion is at least partially disposed in the cooling bath and the second portion is at least partially disposed out of the cooling bath, the second portion disposed after the first portion.

Description

HIGH THROUGHPUT FREEZERCROSS REFERENCE TO RELATED APPLICATION

[0001] This application claims the benefit of the filing date of US Provisional Patent Application No.: 63 / 455,125, filed March 28, 2023. The contents of which is hereby incorporated by reference in its entirety.FIELD OF THE INVENTION

[0002] The present disclosure generally relates to a cooling environment, and more particularly, to a system for freezing products in a cooling environment.BACKGROUND

[0003] Many products are transported or stored below ambient temperatures. This is generally accomplished by immersing the product in cooled air produced by heat exchange with a compressor-driven refrigeration circuit. Product storage and transport often entail logistical constraints such as access to electrical power, mechanical limitations, and the like. In these situations, an auxiliary thermal mass that undergoes a phase change at a temperature below ambient, such as water ice, is separately frozen and stored with the product to keep it cool through conduction by contact and passive air convection.

[0004] Freezing materials is accomplished by their immersion in chilled air that circulates by passive or forced convection. These prior art methods are typically limited by the pace of convective energy transfer with air as the medium, both at the product and at the interface between air and the refrigeration circuit. An object of the present invention is to maximize the rate with which heat is transferred from the product to the chilled fluid. A second object of the present invention is to reduce the size, weight, and power of a continuous freezer for maximum yield of frozen product per time interval. A third object of the present invention is to maximize the energy efficiency of a continuous freezer system.SUMMARY

[0005] Disclosed herein is a system for cooling a product, including a refrigeration system to generate a liquid coolant and a cooling bath to contain the coolant. The cooling bath being in fluid communication with the refrigeration system. The system may further include a conveyor system including an inlet disposed on a first portion of the conveyor system and anoutlet disposed on a second portion of the conveyor system. In some examples, the first portion is at least partially disposed in the cooling bath and the second portion is at least partially disposed out of the cooling bath, the second portion disposed after the first portion.

[0006] In some variations, the refrigeration system includes a first refrigeration system providing the coolant and a second refrigeration system to generate a cooling airflow. In such examples, the cooling airflow generated by the second refrigeration system passes over at least part of the second portion of the conveyor system.

[0007] In other variations, the coolant may have a thermal conductivity greater than 0.15 Watts per meter Kelvin (W / nrK). For example, the coolant may be one of a group composed of ethylene glycol, propylene glycol, fluorocarbon fluids, and brine. Furthermore, in some variations, the coolant is recirculated through the cooling bath via the refrigeration system.

[0008] In yet other variations, the second portion of the conveyor system is disposed above the cooling bath. Additionally, the second portion of the conveyor system is configured to drain excess coolant into the cooling bath by gravity or convective shear. Further, the conveyor system includes a conveyor speed and the first portion defines a submerged length. The conveyor speed and the length of the submerged length are configurable to define a predetermined residence time in the cooling bath. In such examples, the predetermined residence time to cool the product from a first temperature to a second temperature, the second temperature lower than the first temperature.

[0009] Also disclosed herein is a method of cooling a product including moving a product into a cooling bath and out of the cooling bath using a conveyor system, the product having a first temperature when being moved into the cooling bath. In accordance with the method, the product leaving the cooling bath having a second temperature, the second temperature lower than the first temperature. Furthermore, the method includes draining coolant off the product.

[0010] In some variations, draining coolant off the product includes passing a cooling airflow over the product. Also, draining coolant off the product further includes draining coolant off the product and into the cooling bath.

[0011] In other variations, passing the product along the conveyor system, into the cooling bath, includes submerging the product in the cooling bath for a residence time. In suchexamples, the residence time is adjusted by adjusting a conveyor speed of the conveyor system.

[0012] In yet other variations, further comprising recirculating the coolant in the cooling bath and maintaining the coolant at a threshold temperature. Additionally, the threshold temperature may be less than the second temperature.

[0013] Furthermore, when moving the product into and out of the cooling bath the coolant may have a thermal conductivity greater than 0.15 Watts per meter Kelvin (W / m-K).

[0014] Also disclosed herein is a system for cooling a product, the system including a refrigeration system to generate a coolant and a cooling flow of the coolant. The cooling flow in fluid communication with the refrigeration system. The system may further include a conveyor system having an inlet disposed on a first portion of the conveyor system and an outlet disposed on a second portion of the conveyor system. In some examples, the first portion is at least partially disposed in the cooling flow and the second portion is at least partially disposed out of the cooling flow, the second portion disposed after the first portion.

[0015] In some variations, the coolant has a thermal conductivity greater than 0.15 Watts per meter Kelvin (W / m-K). Additionally, the coolant is one of a group composed of ethylene glycol, propylene glycol,, fluorocarbon fluids, and brine.

[0016] In other variations, the cooling flow includes a stream of coolant. Additionally or alternatively, the cooling flow includes a spray of coolant.

[0017] Also disclosed herein is a system for rapid and continuous convective cooling of a product. The system includes a refrigerant loop comprised of a fluid that changes phase to absorb heat in thermal contact with a coolant fluid that maintains its liquid phase over the range of desired product temperatures; a conveyer that immerses product in a bath of chilled coolant fluid and thence to a flow of chilled air that remove excess fluid from the product.

[0018] Also disclosed herein is a method of cooling a product. The method includes moving a product through a cooling bath using a conveyor system; selecting the conveyer system speed and fluid residence time to ensure a required temperature change of the product; and draining coolant off the product.

[0019] Also disclosed herein is a system of cooling a product. The system includes a conveyer belt of thermally conductive material in contact with thermally conductive rollers that are actively cooled by a refrigerant circuit; counterweight and tensioning mounts toaccommodate product expansion or contraction while maintaining thermal contact therewith as it is conveyed along the belt.BRIEF DESCRIPTION OF DRAWINGS

[0020] The present disclosure is described in the following detailed description in conjunction with the drawings, wherein:

[0021] FIG. 1 illustrates a schematic diagram of a refrigeration system configured for use in the cooling systems of the present application.

[0022] FIG. 2 illustrates a side view of a convective heat transfer system.

[0023] FIG. 3 illustrates a graph of temperature change of a product frozen over time as a function of the convective heat transfer coefficient.

[0024] FIG. 4 illustrates a side view of a conductive heat transfer system.

[0025] FIG. 5 illustrates a graph of temperature change of a product freezing over time as a function of the conductive heat transfer coefficient.

[0026] FIG. 6 is a side view of a flow diagram corresponding to cooling three products in accordance with the present disclosure.

[0027] FIG. 7 illustrates a graph of cooling dynamics of the products of FIG. 6 for air and water heat transfer.

[0028] FIG. 8 is a perspective view of an example cooling system made in accordance with the present disclosure.

[0029] FIG. 9 is a perspective view of a second example cooling system made in accordance with the present disclosure.

[0030] FIG. 10 is a perspective view of a third example cooling system made in accordance with the present disclosure.

[0031] FIG. 1 1 is a perspective view of an alternative configuration of the third example cooling system made in accordance with the present disclosure.

[0032] FIG. 12 is a perspective view of a fourth example cooling system made in accordance with the present disclosure.

[0033] FIG. 13 is a side view of a fifth example cooling system made in accordance with the present disclosure.

[0034] FIG. 14 is a side view of a sixth example cooling system made in accordance with the present disclosure.

[0035] Skilled artisans will appreciate that elements in the figures are illustrated for simplicity and clarity and have not necessarily been drawn to scale. For example, the dimensions and / or relative positioning of some of the elements in the figures may be exaggerated relative to other elements to help to improve understanding of various embodiments of the present invention. Also, common but well-understood elements that are useful or necessary in a commercially feasible embodiment are often not depicted in order to facilitate a less obstructed view of these various embodiments. It will further be appreciated that certain actions and / or steps may be described or depicted in a particular order of occurrence while those skilled in the art will understand that such specificity with respect to sequence is not actually required. It will also be understood that the terms and expressions used herein have the ordinary technical meaning as is accorded to such terms and expressions by persons skilled in the technical field as set forth above except where different specific meanings have otherwise been set forth herein.DETAILED DESCRIPTION

[0036] Definitions

[0037] The term convective heat transfer coefficient, as used herein, is the rate of heat transfer between a solid surface and a fluid per unit surface area per unit temperaturedifference. In symbolic form, h =where h is the heat transfer coefficient in Watts / meter2Kelvin (W / m2K), q is the local heat flux density (W / m2), and AT is the temperature difference in Kelvin (K) between the solid and the fluid.

[0038] The term conductive heat transfer, as used herein, is the flow of heat between two static materials that are in intimate thermal contact, as occurs between two solids or a solid and a liquid or gel that is not immobile.

[0039] The term radiative heat transfer, as used herein, is the flow of heat between two objects by electromagnetic radiation and moderated by wavelength-dependent differential emissivities.

[0040] The term target product, as used herein, is a finite sample of material to be cooled or frozen that is optionally encased in a thermally thin metal or polymer film.

[0041] The term refrigerant, as used herein, is a fluid that cools by evaporation and is subsequently condensed by compression and Joule-Thomson expansion.

[0042] The term coolant, as used herein, is a liquid that transports heat without changing to a gas or solid phase over the range of temperatures required for operation.

[0043] Commercially Freezing Products

[0044] Freezing products in bulk may be time consuming and costly. For example, freezing a large quantity of products in bulk using cold air may take days and even weeks to completely freeze. Additionally, large quantities of product may be bulky and heavy, which increases overall costs. In order to cool such large batches of product, helical cooling systems can be utilized to provide a continuous process for adequately cooling each product.

[0045] Example Refrigeration System

[0046] FIG. 1 illustrates the operation of an example refrigeration system 100 for use in the high throughput refrigerators disclosed herein (described in greater detail in connection with FIGS. 8-14). The refrigeration system 100 includes an evaporator 102 and a condenser 104. A refrigerant is passed in a closed fluid system between the evaporator 102 and the condenser 104. The refrigerant changes phase to a vapor within the evaporator 102, absorbing thermal energy from the coolant. The refrigerant passes as a vapor along conduit 1 12 to the condenser 104. Within the condenser 104, the refrigerant changes phase to a liquid and is returned to the evaporator 102 along conduit 114. The phase change of the refrigerant from a vapor to a liquid is governed by Joule-Thomson expansion. In various examples, the refrigeration system 100 may further include a pump (not shown) to convey the refrigerant through the refrigeration system 100.

[0047] Warmed coolant fluid 132 passes over the evaporator 102 and is cooled down. The freshly cooled coolant 134 is passed over product 142. As the cooled down fluid 134 passes over the product 142, the fluid is warmed up to be warm fluid 132. In some examples, warm fluid 136 returns to the evaporator 102 to be cooled again.

[0048] Convective Cooling

[0049] FIGS. 2 and 3 illustrate an example convection heat transfer system 202 and a graph 302 of representative convection temperature change data. Prior art convection based freezers use air as the coolant fluid and flow it around the product. As shown in FIG. 2, airflow 204 passes around a product 206. The rate of heat flow between the product 206 and the airflow 204 is governed by convective, rather than conductive, heat transfer (discussed in greater detail below). As is well recognized by those practiced in the art of thermal engineering, convective heat transfer depends on the physical properties of the fluid, whether gaseous or liquid, the solid, and the flow conditions. The ratio of convective heat transfer to temperature difference, also known as the convective heat transfer coefficient h, is not a property of the fluid alone. It is an experimentally determined parameter whose value depends on all the variables influencing convection including the surface geometry, the nature of fluid motion, the properties of the fluid, the temperature, and the bulk fluid velocity. The impact of these variables on the rate of convective heat transfer for specific conditions can be calculated precisely using finite- element computational software as described above.

[0050] Representative ranges for convective heat transfer coefficients are based on the range of achievable solid and fluid properties including thermal conductivity, heat capacity, viscosity, density, and accessible flow velocities and are summarized in Table 1 . The convective heat transfer coefficient to or from gases range from about 2 to no more than approximately 300 W / m2K, while that for liquids ranges from about 50 to as much as 10,000 W / m2K.Table 1

[0051] The time required to complete the conversion from ambient temperature to the target temperature of the frozen product is a fundamental, rate-limiting unit operation for a continuous freezer. Decreasing this time permits higher throughput for a fixed refrigerant architecture, or a more compact device for specific throughput requirements. An aspect of the present invention is to reduce, and preferably minimize, this time by employing liquid phase coolants and flow conditions that provide convective heat transfer rates above those accessible for cold gases, such as air. A second aspect of the invention is to further reduce this time byproviding releasable, thermally conductive contact between a product and a solid surface whose thermal mass is substantially larger and is maintained at the targeted freezing temperature.

[0052] Conductive Cooling

[0053] FIG. 4 and 5 illustrate an example conduction heat transfer system 402 and a graph 502 of representative conduction temperature change data. The fastest cooling for a given product 404 is via physical contact between the product 404 and two large thermal masses 406 that may be actively cooled to maintain a constant temperature. The example product 404 illustrates a pouch having a thermally thin membrane filled with water or aqueous gel.

[0054] The graph 502 in FIG. 5 displays the maximum temperature of the target product (being 3 centimeters thick) at different times when its initial temperature is 70 °F and it contacts large thermal masses held at 0 degrees Fahrenheit (°F), -20°F, and -40 °F. At 0°F the water freezes in fifteen minutes and takes twenty to come to equilibrium at 0°F. Contact with the thermal mass at -40°F freezes the product in a little over five minutes and equilibrates to -40°F in eleven minutes. The intermediate case with the contact at -20 °F freezes in eight and equilibrates in twelve minutes. The flat portions of the curves in FIG. 5 and FIG. 3, where the derivative of temperature per unit time (dT / dt) is approximately zero, correspond to the times required for the coolant to remove the enthalpy of solidification from the product. These conductive heat transfer examples illustrate constraints imposed by heat transfer through the dynamic mixture of water and ice. Conductive cooling as described herein produces the shortest possible freezing times for this set of material properties and geometry. Times and freezing curves vary systematically with the fundamental thermodynamic and geometric properties of the product and are straightforwardly calculable by methods familiar to those practiced in the art of thermal engineering.

[0055] FIG. 6 illustrates a cooling testing experiment 600. In the testing experiment 600, a first product 612, a second product 614, and a third product 616 are in a cooling flow 622. In one example, the cooling flow 622 is air and in a second example the cooling flow 622 is liquid. The first, second, and third products 612, 614, 616 are initially disposed in the environment at an initial temperature of 75 degrees Fahrenheit (°F). The cooling flow 622, initially at 35°F, flows over the first, second, and third products 612, 614, 616, sequentially at average velocity of 10 cm / s. After the cooling flow 622 passes over the first product 612, the first product 612 is cooled and the cooling flow 622 is warmed. The warmed cooling flow 622 cools the second product614, but not as quickly as the first product 612. The second product 614 cools slower because the temperature difference between the warmed cooling flow 622 and the second product 614 is less than the difference between the cooling flow 622 and the first product 612. As a result, the first product 612 cools quicker than the second product 614 and the third product 616. Similarly, the second product 614 cools quicker than the third product 616.

[0056] FIG. 7 illustrates a graph 700 corresponding to cooling data 702 measured in the testing experiment 600. The cooling data 702 includes a first data set 704 (corresponding to the cooling flow 622 of FIG. 6 being air), a second data set 706 (corresponding to the cooling flow 622 of FIG. 6 being water). As shown in the graph 700, the first, second, and third products 612, 614, 616 of FIG. 6 cool much faster when the cooling flow 622 is liquid. The liquid-cooled products 612, 614, 616 cool faster because the convective heat transfer coefficient of the liquid is much greater than the convective heat transfer coefficient of air. Also, the difference in cooling rates among the three products is less with water than with air coolant because the heat capacity of the former is much greater than that of the latter.

[0057] Example Improved Cooling Systems

[0058] FIG. 8 illustrates a first example cooling system 800 made in accordance with the present disclosure. The cooling system 800 includes a conveyor system 802, a cooling bath 804, and a first refrigeration system 806. In some examples, the cooling system 800 may further include a second refrigeration system 808. In various examples, one or both of the refrigeration systems 806, 808 may be similar or identical to the refrigeration system 100 of FIG. 1. As illustrated in FIG. 8, at least part of the conveyor system 802 is disposed in the cooling bath 804.

[0059] The conveyor system 802 of FIG. 8 is a spatially efficient helical conveyor system for moving a product along a conveyor path 812 having an inlet 814a and an outlet 814b. The inlet 814a is disposed on a first portion 818a of the conveyor path 812, a submerged portion 818b of the conveyor path 812 is disposed in the cooling bath 804, and the outlet 814b is disposed on a second portion 818c of the conveyor path 812. The first portion 818a, the submerged portion 818b, and the second portion 818c may be part of single conveyor system 802. The first portion 818a, the submerged portion 818b, and the second portion 818c may alternatively be a first, second, and third conveyor, respectively. Conveyor system 802 may include a material that is hydrophobic. The conveyor system 802 may include Teflon™ as an example.

[0060] The conveyor system 802 transports a product 822 along the conveyor path 812 from the inlet 814a along the first portion 818a to the submerged portion 818b and then to the second portion 818c and out the outlet 814b in the implementation shown. The conveyor system 802 may include retention devices to retain the position of the product 822 relative to at least the submerged portion 818b of the conveyor system 802 when the product 822 is being moved through the coolant 832 contained within the cooling bath 804. The retention devices may include spring loaded fingers and / or an actuatable cage to prevent the product 822 from floating when its density is less that that of the coolant. The location of the inlet 814a and the outlet 814b can be different than shown and / or the conveyor system 802 may include a conveyor path 812 that is not helical.

[0061] The cooling bath 804 is shown disposed around and beneath the conveyor system 802 in the implementation shown and contains a coolant 832. The cooling bath 804 may be differently shaped and / or positioned, however. Additionally, while the first portion 818a and the second portion 818c are outside the cooling bath 804, the submerged portion 818b is shown disposed in the cooling bath 804 and the coolant 832. The second portion 818c of the conveyor system 802 is shown positioned above and / or extending from the submerged portion 818b. The first, submerged, and second portions 818a, 818b, 818c may be directly coupled and / or part of the same conveyor. Alternatively, the first, submerged, and second portions 818a, 818b, 818c may be separate conveyors. In various examples, the first portion 818a is dry, the submerged portion 818b is at least partially disposed in the coolant 832, and the second portion 818c is not disposed in the coolant 832 but may be partially wet from coolant 832. The flow of coolant within the coolant bath is arranged by inlets, outlets, pumps, and other necessary fluid transfer equipment to ensure efficient convective heat transfer from the product to the fluid before it is returned to the refrigerant circuit for recooling.

[0062] In various examples, the cooling system 800 includes the coolant 832 at a threshold temperature. The threshold temperature is colder than a predetermined temperature of a product 822 being conveyed by the conveyor system must be cooled to. In one example, if the product 822 needs to be cooled to -5 degrees Celsius (°C), the coolant can be maintained at -10°C. In the various examples, the product is cooled to the predetermined temperature quicker when the difference between the predetermined temperature and the threshold temperature is larger.

[0063] In operation of the cooling system 800, the product 822 may have a first temperature when the product 822 is at a first position 824a of the conveyor system disposedproximate the inlet 814a and the product 822 may have a threshold, second temperature when the product 822 exits the cooling bath 804. The second temperature is less than the first temperature and, in some examples, the second temperature may be a temperature beneath the freezing point of the product 822.

[0064] In some examples, the first portion 818a and the submerged portion 818b of the conveyor system 802 includes an initial drop 826 to submerge the product 822 into the coolant 832. Additionally, the submerged and second portions 818b, 818c may define a helical conveyer path 812 that moves the product in a direction generally indicated by arrow 836. The product 822 proceeds to a second position 824b disposed in the cooling bath 804 and in the coolant 832. While the product 822 is disposed in the coolant 832, the product 822 is cooling and / or freezing. In some examples, the conveyor path 812 defines a conveyor speed and the submerged portion 818b defines a submerged length and either the conveyor speed or the submerged length can be adjusted to obtain a sufficient or predetermined residence time. As used herein, “residence time” refers to the time the product 822 is submerged and a “sufficient residence time” is the time necessary to cool the product 822 from the first temperature to a second temperature (e.g., a frozen temperature).

[0065] The submerged portion 818b of the conveyor system 802 passes the product 822 to the second portion 818c and a position 824c above the cooling bath 804. The second portion 818c assists with draining the coolant 832 off the product 822 passing along the conveyor path 812 and / or allows the product 822 to dry.

[0066] In some examples, during operation of the cooling system 802, the product 822 is at the threshold second temperature as the product 822 leaves the coolant 832. Subsequently, the second portion 818c of the conveyor system transports the product 822 to the third position 824c. The second portion 818c further conveys the product 822 to a fourth position 824d and out through the outlet 814b. The product 822 may be entirely dried of the coolant 832 when the product 822 is at the fourth position 824d, in some implementations. In some examples, the product 822 may not be entirely dried of the coolant before passing through the outlet 814b.

[0067] In various examples, the coolant 832 is a fluid that has a high density (e.g., is a liquid). Additionally, the coolant 832 has a high thermal conductivity but will still readily drain off the product 822 or otherwise be dried off the product 822 without leaving a residue. For example, the coolant 832 could be ethylene glycol (e.g., 30% ethylene glycol, 60% ethyleneglycol, etc.), propylene glycol (e.g., 30% propylene glycol, helical 60% propylene glycol, etc.), brine (e.g., salt water), a fluorocarbon liquid, or any solution of the foregoing. In some implementations, the coolant 832 has a thermal conductivity of greater than 0.15 Watts per meter kelvin (W / m-K) (0.087 British Thermal Units per hour foot degree Fahrenheit (BTU / h-ft- °F)). Table 2 presents the thermal conductivities of air and a few potential coolants.

[0068] The coolant 832 may have a freezing point below the freezing point of the product or below a desired cooling temperature of the product. The coolant 832 has a lower freezing point in some implementations to enable the coolant 832 to remain a liquid while in the cooling bath 804. For example, if the product needs to be cooled below -15 degrees Celsius (°C), the freezing temperatures of water, ethylene glycol, and brine (shown in Table 2 below) are too high to effectively cool the product to -15°C. But, in the foregoing example, propylene glycol can cool the product to -15°C because propylene glycol is a liquid at -15 °C and freezes beneath -60.0qC.Table 2

[0069] The coolant 832 may be selected for other characteristics as well. For example, the coolant 832 may be selected to be chemically compatible with the product 822, so that the coolant 832 does not degrade the product 822 or its packaging. The coolant 832 may be selected to deter the product 822 from floating off of the first portion 818a in the cooling bath 804 (e.g., because the density of the product 822 is greater than the density of the coolant 832). Additionally, the coolant 832 drains off of the product 822 after the product 822 exits the cooling bath 804. In the example of FIG. 8, the coolant 832 falls back into the cooling bath 804 because the conveyor system 800 is a helical conveyor system and disposed above the cooling bath 804. In some implementations, the coolant 832 has a lower viscosity (e.g., less than 100 centipoise (cP)) to ensure proper recycling of the coolant 832.

[0070] The refrigeration system 806 generates and maintains the coolant 832 at the threshold temperature. In some examples, the refrigeration system 806 is in fluid communication (and thermal communication) with cooling bath 804 and includes a pump to forcibly recirculate and recycle coolant 832 through the cooling bath 804. In the implementationshown, warm coolant 832 exits the cooling bath 804 via recirculation inlet 852a, passes through the refrigeration system 806, and cold coolant 832 returns to the cooling bath 804 via recirculation outlet 852b. In such examples, the refrigeration system 806 absorbs thermal energy in the coolant 832 and expels the thermal energy away from the coolant 832 and the cooling system 800. Additionally, the refrigeration system 806 can include a temperature sensor (not shown) disposed in the cooling bath 804 and a controller (not shown) to control the temperature of the coolant 832 in the cooling bath 804.

[0071] The cooling system 800 may include a second refrigeration system 808 that generates a cooling airflow 872 to dry and / or further cool the product 822 after the product 822 exits the cooling bath 804. For example, the cooling airflow 872 can further cool and freeze the product 822 such that the product 822 is fully cooled or frozen before the product 822 exits the cooling system 800 at the outlet 814b. Additionally, the cooling airflow 872 may include a high airflow velocity sufficient to blow coolant 832 off the product 822 and into the cooling bath 804 and / or otherwise dry the product 822. The cooling airflow 872, in various examples, is provided to dry and / or ensure drainage of the coolant 832 off the product 822.

[0072] FIG. 9 illustrates a second example cooling system 900. The cooling system 900 includes a conveyor system 902, a cooling bath 904, and a refrigeration system 906. As illustrated in FIG. 9, at least part of the conveyor system 902 is disposed in the cooling bath 904. Similar to the cooling system 800 of FIG. 8, the cooling system 900 may also include a second refrigeration system to dry product.

[0073] The conveyor system 902 of FIG. 9 is a spatially efficient helical conveyor system for moving a product along a conveyor path 912 having an inlet 914a and an outlet 914b. The inlet 914a is adjacent the outlet 914b. The conveyor path 912 helically drops from the inlet 914a to a transitional conveyor portion 916. The conveyor path 912 then helically rises from the transitional conveyor portion 916 to the outlet 914b. A product (e.g., product 822) is passed along the conveyor path 912 from the inlet 914a, down to the transitional conveyor portion 916, and back up to the outlet 914b. Conveyor system 902 may include a material that is hydrophobic. The conveyor system 1202 may include Teflon™ as an example.

[0074] The cooling bath 904 is shown disposed around the conveyor system 902. The cooling bath 904 can be filled with a coolant (similar or identical to coolant 832). The cooling bath 904 may be differently shaped and / or positioned, however. The depth of coolant can be determined to ensure every product is sufficiently frozen or cooled before leaving the coolantand being conveyed through the outlet 914b. Additionally, the coolant may be maintained at a threshold temperature colder than a predetermined temperature of the product (as described above in connection with FIG. 8). In some examples, the air temperature surrounding the conveyor system 900 is maintained below the predetermined temperature to prevent the product from warming after emerging from the coolant. Additionally, the cooling system 900 could include a blower to dry the product emerging from the coolant bath.

[0075] The refrigeration system 906 generates and maintains the coolant at the threshold temperature. In various examples, the refrigeration system 906 operates similar or identically to the refrigeration system 100 described in connection with FIG. 1 . In some examples, the refrigeration system 906 is in fluid communication (and thermal communication) with cooling bath 904 and includes a pump to forcibly recirculate and recycle coolant 932 through the cooling bath 904.

[0076] FIG. 10 illustrates a third example cooling system 1000. The cooling system 1000 includes a conveyor system 1002, a plurality of sprayer assemblies 1004, and a refrigeration system 1006. In the present example, each of the sprayer assemblies 1004 includes a plurality of nozzles 1005. As shown in FIG. 10, the sprayer assembly 1004 includes seven nozzles 1005 distributed in a semi-circular arc, but could include more or fewer nozzles1005 and in different geometric configurations than shown. As illustrated in FIG. 10, at least part of the conveyor system 1002 is disposed in an enclosed tube 1008.

[0077] The conveyor system 1002 of FIG. 10 is an enclosed helical conveyor system for moving a product along a conveyor path 1012. The conveyor path 1012 includes an inlet 1014a and an outlet 1014b. The conveyor path 1012 includes a tube 1008 to partially enclose the conveyor path 1012. Disposed in the tube 1008 is the sprayer system 1004. The sprayer system 1004 includes a plurality of sprayer nozzles 1014 along the length of the conveyor path 1012. The sprayer system 1004 sprays or mists coolant (e.g., coolant 834) on the conveyor path 1012 and product (e.g., product 822) on the conveyor path 1012. In various examples, the sprayer system 1004 coats the product with coolant but does not spray enough coolant to cause the product to float. Conveyor system 1102 may include a material that is hydrophobic. The conveyor system 1102 may include Teflon™ as an example.

[0078] In various examples, the cooling system 1000 includes the coolant at a threshold temperature (described in greater detail in connection with FIG. 8). The refrigeration system1006 operates similar or identically to the refrigeration system 100 described in connection withFIG. 1. In some examples, the refrigeration system 1006 receives and recycles coolant from the spray system 1004 and pumps the coolant back to the spray system 1004. In the present example, after the coolant is sprayed onto the product, the coolant flows down the tube through the grate 1022. The coolant then collects in a pan 1024. The refrigeration system 1006 cools and pumps the coolant from the pan through a central tower 1026 back to the plurality of sprayer systems 1004. In the present example, each sprayer system 1004 is fed by one of a plurality of coolant feed arms 1028. By utilizing a plurality of feed arms 1028 and sprayer systems 1004, a product passing through the cooling system 1000 will be in regular, contact with coolant that was recently cooled to the threshold temperature by the refrigeration system 1006.

[0079] FIG. 1 1 illustrates a cooling system 1 100. The cooling system 1 100 is an alternative arrangement of the third example cooling system 1000. In the present example, the cooling system 1100 is substantially similar to the cooling system 1000 and includes substantially identical components (similarly numbered to the components of FIG. 10).

[0080] In contrast to the cooling system 1000, the cooling system 1 100 includes a plurality of sprayer assemblies 1 104 that are disposed along the length of the tube 1108. As shown in FIG. 11 , the cooling system 1100 includes six sprayer assemblies 1104, but could include more or fewer sprayer assemblies 1104. Each of the sprayer assemblies 1104 receives recently cooled coolant from the central tower 1122 and a central distributor 1 132. Each of the sprayer assemblies 1104 includes a plurality of sprayer heads (not shown) along the length of the sprayer assemblies 1104. The sprayer heads could be similar or identical to the nozzles 1005 shown in FIG. 10. The plurality of sprayer assemblies 1104 are easier to install, maintain, and repair than the sprayer assemblies 1004 of FIG. 10.

[0081] FIG. 12 illustrates a fourth example cooling system 1200. The cooling system 1200 includes a conveyor system 1202, a cooling bath 1204, and a first refrigeration system 1206. In some examples, the cooling system 1200 may further include a second refrigeration system 1208. As illustrated in FIG. 12, no portion of the conveyor system 1202 is disposed in the cooling bath 1204. In some examples, at least a portion of the conveyor system 1202 may be disposed in the cooling bath 1204 in other examples, however.

[0082] The conveyor system 1202 of FIG. 12 is a linear conveyor including a conveyor path 1212 having an inlet 1214a and an outlet 1214b. The conveyor path 1212 transports the product 1222 from the inlet 1214a to the outlet 1214b. The inlet 1214a is disposed on a firstportion 1218a of the conveyor path 1212 and the outlet 1214b is disposed on a second portion 1218c of the conveyor path 1212. A product 1222 is transported along the conveyor path 1212 from the inlet 1214a, along the first portion 1218a to the second portion 1218c and out the outlet 1214b in the implementation shown. In some examples, the conveyor system 1202 may including a conveyor path 1212 that is helical.

[0083] The cooling bath 1204 is disposed beneath the conveyor system 1202 and includes a coolant 1232. The cooling bath 1204 may be differently shaped and / or positioned, however. In various examples, the coolant 1232 has a threshold temperature that is colder than the desired, second temperature of the product leaving the cooling system 1200. For example, if a product needs to be cooled to -5 degrees Celsius (°C), the coolant 1232 may need to be maintained at -10 °C.

[0084] In operation of the cooling system 1200, a product 1222 may have a first temperature when the product 1222 is at a first zone 1218a disposed proximate the inlet 1214a and the product 1222 may have a threshold second temperature when the product 1222 exits the cooling system 1200 at the outlet 1214b. The second temperature is less than the first temperature. The conveyor system 1202 transports the product 1222 from a first zone 1218a, through a wet zone 1218b, and a second zone 1218c. The wet zone 1218b of the conveyor system 1202 is disposed at and after the cooling flow 1234 while the product is substantially submerged under or covered by coolant 1232. The refrigeration system 1206 may include various nozzles and sprayers (not shown) to generate the cooling flow 1234. The cooling flow 1234 is made of a stream or spray of liquid coolant 1232. After the conveyor system 1202 passes the product 1222 through the wet zone 1218b, the product 1222 is cooled and / or frozen to a second temperature. In the present example, the wet zone 1218b is configured to facilitate coolant drippings 1236 falling from the product 1222 into the cooling bath 1204. Before reaching the outlet 1214b, the conveyor path 1212 passes the product 1222 through the second zone 1218c where most or all of the coolant 1232 has drained into the cooling bath 1204. In some examples, the cooling flow 1234 cools the temperature of the product 1222 in the wet zone 1218b to the desired, second temperature. The conveyor system 1202 then transports the product 1222 out of the cooling system 1200 via the outlet 1214b. While the cooling system 1200 is shown with one cooling flow 1234 (or cooling spray), in some examples, the cooling system 1200 could include two or more cooling flows 1234 or cooling sprays.

[0085] The first zone 1218a, the wet zone 1218b, and the second zone 1218c may be part of single conveyor system 1202. The first zone 1218a, the wet zone 1218b, and the secondzone 1218c may alternatively be a first, second, and third conveyor, respectively. Conveyor system 1 02 may include a material that is hydrophobic. The conveyor system 1202 may include Teflon™ as an example. The conveyor system 1202 may also include retention devices to retain the position of the product 1222 relative to at least the wet zone 1218b of the conveyor system 1202 when the product 1222 is being moved through the cooling path 1234. The retention devices may include spring loaded fingers and / or an actuatable cage.

[0086] In various examples, the coolant 1232 is selected for the same reasons and characteristics as the coolant 832. As a result, the coolant 1232 may be identical or similar to the coolant 832. For example, the coolant 1232 should have a high thermal conductivity (e.g., above 0.15 Watts per meter kelvin (W / m-K) (0.087 British Thermal Units per hour foot degree Fahrenheit (BTU / h-ft- °F)). Additionally, the freezing point of the coolant is, preferably, below 0 degrees Celsius (°C).

[0087] The first refrigeration system 1206 maintains the coolant 1232 at the threshold temperature. In various examples, the refrigeration system 1206 includes a typical heat pump having a compressor, condenser, expansion valve, and an evaporator. In the implementation shown, warm coolant 1232 exits the cooling bath 1204 via recirculation inlet 1252a to reach the refrigeration system 1206, and cold coolant 1232 returns to the cooling bath 1204 via cooling flow 1234. In such examples, the refrigeration system 1206 absorbs thermal energy in the coolant 1232 and expels the thermal energy away from the coolant 1232 and the cooling system 1200. In some examples, the refrigeration system 1206 further includes a pump 1254 to forcibly recirculate and recycle coolant 1232 through the refrigeration system 1206. Additionally, the refrigeration system 1206 can include a temperature sensor (not shown) and a controller (not shown) to control the temperature of the coolant 1232 in the cooling bath 1204.

[0088] Additionally, in some examples, the cooling system 1200 may include a second refrigeration system 1208. In such examples, the second refrigeration system 1208 generates a cooling airflow 1272 to further cool the product 1222 after the product 1222 exits the cooling flow 1234. For example, the product 1222 can be nearly or partially frozen and the cooling airflow 1272 can further cool and freeze the product 1222 such that the product 1222 is fully cooled or frozen before the product 1222 exits the cooling system 1200 at the outlet 1214b. Additionally, the cooling airflow 1272 may include a high airflow velocity sufficient to blow coolant 1232 off the product 1222 and into the cooling bath 1204. The cooling airflow 1272, in various examples, is provided to ensure drainage of the coolant 1232 off the product 1222.

[0089] FIG. 13 illustrates another alternative cooling system 1300. The cooling system 1300 includes a conveyor system 1302, a cooling bath 1304, and a first refrigeration system 1306. In some examples, the cooling system 1300 may further include a second refrigeration system 1308. As illustrated in FIGS. 8 and 9, at least part of the conveyor system 1302 is disposed in the cooling bath 1304.

[0090] The conveyor system 1302 of FIG. 13 moves a product along a conveyor path 1312 having an inlet 1314a and an outlet 1314b. The inlet 1314a is disposed on a first portion 1318a of the conveyor path 1312, a submerged portion 1318b of the conveyor path 1312 is disposed in the cooling bath 1304, and the outlet 1314b is disposed on a second portion 1318c of the conveyor path 1312. The first portion 1318a, the submerged portion 1318b, and the second portion 1318c may be part of single conveyor system 1302. The first portion 1318a, the submerged portion 1318b, and the second portion 1318c may alternatively be a first, second, and third conveyor, respectively. Conveyor system 1302 may include a material that is hydrophobic. The conveyor system 1302 may include Teflon™ as an example.

[0091] The conveyor system 1302 transports a product 1322 along the conveyor path 1312 from the inlet 1314a along the first portion 1318a to the submerged portion 1318b and then to the second portion 1318c and out the outlet 1314b in the implementation shown. The conveyor system 1302 include a retention device 1328 to retain the position of the product 1322 relative to at least the submerged portion 1318b of the conveyor system 1302 when the product 1322 is being moved through the coolant 1332 contained within the cooling bath 1304. The retention device 1328 includes a conveyer belt configured to secure the product 1322 against the conveyor system 1302. The location of the inlet 1314a and the outlet 1314b can be different than shown. In some examples, the retention device 1328 may be additionally configured to cool the product 1322 via conductive heat transfer (discussed in greater detail in connection with FIG. 14).

[0092] The cooling bath 1304 is shown disposed around and beneath the conveyor system 1302 in the implementation shown and contains a coolant 1332. The cooling bath 1304 may be differently shaped and / or positioned, however. Additionally, while the first portion 1318a and the second portion 1318c are outside the cooling bath 1304, the submerged portion 1318b is shown disposed in the cooling bath 1304 and the coolant 1332. The second portion 1318c of the conveyor system 1302 is shown extending from the submerged portion 1318b. The first, submerged, and second portions 1318a, 1318b, 1318c may be directly coupled and / or part of the same conveyor. Alternatively, the first, submerged, and second portions 1318a, 1318b,1318c may be separate conveyors. In various examples, the first portion 1318a is dry, the submerged portion 1318b is at least partially disposed in the coolant 1332, and the second portion 1318c is not disposed in the coolant 1332 but may be partially wet from coolant 1332.

[0093] In various examples, the cooling system 1300 includes the coolant 1332 at a threshold temperature. The threshold temperature is colder than a predetermined temperature of a product 1322 being conveyed by the conveyor system must be cooled to. For example, if the product 1322 needs to be cooled to -5 degrees Celsius (°C), the coolant may need to be maintained at -10 °C.

[0094] In operation of the cooling system 1300, the product 1322 may have a first temperature when the product 1322 is at a first position 1324a of the conveyor system disposed proximate the inlet 1314a and the product 1322 may have a threshold, second temperature when the product 1322 exits the cooling bath 1304. The second temperature is less than the first temperature and, in some examples, the second temperature may be a temperature beneath the freezing point of the product 1322.

[0095] In some examples, the first portion 1318a and the submerged portion 1318b of the conveyor system 1302 includes an initial drop 1326 to submerge the product 1322 into the coolant 1332. Additionally, the submerged and second portions 1318b is a curved travel path, but may define a helical portion. The product 1322 proceeds to a second position 1324b disposed in the cooling bath 1304 and in the coolant 1332. While the product 1322 is disposed in the coolant 1332, the product 1322 is cooling and / or freezing. In some examples, the conveyor path 1312 defines a conveyor speed and the submerged portion 1318b defines a submerged length and either the conveyor speed or the submerged length can be adjusted to obtain a sufficient or predetermined residence time. As used herein, “residence time” refers to the time the product 1322 is submerged and a “sufficient residence time” is the time necessary to cool the product 1322 from the first temperature to a second temperature (e.g., a frozen temperature).

[0096] The submerged portion 1318b of the conveyor system 1302 passes the product 1322 to the second portion 1318c and a position 1324c outside the cooling bath 1304. The second portion 1318c assists with draining the coolant 1332 off the product 1322 passing along the conveyor path 1312 and / or allows the product 1322 to dry.

[0097] In some examples, during operation of the cooling system 1302, the product 1322 is at the threshold second temperature as the product 1322 leaves the coolant 1332.Subsequently, the second portion 1318c of the conveyor system transports the product 1322 to the third position 1324c. The second portion 1318c further conveys the product 1322 to a fourth position 1324d and out through the outlet 1314b. The product 1322 may be entirely dried of the coolant 1332 when the product 1322 is at the fourth position 1324d, in some implementations. In some examples, the product 1322 may not be entirely dried of the coolant before passing through the outlet 1314b.

[0098] In various examples, the coolant 1332 is similar or identical to the coolant 832 described in connection with FIG. 8. Additionally, the coolant 1332 has a high thermal conductivity but will still readily drain off the product 1322 or otherwise be dried off the product 1322 without leaving a residue. For example, the coolant 1332 could be ethylene glycol, propylene glycol, brine (e.g., salt water), or any solution of the foregoing.

[0099] The coolant 1332 may have a freezing point below the freezing point of the product or below a desired cooling temperature of the product. The coolant 1332 has a lower freezing point in some implementations to enable the coolant 1332 to remain a liquid while in the cooling bath 1304. For example, if the product needs to be cooled below -15 degrees Celsius (°C), the freezing temperatures of water, ethylene glycol, and brine (shown in Table 1 above) are too high to effectively cool the product to -15°C. But, in the foregoing example, propylene glycol can cool the product to -15°C because propylene glycol is a liquid at -15°C and freezes beneath -60.0 °C.

[0100] The coolant 1332 may be selected for other characteristics as well. For example, the coolant 1332 may be selected to be chemically compatible with the product 1322, so that the coolant 1332 does not degrade the product 1322 or its packaging. The coolant 1332 may be selected to deter the product 1322 from floating off of the first portion 1318a in the cooling bath 1304. Additionally, the coolant 1332 drains off of the product 1322 after the product 1322 exits the cooling bath 1304. In the example of FIG. 13, the coolant 1332 may be collected and recycled back to the cooling back 1304. In some implementations, the coolant 1332 has a lower viscosity (e.g., less than 100 centipoise (cP)) to ensure proper recycling of the coolant 1332.

[0101] The refrigeration system 1306 generates and maintains the coolant 1332 at the threshold temperature. In various examples, the refrigeration system 1306 includes a heat pump having a compressor, condenser, expansion valve, and an evaporator (discussed in greater detail in connection with FIG. 1 ). In some examples, the refrigeration system 1306 is in fluid communication with cooling bath 1304 and includes a pump to forcibly recirculate and recyclecoolant 1332 through the cooling bath 1304. In the implementation shown, warm coolant 1332 exits the cooling bath 1304 via recirculation inlet 1352a, passes through the refrigeration system 1306, and cold coolant 1332 returns to the cooling bath 1304 via recirculation outlet 1352b. In such examples, the refrigeration system 1306 absorbs thermal energy in the coolant 1332 and expels the thermal energy away from the coolant 1332 and the cooling system 1300. Additionally, the refrigeration system 1306 can include a temperature sensor (not shown) disposed in the cooling bath 1304 and a controller (not shown) to control the temperature of the coolant 1332 in the cooling bath 1304.

[0102] The cooling system 1300 may include a second refrigeration system 1308 that generates a cooling airflow 1372 to dry and / or further cool the product 1322 after the product 1322 exits the cooling bath 1304. For example, the cooling airflow 1372 can further cool and freeze the product 1322 such that the product 1322 is fully cooled or frozen before the product 1322 exits the cooling system 1300 at the outlet 1314b. Additionally, the cooling airflow 1372 may include a high airflow velocity sufficient to blow coolant 1332 off the product 1322 and into the cooling bath 1304 and / or otherwise dry the product 1322. The cooling airflow 1372, in various examples, is provided to dry and / or ensure drainage of the coolant 1332 off the product 1322.

[0103] FIG. 14 illustrates yet another alternative cooling system 1400 utilizing conduction. The cooling system 1400 includes a conveyor system 1402, cooling rollers 1482, and a first refrigeration system 1406. In some examples, the cooling system 1400 may further include a second refrigeration system.

[0104] The conveyor system 1402 transports a product 1422 along the conveyor path 1412 from the first end 1414a through a cooling portion 1418 and out the outlet 1414b. In the illustrated example, the cooling portion 1418 includes an upper cooling track 1430a and a lower cooling track 1430b. Each of the upper and lower cooling tracks 1430a, 1430b includes at least one cooling roller 1432. For example, the upper and lower cooling tracks 1430a, 1430b each include two cooling rollers 1432. Each cooling roller 1432 includes an internal channel 1434 for passing coolant 1436. The coolant 1436 cools the cooling roller 1432 which cools a thermally conductive band 1438 (described in greater detail below) to conductively cool the product 1422. The cooling rollers 1432 cool the thermally conductive track 1438 which cool the product 1422. As shown in FIG. 14, the cooling portion 1418 could include four or more cooling rollers 1432. For example, each of the upper and lower cooling tracks 1430a, 1430b include a third cooling roller 1432 to maintain the temperature of the cooling band 1438. Additionally, the conveyorsystem 1402 could include more than one cooling portion 1418. In some examples, the product 1422 may further be cooled by convection before or after the cooling portion 1418.

[0105] The thermally conductive band 1438 is configured to efficiently cool the product 1422. As a result, the thermally conductive band 1438 is made of a material that has a high thermal conductivity (e.g., metal). Additionally, the thermally conductive band 1438 and roller 1432 are designed to provide enough thermal mass to properly cool the product 1422. For example, the thermally conductive band 1438 could include a loop of linked metal panels, each metal panel being at least 2 centimeters (cm) thick. In various examples, the cooling rollers 1432 maintains the thermally conductive bands 1438 at or below a threshold temperature (described above in connection with coolant 832 of FIG. 8) in order to cool the product 1422 at or below a predetermined temperature before the product 1422 reaches the outlet 1414b.

[0106] In some examples, the cooling system 1400 may include counterweight and tensioning mounts (not shown) to appropriately tension the conductive band 1438. The counterweight and tensioning mounts may adjust the tension of the conductive bands 1438 as the conductive bands 1438 change length due to thermal expansion and contraction. Additionally, the counterweight and tensioning mounts may improve thermal contact between the product 1422 and the conductive band 1438.

[0107] Those skilled in the art will recognize that a wide variety of modifications, alterations, and combinations can be made with respect to the above described examples without departing from the spirit and scope of the invention(s) disclosed herein, and that such modifications, alterations, and combinations are to be viewed as being within the ambit of the inventive concept(s).

Claims

CLAIMSWhat is claimed is:1 . A system for cooling a product, comprising: a refrigeration system to generate a liquid coolant; a cooling bath to contain the coolant, the cooling bath in thermal communication with the refrigeration system; and a conveyor system including an inlet disposed at a first portion of the conveyor system and an outlet disposed at a second portion of the conveyor system, the first portion at least partially disposed in the cooling bath and the second portion at least partially disposed out of the cooling bath, the second portion disposed after the first portion.

2. The system of claim 1 , wherein the refrigeration system includes a first refrigeration system providing the coolant and a second refrigeration system to generate a cooling airflow.

3. The system of claim 2, wherein the cooling airflow generated by the second refrigeration system passes over at least part of the second portion of the conveyor system.

4. The system of claim 1 , wherein the coolant has a thermal conductivity greater than 0.15 Watts per meter Kelvin (W / m-K).

5. The system of claim 4, wherein the coolant is one of ethylene glycol, propylene glycol, a fluorocarbon fluid, or brine.

6. The system of claim 1 , wherein the coolant is recirculated through the cooling bath via the refrigeration system.

7. The system of claim 1 , wherein the second portion of the conveyor system is disposed above the cooling bath.

8. The system of claim 7, wherein the second portion of the conveyor system is configured to drain excess coolant into the cooling bath.

9. The system of claim 1 , wherein the conveyor system includes a conveyor speed and the first portion defines a submerged length.

10. The system of claim 9, wherein the conveyor speed and the submerged length enable a predetermined residence time in the cooling bath.1 1 . The system of claim 10, wherein the predetermined residence time to cool the product from a first temperature to a second temperature, the second temperature being lower than the first temperature.

12. The system of claim 1 , wherein the conveyor system is a helical conveyor system.

13. The system of claim 12, wherein the outlet is disposed adjacent to the inlet.

14. A method of cooling a product, comprising: moving a product into a cooling bath containing a liquid coolant and out of the cooling bath using a conveyor system, the product having a first temperature when being moved into the cooling bath, the product leaving the cooling bath having a second temperature, the second temperature being lower than the first temperature; and draining coolant from the cooling bath off the product by gravity and / or convective shear.

15. The method of claim 14, wherein draining the coolant from the cooling bath off the product includes passing a cooling airflow over the product.

16. The method of claim 15, wherein in draining coolant off the product, the coolant is drained into the cooling bath.

17. The method of claim 14, wherein passing the product into the cooling bath includes submerging the product in the cooling bath for a residence time.

18. The method of claim 17, wherein the residence time is adjusted by adjusting a conveyor speed of the conveyor system.

19. The method of claim 14, further comprising recirculating the coolant in the cooling bath and maintaining the coolant at a threshold temperature.

20. The method of claim 19, wherein in maintaining the coolant at the threshold temperature, the threshold temperature is less than the second temperature.21 . The method of claim 14, wherein in moving the product into and out of the cooling bath, the coolant has a thermal conductivity greater than 0.15 Watts per meter Kelvin (W / m-K).

22. A system for cooling a product, comprising: a refrigeration system to generate a liquid coolant; a cooling flow of the coolant, the cooling flow in thermal communication with the refrigeration system; and a conveyor system including an inlet disposed on a first portion of the conveyor system and an outlet disposed on a second portion of the conveyor system, the first portion as least partially disposed in the cooling flow and the second portion at least partially disposed out of the cooling flow, the second portion disposed after the first portion.

23. The system of claim 22, wherein the coolant has a thermal conductivity greater than 0.15 Watts per meter Kelvin (W / m-K).

24. The system of claim 23, wherein the coolant is one of a group consisting of ethylene glycol, propylene glycol, fluorocarbon fluids, and brine.

25. The system of claim 23, wherein the cooling flow includes a stream of liquid coolant.

26. The system of claim 23, wherein the cooling flow includes a spray of liquid coolant.

27. A system for rapid and continuous convective cooling of a product comprising: a refrigerant loop comprised of a fluid that changes phase to absorb heat in thermal contact with a coolant fluid that maintains its liquid phase over a range of desired producttemperatures; a conveyer that immerses product in a bath of chilled coolant fluid and thence to a flow of chilled air that remove excess fluid from the product.

28. A method of cooling a product, comprising: moving a product through a cooling bath using a conveyor system; selecting a speed of the conveyer system and fluid residence time to ensure a required temperature change of the product; and draining coolant off the product.

29. A system of cooling a product comprising: a conveyer belt of thermally conductive material in contact with thermally conductive rollers that are actively cooled by a refrigerant circuit; counterweight and tensioning mounts to accommodate product expansion or contraction while maintaining thermal contact therewith as it is conveyed along the conveyer belt.

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