Product over-blow management assembly

Abstract

An assembly for managing product overblow in a gas processing system may include a first deflector assembly configured to substantially prevent product from exiting a product processing zone of a product carrying unit of the gas processing system. The assembly may also include a second deflector assembly configured to direct over-blown product that has exited the product processing zone substantially into an over-blow landing zone that is separate from a heat exchanger assembly of the gas processing system.

Description

[0001] Cross-references to related applications This application claims the benefit of U.S. Provisional Application No. 63 / 498714, filed April 27, 2023, the entire contents of which are incorporated herein by reference. Background Technology

[0002] In the food industry, fluidized bed freezers, or "fluidized" freezers, are commonly used to rapidly freeze food as individual units (a process known as individual quick freezing, or "IQF" for short). Fluidization can be used for products such as vegetables, fruits, and berries. Fluidization causes solid particles to float in an upward direction within a flow of gas or liquid. Fluidization occurs during freezing when particles of similar shape and size are subjected to an upward flow of cold air. Using this technique, products can be placed in a trough with multiple perforations. The food to be frozen can be transported on a perforated conveyor (e.g., a belt or tray) that defines the trough. Cold air is forced upward through the perforated conveyor and the product bed, "fluidizing" the food to form the bed of products.

[0003] A known problem with this type of freezer is so-called product overblow, which means that food or portions thereof leave the product area with the airflow. Overblow products can have at least two problems: (1) overblow products are lost from the production process, thus reducing the total output of the process; and (2) overblow products may end up in unwanted locations in the freezer, such as aisles, evaporator coils, etc.

[0004] Regarding the second question, overblown product during refrigeration production can eventually lead to airflow blockage. For example, evaporator coils are particularly prone to blockage by overblown product, which affects cooling capacity and airflow. Furthermore, production shutdowns for defrosting / cleaning the refrigeration unit limit its capacity, which in turn results in lost revenue for the producer. Additionally, evaporator coils, which are easily blocked by overblown product, are difficult to clean, increasing downtime. Frequent defrosting and / or cleaning also increases maintenance costs.

[0005] To accommodate the fluidized bed on the conveyor, the freezer may include "tray sides" mounted on both sides of the conveyor. In the product zone, the tray sides slope outwards, gradually increasing the surface area for circulating airflow. Theoretically, this increased surface area should mean a decrease in air velocity, thus reducing the tendency for food / debris to leave the product zone with the airflow. However, it has been found that the increased surface area does not actually reduce air velocity. Instead, a recirculation zone is formed in the upper part of the freezer, and the upward air velocity is not reduced.

[0006] To further attempt to reduce air velocity and pressure drag, the tray sides can include bottom openings that extend along the sides of the conveyor. If overblown product passes through the openings in the tray sides, it typically does not reach the location that is causing the problem (e.g., the evaporator coil). However, such openings result in product yield loss, and the openings do not significantly reduce the upward air velocity.

[0007] Some freezer systems are designed to include more complex air flow paths between the conveyor and the evaporator coil such that overblown product does not reach the coil. For example, in the system shown and described in EP 2 261 583 Al, the air must flow down the sides of the evaporator assembly before it travels upward to the evaporator assembly. Any product particles or debris, as well as snow formed during production, will settle onto the freezer floor due to gravity and thus will not reach the evaporator coil. This solution does not address the problem of food / debris exiting the product zone, but rather focuses on separating the overblown product from the air flow before it reaches the evaporator coil. Furthermore, this solution can only be implemented on larger freezers, such as sequential defrost freezers (e.g., JBT’s FLoFREEZE® sequential defrost (SD) freezers), because they require more space due to the more complex flow path as compared to standard (non-SD) freezers.

[0008] Accordingly, there is a need for improved systems and methods to manage product overblowing in a fluid bed freezer or “flow” freezer or other gas processing technology. SUMMARY

[0009] This overview is intended to provide a simplified introduction to a series of concepts that are further described below in the DETAILED DESCRIPTION. This overview is not intended to identify key features of the claimed subject matter, nor is it intended to be used to determine the scope of the claimed subject matter.

[0010] In some aspects, the technology described herein relates to a product overblow management assembly for a gas processing system configured to process a product by circulating a processing gas from a heat exchanger assembly through a product carrying unit, the product overblow management assembly comprising: a first deflector assembly configured to substantially prevent product from exiting a product processing zone of the product carrying unit; and a second deflector assembly configured to substantially direct overblown product that has exited the product processing zone into an overblown landing area that is separate from the heat exchanger assembly.

[0011] In some aspects, the technology described herein relates to a gas processing system comprising: a housing; a heat exchanger assembly; a gas circulation assembly for circulating a process gas within the housing; a product carrying unit configured to support a product to be processed with a process gas that is circulated within the housing and upward through the product carrying unit; and a product overblow management assembly comprising: a first deflector assembly configured to substantially prevent product from exiting a product processing zone of the product carrying unit; and a second deflector assembly configured to substantially direct overblown product that has exited the product processing zone into an overblow landing area that is separate from the heat exchanger assembly.

[0012] In some aspects, the technology described herein relates to a method of product overblow management for a gas processing system configured to process a product by circulating a process gas from a heat exchanger assembly through a product carrying unit, the method comprising: circulating the process gas from the heat exchanger to the product carrying unit; substantially preventing product from exiting a product processing zone of the product carrying unit; and substantially directing overblown product that has exited the product processing zone into an overblow landing area that is separate from the heat exchanger assembly. This Summary is provided to introduce a selection of concepts in a simplified form that are further described below in the DETAILED DESCRIPTION. This Summary is not intended to identify key features of the claimed subject matter, nor is it intended to be used as an aid in determining the scope of the claimed subject matter. BRIEF DESCRIPTION OF DRAWINGS

[0013] The foregoing aspects and many of the attendant advantages of this application will become more readily appreciated as the same become better understood by reference to the following detailed description, when taken in conjunction with the accompanying drawings, wherein: Figure 1 is a first side isometric view of a product overblow management assembly formed in accordance with an example embodiment of the disclosure, the assembly incorporated into an example flow freezer.

[0014] Figure 2 is a second side isometric view of the product overblow management assembly of Figure 1 and an example flow freezer.

[0015] Figure 3 is a top isometric view of the product overblow management assembly of Figure 1 and an example flow freezer.

[0016] Figure 4 is a front isometric view of the product overblow management assembly of Figure 1 and an example flow freezer.

[0017] Figure 5 is a front view of the product overblow management assembly of Figure 1 and an example flow freezer.

[0018] Figure 6 is a graphical image of a computational fluid dynamic (CFD) flow field simulation of an exemplary flow freezer product overblow management assembly employing a flow director incorporated into Figure 1 Figure 1 is a graphical image of a computational fluid dynamic (CFD) flow field simulation of an exemplary flow freezer product overblow management assembly employing a flow director incorporated into

[0019] Figure 7 is a graphical image of a computational fluid dynamic (CFD) flow field simulation of an exemplary flow freezer product overblow management assembly employing a flow director incorporated into Figure 1

[0020] Figure 8 is a graphical image of a computational fluid dynamic (CFD) product overblow simulation of an exemplary flow freezer product overblow management assembly employing a flow director incorporated into Figure 1 Figure 1

[0021] Figure 9 is a graphical image of a computational fluid dynamic (CFD) product overblow simulation of an exemplary flow freezer product overblow management assembly employing a flow director incorporated into Figure 1

[0022] Figure 10 is a table comparing product overblow data between a product overblow management assembly of Figure 1 and a prior art product overblow management assembly incorporated into a flow freezer of Figure 1 Figure 9

[0023] Figure 11 is a flow diagram depicting an exemplary method for managing product overblow for a gas processing system. DETAILED DESCRIPTION

[0024] Aspects of the present disclosure relate to improved systems and methods for managing product overblow in a gas processing system, such as a fluid bed freezer or "flow" freezer (i.e., a "product overblow management assembly"). While exemplary product overblow management assemblies are described with reference to a fluid bed freezer, it should be understood that the product overblow management assemblies described herein can be applicable to other gas processing systems, such as drying applications, heating applications, etc.

[0025] Generally, the product overblow management assembly is applicable to integration into a gas processing system having a relatively small overall footprint, such as a standard (non-SD) freezer, as compared to larger systems, such as a sequential defrost freezer. However, the product overblow management assembly is universal in that it is not limited to smaller systems. Rather, the product overblow management assembly can also be applicable to other types of systems and / or larger systems, such as a sequential defrost freezer.

[0026] ​​​​​​​Generally, the product overblow management assembly is configured to reduce or otherwise minimize product overblow (e.g., reduce the amount of product exiting the product zone). Moreover, if product does exit the product zone, the product overblow management assembly is configured to minimize the amount of overblow that ends up in undesirable areas of the gas handling system (e.g., the evaporator coil). Conversely, the product overblow management assembly is configured to direct overblow to a safe location that is easily removed during a cleaning process.

[0027] The product overblow assembly can be designed to effectively minimize product overblow and prevent overblow from reaching undesirable areas (e.g., the evaporator coil). However, to be effective, the product overblow management assembly for a gas handling system must also not significantly impact system (e.g., freezer) performance. The product overblow management assemblies described herein are configured to minimize product overblow and prevent overblow from reaching undesirable areas while substantially maintaining system (e.g., freezer) performance. For example, when using the product overblow management assemblies described herein, the airflow resistance of the gas handling system is minimized. The airflow resistance caused by the product overblow management assembly is low enough that it does not limit the airflow of the gas handling system; and thus, it does not slightly reduce the throughput of the freezer.

[0028] Figures 1-5 A product overblow management assembly 102 formed in accordance with an example embodiment of the disclosure is depicted that is incorporated into an example gas handling system (i.e., a flow freezer 104). Generally, the flow freezer 104 is configured to quickly and individually freeze food products (e.g., vegetables, fruits, berries, shellfish, etc.) using fluidization techniques. The product overblow management assembly 102 is configured to minimize the amount of product that exits the processing or product zone of the flow freezer 104 and it also substantially prevents overblow from reaching the evaporator coil of the freezer. At the same time, the product overblow management assembly 102 is universally used in application and minimizes the impact on freezer performance.

[0029] Aspects of an example flow freezer 104 will first be described. As noted above, a flow freezer processes food products to produce IQF products by floating the food products in an upwardly directed stream of processing media (e.g., gas or liquid). If a gas is used, the processing media is preferably air, however other gases can be used. For example, nitrogen or carbon dioxide can be used to process sensitive products that need to be processed in a protected atmosphere.

[0030] The flow freezer 104 includes a product-carrying unit 106 that extends substantially along the length of the interior compartment of the freezer for supporting the product as it is treated with the treatment medium, thereby defining a product treatment zone 108. The product-carrying unit 106 can take any suitable configuration, such as a tray, an elongated trough, and / or an endless belt with perforations, openings, apertures, etc. through which the upward flow of the treatment medium can pass as the product moves along the length of the freezer. The tray, trough, belt, etc. can be defined by any suitable material, such as stainless steel, mesh material, rubber, plastic, etc. and any combination thereof. The perforations, apertures, etc. defined in the product-carrying unit 106 can have any suitable size, shape, and arrangement. For example, the openings can have a diameter of about 4 millimeters (4 mm), and the total open area of the tray, belt, etc. can be about 20%.

[0031] The product-carrying unit 106 is configured to move the product along the length of the interior compartment of the freezer as it is treated with the treatment medium. If the product-carrying unit 106 is configured as a tray or an elongated trough, the product can be conveyed through the flow freezer 104 by setting the trough at a slight incline. Additionally or alternatively, the product can be conveyed along the product-carrying unit 106 by introducing an asymmetric vibration to the tray or trough in a manner known in the art.

[0032] In the depicted embodiment, the product-carrying unit 106 is configured as a first conveyor belt 110a and a second conveyor belt 110b ("IQF track") that are substantially coaxially aligned. The first conveyor belt 110a can be at a different level than the second conveyor belt 110b to define a dual-zone fluidized product treatment zone 108 or two separate pressure chambers to support different stages of fluidization, such as crust-freezing and core-freezing.

[0033] An infeed assembly (not shown) can be located upstream of the first conveyor belt 110a for placing the untreated food product onto the belt, and a collection assembly or another assembly (such as a conveyor assembly for transport to another treatment system) can be located downstream of the second conveyor belt 110b. A vibration assembly (not shown) can be used with the product-carrying unit 106 for ensuring uniform distribution of the food product being transported to support dehydration of the food product, etc.

[0034] The flow freezer 104 includes a gas handling system 112 configured to cool and circulate cooling air within the freezer such that the cooling air flows upward through the product handling zone 108 to treat the food product. In this regard, the gas handling system 112 can include a heat exchanger assembly 114 and a gas circulation assembly 116. The heat exchanger assembly 114 can be any suitable assembly configured to cool the air after it passes through the product handling zone 108 of the product carrier unit 106 such that it can be recirculated to the product handling zone 108 to treat successive product streams. In the depicted exemplary embodiment, the heat exchanger assembly 114 is a collection of an appropriate number of evaporator coils 118 (three coil assemblies are shown) for providing cooling air upward through the product handling zone along the length of the product handling zone.

[0035] In the illustrated embodiment, the heat exchanger assembly 114 has the capacity to supply cooling air substantially along the length of the product handling zone 108. In this regard, the heat exchanger assembly 114 supplies a cooling treatment gas to the product handling zone 108 to create an at least partially fluidized product bed in the product handling zone (see Figure 6 For example, the temperature of the treatment gas that fluidizes the product can be in the range of -20°C to -35°C.

[0036] The gas circulation assembly 116 is configured to circulate the cooled treatment gas (or "air" hereinafter) from the heat exchanger assembly 114, through the product handling zone 108 of the product carrier unit 106, and back to the heat exchanger assembly 114 for cooling. In the depicted exemplary embodiment, the gas circulation assembly 116 is a collection of an appropriate number of fans 120 for circulating the cooling gas along the length of the product handling zone and back to the heat exchanger assembly 114. In the illustrated embodiment, the gas circulation assembly 116 includes five evenly spaced fans 120, with one fan "missing" at an axial location that is generally at the transition between the first conveyor belt 110a and the second conveyor belt 110b.

[0037] The gas handling system 112 is optimally positioned within the flow freezer 104 by a support structure (e.g., a frame 122). The frame 122 or other support structure generally positions the evaporator coils 118 above the product handling zone 108 and the fans 120 below the product handling zone 108. In this regard, the evaporator coils 118 are placed on a substantially horizontal platform 124 that is defined at a height that is substantially equal to or above the top surface of the product carrier unit 106 (e.g., the top surface of the first conveyor belt 110a). The substantially horizontal platform 124 also defines a horizontal partition within the interior of the flow freezer 104 that substantially separates the cooling air exiting the evaporator coils 118 from the incoming warm air.

[0038] The fan 120 is located in a substantially vertical partition 126 of the frame 122 that extends substantially laterally downward (toward the product carrier unit 106) from a substantially horizontal deck 124 of the frame 122 on a side of the frame 122 away from the freezer interior wall. The substantially vertical partition 126 is also positioned substantially transverse to the longitudinal axis of the product carrier unit 106, such that the fan 120 can be positioned vertically in the vertical partition to move air from a low pressure zone 128 defined below the evaporator coil 118 to a high pressure zone 130 defined below the product carrier unit 106. The fan 120 or other air moving device of the gas circulation assembly 116 is selected to generally define air circulation within the freezer interior suitable for product processing (e.g., fluidization). For example, in the exemplary flow freezer 104, the fan 120 can have the capacity to produce an air volume flow of approximately 10-12 m3 / s. It should be appreciated that the capacity of the gas circulation assembly 116 can be increased or decreased for certain gas processing systems or products being processed to achieve the desired air circulation characteristics. 3

[0039] With the evaporator coil 118 and fan 120 arranged in the above-described configuration or a similar configuration, air is circulated in a circular manner within the interior of the flow freezer 104. More specifically, air flows downward through the evaporator coil 118, where the warm air is cooled. The cooled air is drawn downward into the low pressure zone 128 below the evaporator coil 118, and then substantially laterally through the fan 120 into the high pressure zone 130. The cooled air is drawn substantially upward through the openings of the product carrier unit 106 and through the product processing zone 108 of the product carrier unit 106. After exiting the product processing zone 108, the warm air (caused by heat exchange between the air and the fluidized product) moves substantially laterally through the upper interior of the flow freezer 104 (not shown), and then substantially downward into the heat exchanger assembly 114 for cooling.

[0040] By circulating air in the above-described manner, food products are effectively fluidized as they move along the product carrier unit 106 in the product processing zone 108. The fluidization effect can be improved by introducing vibrations, such as by pulsing the air or by vibrating the product carrier unit 106. In this regard, the gas processing system 112 can also include a pulser assembly (not shown) and a bypass assembly for controlling the air flow through the product processing zone 108.

[0041] ​The pulser assembly and / or bypass assembly 154 can be defined at least in part by airlocks, dampers, vents or valves (e.g., vent 156), hatches or ports (e.g., port 158), etc. (i.e., "pulsers" or "bypass mechanisms"). Each pulser of the pulser assembly (not shown) can be selectively opened to allow process gas to leak from the high pressure zone 130 into an area between the product carrying unit 106 and the heat exchanger assembly 114 (e.g., the overblow landing area 146 described below). By quickly closing the opened pulser, the pressure in the high pressure zone 130 can be increased, thereby creating a "pulsing" of gas through the openings of the product carrying unit 106. The pulsers can be used to facilitate the initiation of product fluidization. Each pulser can be opened and closed separately from the other components, e.g., with controllable actuators.

[0042] The bypass mechanisms of the bypass assembly 154 (which can include hatches, vents, etc. located in the second overblow landing assembly plate 150 or another component of the overblow landing area 146, as described below) can be used to further control the flow of gas through the flow freezer 104. For example, the bypass mechanisms can be used to reduce the velocity of the gas flow through the product carrying unit 106 to fine tune the amount of fluidization of the product bed.

[0043] Reference is made to Figures 1-5 Example embodiments of the product overblow management assembly 102 will now be described in more detail. As described above, the product overblow management assembly 102 is configured to reduce or otherwise minimize product overblow (e.g., reduce the amount of product exiting the product zone 108). Furthermore, if product does exit the product zone 108, the product overblow management assembly is configured to minimize the amount of overblow that ultimately enters the undesirable areas of the gas processing system 112 (e.g., the evaporator coils 118). Instead, the product overblow management assembly 102 is configured to direct the overblow to a safe location that is easily removed during a cleaning process.

[0044] Computational fluid dynamics (CFD) simulations were performed to evaluate the product overblow management assembly 102, e.g., by comparing the product overblow management assembly 102 to prior art assemblies used on substantially similar flow freezers. Figure 6 (flow field) and Figure 8 (particle tracking) show the results of CFD simulations of the product overblow management assembly 102, Figure 7 (flow field) and Figure 9 (particle tracking) show the results of CFD simulations in comparison to prior art assemblies. The CFD simulation results will be referenced below when describing certain aspects of the product overblow management assembly 102.

[0045] In the depicted exemplary embodiment, the product overblow management assembly 102 is generally defined by a deflector assembly having deflectors that are appropriately shaped, sized, and arranged to substantially prevent product from exiting the product handling zone 108. In addition, the deflector configuration is optimized to direct overblown product to an overblow landing area 146 defined between the product carrying units 106 and the heat exchanger assembly 114. In this manner, product overblow can be easily removed during cleaning as opposed to falling onto the evaporator coils 118.

[0046] Before discussing the particular embodiment shown, it should be understood that any suitable configuration and arrangement of deflectors can be used to achieve the desired result of substantially preventing product from exiting the product handling zone and directing any overblown product to an overblow landing assembly or another area that is easily cleaned (e.g., away from the evaporator coils). For example, the size of the deflectors can be lengthened, shortened, or otherwise adjusted to accommodate a larger or smaller gas handling system or a gas handling system having a different capacity. In addition, if an overblow landing assembly is defined in another area of the gas handling system, it should be understood that the configuration, size, and / or arrangement of the deflectors can be adapted to direct air to that overblow landing assembly. Thus, although a preferred exemplary embodiment is described herein, the product overblow management assembly 102 can be adapted for integration into other gas handling systems.

[0047] The product overblow management assembly 102 includes a first deflector assembly including a first tray side assembly and a second tray side assembly defined on a first side and a second side, respectively, of the product carrying units 106, where the first side of the product carrying units 106 is farthest from the heat exchanger assembly 114. Openings along the sides of the product carrying units 106 (e.g., at the intersection of the belt and tray sides) are not included. However, it should be understood that in some embodiments, such as in a gas handling system having a smaller or larger capacity, the openings can be included.

[0048] The first tray side assembly includes a substantially vertical first tray side 132 extending upwardly from a top surface of the product carrying units 106 to substantially prevent product from exiting the first side of the product carrying units 106 during processing. A first tray side extender 134 extends upwardly and outwardly (e.g., at an angle of approximately forty-five degrees (45°)) from the first tray side 132. The first tray side 132 and the first tray side extender 134 can be similar to prior art tray side designs as it is located on the first side of the product carrying units 106 that is farthest from the heat exchanger assembly 114. Thus, product overblow that exits the first side of the product carrying units 106 will not fall onto the heat exchanger assembly 114. In this regard, the first tray side 132 and the first tray side extender 134 can not necessarily be considered part of the product overblow management assembly 102, but can be used to maintain product in the product handling zone 108.

[0049] The second tray side assembly on the second side of the product carrying unit 106 (closest to the heat exchanger assembly 114) is generally configured to direct air upward away from the product handling area 108 and away from the heat exchanger assembly 114. In this regard, the second tray side assembly includes a substantially vertical second tray side 136 that extends upward from the top surface of the product carrying unit 106 for substantially preventing products from exiting the second side of the product carrying unit 106 during handling and directing air upward. The second tray side 136 can have substantially the same height as the first tray side 132, thereby defining a substantially rectangular product handling area 108 (e.g., the top surface of a conveyor belt, as Figure 7 illustrated, where the product handling area 108 generally defines a substantially rectangular "product bed").

[0050] The second tray side assembly also includes a second tray side extender 138 that extends upward and substantially inward from the second tray side 136 toward the central longitudinal axis of the product carrying unit 106. The second tray side extender 138 extends upward and inward from the second tray side 136 to direct the upward air flow substantially away from the heat exchanger assembly 114. For example, the inwardly extending second tray side extender 138 can be offset from the vertical direction by about ten to twenty degrees (10-20°). This angle can be increased or decreased depending on various factors, e.g., the width of the product carrying unit 106, the horizontal and / or vertical distance of the product carrying unit 106 from the heat exchanger assembly 114, the air flow rate through the product carrying unit 106, etc. In the depicted embodiment, the inwardly extending second tray side extender 138 can be offset from the vertical direction by about twelve to seventeen degrees (12-17°), e.g., about fifteen degrees (15°).

[0051] The height of the inwardly extending second tray side extender 138 is also such that it forces air flow to pass upward over the top end of the second tray side extender 138 before proceeding toward the heat exchanger assembly 114 for heat exchange, as Figure 6 illustrated. In the depicted embodiment, the top end of the second tray side extender 138 is generally above the top surface of the heat exchanger assembly 114. The height of the second tray side extender 138 can be increased or decreased depending on various factors, e.g., the width of the product carrying unit 106, the horizontal and / or vertical distance of the product carrying unit 106 from the heat exchanger assembly 114, the air flow rate through the product carrying unit 106, etc.

[0052] As noted above, the bypass mechanism can be used to reduce the air flow velocity through the product support unit 106 to fine tune the amount of fluidization of the product bed. In some embodiments, the bypass mechanism can be selectively opened to reduce the air flow velocity through the product support unit 106 to reduce or otherwise minimize product overblow. In other words, with lower air velocity through the product support unit 106, any product exiting the product handling zone 108 can necessarily have a lower velocity and can not reach the top end of the second tray side extender 138. Of course, any air flow adjustments are balanced with freezer performance.

[0053] The combination of the height and inward angle of the second tray side extender 138 substantially prevents product from exiting the product handling zone 108 (which can be understood to include the area in which the product bed is formed and the area extending upwardly from the product bed). Thus, the use of the product overblow management assembly 102 having the features described herein minimizes product overblow. At the same time, the height and inward angle of the second tray side extender 138 does not significantly impede air flow through the freezer. It can be appreciated that if the second tray side extender 138 used a significantly greater inward angle, product overblow could be eliminated entirely, but air flow resistance would increase and significantly impact freezer performance. Thus, the angle of the second tray side extender 138 is selected to minimize product overblow while minimizing air flow resistance as the air flows toward the heat exchanger assembly 114.

[0054] Air flows upwardly and through the second tray side extender 138 and toward the heat exchanger assembly 114 for cooling, as shown in Figure 6 In some cases, the product being processed will travel upwardly with the air and over the top end of the second tray side extender 138, resulting in product overblow. In this regard, the product overblow management assembly 102 also includes a second deflector assembly or overblow landing assembly (not separately labeled) that is configured to substantially direct overblown product to a desired area of the flow freezer 104 that is easy to clean (e.g., away from the evaporator coils 118 of the heat exchanger assembly 114), such as an overblow landing area 146.

[0055] In one aspect, the overblow landing assembly includes a resistance guide 139 defined at the top end of the second tray side extender 138 to help reduce the velocity of the overblown product as it travels over the top end of the second tray side extender 138, as shown in Figure 6The resistance guide 139 can be a generally curved configuration to direct the air upward and over the top of the second tray side extender 138 as the air travels toward the heat exchanger assembly 114. In the depicted exemplary embodiment, the resistance guide 139 is defined by a first flow resistance guide plate 140 that extends generally upward and away from the second tray side extender 138 and a second flow resistance guide plate 142 that extends generally laterally or horizontally from the first flow resistance guide plate 140. The first flow resistance guide plate 140 can extend away from the second tray side extender 138 (toward the heat exchanger assembly 114) at an angle of about thirty to fifty-five degrees (30-55°), such as about forty-five degrees (45°).

[0056] The first flow resistance guide plate 140 and the second flow resistance guide plate 142 can have generally the same length such that the upper tip of the second tray side assembly is substantially aligned with the second side of the product carrying unit 106 or is slightly offset from the second side of the product carrying unit 106 toward the heat exchanger assembly 114. Of course, the length of the first flow resistance guide plate 140 and / or the second flow resistance guide plate 142 can be adjusted to accommodate a smaller or larger distance between the product carrying unit 106 and the heat exchanger assembly 114, air flow variations, etc. Further, it should be appreciated that in some embodiments, the resistance guide 139 can instead be defined by a continuously curved surface or another suitable profile.

[0057] In another aspect, the over-blow landing assembly includes a redirection plate 144 that is configured to direct air flowing laterally over the resistance guide 139 and any over-blowing product generally downward to an over-blow landing area 146 defined between the product carrying unit 106 and the heat exchanger assembly 114. The redirection plate 144 is generally a vertically oriented plate that extends downward from an inner surface of a top panel of the flow freezer 104, defining a partial vertical partition in the freezer.

[0058] The redirection plate 144 is generally located about halfway between the horizontal position of the product carrying unit 106 and the horizontal position of the heat exchanger assembly 114. Further, the redirection plate 144 extends downward from the inner surface of the top panel a predetermined distance. In the depicted exemplary embodiment, the redirection plate 144 extends downward from the top panel of the freezer such that a lower or distal tip of the redirection plate 144 is at about the same vertical position as a distal end of the second flow resistance guide plate 142 and the top of the heat exchanger assembly. Of course, the length of the redirection plate 144 can be shorter or longer depending on various factors, such as the overall height of the freezer, the position of the heat exchanger assembly 114 relative to the product carrying unit 106, the air speed through the freezer, etc.

[0059] The position and length of the redirector plate 144 are designed such that air flowing laterally across the resistance guide 139 flows downward around the distal tip of the redirector plate 144 before flowing generally upward toward the heat exchanger assembly 114, as... Figure 6 As shown. In this respect, the redirector plate 144 typically changes the direction of airflow, turning the airflow approximately ninety degrees (90°) as it flows from the product carrier unit 106 to the heat exchanger assembly 114. More specifically, as air passes the resistance guide 139 and encounters the redirector plate 144, the air flows downward along the length of the redirector plate 144 until it reaches the distal end of the redirector plate 144. When the air reaches the distal end of the redirector plate 144, the airflow direction changes, turning approximately 90 degrees (90°) toward the heat exchanger assembly 114.

[0060] As the airflow direction changes, the airflow velocity near and / or close to redirector plate 144 increases (e.g., Figure 6 (As shown in Figure 162), while the air flowing below the high-speed air maintains a lower air velocity (e.g.) Figure 6 (As shown in low-to-medium speed air 164). This redirection of the airflow and the increase in velocity in high-speed air 162 help to separate any product overblown from the airflow (which flows to the heat exchanger assembly 114) and guide the overblown towards the overblown landing area 146 (see...). Figure 6 The arrows in the middle and Figure 8 (Particle regions 170 and 172 shown in the diagram). Furthermore, the redirection plate 144 physically prevents the overblown product from continuing along a lateral trajectory toward the heat exchanger assembly 114, thereby disrupting its momentum and allowing it to fall downwards into the flow of low-speed air 164, and then toward the overblown landing region 146.

[0061] The configuration of the overblown landing assembly (e.g., the relationship between the redirector plate 144 and the second tray-side extender 138 and the resistance guide 139) redirects airflow and increases the speed of product overblown separation without causing significant airflow resistance that would affect refrigeration performance. For example, through testing and CFD simulations, the inventors found that the total pressure loss caused by the product overblown management assembly 102 is approximately one hundred Pascals (100 Pa), where the total air pressure drop in an exemplary fluidized bed refrigeration unit is typically in the range of approximately nine hundred to one thousand nine hundred Pascals (900 Pa to 1900 Pa), depending on the product bed thickness, the amount of frost buildup on the evaporator coils or conveyors, etc. Therefore, the product overblown management assembly 102, including the overblown landing assembly, does not cause significant air resistance and therefore does not significantly affect refrigeration performance.

[0062] As described above, an overblow landing zone 146 can be defined between the product carrying unit 106 and the heat exchanger assembly 114. The overblow landing zone 146 can be defined by any suitable structure extending between the product carrying unit 106 and the heat exchanger assembly 144. For example, in the depicted exemplary embodiment, the overblow landing zone 146 is defined by a first overblow landing assembly plate 148 extending substantially laterally and slightly downwardly from the second tray side extender 138, a second overblow landing assembly plate 150 extending substantially laterally and downwardly from the first overblow landing assembly plate 148, and a third overblow landing assembly plate 152 extending substantially laterally and slightly downwardly from the second overblow landing assembly plate 150 until it intersects the substantially horizontal deck 124 of the heat exchanger frame 122.

[0063] From the foregoing, it will be appreciated that, given Figure 6 and Figure 8 , the product overblow management assembly 102 substantially prevents product from exiting the product handling zone 108. Moreover, the product overblow management assembly 102 is optimized to direct overblown product toward the overblow landing zone 146 away from the evaporator coils 118. Furthermore, the product overblow management assembly 102 reduces product overblow and directs any overblow to a safe zone without significantly impacting freezer performance.

[0064] In contrast, in the prior art design shown in the CFD simulation of Figure 7 and Figure 9 (in which like components are numbered identically except for the '200 series), a significant amount of product exits the product handling zone 208 and a significant amount of overblown product ends up on the evaporator coils 218. The prior art overblow assembly generally includes an outwardly sloped intermediate plate 240 positioned above and spaced apart from the second tray side extender 238. The outwardly sloped intermediate plate 240 includes a lower lateral flange 242 (with a downwardly turned lip 246) and an upper lateral flange 248. A vertical partition 244 extends downwardly from the freezer ceiling toward the upper end of the outwardly sloped intermediate plate 240. Thus, first and second air flow openings are defined between the first overblow landing assembly plate 249 extending substantially laterally and downwardly from the second tray side extender 238 and the lower lateral flange 242, and between the second tray side extender 238 and the vertical partition 244. Air flows through the first and second openings, allowing product to exit the product handling zone 208 and reach the evaporator coils 218.

[0065] Boundary conditions for the CFD simulation, including flow field comparisons and particle tracking, were generally as follows: - Each evaporator coil was replaced by an outlet condition.

[0066] - The vent, hatch, etc. of the bypass / pulsator assembly is replaced by an inlet to achieve a steady state approach.

[0067] - The product carrying unit and the food product on top of the product carrying unit are replaced by a region with momentum loss to simulate the pressure loss experienced by the cold air flowing through the product carrying unit.

[0068] The inputs for the CFD simulation are typically as follows: - Total air volume flow: 10.8 m 3 / s per fan (54 m 3 / s total) (all five fans and the prescribed velocity on the bypass hatch / pulsator).

[0069] - Bypass flow: 20% (10.8 m 3 / s total), evenly distributed over the bypass hatch and the pulsator.

[0070] - Prescribed outlet pressure on all outlets (evaporator coils).

[0071] - Air flow / average velocity through the belt: o Zone 1 (first conveyor belt 110a): 3.68 m / s.

[0072] o Zone 2 (second conveyor belt 110b): 3.57 m / s.

[0073] - Pressure drop over the first conveyor belt 110a and the second conveyor belt 110b and the food bed: ~ 600 Pa @ 1.2 kg / m 3 .

[0074] - Air is considered incompressible and isothermal (-20°C).

[0075] - Two-equation turbulence model k-w SST.

[0076] - Gravity influences the trajectory of the particles.

[0077] - Momentum loss in the lateral area around the belt (porous region).

[0078] Example A CFD analysis with particle tracking is performed on the product overblow management assembly 102 and the prior art design, with the results listed in the table at Figure 10 In the table at Figure 10 “New geometry” refers to the product overblow management assembly 102, while “Current geometry” refers to the Figure 7 and Figure 9The prior art overblow assembly design shown. The selected product / particle for analysis is a pea / husk. It is assumed that each pea is a spherical shape of constant diameter and density. In this regard, it is assumed that the drag force is that of a sphere, which depends entirely on the diameter. By calculating the diameter of the sphere and the total volume of multiple peas, the likelihood of multiple peas being frozen together is simulated. A maximum of four peas per group is tested.

[0079] The simulation includes the release of peas from the top surface of the belt (via air flow into the air) modeled using Lagrangian particle tracking. Since the conditions under which the peas take flight are not well defined, different parameters (e.g. different velocity gradients and directions) are tested. The likelihood of partially broken peas is modeled assuming the same diameter and volume but lower density (so broken peas have the same drag force but lower weight). Peas with densities of 40% and 20% of the reference pea are tested.

[0080] By calculating the thickness (0.05 mm), weight (assuming the same density as a pea) and surface area of the husk, the likelihood of the husk of a pea flying without the core is simulated. The diameter is also adjusted to account for the true surface of the entire husk and the likelihood of the husk splitting in two is considered.

[0081] It is assumed that particles interacting with the wall / plate / deflector do not bounce (100% restitution coefficient) but they essentially lose all their kinetic energy (about 95%). This assumption allows the air flow to accelerate the particles again in a direction that can bring them to the evaporator coil.

[0082] The analysis includes four tests (#4, #3, #2 and #1), each representing different initial velocities of the particles in the vertical and axial (lateral) directions. For example, for test #4, the initial velocity of the particles in the vertical direction is 8 m / s and the initial velocity of the particles in the axial direction is 2 m / s. For each test, the simulation results show whether the particles (one pea, one pea at 40% pea density, one pea at 20% pea density, single husk and double husk) exit the product handling zone (“complete the jump and land safely”) and, if so, whether they reach the evaporator coil (“reach the cooling battery area”).

[0083] According to Figure 10 As can be seen from the results in the table, the number of particles that exit the product handling zone is significantly reduced for the product overblow management assembly 102 described herein compared to the prior art design. Furthermore, none of the particles that exit the product handling zone reach the evaporator coil. In contrast, in the prior art design, a large number of particles exit the product handling zone and reach the evaporator coil 118.

[0084] Exemplary method Figure 11 is a flowchart of an example method 1100 for managing product overblow of a gas handling system configured to process a product by circulating a process gas from a heat exchanger assembly through a product carrying unit. The method 1100 can be performed using the product overblow management assembly 102 described herein incorporated into a suitable gas handling system, such as the flow freezer 104.

[0085] At step 1110, the method 1100 includes circulating the process gas from the heat exchanger toward the product carrying unit. For example, the process gas can be circulated in the flow freezer 104 from the heat exchanger assembly 114 toward the product carrying unit 106.

[0086] At step 1120, the method 1100 includes substantially preventing the product from exiting a product processing zone of the product carrying unit. For example, the first deflector assembly including the second tray side extender 138 can be used to substantially prevent the product from exiting the product processing zone 108 of the product carrying unit 106.

[0087] At step 1130, the method 1100 includes substantially directing the overblown product that has exited the product processing zone into an overblow landing area that is separate from the heat exchanger assembly. For example, the second deflector assembly including the redirection plate 144 can be used to substantially direct the overblown product that has exited the product processing zone 108 into the overblow landing area 146 that is separate from the heat exchanger assembly 114.

[0088] In an aspect, the method 1100 can include directing the airflow upward away from a product processing zone of the product carrying unit and inward toward a central longitudinal axis of the product carrying unit to substantially prevent the product from exiting the product processing zone of the product carrying unit. For example, the second tray side extender 138 can be used to direct the airflow upward away from the product processing zone 108 of the product carrying unit 106 and inward toward a central longitudinal axis of the product carrying unit to substantially prevent the product from exiting the product processing zone.

[0089] In an aspect, the method 1100 can include redirecting the airflow that exits the product processing zone of the product carrying unit substantially downward toward the overblow landing area. For example, the redirection plate 144 can redirect the airflow that exits the product processing zone 108 of the product carrying unit 106 substantially downward toward the overblow landing area 146.

[0090] In an aspect, the method 1100 can include increasing the airflow velocity when redirecting the airflow. For example, the velocity of the air flowing adjacent to and / or proximate to the redirection plate 144 increases (as represented by the arrows) as the air passes over the redirection plate 144 and the direction of the airflow changes. Figure 6indicated by arrows 166 and 168. The air flowing under the high velocity air 162 maintains a lower air velocity (as indicated by arrows 164) than the air flowing above the high velocity air 162. The air flowing under the high velocity air 162 is indicated by arrows 164. Figure 6 The turning of the air flow and the increase in velocity in the high velocity air 162 helps to separate any product overblow from the air flow (flowing toward the heat exchanger assembly 114) and direct the overblow toward the overblow landing area 146 (see Figure 6 The turning of the air flow and the increase in velocity in the high velocity air 162 helps to separate any product overblow from the air flow (flowing toward the heat exchanger assembly 114) and direct the overblow toward the overblow landing area 146 (see Figure 8 The turning of the air flow and the increase in velocity in the high velocity air 162 helps to separate any product overblow from the air flow (flowing toward the heat exchanger assembly 114) and direct the overblow toward the overblow landing area 146 (see

[0091] In an aspect, the method 1100 can include selectively opening at least one of the bypass mechanism and the pulsator. In an aspect, the method 1100 can include selectively opening the bypass mechanism to adjust the process gas velocity through the product carrying unit. For example, the bypass mechanism can be opened to reduce the air flow velocity through the product carrying unit 106 to fine tune the amount of fluidization of the product bed.

[0092] In an aspect, the method 1100 can include minimizing the pressure loss in the gas processing system to be within about one hundred Pascals (100 Pa). For example, employing the product overblow management assembly 102 described herein for the flow freezer 104 or similar gas processing system, product overblow is managed while only increasing the pressure loss of the gas processing system to be within about one hundred Pascals (100 Pa).

[0093] Various exemplary embodiments of the present disclosure are discussed in detail above. While specific implementations are discussed, it should be understood that these descriptions are included in illustrative embodiments only. Embodiments in accordance with the present disclosure can employ other components, configurations, and arrangements, without departing from the spirit and scope of the present disclosure. Accordingly, the specification and drawings are to be regarded in an illustrative rather than a restrictive sense.

[0094] Numerous specific details are set forth in this description in order to provide a thorough understanding. Flowever, in certain cases, well-known or conventional details are not described in order to not unnecessarily obscure the description. Reference throughout this patent document to "one embodiment," "an embodiment," or "the embodiment" means that a particular feature, structure, or characteristic described in connection with the embodiment is included in at least one embodiment. The appearances of the phrase "in one embodiment" in various places in the specification are not necessarily all referring to the same embodiment, nor are they necessarily all directed to the same embodiment, nor is the description necessarily exhaustive of any particular embodiment. Furthermore, descriptions of various features in

[0095] Reference to "one embodiment" or "an embodiment" means that a particular feature, structure, or characteristic described in connection with the embodiment is included in at least one embodiment of the disclosure. The appearances of the phrase "in one embodiment" in various places in the specification are not necessarily all referring to the same embodiment, nor are they necessarily all directed to the same embodiment, nor is the description necessarily exhaustive of any particular embodiment. Furthermore, descriptions of various features in

[0096] The terms used in this specification generally have their ordinary meanings in the art, within the context of the disclosure, and in the specific context where each term is used. Alternative language and synonyms can be used for any one or more of the terms discussed herein, and no special significance is to be placed upon whether or not a term is elaborately discussed herein. In some instances, synonyms for certain terms are provided. A recital of one or more synonyms does not exclude the use of other synonyms.

[0097] The use of examples anywhere in this specification, including examples of any terms discussed herein, is illustrative only, and in no way limits the scope and meaning of the disclosure or of any exemplified term. Likewise, the disclosure is not limited to various embodiments given in this specification.

[0098] The instruments, apparatus, methods, and articles of manufacture provided by the exemplary embodiments are presented by way of example only and are not intended to limit the scope of the disclosure. It should be noted that titles or subtitles can be used in the examples for convenience, but in no way should limit the scope of the disclosure. Unless otherwise defined, all technical and scientific terms used herein have the same meaning as commonly understood by one of ordinary skill in the art to which this disclosure belongs. In case of conflict between the legally determined meaning of terms and that used in the present document and its enclosed definitions, the legally determined meaning takes precedence.

[0099] Additional features and advantages of the disclosure are set forth in the description, which makes apparent to those skilled in the art that some features and advantages can be derived from the description, or can be appreciated by practice of the techniques disclosed herein. Features and advantages of the present disclosure can be realized and obtained by means of the instruments and combinations particularly pointed out in the appended claims.

[0100] For the sake of clarity, the technology can be presented in some embodiments in the form of a process, which comprises independent functional blocks coupled via one or more data signals. These blocks represent modules, segments, or codes of the software implemented as programs in the internal memory, discrete hardware components, or any combination thereof. For the sake of clarity, the data signals are represented by means of arrows in the drawings.

[0101] In the drawings, some structural or methodological features can be shown in a particular arrangement and / or order. However, it should be understood that such a particular arrangement and / or order can not be required. Rather, in some embodiments, such features can be arranged differently and / or in a different order than shown in the illustrative drawings. Additionally, inclusion of a structural or methodological feature in a particular drawing does not imply that such a feature is required in all embodiments, as it can be excluded or combined with other features in some embodiments.

[0102] While the technical solutions of the present disclosure allow various modifications and alternative forms, specific embodiments thereof have been shown by way of example in the accompanying drawings and will be described in detail herein. It should be understood, however, that the present disclosure is not intended to be limited to the particular forms disclosed, but on the contrary, it is intended to cover all modifications, equivalents, and alternatives falling within the scope of the present disclosure and the appended claims.

[0103] While the illustrative embodiments have been described with respect to a limited number of embodiments, it will be appreciated that many variations, modifications and other applications of the present application can be made within the scope of the detailed teachings and inherent to this disclosure and following claims.

Claims

1. A product overblow management assembly for a gas processing system configured to process a product by circulating a process gas from a heat exchanger assembly through a product carrying unit, the product overblow management assembly comprising: a first deflector assembly configured to substantially prevent product from exiting a product processing zone of the product carrying unit; and a second deflector assembly configured to substantially direct overblown product that has exited the product processing zone into an overblow landing area that is separate from the heat exchanger assembly.

2. The product overblow management assembly of claim 1, wherein, The first deflector assembly includes a first tray side extending upward from a first side of the product carrying unit, a second tray side extending upward from a second side of the product carrying unit, and a tray side extender extending upward from the second tray side toward a longitudinal center axis of the product carrying unit.

3. The product overblow management assembly of claim 2, wherein, A distal end of the tray side extender is located above the heat exchanger assembly.

4. The product overblow management assembly of claim 2, wherein, The tray side extender is offset from vertical at an angle of about ten to twenty degrees (10°-20°).

5. The product overblow management assembly of claim 2, wherein, The second deflector assembly includes a drag directing assembly defined at the distal end of the tray side extender, the drag directing assembly configured to reduce air drag as air flows upward and over the distal end of the tray side extender.

6. The product overblow management assembly of claim 2, wherein, The second deflector assembly includes a redirecting plate extending substantially vertically downward from an interior upper surface of the gas processing system, the redirecting plate configured to redirect air and overblown product that flows over the tray side extender substantially downward toward the overblow landing area.

7. The product overblow management assembly of claim 6, wherein, The redirecting plate is located approximately halfway between a horizontal location of the product carrying unit and a horizontal location of the heat exchanger assembly.

8. The product overblow management assembly of claim 6, wherein, The redirecting plate extends downward from the interior upper surface of the gas processing system such that a vertical location of a distal tip of the redirecting plate is below an upper end of the first deflector assembly and above a top surface of the heat exchanger assembly.

9. The product overblow management assembly of claim 6, wherein, As air passes through the distal tip of the redirecting plate, a velocity of air flow proximate the redirecting plate increases to aid in separating product overblow from the air flow and directing the product overblow toward the overblow landing area.

10. The product overblow management assembly of claim 1, wherein, The overblow landing area is defined between the product carrying unit and the heat exchanger assembly.

11. The product overblow management assembly of claim 1, further comprising a bypass assembly configured to selectively open to adjust a process gas velocity through the product carrying unit.

12. The product overblow management assembly of claim 1, wherein, The product processing zone includes an area in which a product bed is formed and an area extending upward from the product bed.

13. A gas processing system comprising: a housing; a heat exchanger assembly; a gas circulation assembly for circulating a process gas within the housing; a product carrying unit configured to support a product to be processed with the process gas, the process gas being circulated within the housing and upward through the product carrying unit; and a product overblow management assembly comprising: a first deflector assembly configured to substantially prevent product from exiting a product processing zone of the product carrying unit; and a second deflector assembly configured to substantially direct overblown product that has exited the product processing zone into an overblow landing area that is separate from the heat exchanger assembly. a second deflector assembly configured to substantially direct overblown product that has exited the product processing zone of the product carrying unit into an overblown landing area that is separate from the heat exchanger assembly.

14. The system of claim 13, wherein, the first deflector assembly includes a first tray side extending upwardly from a first side of the product carrying unit, a second tray side extending upwardly from a second side of the product carrying unit, and a tray side extender extending upwardly from the second tray side toward a longitudinal center axis of the product carrying unit.

15. The system of claim 14, wherein, the second deflector assembly includes a redirecting plate extending substantially vertically downwardly from an interior upper surface of the housing, the redirecting plate configured to redirect air and overblown product flowing through the tray side extender substantially downwardly toward the overblown landing area.

16. The system of claim 15, wherein, the redirecting plate is located approximately halfway between a horizontal location of the product carrying unit and a horizontal location of the heat exchanger assembly.

17. The system of claim 15, wherein, the redirecting plate extends downwardly from the interior upper surface of the housing such that a vertical location of a distal tip of the redirecting plate is below an upper end of the first deflector assembly and above a top surface of the heat exchanger assembly.

18. The system of claim 15, wherein, as air passes through the distal tip of the redirecting plate, a velocity of air flow proximate to the redirecting plate increases to aid in separating product overblow from the air flow and directing the product overblow toward the overblown landing area.

19. The system of claim 13, wherein, the gas circulation assembly is located approximately below the product carrying unit and between the heat exchanger assembly and the product carrying unit.

20. A method of managing product overblow of a gas processing system configured to process product by circulating processing gas from a heat exchanger assembly through a product carrying unit, the method comprising: circulating processing gas from a heat exchanger toward the product carrying unit; substantially preventing product from exiting a product processing zone of the product carrying unit; and substantially directing overblown product that has exited the product processing zone into an overblown landing area that is separate from the heat exchanger assembly.

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