Transportable container, loader system, method, and kit for generating carbon dioxide snow blocks in situ within a transportable container for preservation of items stored therein

Abstract

To provide a novel kit, transportable device, and method for on-site generation of CO2 snow blocks within a device. [Solution] Articles such as biological samples can be stored and transported within the same device employed to create CO2 snow blocks. The device allows for the preservation of samples during transport. The present invention also includes a specially designed CO2 snow filler system that includes a filler and mesh conduit 3. The filler system is operated according to the method of the present invention to create in situ CO2 snow blocks within a container 2 that can also be used for transportation.

Description

[Technical Field]

[0001] The present invention relates to a unique device, filler system, method, and kit for in situ generation of blocks of carbon dioxide (hereinafter "CO") snow within containers that can be used to store and transport a variety of items, including biological specimens. [Background technology]

[0002] Drug development remains a major endeavor in the pharmaceutical industry. Drug development requires clinical trials to establish the safety and effectiveness of new treatments. Today, many clinical trials in various stages are underway in the United States, a country. Each clinical trial may involve hundreds to thousands of patients who volunteer to receive an experimental drug. Typically, as part of a clinical trial, biological samples (e.g., tissue, urine, blood samples) are collected from participants at a clinical site, such as a hospital, university, or medical institution, and then transported to a laboratory for analysis or to a facility where they can be frozen and stored for later analysis.

[0003] The ability to evaluate the safety and efficacy of investigational pharmaceuticals requires obtaining reproducible and reliable results during clinical trials. Biological samples must be stable and preserved during storage and transport, for example, between clinics and laboratories. Today, a common means of preserving biological samples is by freezing and storing them in the presence of solid carbon dioxide (i.e., dry ice).

[0004] Dry ice systems typically involve manually loading samples and dry ice into an insulated box, such as a polystyrene box, at the clinical site where the sample is obtained. Dry ice is typically provided to clinical sites by pharmaceutical companies or contract research organizations. The insulated box components may be provided assembled or disassembled. Assembling the insulated box and loading it with dry ice can be labor-intensive. There can also be significant costs and inconveniences associated with maintaining an adequate supply of dry ice at the clinical site. Additionally, failure to use such dry ice for a limited time can result in the loss of its cooling effectiveness. Furthermore, insulated boxes are typically not reusable and must be discarded, resulting in waste.

[0005] Other drawbacks also exist when transporting samples in traditional insulated boxes. Dry ice cools the interior of the insulated box by sublimating carbon dioxide vapor. Many insulated boxes are available that can maintain low internal temperatures for various durations, up to four or five days. Although the internal sample space may be uniformly close to the dry ice temperature when initially loaded with all the dry ice, as the dry ice sublimes, large temperature gradients can develop within the internal sample space, potentially reducing sample quality. Insulated boxes are generally shipped via expedited delivery methods to ensure that a sufficiently low temperature is maintained within the internal sample space. However, if delays or disruptions occur in shipping lanes, samples may be subject to degradation. Such delays during shipping may result in the need to load additional dry ice into the box during transport, increasing shipping costs and logistical complexity.

[0006] One alternative to traditional dry ice shipping containers is a cryogenic liquid nitrogen-based vapor container. Cryogenic liquid nitrogen-based vapor containers utilize an absorbent to maintain cryogenic nitrogen in a vapor state and avoid the presence of nitrogen in liquid form. However, such liquid nitrogen-based vapor containers suffer from drawbacks. One drawback is the time and labor involved in preparing the container. Specifically, users prepare such containers by spraying liquid nitrogen into the container and waiting several hours for sufficient absorption of the nitrogen on the absorbent, followed by gently decanting excess liquid nitrogen before shipping. Substantial handling of cryogenic liquid nitrogen is required, and significant time is required to prepare the liquid nitrogen shipping container prior to use. Furthermore, the costs associated with using liquid nitrogen-based vapor containers are significantly higher than alternative dry ice containers.

[0007] In view of these shortcomings, there is an unmet need for improved methods for preserving samples in containers during storage and transport. Summary of the Invention

[0008] In one aspect, a carbon dioxide (CO2) snow making kit for charging CO2 in situ within a container and generating CO2 snow blocks includes a container including an interior volume defined by a first region and a second region, the first region being an interior mesh conduit volume and the second region being a snow chamber within which the CO2 snow blocks are generated and stored, the interior volume being further surrounded by a plurality of container walls; an interior mesh conduit configured to receive the mesh conduit; a snow chamber surrounding an exterior surface of the mesh conduit and at least partially enclosed by the plurality of container walls; and a mesh conduit located within an opening of the container and extending into the interior mesh conduit volume, allowing gas to pass through but not allowing the CO2 snow blocks to be stored within the mesh conduit volume. a mesh conduit having openings porous enough to allow CO2 off-gas to substantially remain within a snow chamber external to the mesh conduit, the mesh conduit further including an internal passage for venting CO2 off-gas, the mesh conduit having a first end and a second end, the first end oriented toward the opening of the container; and a CO2 snow charger operatively or integrally connected to the first end of the mesh conduit along the opening of the container, the CO2 snow charger comprising a conduit network having a plurality of nozzles configured to selectively direct CO2 fluid into the snow chamber while substantially preventing CO2 fluid from being introduced into the internal passage of the mesh conduit, the snow charger further comprising one or more openings in fluid communication with the internal passage of the mesh conduit, the one or more openings and a CO2 snow filler, the mouth of which is configured to allow gas to be vented through the opening and exit the container.

[0009] In a second aspect, a method for in situ generation of carbon dioxide (CO2) snow blocks within a transportable container includes the steps of supplying CO2 liquid to a CO2 snow charger operably or integrally connected to a mesh conduit positioned within the interior of an insulated transportable container, introducing the CO2 liquid into a nozzle of a conduit network of the CO2 snow charger, selectively directing the CO2 fluid into a snow chamber of the container outside the mesh conduit, generating CO2 snow particles and gas in situ in the snow chamber, compressing the CO2 snow particles to form a substantially block of CO2 snow characterized by hollow passages along the block of CO2 snow, passing the gas through the mesh conduit, venting the gas along the inner passages of the mesh conduit, and removing the gas through the CO2 snow charger.

[0010] In a third aspect, a method for assembling a carbon dioxide (CO2) snow filling system on-site for in-situ generation of CO2 snow blocks in a container includes providing a liquid CO2 source; providing an insulated container with an opening, the container further comprising an interior volume defined into a first region and a second region, the first region being an inner mesh conduit volume and the second region being a snow chamber; providing a mesh conduit; an inlet opening for receiving the liquid CO2 source; and a plurality of nozzles distributed along an edge of the conduit. The method includes providing a CO2 snow filler having a conduit network having a mesh conduit, the CO2 snow filler further having one or more exhaust openings for exhausting gas from the filler; operably connecting or integrally joining a lower section of the CO2 snow filler to an upper section of a mesh conduit; inserting the mesh conduit into an inner mesh conduit volume through an upper opening of a container; fixing an upper portion of the mesh conduit to the container at the upper opening of the container; and operably connecting an inlet opening of the CO2 snow filler to a CO2 source.

[0011] In a fourth aspect, a carbon dioxide (CO2) snow filler system adapted to produce CO2 snow blocks comprises: a mesh conduit having porous openings sufficient to allow CO2 off-gas to pass through the openings and enter an inner passage of the mesh conduit but substantially block the ingress of particles from the CO2 snow block into the inner passage, and characterized by sufficient rigidity to compress CO2 snow blocks generated outside the mesh conduit; and a CO2 snow filler operably or integrally connected to the mesh conduit, the CO2 snow filler comprising a conduit network with a plurality of nozzles configured to selectively direct CO2 fluid to the outside of the mesh conduit while substantially preventing the introduction of CO2 liquid into the inner passage of the mesh conduit, the snow filler further comprising one or more exhaust openings in fluid communication with the inner passage of the mesh conduit, the one or more exhaust openings configured to allow gas to be vented through the openings.

[0012] In a fifth aspect, an apparatus configured for storing, preserving, and transporting one or more items includes a transportable container having a cylindrical shape, the container having an interior volume defined in a first region and a second region, the first region being an inner product storage volume and the second region being a snow chamber in which CO2 snow is stored, the container further comprising a plurality of insulated container walls at least partially surrounding the first region and the second region, the walls comprising a getter material positioned within the walls, the getter material maintaining a vacuum and insulation level and suitable for compatibility with the CO2 snow; an inner product storage volume defined by a mesh conduit, the mesh conduit being permanently or removably affixed to one or more insulated container walls; and a snow chamber surrounding an exterior of the mesh conduit. The snow chamber comprises a snow chamber partially surrounded by a plurality of vacuum insulated container walls; CO2 snow occupying the interior of the snow chamber; and a mesh-like conduit having a first end and a second end, the first end oriented toward an opening of the transportable container, wherein the snow chamber is characterized by a lack of foam filler material or absorbent material.

[0013] In a sixth aspect, a method for assembling a carbon dioxide (CO2) snow filling system on-site for in-situ generation of CO2 snow blocks in a container includes providing a CO2 source; providing an insulated container with an opening, the container further comprising an interior volume defined into a first region and a second region, the first region being an inner mesh conduit volume and the second region being a snow chamber; providing a mesh conduit operably connected or integrally connected to the insulated container; providing a CO2 snow filler comprising a conduit network having an inlet opening for receiving the CO2 source and a plurality of nozzles distributed along an edge of the conduit, the CO2 snow filler further comprising one or more exhaust openings for gas to be exhausted from the filler; attaching the CO2 snow filler to the container; fixing an upper portion of the mesh conduit to the CO2 snow filler at the upper opening of the container; and operably connecting the inlet opening of the CO2 snow filler to the CO2 source. [Brief explanation of the drawings]

[0014] [Figure 1a] 1a shows a cross-sectional view taken along line 1a-1a of FIG. 1b showing a kit for filling a shipping container with CO2 snow. [Figure 1b] FIG. 1b shows a top view of the CO2 snow charger used in the kit of FIG. 1a. [Figure 2] 1 shows a CO2 snow charging system including a mesh conduit and a CO2 snow charger. [Figure 3a]3a shows an alternative CO2 snow filling system in a cross-sectional view taken along line 3a-3a of FIG. 3b, with the snow filling system having an H-shaped conduit flow network. [Figure 3b] 3b shows a top view of a snow filler used in the CO2 snow filling system of FIG. 3a. [Figure 4a] 4a shows an alternative CO2 snow filling system in a cross-sectional view taken along line 4a-4a of FIG. 4b, with the snow filling system having a cross-sectional shaped conduit flow network. [Figure 4b] 4a shows a top view of a CO2 snow charger used in the CO2 snow charging system of FIG. 4a. [Figure 5] 1 shows a representative CO2 filling station in a perspective view with a transportable container assembled and connected to a ventilation system and a liquid CO2 source. [Figure 6] 1 shows a cross-sectional view of a top cover with a mechanical seal inserted into a transportable container for use during transport of the container and items within a mesh conduit within the container. [Figure 7a] 1 shows an alternative design of a CO2 snow charger kit used to generate in-situ CO2 snow within a standard shipping box. [Figure 7b] 1 shows an alternative design of a CO2 snow charger kit used to generate in-situ CO2 snow within a standard shipping box. [Figure 8] 1 shows a comparison of the temperature profile of a storage device of the present invention containing CO2 snow blocks prepared by the method of the present invention and a standard shipping container filled with CO2 dry ice pellets. [Figure 9] A standard shipping box is shown. [Figure 10] 1 illustrates a process flow for introducing CO2 gas and CO2 liquid from a CO2 source into a transportable container in accordance with the principles of the present invention. [Figure 11]1 shows the temperature profile for a storage device of the present invention containing CO2 snow blocks filled into a container by the method of the present invention, the walls of the container being vacuum insulated to a vacuum level of approximately 10 microns. DETAILED DESCRIPTION OF THE INVENTION

[0015] As described, in one aspect, the present invention proposes a system and method for generating in situ CO2 snow blocks from a CO2 source directly within a specially designed, transportable container, preferably using an automated filling system. In this way, there is no need to transfer CO2 snow or dry ice from a separate production container to the transportable container, thereby reducing the labor required to load the CO2 snow or dry ice into a cryogenic shipping vessel. On-demand generation eliminates the need for users to maintain an inventory of CO2 snow blocks or dry ice on-site. The automation of the process simplifies operation, thereby making the system accessible to any user. While the present invention can be used with any "article," as defined below, in preferred embodiments, the present invention is particularly conducive to maintaining compliance with packaging protocols necessary to reproducibly preserve biological samples, thereby avoiding sample degradation and enabling the samples to be restored to their original functional state and undergo appropriate testing upon arrival at their destination. Furthermore, the in situ CO2 snow blocks are preferably generated with improved packing density, which allows the container to maintain the required temperature for an extended cooling effect, compared to standard dry ice shipping containers containing CO2 dry ice manufactured by conventional techniques. The extended duration of the cooling effect can reduce the risk of sample degradation during transport and allows users more flexibility to optimize the cost and convenience of preparing and assembling the transportable containers of the present invention, the timing of acquiring items (including samples such as biological samples), and the type of shipping method available.

[0016] It should be understood that the terms "CO2 snow" and "dry ice" have the same meaning and may be used interchangeably herein and throughout to refer to particles of solidified CO2.

[0017] "CO2 snow block" or "CO2 block," both of which may be used interchangeably herein and throughout, are intended to refer to the creation of CO2 snow particles in substantially block-like form of any shape consisting of tightly held particles.

[0018] As used herein, "CO2 fluid" means any phase, including liquid, gas, vapor, supercritical, or any combination thereof.

[0019] As used herein, a "CO2 source" or "liquid CO2 source" includes, but is not limited to, a cylinder, a dewar, a bottle, and a bulk or microbulk tank.

[0020] As used herein, "conduit" or "conduit flow network" means tubes, pipes, hoses, manifolds, and any other suitable structures sufficient to create one or more flow paths and / or allow the passage of fluids.

[0021] As used herein, "connected" or "operably connected" means a direct or indirect connection between two or more components such as conventional piping and assemblies, including, but not limited to, valves and conduits, that allow for fluid, mechanical, chemical, and / or electrical communication between the two or more components, unless otherwise specified.

[0022] As used herein, "item" refers to any item that is not frozen or maintained below a certain temperature, including, but not limited to, biological samples such as blood, urine, tissue samples, or components thereof; perishable foods such as meat, poultry, fish, and dairy products; personal care items; and chemicals. "Temperature-sensitive" means any temperature-sensitive item, product, or supply that is subject to spoilage, deterioration, and / or structural change or denaturation in the event of spoilage.

[0023] As used herein, "filling" refers to the process of introducing CO2 fluid from an external CO2 source into a container operably connected to the external CO2 source.

[0024] "Transportable" means a device that is capable of being moved, transported, or shipped from a user's location to another destination by any known means, including, but not limited to, air, ground, or sea. Transportation or shipping may occur through various package delivery services, including, but not limited to, parcel post, UPS® shipping services, FedEx® shipping services, etc.

[0025] The embodiments as described below are merely examples, and the present invention is not limited to the embodiments illustrated in the drawings. It should also be understood that the drawings are not to scale and that in some cases details not necessary for understanding the embodiments, such as conventional manufacturing and assembly details, have been omitted.

[0026] The embodiments are described with reference to the drawings, in which like elements are referenced by like numerals. The relationship and function of the various elements of the embodiments will be better understood from the detailed description that follows. The Detailed Description contemplates various permutations and combinations of features, aspects, and embodiments as being within the scope of the present disclosure. Accordingly, the present disclosure may be specified to comprise, consist of, or consist essentially of any or selected one or more of such combinations and permutations of these specific features, aspects, and embodiments.

[0027] In one embodiment of the present invention, FIG. 1a illustrates a suitable CO2 snow making kit 1 for filling a transportable container 2 with CO2 fluid and generating CO2 snow blocks in situ. Kit 1 preferably includes a transportable container 2, a mesh conduit 3, and a CO2 snow filler 4. Transportable container 2 preferably includes multiple walls, which are preferably insulated along a substantial portion thereof by an insulated bottom wall 5, an insulated side wall 6, and an insulated top cover, which is positioned over an opening 7 of container 2 during transport. Preferably, walls 5 and 6 are vacuum insulated to a certain level. Container 2 is preferably cylindrical to enhance the ability to generate an enhanced vacuum within walls 5 and 6. A suitable getter material, corresponding to CO2 snow or CO2 snow blocks, may occupy the space within vacuum-insulated walls 5 and / or 6. Due to its sorption capabilities, the getter material acts as a pump to increase the vacuum level within walls 5 and / or 6. When kit 1 is assembled, container 2 has an opening 7 into which mesh conduit 3 can be inserted. The lower section of the snow filler 4 is connected (e.g., via welding, mechanical fastening, etc.) to the first end 17 of the mesh conduit 3, creating a seal at the attachment point. Alternatively, the snow filler 4 and mesh conduit 3 can be integrally connected by being manufactured as a single filler component.

[0028] The transportable container 2 includes an interior volume that can be divided into a first region and a second region. The first region is the inner mesh conduit volume within which the mesh conduit 3 can be located. The mesh conduit volume can be any suitable volume. In one embodiment, the mesh conduit volume is greater than about 25 L, preferably up to about 10 L, and more preferably up to about 3 L. In another embodiment, the mesh conduit volume is in the range of 0.25-25 L, preferably 0.25-10 L, and more preferably 0.25-1 L. The second region is the snow chamber 11 within which the CO2 snow block 10 is generated and stored. The snow chamber 11 preferably surrounds the mesh conduit 3, and the snow chamber 11 is configured to accommodate the container. The chamber is completely or substantially insulated along all sides of the chamber 2. It should be understood that a relatively small portion of the insulating walls 5 and / or 6 may be removed to create an opening 7 to ensure proper CO2 fluid filling and sample loading, as described herein below.

[0029] The mesh conduit 3 includes an inner passageway 14. The mesh conduit 3 is preferably tubular, although it should be understood that other shapes are contemplated. The mesh conduit 3 is inserted through an opening 7 of the container 2 and extends into the container's inner mesh conduit volume. The mesh conduit has a first end 17 and a second end 18. The first end 17 is oriented toward the opening 7 of the container 2, and the second end 18 is preferably oriented toward the vacuum insulated bottom wall 5. In a preferred embodiment, when inserted into the container 2, the mesh conduit 3 is symmetrically disposed along the longitudinal central axis of the container 2 to create a substantially uniform space between the outer surface of the mesh conduit 3 and the vacuum insulated side wall 6, thereby creating a symmetrical annular snow chamber 11 that allows the CO2 snow block 10 to be fabricated within the chamber 11 as a symmetrical annular substantially block-shaped block.

[0030] The mesh conduit 3 includes openings 16 on the surface of the conduit 3, as can be seen more clearly in Figure 2. The inventors have discovered that utilizing the mesh conduit 3 provides resistance that contributes to the compression of snow particles generated within the snow chamber 11, thereby creating the CO2 snow block 10. The CO2 snow block 10 can have a higher compressed density than would otherwise be produced without the mesh conduit 3 located within the container 2. In one embodiment, the CO2 snow block 10 produced with the mesh conduit 3 and method of the present invention has a bulk density comparable to that of pelletized dry ice CO2.

[0031] Openings 16 in mesh conduit 3 allow CO2 off-gas ("GCO2" in FIG. 1a) produced from the generation of CO2 snow particles to pass through openings 16 and enter inner passage 14 of mesh conduit 3. Once in inner passage 14, the CO2 off-gas can flow along it, as shown by the upward arrow in FIG. 1a, and then flow through one or more openings 13 in snow filler 4 (FIG. 1b) to exit container 2. The CO2 off-gas can then be vented to a vent system that may be connected to container 2.

[0032] A snow chamber 11 surrounds the exterior of the mesh conduit 3. Contrary to cryogenic liquid nitrogen shipping containers, the snow chamber 11 is characterized by a lack of foam fill material or absorbent material. The snow chamber 11 is surrounded by a vacuum insulated bottom wall 5 and a vacuum insulated side wall 6.

[0033] A top view of the snow charger 4 corresponding to FIG. 1a is shown in FIG. 1b. The snow charger 4 includes a cross-shaped conduit flow network 8, a ring tube 19 with nozzles 12 distributed along the ring tube 19 and extending along the edge of the network 8, and an outer sleeve 9 surrounding the ring tube 19. A central opening 15 is provided into which CO2 fluid enters from a CO2 source. Four nozzles 12 are uniformly distributed along the ring tube 19 of the cross-shaped conduit flow network 8 to ensure uniform injection of CO2 fluid into the snow chamber 11. The conduit flow network 8 is connected to the ring tube 19. Each nozzle 12 is spaced approximately 90 degrees from the others, and each nozzle 12 has an opening of the same size. The conduit flow network 8 creates a symmetrical cross-shaped structure that creates uniform openings 13 for CO2 off-gas to vent from the inner passages 14 of the mesh conduit 3. Such a configuration of the impregnator 4 creates a substantially uniform flow of CO2 fluid through the nozzles 12, creating a substantially uniform formation and distribution of CO2 snow blocks 10 within the chamber 11. The introduction of CO2 fluid into the snow impregnator 4 is indicated by the downward dotted lines in FIG. 1a extending toward the central opening 15, and the distribution of CO2 fluid within the conduit flow network 8 is indicated by the horizontal dotted lines in FIG. 1a extending toward the nozzles 12. The introduction of CO2 fluid from the nozzles 12 is indicated by angled downward arrows into the snow chamber 11. In one embodiment, referring to FIG. 1a, the nozzles 12 can be oriented away from the vertical wall of the mesh conduit at an angle ranging from approximately 30° to 60° relative to the vertical wall, such that the vertical wall extends perpendicular to the horizontal surface of the container 2. Other angular configurations of the nozzles 12 are contemplated. The flow path of the CO2 off-gas is indicated by the upward dotted lines in FIG. 1a, labeled "GCO2," within the inner passage 14 of the mesh conduit 3.

[0034] It should be understood that the present invention contemplates other shapes of nozzles 12, central opening 15, and conduit flow network 8, other geometric patterns for conduit flow network 8 (e.g., H-shaped or T-shaped), and other distributions and locations of nozzles 12 along conduit flow network 8. As an example, FIGS. 3a and 3b show an alternative snow filling system 300, which corresponds to container 2 of FIGS. 1a and 1b. System 300 includes mesh conduits or tubes 303 and snow filler 304. Snow filler 304 has an H-shaped conduit flow network 306. As shown in FIGS. 3a and 3b, nozzle 301 is positioned along the tapered portion where sleeve 302 and H-shaped conduit flow network 306 connect. A central opening 305 of H-shaped conduit flow network 306 can receive a supply of CO2 fluid from a CO2 source. The CO2 fluid is then directed through an H-shaped conduit flow network 306 into a nozzle 301 that directs the CO2 fluid into the snow chamber 11 angled toward the insulating wall 6 while substantially avoiding introduction of the CO2 fluid into the mesh tubes 303. The CO2 fluid preferably enters the snow chamber 11 as a liquid.

[0035] Opening 307 is in fluid communication with the inner passage of mesh tubing 303 to allow CO2 off-gas generated from in-situ snow block 10 to vent through the opening. Snow filling system 300 can be inserted into a preferably cylindrically shaped container, such as container 2 of FIG. 1 a, to form a kit suitable for in-situ manufacturing of snow blocks within a cylindrically shaped container.

[0036] 4a and 4b show an alternative snow filling system 400, which also corresponds to the container 2 of FIGS. 1a and 1b. The system 400 includes a different design for the conduit flow network 406 and sleeve 402. The sleeve 402 of the de-filler 404 is designed to fit the shape of the container 2. As with the other filling systems of the present invention, the sleeve 402 provides a sufficient seal during the CO2 snow filling operation. The sealing effect of the sleeve 402 prevents CO2 off-gas from exiting the container 2 except through the opening 407 in the snow filler 404. FIG. 4a shows that the CO2 fluid inlet conduit (i.e., the flow network conduit 406) passes through the sleeve 402. A nozzle 401 is configured at the tip of the conduit flow network 406 and can be opened in a direction as needed to inject CO2 fluid into the snow chamber 11 of the container 2. The CO2 fluid, preferably in a liquid phase, enters the holes 405 and then flows laterally down each side of the conduit flow network 406. The CO2 fluid then flows downward along conduit flow network 406 where it flows through nozzles 401 located along the sides of mesh tubes 403 and then into snow chamber 11 of container 2. FIG. 4a shows that the side portions of mesh conduit 403 are attached to sleeves 402. The charging and discharging system 400 can be inserted into a container, such as cylindrical container 2 of FIG. 1a, in accordance with the principles of the present invention, to form a kit 1 capable of in-situ fabrication of CO2 snow blocks within cylindrical container 2.

[0037] As can be seen, conduit flow networks 306 and 406 represent different structural configurations intended to achieve specific flow patterns of CO2 fluid through the flow networks, which are directed into snow chamber 11 of container 2. It should be understood that the snow filling systems of the present invention, including filling system 300 and filling system 400, can be utilized with other containers, aside from container 2 of FIG. 1a.

[0038] The exact selection of the geometry and overall design of the filler, such as the examples shown in the designs of filler 4, filler 304, and filler 404, may be based on several design factors, including, but not limited to, the internal volume of container 2 (i.e., the volume of mesh conduit 3 and / or the volume of snow chamber 11) and the amount of CO2 snow block 10 that needs to be generated to maintain the storage of items, such as biological samples, that are stored during transport at a temperature below a predetermined temperature for a certain duration (e.g., approximately 4 days at or below -60°C).

[0039] 1a, 1b, and 2, it can be seen that the effective diameter of the snow charger 4 is wider than the diameter of the mesh conduit 3 to ensure that nozzles 12, positioned along the edge or periphery of the conduit flow network 8, introduce CO2 fluid outside the mesh conduit 3 into the snow chamber 11 while substantially avoiding injection of CO2 fluid into the inner passages 14 of the mesh conduit 3. A substantial portion of the CO2 snow particles formed in the snow chamber 11 do not pass through the inner passages 14, which are designed solely to allow CO2 off-gas generated during the formation of the CO2 snow blocks 10 to flow therethrough, thereby allowing the CO2 off-gas to be removed from the transportable container 2. In this regard, the angled arrows pointing to the snow chamber 11 in FIG. 1a are intended to indicate the location of the nozzles 12 and the corresponding introduction of CO2 fluid into the snow chamber 11 through the nozzles 12.

[0040] 1a, 1b, and 2, a sleeve 9 extends around the conduit flow network 8. The sleeve 9 can extend further away from the snow charger 4 and be attached to the container 2 by any suitable means, as shown in FIG. 1a, thereby securing the charger 4 and mesh conduit 3 in a stationary position during operation of the kit 1. In one embodiment, as shown in FIG. 1a, the sleeve 9, which is part of the charger 4, extends vertically away from the top of the charger 4 and attaches along an upper section of the container 2. The sleeve 9 can provide structural reinforcement for the mesh conduit 3. The ability to reinforce the mesh conduit 3 allows the mesh conduit 3 to provide greater resistance to CO2 snow blocks 10 that form and accumulate within the snow chamber 11. As a result, the present invention can provide the benefits of in-situ fabrication of dense CO2 snow blocks 10 and increased payload capacity of CO2 snow blocks 10 within the snow chamber 11, compared to CO2 snow created in a container without a mesh conduit.

[0041] The sleeve 9 also acts as a seal, preventing the CO2 off-gas from exiting the container 2 other than through the opening 13 in the snow filler 4. Venting of the CO2 off-gas through the opening 13 can only occur when the CO2 off-gas flows within the inner passage 14 of the mesh conduit 3. In this manner, the sleeve 9 forces the CO2 off-gas within the snow chamber 11 to pass through the openings 16 in the mesh conduit 3 positioned along the surface of the mesh conduit 3, enter the inner passage 14 of the mesh conduit 3, and then exit through the opening 13 in the snow filler 4. It should be understood that other means of sealing can be implemented in accordance with the present invention. For example, referring to the filler system 400 of FIG. 4a, sealing can occur at a lower portion of the sleeve 402 extending along the outer surface of the conduit 403, thereby creating a seal between the sleeve 402 and the neck of the container 2.

[0042] Having described the structural components and assembly of the CO2 snow making kit 1, one aspect of the present invention relating to a method for filling and making CO2 snow blocks 10 within a transportable container 2 will now be discussed with reference to Figures 1a, 1b, 2, and 5. As shown in Figure 1a, the assembled CO2 snow making kit 1 is placed in a filling station 500 on a weigh scale 504, as shown in Figure 5. Although not shown, a programmer A programmable logic controller (PLC) is preferably integrated with the weigh scale 504 to control the amount of CO2 fluid introduced into the kit 1. A PLC display allows the user to monitor the filling process. The PLC display also preferably indicates when filling is complete.

[0043] Pressure regulating devices, differential pressure transmitters, control valves, and manual valves may be configured as part of the filling process for delivery of CO2 fluid to kit 1. It should be understood that the exact conduit and valve configuration is not drawn to scale and certain features have been intentionally omitted to better illustrate the filling process utilizing kit 1.

[0044] The CO2 snow making kit 1 has an outlet opening 13 (i.e., a vent opening) in the snow charger 4. The opening 13 can be connected to a suitable conduit to a ventilation system 501 that captures CO2 off-gas created during the generation of the in-situ CO2 snow blocks 10 in the snow chamber 11. The venting removes CO2 off-gas generated from the CO2 snow process, thereby providing a safe operating environment. Optionally, a pressure relief valve can be provided on or in close proximity to the sleeve 9. The inlet of the kit 1 is operably connected to a CO2 source 502 through a central opening 15 in the conduit flow network 8, which will generally store CO2 fluid at a pressure of 2 MPa to 6 MPa (300 to 900 psig). The CO2 source 502 may comprise any suitable container, as defined above, including, but not limited to, a cylinder, a dewar, a bottle, or a microbulk or bulk tank. The CO2 source 502 may be equipped with safety features, such as a relief valve and a burst disk. A conduit extends from the CO 2 source 502 to the central opening 15 of the conduit flow network 8 of the snow loader 4 .

[0045] When CO2 filling is ready to begin, the door 503 of the filling station 500 is closed. A safety interlock is provided in the filling station 500 so that the door 503 remains locked during CO2 filling. The vent system 501 is activated.

[0046] A button on the filling station 500 can be pressed to activate the filling process. Pressurized CO2 fluid is introduced from a CO2 source 502 into a conduit operatively connecting the source 502 to the container 2. Preferably, the CO2 fluid is CO2 liquid, and CO2 gas is added to the conduit to prevent the pressure of the liquid CO2 from dropping below a certain pressure (e.g., about 1.0 MPa (150 psig)) to ensure that the liquid CO2 does not prematurely undergo a phase change to a solid and gas within the conduit.

[0047] CO2 fluid is directed into the snow charger 4 at the central opening 15 of the conduit flow network 8, as indicated by the downward dotted arrow in FIG. 1a. The CO2 fluid is then uniformly distributed within the conduit flow network 8 toward each of the four nozzles 12, as indicated by the horizontal dotted lines within the snow charger 4 in FIG. 1a. The four nozzles 12 are angled to direct or inject the CO2 fluid into the snow chamber 11 and toward the vacuum insulated side wall 6 while substantially avoiding injection into the inner passage 14 of the mesh conduit 3. In a preferred embodiment, the snow chamber 11 represents an annular region between the mesh conduit 3 and the vacuum insulated side wall 6 of the container 2. Other designs are contemplated where the snow chamber 11 has a non-annular shape surrounding the mesh conduit 3. Liquid CO2 fluid passes through the nozzles 12. As liquid CO2 passes through nozzle 12 and enters snow chamber 11, a pressure and temperature drop occurs, producing solid particle CO2 snow blocks 10 and CO2 off-gas in snow chamber 11.

[0048] The openings 16 in the mesh conduit 3 are sized to allow the passage of CO2 off-gas but to substantially block the ingress of CO2 snow particles. The passage of the CO2 off-gas through the opening 13 of the snow filler 4 is then the only path for the CO2 off-gas to be removed from the container 2. As the CO2 off-gas flows through the mesh conduit 3, it has the desired effect of compressing the snow particles, forming and depositing snow blocks 10 within the snow chamber 11. As used herein with reference to the filling method of operating the CO2 snow making kit 1, the term "compressing" refers to compressing the snow particles into CO2 snow blocks 10. Compression in accordance with the principles of the present invention affects the amount of CO2 snow blocks 10 that can be generated in situ within the snow chamber 11 and loaded into the transportable container 2.

[0049] The present invention has the ability to utilize the formation of CO2 off-gas to compress snow block 10 before it exits container 2 through openings 13 on snow filler 4. CO2 off-gas flows upward within inner passage 14 of mesh conduit 3 (as indicated by the upward arrow in FIG. 1a) and emerges through openings 13 in snow filler 4. Openings 13 are more clearly shown in the top view of snow filler 4 in FIG. 1b. In this manner, inner passage 14 acts as an exhaust passage. CO2 off-gas can then be directed into a vent system 501 operably connected to container 2.

[0050] During the formation and deposition of the CO2 snow block 10, CO2 off-gas is produced within the snow chamber 11. The mesh conduit openings 16 are restricted in size, preventing the CO2 off-gas from freely flowing through the openings 16 into the inner passage 14. Thus, pressure is created within the snow chamber 11. The mesh conduit 3 provides resistance and has sufficient structural rigidity to resist substantial deformation due to the pressure within the snow chamber 11. In this manner, the compressed density of the CO2 snow block 10 can be increased within the annular region of the snow chamber 11. The resulting CO2 snow block 10 resembles a substantially ring-shaped block that tightly holds the snow particles. In one embodiment, the bulk density of the CO2 snow block 10 ranges from 881 to 1041 kilograms per cubic meter (55 to 65 pounds per cubic foot). The bulk density of the CO2 snow block 10 formed within the snow chamber 11 is at least partially related to the size of the mesh conduit openings 16. As the CO2 snow block 10 continues to form and compress within the snow chamber 11, the CO2 off-gas continues to pass with resistance (i.e., does not flow freely) from the snow chamber 11 through opening 16 in mesh conduit 3. The CO2 off-gas then flows through inner passage 14 and exits container 2 through opening 13 in snow filler 4. As can be seen, mesh conduit 3 (i) acts as a separating barrier for the CO2 snow particles and gas, (ii) provides resistance for compression of the CO2 snow block 10, (iii) creates an annular region within snow chamber 11 that holds and compresses the resulting CO2 snow block 10 in a substantially stationary position during the filling operation, and (iv) prevents the CO2 snow block 10 from collapsing within the inner passage.

[0051] CO2 snow particles continue to form in the snow chamber 11 in block form, and the scale 504 continues to monitor the weight of the CO2 snow block 10 as it continues to form in the snow chamber 11. When the target setpoint weight of the CO2 snow block 10 is produced, the PLC automatically relays a signal to the appropriate control valve to shut off the supply of liquid CO2 from the liquid CO2 source 502. Generally, the setpoint weight of the CO2 snow block 10 is defined as the weight of the CO2 snow block 10 needed to maintain a sample product holder space or mesh conduit 3 space below a critical threshold (i.e., predetermined) temperature for a certain number of days, thereby ensuring that the item being transported in the container 2 remains preserved and usable upon arrival at its final destination. As an example, when the item is a biological sample, the sample is usable for testing purposes upon arrival at its destination. Appropriate indications of completion of filling can be visually displayed at the filling station 500, and optional remote alerts and notifications to the user may be provided.

[0052] Upon completion of filling, the PLC releases the safety interlock so that the fill door 503 can be released by the user. In this manner, the in-situ automatic generation of CO2 snow blocks 10 by the snow making kit 1 avoids the need to handle dry ice pellets or blocks and the need to maintain an inventory of dry ice pellets or blocks on-site. It should be understood that the filling process can also be manually shut off when the set point weight of the CO2 snow blocks 10 is achieved.

[0053] In another embodiment, filling occurs until it is determined that the CO2 snow block 10 is filled to or approximately to the top of the container 2; a predetermined set point weight of the snow block 10 may optionally be used to determine when the filling process should stop, although such a predetermined set point weight is not necessarily required in this particular method for filling the snow block 10 into the container 2. Any detection means, some of which are described below, may be used to determine when the CO2 snow block 10 is filled to or approximately to the top of the container 2.

[0054] In an alternative mode of operation, the automatic or manual shutoff for the CO2 filling station 500 is based not on how much CO2 weight has been added to the container 2, but on the pressure created within the snow storage area. Detection of a certain head pressure level or pressure rise can be used to determine when to stop the supply from the liquid CO2 source. Other detection means for determining when filling is complete can also be provided. For example, but not limited to, filling can be manually or automatically shut off upon reaching a certain time, temperature, and / or volume level within the container 2. Thus, the present invention contemplates employing a pressure indicator, differential pressure, temperature sensor, timer, volume measurement, or any combination thereof. It should be understood that completion of the filling method described herein can mean when the snow block 10 is filled (i) to the top of the container 2, (ii) to approximately the top of the container 2 (e.g., 80% or more of the maximum pre-volume capacity of the snow chamber 11), or (iii) to some predetermined portion of the maximum volume of the snow chamber 11 of the container 2.

[0055] In a preferred embodiment, a single and full fill of CO2 snow blocks 10 into container 2 is performed based on filling to a predetermined weight of CO2 snow blocks 10 until it is determined that the CO2 snow blocks 10 substantially fill snow chamber 11. Alternatively, it should be understood that a single fill can be performed such that CO2 snow blocks 10 occupy only a portion of snow chamber 11. Additionally, it should be understood that any of the filling methods of the present invention can be based on any suitable detection means, including those described herein, and that filling can take one or more periods to create a single dry ice block 10 or multiple dry ice blocks 10 stacked together within container 2. Manual or automatic shutoff of filling is contemplated with either the filling method and detection means for determining when filling is complete.

[0056] In another aspect of the present invention, when filling is based on monitoring the weight of the dry ice blocks 10 until a set point or predetermined weight of dry ice blocks 10 is reached for a given insulated container 2 being used for filling, an initial estimate of the required weight of CO2 snow blocks 10 needed to be formed within the container 2 can be determined from Table 1 below, which is now described.

[0057] [Table 1]

[0058] First, the heat gain, Q, into the container, preferably container 2, is determined based on the formula shown in Table 1. R-value, as known in the art, is the overall insulating property of the container, A is the ambient temperature, T ext The entire surface of the insulated container 2 exposed to the ext is the environmental temperature that container 2 is expected to be exposed to on average during transport. Both A and R are known properties of container 2. This ΔT is the temperature difference between the environmental temperature (T ext ) and the temperature inside the container (T ins ) is an estimate calculated as the temperature difference between insis the temperature measured inside the container 2. Preferably, the thermocouple is ins 6. Position along or adjacent to the interior of the cover (e.g., the interior of the top cover 600 in FIG. 6) to measure T ext can be corrected or modified with an optional adjustment factor, α, that can account for seasonal average fluctuations between morning and afternoon temperatures. It should be understood that a more accurate estimate of ΔT may also be obtained using inside and / or outside temperature sensors, as will be explained below. With the determined ΔT and known values ​​A and R, Q is calculated. Q represents, on average, the desired rate of heat gain through the insulating walls and cover of a given container 2 used for filling and subsequent transportation of items stored inside the container. Next, with the determined Q, an estimated weight of dry ice needed for a given duration, t, during which an item in container 2 is expected to be transported inside the container can be determined. The estimated amount of dry ice block 10 is determined as (Q*t) / 572((Q*t) / 246), where 572(246) is the perceived sublimation energy required for CO2 snow to undergo direct phase transfer from solid to gas phase. This estimated weight of the dry ice snow block 10 can be input into the PLC as a set point weight to control when the completion of filling is achieved, or can be used manually as a set point weight during the process of filling the container 2. Upon detecting that the set point weight has been reached, the filling can be shut off either manually or automatically.

[0059] Selection of various operating variables can affect the filling operation and the manner in which CO2 snow blocks 10 are generated in situ within the transportable container 2. For example, the liquid CO2 supply pressure and the design of the snow charger 4 (e.g., the size, number, angle, location, and distribution of the nozzles 12) can affect the liquid CO2 flow rate, CO2 snow block 10 yield, and off-gas flow rate within the CO2 snow charger 4, as well as the distribution and compression of the snow blocks 10 within the snow chamber 11 and the time required to complete the filling operation. Furthermore, the ability of the mesh conduit 3 to act as a snow and off-gas barrier and provide sufficient resistance for compression of the snow blocks 10 can be governed, at least in part, by the size of the openings 16 in the mesh conduit 3 and the portion of the surface of the mesh conduit 3 that has the openings 16. Furthermore, the combination of a certain liquid CO2 supply pressure and snow charger 4 design can affect the ability of the charger 4 to continuously produce in situ snow blocks 10. Additionally, for a given application, there may be an optimum CO2 off-gas flow rate to suitably compress snow block 10 to a sufficient density. Such a suitable compression mechanism may operate with a range of liquid CO2 flow rates delivered through nozzle 12 of filler 4 and / or a range of CO2 off-gas flow rates exiting container 2.

[0060] The exact selection of operating variables may vary depending on several factors, including the shape of container 2 (e.g., cylindrical, polygonal, rectangular, or bottle-shaped), the vacuum insulation characteristics, or R-value, of container 2, durability characteristics, which are an indication of the duration or lifespan that a particular item within container 2 can be maintained at or below a certain temperature, the particular items being preserved during transport, and the amount of snow blocks 10 required to achieve preservation of a particular item for a certain number of days during transport to its final destination for handling, testing, and / or analysis by a user. Preferably, the operating variables are selected to achieve optimal filling and durability characteristics of container 2.

[0061] Once the filling operation of the CO2 snow blocks 10 into the container 2 is complete, the container 2 is disengaged from the CO2 source. The filler 4 and mesh conduit 3 are then removed from the container 2, thereby allowing a user to access the interior volume of the container 2. The vent system 501 may remain on while the filler 4 is removed to ensure all CO2 off-gas is directed into the vent system 501. Items to be transported within the container 2 are loaded into a product holder. The product holder is then inserted through the opening 7 of the container 2, occupying the same volume originally occupied by the mesh conduit 3. Alternatively, the product holder may be inserted into the container 2, and then the items may be loaded into the product holder. Alternatively, the mesh conduit 3 may remain permanently affixed to the interior of the container 2, and the product holder may be inserted into the mesh conduit 3. FIG. 6 shows one embodiment of a mesh conduit 3 within the container 2 along the bottom of the container 2. Other methods for attaching mesh conduit 3 within the bottom of container 2 or other areas within container 2 are contemplated by the present invention. By virtue of having mesh conduit 3 and product holder, transportable container 2 prevents CO2 snow or CO2 snow blocks from collapsing into the sample area, an advantage not offered by conventional dry ice shipping containers that do not utilize a product holder or mesh conduit 3.

[0062] Next, a top cover 600 with a mechanical seal (e.g., a cork-like structure as shown in FIG. 6 ) is inserted into the opening 7 of the vessel 2 to create containment of the product holder and items within the container during storage, preservation, and / or shipping of the samples contained therein. The top cover 600 with the mechanical seal houses zigzag channels or passageways through which CO2 off-gas can escape, thereby substantially reducing or eliminating CO2 gas pressure buildup that forms during storage, preservation, and / or shipping of the items within the container 2. The spacing of the passageways is preferably optimized to minimize heat gain within the container 2 from the atmosphere while allowing CO2 off-gas venting to minimize pressure buildup within the container 2. Other channel designs that vent excess CO2 pressure while minimizing heat gain within the container 2 are contemplated.

[0063] At this stage, the container 2 is configured for the storage, preservation, and transportation of items. As set forth above in accordance with the principles of the present invention, the durability or performance of the filled container 2 can be based on several factors, including, but not limited to, the amount of CO2 snow blocks 10 filled inside the container 2, the size of the container 2, including the size of the space occupied by the product holder, and the R-value or thermal insulation of the container 2. The durability of the container 2, as used above, can be characterized as the duration or lifespan that a particular item within the container 2 can be maintained at or below a certain temperature, such as, by way of example and not limitation, -60°C. The walls 6 of the container 2 are preferably vacuum insulated to provide sufficient thermal insulation. The level of vacuum insulation affects the R-value, such that larger vacuum insulated walls 6 result in a higher R-value of the container. In one embodiment, and in the examples herein below, As shown and described, tests conducted by the inventors in 2 hr C / kJ(18ft 2hr F / Btu). In other words, a container with a 5 kg (10 lbs) CO2 snow block made according to the present invention within the container at a vacuum of 1000 microns will maintain the sample or article within the container at temperatures of about -60°C or below for approximately 4 days. In another embodiment, the R-value of the container is about 7.9 m at a higher vacuum level of about 10 microns along the coated portion of the container 2. 2 hr C / kJ(180ft 2 hr F / Btu). In other words, a container with a 10 lbs. (5 kg.) CO2 snow block made according to the present invention within the container, with a 10 micron vacuum, will maintain a sample or item within the container at temperatures below about -60°C for approximately 37 days.

[0064] Other modifications of the present invention are contemplated. For example, it should be understood that the principles of the present invention as described herein are applicable to any type of container, including containers that are non-mailable or remain at a user's location, either permanently or temporarily, so that the container is employed solely for producing CO2 snow blocks therein. For example, a CO2 snow filler 4 with mesh conduits 3 can be utilized to generate in-situ CO2 snow within a standard shipping box, preferably in block form. In this regard, FIGS. 7a and 7b illustrate an alternative design of a CO2 snow filler system designed for generating in-situ CO2 snow within a standard shipping box. The CO2 snow filler system includes a snow filler and mesh conduits. As described above, the snow filler 4 is further defined by a conduit flow network that can vary in geometry and design to create a suitable CO2 fluid spray pattern and CO2 fluid flow distribution into the standard shipping box. The conduit flow network can have a plurality of elongated structures of a predetermined shape and pattern with nozzles embedded within the conduits.

[0065] Other variations to the CO2 snow impregnator are contemplated in addition to those shown in Figures 1b and 2. For example, Figures 4a and 4b show an upper portion of mesh conduit 3 located between end portions of sleeve 402 of impregnator 400. Conduit flow network 402 extends within sleeve 402.

[0066] Other types of designs for the filler, nozzle, and mesh conduit are also contemplated. For example, mesh conduits of different shapes other than cylindrical mesh conduits can be employed. In one embodiment, a tapered mesh conduit can be employed, with the upper portion having a larger diameter than the lower portion to facilitate insertion and removal of the mesh conduit from the interior of container 2. In another embodiment, the filler kit can be utilized where a cylindrical mesh conduit is attached to an inverted U-shaped flow network conduit, with the lower portion of the flow network connected to a reservoir portion having a triangular cross-section extending along the outer surface of the mesh conduit. The nozzle is positioned along the triangular portion and designed to spray downward into the chamber while substantially avoiding introduction into the mesh conduit. Other combinations of mesh conduit and CO2 snow filler designs are also contemplated. Furthermore, it should be understood that various other injection conduits or certain flow network conduits are contemplated by the present invention for carrying out the filling method of the present invention, other than the H-shaped conduit of Figure 3b and the cross-shaped conduits shown in Figures 1b and 4b. Still further, alternative structures may be employed to seal the snow filler to the container 2. For example, the sleeve of the snow filler may be flat at the top of the container 2 to mate and seal with a structural ring located inside the opening 7 of the container 2.

[0067] The product holder can be non-porous or porous. In a preferred embodiment, the product holder is non-porous, single-use, and capable of creating a sealed enclosure along the sides around the transported item. The product holder is structurally configured to isolate the transported item from the remainder of the interior space (i.e., snow chamber 11) within container 2. Many of the items shipped within container 2, including biological samples, can be kept in their own primary packaging, such as blood, which is typically contained in a sealed or capped glass vial or tube. In the unlikely event that a vial or tube bursts or breaks within container 2, the product holder is designed to contain the biological sample, thereby preventing contamination of the interior of container 2. In another embodiment, mesh conduit 3 is removably removed from snow filler 4 after completion of in situ CO2 snow block filling and formation and then remains within container 2 to act as a product holder. Alternatively, mesh conduit 3 can be permanently located within container 2 and act as a porous product holder.

[0068] Still further, the present invention contemplates an improved method for generating in situ CO2 blocks within a transportable container. One aspect of the present invention is illustrated in FIG. 10, which depicts a generalized schematic representation of a process 1000 that can enhance the packed density of the in situ CO2 blocks. It should be understood that certain details have been omitted from the process 1000 and that it may not be drawn to scale. For example, as shown in FIG. 10, the exact conduit and valve configuration is not drawn to scale, and certain features have been intentionally omitted, to better illustrate the filling operation. Generally, the process 1000 involves alternating the introduction of liquid CO2 with CO2 gas into the transportable container 1010 to improve the packed density of the CO2 in situ blocks 1099 formed within the transportable container 1010. Although not shown, the transportable container 1010 includes the features of the present invention described above, including a CO2 snow-making kit that includes a filler and mesh conduits. The transportable container 1010 is shown positioned within a filling station 1001. The container 1010 is introduced into the filling station 1001 by opening an access door 1053, which allows access to the filling station 1001. An access door sensor 1054 can be designed to detect whether the door 1053 is open or closed and prevent the introduction of CO2 fluid into the container 1010 when the door 1053 is open. The container 1010 is placed on a weigh scale 1055, and then the access door 1053 is closed.

[0069] An exhaust system is operably connected to the filling station 1001. The exhaust system is turned on to allow CO2 off-gas 1044 to vent through conduit 1050 into the exhaust system. Next, CO2 vapor valve 1094 is set to an open position (or confirmed to be in such an open position), and control valve 1100 is configured to an open position to allow CO2 gas to be drawn from CO2 source 1090 into gas conduit 1091. CO2 source 1090 contains CO2 gas in a headspace at source pressure. Pressure regulator 1080 ("PRV 1100") adjusts the pressure of the CO2 gas drawn from CO2 source 1090 to reduce the pressure from the source pressure to approximately 1.0 MPa (150 psig).

[0070] The gas conduit 1091 contains pressure transducers 1071 and 1070 and a pressure indicator 1078, each of which is disposed within the gas conduit 1091. The pressure transducer 1071 measures the pressure of the headspace within the CO2 source 1090, the pressure indicator 1078 measures the pressure of the CO2 gas stream after reduction to approximately 1.0 MPa (150 psig), and the pressure transducer 1070 measures the pressure of the CO2 stream entering the CO2 snow charger. As the CO2 gas flows through various portions of the gas conduit 1091, any residue and / or impurities are purged. The CO2 gas is directed into the container 1010, which does not contain any CO2 block 1099 at this point in the process 1000. The CO2 gas subsequently exits the transportable container 1010 through a vent in the CO2 charger, as described above. The purging process involving the CO2 gas can continue for any length of time. In one embodiment, the purge process may last approximately 30 seconds.

[0071] After approximately 30 seconds, with CO2 vapor valve 1094 remaining in the open position and control valve 1100 configured in the open position, liquid CO2 from CO2 source 1090 can be introduced through liquid conduit 1092 into container 1010, thereby initiating the generation of in-situ CO2 block 1099 according to the principles of the present invention, as described above. CO2 main liquid withdrawal valve 1093 is set to, or confirmed to be in, the open position, and CO2 liquid control valve 1200 is set to the open position. Because the supply pressure of the liquid CO2 stream flowing in conduit 1092 (e.g., approximately 2.4 MPa (350 psig)) is generally higher than the supply pressure of the CO2 gas stream flowing in gas conduit 1091 (e.g., approximately 1.0 MPa (150 psig)), CO2 gas remains in gas conduit 1091, stopping flow to container 1010 during the generation of CO2 block 1099 within container 1010. Check valve 1067 prevents CO2 liquid flow pressure from causing a backflow of CO2 gas in gas conduit 1091 back to the CO2 source 1090.

[0072] As the CO2 liquid enters the filler and then the container 1010, it undergoes a phase change, forming CO2 snow blocks 1099 within the container, and CO2 off-gas is generated and flows through the CO2 snow filler vent. CO2 off-gas 1044 enters the interior of the filling station 1001. An exhaust system pulls the CO2 off-gas 1044 through conduit 1050, thereby preventing a buildup of CO2 off-gas within the filling station 1001 and its surrounding environment. The flow of CO2 liquid continues for a period of time. In one embodiment, the liquid CO2 is allowed to enter the container 1010 for approximately 30 seconds, during which time the CO2 snow blocks 1099 are generated. After approximately 30 seconds, the CO2 liquid control valve 1200 is configured to a closed position. When the CO2 liquid control valve 1200 is closed, there is substantially no supply pressure for the liquid CO2 flow in the conduit 1092. As a result, the CO gas in gas conduit 1091 now has sufficient pressure (e.g., 1.0 MPa (150 psig)) to flow to the filler and then to container 1010, which is at atmospheric pressure. The CO gas flows into the snow chamber of container 1010. As the CO gas flows into the snow chamber of container 1010 and then into the mesh conduit, the snow block 1099 may become more compacted or compressed than would be achievable through CO off-gas generation alone in a continuous filling method. The CO gas then flows through the mesh conduit and through vent holes in the snow filler until it enters the interior of filling station 1001 as CO gas 1044. The CO gas is then vented through conduit 1050 and directed into the ventilation system.

[0073] By alternating CO2 gas purging and CO2 snow filling, the bulk density of the CO2 snow block 1099 can be higher than that formed in a continuous filling method. When the weigh scale 1055 reaches a predetermined weight, the liquid CO2 control valve 1200 changes to the closed position, followed by the CO2 gas control valve 1100. In this manner, the CO2 in-situ block 1099 can be formed on demand with improved compaction density, which translates to improved durability during transport of the container 1010.

[0074] During process 1000, PLC 1085 is in electrical communication with pressure transducers 1070 and 1071, control valves 1100 and 1200, meter 1055, access door sensor 1054, and the exhaust / vent system. These electrical connections allow for the transmission and communication of signals between PLC 1085 and such components, thereby ensuring regulation and control of process 1000.

[0075] Safety relief valves 1086 and 1087 (“SRV 1102 and SRV 1200”) are used to prevent the gas conduit 1000 from leaking when shutting down various system components of the process 1000. The control valves 1200 and 1092 are designed to relieve residual pressure that may build up in the CO2 gas 1091 and / or liquid conduits 1092, respectively. For example, when the system is shut down, the control valve 1200 is closed and the primary liquid withdrawal valve 1093 is also closed. Remaining liquid CO2 may accumulate along the portion of the liquid conduit 1092 that extends from the control valve 1200 to the primary liquid withdrawal valve 1093. When the accumulated liquid CO2 eventually sublimes into CO2 gas, the pressure buildup can be relieved by the safety relief valve 1087, which in one embodiment is set to operate at 3 MPa (400 psig). The safety relief valve 1086 also acts to relieve pressure if or when the pressure buildup in the CO2 gas 1091 conduit reaches 3 MPa (400 psig).

[0076] It should be understood that the various operating parameters presented herein are merely illustrative and can be modified as needed to suit the particular in situ CO2 block generation within the transportable container 1010. It is further understood that different steps can be employed to achieve the process 1000 with similar results, thereby resulting in the introduction of liquid CO2 alternating with CO2 gas into the transportable container 1010 to improve the compaction density of the resulting CO2 in situ block 1099 within the transportable container 1010.

[0077] Additionally, other modifications are contemplated by the present invention. For example, cleaning or disinfecting processes can be incorporated into the present invention. In this regard, the container 2 of FIGS. 1a and 6 may be configured to allow exposure of the interior of the container 2 to cleaning or disinfecting fluid. The mesh conduit 3 or product holder is removed during the cleaning or disinfecting process. In one embodiment, a closure known in the art can be installed within the container 2 with one or more conduits passing through the closure. Disinfectant or cleaning fluid can then flow into the closure, filling the container. The fluid is retained within the container for a target retention time. Alternatively, the closure may contain one or more additional conduits passing through the closure to allow flow of cleaning or disinfecting fluid into the container 2 and out of the container 2 for a target time. The container 2 may also be directly equipped with one or more ports for supplying and removing cleaning or disinfecting fluid. After cleaning / disinfecting is completed, the closure can be removed from the interior of the container 2.

[0078] Another embodiment of the present invention includes configuring each container 2 with a unique identifier that can be read electronically or physically to identify certain aspects of the container 2 used for the filling process and subsequent transport of the items stored in the container to their destination. By way of example, the unique identifier may be a barcode, a quick response (QR) code, or a near field communication (NFC) tag with embedded information unique to that particular container 2. Representative examples of embedded information in a barcode, QR code, or NFC tag or other unique identifier of a container 2 may include container identification information, such as, but not limited to, the container's tare weight, the initial and actual weight of the snow blocks 10 loaded into the container 2, durability characteristics, the type of container 2, the time the container 2 was filled, the date and time the container 2 was filled, the destination of the container 2, the type of item(s) being transported in the container 2, and other specific information about the items, including, by way of example, the warmest temperature the items may be exposed to in the container 2 and the duration at that temperature, and traceability of the location of the container 2. The container identification information embedded within this type of unique identifier can include the intended durability of the container 2 and provide a reference to the history of that particular container 2. The container identification information can be readable through a scanner, such as, by way of example, a QR scanner, a barcode scanner, or other means. In this manner, the container identification information that is read or scanned can be stored in the cloud. Alternatively, a database, such as a cloud database, can be employed to maintain all necessary container identification information.

[0079] If desired, the identity and traceability of the container 2, along with the fill information, can be maintained and verified by the user during transport to the destination. In one embodiment, when the unique identifier of the container 2 is scanned, the container identification information read from the unique identifier can be linked, matched, or cross-referenced to the samples or items loaded into the container 2 by the user.

[0080] In addition to container identification information, temperature data and other location and traceability information can also be measured and recorded during transport of the container 2 along with the items stored therein. For example, an interior temperature sensor may be positioned along or adjacent to the interior region of the container 2's cover (e.g., cover 600 in FIG. 6 ) to monitor the temperature within the container 2. Such an interior temperature sensor may also be a means for detecting when the container 2's cover is removed from the container 2. Alternatively, or in addition, an exterior temperature sensor may be positioned along the exterior of the container 2 to measure the environmental temperature surrounding the container 2 in certain cases. Such an exterior temperature sensor can detect when the container 2 is exposed to a higher-than-expected environmental temperature, thereby allowing the distribution route of the container 2 to be rerouted as necessary to avoid exposure to higher-than-intended environmental temperatures. Thus, the preservation capabilities of the items stored within the container 2 are enhanced. Furthermore, additional temperature sensors may be installed inside the container 2 to monitor the temperature of the space surrounding the items (i.e., the area of ​​the product holder or mesh conduit 3).

[0081] By using such temperature sensors, the temperature difference between the ambient temperature and the temperature inside the container 2 can be used to more accurately estimate the durability of a particular container 2. The temperature data can also be used to better simulate the intended durability characteristics of the container 2 at the facility where the filling occurred, and the snow block 10 consumption during transport of the container 2. In this manner, confidence in the intended performance of the container 2 can be increased before the container 2 is deployed to a user. Furthermore, the behavior history of the container 2 (e.g., snow block 10 consumption, average ambient temperature, average internal temperature of the container 2) can be utilized to set alerts for any abnormal behavior and / or shipping conditions of the container 2 detected during transport.

[0082] The measured temperature data can be stored on a data chip within the container 2, and the tracked temperature data as well as other data can be subsequently downloaded as needed when the container 2 arrives at its destination, thereby allowing a user to access and use the data in conjunction with the selection of the container 2 to potentially make specific decisions about the filling process and / or better map the delivery route of the container 2 from origin to destination.

[0083] Many means can be used to transfer data, including a Universal Serial Bus (USB) connection or other suitable transfer means. Additionally, a customized application for a smartphone can be deployed to synchronize temperature data and other information, such as customer identification information, through wireless connectivity, including, by way of example, Bluetooth® wireless connectivity. Furthermore, a wireless telemetry device can be installed on container 2, and once the gateway is operational, generated information, including container identification and measurement data, can be remotely transferred over a cellular network to the gateway and sensor cloud for use on websites and in specific applications. The present invention contemplates other suitable transfer means known in the art or that may be developed in the future for transferring information (i) generated from the container's unique identifier, (ii) measured, (iii) tracked, and / or (iv) stored during the filling and transportation of container 2.

[0084] It should be understood that other sensors can be incorporated into the container 2. For example, one or more sensors can be configured on the container 2 to enable location tracking of the container 2. The location tracking can be correlated to temperature data and tracking of specific activities, such as, by way of example, identifying which items are located within which container 2. In this manner, real-time information about the location of the container 2 and the health of the items within the container 2 is possible, allowing real-time corrective action to be taken to prevent damage to the items. Furthermore, the container identification information, in conjunction with other information recorded and tracked during filling and / or transportation, can be utilized to estimate the amount of snow blocks 10 consumed during transportation. In another embodiment, the tracking information and container identification information can also be used to allow a user to refill previously shipped containers that may or may not have contained snow blocks 10. This information can be used to determine how many additional snow blocks 10 are needed during the filling process to provide additional use or life to the container 2 for subsequent transportation of specific items to a specific destination.

[0085] Additionally, the present invention has application in a variety of applications, including, but not limited to, transport and storage of biological samples, personal items, poultry and dairy products.

[0086] The ability of the CO2 snow making kit of the present invention to charge CO2 in situ in a transportable container that exhibits sufficient temperature retention or durability and produce CO2 snow blocks is demonstrated by the following tests.

[0087] Comparative Example 1 (Standard Shipping Container) Commercially available CO2 dry ice pellets, 1 centimeter (0.5 inch) in diameter, were manually scooped and placed into the standard shipping box shown in Figure 9. The standard shipping box is commercially available from Sonoco Thermosafe and consists of three layers of insulation, including an outer cardboard box, an expanded polystyrene insulation layer, and vacuum insulation panels. A 1 cm (0.5 inch) dry ice pellet was placed inside the innermost box. A thermocouple was placed near the top of the shipping box.

[0088] Temperature measurements were taken for approximately 96 hours and the results are shown in Figure 8. The temperature within the standard shipping container gradually increased throughout the course of the test. [Example]

[0089] Example 1 (present invention) In accordance with the principles of the present invention, a prototype kit, as shown in FIG. 1a, was fabricated and assembled to produce a CO2 snow block. A cylindrical mesh tube was inserted and installed inside a generally cylindrical container. The container had an overall height (defined as the height from the bottom-most point of the container 2 to the top-most point of the container 2) of 49.3 centimeters (19.4 inches), a neck diameter of 9.09 centimeters (3.58 inches), and an overall diameter (defined as the widest point of the container 2 from sidewall to sidewall) of 23 centimeters (9.2 inches). The total internal storage volume was approximately 6 liters, with the top cover secured to the top of the container. The cylindrical mesh tube had a volume of approximately 1 liter.

[0090] A snow filler containing an annular flow conduit network was connected to the upper portion of the mesh conduit with multiple nozzles positioned along the periphery of the annular flow conduit network, the central opening of which was then connected to a CO2 pipe attached to a liquid CO2 source.

[0091] Liquid CO was introduced from a liquid CO gas source with CO gas to ensure that the pressure of the liquid CO did not drop below 1.0 MPa (150 psig), thereby avoiding premature formation of solid CO in the pipes and / or nozzles of the annular flow conduit network, which could potentially clog the piping and / or nozzles.

[0092] CO2 snow particles and CO2 off-gas were produced in the container. The CO2 off-gas passed through a mesh tube and then exited the container. A small amount of CO2 snow particles were observed to pass through and form within the inner passages of the mesh tube.

[0093] Filling continued until 4.76 kg (10.5 lbs.) of CO2 snow particles had accumulated in the container. The CO2 snow appeared to be annular in shape with an approximately block-shaped consistency of closely held particles. The CO2 snow blocks appeared visually to be much denser than the typical consistency of conventional fluffy CO2 snow particles produced when pressurized liquid CO2 fluid is introduced into an empty container at ambient temperature and pressure conditions.

[0094] The properties of the CO2 snow blocks were then determined and compared to those of commercially available 1 cm (0.5") diameter CO2 dry ice pellets. Bulk density was determined by calculating the ratio of the volume of the void space in the container filled with CO2 snow blocks or dry ice pellets to the weight of the CO2 snow blocks or dry ice pellets. In this manner, a bulk density of 961 g / L (60.0 lb / ft) was determined for the CO2 snow blocks produced by the filling method of the present invention. 3 ) was determined. Commercially available CO2 dry ice pellets, 1 cm (0.5") in diameter, were packed into the same volume as the container utilized to create the CO2 snow blocks. Generally, CO2 dry ice pellets, which represent the standard for obtaining acceptable dry ice density, were determined to be 948 g / L (59.2 lb / ft) when used in the prototype kit. 3These results demonstrate that the filling method of the present invention is capable of producing relatively high density CO2 snow blocks with bulk densities comparable to or higher than the bulk densities of the CO2 dry ice pellets filled in the prototype kits.

[0095] Example 2 (present invention) The temperature profile of a prototype of the present invention was evaluated with CO2 snow blocks produced within the prototype, as described in Example 1, and then compared to the temperature profile of CO2 dry ice pellets contained within a standard shipping container, as described in Comparative Example 1.

[0096] The mesh tube and snow packer were removed from the prototype kit container. A thermocouple was then placed slightly below the bottom of the container cover. The top cover was placed over the opening of the container.

[0097] Temperature measurements were taken for approximately 96 hours. Results showed that the prototype container with the CO2 snow block generated in situ within the container experienced temperatures below -60°C for 90 hours. The results are shown in Figure 8. The temperature at a given time represents the average of temperature measurements taken from different thermocouples located within the container. The temperature profile of the inventive prototype remained at a lower temperature for a longer period of time compared to that of the standard shipping box. Additionally, it was observed that the inventive prototype kit experienced less temperature change within its sample space than that of the standard shipping box.

[0098] Example 3 (present invention) The effect of different R-values ​​on the performance of the prototype kit of the present invention was evaluated. As known in the art, R-value is a measure of thermal resistance used to quantify durability and is an indicator of the duration an item can be maintained within a container at a temperature below a certain predetermined temperature. In the tests performed herein, the predetermined no-exceed temperature was -60°C. The same containers used in Examples 1 and 2 were used to perform the tests. The initially manufactured containers were vacuum-sealed to a level of 1000 microns. The containers included vacuum ports to allow access to the vacuum-insulated walls. A vacuum device was connected to the vacuum port as needed to achieve different vacuum levels to evaluate durability.

[0099] In the first test, the durability of a container with approximately 1000 microns of vacuum insulation coating was evaluated. CO2 snow blocks were manufactured according to the inventive filling method described in Example 1. A temperature profile of the container was then generated as described in Example 2. The temperatures were measured and the graphical results are labeled "Inventive Prototype" as shown in Figure 8. The data indicate that the sample space inside the container did not reach a temperature warmer than -60°C for nearly four days. Based on the temperature data, the R-value of the shipping container was calculated to be 0.79m 2 hr℃ / kJ(18ft 2 hr°F / Btu).

[0100] In a second test, a vacuum device was connected to the vacuum port to reduce the vacuum level within the coating from 1000 microns to approximately 10 microns. CO2 snow blocks were manufactured according to the inventive filling method described in Example 1. The temperature of the container was then generated as described in Example 2. The temperature was measured and a graphical result is labeled "Inventive Prototype," as shown in FIG. 11. The data indicate that the internal storage space of the container did not reach a temperature warmer than -60°C for nearly 37 days. Thus, these tests demonstrate that the durability of the container increased by more than 9 times when the vacuum level was increased by 100 times.

[0101] While we have shown and described what are considered to be particular embodiments of the present invention, it will of course be understood that various modifications and changes in form or detail can be readily made therein without departing from the spirit and scope of the invention. It is therefore intended that the present invention not be limited to the exact forms and details shown and described herein, nor be limited to anything less than the full scope of the invention disclosed herein and claimed below.

Claims

1. CO in the container ２ Filled on-site, CO ２ CO to create snow blocks ２ A snow making kit, the kit comprising: A container including an interior volume defined by an inner mesh conduit volume and a snow chamber, ２ a container configured to generate and store snow blocks within the snow chamber, the interior volume being further bounded by a plurality of container walls; the inner mesh conduit volume configured to receive a mesh conduit; Gas is passed through, but the CO ２ said mesh conduit having openings sufficiently porous to allow snow blocks to remain substantially within said snow chamber; CO ２ A snow filler, ２ The snow filler is CO ２ configured to selectively direct liquid into the snow chamber; ２ The snow charger further comprises one or more nozzles in fluid communication with the snow chamber. ２ Snow filler; Equipped with The snow chamber at least partially surrounds the mesh conduit, and the CO2 snow filler is connected to the mesh conduit such that a nozzle of the CO2 snow filler is directed toward the snow chamber.

2. CO in the container ２ 1. A method for filling snow blocks in place, said method comprising: CO ２ The liquid is transferred to a CO ２ feeding a snow filler, the mesh conduit being positioned within the interior of the container; The CO ２ Selectively directing a liquid into the snow chamber; In the snow chamber, ２ generating snow particles and gas in situ; passing the gas through the mesh conduit; Including, The method, wherein the snow chamber at least partially surrounds the mesh conduit, and further wherein the CO2 snow filler is connected to the mesh conduit, with a nozzle of the CO2 snow filler directed toward the snow chamber.

3. The method comprises: ２ Compressing the snow particles to essentially CO ２ The method of claim 2 further comprising forming a snow block.

4. The method includes: ２ without substantial movement or passage of snow particles. ２ The method of claim 2 further comprising depositing snow particles in-situ in the snow chamber.

5. CO in container ２ On-site CO generation for on-site snow block generation ２ 1. A method for assembling a snow filling system, the method comprising: CO ２ providing a source; providing a container, said container further comprising an interior product volume and a snow chamber; providing a mesh conduit; inserting the mesh conduit into the container; CO ２ providing a snow filler; The CO ２ connecting a snow filler to the mesh conduit; CO ２ The CO 2 is preferably disposed in a manner that directs liquid into the snow chamber but not into the inner product volume. ２ constructing a snow filler; The CO ２ The second end of the snow filler is connected to the CO ２ connecting to a source; Including, The method, wherein the snow chamber at least partially surrounds the mesh conduit, and further wherein the CO2 snow filler is connected to the mesh conduit, with a nozzle of the CO2 snow filler directed toward the snow chamber.

6. The method includes the step of: ２ The method of claim 5 further comprising connecting the first end of a snow filler to the mesh conduit.

7. CO in the snow room ２ CO adapted to produce snow blocks ２ 1. A snow filler system, comprising: a mesh conduit, the mesh conduit having porous openings, the porous openings being adapted to allow CO ２ The CO ２ a mesh conduit that substantially intercepts snow block particles; CO ２ A snow filler, ２ The snow filler is CO ２ configured to selectively direct liquid into the snow chamber. ２ Snow filler; Equipped with The snow chamber at least partially surrounds the mesh conduit, and the CO 2 snow charger is connected to the mesh conduit.

8. An inner mesh conduit volume defines an interior of a container and is configured to receive the mesh conduit, and the CO ２ The snow filler system of claim 7 , wherein a nozzle of the snow filler is oriented toward the inner mesh conduit volume.

9. An inner mesh conduit volume defines an interior of a container and is configured to receive the mesh conduit, and the CO ２ The snow filler system of claim 7 , wherein a nozzle of the snow filler is oriented away from the inner mesh conduit volume.

10. 1. An apparatus configured for storing, preserving, or transporting one or more items, said apparatus comprising:

1. A container characterized by an interior volume including a first region and a second region, said first region being an interior product storage volume and said second region being a snow chamber, wherein CO ２ a container in which snow is stored, the container further comprising a plurality of insulated container walls at least partially enclosing the first region and the second region; a mesh conduit or product holder positioned within the interior product storage volume; Equipped with The CO ２ Substantially all of the snow is adapted to occupy the snow chamber, thereby ２ Snow is confined within the snow chamber; the interior product storage volume is separate and distinct from the snow chamber, the interior product storage volume adapted to receive one or more items for storage, preservation, and / or transport; The snow chamber at least partially surrounds the mesh conduit, and a CO2 snow filler is connected to the mesh conduit, with a nozzle of the CO2 snow filler directed toward the snow chamber.

11. 11. The apparatus of claim 10, wherein the interior volume of the container consists essentially of a snow chamber and an interior product storage volume.

12. 11. The device of claim 10, wherein the snow chamber is externally positioned relative to the inner product storage volume, and the inner product storage volume is located within the mesh conduit or the product holder.

13. 11. The apparatus of claim 10, further comprising a unique identifier configured to embed container identification information therein, the container identification information being retrievable by reading the unique identifier.

14. The wall comprises a getter material positioned within the wall, the getter material maintaining a vacuum and insulation level, and the CO ２ 11. The device of claim 10, suitable for use with snow.

15. 11. The device of claim 10, wherein the snow chamber does not have a foam filler material or absorbent material.

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