MXPA99005497A - Storage container - Google Patents

Abstract

The invention relates to a thermally insulated container which retains the temperature of the objects stored in its interior cavity below 10 ° C, the container comprises an exterior insulating cover and a continuous or segmented cooling surface, whereby the surface of cooling causes 70-100% of encapsulation of the cavity interi

Description

STORAGE CONTAINER TECHNICAL FIELD OF THE INVENTION The invention relates to improved low temperature containers for maintaining the contents at temperatures below 10 ° C even though the ambient temperature is very high.

BACKGROUND OF THE INVENTION Many perishable food items are transported / stored / distributed to consumers at temperatures below the ambient, either to prevent their decomposition due to biological actions (such as milk / fish / meat, etc.), or to preserve its physical, olfactory and mouth-feel characteristics during consumption (non-alcoholic beverages, frozen desserts, ice cream, etc.). For this purpose, containers of different types and sizes are used. Technically they are insulated to reduce the heat load on stored items. In addition, various means are used to keep the contents of these containers cool by heat extraction, for example, sometimes dry ice is added to the container to carry out this effect. Alternatively, sealed bags / pads containing refrigerants can be used to function as "refrigerant batteries" for this purpose. Such cooling pads are precooled or pre-frozen at a sufficiently low temperature and packaged together with the perishable foods to keep them in the desired temperature range. The cooling pads can be filled loosely. Alternatively, they can be stacked along vertical walls using a retainer device to improve the accessibility of the stored food items. Sometimes, cooling solutions are provided in sleeves attached to the vertical walls of the insulated containers used to store these food items. The refrigerant can be permanently sealed inside fixed covers. In such cases, the refrigerant can be cooled in line, continuously or intermittently by operating small refrigeration units permanently attached to the containers. Optionally, if the containers with sleeves are movable, they can be brought periodically to a service station for cooling / freezing the cooling solution in the sleeves / pads prior to temporarily coupling them to a central cooling / cooling unit. The refrigerant is chosen so that such refrigeration cabinets are generally used in ice cream retail sales, and can be completely or partially frozen using the installed refrigeration unit and provide the necessary cooling effect for the contents. Even if temporary power interruptions occur, or if the cabinet disconnects from the power supply and is transported for distribution in a vehicle, the partially or completely frozen refrigerant continues to provide the cooling effect while energy is not available to the unit. However, the container designs described above have a drawback. The stored items can not be kept within the desired temperature range, for sufficiently long periods of time especially if the ambient temperatures are very high, unless the refrigerant / cooling surfaces are kept at a temperature well below the temperature desired maximum of the stored food items. This requires the use of an engineered refrigeration system and results in higher energy consumption. For example, in the case of ice cream, one would like to distribute the product near or below -18 ° C for better results. The typical initial temperature of the ice cream at the moment of loading inside the container is -20 ° C. It has been observed that under hot and aggressive environmental conditions such as those found in tropical countries, the temperature of the ice cream stored in the containers described above increases rapidly to a temperature higher than -18 ° C, despite the presence of cooling pads or covers. BR 9501576 discloses freezer cabinets designed to store frozen food products by providing a eutectic material inside the cabinets to maintain very low temperatures inside the covers or pads. The recommended cooling temperatures are -27 ° C and below for ice cream maintenance at or below -18 ° C for a reasonable period of time. In general, this is an impractical and expensive option in tropical countries where ambient temperatures are relatively high and even a small reduction in the temperature of the refrigerant establishes excessive demands on refrigeration systems, especially when the power source is erratic and expensive. The object of the present invention is to provide a suitable container that can maintain its contents at temperatures below 10 ° C under aggressive ennmental conditions for longer periods of time, without recourse to excessively low temperatures of the cooling surfaces. Another object of the present invention is to provide containers, particularly suitable for transport / storage / distribution of ice cream below and close to -18 ° C for extended periods of time under aggressive ennmental conditions, without resorting to excessively low surface temperatures. Cooling. Applicants have found that thermally insulated containers in which the temperature or content is maintained below a desired value for longer times can be provided without resorting to excessively low temperatures of cooling surfaces by providing a continuous or segmented envelope of Cooling surface with adequate coverage towards the contents of the container. Applicants have found that optimum results can be obtained by providing a cooling surface which encapsulates the interior storage space of the container by approximately 70-100%. Accordingly, the invention relates to a thermally insulated container for retaining the temperature of the objects stored in the interior cavity, below 10 ° C, comprising an external insulation cover and a continuous or segmented cooling surface provided between the external cover and the inner cavity which causes a greater or total encapsulation of the internal cavity. According to a preferred aspect, the invention relates to a thermally insulated container for maintaining the temperature of the objects stored in the interior cavity below 10 ° C, comprising an external insulation cover and a continuous or segmented cooling surface. provided between the outer shell and the inner cavity, which causes 70-100% encapsulation of the inner cavity. According to a more preferred aspect, the invention relates to a thermally insulated container for maintaining the temperature of the objects stored in the interior cavity, below 10 ° C, comprising an external insulation cover and a continuous cooling surface. or segmented provided between the outer shell and the inner cavity which causes 85-100% encapsulation of the inner cavity. According to a preferred aspect, the container is provided with an interior compartment that descends a space between the outer cover and the inner compartment. When the inner compartment is provided, the cooling surface is provided either in the space between the outer cover and the inner compartment or as an inner liner of the compartment. The temperature of the cooling surface is preferably in the range of 9 ° C to -45 ° C, and more particularly, from 9 ° C to -30 ° C. The cooling surface can be provided in various alternative forms such as thermally conductive (eg metallic) sheets attached to cooling coils or sealed liners / peelable pads filled with a cooling medium, etc.

In a preferred embodiment of the invention, the cooling medium can be any suitable composition insofar as the medium has a high heat absorption capacity of > 50 Joules / g near or below the temperature range at which the content should be stored. In a more preferred embodiment of the invention, the cooling medium has a heat absorption capacity of > 50 Joules / g in the temperature range of -18 and -30 ° C. In a further preferred embodiment of the invention, the cooling medium has a heat absorption capacity of > 120 Joules / g between -18 and -30 ° C. In addition it is preferable to have a refrigerant composition which is compatible with food and with very little corrosion cavity towards the low cost materials commonly used in the construction of containers. The refrigerant can be selected from refrigerant gases such as R-12, CARE 30, aqueous solutions with freezing point depressants or cryogenic mixtures or eutectic mixtures of salts and water. It is preferred that the cooling liner completely encapsulates the object to be protected from heat exchange with the exterior. The shape of the container can be of a parallelepiped, cubic, cylindrical shape or any other suitable design. It is preferred that all the walls of the freezing cabinet are coated with the cooling liner so as to act as a thermal barrier between the stored objects and the outside atmosphere.

The coolant linings and pads can be made of suitable material capable of withstanding low temperatures. Examples of suitable material are low carbon steel, stainless steel, galvanized iron, plastic, polymeric material or other materials such as high density, medium or low density polyethylene, linear low density polyethylene, polyvinyl chloride, polycarbonate, polyester, sheets metallic, etc. It can be packaged in removable / removable units of varying constitution, shape and size. The principal objective and other objects of this invention and their advantages will be described below in greater detail, with reference to the non-limiting exemplary embodiments of the invention described in the following.

Examples: Demonstration under sale conditions Six sets of test data were generated for recipients of different designs used for the sale of ice cream. The container is of a nominal capacity of 150 liters, of 0.457 m in height, 0.508 m in width and 0.660 m in length. The lid has dimensions of 0.3 m x 0.5 m. The vessel is insulated with a PUF insulation of -75 mm (k ~ 25 mW / mK). In all tests, the ambient temperature was 40 ° C. The relative humidity of the ambient air is 80%. Ice cream was charged at -20 ° C. The lid of the container was opened for 90 seconds every 10 minutes and the temperatures of the ice cream cones (Cornetto) in the container were noted, during a period of 12 hours. The other parameters specific to each test are provided in the following.

Example 1 This is a container of conventional design with a cooling liner on the four vertical walls that surrounds -62% of the interior storage cavity, and contains an aqueous solution of sodium acetate with sodium benzoate that constitutes the main additive as the medium of cooling. The cooling surface is maintained at -20 ° C during the test.

Example 2 This is a container of conventional design with a cooling jacket of four vertical walls that wrap -62% of the interior storage cavity, and that contains an aqueous solution of sodium acetate with sodium benzoate that constitutes the main additive as the medium of cooling. The cooling surface area is increased by 50%, by filling additional refrigerant pads in the storage cavity of the container together with the ice cream. Through the test, the coolant surfaces of the sheath and the additional pads were maintained at -20 ° C. 3 This is a container of conventional design with a cooling jacket of four vertical walls that wraps -62% of the interior storage cavity, and that contains an aqueous solution of sodium acetate with sodium benzoate that constitutes the main additive as the medium of cooling. The coolant surface area is increased by 100% by filling additional coolant pads in the storage cavity of the container together with the ice cream. Through the test, the coolant surfaces of the sheath and the additional pads were maintained at -20 ° C.

Example 4 This was a container of conventional design with cooling covers on the four vertical walls that wrap -62% of the interior storage cavity. The covers contain eutectic saline solution as the cooling medium. The cooling surface is maintained at -30 ° C during the test.

Example 5 This was a container of conventional design with cooling covers on the four vertical walls that wrap -62% of the interior storage cavity. The liners contain eutectic aqueous saline solution as the cooling medium. The cooling surface is maintained at -35 ° C during the test.

Example 6 This was a modified design vessel with coolant covers on all the walls of the cabinet and it wrapped -93% of the interior storage cavity containing an aqueous solution of sodium acetate with sodium benzoate as the main additive as the medium Cooling. Coolant surfaces are maintained at -20 ° C during the test.

Table 1 Examples 1 to 6 show that the improved design vessel with cooling sleeves that are maintained at -20 ° C but that completely or nearly completely envelops the contents of the container provides better results to keep the temperature of the ice cream below -18. ° C in a 12-hour sales cycle. By increasing the surface area of the coolant by up to 100% in a conventionally designed container by having additional loose filled cooling pads not only does it increase the weight of the refrigerant, it is also not able to maintain the temperature of the ice cream below -18 ° C. in a 12-hour sales cycle. The choice of a cooling jacket that is maintained at -35 ° C is not practical and would not be economical because the energy requirement to obtain such lower and lower temperatures is significantly higher.

Demonstration under sealed conditions: Six sets of test data were generated for recipients of different designs used to store an ice cream under sealing conditions. In the following examples 7 to 12, the lid of the containers is kept closed during the test period and is not subjected to opening and closing. The container is of a nominal capacity of 150 liters, 0.457 ml in height, 0.508 m in width and 0.660 m in length. The layer has a dimension of 0.3 m x 0.5 m. The vessel is isolated with a cooling of -75 mm PUF (k - 25 mW / mK). In all tests, the ambient temperature was 40 ° C. The relative humidity of the ambient air was 80%. Ice cream is charged at -20 ° C. The other specific parameters for each test are as indicated in the following.

Example 7: This is a conventionally designed container with coolant covers on the four vertical walls that wrap -62% of the interior storage cavity. The sleeves contain an aqueous saline solution as the cooling medium. The cooling surface is maintained at -26 ° C during the test. The temperatures of the ice cream cones (Cornetto) in the container are recorded for a period of 12 hours.

Example 8: This is a conventionally designed container with cooling sleeves on the four vertical walls that wrap -62% of the interior storage cavity. The sleeves contain an aqueous saline solution as the cooling medium. The cooling surface is maintained at -27 ° C during the test. The temperatures of the ice cream cones (Cornetto) in the container are recorded for a period of 12 hours.

Example 9: This is a conventionally designed container with cooling sleeves on the four vertical walls that wrap -62% of the interior storage cavity. The sleeves contain an aqueous saline solution as the cooling medium. The cooling surface is maintained at -36 ° C during the test. The temperatures of the ice cream cones (Cornetto) in the container are noted for a period of 50 days.

Example 10: This is a conventionally designed container with cooling sleeves on the four vertical walls that wrap -62% of the interior storage cavity. The sleeves contain an aqueous saline solution as the cooling medium. The cooling surface is maintained at -37 ° C during the test. The temperatures of the ice cream cones (Cornetto) in the container are noted for a period of 50 days.

Example 11. This container is of modified design with cooling shells on a sheath of 93% of the interior storage cavity. The sleeves contain an aqueous solution of sodium acetate and sodium benzoate as the cooling medium. The cooling surface is maintained at -20 ° C during the test. The temperatures of the ice cream cones (Cornetto) were noted in the container during a period of 50 days.

Example 12. This was a container of modified design with cooling covers on, and which wrapped 100% of the interior storage cavity. The sleeves contain an aqueous solution of sodium acetate and sodium benzoate as the cooling medium. The cooling surface is maintained at -20 ° C during the test. The temperatures of the ice cream cones (Cornetto) were noted in the container during a period of 50 days.

Table II Examples 7 and 8 require a cooling surface temperature of -27 ° C in a conventionally designed container with 62% coverage of storage capacity, to keep the sides at a temperature below -18 ° C for a period of time. 12-hour period even if the lid remains closed for a period of 12 hours. Similarly, examples 9 and 10 show that the cooling surface temperature of 37 ° C or lower is necessary in a conventionally designed container with 62% coverage of the storage cavity, to keep the ice cream below -18 ° C for a period of 50 days if the lid remains closed during the 50 day period. On the other hand, examples 11 and 12 show that in a modified design container 93% to 100% encapsulation of the storage cavity is provided by the cooling surface, it is capable of retaining the ice cream of a temperature lower than -18. ° C for a period of 50 days if the lid is kept closed for the period of 50 days even if the cooling surface is maintained at -20 ° C which is well above the cooling surface temperatures required in examples 7 to 10. This improvement in ice cream retention in the region of the desired temperature of -18 ° C, even if the cooling surface is maintained at a relatively high temperature of -20 ° C by ensuring that the cooling surfaces provide a wrap 70 to 100% around the storage cavity for an ice cream is remarkable and unexpected.

Claims (6)

1. A thermally insulated container for retaining the temperature of the objects stored in the interior cavity below 10 ° C, the container is characterized in that it comprises an outer insulation cover and a segmented continuous cooling surface, whereby the cooling surface causes 70-100% encapsulation of the interior cavity.

2. The container according to claim 1, characterized in that the cooling surface causes 85-100% encapsulation.

3. The container according to claim 1 or 2, characterized in that the temperature of the cooling surface is from 9 to -30 ° C, and more preferably from -10 to -30 ° C.

4. The container according to claims 1 to 3, characterized in that the cooling surface is formed of detachable cooling pads filled with a cooling medium.

5. The container according to claims 1 to 3, characterized in that the cooling surface is formed of conductive sheets thermally bonded to the coolant cooling part.

6. The container according to claims 1 to 5, characterized in that the container is free of electricity supply or other power connection.