ITMI991322A1 - THERMAL INSULATED STORAGE CONTAINER - Google Patents

Description

DESCRIPTION

The invention relates to improved low temperature containers for maintaining the contents at temperatures below 10 ° C, even when the ambient temperature is very high.

Many perishable food products are transported / stored / distributed to consumers at temperatures below ambient temperatures, either to prevent their deterioration due to biological actions (for example as in the case of milk / fish / meat, etc.) or to preserve their physical, olfactory and sensation in the mouth during the consumption (soft drinks, frozen desserts, ice creams, etc.). For this purpose, containers of different types and sizes are used. They are thermally insulated to reduce the thermal load on the Preserved items. In addition, various means are employed to keep the contents of these containers cold by heat extraction. For example, sometimes dry ice is added to the container to cause this effect. Alternatively, sealed bags / pillows can be used. containing refrigerants to serve as "refrigerant batteries" for this purpose chilled or pre-frozen to a sufficiently low temperature and packaged with perishable food products to keep them in a desired temperature range. Refrigerant containers can be inserted loose or randomly. Alternatively, they can be stacked along vertical walls using a retention device to improve accessibility to stored or stored food items. Sometimes, refrigerant solutions are provided in liners attached to the vertical walls of the insulated containers used to store such food products. The coolant can be permanently sealed inside the fixed liners. In this case, the refrigerant can be cooled in line, continuously or intermittently, by operating small refrigeration units permanently fixed to the containers. Optionally, if the jacketed containers are mobile, they can be periodically taken to a service station for pre-cooling / freezing the refrigerant solution in the jackets / containers by temporarily coupling them to a central cooling / refrigeration unit.

The refrigerant is chosen in such cabinet freezers used in general in ice cream retailing, so that it can be frozen completely or partially using the installed refrigeration unit and provides the necessary cooling effect for the contents. Even if there are temporary power outages or if the refrigerated cabinet is disconnected from the power supply and brought to the vehicle for distribution, the partially or fully frozen refrigerant continues to provide cooling effect while the power supply is not available. to the unit.

However, the container models described above have a drawback. Stored items cannot be kept in the desired temperature range for sufficiently long periods of time, particularly if ambient temperatures are extremely high, unless the coolant / cooling surfaces are obtained at temperatures well below the desired maximum temperature of the items. preserved food items. This requires the use of a highly complex refrigeration system and results in higher energy consumption. For example, in the case of ice cream, you may want to distribute the product near or below -18 “C, for the best results. The typical initial temperature of ice cream at the time of loading into the container is -20 ° C. It is observed that in aggressive hot environment conditions such as those encountered in tropical countries, the temperature of the ice cream stored in the containers described above rapidly increases to over -18 ° C, despite the presence of cooling containers or jackets. -BR 9501576 discloses freezing cabinets (or freezers) designed for the storage of frozen food products by providing a eutectic material within the cabinets to maintain extremely low temperatures in the shirts or containers. Recommended coolant temperatures are -27 ° C and below to keep the ice cream at or below -18 ° C for a reasonable amount of time. In general, this is an impractical or expensive option in tropical countries where ambient temperatures are relatively high and even a small reduction in refrigerant temperature places undue demands on the refrigeration system, particularly when the electrical power source is erratic and expensive.

The object of the present invention is to provide a suitable container which can maintain its contents at temperatures below 10 ° C under aggressive environmental conditions for longer periods of time without resorting to disordered low temperatures of the cooling surfaces.

Another object of the present invention is to provide containers in particular suitable for the transport / storage / distribution of ice creams at temperatures below or close to -18 ° C over extended periods of time in aggressive environmental conditions, without resorting to the disordered low temperatures of the cooling surfaces.

Applicants have found that heat-insulated containers can be provided which the temperature of the contents is kept below a desired value for longer periods, without resorting to excessively low temperatures of the cooling surfaces by providing a continuous or segmented envelope of cooling surfaces. with adequate coverage to the contents of the container. Applicants have found that optimal results can be obtained by providing a cooling surface which encapsulates the internal storage space of the container by approximately 70-100%.

Consequently, the invention relates to a heat-insulated container for keeping the temperature of the objects stored in its internal cavity below 10 ° C, comprising an outer insulation shell and a continuous or segmented cooling surface, provided between the outer shell and the internal cavity causing a greater or total encapsulation of the internal cavity.

In accordance with a preferred aspect, the invention relates to a heat-insulated container for keeping the temperature of the objects stored in the internal cavity below 10 ° C, comprising an external insulation shell and a continuous or segmented cooling surface provided between the shell. external and internal cavity causing 70-100% encapsulation of the internal cavity.

In accordance with a more preferred aspect, the invention relates to a thermally insulated container for keeping the temperature of the objects stored in the internal cavity below 10 ° C, comprising an outer insulation shell and a continuous or segmented cooling surface provided between the outer shell and inner cavity causing 85-100% encapsulation of the inner cavity.

In accordance with a preferred aspect, the container is provided with an internal compartment which defines a space between the outer shell and the internal compartment. When the inner compartment is provided, the cooling surface is provided either in said space between the outer shell and the inner compartment or as an inner lining of the parcel.

The temperature of the cooling surface is preferably in the range between 9 ° C and -45 ° C and more particularly between 9 "C and -30" C The cooling surface can be provided in various alternative forms, such as for example heat conducting foils (e.g. metal) attached to refrigerant coils or sealed jackets / pads or detachable containers filled with a refrigerant medium, etc.

In a preferred embodiment of the invention, the cooling medium can be of any suitable composition such that the medium has a high heat absorption capacity of> 50 Joules / gram at or below the temperature range. where the content is to be stored. In a more preferred embodiment of the invention, the cooling medium has a heat absorption capacity of> 50 Joules / gram in the temperature range of -18 to -30 ° C. In yet another preferred embodiment of the invention, the cooling medium has a heat absorption capacity of> 120 Joules / gram in the temperature range of -18 to -30 ° C. It is also preferable to have a refrigerant composition which is compatible with food products and which has extremely low corrosivity towards the low cost materials commonly used used for the construction of the containers. The refrigerant can be selected from refrigerant gases such as R-12, CARE 30, aqueous solutions of freezing point lowering agents or cryogenic mixtures or eutectic mixtures of salts and water.

It is preferred that the cooling jacket completely encapsulates the objects to be designed by the heat exchange with the outside. The shape of the container can be parallelepiped, cube, cylinder or any other suitable model. It is preferred that all the walls of the freezing cabinet be lined with the refrigerant jacket in such a way that it acts as a heat barrier between the stored objects and the external atmosphere.

Coolant liners and pads can be made from suitable material that can withstand low temperatures. Examples of suitable material are low carbon steel, stainless steel, galvanized iron, plastic, polymeric or other materials such as high, medium or low density polyethylene, linear low density polyethylene, polyvinyl chloride, polycarbonate, polyester, foil metal -. lica, eco. It can be packaged in removable / detachable units of various shapes, sizes and shapes.

The main and other objects of the present invention and its advantages will now be described in greater detail with reference to the non-limiting exemplary embodiments of the invention described below.

Examples:

Demonstration in terms of sale;

Six test datasets were generated for different model containers used for ice cream sales. The container had a nominal capacity of 150 liters, a height of 0.457 m, a width of 0.508 m and a length of 0.660 m. The lid had dimensions of 0.3m X 0.5m.

The container was insulated with -75 mm PUF insulation (k - 25 mW / m K). In all tests, the ambient temperature was 40 ° C. The relative humidity of the ambient air was 80%. The ice cream was loaded 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 for a period of 12 hours. The other specific parameters for each test are provided below.

Example 1 "

Conventional model container with refrigerant jacket on four vertical walls that envelop - 62% of the internal storage cavity and containing, as cooling medium, an aqueous solution of sodium acetate with sodium benzoate as main additive. The cooling surface was kept at -20 ° C throughout the test. Example 2:

Conventional model container with refrigerant jacket on four vertical walls that envelop - 62% of the internal storage cavity and containing, as cooling medium, an aqueous solution of sodium acetate with sodium benzoate as main additive. The cooling surface was increased by 50% by inserting additional cooling pads or pillows into the storage cavity of the container along with the ice cream. Throughout the test, the cooling surfaces of the jacket and further pads were kept at -20 ° C.

Example 3:

Conventional model container with refrigerant jacket on four vertical walls that envelop - 62% of the internal storage cavity and containing, as cooling medium, an aqueous solution of sodium acetate with sodium benzoate as main additive. The cooling surface was increased by 100% by inserting additional pads or cooler containers into the storage cavity of the container along with the ice cream. Throughout the test, the cooling surfaces of the jacket and further pads were kept at -20 ° C.

Example 4:

Conventional model container with refrigerant jackets on four vertical walls that envelop - 62% of the internal storage cavity. The shirts contained, as a cooling medium, an aqueous solution of eutectic salt. The cooling surface was kept at -30 ° C throughout the test.

Example 5:

Conventional model containers with refrigerant jackets on four vertical walls that envelop - 62% of the internal storage cavity. The shirts contained, as a cooling medium, an aqueous solution of eutectic salt. The cooling surface was kept at -35 ° C throughout the test.

Example 6:

Modified model container with refrigerant jackets on all cabinet walls and enveloping - 93% of the internal storage cavity contained, as the cooling medium, an aqueous solution of sodium acetate with sodium benzoate as the main additive. The cooling surfaces were kept at -20 ° C throughout the test.

Table 1

Examples 1 to 6 reveal that improved model containers with refrigerant jackets kept at -20 ° but which completely or almost completely envelop the contents of the container give the best results in keeping the ice cream temperature below -18 ° C in a 12-hour sales cycle. Increasing the cooling area by 100% in a conventional model container by adding additional randomly inserted coolant pads may not only increase the weight of the coolant but also not be able to keep the ice cream temperature below. -18 ° C in a 12 hour sales cycle. Choosing a cooling jacket maintained at -35 ° C is not practical and would not be economical as the power requirement to obtain ever lower temperatures is significantly greater.

Demonstration in sealed conditions>

Six sets of test data were generated for different model containers used for storing ice cream under sealed conditions. In the following Examples 7 to 12, the container lid was kept closed during the test period and was not opened and closed. The container had a nominal capacity of 150 liters, a height of 0.457 m, a width of 0.508 m and a length of 0.660 m. The lid had dimensions of 0.3 ra X 0.5 m. The container was insulated with insulation - 75 mm PUF {k - 25 raW / m K). In all tests, the ambient temperature was 40 ° C. The relative humidity of the ambient air was 80%. The ice cream was loaded at -20 ° C. The other specific parameters for each test are provided below.

Example 7:

Conventional model container with cooling jackets on the four vertical walls that envelop - 62% of the internal storage cavity. The shirts contained, as a cooling medium, an aqueous solution of salt. The cooling surface was kept at -26 ° C throughout the test. The temperatures of the ice cream cones (Cornetto) in the container were noted over a 12 hour period.

Example 8:

Conventional model container with cooling jackets on the four vertical walls that envelop - 62% of the internal storage cavity. The shirts contained, as a cooling medium, an aqueous solution of salt. The cooling surface was kept at -27 ° C throughout the test. The temperatures of the ice cream cones (Cornetto) in the container were noted over a period of 12 hours.

Example 9i

Conventional model container with cooling jackets on the four vertical walls that envelop - 62% of the internal storage cavity. The shirts contained, as a cooling medium, an aqueous solution of salt. The cooling surface was kept at -36 ° C throughout the test. The temperatures of the ice cream cones (Cornetto) in the container were noted for a period of 50 days.

Example 10:

Conventional model container with cooling jackets on the four vertical walls that envelop - 62% of the internal storage cavity. The shirts contained, as a cooling medium, an aqueous solution of salt. The cooling surface was kept at -37 ° C throughout the test. The temperatures of the ice cream cones (Cornetto) in the container were noted for a period of 50 days.

Example 11

Modified model container with cooling jackets which envelop 93% of the internal storage cavity. The shirts contained, as a cooling medium, an aqueous solution of sodium acetate and sodium benzoate. The cooling surface was kept at -20 ° C throughout the test. The temperatures of the ice cream cones (Cornetto) in the container were noted for a period of 50 days.

Example 12:

Modified model container with cooling jackets that envelop 100% of the internal storage cavity. The shirts contained, as a cooling medium, an aqueous solution of sodium acetate and sodium benzoate. The cooling surface was kept at -20 ° C throughout the test. The temperatures of the ice cream cones (Cornetto) in the container were noted for a period of 50 days.

Table IX

Examples 7 and 8 show that a cooling surface temperature of -27 ° C or less is required in a conventional model container with 62% coverage of the storage cavity to keep ice creams below -18 ° C. for a 12-hour period even if the lid is kept closed throughout the 12-hour period.

Similarly, Examples 9 and 10 show that a cooling surface temperature of -37 ° C or less is required in a conventional model container with 62% coverage of the storage cavity to keep the ice creams at a temperature below -18. “C for a period of 50 days if the lid is kept closed for the entire period of 50 days.

On the other hand, Examples 11 and 12 show that in a modified model container it provides 93% -100% of the storage cavity encapsulation by the cooling surface, is able to keep the ice creams below -18 ° C for a period of 50 days if the lid is kept closed for the entire period of 50 days even if the cooling surface is kept at -20 ° C which is much higher than the temperatures of the cooling surfaces required in Examples 7 to 10.

This improvement in ice cream storage in the desired temperature region of -18 ° C even though the cooling surface is maintained at a relatively high temperature of -20 ° C ensuring that the cooling surfaces provide a 70-100% wrap around the surface. storage cavity for ice cream is remarkable is unexpected.

Claims (6)

CLAIMS 1. Earth-free container for keeping the temperature of the objects stored in the internal cavity below 10 ° C, said container comprising an external insulation shell and a continuous or segmented cooling surface, whereby the cooling surface causes an encapsulation of the 70-100% of the internal cavity. Container according to claim 1, wherein the cooling surface causes 85-100% encapsulation. Container according to claim 1 or 2, wherein the temperature of the cooling surface is between 9 and -30 ° C, more preferably between -10 and -30 ° C. Container according to claims 1-3, wherein the cooling surface is formed by removable cooling pads filled with cooling medium. 5. Container according to claims 1-3, wherein the cooling surface is formed by thermally conductive foils fixed to cooling coils. 6. Container according to claims 1-5, said container being devoid of electric power supply or other connection to electric power supplies.