RU2804552C1 - Inorganic composition for use in flameless food heaters - Google Patents

Abstract

FIELD: chemical heat sources.

SUBSTANCE: inorganic composition for use in flameless food heaters includes sodium chloride, copper chloride, aluminium, and water in the following ratio of components, wt.%: sodium chloride – 7.0–15.4; copper chloride – 8.9–18.9; aluminium – 2.8–6.0; water – 59.8–81.0.

EFFECT: ensuring stable heating of food products through the use of accessible components that do not require long-term and complex technical training and increased duration of the heating effect of the heating element.

1 cl, 1 tbl, 9 ex

Description

The invention relates to the field of chemical heat sources and can be used in autonomous heating devices for flameless heating of food (FLH) or personal devices (warmers).

A flameless food heater (FHF) is a portable compact device for heating finished products (canned food, rations).

A known composition for exothermic redox reactions between metals, metal oxides, activated carbon, graphite, inorganic salt and water. A feature of this invention is a fuel element made in the form of a three-layer flexible container containing a composition based on metals from the group of iron, magnesium, aluminum and zinc. As a second component, it additionally contains a metal oxide of variable valency from the group of manganese, lead and nickel. The container has an internal hydrophobic fabric shell, an intermediate airtight polymer shell and an outer shell made of decorative fabric. Inside the container there is an easily destructible partition (RU 2019160, IPC A61F 7/00, IPC C09K 5/00, pub. 09.15.1994).

However, the disadvantages of the known composition include uneven heat release, intense only in the initial stage of redox processes, the impossibility of mixing components before the start of the reaction, as well as the complex design of devices for individual use.

An exothermic composition for a flameless food heater based on magnesium alloy powder with a metal catalyst and a mixture reaction rate regulator is known. A feature of this invention is the use of iron and/or silicon as a metal catalyst, as a magnesium alloy powder with a metal catalyst with sizes of 200 - 500 microns, and as a reaction rate regulator, a mixture of magnesium alloy powder with a metal catalyst with particle sizes of 501 - 800 microns . Upon contact with an aqueous electrolyte solution, oxidation of the magnesium alloy powder occurs, releasing heat. In the presence of an electrolyte, the surface of the magnesium alloy is cleaned of the formed oxide film, which ensures its further oxidation, while the electrolyte also eliminates possible sticking of solution particles. (RU 2330868, IPC C09K 5/16, pub. 08/10/2008).

The disadvantages of this invention include the difficulty of obtaining components with given technical and mass characteristics and the high cost of using the proposed solutions.

An exothermic composition for food heaters is known which contains magnesium iron alloy powders, salt, surfactant and food grade acid anhydride or free acid. An anhydride or acid is used as a pH regulator, ranging from 4 to 7. The porous outer packaging can also be impregnated with acid. Staying within the specified pH values is necessary for the optimal reaction of magnesium with water. At lower pH values, the reaction begins to proceed at high speed, which is not desirable for the composition. At higher pH values, the opposite situation is observed; the reaction rate slows down greatly, which also affects the exothermic process of heating food (US 5117809, IPC A47J36/28, publ. 06/02/1992).

The disadvantages of the known invention include the presence in the composition of the required quantities of surfactants (surfactants), acid anhydrides or free acids, which reduces the content of the main component of the magnesium alloy, which has a detrimental effect on the main heat generation process.

Another well-known composition is a powder mixture, which, when interacting with water, enters into an exothermic reaction. The composition is placed in a structure consisting of two non-woven polyester sheets having many pockets into which a mixture consisting of masses is placed. %: magnesium and iron alloy (5% wt.) 80-85%; sodium chloride 5-7%; chemical defoamer 3-4%; inert filler 7-9% (US 5611329, IPC A47J36/28, publ. 03/18/1997).

The disadvantages of the existing invention is the presence of 15-20% additional components, which reduces the mass contribution of the main component - a mixture of magnesium and iron powder, which reduces the total amount of heat generated.

The technical result consists in the development of an inorganic composition for effective heat release, ensuring stable heating of food products, through the use of accessible components that do not require long-term and difficult technical training, and safety for the user and the environment.

The essence of the invention lies in the fact that an inorganic composition is proposed for use in flameless food heaters, including sodium chloride, copper chloride, aluminum, and water in the following ratio of components, mass. %: sodium chloride 7.0 - 15.4%; copper chloride 8.9 - 18.9%; aluminum 2.8 - 6.0%; water 59.8 - 81.0%.

In table Table 1 shows the compositions of inorganic compositions for use in flameless food heaters.

The inorganic composition for use in flameless food heaters includes sodium chloride, copper chloride, aluminum, and water. Component ratio, mass. %: sodium chloride 7.0 - 15.4%; copper chloride 8.9 - 18.9%; aluminum 2.8 - 6.0%; water 59.8 - 81.0%.

An inorganic composition for use in flameless food heaters works as follows: the components of the mixture are placed in a special pocket (heating element) made of porous non-woven material to retain reaction products and ease of use. The heating element is placed in an outer durable bag consisting of PE/PA. When water is added to the system, the redox process of aluminum oxidation begins, which is accompanied by the release of heat sufficient to heat food products weighing 250-350 g to 53-60 degrees. Due to the formation of metals in the system, an increase in the duration of the heating effect of the heating element is observed, and as a result, the temperature in the system is maintained.

The advantages of the proposed composition for carrying out an effective exothermic reaction are as follows: the use of available components that do not require long-term and difficult technical training; safety for the user and the environment; stable operation in the temperature range of 53-97 degrees for 10-14 minutes.

The claimed technical solution is illustrated by examples of experiments using the proposed method.

Example 1.

To test the composition, a device for a flameless food heater was manufactured. To do this, the inorganic composition is placed in a heating element, which is a non-woven material made in the form of a pocket measuring 8*20 mm. Next, the heating element is placed in a durable outer bag made of PE/PA.

The inorganic composition is prepared as follows (composition 1 of Table 1): sodium chloride 11.24 wt. is mixed. %, copper chloride 11.24 wt. %, aluminum 4.49 wt. %. Water 73.03 wt. is added to the system. %. The system warms up within 2-3 seconds.

The following temperature values are observed in a given system:

Reaction time, min System heating temperature (solution), °C 4 79 8 65 14 59

Example 2.

The BNP device is manufactured similarly to example 1.

The inorganic composition is prepared as follows (composition 3 of Table 1): sodium chloride 12.17 wt. is mixed. %, copper chloride 14.81 wt. %, aluminum 4.23 wt. %. Water 68.78 wt is added to the system. %. The system warms up within 2-3 seconds.

The following temperature values are observed in a given system:

Reaction time, min System heating temperature (solution), °C 4 79 8 70 14 60

Example 3.

The BNP device is manufactured similarly to example 1.

The inorganic composition is prepared as follows (composition 5 of Table 1): sodium chloride 10.11 wt. is mixed. %, copper chloride 12.36 wt. %, aluminum 4.49 wt. %. Water 73.03 wt. is added to the system. %. The system warms up within 2-3 seconds.

The following temperature values are observed in a given system:

Reaction time, min System heating temperature (solution), °C 4 82 8 72 14 58

Example 4.

The BNP device is manufactured similarly to example 1.

The inorganic composition is prepared as follows (composition 6 of Table 1): sodium chloride 8.62 wt. is mixed. %, copper chloride 12.64 wt. %, aluminum 4.02 wt. %. Water 74.71 wt. is added to the system. %. The system warms up within 2-3 seconds.

The following temperature values are observed in a given system:

Reaction time, min System heating temperature (solution), °C 4 87 8 76 14 65

Example 5.

The BNP device is manufactured similarly to example 1.

The inorganic composition is prepared as follows (composition 2 of Table 1): sodium chloride 9.14 wt. is mixed. %, copper chloride 11.17 wt. %, aluminum 3.55 wt. %. Water 76.14 wt is added to the system. %. The system warms up within 2-3 seconds.

The following temperature values are observed in a given system:

Reaction time, min System heating temperature (solution), °C 4 77 8 67 14 57

Example 6.

The BNP device is manufactured similarly to example 1.

The inorganic composition is prepared as follows (composition 4 of Table 1): sodium chloride 7.29 wt. is mixed. %, copper chloride 8.91 wt. %, aluminum 2.83 wt. %. Water 80.97 wt is added to the system. %. The system warms up within 2-3 seconds.

The following temperature values are observed in a given system:

Reaction time, min System heating temperature (solution), °C 4 78 8 71 14 66

Example 7.

The BNP device is manufactured similarly to example 1.

The inorganic composition is prepared as follows (composition 7 of Table 1): sodium chloride 15.38 wt. is mixed. %, copper chloride 18.8 wt. %, aluminum 5.98 wt. %. Water is added to the system 59.83 wt. %. The system warms up within 2-3 seconds.

The following temperature values are observed in a given system:

Reaction time, min System heating temperature (solution), °C 4 90 8 79 14 58

Example 8.

The BNP device is manufactured similarly to example 1.

The inorganic composition is prepared as follows (composition 8 of Table 1): sodium chloride 10.17 wt. is mixed. %, copper chloride 12.43 wt. %, aluminum 3.95 wt. %. Water 73.45 wt is added to the system. %. The system warms up within 2-3 seconds.

The following temperature values are observed in a given system:

Reaction time, min System heating temperature (solution), °C 4 up to 93 8 84 14 75

Example 9.

The inorganic composition and BNP device are prepared according to example 8; additionally, a heated product weighing 340 g is placed in the outer bag, placing it on the surface of the heating element. 13 minutes after activation of the composition, the product is removed from the bag and its heating temperature is measured, which is 56°C.

From Table 1, compositions 2,5,8,9 were studied with the same amount of reagents I, II, III, but different amounts of added reagent IV. Experiments have shown that the composition is most effective when adding 73.45 wt. % water.

Thus, the studied samples (examples 1-8) showed that the optimal ratio of components would be composition 8 from table. 1. The heating temperature of the system after 8 minutes of operation is in the range of 84 degrees. The experiments were carried out without food in the outer bag; the results obtained are valid only for the pure activated composition.

Compared with the known solution, the developed inorganic composition for efficient heat dissipation ensures stable heating of food products through the use of readily available components that do not require long-term and difficult technical training, and is safe for the user and the environment.

Table 1 No. Components Weight, g Weight, % Reaction temperature after 8 minutes 1 I 20 11.24 65 II 20 11.24 III 8 4.49 IV 130 73.03 2 I 18 9.14 67 II 22 11.17 III 7 3.55 IV 150 76.14 3 I 23 12.17 70 II 28 14.82 III 8 4.23 IV 130 68.78 4 I 18 7.29 71 II 22 8.91 III 7 2.83 IV 200 80.97 5 I 18 10.11 72 II 22 12.36 III 8 4.5 IV 130 73.03 6 I 15 8.62 76 II 22 12.64 III 7 4.02 IV 130 74.72 7 I 18 15.4 79 II 22 18.79 III 7 5.98 IV 70 59.83 8 I 18 10.17 84 II 22 12.43 III 7 3.95 IV 130 73.45

Compounds: I - Sodium chloride; II - Copper chloride; III - Aluminum; IV - Water

Claims (1)

Inorganic composition for use in flameless food heaters, including sodium chloride, copper chloride, aluminum, and water in the following ratio of components, mass. %: sodium chloride 7.0–15.4; copper chloride 8.9–18.9; aluminum 2.8–6.0; water 59.8–81.0.