JPH0527672B2 - - Google Patents

Description

[Detailed description of the invention]

The present invention relates to a chemical heating element that generates a chain exothermic reaction by adding water, part 1 of the present invention.
Although a simple water heater will be described in detail as an application example, the content of the water heater is of course not limited to water. Examples include well-known ready-to-eat noodles, coffee, curry, soup, and other cooked foods. Conventionally, methods for heating food using chemical heating elements have been disclosed in Japanese Utility Model Application Publication No. 1983-99349 and Japanese Patent Application Publication No. 1983-1999.
Specific proposals can be found in 28436, etc., and Japanese Patent Publication No. 56 (1983) proposed the application of chemical warmers to heating food.
There are proposals such as -165856 and 57-3637. On the other hand, regarding a chemical heating element that reacts with water and has metal powder as one of its basic constituents,
78943, 50-40477, 52-113383, 55-
There have been proposals such as 99544 and 55-135188, and from the standpoint of a thermal energy source, JP-A-57-
123801, US Patent No. 3348919, US Patent No. 3540854, etc. can be found. The present inventor is currently actively researching a chemical heating element that can impart 20 Kcal to a heated object, which is enough heat to raise the temperature of 300 ml of water by approximately 60 degrees.
The present invention was gradually completed. The present invention will be explained below, but even if there is an error in the explanation, it will not diminish the effects of the present invention in any way. The present invention is based on a combination of three or more substances.
It consists of more than one type of chemical exothermic reaction, and as a result of successive chain exothermic reactions, it is characterized by an extremely large amount of thermal energy generated per unit time. It is thought that there are many other substances that make up this chemical heating element other than those mentioned below, but from the standpoint of safety, hygiene, and non-pollution, all substances that are considered poisonous or deleterious substances were excluded from consideration. Regarding the substances constituting the chemical heating element according to the present invention, the known basic exothermic reaction with water will be described below. 1 Reaction of alkaline earth metal oxides "CaO + H ₂ O → Ca (OH ₂ )" An exothermic reaction occurs, and the product shows alkalinity. 2. Anhydrous alkali metal salts "Na ₂ SO ₄ , Na ₂ S ₂ O ₃ , Na ₂ HPO ₄ , Na ₂ CO ₃ " These substances generate heat when forming hydrates. 3 Anhydrous ferric chloride This substance generates heat when it forms a hydrate. The known basic reactions of the constituent substances of this chemical heating element have been described above, and therefore, corresponding effects can be expected even if the exothermic reactions of each single substance are used. However, according to research conducted by the present inventors, even the exothermic reaction of calcium oxide, which is thought to have the greatest potential among exothermic reactions of a single substance, had several drawbacks at the stage of practical application. The theoretical calorific value of calcium oxide is estimated as follows. CaO＋H ₂ O→Ca(OH ₂ ) △HfCaO=−635.1KJ/mol △HfH ₂ O=−285.8KJ/mol △HfCa(OH) ₂ =−986.1KJ/mol Therefore, the calorific value △Hr is as follows Desired. △Hr＝△HfCa(OH) ₂ −(△HfCa＋△HfH ₂ O) = −65.2KJ/mol = −15.6Kcal/mol In other words, if you want to obtain a calorific value of about 20Kcal,
Approximately 71g of calcium oxide is required. This seems to be relatively heavy for a chemical heating element. Currently, the industrially available calcium oxide is quicklime, which has an apparent specific gravity of approximately 1.2.
The theoretical volume of 71 g is estimated to be about 60 cm ³ , but in reality it was even larger due to the presence of coarse particles. Next, after a hydration reaction, the quicklime turned into slaked lime, but at this time, a volumetric expansion phenomenon occurred. In addition, numerous obstacles hindered its practical application, such as the rate of temperature increase and the maximum temperature that were much lower than expected. Thus, in order to put a simple water heater into practical use, it is necessary to increase the density of thermal energy and increase the rate of generation of thermal energy. The present inventor is actively investigating and researching chemical heating elements that can satisfy these two conditions, and as described in the following examples,
Little by little, they were able to complete a simple water heater. In addition, the structure of the simple water heater used for water temperature measurement in the reference examples and examples described in detail from now on was all the same structure as the attached drawing. Reference example: 45g of lightly calcined dolomite (MgO:CaO=3:7 manufactured by Wakui Chemical Co., Ltd., hereinafter the same) as chemical heating element No. 1 in part A of a simple water heater, and lightly calcined dolomite as No. 2 in the upper layer. Metal aluminum powder of 35g and 200 mesh or less in the lower layer (Minato Aluminum Industry Co., Ltd.)
Manufactured by Co., Ltd. (hereinafter referred to as Al powder) 10g, No. 3
As No. 4, 45 g of granulated quicklime (manufactured by Wakui Chemical Co., Ltd., hereinafter the same), 35 g of granulated quicklime in the upper layer as No. 4,
Metal aluminum powder of less than 200 mesh in the lower layer
10g, 25g of granulated quicklime in the upper layer as No. 5, in the middle layer
10g of metal aluminum powder of 200 mesh or less,
Mix 10g of granulated quicklime as a chemical heating element in the lower layer, then add 330ml of 18℃ water to container 1 of each simple water heater.
After pouring 70 ml of 18°C water into container 3, the upper opening was immediately covered with aluminum foil and changes in water temperature were measured. The composition of the chemical heating elements is shown in Table 1, and the water temperature measurement results are shown in Table 1-1.

【table】

[Table] As is clear from the measurement results in Table-1-1, No.5
The amount of heat generated by the chemical heating element was the largest, but it was still insufficient for a simple water heater. However, it was thought that a composition in which at least the Al powder is wrapped in some kind of substance would be suitable for obtaining a larger calorific value. The present inventor has researched and researched a 3rd class substance that has a material composition of lightly calcined dolomite or granulated quicklime as a 1st class substance and Al powder as a 2nd class substance, and that provides higher heating element reactivity than the reference example. As a result of proceeding with the process, firstly, sodium percarbonate (Na ₂ CO ₃
1.5H ₂ O) and sodium perborate (NaBO ₂
They discovered that a substance called H ₂ O) (both manufactured by Mitsubishi Gas Chemical Co., Ltd.) was extremely effective. Next, the effectiveness of sodium chloride (NaCl) and sodium carbonate (Na ₂ CO ₃ ) (both manufactured by Wako Pure Chemical Industries, Ltd.) was confirmed. Example 1 Lightly calcined dolomite 25 is used as the upper layer in part A of a simple water heater.
g, 10g of Al powder of 200 mesh or less is used as a common component in the middle layer, and chemical heating element No. 6 is used in the lower layer.
Na ₂ CO ₃・1.5H ₂ O5g, NaBO ₂・ as No.7
5g of H ₂ O, as No. 8 NaCl 10g, as No. 9
Mix chemical heating elements each containing 10g of Na ₂ CO ₃ , then pour 330ml of 18°C water into each container 1 and 70ml of 18°C water into container 3, then immediately cover the top opening with aluminum foil. The water temperature was measured by covering it with water. The composition of these chemical heating elements is shown in Table 2, and the water temperature measurement results are shown in Table 2-1.

【table】

[Table] Comparing the above reference example and this Example 1, the third
It is obvious that the amount of heat generated is increased by mixing similar substances. The results confirmed the possibility that other effective substances exist, but before starting a wide-ranging search for these substances, it is important to consider the basic issues of the blending ratio of each layer and the composition of each layer. We investigated the correlation between substances and water temperature changes. Example 2 The amount of lightly calcined dolomite in the upper layer was 15g, 25g, and 35g.
g, the amount of Al powder of 200 mesh or less in the middle layer is 5
The amount of _Na2CO3・_1.5H2O in the lower layer was changed to 5g, 10g, and 15g, and _a chemical heating element was added, and the change in water temperature was measured in the same manner as in Example 1. . The relationship between the numbers of these chemical heating elements and their blending ratios is shown in Table 3, and the water temperature measurement results are shown in Table 3-1.

【table】

【table】

[Table] From this result, it can be understood that by varying the blending ratio of the three types of the same substances, it is possible to freely control the water temperature increase rate and the maximum temperature reached. Additionally, the following general characteristics can be discerned. B Correlation between the amount of lightly calcined dolomite and exothermic reaction Comparing Nos. 15, 17, and 18, the initial temperature rise rate of No. 17, which has the least amount of lightly calcined dolomite, is a little slow, but the maximum temperature reached for all of them is , have reached almost the same level. In other words, the amount of lightly calcined dolomite seems to regulate the initial temperature rise rate. (b) Correlation between the amount of 200 mesh Al powder and exothermic reaction Comparing Nos. 10, 11, and 12, the highest temperature reached is higher with a larger amount of Al powder, but conversely, the initial temperature rise rate is slower. ing. (c) Correlation between the amount of Na ₂ CO ₃・1.5H ₂ O and the exothermic reaction When comparing Nos. 10, 15, and 16 with 5 g of Al powder, the amount of Na ₂ CO ₃・1.5H ₂ O is higher in the initial There is a linear correlation between the temperature increase rate and the maximum temperature reached, but when comparing Nos. 11, 13, and 14 with an Al powder amount of 10 g, No. 13 has the highest exothermic reaction in terms of initial temperature rise rate and maximum temperature. A unique correlation can be seen in that it shows activity. We decided to conduct future research and research using the same quantitative ratio as chemical heating element No. 13, and in the next example, we will investigate the composition of each layer of the three substances: light calcined dolomite, Al powder, and Na ₂ CO ₃・1.5H ₂ O. The correlation between position and exothermic reaction was investigated. Example 3 Weighed 25 g of lightly calcined dolomite, 10 g of Al powder of 200 mesh or less, and 10 g of Na ₂ CO ₃ .1.5H ₂ O, and produced a chemical heating element according to the layer position relationship shown in Table 4. Changes in water temperature were measured using a similar method. The relationship between the number of these chemical heating elements and the position of the blended layer is shown in Table 4, and the water temperature measurement results are shown in Table 4-1.

【table】

[Table] As a result, except for the fact that the initial temperature rise rate of the chemical heating element at the compound layer position in No. 20 was slightly slower, all of them showed almost the same exothermic activity, including the maximum temperature reached, and each substance The position of the compound layer is not particularly limited. When we inspected part A of the simple water heater after the exothermic reaction was completed, we found that the various substances were naturally mixed together due to the rapid exothermic reaction and the ejection of steam gas. There appears to be no correlation between layer position and exothermic reaction. As clarified in Example 1, it is a neutral salt.
Based on the fact that NaCl activates an exothermic reaction, we first conducted a wide range of research on substances, and in the next step we narrowed down the research area and selected all the substances that activate the reaction. Summer. Example 4 25g of granulated quicklime was used in the upper layer, and up to 10g of Al powder of 200 mesh or less was used in the middle layer.For the 10g of compounded material (manufactured by Wako Pure Chemical Industries, Ltd.) in the lower layer, the mixture was as shown in Table 5 below. Chemical heating elements were manufactured, and changes in water temperature were measured in the same manner as in Example 1, and the results are shown in Table 5-1. However, among the substances listed in Table 5, LiCl was manufactured by Nippon Chemical Industry Co., Ltd., and persulfate was manufactured by Mitsubishi Gas Chemical Co., Ltd.

【table】

【table】

【table】

[Table] When compared with reference example chemical heating element No. 4 or No. 5, the ranking of substances with highly activated exothermic reaction characteristics by blending with Class 3 substances is as follows: It can be organized like this. 1st place substance group “K ₂ CO ₃ , KHCO ₃ , K ₂ SO ₃ ” Gives the highest activity in terms of initial temperature increase rate, with a 5 minute value exceeding 70℃ and a maximum temperature exceeding 80℃ substance. 2nd place substance group ``Na ₂ SO ₄ , K ₂ SO ₄ '' Substances whose maximum temperature exceeds 80℃. Third substance group "KCl, _NaNO3 , _KNO3 , _{KH2PO4 , K3PO4} " Substances with a maximum temperature of 70 to ₈₀ °C. 4th place substance group "K ₂ HPO ₄ , FeCl ₃ " Substances with maximum temperature reaching 60-70℃. 5th place substance "K (CH ₃ COO)" A substance with a maximum temperature of 50-60℃. The 6th substance group “Li ₂ CO ₃ , LiCl, (NH ₄ ) ₂ S ₂ O ₈ , Na ₂ S ₂ O ₈ ,
MgCl ₂ , MgSO ₄ , CaCl ₂ , Al ₂ (SO ₄ ) ₃ , AlK
(SO ₄ ) ₂ ” A substance that does not impart activity at all, or on the contrary, has decreased activity. Based on the results of Example 4, we narrowed down the search range for Class 3 substances to compounds of Na and K, and conducted further research. Example 5 According to the same method as in Example 4, water temperature was measured using a chemical heating element having the formulation shown in Table 6, and the results are shown in Table 6-1.

【table】

[Table] The results were summarized in the same manner as in Example 4. 1st place substance: “There are no substances that correspond to this.” 2nd place: substance group: “NaHSO ₃ , Na ₂ S ₂ O ₅ ” 3rd place: substance group: “NaHCO ₃ , Na ₂ SO ₃ , Na ₂ S ₂ O ₃ , K ₂ S ₂ O ₅ ” 4th place substance group ``There are no substances that correspond to this.'' 5th place substance group ``NaBr, NaBrO ₃ , Na ₂ SiO ₃ , Na ₂ B ₄ O ₇ ,KBr,
K ₂ S ₂ O ₈ ” 6th place substance `` K <sub>2</sub> S <sub>2</sub> O <sub>7</sub> , KHSO <sub>4</sub> '' The reason why potassium pyrosulfate did not impart any activity is thought to be because the substance was in the form of a solid lump. It will be done. When the results of Examples 4 and 5 are combined with the results of Example 1, the results appear to be as follows. Number 1 substance group: Most active “Na <sub>2</sub> CO <sub>3</sub> , Na <sub>2</sub> CO <sub>3</sub>・1.5H <sub>2</sub> O, K <sub>2</sub> CO <sub>3</sub> ,
KHCO <sub>3</sub> , K <sub>2</sub> SO <sub>3</sub> ” 2nd substance group: Above 80℃ “Na <sub>2</sub> SO <sub>4</sub> , NaHSO <sub>3</sub> , Na <sub>2</sub> S <sub>2</sub> O <sub>5</sub> , NaBO <sub>2</sub>・
H <sub>2</sub> O, K <sub>2</sub> SO <sub>4</sub> 3rd place substance group: 70-80℃ ``NaSO ₃ , NaHCO ₃ , Na ₂ SO ₃ , Na ₂ S ₂ O ₃ ,
KCl, KNO ₃ , K ₂ S ₂ O ₅ , KH ₂ PO ₄ , K ₃ PO ₄ 4th place substance group: 60-70℃ ``NaCl, K ₂ HPO ₄ , FeCl ₃ 5th place substance group :60 _~ 60 _℃ "NaBr, _NaBrO3 , _{Na2SiO3 , Na2B4O7} , KBr,
K ₂ S ₂ O ₈ , K (CH ₃ COO)” 6th substance group: No effect “Na ₂ S ₂ O ₈ , KHSO ₄ , K ₂ S ₂ O ₇ , Li ₂ CO ₃ , LiCl,
( _NH4 ) _2S2O8 , _{MgCl2 , MgSO4} , _{CaCl2 , Al2}
(SO ₄ ) ₃ , AlK(SO ₄ ) ₂ ” Up to Example 5, research had been conducted with the particle size of Al powder fixed at 200 mesh or less.
In Example 6, the correlation between the particle size of Al powder and the exothermic reaction was investigated. Example 6 25g of granulated quicklime in the upper layer, 10g of Al powder in the middle layer,
The chemical heating elements shown in Table 7 were manufactured using the basic composition of Na ₂ CO ₃ and 1.5H ₂ O in the lower layer and five different particle sizes of Al powder, and the changes in water temperature were performed in the same manner as in Example 1. was measured, and the results shown in Table 7-1 were obtained.

【table】

[Table] From the results of Example 6, it became clear that Al powder with a particle size of 30 to 100 mesh or less showed a practically high exothermic reaction activity. Next, research has focused on lightly calcined dolomite and granulated quicklime as Class 1 substances, and in the following Example 7, the exothermic reaction activity of magnesium oxide and calcium hydroxide was investigated. Example 7 The upper layer contains 25 g of magnesium oxide (manufactured by Wako Pure Chemical Industries, Ltd.) as chemical heating element No. 66, and 25 g of granulated slaked lime (manufactured by Wakui Chemical Co., Ltd.) as No. 67, and the middle layer contains 200 mesh or less. 10g of Al powder, lower layer of
A chemical heating element was manufactured using 10 g of Na ₂ CO ₃ .1.5H ₂ O as a common composition, and changes in water temperature were measured in the same manner as in Example 1, and the results shown in Table 8-1 were obtained.

【table】

[Table] Comparing this result with the high activity of the chemical heating element using lightly calcined dolomite, it can be understood that it is the calcium compound that provides the activity, and therefore the magnesium oxide in the lightly calcined dolomite. It is preferable that the components do not increase too much. Next, we conducted research on substances other than aluminum metal powder as Class 2 substances. Its substance is metallic magnesium powder (purity 97
%, particle size 40-50 mesh), metallic zinc powder (purity
85%, particle size 300 mesh), metal silicon powder (98% purity, particle size 100 mesh), metal tin powder (purity
95%, particle size 200 mesh) (all of the above are from Wako Pure Chemical Industries)
Co., Ltd.) was mixed with light calcined dolomite as the 1st class substance and Na ₂ CO ₃ .1.5H ₂ O as the 3rd class substance, and the results showed no exothermic reaction activity at all. Metallic zinc powder with even higher purity (99.8% purity,
Particle size: 200 mesh, manufactured by Mitsui Kinzoku Kogyo Co., Ltd.) Metallic silicon powder (purity: 99.9%, particle size: 200 mesh, manufactured by Rare Metallic Co., Ltd.), Metallic iron powder (purity: 99.9%,
Particle size: 200 mesh, manufactured by Showa Denko Co., Ltd.), granulated quicklime as a Class 1 substance, and granulated quicklime as a Class 3 substance.
The results of investigations using Na ₂ CO ₃ , Na ₂ S ₂ O ₈ , KCl, and (NH ₄ ) ₂ S ₂ O ₈ showed no exothermic reaction activity at all. In the above examples, we investigated and researched the basic characteristics of chemical heating elements immediately after manufacturing them, but when applied to simple water heaters, a particular problem is the decrease in exothermic reaction activity due to the environmental atmosphere. This is the possibility of occurrence. Therefore, the environmental test conditions were a dry bulb temperature of 60℃,
A simple water heater containing a chemical heating element was stored in a high-temperature, high-humidity tester with a wet bulb temperature of 58°C for 24 hours to investigate changes in exothermic reaction characteristics. Example 8 The entire containers 1, 2, and 3 of a simple water heater were covered with commercially available household aluminum foil, and the edges of the container 3 were wrapped with adhesive tape.
Then, the entire portable water heater was placed in a polyethylene bag and the opening was closed with a rubber band. The simple water heater manufactured in this way can be used for 24 hours.
After being subjected to a high temperature humidification test under the conditions described above, changes in water temperature were measured in the same manner as in Example 1 using 20°C water. Table 9 shows the composition of the chemical heating element used for this.
The results obtained are shown in Table 9-1.

【table】

[Table] Among chemical heating elements No. 68 to No. 70, the initial temperature increase rate of No. 69 is slightly lower than that of No. 13 or 23, but the maximum temperature has hardly changed. figure,
All exhibited excellent environmental resistance. On the other hand, chemical heating elements No. 71 and 72, which were composed of Al powder and sodium carbonate, showed no exothermic reaction activity at all. As described above, the present invention uses lightly calcined dolomite, quicklime, and slaked lime as the first class substances, and
Al powder with a particle size of 100 mesh or less is classified as a Class 2 substance, and sodium or potassium bromate, bromate, hydrochloride, sulfate, nitrate, carbonate, borate, phosphate, silicic acid Salt, anhydrous acetate salt, or ferric chloride anhydrous salt is a Class 3 substance, and it is a necessary condition that it is composed of three or more substances with each substance as an essential component, and at the same time, each substance It is non-poisonous, non-polluting, and has no harmful properties.
Also, it is characterized by high safety when viewed as a water heater. The most active chemical heating element according to the present invention is composed of, for example, granulated quicklime, Al powder of less than 200 mesh, and sodium carbonate, but the composition of these materials and the extremely high exothermic reactivity with water are as follows. It is understood as follows. First, as a first exothermic reaction, granulated quicklime and sodium carbonate are hydrated with water and generate heat, preheating the entire chemical heating element. Second, the oxidized layer on the surface of the Al powder is eluted by the alkali. Thirdly, a water decomposition reaction occurs due to the Al powder.
At this time, since the second and third reactions are preheated by the first reaction, it is thought that they occur within an extremely short period of time. As described above, the present chemical heating element is characterized in that, unlike the reaction of conventional chemical heating elements, all of the blended substances cause an exothermic reaction, and the reaction is chain-like. As described in detail above, the present invention makes it possible to obtain hot water immediately at any time and in any situation as long as there is water. It makes a huge contribution to the diet of the people in mines, on ships, in cars, outdoors, etc., where there is a possibility of food loss. Reference book 1 Chemistry Handbook Basic Edition, (published by Maruzen Co., Ltd.) 2 New edition of Inorganic Chemistry Volumes 1, 2, 2 (Toshizo Chiya)
Author)

[Brief explanation of the drawing]

This drawing shows a central vertical sectional view of a simple water heater. 1... Inner container made of metal, 2... Intermediate container made of paper, 3... Outer container made of paper, 4, 5, 6... Chemical heating element, 7... Open cell plastic foam,
8...Water infiltration hole, 9...Water infiltration hole and water permeable membrane.

Claims (1)

[Scope of Claims] 1. A co-fired product of 30% or less magnesium oxide and 70% or more calcium oxide, an alkaline earth metal element compound consisting of calcium oxide and calcium hydroxide as the first class substance, and metallic aluminum powder A chemical heating element characterized in that it is composed of three or more kinds of substances, each of which is a Class 2 substance and an alkali metal element compound or a metal element compound is a Class 3 substance, each of which is an essential component. 2. The chemical heating element according to claim 1, wherein the metal aluminum powder has a particle size of 30 to 100 mesh. 3 bromate, bromate, hydrochloride, sulfate of sodium or potassium alkali metal element compound;
Powdered or particulate anhydrous salts of nitrates, carbonates, borates, phosphates, silicates, acetates, and the metal element compound is a powdered or particulate anhydrous salt of ferric chloride. A chemical heating element according to scope 1. 4 Sulfates are pyrosulfites, thiosulfates, sulfates, sulfites, and bisulfites, carbonates are carbonates, hydrogen carbonates, and percarbonates, and borates are borates and perborates. 4. The chemical heating element according to claim 3, which is an acid salt, and the phosphates are phosphate trisalt, phosphate disalt, or phosphate monosalt.