JPH0535751B2 - - Google Patents

Description

Detailed Description of the Invention (Field of Industrial Application) The present invention relates to a method for appropriately delaying a digestive reaction when water and calcium oxide are mixed and a digestive reaction is caused to occur in the calcium oxide. be.

(Prior Art) In recent years, instant foods such as instant noodles have become very popular due to their ease of preparation, and a wide variety of instant foods are on the market.

However, since most of these instant foods require boiling water or heat to cook, they have the inconvenience of not being able to be cooked in a place without a heat source such as fire or electricity. There was a desire to develop a simple heating device that does not use heat sources such as fire or electricity.

Against this background, in recent years, attempts have been made to utilize the reaction heat accompanying the digestive reaction between water and calcium oxide as a heat source.

However, in such a heating device that utilizes the reaction heat accompanying the digestive reaction with calcium oxide, if the properties of calcium oxide are such that the digestive reaction occurs instantaneously when mixed with water, After adding water to calcium oxide, an exothermic reaction starts before it is ready for cooking, which is not only very dangerous when handling it, but also before the water has completely permeated the calcium oxide. However, problems such as an exothermic reaction occurring only in the surface layer of the calcium oxide and the evaporation of the water used to generate the digestion reaction result in a large amount of unreacted calcium oxide, making it impossible to obtain a sufficient amount of heat. Ta.

(Purpose of the Invention) Therefore, the present invention aims to improve the efficiency of digestion by appropriately delaying the digestion reaction of calcium oxide, especially when calcium oxide has the property of instantaneously causing a digestion reaction when mixed with water. In addition to improving handling when using the reaction heat accompanying the reaction as a heat source for heating,
This was done with the intention of proposing a method for delaying the digestion reaction of calcium oxide, which would increase calorific value and improve thermal efficiency.

(Means for Achieving the Object) As a means for achieving the above object, the present invention provides the following steps: Calcium oxide obtained by calcining limestone without adding additives such as salt is used as the calcium oxide, and the amount of water to be mixed with the calcium oxide is determined by the chemical reaction formula between the calcium oxide and water. 1.0 to 2.5 times the theoretically required amount specified based on It is characterized by

(Function) In the present invention, the following effects can be obtained by the above means.

Calcium oxide is obtained by calcining limestone without adding additives such as salt, so it has the property of instantly causing a digestive reaction and generating heat of reaction after mixing with water. Nevertheless, the reaction rate of the digestion reaction will be retarded by the action of retarders consisting of monohydric, dihydric or trihydric alcohols or mixtures thereof.

The amount of water that contributes to the reaction with calcium oxide is the amount of water specified based on the digestion reaction equation for both.
Since it is set to be 1.0 to 2.5 times, the above-mentioned digestion reaction is carried out properly, and the wasted amount of heat consumed in raising the temperature of water that does not contribute to the digestion reaction among the generated reaction heat is reduced as much as possible.

(Effects of the Invention) Therefore, according to the method for delaying the digestive reaction of calcium oxide of the present invention, (a) the digestive reaction of calcium oxide can be delayed, so that it is easy to handle, and the calcium oxide as a whole is Since the digestion reaction is delayed until water permeates, the entire calcium oxide can contribute to the exothermic reaction to increase the calorific value. (b) Since a sufficient amount of reaction water is secured, Effects such as the digestion reaction being carried out properly and the amount of heat consumed solely for raising the temperature of water being reduced, and the thermal efficiency being improved accordingly, can be obtained.

(Embodiments) Hereinafter, preferred embodiments of the present invention will be described with reference to FIGS. 1 to 3.

Structure FIG. 1 shows a method in which the method for delaying the digestion reaction of calcium oxide of the present invention is applied to a heating device for cooking instant noodles, in which the reaction heat accompanying the digestion reaction is applied to a heating device for cooking instant noodles. This is the heat generating container of the device.

This heat-generating container 1 has a bottomed cylindrical container body 2 made of a heat insulating material such as expanded polystyrene resin, and a lid 3 that removably covers an upper opening 2a of the container body 2. The inside thereof is a reaction chamber 10 having an appropriate volume.

The bottom 10a of the reaction chamber 10 houses calcium oxide 5, which causes a digestion reaction and generates reaction heat when mixed with water. In this example, calcium oxide 5 was prepared by applying the present invention.
As a method, calcium oxide is used, which is obtained by burning limestone directly in a heavy oil burner or the like without adding any additives such as salt (so-called heavy oil burning method). Note that this calcium oxide 5 is used in the form of powder or granules.

Furthermore, in this example, by applying the present invention, 1 such as ethanol, which acts as a reaction retarder, is added to the reaction water mixed with calcium oxide 5.
Hydrolic alcohols, dihydric alcohols such as propylene glycol, or trihydric alcohols such as glycerin are added and mixed singly or as a mixture thereof. The amount of the reaction retarder added is preferably 5% to 15% by weight, for example in the case of glycerin, based on the amount of reaction water. Further, this reaction retarder can be added to the calcium oxide 5 side, for example, in addition to being mixed into the reaction water as described above.
In addition, when this heating device is used as a heat source for heating food, the properties of the reaction retarder are required to be harmless and to have no bad odor during the reaction.
Examples of monohydric alcohols that satisfy this condition include ethanol, dihydric alcohols such as propylene glycol, and trihydric alcohols such as glycerin.

On the other hand, in the upper part 10b of the reaction chamber 10, an aluminum pot 4 having a suitable depth has a flange 4a at its upper opening, and the flange 4a is placed on a shelf 2b formed at the upper opening 2a of the container body 2. They are attached in such a way that they can be kept relatively airtight while being hooked. Furthermore, inside this pot 4, dried noodles 6 are accommodated.

The depth of the pot 4 is determined by pouring reaction water into the reaction chamber 10 and mixing the reaction water with the calcium oxide 5 to form a slurry mixture 15, as shown in FIG. Also in the state, the mixture 1
5 and the bottom surface 4b of the pot 4 so as to form a space that allows the generation of steam from the mixture 15.

How to Use and Its Effects Next, how to use this heating device and its effects when cooking the dried noodles 6 using this heating device will be explained.

When cooking, first, the lid 3 of the heat-generating container 1 is removed, and the pot 4 is taken out from the heat-generating container 1. Next, water W for cooking is poured into the pot 4 (see Fig. 2), and reaction water to which a retardant has been added and mixed in advance is administered into the reaction chamber 10, and then,
Quickly attach the pot 4 to the container body 2 again, and then attach the lid 3 from above (the state shown in FIG. 2). This completes the cooking operation.

When reaction water is introduced into the reaction chamber 10, the water and calcium oxide 5 are mixed with each other to form a slurry mixture 15, as shown in FIG. CaO + H ₂ O
→Ca(OH) ₂ +15.2Kcal/mol An exothermic reaction takes place based on the reaction formula.

When the reaction temperature rises, the reaction water evaporates due to the reaction heat, steam V is actively generated from the mixture 15, and the inside of the reaction chamber 10 is filled with this steam V. The water vapor V rising above the reaction chamber 10 comes into contact with the outer surfaces of the bottom surface 4b and side surface 4c of the pot 4 and condenses, and the latent heat of condensation causes the pot 4 and the pot 4 to be condensed.
The cooking water W contained therein is heated. In addition, pot 4
Water droplets condensed on the outer surfaces of the bottom surface 4b and side surface 4c fall one after another and contribute to the exothermic reaction again. In this way, the reaction heat of the exothermic reaction is transferred to the mixture 15
When the latent heat of condensation of the water vapor generated from the steam is transferred to the pot 4, the heat transfer coefficient is larger (than Heat transfer coefficient of water vapor h=
4,000 to 15,000 Kcal/m ² hr°C) and has a large heat transfer area, so it has good thermal efficiency and can achieve rapid heating.

The reaction rate of this digestive reaction between calcium oxide 5 and reaction water differs depending on the properties of calcium oxide 5. That is, as in this example, calcium oxide 5
When calcium oxide obtained by the heavy oil boiling method is used, as shown by curve _L1 in Figure 3, an exothermic reaction starts instantaneously after reaction water is mixed with the calcium oxide, and the reaction temperature rises rapidly. As a result, it is dangerous to handle, for example, because high-temperature steam is generated before cooking preparations are complete.

However, in this example, as mentioned above, the present invention is applied and alcohol such as ethanol or propylene glycol is added to the reaction water as a reaction retardant, so even if the reaction water is added to calcium oxide 5, the reaction does not occur instantly. The digestion reaction does not start immediately, and the digestion reaction starts with a predetermined time difference after mixing with the reaction water, as shown by curve _L2 in FIG. According to the experiments of the present inventors,
When 100 g of calcium oxide and 48 g of reaction water are mixed to cause an exothermic reaction, when 4.05 g of ethanol is added as a reaction retardant, the reaction occurs approximately 17 seconds after mixing 5 calcium oxide and the reaction water. is started, propylene glycol 5.15
When 5.3g of glycerin is added, the reaction starts after about 50 seconds, and when 5.30g of glycerin is added, the reaction starts after about 50 seconds.
The reaction started after 23 seconds. Therefore, after pouring the reaction water into the heat-generating container 1, there is enough time for the high-temperature steam V to be generated from the mixture 15, and for this reason, it is possible to attach the pot 4 and the lid 3 after pouring the reaction water. To ensure that cooking preparation work such as cooking work can be carried out reliably and safely.

Furthermore, even if reaction water is mixed with calcium oxide 5 in this way, the digestion reaction between the two does not take place for a predetermined period of time (in other words, until almost all of calcium oxide 5 is mixed with the reaction water, the reaction between the two does not take place). ), the digestion reaction between the reaction water and calcium oxide takes place only in the surface layer of the calcium oxide, and as a result, the reaction water evaporates and a large amount of calcium oxide is produced due to the lack of reaction water. The calcium oxide does not remain in an unreacted state, and the entire calcium oxide contributes to the exothermic reaction, making it possible to increase the calorific value.

Furthermore, in this example, the amount of reaction water to be mixed with calcium oxide 5 was adjusted to the theoretically required amount defined by the above reaction formula (i.e., 1 mol of reaction water per 1 mol of calcium oxide). The ratio is set to 1 to 2.5 times. For this reason,
Even if the water becomes water vapor and scatters due to the exothermic reaction, the amount of reaction water necessary for the above-mentioned digestion reaction is secured until the end of the reaction, and the amount of heat taken away by the water that does not contribute to the above-mentioned digestion reaction is reduced, so that the water temperature quickly increases. The above-mentioned digestive reaction is promoted from the point where the
The reaction temperature is allowed to rise rapidly. Incidentally, according to experiments conducted by the inventors of the present application, the best results were obtained when the mixing ratio of water to calcium oxide was about 1.5 times the theoretically required amount.

Furthermore, in this embodiment, when the pot 4 is attached to the container body 2, the airtightness between the two is relatively maintained.
In the cooking state in which long-use water W and dried noodles 6 are put into the chamber, the airtightness of the reaction chamber 10 is maintained appropriately by the weight of the pot 4, water W, and dried noodles 6, and the increase in internal pressure prevents water vapor from flowing out. Steam pressure is increased. Therefore, the temperature of the water vapor in the reaction chamber 10 is further increased compared to the case where the reaction chamber 10 is open to the atmosphere, and the object to be heated can be heated to a correspondingly high temperature. This is particularly suitable when the heating device of the present invention is used in a place with low atmospheric pressure, such as a mountainous area.

Further, when the digestion reaction in the reaction chamber 10 progresses and the internal pressure of the reaction chamber 10 becomes equal to or higher than a predetermined pressure, the pot 4 is pushed upward by the pressure, the airtightness of the reaction chamber 10 is released, and the reaction chamber 10 is made airtight. This prevents the internal pressure of 10 from increasing further. That is, the pot 4 functions as a kind of safety device against the pressure increase in the reaction chamber 10, and safety in cooking operations is ensured.

[Brief explanation of drawings]

FIG. 1 is a longitudinal cross-sectional view of a heating device to which the method for delaying the digestion reaction of calcium oxide of the present invention is applied, FIG. 2 is a diagram of the cooking state of the instant food shown in FIG. 1, and FIG. FIG. 3 is a progress diagram of a digestive reaction during DESCRIPTION OF SYMBOLS 1... Exothermic container, 2... Container body, 3... Lid, 4... Pot, 5... Calcium oxide, 6... Dry noodles, 10... Reaction chamber, 15... Mixture.

Claims (1)

[Claims] 1. When mixing calcium oxide 5 and water W in the reaction chamber 10 to cause the calcium oxide 5 to undergo a digestive reaction accompanied by reaction heat, limestone is used as the calcium oxide 5 without adding additives such as salt. Calcium oxide obtained by calcination is used, and the amount of water mixed with the calcium oxide 5 is adjusted to the theoretically required amount defined based on the chemical reaction formula between the calcium oxide 5 and water.
1.0 to 2.5 times, and at least one of the above calcium oxide 5 and water contains a monohydric alcohol,
A method for retarding the digestion reaction of calcium oxide, which comprises adding a reaction retarder consisting of a dihydric alcohol, a trihydric alcohol, or a mixture thereof.