JPH0471145B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION Field of Industrial Application The present invention converts low-grade thermal energy sources, such as Mekage and Hinata, which have infinite heat but cannot be used because the temperature difference is small, into high-grade energy sources. Regarding heat pumps for converting heat into heat sources.

Structure of a conventional example and its problems The basic structure of a chemical heat pump consists of an absorption-regenerator 1, an evaporator-condenser 2, and a valve 3 shown in FIG. The absorption-regenerator 1 is filled with an absorbent, and the evaporator-condenser 2 is filled with a refrigerant. Hereinafter, a case where zeolite is used as an absorbent and water is used as a refrigerant will be explained as an example. It allows water vapor to flow in and out between containers, and utilizes the accompanying thermal energy.

Conventionally, two types of operation methods (generally referred to as type 1 and type 2) have been considered for this operation. The principle of operation of these devices is illustrated in FIGS. 2 and 3. Figure 2 shows Type 1 method and Type 3 method.
The figure shows the second type system. In both figures, the horizontal axis shows temperature and the vertical axis shows water vapor pressure inside the container. Numbers 1 and 2 added to the curve are absorption-
It corresponds to the vapor pressure in the regenerator 1 and the evaporator-condenser 2, that is, the vapor pressure of zeolite and water. In addition, each method consists of two processes,
The direction of movement of water vapor for each process is shown by a single line arrow, and the direction of movement of thermal energy is shown by a double line arrow. Thermal energy is low-grade energy that is relatively close to room temperature, and Q is high-grade energy that is far from room temperature.
Indicated by

Figure 2 shows that the type 1 chemical heat pump absorbs high-temperature thermal energy _Q1 .
By supplying it to the zeolite in the regenerator, water is condensed in the evaporator-absorber (movement of water vapor from a to b in the figure), thereby obtaining lower energy q ₁ . In the next process, the dried zeolite forcibly absorbs water (water vapor moves from c to d in the figure), and at this time, high-grade cold heat Q ₂ and low-grade heat q ₂ are obtained. It operates by repeating the above two processes.

Next, in Figure 3, for the second type chemical heat pump, the zeolite is regenerated by high-grade cold heat Q ₃ (steam moves from e to f in the figure), and then low-grade heat q ₄ is applied to move from g to h in the figure. It moves water vapor to obtain high-temperature heat _Q4 .

Considering the above from a different angle, in one of the two processes included in each method, heat (water vapor) flows from the higher temperature to the lower temperature. Therefore, if you want to obtain high-grade cold energy, you need high-grade heat energy, and if you want to obtain high-grade heat energy, you need high-grade cold energy.

Purpose of the Invention The present invention is directed to the type 1 and type 2 operation methods that were conventional
By constructing a new chemical heat pump instead of seeds, the purpose is to obtain high-grade thermal energy or cold energy by using low-grade thermal energy or cold energy.

Structure of the Invention In the present invention, an evaporator-condenser 2 is filled with a substance whose solubility in water rapidly increases after a certain temperature, such as carbamate ester, especially ethyl carbamate, etc. is a chemical heat pump that is filled with a well-known absorbent (calcium chloride, zeolite, silica gel, etc.) and water, evacuates the system, removes air, and seals the system.

An example using ethyl carbamate as an example of the carbamate ester will be described. Ethyl carbamate has a melting point of about 50°C and is slightly soluble in water even at temperatures below the melting point. At temperatures above the melting point, its solubility approaches infinity and it easily dissolves in water. As the solubility of ethyl carbamate in water increases, the saturated water vapor pressure of the solution stops increasing. As a result, the vapor pressure-temperature curve exhibits a shape bent toward the lower pressure side near the melting point of ethyl carbamate.

Description of Examples Examples were carried out using a chemical heat pump having the configuration shown in FIG. Absorption-regenerator 1 contains 10% of silica gel
200 g of water-containing material was charged, and the evaporator-condenser 2 was charged with 1 kg of ethyl carbamate. Ethyl carbamate melts and becomes a liquid at around 50℃. Along with this phase change, the solubility of the refrigerant, water, increases rapidly, and the concentration of ethyl carbamate dissolved in water increases significantly. The vapor pressure will no longer increase. As a result, as shown in curve 2 in Figure 4 of the specification, vapor pressure-temperature curves are obtained that are bent downward near the melting point of the carbamate ester, and as shown in Figure 4, they intersect with each other. Combinations with vapor pressure-temperature characteristics are possible. In a chemical heat pump with such a configuration, the cold source (q ₆ in Figure 4) has a temperature lower than the intersection, and the heat source (Figure 4
Figure q ₅ ) By operating at a temperature higher than the intersection point, a heat pump that has never existed before can obtain both heat output at a temperature lower than the cold source (Q ₆ ) and high heat output at a temperature higher than the heat source (Q ₅ ). can be configured. The relationship between vapor pressure and temperature in each container is shown by curves 1 and 2 in FIG. The operating principle of the present invention will be explained below with reference to FIG.
In the first step, absorption-regenerator 1 is heated to 70℃ (q ₅ )
Then, water vapor flows with heat from i to j, and as a result, the evaporator-condenser 2 generates heat (Q ₅ ) at 100°C.
In the second step, when valve 3 is closed and the device is returned to room temperature and valve 3 is opened, evaporator-condenser 2 is heated to 5°C.
(Q ₆ ), and the absorber-regenerator 1 released heat (q ₆ ) of 30°C. To summarize the above, a low-grade heat source (q ₅ ) and a low-grade cold source (q ₆ ) are converted into high-grade heat (Q ₅ ) and high-grade cold energy (Q ₆ ). In the case of this example, the temperature difference representing the value of the energy source has expanded from 70-30 = 40°C to 100-5 = 95°C, but as an example of development, it is natural that multiple units of the present invention were connected. In this case, the magnification rate of the temperature difference can be further improved.

Effects of the Invention As described above, the chemical heat pump of the present invention has the effect of converting low-quality heat and cold energy into high-quality heat and cold energy. Furthermore, if multiple units of the present invention are connected to improve energy quality, it is possible to effectively use energy that is an infinite energy source such as sunlight and sunlight but is of low quality and cannot be used. Summer.

[Brief explanation of drawings]

Figure 1 is a configuration diagram of a chemical heat pump, Figure 2
The diagram shows the operating principle of a first-class chemical heat pump.
FIG. 3 is a diagram of the operating principle of a second type chemical heat pump, and FIG. 4 is a diagram of the operating principle of a chemical heat pump according to an embodiment of the present invention. 1... Absorption-regenerator, 2... Evaporation-condenser, 3
……valve.

Claims (1)

[Claims] 1 At least two tanks are in communication with each other so that they can be opened and closed, the curves of the refrigerant vapor pressure on the filling material in each tank versus temperature intersect, and at least one tank is filled with carbamate ester. A chemical heat pump featuring: