JPH09318182A - Absorption room cooler - Google Patents

Abstract

PROBLEM TO BE SOLVED: To facilitate air-cooling of a condenser and make the corrosion- resistant technique of a high grade unnecessary by employing hydrofluorocarbon refrigerant having no problem of destroying ozone layer as refrigerant. SOLUTION: Thin absorbing solution is supplied from an absorber 5 into a reproducer 3 through a solution heat exchanger 10 and a solution pump 7 to evaporate refrigerant in the regenerator 3 by heating the thin absorbing solution by heating gas supplied from an external source and condense the absorbing solution. On the other hand, the reproducer 3 is provided with a fractionater 8 at the outlet port thereof to liquefy evaporated refrigerant supplied from the regenerator 3 into the condenser 4 through the fractionater 8. Further, the refrigerant, liquefied in the condenser 4, is supplied into the evaporator 6 of an indoor machine 2 through an expansion valve 11 and is vaporized in the evaporator 6 by depriving heat of a room. The vaporized refrigerant is supplied from the evaporator 6 into the absorber 5 of an outdoor machine 1 while thick absorbing solution is supplied from the generator 3. In this case, hydrofluorocarbon is used as the refrigerant.

Description

Detailed Description of the Invention

[0001]

TECHNICAL FIELD The present invention relates to an absorption type air conditioner.

[0002]

2. Description of the Related Art Absorption type air conditioners function as a compressor in vapor compression refrigeration to absorb a refrigerant by an absorbing solution (absorbing liquid) in an absorber and to condense the absorbing solution in a regenerator (generator). This is done by separating the refrigerant. For air conditioning,
A combination of water as a refrigerant and lithium bromide as an absorbing liquid,
A combination using ammonia as a refrigerant and water as an absorbing liquid has been studied (see Japanese Patent Publication No. 5-28752). Further, a combination of using CFC as a refrigerant and tetraethylene glycol dimethyl ether as an absorbing liquid has also been studied (see Japanese Patent Publication No. 63-56918).

[0003]

However, in the case of a water-lithium bromide absorption type air conditioner, since water is used as a refrigerant, the temperature is 0.degree.
The following cooling is not possible, it is difficult to cool the condenser by air because the solubility of lithium bromide in water is limited, and high corrosion protection technology is required because lithium bromide is a corrosive liquid. I have a problem. In the case of an ammonia-water absorption type air conditioner, there is a problem of poisoning and fire due to leakage of ammonia, and thus it is difficult to adopt. Further, in the case of a freon-tetraethylene glycol dimethyl ether type absorption type air conditioner, there is a problem that the ozone layer is destroyed by freon.

[0004]

Therefore, in the present invention, a hydrofluorocarbon (hereinafter referred to as HFC) type refrigerant having no ozone layer depletion problem is used as a refrigerant, and compatibility with the HFC type refrigerant is used as an absorbing liquid. The problem is solved by using a high oil content such as fluorine oil, hindered ester oil, polyether oil and the like.

That is, the absorption type air conditioner of the invention of this application has a regenerator for evaporating the refrigerant by heating a thin absorbing solution in which the absorbing solution has absorbed the refrigerant and concentrating the absorbing solution, and the evaporated refrigerant. A condenser for liquefying the liquefied gas, an evaporator for evaporating the liquefied refrigerant to cool it, and an absorber for absorbing the evaporated refrigerant into the thick absorption solution sent from the regenerator. And in such an absorption type air conditioner, HFC which does not contain a chlorine atom in a molecule is used as the above-mentioned refrigerant.

Therefore, in the present invention, it is possible to avoid the problems inherent in the conventional lithium bromide, ammonia, or CFC. Specifically, the refrigerant is HF.
Since it is C, there is no problem of ozone layer depletion, the refrigerant is non-toxic and non-flammable, and the boiling point is 0.
Since it is below 0 ° C, it can be cooled to below 0 ° C, can be air-cooled, and has no corrosiveness. Therefore, the system can be easily assembled. In the present invention, it is preferable to use an oil having a high compatibility with the above HFC as the absorbing liquid.

Another invention of this application is that in the above-mentioned absorption type air conditioner, HFC is used as a refrigerant, and fluorine oil, hindered ester oil or polyether oil is used as an absorption liquid.
Alternatively, it is characterized by using a mixture thereof, and since these oils have good compatibility with HFC and the solution is stable, it is advantageous in increasing the coefficient of performance (COP). Further, the mixing of these oils is effective for adjusting the viscosity and specific gravity of the absorbing liquid.

In each of the above inventions, HFCs include tetrafluoroethane (HFC134a), difluoromethane (HFC32), pentafluoroethane (HFC1).
25) and difluoroethane (HFC152a), it is preferable to use one kind or a mixture of two or more kinds.

As the above-mentioned fluorine oil, one kind or a mixture of two or more kinds selected from the fluorine oil represented by the following general formula [1] and the fluorine oil represented by the following general formula [2] is preferable. Is.

[0010]

Embedded image In the formula [1], R1 to R4 are hydrogen atoms or fluorinated alkyl groups, and at least one of R1 to R4 is a fluorinated alkyl group. In formula [2], R1 to R6 are hydrogen atoms or a fluorinated alkyl group, and at least one of R1 to R6 is a fluorinated alkyl group.

The hindered ester oil may be one or two selected from hindered ester oils represented by the following general formula [3] and hindered ester oils represented by the general formula [4]. Suitably a mixture of more than one species.

[0012]

Embedded image In formulas [3] and [4], R7 to R11 are alkyl groups.

Still another invention of the present application is, in an absorption type air conditioner, selected from a fluorine oil represented by the following general formula [1] and a fluorine oil represented by the following general formula [2] as an absorbing liquid. The present invention is characterized by using one kind or a mixture of two or more kinds, and according to the present invention, a high coefficient of performance can be obtained by using HFC or the like as the refrigerant.

[0014]

[Chemical 6]

[0015]

According to the invention of this application, since HFC is used as the refrigerant in the absorption type air conditioner,
Adopting a direct expansion system that does not cause problems such as ozone layer depletion, toxicity, fire, and does not require advanced corrosion protection technology, facilitates air cooling, enables cooling to 0 ° C or less. This is possible, which is advantageous in terms of reduction of production cost and simplification of maintenance.

Further, as the absorbing liquid, the general formulas [1], [2]
A fluorine oil such as the above, a hindered ester oil or a polyether oil such as those represented by the general formulas [3] and [4], or a mixture thereof is used to obtain good compatibility with HFC. This is advantageous in increasing the coefficient of performance.

[0017]

BEST MODE FOR CARRYING OUT THE INVENTION

<Absorption type air conditioner system> The system is shown in FIG. 1 as an example of the air conditioner. In the figure, 1 is an outdoor unit,
Reference numeral 2 denotes an indoor unit, the outdoor unit 1 is composed of a regenerator 3, a condenser 4, and an absorber 5 as main elements, and the indoor unit 2 is composed of an evaporator 6 as main elements.

The regenerator 3 is supplied from the absorber 5 via the solution heat exchanger 10 and the solution pump 7 with a thin absorbing solution (a solution obtained by absorbing a refrigerant in the absorbing liquid). In the regenerator 3, a heating gas is supplied from the outside, and the refrigerant is evaporated by heating the thin absorbing solution with this gas, and the absorbing solution is concentrated (the refrigerant concentration becomes low).
Further, at the outlet of the regenerator 5, a rectifier 8 is provided in order to further separate the absorbing liquid from the refrigerant evaporated from the absorbing solution to increase the coefficient of performance.

The condenser 4 liquefies the evaporated refrigerant supplied from the regenerator 3 through the rectifier 8, and therefore the outdoor unit 1 is provided with an air cooling fan 9.

The refrigerant liquefied in the condenser 4 is supplied to the evaporator 6 of the indoor unit 2 through the expansion valve 11, and the evaporator 6 removes heat from the room to be vaporized. Therefore, the indoor unit 2 is provided with a fan 12.

The evaporator 5 of the outdoor unit 1 is supplied with the vaporized refrigerant from the evaporator 6, while the regenerator 3 is used.
To provide a concentrated concentrated absorption solution. Then, in this absorber 5, the vaporized refrigerant is absorbed by the thick absorbing solution, and the absorbing solution becomes thin (the refrigerant concentration becomes high). Heat exchanger 10 provided between the regenerator 3 and the absorber 5
Causes heat exchange between the high-temperature thick absorbing solution sent from the regenerator 3 and the low-temperature thin absorbing solution sent from the absorber 5, thereby lowering the temperature of the thick absorbing solution while reducing the temperature of the thin absorbing solution. The temperature is raised to improve the coefficient of performance.

<Preferable Combination Example 1 of Refrigerant-Absorbing Liquid>
In a preferred embodiment of the present invention, HFC is used as the refrigerant of the absorption type air conditioner and fluorine oil is used as the absorbing liquid.
(HFC / fluorine oil) system. That is, in this embodiment, the HFC is (HFC134a + HFC32 +
The following FPE oil (fluorinated pentaerythritol oil) is used as a fluorine oil by using a mixture of three kinds of HFC125).
And FDPE oil (fluorinated dipentaerythritol oil) are mixed at a weight ratio of 8: 2.

The above FPE oil contains the following compound of chemical formula 7 as a main component and contains a small amount of the compound of chemical formula 8.

[0024]

[Chemical 7]

[0025]

Embedded image

The FDPE oil contains the compound of the following chemical formula 9 as a main component and contains a small amount of the compound of the chemical formula 10.

[0027]

Embedded image

[0028]

Embedded image

Table 1 shows the viscosities and densities of the above FPE oil, FDPE oil and mixtures thereof.

[0030]

[Table 1]

FIG. 2 shows the operation cycle of the absorption type air conditioner on the concentration-temperature-pressure diagram of the (HFC / fluorine oil) system.

That is, in the figure, the isobar of the saturated pressure P1 of the refrigerant at the operating temperature of the evaporator 6 and the cooling temperature (absorber outlet temperature) line of the absorbing solution in the absorber 4 pass through the intersection A, etc. The concentration line is a thin absorption solution (fluorine oil concentration 90 wt%) that absorbs the refrigerant in the absorber 4 and is sent to the regenerator 3.
It is a concentration-temperature-pressure line of. Further, the isoconcentration line passing through the intersection C between the isobar of the saturation pressure Ph of the refrigerant at the operating temperature of the condenser 4 and the heating temperature (regenerator outlet temperature) of the absorbing solution in the regenerator 3 is the regenerator 3 3 is a concentration-temperature-pressure line of a concentrated absorption solution (fluorine oil concentration 95 wt%) that is concentrated in step S4 and sent to the absorber 4. When the intersection of the isobar Pl and the isoconcentration line Xh is B and the intersection of the isobar Ph and the isoconcentration line Xl is D, the operation cycle is A → B → C → D → A in the figure.

The operating temperature of the evaporator 6 is 5 ° C., the operating temperature of the condenser 4 is 50 ° C., and the temperature inside the absorber 4 is 45 ° C.
The temperature inside the regenerator 3 is 125 to 145 ° C.

The operation cycle will be specifically described as follows. A → B: Temperature rise due to heat exchange of the thin absorption solution absorbing the refrigerant by the absorber 4 with the high temperature concentrated absorption solution returning from the regenerator 3, and temperature rise until boiling due to heating in the regenerator 3. . B → C: Concentration of absorption solution in regenerator 3. C → D: Temperature drop due to heat exchange of the thick absorption solution separated from the refrigerant by the regenerator 3 with the low temperature thin absorption solution sent from the absorber 4, and temperature decrease due to external cooling in the absorber 4. D → A: Absorption of the refrigerant by the absorbing solution in the absorber 4.

As is apparent from FIG. 2, in the case of the system, the refrigerant pressure is higher than the atmospheric pressure, and the system can be easily assembled.

<Preferable Combination Example 2 of Refrigerant-Absorbing Liquid>
In another preferred embodiment of the present invention, HFC134a is used as the refrigerant of the absorption type air conditioner, and hindered ester oil (trade name RB68P) manufactured by Nippon Oil Co., Ltd. is used as the absorption liquid.
(HFC / hindered ester oil) system.

The operation cycle of the absorption type air conditioner is drawn on the concentration-temperature-pressure diagram of the (HFC / hindered ester oil) system as shown in FIG. A → B in the figure
→ C → D → A is the operation cycle.

The operating temperature of the evaporator 6 is 5 ° C., the operating temperature of the condenser 4 is 50 ° C., and the temperature inside the absorber 4 is 50 ° C.
˜70 ° C., the temperature inside the regenerator 3 is 110˜130 ° C. ing.

In this system, the temperature inside the absorber can be made higher than that in the previous example, which is advantageous for air cooling, and the temperature inside the regenerator can be made lower than that in the previous example, so that the refrigerant It is advantageous for preventing thermal deterioration.

[Brief description of drawings]

FIG. 1 is a system configuration diagram of an absorption type air conditioner.

[Fig. 2] Concentration of (HFC / fluorine oil) absorption type air conditioner-
Temperature-pressure diagram.

FIG. 3 is a concentration-temperature-pressure diagram of an (HFC / hindered ester oil) -based absorption type air conditioner.

[Explanation of symbols]

 1 Outdoor unit 2 Indoor unit 3 Regenerator 4 Condenser 5 Absorber 6 Evaporator 7 Solution pump 8 Fractionator 9 Air cooling fan 11 Expansion valve 12 Fan

 ─────────────────────────────────────────────────── ─── Continuation of front page (72) Inventor Shiro Yakushiji 1304 Kanaoka-machi, Sakai City, Osaka Prefecture Daikin Industries, Ltd. Kanaoka Factory, Sakai Factory (72) Naoaki Izumiya 1304, Kanaoka-machi, Sakai City, Osaka Daikin Industries, Ltd. Sakai Plant Kanaoka Factory

Claims (9)

[Claims] 1. A regenerator for evaporating the refrigerant by heating a thin absorbing solution in which the refrigerant is absorbed by the absorbing liquid to concentrate the absorbing solution, a condenser for liquefying the evaporated refrigerant, and a liquefied refrigerant. In an absorption type air conditioner equipped with an evaporator that vaporizes and cools, and an absorber that absorbs the vaporized refrigerant into a concentrated absorbing solution sent from the regenerator, hydrofluorocarbon is used as the refrigerant. Absorption type air conditioner. 2. The absorption type air conditioner according to claim 1, wherein fluorine oil is used as the absorbing liquid. 3. The absorption type air conditioner according to claim 1, wherein a hindered ester oil is used as the absorption liquid. 4. The absorption type air conditioner according to claim 1, wherein a polyether oil is used as the absorbing liquid. 5. The absorption type air conditioner according to claim 1, wherein a mixture of fluorine oil, hindered ester oil and polyether oil is used as the absorbing liquid. 6. The absorption type air conditioner according to any one of claims 1 to 5, wherein the refrigerant is selected from tetrafluoroethane, difluoromethane, pentafluoroethane and difluoroethane. An absorption type air conditioner, which is a kind or a mixture of two or more kinds. 7. The absorption type air conditioner according to claim 2, wherein the absorbing liquid is selected from among the fluorine oil represented by the following general formula [1] and the fluorine oil represented by the following general formula [2]. An absorption type air conditioner, which is a selected one kind or a mixture of two or more kinds. Embedded image (In the formula [1], R1 to R4 are hydrogen atoms or a fluorinated alkyl group, and at least one of R1 to R4 is a fluorinated alkyl group. In the formula [2], R1 to R6 are hydrogen. An atom or a fluorinated alkyl group, and at least one of R1 to R6 is a fluorinated alkyl group.) 8. The absorption type air conditioner according to claim 3, wherein the absorbing liquid is a hindered ester oil represented by the following general formula [3] and a hindered ester represented by the general formula [4]. An absorption type air conditioner, which is one kind or a mixture of two or more kinds selected from oils. Embedded image (In the formulas [3] and [4], R7 to R11 are alkyl groups.) 9. A regenerator that evaporates the refrigerant by heating a thin absorbent solution in which the refrigerant has been absorbed by the absorbing liquid to concentrate the absorbing solution, a condenser that liquefies the evaporated refrigerant, and a liquefied refrigerant. In an absorption type air conditioner equipped with an evaporator that vaporizes and cools, and an absorber that absorbs the vaporized refrigerant into a concentrated absorbing solution sent from the regenerator, the absorption liquid is represented by the following general formula [1]. An absorption type air conditioner characterized by using one kind or a mixture of two or more kinds selected from the fluorine oil represented and the fluorine oil represented by the general formula [2]. Embedded image (In the formula [1], R1 to R4 are hydrogen atoms or a fluorinated alkyl group, and at least one of R1 to R4 is a fluorinated alkyl group. In the formula [2], R1 to R6 are hydrogen. An atom or a fluorinated alkyl group, and at least one of R1 to R6 is a fluorinated alkyl group.)