JP2000009362A - Hybrid compression/absorption heat pump - Google Patents

Abstract

PROBLEM TO BE SOLVED: To obtain a hybrid heat pump for feeding an air conditioning heat exchanger with both refrigerant gas compressed through a compressor and refrigerant gas generated from a generator in which circulation of solution can be reduced by extracting a part of refrigerant compressed through a compressor under intermediate pressure and causing an absorber to absorb it. SOLUTION: At the time of cooling, high temperature high pressure refrigerant gas compressed through a compressor 2 is fed through a refrigerant line 5 to an outdoor heat exchanger 3 and condensed refrigerant gas is fed to an indoor heat exchanger 4 where cooling is performed with vaporization latent heat before the refrigerant gas is sucked back to the compressor 2. A suction refrigerant supply line 11 is connected across one delivery part of the compressor 2 and the inlet of an absorber 6 and a part of refrigerant is extracted at an intermediate pressure stage in the way of compression through the compressor 2 and fed to the absorber 6. The refrigerant introduced to the absorber 6 is absorbed by an absorbent and mixture solution of the absorbent and refrigerant is fed by means of a pump 12 from a solution supply line 13 to a generator 7 through a regenerator 8.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a hybrid heat pump apparatus in which a compression cycle and an absorption cycle are combined.

[0002]

2. Description of the Related Art The inventors of the present invention have previously disclosed a hybrid heat pump apparatus in which a heat pump apparatus equipped with a compressor is combined with an absorption cycle, so that part of the work of the compressor is replaced by the absorption cycle. And filed an application as Japanese Patent Application No. 10-149693.

That is, as shown in FIG. 7, a part of the refrigerant sucked into the compressor (31) is absorbed into the absorbent by the absorber (32) in the absorption cycle, and the mixture of the absorbent and the refrigerant is pumped.
(33) and the engine (3
After extracting as high-pressure gas by the generator (36) using heat of the cooling water circuit and / or the exhaust gas passage (4) of (4) as a heat source, the refrigerant is discharged from the compressor (31) on the discharge side. Line (3
It is combined with 7) and sent to the air-conditioning heat exchangers (38) and (39).

[0004] In this way, by taking part of the work of the compressor (31) into the absorption cycle, the load on the compressor (31) is reduced, and the fuel consumption of the engine (34) can be reduced, while
By utilizing the waste heat of the compressor engine (34) as the heat source of the generator (36), a special energy source such as a burner is not required, and the energy consumption of the entire refrigeration cycle can be reduced.

[0005]

Generally, refrigerant number R22, which is exactly Freon, is widely used as a refrigerant in a compression cycle, and recently R407C, R134a, etc. have been used as alternative refrigerants which do not destroy the ozone layer. ing. These components are suitable as refrigerants used in the compression cycle, and pose no problem when used only in the compression cycle.

However, since the refrigerant used in these compression cycles has a large molecular weight of R22 of 83, the refrigerant has low absorbency to the absorbent, and the refrigerant concentration of the high-concentration solution in the state of being absorbed in the absorbent is low. There is a limit. On the other hand, in the hybrid type, waste heat such as engine cooling water or exhaust gas is used as a heat source of the generator, but if the temperature of the generator is too high, the refrigerant itself will undergo thermal decomposition,
The generator cannot be operated at an endlessly high temperature,
There is also a lower limit to the refrigerant concentration of the low concentration side solution after the generation of the refrigerant gas, the difference in concentration between the high concentration side and the low concentration side is small, and the solution circulation ratio, which is the flow ratio between the solution and the refrigerant, is large. There is.

FIG. 8 is a During diagram showing the relationship between the refrigerant pressure and the temperature in the refrigeration cycle shown in FIG. 7, wherein the broken line with the arrow on the left side indicates the compressor cycle and the arrow on the right side. Indicates the absorption cycle, and the mixture of the absorbent and the refrigerant sucked out of the absorber at point a at the left end corner of the absorption cycle gradually increases in pressure and temperature when being sent to the generator. Then, at point b in the middle, the pressure and the temperature are further increased by heat exchange with the regenerator and introduced into the generator. At that time, the refrigerant concentration on the high concentration side is ξ1 = 0.30, The refrigerant concentration after releasing the refrigerant in the generator is ξ2 = 0.15, the difference is only 0.15, and the solution circulation ratio is 1 / (0.30−
0.15) = 6-7. Here, the solution circulation ratio is a factor determined by 1 / (refrigerant concentration of high concentration solution−refrigerant concentration of cold concentration solution).

For this reason, in order to absorb as much refrigerant as can effectively reduce the load on the compressor, a large amount of absorbent must be circulated, and the entire apparatus constituting the absorption cycle becomes large, In addition, there is a problem that the energy consumption of the pump for circulating the absorbent increases.

Further, the CFC refrigerant for the compression cycle has a problem that the amount of latent heat of vaporization (liquefaction) per mass is lower than that of water or ammonia used in the absorption cycle. This is not a problem in the compression cycle where the amount of latent heat per volume is important, but the effect is reduced by half in the absorption cycle, which also increases the amount of solution circulation to absorb a large amount of refrigerant. Therefore, there are drawbacks such as an increase in the size of the entire apparatus.

The present invention makes it possible to reduce the amount of the solution circulating in the absorption cycle in the hybrid heat pump in which the compression cycle and the absorption cycle are combined as described above, thereby increasing the size of the entire apparatus. It is an object of the present invention to provide a heat pump device free from heat.

[0011]

SUMMARY OF THE INVENTION In order to solve the above-mentioned problems, the invention of claim 1 of the present application relates to a refrigerant gas compressed by a compressor of a compression cycle and a refrigerant gas generated by a generator of an absorption cycle. Is a hybrid heat pump device that sends both to the air-conditioning heat exchanger, in which a part of the refrigerant compressed by the compressor is extracted at an intermediate pressure state, and the extracted refrigerant is absorbed by the absorber of the absorption cycle. What is to be absorbed is provided.

A second aspect of the present invention is a hybrid heat pump apparatus for sending both a refrigerant gas compressed by a compressor of a compression cycle and a refrigerant gas generated by a generator of an absorption cycle to a heat exchanger for air conditioning. Thus, there is provided an apparatus wherein a refrigerant gas is separated from a mixture of an absorbent and an ungasified refrigerant returning from a generator to an absorber, and the separated refrigerant gas is sucked into a compressor.

Further, in order to achieve the same object, the invention according to claim 3 of the present application is directed to a method in which refrigerant gas compressed by a compressor of a compression cycle and refrigerant gas generated by a generator of an absorption cycle are both heated for air conditioning. A hybrid type heat pump device to send out to the exchanger, the refrigerant sent out to the air conditioning heat exchanger consists of a mixture of refrigerant A and refrigerant B, separate these refrigerants A and B, and either one It is to be sucked into a compressor and the other is absorbed into an absorber.

[0014]

DESCRIPTION OF THE PREFERRED EMBODIMENTS FIG. 1 is a refrigerant circuit diagram of a heat pump device showing one embodiment implemented according to the invention of claim 1 of the present application.

In the figure, (1) indicates an engine, (2) indicates a compressor driven by the engine (1), (3) indicates an outdoor heat exchanger, and (4) indicates an indoor heat exchanger. . The high-temperature and high-pressure refrigerant gas compressed by the compressor (2)
The refrigerant is first sent to the outdoor heat exchanger (3) through the refrigerant line (5), and condensed in the outdoor heat exchanger (3), and then the indoor heat exchanger
The air is sent to (4), cooled by the latent heat of vaporization, and then sucked into the compressor (2) again. This is a compression cycle.

This circuit shows a state only at the time of cooling. Actually, the circuit is switched to circulate the refrigerant from the indoor heat exchanger (4) to the outdoor heat exchanger (3) at the time of heating. Although a four-way valve and other devices are provided, only the minimum devices necessary for cooling are shown here.

(6) an absorber constituting an absorption cycle;
(7) is a generator, and (8) is a regenerator. (9) is an engine cooling water circuit circulated by a cooling water pump (10), wherein the generator (8) is disposed in the cooling water circuit (9), and the cooling water circuit (9) The heat of the cooling water inside is used as a heat source of the generator (7).

(11) is an absorption refrigerant supply line for supplying refrigerant to the absorber (6), which is a compressor (2)
Is connected across the one discharge part and the inlet of the absorber (6). According to the present invention, a part of the refrigerant at the intermediate pressure stage in the middle of being compressed by the compressor (2) is extracted and absorbed. To the vessel (6).

The refrigerant introduced into the absorber (6) is absorbed by the absorbent, and a mixed solution of the absorbent and the refrigerant becomes
A regenerator from the solution supply line (13) by the pump (12)
It is supplied to the generator (7) through (8). In the generator (7), only the refrigerant is separated from the absorbent into a high-pressure gas by being heated by the heat of the cooling water circuit (9), and is sent from the compressor (2) from the delivery line (14). The refrigerant merges with the discharged refrigerant in the refrigerant line (5) and flows toward the outdoor heat exchanger (3). On the other hand, the absorbent in the generator (7) returns from the return line (15) through the regenerator (8) to the absorber (6), as in a general absorption cycle. In the drawings, (16) and (17) are expansion valves arranged in the lines shown in the drawings.

FIG. 2 is a During diagram in the case of the embodiment of FIG. 1. In this way, by bleeding and supplying the gas to the absorber (6) in the absorption cycle in the middle of the compression stroke,
The refrigerant is supplied to the absorber (6) at a somewhat high pressure, and the amount of absorption into the absorbent increases accordingly, that is, the concentration of the high concentration side solution becomes ξ1 = 0.40, which is higher than before. On the other hand, the low concentration side solution concentration of the generator (7) is 0.1
If it is 5, the solution circulation ratio is reduced accordingly, and the efficiency of the absorption cycle can be improved.

FIG. 3 shows one embodiment implemented according to the invention of claim 2 of this application. In this embodiment, as in FIG. 7, a part of the refrigerant is absorbed by a branch line (22) that branches off in the middle of a line (21) returning from the indoor heat exchanger (4) to the compressor (2) during cooling. It is made to inhale into the vessel (6). Then, pump (1) from absorber (6)
The mixture of the refrigerant and the absorbent sucked out in 2) is
The high-temperature and high-pressure refrigerant gas supplied to the first generator (7) through the two regenerators (8) and (23) and separated from the absorbent is supplied from the discharge line (14) to the refrigerant line ( Merge into 5).

Further, in the absorbent leaving the first generator (7), the ungasified refrigerant remaining without being separated is mixed, and this is transferred to the second generator (22). Supply. In the second generator (22), as in the case of the first generator (7), it is heated by the heat of the engine cooling water circuit (9) to generate a slightly high-pressure gasified refrigerant. This gasified refrigerant is
Since the temperature and the pressure are not high enough to join the refrigerant line (5), the refrigerant gas is injected into the intermediate pressure stage in the middle of the compression process in the compressor (2). Higher temperature together with the refrigerant gas from
After being compressed to a high pressure, it is sent to the refrigerant line (5). A line (24) leading from the first generator (7) to the second generator (22) passes through a second regenerator (23) on the way, and furthermore a second generator (22). An expansion valve (25) is provided in front of this to temporarily reduce the pressure.

FIG. 4 is a During diagram in the case of the second embodiment, in which the pressure drops when moving from the first generator (7) to the second generator (22). However, the concentration of the low-concentration side solution at the point c after the separation in the second generator at (22) decreases to ξ = 0.10. Therefore, FIG.
Unlike the above case, the concentration of the high-concentration solution is not different from the normal case, but the concentration of the low-concentration solution decreases, so that the solution circulation ratio increases and the efficiency of the absorption cycle can be similarly improved. .

FIG. 5 is an example of an embodiment implemented according to the invention of claim 3 of the present application. The total amount of the mixed refrigerant obtained by mixing two or more refrigerants is supplied from the outdoor heat exchanger (3) and the indoor heat exchanger (4) to the absorber (6) through the line (21).
Led to. The mixed refrigerant has good compatibility with the refrigerant A composed of one or a plurality of substances such as HCFCs, HFCs, and the like generally used for the compression cycle, that is, has good absorbency with the absorbent, and A mixture with a refrigerant B composed of one or more substances having a large latent heat of vaporization,
In the absorber (6), the refrigerant B having good absorbency is separated from the refrigerant A by being absorbed by the absorbent. That is, the absorber
In (6), both the normal absorption operation and the refrigerant separation operation are performed.

The mixed liquid of the absorbent and the refrigerant B is supplied to the regenerator (8)
Is sent to the generator (7), and the high-temperature and high-pressure refrigerant gas is combined with the refrigerant line (5) and supplied to the outdoor heat exchanger (3). On the other hand, the refrigerant A not absorbed by the absorbent is sucked into the compressor (2) from another suction line (26), is compressed to a high temperature and a high pressure, and is then discharged to the refrigerant line (5). Become.

The substance having a good absorbency by the absorbent and having a large latent heat of vaporization depends on the absorbent. For example, in addition to TFE (tetrafluoroethanol), ammonia, which is widely used in an absorption cycle, For example, propanol pentafluoride (5FP) may be used. On the other hand, as the absorbent, DMA, E1
81, PAG and the like.

FIG. 6 is a During diagram in the case of this embodiment, and it is possible to increase the high-concentration-side solution concentration by using a substance having excellent absorbability as a refrigerant for the absorption cycle. Thus, the efficiency of the absorption cycle can be improved.

[0028]

According to the first aspect of the present invention, since the intermediate-pressure refrigerant extracted from the compressor is supplied to the absorber of the absorption cycle, the absorption rate is lower than when the low-pressure refrigerant is supplied. Increases, the solution circulation ratio decreases with an increase in the solution concentration on the high concentration side, and it is not necessary to increase the size of the device constituting the absorption cycle and increase the solution circulation amount in the hybrid type. This has the effect. Moreover, no special pressurizing device is required because the compressor of the compression cycle is also used as a pressurizer.

According to the invention of claim 2 of the present application, the ungasified refrigerant in the absorbent returning from the generator is separated again and sucked into the compressor, so that the low concentration side solution As the concentration decreases, the solution circulation ratio decreases. Similarly, in the hybrid type, there is the effect that it is not necessary to increase the size of the absorption cycle device and increase the solution circulation amount.

Further, according to the invention of claim 3 of the present application, one of the separated mixed refrigerant is sucked into the compressor and the other is absorbed by the absorber, so that the refrigerant is absorbed by the absorber. By using a refrigerant having excellent absorption by the absorbent as the refrigerant to be used, the concentration of the high concentration side solution in the absorption cycle can be increased, and as a result, the solution circulation ratio can be reduced. There is an effect that it is not necessary to increase the size and increase the solution circulation amount.

[Brief description of the drawings]

FIG. 1 is a refrigerant circuit diagram of a heat pump device showing an embodiment of the present invention.

FIG. 2 is a During diagram showing a relationship between refrigerant pressure and temperature in the embodiment of FIG.

FIG. 3 is a refrigerant circuit diagram of a heat pump device showing another embodiment of the present invention.

FIG. 4 is a During diagram showing a relationship between a refrigerant pressure and a temperature in the embodiment of FIG. 3;

FIG. 5 is a refrigerant circuit diagram of a heat pump device showing still another embodiment of the present invention.

FIG. 6 is a During diagram showing a relationship between refrigerant pressure and temperature in the embodiment of FIG.

FIG. 7 is a refrigerant circuit diagram showing an example of a hybrid heat pump device.

FIG. 8 is a During diagram.

[Explanation of symbols]

 (2) Compressor (3) Outdoor heat exchanger (4) Indoor heat exchanger (6) Absorber (7) Generator (23) Generator

Claims (3)

[Claims] 1. A hybrid heat pump device for sending a refrigerant gas compressed by a compressor of a compression cycle and a refrigerant gas generated by a generator of an absorption cycle to a heat exchanger for air conditioning. A compression / absorption hybrid heat pump device in which a part of the refrigerant to be extracted is bled at an intermediate pressure state so that the bled refrigerant is absorbed by an absorber of an absorption cycle. 2. A hybrid heat pump device for sending both a refrigerant gas compressed by a compressor of a compression cycle and a refrigerant gas generated by a generator of an absorption cycle to a heat exchanger for air conditioning. A compression / absorption hybrid heat pump device wherein a refrigerant gas is separated from a mixture of an absorbent and an ungasified refrigerant returning to a compressor, and the separated refrigerant gas is sucked into a compressor. 3. A hybrid heat pump device for sending both a refrigerant gas compressed by a compressor of a compression cycle and a refrigerant gas generated by a generator of an absorption cycle to a heat exchanger for air conditioning, comprising: The refrigerant sent to the device is composed of a mixture of the refrigerant A and the refrigerant B. The refrigerant A and the refrigerant B are separated, and one of them is sucked into the compressor and the other is absorbed in the absorber. Compression and absorption hybrid heat pump device.