JPH06137703A - Tripple effect heat pump - Google Patents

Abstract

PURPOSE:To improve thermal efficiency by raising by means of a mechanical compressor the pressure of vapor generated by a third evaporator, and condensing the vapor by use of a third absorber, the second evaporator being connected with at least one of a third condenser and a third absorber by means of a second heating medium circulating passage so as to provide a second evaporator with heat source. CONSTITUTION:Vapor of a third generator 11 driven by heat from a second condenser 2 and a second absorber 4 is fed to a third condenser 12 through a feed passage 29, then the condensate is made to flow into a third evaporator 13 through feed passage 30. The third evaporator 13 is provided with heat absorber, and carries out vapor evaporation. The evaporated vapor is compressed by a mechanical compressor 31 and is fed to the third absorber 14 through a feed passage 32. The operation pressure in the third absorber 14 increases and the temperature in the third generator 11 decreases: thus, a third effect heat pump can be driven, realizing an operation of high thermal efficiency.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a heat pump, and more particularly to a triple effect absorption heat pump combining three absorption heat pump systems for the first effect, the second effect and the third effect. A heat pump equipped with a machine.

[0002]

2. Description of the Related Art With regard to this type of absorption heat pump, not only improvement of its equipment but also improvement of its system is remarkable. A typical example thereof is a double-effect heat pump.

The most efficient way of operating this double-effect heat pump system is to transfer the heat of the first condenser and the heat of the first absorber to the first generator. With such a configuration, by taking heat from the second condenser and the second absorber, it is possible to take out the heat quantity 4Q that is four times the heat quantity Q given to the first generator.

In order to establish this relationship, when the same effector is used for the first effect and the second effect, the temperatures of the first evaporator and the second evaporator are substantially the same. Requires increasing the temperature of the first generator and increasing the temperatures of the first condenser and the first absorber.

[0005]

However, in the case where the refrigerant and the absorbent are water-lithium bromide type, it is established by increasing the temperature and concentration of the first generator, but the temperature in this case is 180 It becomes more than ℃ and corrosion progresses and it cannot be put to practical use.

In the case of a water-ammonia system, it is necessary to operate under conditions of high temperature and low ammonia concentration, a high pressure vessel is required, and equipment costs increase, and
For stable operation, a reflux operation is required in the first generator in order to keep the generated vapor concentration constant. As a result, the thermal efficiency decreases.

In order to solve this problem, the first effect is a lithium bromide system and the second effect is a water-ammonia system, and the temperature of the second generator is lowered to achieve a double effect and to easily accept low temperature energy. Therefore, there is a method of providing a mechanical compressor between the second evaporator and the second absorber.

However, even in this method, the temperature of the first effect is high, and the general two-working fluid of water and inorganic salt causes severe corrosion, and it is impossible to assemble the double effect or more.

Therefore, an object of the present invention is to solve the above-mentioned restrictions on the apparatus and to construct a heat pump system having high thermal efficiency.

[0010]

Means for Solving the Problems The above problems are solved by forming a first absorption heat pump by a first generator and a first condenser using a refrigerant and an absorbent, respectively, and by using a second generator and a second condenser. , A second evaporator and a third absorber constitute a second absorption heat pump, and a third generator, a third condenser, a third evaporator,
A third absorption heat pump is constituted by the third absorber, the vapor generated in the first generator is passed through the first condenser in the second generator, and the condensate is guided to the second evaporator.
The vapor generated in the second generator is passed through the second condenser in the third generator, the condensate is guided to the second evaporator, the external driving heat source is used as the driving heat source of the first generator, and the second absorber is used. And a third generator, which constitutes a first heat medium circulation path, is heated by the second absorber, and heat of the heat medium passing through the first heat medium circulation path is generated by the second generator. Then, the heat of the vapor transferred to the heater of the third generator is used as a driving heat source of the third generator, and the heat is provided between at least one of the third condenser and the third absorber and the second evaporator. Is connected by the second heat medium circuit,
The problem can be solved by using the heating source of the second evaporator, and the vapor generated in the third evaporator is pressurized by a mechanical compressor to be condensed in the third absorber.

In this case, in the second heat medium circulation passage, the heat medium passes through both the third absorber and the third condenser in this order, and then the second heat medium.
It can be configured to reach an evaporator.

On the other hand, a first absorption heat pump is constituted by a first generator and a first condenser using a refrigerant and an absorbent, respectively, and a second generator, a second condenser, a second evaporator, and a third evaporator. The absorber constitutes a second absorption heat pump, the third generator, the third condenser, the third evaporator and the third absorber constitute a third absorption heat pump, and the vapor generated in the first generator. Through the first condenser in the second generator, the condensate is guided to the second evaporator, the vapor generated in the second generator is passed through the second condenser in the third generator, and the condensate To a second evaporator, an external drive heat source is used as a drive heat source for the first generator, and a first heat medium circulation path that circulates between the second absorber and the third generator is configured, and the second absorption First heated with a vessel
The heat of the heat medium passing through the heat medium circulation path and the heat of the vapor generated in the second generator and transferred to the heater of the third generator are used as the driving heat source of the third generator, and the third evaporation is performed. The evaporator and the second evaporator are connected by a third heat medium circulation path to serve as a heating source for the second evaporator, and the vapor generated in the third evaporator is pressurized by a mechanical compressor to be absorbed by the third absorber. It may be configured to condense in a container.

In this case, it is possible to connect the third absorber and the third condenser by the fourth heat medium circulation path.

Further, using a refrigerant and an absorbent, respectively,
A first absorption heat pump is configured by the first generator and the first condenser, and the second generator, the second condenser, the second evaporator, and the third
The absorber constitutes the second absorption heat pump, and the third generator, the third condenser, the third evaporator, and the third absorber make the third heat pump.
While constituting an absorption heat pump, the vapor generated in the first generator is passed through the first condenser in the second generator,
The condensate is guided to the second evaporator, the vapor generated in the second generator is passed through the second condenser in the third generator, the condensate is guided to the second evaporator, and the external drive heat source is set to the first. As a heat source for driving the generator, a first heat medium circulation path that circulates between the second absorber and the third generator is configured, and heat that is heated by the second absorber and passes through the first heat medium circulation path. The heat of the medium and the heat of the vapor generated by the second generator and transferred to the heater of the third generator are used as the driving heat source of the third generator, and the third absorber and the third condenser are used. Are connected by a fourth heat medium circulation path, the heat source of the second evaporator receives heat through the fifth heat conducting path, and the heat source of the third evaporator receives heat through the sixth heat conducting path. The heat conducting path and the sixth heat conducting path are independent of the fourth heat medium circulating path, and the vapor generated in the third evaporator is pressurized by a mechanical compressor. It may be configured to achieve condensation in the third absorber.

In each of the above examples, the refrigerant and the absorbent in the first effect and the second effect are water-lithium bromide or TFE (tetrafluoroethanol) -E181 (tetraethylene glycol dimethyl ether) having no gas-liquid equilibrium. The refrigerant and the absorbent in the second effect are water-ammonia or R134, in which the refrigerant has compressibility.
a-E181.

[0016]

In the first aspect of the present invention, the generator and condenser for the first effect, the absorption heat pump for the second effect, and the absorption heat pump for the third effect are combined, and the third condenser and the third condenser are combined. Since the heat of the absorber is used to heat the second evaporator, the operating temperature of the second absorber can be increased. Further, since the vapor generated in the third evaporator is compressed and pressurized by the mechanical compressor and guided to the third absorber, the operating pressure of the third absorber can be increased,
Correspondingly, the operating temperature of the third generator can be lowered, so that heat can be easily transferred from the second absorber having a high operating temperature to the third generator having a low operating temperature.

On the other hand, even when the operating temperature of the third generator is -40 ° C. (in the case of water-ammonia system), the compression ratio by the mechanical compressor is selected so that the condenser can be operated like a normal refrigerator. Since the refrigeration system can be constructed by increasing the pressure to the intermediate pressure of the absorber without pressurizing to the pressure of, the power consumption of the mechanical compressor according to the present invention is the mechanical power of the refrigerator used in the conventional refrigeration system. Compared to the power consumption of the compressor,
It becomes about 1/2 to 1/3. Moreover, by using the mechanical compressor, the pressure of the third evaporator can be freely adjusted, and therefore the temperature of the third evaporator can also be freely adjusted within the range of -40 ° C to 0 ° C.

As another advantage of using the mechanical compressor in the present invention, in the second aspect of the present invention, as described above, the operating temperature of the third generator can be lowered, so that the medium temperature water (50 (About -60 ° C.) is supplied to the third generator, the evaporation operation is performed in the second evaporator, and the cold water is efficiently produced in the third circulation path between the second evaporator and the third evaporator. By the way, the coefficient of performance for obtaining cold water of 0 ° C to 10 ° C is 2.1 to 2.6, which is extremely high.

[0019]

The present invention will be described in more detail by way of examples with reference to the drawings. FIG. 1 shows the first mode,
Using the refrigerant and the absorbent respectively, the first generator 01, the first generator 01
The condenser 02 constitutes the first absorption heat pump and the second absorption heat pump.
Generator 1, second condenser 2, second evaporator 3, second absorber 4
The second absorption heat pump is constituted by the third generator 1
1, third condenser 12, third evaporator 13, third absorber 14
This constitutes a third absorption heat pump. Here, for example, a water-lithium bromide system can be used in the first effect and the second effect, and a water-ammonia system can be used in the third effect.

A suitable external driving heat source 20 is externally applied to the first generator 01, and the vapor generated in the first generator 01 is supplied to the first condenser in the second generator 1 through the supply line 21A. After passing through 02, the condensate is configured to be guided to the second evaporator 3. Further, after passing the vapor generated in the heated second generator 1 through the second conduit 2 in the third generator 11 through the supply pipeline 21B, the condensate is also guided to the second evaporator 3. Is configured.

Further, a first heat medium circulation path 23 circulated by a pump 22 is formed between the second absorber 4 and the third generator 11, and is heated by the second absorber 4 to circulate the first heat medium. The heat medium passing through the passage 23 and the heat of the vapor generated in the second generator 1 are used as the driving heat source for the third generator 11.

The vapor from the second generator 1 to the third generator 11 is condensed in the second condenser 2 and gives heat to the third effect system, and the condensed liquid condensed here is the second evaporator. Three
And is vaporized by a heat medium (heated water in this case) passing through a second heat medium circulation passage 24, which will be described later, and the evaporative vapor is led to the second absorber 4 via a pipe passage 50.

Between the second absorber 4 and the first generator 01, supply lines 26A, 26B for the concentrated liquid due to the concentration in the first generator 01 and the second generator 1 by the circulation pump 25.
And the first by the return line 27 of the diluted liquid accompanying absorption and condensation
An exchange line is constructed. In this circulation exchange process, heat exchange between the concentrated liquid and the diluted liquid is performed by the first heat exchanger 28A,
28B. Therefore,
The vapor introduced into the second absorber 4 via the pipe 50 comes into contact with the concentrated liquid from the second generator 1 to be absorbed and condensed, and the heat of condensation at this time is used as a heating heat source for the third generator 11. It

The same applies to the third effect heat pump which is in charge of the low temperature side, and the second condenser 2 and the second absorber 4 are provided.
The evaporated refrigerant (in this case, ammonia vapor) in the third generator 11, which is driven by receiving the heat from, is supplied to the third condenser 12 by the supply pipeline 50, and the condensate there is supplied by the supply pipeline 30. It is led to the third evaporator 13. In the third evaporator 13, the heat absorption source 38 is supplied and the ammonia vapor is evaporated. Evaporated ammonia vapor is third
A mechanical compressor 31 compresses and pressurizes the absorber 14 and supplies the absorber 14 through a supply pipe 32.

Between the third absorber 14 and the third generator 11, a concentrated liquid supply conduit 34 by a circulation pump 33 and a second exchange conduit by a diluted liquid return conduit 35 are formed.
In this circulation process, heat exchange between the concentrated liquid and the diluted liquid is performed by the second heat exchanger 36.

On the other hand, the third absorber 14, the third condenser 12,
A second heat medium circulation path 24 connected in this order to the second evaporator 3 is formed. 37 is a pump for the circulation. In the second heat medium circulation path 24, the third absorber 1
Cooling pipe 14a at 4 and cooling pipe 1 at the third condenser 12
Heat is taken by the portion 2a, and this heat is given to the second evaporator 3 for the second effect. If there is a surplus, the heat exchanger 39
It is designed to be taken out as warm water 40 or the like.

In the case of the first mode, when heat is applied to the second evaporator 3, it can be applied from either the third absorber 14 or the third condenser 12.

In such a system, by appropriately selecting the temperature and pressure in the third evaporator 13 in the third effect of the water-ammonia system, the evaporation temperature there is -40 ° C to 0 ° C. Low temperatures in the range can be obtained.

By the way, conventionally, in the water-lithium bromide-based absorption refrigerator, it is not possible to obtain a low temperature of 0 ° C. or lower, and in the water-ammonia system, there is a vapor-liquid equilibrium, so that the reflux operation is performed as described above. It was necessary and had poor thermal efficiency.

However, in constructing the third effect heat pump, since the refrigerant (ammonia) is compressed and boosted by the mechanical compressor 31, the third absorber 14 is used.
The operating pressure on the 3rd generator 11 correspondingly increases.
Temperature drops. Therefore, the third effect heat pump can be driven without the need for the reflux operation in the third generator, and the operation with high thermal efficiency can be performed. Then, the heat absorption source 38 that has passed through the heat transfer tube 13a of the third evaporator 13 is finally the low temperature heat source 3 in the range of -40 ° C to 0 ° C.
8a.

The above-mentioned mechanical compressor 31 can be driven by an internal combustion engine such as a gas engine, a gas turbine or a diesel engine. In this case, the heat of the exhaust gas is transmitted to the first generator 01. By throwing in, operating efficiency (coefficient of performance) can be further improved.

In the present invention, the low temperature heat source 38a described above is used.
To obtain the low temperature heat source 38a as cold water and obtain the hot water 40 of, for example, about 50 ° C. from the heat exchanger 39 to obtain a heat pump for freezing or for producing hot / cold water. it can. When the mechanical compressor 31 is driven by the above-mentioned internal combustion engine, a highly efficient cogeneration system can be constructed.

Conventionally, for example, when the outside air temperature becomes about -5 to -20 ° C in a cold region, it is impossible to drive the absorption refrigerator using this heat, but the present invention According to the above, this is possible, and driving can be performed with a coefficient of performance of 2 or more.

In the present invention, for example, the coefficient of performance for obtaining hot water at 50 ° C. is 2.3, and the coefficient of performance for producing cold water at −20 ° C. is 1.3. Therefore, it is found that the coefficient of performance is higher than that of the conventional absorption refrigerator.

On the other hand, conventionally, in a factory or the like, 60 ° C.
Despite the enormous amount of so-called medium-temperature water, its use is limited, and in most cases it is abandoned. Therefore, as shown in FIG.
The heat of the medium temperature water 41 at an intermediate temperature between the external drive heat source 20 and the heat absorbing source (heat absorbing source passing through the third heat medium circulation path) is transferred to the condenser 4
By giving it via 2, the refrigerating capacity in the absorption heat pump of the third effect can be further enhanced.

In the second embodiment shown in FIG. 2, the fourth embodiment
In the heat medium circulation path 45, the heat medium circulated by the circulation pump 37 takes away heat from the cooling pipe 14a in the third absorber 14 and the cooling pipe 12a in the third condenser 12, and condenses this heat into hot water. The water is supplied as warm water 44 from the container 43 to radiate heat to the outside. Further, in the third heat medium circulation path 46, the heat medium circulated by the circulation pump 47 passes through the cooling pipe 13 a in the third evaporator 13 and the second evaporator 3, and the cold water 49 is taken out by the heat exchanger 48. Is done.

FIG. 3 shows a third mode, in which a fourth heat medium circulation passage 45 is provided between the third absorber 14 and the third condenser 12.
And the fifth heat conducting path 6 when heating the second evaporator.
For example, the low-temperature heat medium 61 is made to enter through 1 and the heat source 61 of the third evaporator 13 is made to pass through the heat exchanger 48 provided in the sixth heat input conducting path 62. Therefore,
The fifth heat input passage 60 and the sixth heat passage 62 are independent of the fourth heat medium circulation passage 45.

(Examples) Next, examples will be shown to clarify the effects of the present invention. This Example 1 had the structure shown in FIG. 1, and TFE-E181 was used in the first effect and the second effect, and water-ammonia was used in the third effect, as the refrigerant and the absorbent. As the driving heat source 20 from the outside, steam having a pressure (16 kgf / cm ² abs) is used, and the concentration, temperature and pressure in each device are as shown in Table 1.

On the other hand, as the intermediate compressor 31, a 250 KW screw type ammonia compressor (compression ratio 2.2) was used.
The flow rate of ammonia at this time was 8050 to 8100 kg / hr.
As a result, in the heat exchanger 39, warm water having an inlet temperature of 45 ° C. was obtained at a total calorific value of 4.16 × 10 ⁶ Kcal / hr. in this case,
The amount of heat supplied to the first generator 01 is (1.0 to 1.1) × 10 ⁶ Kcal
/ Hr. The calorific value of the cold water having a temperature of 10 ° C. obtained by the heat exchanger 48 was 2.42 × 10 ⁶ Kcal / hr.

This result was higher than the coefficient of performance of any conventional heat pump. The heat transfer area as the size of the device is as follows: the first generator and the second generator: 100 m ² , the second evaporator and the second absorber: 180 m ² , the third generator and the third condenser. : 330 m ² , third evaporator and third absorber: 440 m ² .

[0041]

[Table 1]

[0042]

As described above, according to the present invention, a heat pump system having high thermal efficiency can be constructed.

[Brief description of drawings]

FIG. 1 is a flow sheet of a first aspect of the present invention.

FIG. 2 is a flow sheet of a second aspect of the present invention.

FIG. 3 is a flow sheet of a third aspect of the present invention.

[Explanation of reference numerals] 01 ... first generator, 02 ... first condenser, 1 ... second generator, 2 ... second condenser, 3 ... second evaporator, 4 ... second absorber, 11 ... second 3 generator, 12 ... 3rd condenser, 13 ... 3rd
Evaporator, 14 ... Third absorber, 23 ... First heat medium circulation path, 2
4 ... 2nd heat medium circulation path, 31 ... (intermediate) mechanical compressor, 4
5 ... 4th heat medium circulation path, 46 ... 3rd heat medium circulation path, 60 ... 5th heat conducting path, 62 ... 6th heat conducting path.

Claims (6)

[Claims] 1. A first absorption heat pump is constituted by a first generator and a first condenser using a refrigerant and an absorbent, respectively, and a second generator, a second condenser, a second evaporator, and a third evaporator. The absorber constitutes the second absorption heat pump, the third generator,
The third condenser, the third evaporator, and the third absorber constitute a third absorption heat pump, and the vapor generated in the first generator is passed through the first condenser in the second generator, and the condensed liquid To the second evaporator, the vapor generated in the second generator is passed through the second condenser in the third generator, the condensate is led to the second evaporator, and the external drive heat source is supplied to the first generator. As a driving heat source, a first heat medium circulation path that circulates between the second absorber and the third generator is configured, and heat of the heat medium that is heated by the second absorber and passes through the first heat medium circulation path. , And heat of the vapor generated in the second generator and transferred to the heater of the third generator as a driving heat source of the third generator, and at least one of the third condenser and the third absorber. And a second evaporator are connected by a second heat medium circulation path to serve as a heating source for the second evaporator, and the third evaporator is used. A triple-effect heat pump characterized in that the generated vapor is pressurized by a mechanical compressor to be condensed in the third absorber. 2. The triple effect heat pump according to claim 1, wherein in the second heat medium circulation path, the heat medium passes through both the third absorber and the third condenser in this order and then reaches the second evaporator. 3. A first absorption type heat pump is constituted by a first generator and a first condenser using a refrigerant and an absorbent, respectively, and a second generator, a second condenser, a second evaporator and a third condenser. The absorber constitutes the second absorption heat pump, the third generator,
The third condenser, the third evaporator, and the third absorber constitute a third absorption heat pump, and the vapor generated in the first generator is passed through the first condenser in the second generator, and the condensed liquid To the second evaporator, the vapor generated in the second generator is passed through the second condenser in the third generator, the condensate is led to the second evaporator, and the external drive heat source is supplied to the first generator. As a driving heat source, a first heat medium circulation path that circulates between the second absorber and the third generator is configured, and heat of the heat medium that is heated by the second absorber and passes through the first heat medium circulation path. , And the heat of the vapor generated in the second generator and transferred to the heater of the third generator is used as the driving heat source of the third generator, and the space between the third evaporator and the second evaporator is A third heat medium circulation path is connected to serve as a heating source for the second evaporator, and the vapor generated in the third evaporator is boosted by a mechanical compressor. The triple effect heat pump is characterized in that it is configured to condense in the third absorber. 4. The triple-effect heat pump according to claim 3, wherein the third absorber and the third condenser are connected by a fourth heat medium circulation path. 5. A first absorption heat pump is constituted by a first generator and a first condenser using a refrigerant and an absorbent, respectively, and a second generator, a second condenser, a second evaporator, and a third evaporator. The absorber constitutes the second absorption heat pump, the third generator,
The third condenser, the third evaporator, and the third absorber constitute a third absorption heat pump, and the vapor generated in the first generator is passed through the first condenser in the second generator, and the condensed liquid To the second evaporator, the vapor generated in the second generator is passed through the second condenser in the third generator, the condensate is led to the second evaporator, and the external drive heat source is supplied to the first generator. As a driving heat source, a first heat medium circulation path that circulates between the second absorber and the third generator is configured, and heat of the heat medium that is heated by the second absorber and passes through the first heat medium circulation path. , And the heat of the vapor generated in the second generator and transferred to the heater of the third generator is used as the driving heat source of the third generator, and the heat between the third absorber and the third condenser is The heat source of the second evaporator is connected to the fifth heat conducting path, and the heat source of the third evaporator is connected to the sixth heat conducting path. And by heating incoming respectively, these fifth Netsushirubero and sixth Netsushirubero the fourth
A triple-effect heat pump, which is independent of the heat medium circulation path, and is configured such that vapor generated in the third evaporator is pressurized by a mechanical compressor to be condensed in the third absorber. 6. The refrigerant and the absorbent in the first effect and the second effect are TFE-E181, and the refrigerant and the absorbent in the third effect are water-ammonia or R134a-E181.
The triple effect heat pump according to claim 1, 3 or 5.