JP2002098436A - Freezing apparatus - Google Patents

Abstract

PROBLEM TO BE SOLVED: To improve the efficiency of an apparatus as a whole by effectively utilizing refrigerant vapor, when the need for cooling using heat on the side of utilization is small. SOLUTION: There is provided a freezing circuit (20) of an absorption freezing cycle, that includes a producer (23), a condenser (24), a vaporizer (21), and an absorber (22). A vapor turbine (40) is provided, which produces power by receiving water vapor produced in the producer (23) of the freezing circuit (20), and returns the water vapor to the absorber (22). An auxiliary power generator (50) is coupled to the vapor turbine (23). The producer (23) of the freezing circuit (20) communicates with the condenser (24) and the vapor turbine (40) through a high pressure three-way valve (41), and the absorber (22) is communicated with the vaporizer (31) and the power generator (40) through a low- pressure three-way valve (43). Water vapor from the producer (23) flows through the condenser (24), corresponding to a cold heat load, and excess water vapor flows through the vapor turbine (23).

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

[0001] The present invention relates to a refrigeration apparatus,
In particular, the present invention relates to a refrigerating device that generates cold heat by being driven by exhaust heat.

[0002]

2. Description of the Related Art Conventionally, as disclosed in Japanese Patent Publication No. 5-28752, an absorption refrigerating apparatus includes a generator, an absorber, an evaporator, and a condenser.
This absorption refrigeration system inputs heat energy to the generator,
It is configured to generate cold heat in the evaporator.

On the other hand, some cogeneration systems include an absorption refrigeration system. This cogeneration system generally generates electric power by driving a generator with a heat engine such as a diesel engine, a gas engine, or a gas turbine, and drives an absorption refrigeration system using exhaust heat of the heat engine to generate a cold heat. To perform cooling or the like.

In this cogeneration system equipped with an absorption refrigeration system utilizing waste heat, power demand exists throughout the year, but cooling operation is performed only in summer. That is, since cooling is not required in the intermediate period or winter, even if the refrigerating apparatus is driven by exhaust heat, the generated cool heat is not used. For this reason, in the conventional cogeneration system, the refrigeration system is not operated during a period in which cooling is not required.

[0005]

However, when the refrigeration system is stopped as described above, the exhaust heat from the heat engine during that time is not sufficiently utilized. For example, when a cogeneration system is installed in an office building, this problem becomes serious.

In other words, since there is little demand for hot water supply in an office building, exhaust heat is hardly used especially in the interim period, and the exhaust heat must be discarded as it is. For this reason, the conventional cogeneration system has a problem that energy cannot be effectively used. In addition, the above-mentioned conventional cogeneration system has a problem that it is difficult to recover facility costs by reducing operating costs.

SUMMARY OF THE INVENTION The present invention has been made in view of the above circumstances, and has as its object to improve the efficiency of the entire apparatus by effectively utilizing refrigerant vapor when the demand for cooling heat on the user side is small. It is.

[0008]

Specifically, as shown in FIG. 1, the present invention has a generator (23), a condenser (24), an evaporator (21), and an absorber (22). The refrigeration circuit (20) of the absorption refrigeration cycle is provided. Furthermore, the refrigeration circuit (2
A power generator (40) is provided which receives the refrigerant vapor generated by the generator (23) of (0) to generate power and returns the refrigerant vapor to the absorber (22).

Another invention provides the above power generator (40).
Is connected to a generator (50). When the refrigeration circuit (20) requires cold heat, the refrigerant vapor of the generator (23) is supplied to the condenser (24) to generate cold heat in the evaporator (21). When the amount becomes equal to or less than the predetermined amount, a part or all of the refrigerant vapor of the generator (23) is supplied to the power generator (40).

In another aspect, the generator (23) of the refrigeration circuit (20) communicates with a condenser (24) and a power generator (40), and the absorber (22) is connected to an evaporator ( A branch mechanism (41, 43) is provided for communicating with the power generator (40) and the power generator (21). The branch mechanism (41, 43) is configured to allow the refrigerant vapor of the generator (23) to flow through the condenser (24) in response to the cooling load, and to allow the excess refrigerant vapor to flow through the power generator (40). Is configured.

Further, the present invention provides at least an absorber (22)
May be provided with a heat take-out mechanism (70) for taking out the heat generated in step (1).

Further, the heating of the solution in the generator (23) may be configured to be able to use both exhaust heat and combustion heat.

Further, the refrigeration circuit (20) may be configured as a single-effect cycle.

Further, the refrigeration circuit (20) may be configured in a multiple effect cycle. In this case, the refrigerant vapor of the first generator (23a) may be supplied to the power generator (40). Further, the refrigerant vapor of the second generator (23b) may be supplied to the power generator (40).

That is, in the present invention, when cold heat is generated, the refrigerant evaporates in the evaporator (21) to generate cold heat. The gas refrigerant (water vapor) of the evaporator (21) is
Absorbed in the concentrated solution tube (33) of 2), the concentrated solution becomes a dilute solution.

The dilute solution in the absorber (22) is supplied to the generator (2)
3), and is heated by, for example, exhaust heat of a gas turbine. Then, the water evaporates from the dilute solution to form a concentrated solution. In the generator (23), when the combustion exhaust gas decreases, the fuel may be burned, and the heat of the combustion may be used to evaporate the water content of the absorbing solution.

The concentrated solution in the generator (23) is supplied to the absorber (2)
2), the concentrated solution absorbs the gas refrigerant. Also,
The gas refrigerant of the generator (23) moves to the condenser (24) and is condensed, and the condensed liquid refrigerant moves to the evaporator (21) and repeats the above operation.

The cold heat of the evaporator (21) cools, for example, a low-temperature fluid and flows to a fan coil unit on the use side.
Cool the room.

On the other hand, in an intermediate period or a winter period when there is no cooling load, for example, the generator (23) is operated by the branch mechanism (41, 43).
The water vapor (gas refrigerant) generated in does not flow to the condenser (24) but enters the power generator (40). The steam introduced into the power generator (40) expands and rotates the power generator (40). Thereafter, the expanded steam returns to the absorber (22) and is absorbed by the concentrated solution.

Then, the torque of the power generator (40) drives the generator (50), and the generator (50) generates power. The power of the generator (50) assists, for example, the power demand of office buildings.

When the cooling load is not so large, a part of the steam (gas refrigerant) generated by the generator (23) is supplied to the condenser (24), and the remaining steam is supplied to the power generator ( Supply to 40). That is, the generator (50) is driven at the same time when the evaporator (21) generates cold heat.

The refrigeration circuit (20) may have a multiple effect cycle instead of a single effect cycle. that time,
In the first generator (23a) and the second generator (23b), the dilute solution and the refrigerant vapor are separated to generate a concentrated solution.

[0023] The refrigerant vapor of the first generator (23a) may be supplied to a power generator (40) to generate power. Further, the refrigerant vapor of the second generator (23b) may be supplied to the power generator (40) to generate power.

Further, a medium-temperature fluid flows through the absorber (22), and the medium-temperature fluid is absorbed by the medium-temperature fluid extraction mechanism (70). Then, the medium temperature fluid may flow into the room to perform heating.

[0025]

Therefore, according to the present invention, the refrigerant vapor generated in the generator (23) is supplied to the power generator (40) to drive the generator (50). In the case where there is no use of the cold heat in 20) or when the use of the cold heat is small, power can be generated by using the exhaust heat. As a result, effective use of waste heat can be further achieved, and at the same time, efficiency can be improved by performing bottoming power generation.

That is, even when the cooling load is small or when there is no cooling load, the exhaust heat of the gas turbine or the like can be effectively used. As a result, the combustion energy input to the gas turbine or the like can be effectively used, and the efficiency of the entire cogeneration system (11) can be improved.

When the refrigerant vapor is distributed to the condenser (24) and the power generator (40) in accordance with the cooling load, the operation rate can be further improved and the efficiency can be further improved. be able to.

If the heating of the solution can be performed by using both the exhaust heat and the fuel heat, the operation can be performed even when there is no exhaust heat, and the reliability can be improved.

Further, when the heat extraction mechanism (70) is provided, the power generation and the heating operation can be performed at the same time, so that the efficiency can be further improved.

When the refrigeration circuit (20) is a single-effect system, the configuration can be simplified.

When the refrigeration circuit (20) is a multiple effect system, the efficiency can be further improved.

When the refrigeration circuit (20) is a multiple effect system and the power generator (40) is driven by the refrigerant vapor of the first generator (23a), the pressure difference can be increased. In addition, power generation efficiency can be improved.

[0033]

Embodiment 1 Hereinafter, Embodiment 1 of the present invention will be described in detail with reference to the drawings.

As shown in FIG. 1, the refrigeration system (10) of the present embodiment constitutes a cogeneration system (11). The cogeneration system (11) is installed in an office building.

The refrigeration system (10) includes a refrigeration circuit (20), and is configured to receive supply of exhaust heat from a gas turbine (not shown). That is, the refrigeration circuit (2
0) is configured to be driven by the exhaust heat of the gas turbine to generate cold heat, and is configured as a so-called exhaust heat drive type. The cold heat of the refrigeration circuit (20) is used for cooling in a building. The gas turbine drives a main generator. The power generated by the main generator covers all or part of the power demand of the office building.

The refrigeration circuit (20) is configured as a single-effect absorption refrigeration cycle using water as a refrigerant and an aqueous solution of lithium bromide as an absorption solution. The refrigeration circuit (20) is configured to be driven by combustion heat of a fuel such as natural gas while being connected to a gas turbine. However, the driving of the refrigeration circuit (20) is mainly used when the exhaust heat of the gas turbine is used, and the combustion heat of the fuel is used when it is necessary to supplementarily use the heat.

The refrigeration circuit (20) includes an evaporator (21), an absorber (22), a generator (23), and a condenser (24). Further, the refrigeration circuit (20) includes a solution heat exchanger (25)
And an exhaust gas heat exchanger (26).

The evaporator (21) is configured to evaporate the liquid refrigerant (water) to generate cold heat. Although not shown, the evaporator (21) includes a heat transfer tube and a refrigerant disperser. Although not shown in the heat transfer tube of the evaporator (21),
A low temperature circuit through which a low temperature fluid such as cold water flows is connected. The refrigerant disperser disperses the liquid refrigerant (water) accumulated in the evaporator (21) to the heat transfer tube. That is, the evaporator (21)
Is configured to exchange heat between a low-temperature fluid flowing in the heat transfer tube and a liquid refrigerant (water).

The evaporator (21) is connected to the absorber (22) by a low-pressure first steam pipe (30). Then, the gas refrigerant (steam) of the evaporator (21) moves to the absorber (22) via the first steam pipe (30).

Although not shown, the absorber (22) includes a heat transfer tube and a solution sprayer. Although not shown, the heat transfer tube of the absorber (22) is connected to a cooling circuit for cooling the solution whose temperature has increased due to the heat of absorption. The solution sprayer sprays a highly concentrated aqueous solution of lithium bromide (concentrated solution) onto the heat transfer tube from above the heat transfer tube. That is, the absorber (22) is configured such that the concentrated solution sucks the gas refrigerant (water vapor) of the evaporator (21).

The absorber (22) is connected to a generator (23) via a dilute solution pipe (31). The diluted solution tube (31)
Is provided with a solution pump (32). The dilute solution pipe (31) is branched into a first branch pipe (31a) and a second branch pipe (31b) downstream of the solution pump (32).
The first branch pipe (31a) and the second branch pipe (31b) are connected to the generator (23). The first branch pipe (31a) is provided with an exhaust gas heat exchanger (26) while the second branch pipe (31a) is provided with the second branch pipe (31a).
The branch pipe (31b) is provided with a solution heat exchanger (25).

The exhaust gas heat exchanger (26) exchanges heat between the combustion exhaust gas discharged from a gas turbine (not shown) and the dilute solution flowing through the first branch pipe (31a) to heat the dilute solution. It is configured as follows. That is, the exhaust heat is supplied to the dilute solution.

A dilute solution is fed into the generator (23) through a dilute solution pipe (31). The generator (23) is configured to evaporate water from the dilute solution to generate a concentrated solution. That is, the generator (23) separates the dilute solution into a lithium bromide aqueous solution and water vapor.

The generator (23) receives combustion heat from a gas burner or the like. The heat of combustion heats the aqueous solution of lithium bromide in the generator (23). The generator (23) is also configured to evaporate water from the dilute solution by this heating to generate a concentrated solution.

The generator (23) is connected to the absorber (22) via a concentrated solution pipe (33). The concentrated solution tube (33)
Is connected to the solution sprayer of the absorber (22). The solution heat exchanger (25) is configured to exchange heat between the dilute solution flowing through the dilute solution pipe (31) and the concentrated solution flowing through the concentrated solution pipe (33).

Further, the generator (23) is connected to a condenser (24) via a high-pressure second steam pipe (34). That is, the gas refrigerant (steam) of the generator (23) is sent into the condenser (24) via the second steam pipe (34).

Although not shown, the condenser (24) is provided with a heat transfer tube. Although not shown, a cooling circuit connected to the heat transfer tube of the absorber (22) is connected to the heat transfer tube of the condenser (24). The condenser (24) is configured to exchange heat between a medium-temperature fluid such as cooling water flowing in the heat transfer tube and a gas refrigerant (steam) outside the heat transfer tube to condense the gas refrigerant (steam). I have.

The condenser (24) is connected to an evaporator (21) via a liquid refrigerant pipe (35). The evaporator (21)
The liquid refrigerant (water) of the condenser (24) is fed through the liquid refrigerant pipe (35). Then, as described above, the evaporator (21) causes heat exchange between the low-temperature fluid in the heat transfer tube and the liquid refrigerant (water), and the liquid refrigerant (water) evaporates to generate cold heat.

In the low-temperature circuit, the heat transfer tube of the evaporator (21) in the refrigeration circuit (20) is connected to an indoor heat exchanger of a fan coil unit (not shown). That is,
The low-temperature circuit is configured to circulate a low-temperature fluid between the heat transfer tube of the evaporator (21) and the indoor heat exchanger of the fan coil unit. The fan coil unit is installed indoors. The fan coil unit is configured to cause indoor air to exchange heat with a low-temperature fluid in an indoor heat exchanger and blow cooling air into the room.

The refrigeration system (10) is characterized by a steam turbine (40) and an auxiliary generator (5)
0) is provided.

The steam turbine (40) includes a refrigeration circuit (20)
And a power generator that generates power by receiving steam (gas refrigerant) from the generator (23). That is, a high-pressure three-way valve (41) as a branch mechanism is provided in the second steam pipe (34) between the generator (23) and the condenser (24) in the refrigeration circuit (20). . The high-pressure three-way valve (41) includes:
The steam inlet pipe (42) of the steam turbine (40) is connected. The high-pressure three-way valve (41) supplies the steam of the generator (23) to one of the condenser (24) and the steam turbine (40), and supplies the steam of the generator (23) to the condenser (24). And the steam turbine (40).

A superheater (45) is connected to the steam inlet pipe (42).
Is arranged. The superheater (45) is configured to be supplied with exhaust heat of the gas turbine and superheat steam (gas refrigerant) supplied to the steam turbine (40).

In the first steam pipe (30) between the evaporator (21) and the absorber (22) in the refrigeration circuit (20), a low-pressure three-way valve (43) as a branch mechanism is provided. Is provided. The low-pressure three-way valve (43) is connected to a steam outlet pipe (44) of a steam turbine (40). The low-pressure three-way valve (4
3) returns either the steam of the steam turbine (40) or the steam of the evaporator (21) to the absorber (22) and absorbs the steam of both the steam turbine (40) and the evaporator (21). It is configured to return to the vessel (22).

The steam turbine (40) includes a generator (23)
The steam is expanded by receiving the steam, and the steam is rotated by the expansion of the steam to generate power. The expanded steam returns to the absorber (22) via the steam outlet pipe (44) and the first steam pipe (30).

That is, when the cooling heat generated in the refrigeration circuit (20) becomes unnecessary, for example, in winter or the like, the high-pressure three-way valve (41) and the low-pressure three-way valve (43) are switched to transfer steam to the steam turbine. Supply to (40), steam turbine (40)
To generate power.

An auxiliary generator (50) is connected to the output shaft (46) of the steam turbine (40). The auxiliary generator (50) is configured to generate power by the power of the steam turbine (40). The power generated by the auxiliary generator (50) simply supplements a part of the power demand of the office building, and does not bear the main power.

<Operation> Next, the operation of the refrigeration system (10) in the cogeneration system (11) will be described.

The refrigeration system (10) is driven by the heat energy of the combustion exhaust gas to generate cold heat. That is, the gas turbine is driven by the combustion gas, and the combustion exhaust gas of the combustion gas is supplied to the refrigeration system (10). On the other hand, the power generated by the gas turbine is transmitted to the main generator. The power generated by the main generator is supplied to an office building.

The operation of the refrigeration circuit (20) in the refrigeration apparatus (10) will now be described. The refrigeration system (10) is always operated regardless of the presence or absence of a cooling load.
Also, during the cooling operation that generates cold heat, the high-pressure three-way valve (41)
The low-pressure three-way valve (43) is switched to the solid line side in FIG.

First, at the same time as the low-temperature fluid of the low-temperature circuit flows through the heat transfer tubes of the evaporator (21), a liquid refrigerant (water) is sprayed on the heat transfer tubes. The liquid refrigerant (water) absorbs heat from the low-temperature fluid flowing through the heat transfer tube and evaporates. The gas refrigerant (water vapor) evaporated in the evaporator (21) passes through the first steam pipe (30),
Move to absorber (22).

In the absorber (22), a concentrated solution tube (33)
Supplies a concentrated solution. The gas refrigerant (water vapor) flowing into the absorber (22) is absorbed by the concentrated solution, and the concentrated solution becomes a dilute solution. On the other hand, a medium-temperature fluid as cooling water flows through the heat transfer tube of the absorber (22), and the medium-temperature fluid absorbs the heat of absorption when the gas refrigerant (steam) is absorbed by the concentrated solution.

The dilute solution in the absorber (22) flows through the dilute solution pipe (31) by the solution pump (32) and is sent to the generator (23). The dilute solution in the dilute solution pipe (31) is supplied to the first branch pipe (31).
a) and the second branch pipe (31b). that time,
Most of the dilute solution flows through the first branch pipe (31a).

The dilute solution flowing through the first branch pipe (31a) exchanges heat with the exhaust gas of the gas turbine in the exhaust gas heat exchanger (26). By this heat exchange, exhaust heat of the gas turbine is given to the dilute solution, and the dilute solution is heated.
The heated dilute solution flows into the generator (23).

The dilute solution flowing through the second branch pipe (31b) exchanges heat with the concentrated solution in the concentrated solution pipe (33) in the solution heat exchanger (25). By this heat exchange, the heat energy held by the concentrated solution is recovered by the diluted solution, and the diluted solution is heated. Then, the dilute solution absorbed by the solution heat exchanger (25)
It flows into the generator (23).

In the generator (23), water evaporates from the dilute solution as an aqueous solution of lithium bromide, and the aqueous solution of lithium bromide becomes a concentrated solution. In the generator (23), the fuel (natural gas) may be burned by a gas burner, and the heat of the combustion may be used to evaporate the water content of the aqueous lithium bromide solution. For example, when the power demand is small, it is also assumed that the combustion exhaust gas decreases and the aqueous solution of lithium bromide in the generator (23) does not become highly concentrated. In this case, the lithium bromide aqueous solution is heated using the heat of combustion of natural gas.

The concentrated solution from the generator (23) is sent to the absorber (22) via the concentrated solution pipe (33). At that time, the concentrated solution radiates heat to the dilute solution in the solution heat exchanger (25) and enters the absorber (22) after being decompressed. This concentrated solution absorbs the gas refrigerant (water vapor).

Gas refrigerant (steam) of the generator (23)
Moves to the condenser (24) via the second steam pipe (34). The medium-temperature fluid after absorbing heat in the absorber (22) flows through the heat transfer tube of the condenser (24). In the condenser (24), heat exchange occurs between the gas refrigerant (steam) and the medium temperature fluid of the heat transfer tube. Then, the gas refrigerant (steam) condenses, and the medium-temperature fluid absorbs the heat of condensation of the gas refrigerant (steam).

Liquid refrigerant (water) condensed in the condenser (24)
Passes through the liquid refrigerant pipe (35) and is decompressed, and then the evaporator (2
Move to 1) and repeat the above operation.

The low-temperature fluid of the low-temperature circuit is supplied to an evaporator (21)
Radiates heat to the liquid refrigerant (water) while flowing through the heat transfer tubes of
Cooled. The low-temperature fluid flows to the fan coil unit on the use side to cool the room. That is, cooling is performed by the cold generated by the refrigeration circuit (20).

On the other hand, in an intermediate period or a winter period when there is no cooling load, the high-pressure three-way valve (41) and the low-pressure three-way valve (43) are switched to the broken line side in FIG. Then, the steam (gas refrigerant) generated in the generator (23) does not flow to the condenser (24) but flows through the steam inlet pipe (42). Then, the steam is superheated by the combustion exhaust gas of the gas turbine in the superheater (45), and then enters the steam turbine (40). The steam (gas refrigerant) introduced into the steam turbine (40) expands and rotates the steam turbine (40). Thereafter, the expanded water vapor (gas refrigerant) flows through the vapor outlet pipe (44), returns to the absorber (22), and is absorbed by the concentrated solution.

Then, the torque of the steam turbine (40) is taken out via the output shaft (46) and is supplied to the auxiliary generator (5).
0), and the auxiliary generator (50) generates electric power. The power of the auxiliary generator (50) supplements the power demand of the office building.

When the cooling load is not so large, part of the steam (gas refrigerant) generated by the generator (23) is supplied to the condenser (24), and the remaining steam is supplied to the steam turbine (40). ). That is, at the same time that the low-temperature fluid is generated by the evaporator (21), the auxiliary generator (50) is driven, and the power of the auxiliary generator (50) is used for the power demand of the office building.

<Effects of First Embodiment> As described above, according to the present embodiment, the steam (gas refrigerant) generated by the generator (23) is supplied to the steam turbine (40) and the auxiliary generator (5
In the case where the refrigeration circuit (20) is not used or the chilled water is not used because the refrigeration circuit (20) is driven, power can be generated by using the exhaust heat. As a result, effective use of waste heat can be further achieved, and at the same time, efficiency can be improved by performing bottoming power generation.

That is, even when the cooling load is small or when there is no cooling load, the exhaust heat of the gas turbine or the like can be effectively used. As a result, the combustion energy input to the gas turbine or the like can be effectively used, and the efficiency of the entire cogeneration system (11) can be improved.

Further, since the refrigerant vapor is distributed to the condenser (24) and the power generator (40) in accordance with the cooling load, the operation rate can be further improved, and higher efficiency can be achieved. Can be planned.

If the solution can be heated by using both exhaust heat and fuel heat, operation can be performed even when there is no exhaust heat, and reliability can be improved.

Further, since the refrigeration circuit (20) is configured as a single-effect absorption refrigeration system, the configuration can be simplified.

Further, since the refrigerant vapor supplied to the power generator is heated by the exhaust heat in the superheater (45), the power generation efficiency can be further improved.

[0079]

Second Embodiment Next, a second embodiment of the present invention will be described in detail with reference to the drawings.

As shown in FIG. 2, a refrigeration apparatus (10) of the present embodiment is different from the refrigeration circuit (20) of the single-effect absorption refrigeration system of the first embodiment in that a refrigeration circuit (20) of This applies the refrigeration circuit (20) of the absorption refrigeration system. That is, the refrigeration circuit (20) of the present embodiment includes the high temperature generator (23a) and the low temperature generator (23b) that constitute the generator (23) of the first embodiment.

The high-temperature generator (23a) is a first generator and is connected to the absorber (22) via a dilute solution pipe (31). The dilute solution pipe (31) is provided with a solution pump (32) and a low-temperature heat exchanger (25a) which is a solution heat exchanger. The dilute solution pipe (31) is connected to the low-temperature heat exchanger (25
a) On the downstream side, the first branch pipe (31a) and the second branch pipe (31b) are branched. The first branch pipe (31a) is provided with an exhaust gas heat exchanger (26), while the second branch pipe (31b) is provided with a high-temperature heat exchanger (25b) as a solution heat exchanger. Is provided.

The high temperature generator (23a) is configured to separate the dilute solution into a medium concentration aqueous solution of lithium bromide (medium solution) and water vapor. The high-temperature generator (23a) receives heat of combustion from a gas burner or the like, and heats the aqueous lithium bromide solution by the heat of combustion.

Further, the high-temperature generator (23a) is connected to a low-temperature generator (23b) via a medium solution pipe (36) and a high-pressure third steam pipe (37). The middle solution pipe (36) is connected to a high-temperature heat exchanger (25b) on the way, and is connected to a high-temperature generator (23).
The medium solution in a) is decompressed and led to the low temperature generator (23b). The high-temperature heat exchanger (25b) is configured to exchange heat between the dilute solution flowing through the second branch pipe (31b) of the dilute solution pipe (31) and the middle solution flowing through the middle solution pipe (36). I have.

The low-temperature generator (23b) is a second generator and is provided with a heat transfer tube (not shown). The heat transfer tube of the low-temperature generator (23b) is the third steam tube (37).
Is connected, and the steam generated in the high-temperature generator (23a) flows.

The low-temperature generator (23b) is configured to exchange heat between steam in the heat transfer tube and the middle solution outside the heat transfer tube. By this heat exchange, the middle solution is heated and the water evaporates, the concentration increases and the solution becomes a concentrated solution.

The low-temperature generator (23b) is connected to a concentrated solution tube (3
3) is connected to the absorber (22). The low-temperature heat exchanger (25a) is connected to the concentrated solution pipe (33) on the way. Then, the concentrated solution of the low-temperature generator (23b) is decompressed and sprayed on the heat transfer tube of the absorber (22). The low-temperature heat exchanger (25a) includes a dilute solution flowing through a dilute solution pipe (31),
It is configured to exchange heat with the concentrated solution flowing through the concentrated solution pipe (33).

The low-temperature generator (23b) is provided with a liquid pipe (3
8) and a condenser (24) through the medium-pressure second steam pipe (34)
It is connected to the. The liquid pipe (38) is connected to the low-temperature generator (23).
b) It is connected to the heat transfer tube. And the above liquid tube (3
In (8), the refrigerant condensed in the heat transfer tube of the low-temperature generator (23b) is led to the condenser (24) after being decompressed. The second steam pipe (34) guides the gas refrigerant (steam) of the low-temperature generator (23b) to the condenser (24).

On the other hand, as in the first embodiment, the second steam pipe (34) and the first steam pipe (30) are
0) The steam inlet pipe (42) and the steam outlet pipe (44) are connected. That is, the steam turbine (40) is configured to supply the steam (gas refrigerant) of the low-temperature generator (23b). Other configurations are the same as in the first embodiment.

FIG. 2 shows a low-temperature circuit (60) and a cooling circuit (70). The low-temperature circuit (60) and the cooling circuit (70) are not shown in the first embodiment.

<Operation> Next, the operation of the refrigeration circuit (20) will be described.

First, in the evaporator (21), the liquid refrigerant (water) absorbs heat from the low-temperature fluid in the low-temperature circuit (60) and evaporates to cool the low-temperature fluid. The evaporated gas refrigerant (steam) passes through the first steam pipe (30) and moves to the absorber (22).

In the absorber (22), the concentrated solution absorbs the gas refrigerant (water vapor) and becomes a dilute solution. Further, in the absorber (22), the medium temperature fluid of the cooling circuit (70) absorbs the heat absorbed in the absorption process.

The dilute solution of the absorber (22) flows through the dilute solution pipe (31) to the high temperature generator (23a). At this time, the dilute solution exchanges heat with the concentrated solution in the low-temperature heat exchanger (25a), and thereafter, the dilute solution flowing through the first branch pipe (31a) has the exhaust heat diluted by the exhaust gas heat exchanger (26). The dilute solution applied to the solution and flowing through the second branch pipe (31b) exchanges heat with the middle solution in the high-temperature heat exchanger (25b).

In the high-temperature generator (23a), water evaporates from the aqueous lithium bromide solution (dilute solution) to form an intermediate solution. In the high-temperature generator (23a), when the amount of combustion exhaust gas is small, the solution is heated by heat of combustion of natural gas or the like.

The middle solution of the high temperature generator (23a) flows through the middle solution pipe (36) to the low temperature generator (23b). on the other hand,
The gas refrigerant (steam) of the high temperature generator (23a)
It flows through the heat transfer tube of the low-temperature generator (23b) via the steam tube (37).

In the low-temperature generator (23b), the gas refrigerant (steam) flowing through the heat transfer tube is condensed, and the heat of condensation heats the aqueous lithium bromide solution. Then, water evaporates from the aqueous lithium bromide solution to form a concentrated solution. The concentrated solution of the low-temperature generator (23b) is supplied to the absorber (22) through the concentrated solution pipes (38) (33).

The gas refrigerant (steam) of the low-temperature generator (23b) moves to the condenser (24) via the second steam pipe (34), and is absorbed by the medium-temperature fluid after absorbing heat by the absorber (22). Refrigerant (water vapor) condenses.

The refrigerant condensed in the low-temperature generator (23b) moves to the condenser (24) through the liquid pipe (38), and evaporates through the liquid refrigerant pipe (35) together with the refrigerant condensed in the condenser (24). Move to the container (21).

On the other hand, when there is no demand for the cold heat of the refrigeration circuit (20) or when the demand for the cold heat is small, the high-pressure three-way valve (41) and the low-pressure three-way valve (43) are controlled, and the low-temperature generator ( twenty three
b) The steam (gas refrigerant) is supplied to the steam turbine (40). By driving the steam turbine (40), the auxiliary generator (5
At 0), electric power is generated. Other functions and effects are the same as those of the first embodiment.

An example of the state of the refrigerant in the refrigeration circuit (20) will now be described.

First, as shown in FIG. 2A, the gas refrigerant (steam) flowing out of the high temperature generator (23a) has a temperature of 132 ° C. and a pressure of 59.2 kPa. Also,
As shown in FIG. 2B, the gas refrigerant (steam) flowing out of the low-temperature generator (23b) has a temperature of 81 ° C. and a pressure of 6.6 kPa.

When the power is generated by the auxiliary generator (50), as shown in FIG. 2C, the gas refrigerant (steam) supplied from the low temperature generator (23b) to the steam turbine (40) is:
The temperature is 230 ° C. and the pressure is 6.6 kPa. Then, as shown in FIG. 2D, the temperature of the gas refrigerant (steam) flowing out of the steam turbine (40) and flowing to the absorber (22) is 5 ° C., and the pressure is 0.87 kPa. Therefore, the refrigerant has a pressure difference sufficient to drive the steam turbine (40).

Therefore, according to the present embodiment, since the refrigeration circuit (20) is configured as a multiple effect absorption refrigeration system, the efficiency can be further improved.

[0104]

Third Embodiment Next, a third embodiment of the present invention will be described in detail with reference to the drawings.

As shown in FIG. 3, in the refrigerating apparatus (10) of the present embodiment, the steam (gas refrigerant) of the low-temperature generator (23b) is supplied to the steam turbine (40) in the second embodiment. Instead, the steam (gas refrigerant) of the high-temperature generator (23a) is supplied to the steam turbine (40).

That is, the third steam pipe (37) connected to the high-temperature generator (23a) is provided with a high-pressure three-way valve. The high-pressure three-way valve (41) is connected to a steam inlet pipe (42) of a steam turbine (40). The second
The steam pipe (34) is connected only to the low-pressure generator (23) and the condenser (24).

Therefore, when there is no demand for the cold heat of the refrigeration circuit (20) or when the demand for the cold heat is small, the high pressure 3
The one-way valve (41) and the low-pressure three-way valve (43) are controlled to supply steam (gas refrigerant) from the high-pressure generator (23) to the steam turbine (40). The steam turbine (40) is driven to generate electric power by the auxiliary generator (50). Other configurations, operations, and effects are the same as those of the second embodiment.

An example of the state of the refrigerant in the refrigeration circuit (20) will now be described.

First, as shown in FIG. 3A, the gas refrigerant (steam) flowing out of the high temperature generator (23a) has a temperature of 1
32 ° C. and pressure is 59.2 kPa.

When power is generated by the auxiliary generator (50), as shown in FIG. 3B, the gas refrigerant (steam) supplied from the low-temperature generator (23b) to the steam turbine (40) is:
The temperature is 230 ° C. and the pressure is 59.2 kPa.
Then, as shown in FIG. 3C, the gas refrigerant (steam) flowing out of the steam turbine (40) and flowing to the absorber (22) is:
The temperature is 5 ° C. and the pressure is 0.87 kPa. Therefore, the refrigerant has a pressure difference sufficient to drive the steam turbine (40).

Therefore, according to this embodiment, when the steam turbine (40) is driven by the steam of the high-temperature generator (23a), the pressure difference can be increased, and the power generation efficiency can be improved. Can be.

[0112]

In other embodiments of the present invention, the cooling circuit (70) is configured to absorb heat of absorption and heat of condensation to cool the absorbing solution and the refrigerant. However, the cooling circuit (70) may constitute a heat extraction mechanism as one embodiment of the present invention. That is, the cooling circuit (70) may be connected to a water heater, a fan coil unit, or the like, and supply a medium-temperature fluid that is hot water to the water heater or the fan coil unit. At that time, the cooling circuit (70) passes only through the absorber (22),
You may comprise so that only absorption heat may be absorbed. And
The heat of condensation is absorbed in a separate cooling circuit.

In particular, in this case, a medium-temperature fluid can be supplied even when only power generation is performed without using cold heat. That is, for example, in the first embodiment, when only the auxiliary generator (50) generates power using all the steam, the steam flowing from the steam turbine (40) to the absorber (22) is absorbed by the solution. This dilute solution flows to the generator (23), where the water vapor is separated into a concentrated solution. Since this operation is repeated, absorbed heat is always generated, so that heating or the like can be always performed.

Although the refrigeration circuit (20) uses water as a refrigerant and an aqueous solution of lithium bromide as an absorbing solution, the refrigeration circuit (20) may use ammonia as a refrigerant and water as an absorbent.

The low-temperature fluid of the low-temperature circuit (60) is
It may be air. Further, the medium temperature fluid of the cooling circuit (70) may be air.

[Brief description of the drawings]

FIG. 1 is a circuit diagram of a refrigeration apparatus showing Embodiment 1 of the present invention.

FIG. 2 is a circuit diagram of a refrigeration apparatus showing Embodiment 2 of the present invention.

FIG. 3 is a circuit diagram of a refrigeration apparatus showing a third embodiment of the present invention.

[Explanation of symbols]

 10 Refrigeration equipment 11 Cogeneration system 20 Refrigeration circuit 21 Evaporator 22 Absorber 23 Generator 24 Condenser 40 Steam turbine (power generator) 50 Auxiliary generator

 ────────────────────────────────────────────────── ─── Continuing on the front page (72) Inventor Kazuo Yonemoto 1304 Kanaokacho, Sakai-shi, Osaka Daikin Industries, Ltd. Sakai Seisakusho Kanaoka Plant F-term (reference) 3G081 BA02 BA12 BB07 BC19 BD00 BD04 DA04 DA07 DA16 3L093 AA01 BB01 BB22

Claims (9)

[Claims] 1. A refrigeration circuit (20) of an absorption refrigeration cycle including a generator (23), a condenser (24), an evaporator (21), and an absorber (22), and the refrigeration circuit (20). A refrigeration system comprising: a power generator (40) that generates power by receiving refrigerant vapor generated by the generator (23) and returns the refrigerant vapor to the absorber (22). 2. The refrigeration circuit (20) according to claim 1, wherein the power generator (40) is connected to the generator (50), while the refrigeration circuit (20) is configured to generate the generator (23) when cold heat is required.
The refrigerant vapor is supplied to the condenser (24) to generate cold heat in the evaporator (21), and when the demand for the cold heat falls below a predetermined amount, a part or all of the refrigerant vapor of the generator (23) is generated as power. A refrigeration device configured to supply the refrigeration equipment (40). 3. The refrigeration circuit (20) according to claim 1, wherein the generator (23) is connected to the condenser (24) and the power generator (40), and the absorber (22) is connected to the evaporator (21). ) And the power generator (40) are provided with branch mechanisms (41, 43), while the branch mechanisms (41, 43) condense the refrigerant vapor of the generator (23) in accordance with the cold load. A refrigeration apparatus characterized in that the refrigerant is configured to flow through the power generator (40) while excess refrigerant vapor flows through the power generator (40). 4. The refrigeration apparatus according to claim 1, further comprising a heat extraction mechanism (70) for extracting at least the heat generated in the absorber (22). 5. The refrigeration apparatus according to claim 1, wherein the heating of the solution in the generator (23) can be performed by using both exhaust heat and combustion heat. 6. The refrigeration apparatus according to claim 1, wherein the refrigeration circuit (20) is configured as a single-effect cycle. 7. The refrigeration apparatus according to claim 1, wherein the refrigeration circuit (20) is configured as a multiple effect cycle. 8. The refrigeration system according to claim 7, wherein the refrigerant vapor of the first generator (23a) is supplied to a power generator (40). 9. The refrigeration system according to claim 7, wherein the refrigerant vapor of the second generator (23b) is supplied to the power generator (40).