JP2004069092A - Absorption type water cooling/heating machine - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To improve energy efficiency of an absorption, type water cooling/heating machine by improving corrosion resistance by preventing stagnation of dew condensation water on a fin. <P>SOLUTION: The absorption type water cooling/heating machine has a heat exchanger for exchanging heat between exhaust gas and solution, a plurality of heat transfer pipes for making the solution flow are arranged horizontally, and the fin on the exhaust side is arranged in the gravity direction. SUS316L or SUS316 is used in the heat transfer pipes, and aluminum material applied with oxide film treatment is used in the fin. Heat is exchanged by counter flow between the solution and the exhaust gas, and the solution is made flow in a cycle in parallel with a high-temperature heat exchanger. <P>COPYRIGHT: (C)2004,JPO

Description

[0001]
TECHNICAL FIELD OF THE INVENTION
The present invention relates to an absorption chiller / heater.
[0002]
[Prior art]
Conventionally, an absorption chiller / heater using, for example, an aqueous solution of lithium bromide as an absorbent and water as a refrigerant is generally known. In the cycle of the absorption refrigerator, in order to regenerate the solution in which the refrigerant has been absorbed, heat is applied to the solution by heating and the refrigerant is evaporated to concentrate the solution. A device that uses a combustion gas from a burner as a heating source and that can also perform a heating operation is called a direct-fired absorption chiller / heater, and is widely used as a heat source device for air conditioning. Also, since the absorption chiller / heater can use various heat sources, it may be driven by high-temperature combustion exhaust gas discharged from the gas turbine as a heat source.
[0003]
In order to increase the energy efficiency of the absorption chiller / heater, a technique of recovering heat from exhaust gas after applying heat in a high-temperature regenerator has been proposed. For example, a technique proposed in Japanese Patent Application Laid-Open No. 6-257891 has been proposed. is there. FIG. 5 shows the configuration. In FIG. 5, the fuel is supplied from the burner 75, the absorbent is concentrated by exchanging heat with the combustion gas and the solution in the high-temperature regenerator 76, and the exhaust gas discharged is guided to the low-temperature regenerator 110. Heat is recovered from exhaust gas by concentration. Further, when the solution is concentrated, the refrigerant vapor evaporates, so that the heat transfer tube 122 is arranged vertically with respect to the ground and the fins 120 in contact with the exhaust gas are arranged horizontally so that the vapor easily escapes to the upper part. .
[0004]
Other means for using the heat recovered from the exhaust gas include means for concentrating the solution in a low-temperature regenerator and means for heating the combustion air as described in JP-A-2000-304370. Has also been proposed.
[0005]
[Problems to be solved by the invention]
In the above-mentioned absorption chiller / heater, the temperature of the combustion exhaust gas is reduced, so that the water vapor in the exhaust gas is liable to be condensed, and when exposed to moisture, there is a problem that the corrosion resistance of the absorption chiller / heater decreases. Since an absorption chiller / heater using water as a refrigerant generally requires a high vacuum state, if a hole is formed due to corrosion, air leaks and the vacuum state is broken. For this reason, even a small hole can be seriously damaged by a machine. In order to prevent dew condensation of the exhaust gas, it is most effective to prevent excessive heat recovery from the combustion exhaust gas and not to lower the temperature of the exhaust gas too much. In general, since fuel contains hydrogen element, water is generated during the combustion, so that the ratio of water vapor in the combustion exhaust gas is higher than that of air, and dew condensation occurs more easily than air. The temperature at which moisture in the exhaust gas condenses varies depending on the type and conditions of the fuel, but is about 50 to 100 ° C. In recovering heat from the exhaust gas, it is possible to control the minimum temperature of the exhaust gas by controlling the temperature and flow rate of the partner to which the heat is applied and the heat transfer capacity of the heat exchanger. For this reason, as far as steady operation is concerned, it is possible to prevent condensation of the exhaust gas while recovering heat from the exhaust gas. However, since the machine is not warm when the absorption chiller / heater is started, the exhaust gas is always exposed to the cold machine, and condensation from the exhaust gas occurs. When the temperature of the exhaust gas rises sufficiently as the machine warms up, it is possible to evaporate the water that has accumulated due to condensation, but is exposed to a corrosive environment until the moisture dries. Therefore, in order to recover heat from combustion exhaust gas in order to increase energy efficiency in the absorption chiller / heater, improvement of corrosion resistance against dew water is the most important issue.
[0006]
Further, when the heat recovered from the exhaust gas is used for concentrating the solution in a low-temperature regenerator, it is necessary to arrange the heat transfer tube in a direction perpendicular to the ground so that the refrigerant vapor can easily escape. In this case, the direction of the fin orthogonal to the heat transfer tube is horizontal. When the fins are oriented in the horizontal direction, when dew condensation water is generated, water tends to stay on the fin surfaces, and there is a problem that the time of exposure to a corrosive environment is prolonged. Therefore, there has been a problem how to utilize the heat recovered from the exhaust gas to increase the energy efficiency of the absorption chiller / heater while taking measures against dew condensation water.
[0007]
Further, since the heat transfer coefficient of a gas is generally considerably lower than that of a liquid, a large heat transfer area is required to sufficiently recover heat from exhaust gas. In the case of exchanging heat between the exhaust gas and the combustion air, the heat exchange between the gases is low because of the heat exchange between the gases, so that a larger heat transfer area is required than in the case of recovering heat with a solution. For this reason, it has also been a problem to configure an exhaust gas heat exchanger having a large heat transfer area with inexpensive materials and means.
[0008]
Therefore, it is an object of the present invention to solve the above-mentioned problems and to realize an absorption chiller / heater provided with an exhaust gas heat exchanger that is less likely to cause corrosion and improved energy efficiency.
[0009]
[Means for Solving the Problems]
In order to achieve the above object, in the present invention, an exhaust gas heat exchanger is provided in parallel with a high-temperature heat exchanger, a plurality of fins of the exhaust gas heat exchanger are oriented in parallel with the direction of gravity, and a heat transfer tube through which the solution flows is set in the direction of gravity. And a configuration arranged in a substantially right angle direction. Furthermore, a plurality of heat transfer tubes through which the solution flows are provided in the flow direction of the exhaust gas, and are connected so that the solution flows continuously from the downstream side to the upstream side in the flow direction of the exhaust gas.
[0010]
BEST MODE FOR CARRYING OUT THE INVENTION
Hereinafter, embodiments of the present invention will be described with reference to an example of an absorption chiller / heater using water as a refrigerant and an aqueous solution of lithium bromide as an absorbent.
[0011]
FIG. 1 is a schematic system diagram of an absorption chiller / heater according to a first embodiment of the present invention, showing circulation in a refrigeration cycle. The absorption chiller / heater using the double effect cycle mainly includes an evaporator 1, an absorber 2, a condenser 3, a low-temperature regenerator 4, a high-temperature regenerator 5, a low-temperature heat exchanger 6, and a high-temperature heat exchanger 7. Elements. A heat transfer tube is arranged in the evaporator 1, cold water flows inside the tube, and refrigerant is sprayed outside the tube. The pressure in the evaporator 1 and the absorber 2 is about 1/100 atm at the same pressure, and the refrigerant evaporates due to the low pressure in the evaporator. The cold water is cooled by removing the latent heat of evaporation from the cold water. This cold water is used as a cold heat source for air conditioning.
[0012]
The refrigerant evaporated by the evaporator is absorbed by the absorber 2. A heat transfer tube is disposed in the absorber 2, and a cooling water flows inside the heat transfer tube, and a solution is sprayed outside the heat transfer tube. The absorption in the absorber 2 proceeds by the cooling water taking away the latent heat of condensation generated when the solution absorbs the refrigerant vapor. The dilute solution whose concentration has been reduced by absorbing the refrigerant is sent to the low-temperature heat exchanger 6 using a circulation pump. The low-temperature heat exchanger 6 exchanges heat between the high-concentration concentrated solution returned from the low-temperature regenerator and the high-temperature regenerator and the dilute solution from the absorber 2. The concentrated solution cooled here is sent to the absorber 2 and used as an absorbing solution. The dilute solution leaving the low-temperature heat exchanger 6 is branched, and one is sent to the low-temperature regenerator 4 and the other is sent to the high-temperature regenerator 5. Branching and circulating the dilute solution in this manner is called parallel float. The low-temperature regenerator 4 is provided with a heat transfer tube. The refrigerant vapor generated in the high-temperature regenerator 5 flows inside the heat transfer tube, and the dilute solution from the low-temperature heat exchanger 6 is sprayed outside the heat transfer tube. The dilute solution sent to the low-temperature regenerator 4 is heated on the heat transfer tube to generate refrigerant vapor, and the refrigerant vapor inside the heat transfer tube is condensed by applying heat to the solution. The solution concentrated in the low-temperature regenerator 4 is combined with the solution concentrated in the high-temperature regenerator 5 and sent to the low-temperature heat exchanger 6. The refrigerant vapor generated from the solution in the low-temperature regenerator 4 and the refrigerant condensed in the tubes of the low-temperature regenerator 4 are sent to the condenser 3. The condenser 3 is provided with a heat transfer tube, in which cooling water flows inside the tube, cools the refrigerant vapor outside the tube, and condenses the refrigerant vapor. The liquid refrigerant generated in the condenser 3 is sent to the evaporator 1.
[0013]
The dilute solution leaving the low-temperature heat exchanger 6 is branched to the low-temperature regenerator 4 and the high-temperature regenerator 5. The dilute solution sent to the high-temperature regenerator 5 is further branched, and one is sent to the high-temperature heat exchanger 7 and the other is sent to the exhaust gas heat exchanger 9. In the high-temperature heat exchanger 7, heat is exchanged between the concentrated solution returned from the high-temperature regenerator 5 and the dilute solution from the low-temperature heat exchanger 6. In the exhaust gas heat exchanger 9, heat is exchanged between the exhaust gas discharged from the high-temperature regenerator 5 and the dilute solution from the low-temperature heat exchanger 6. The dilute solutions exiting the high-temperature heat exchanger 7 and the exhaust gas heat exchanger 9 are combined again and sent to the high-temperature regenerator 5. In the high-temperature regenerator 5, the solution is heated and boiled by the combustion gas generated in the burner 8, and the solution is concentrated. As a heat source of the high-temperature regenerator 5, a high-temperature exhaust gas from a gas turbine or the like can be used in addition to the combustion gas from the burner 8. In the absorption chiller / heater, the fuel consumed by the burner 8 is the main energy consumption. Therefore, reducing the energy input to the high-temperature regenerator 5 increases the energy efficiency. The exhaust gas heat exchanger 9 heats the dilute solution, thereby increasing the temperature of the solution flowing into the high-temperature regenerator 5 and reducing the energy consumed for heating the solution in the high-temperature regenerator 5.
[0014]
Since the concentrated solution that exchanges heat in the high-temperature heat exchanger 7 is a return solution from the high-temperature regenerator 5, the flow rate of the concentrated solution is smaller than that of the solution flowing into the high-temperature regenerator 5 by the amount of the refrigerant evaporated in the high-temperature regenerator 5. Therefore, when the exhaust gas heat exchanger 9 is not used, the flow rate of the solution to be heat-exchanged in the high-temperature heat exchanger 7 is always smaller in the concentrated solution than in the dilute solution. In this case, even if the concentrated solution and the dilute solution perform heat exchange from the relation of heat capacity, the temperature of the dilute solution does not increase as the temperature of the concentrated solution decreases. Therefore, no matter how much the heat transfer area of the high-temperature heat exchanger 7 is increased, there is a limit in bringing the outlet temperature of the dilute solution closer to the inlet temperature of the concentrated solution. When the exhaust gas heat exchanger 9 for flowing the dilute solution in parallel with the high-temperature heat exchanger 7 is arranged, the flow rate of the dilute solution flowing to the high-temperature heat exchanger 7 is smaller than when the dilute solution is flown for the high-temperature heat exchanger 7 alone. Decrease. For this reason, the difference between the outlet temperature of the dilute solution and the inlet temperature of the concentrated solution of the high-temperature heat exchanger 7 is reduced (the above-mentioned limit is eliminated), and it is also useful to increase the outlet temperature of the dilute solution in the high-temperature heat exchanger 7. . As a method of flowing the dilute solution to the exhaust gas heat exchanger 9, a method of arranging the high-temperature heat exchanger 7 and the exhaust gas heat exchanger 9 in series and flowing the entire amount of the dilute solution has been proposed. However, in order to sufficiently recover heat from the exhaust gas and increase the temperature of the dilute solution flowing into the high-temperature regenerator 5, the exhaust gas heat exchanger 9 and the high-temperature heat exchanger 7 are arranged in parallel, and the dilute solution is removed. The configuration in which the heat is branched and flown to each of the heat exchangers can increase the energy efficiency as compared with the case where they are arranged in series.
[0015]
When the parallel flow is used, the circulating dilute solution (the dilute solution leaving the low-temperature heat exchanger 6) is branched into the low-temperature regenerator 4 and the high-temperature regenerator 5 (high-temperature heat exchanger 7). Therefore, the amount of the solution flowing through the high-temperature heat exchanger 7 is reduced to half the amount of the solution flowing through the low-temperature heat exchanger 6. Accordingly, since the amount of the dilute solution flowing through the high-temperature heat exchanger 7 is small, the difference between the outlet temperature of the dilute solution and the inlet temperature of the concentrated solution of the high-temperature heat exchanger 7 becomes small. Therefore, there is a feature that the temperature efficiency in the high-temperature heat exchanger 7 can be easily improved. However, when the exhaust gas heat exchanger 9 is not provided in parallel, there is a limit to increasing the temperature of the dilute solution exiting the high-temperature heat exchanger 7 as described above. By arranging the high-temperature heat exchanger 7 and the exhaust gas heat exchanger 9 in parallel, the amount of the dilute solution flowing through the high-temperature heat exchanger 7 is further reduced. For this reason, the temperature of the dilute solution on the outlet side of the high-temperature heat exchanger 7 can be increased, and the limit can be increased. As described above, in the parallel flow absorption chiller / heater, the configuration in which the high temperature heat exchanger 7 and the exhaust gas heat exchanger 9 are arranged in parallel can maximize the energy efficiency.
[0016]
When the absorption chiller / heater is used in the heating operation by the heating cycle, the circulation of the solution is the same as that in FIG. 1, so that the exhaust gas heat exchanger 9 works effectively and the energy efficiency can be increased.
[0017]
FIG. 2 is a diagram illustrating a basic configuration of an exhaust gas heat exchanger used in the present invention. The exhaust gas 10 and the dilute solution 11 discharged from the high temperature regenerator 6 exchange heat through the heat transfer tubes 12 and the fins 13. Although the case where the exhaust gas 10 flows in a direction perpendicular to the direction of gravity (horizontal) is shown here as an example, the same configuration can be applied to the case where the exhaust gas flows in the direction of gravity (perpendicular to the ground). By adopting a fin-and-tube method as the form of the heat exchanger, the heat transfer area on the exhaust gas side with a poor heat transfer rate is increased, and the heat transfer area on the dilute solution side with a good heat transfer rate is reduced. You can use the heat area.
[0018]
The fins 13 in contact with the exhaust gas are arranged parallel to the flow of the exhaust gas 10 and at the same time in the direction of gravity (perpendicular to the ground). Thus, the heat transfer tubes 12 orthogonal to the fins 13 are necessarily arranged horizontally (at right angles to the direction of gravity). Since the fins 13 are arranged in the direction of gravity, even if dew condensation occurs temporarily from the exhaust gas and water is attached to the fins 13, the water flows down, and the fins 13 and the heat transfer tubes 12 may be exposed to the corrosive environment for a long time. Disappears. That is, anti-corrosion measures are taken by arranging the fins 13 in parallel with the direction of gravity. The reason why no problem occurs when the heat transfer tube 12 is horizontal is that the solution is not boiled. This is because boiling was not caused. In particular, by making the exhaust gas heat exchanger 9 flow the solution in parallel with the high-temperature heat exchanger 7, the temperature difference between the inlet and the outlet of the exhaust gas heat exchanger 9 was increased. This is made possible by allowing sufficient heat recovery by sensible heat. A plurality of heat transfer tubes 12 are present in contact with the fins 13 at the straight portions, but are connected in a U-shape at both ends to allow the dilute solution 11 to flow from the downstream side of the exhaust gas 10, From the exhaust gas 10 and the flow of the exhaust gas 10 and the flow of the dilute solution 11 become countercurrent. In this way, the temperature of the dilute solution on the outlet side of the exhaust gas heat exchanger 9 can be raised to the exhaust gas inlet side temperature by using the counter flow method, and the difference between the inlet side temperature and the outlet side temperature can be increased, thereby improving the temperature efficiency. it can.
[0019]
In the present invention, the exhaust gas heat exchanger 9 used exchanges sensible heat with both the exhaust gas 10 and the dilute solution 11, so that the effect of using the counter flow in which the temperature efficiency can be maximized is great. When the temperature efficiency increases, the outlet temperature of the dilute solution 11 increases, so that a small amount of the dilute solution 11 can sufficiently recover heat from the exhaust gas 10 and the heat transfer area does not need to be increased. The fact that only a small amount of the dilute solution 11 needs to flow is an advantage of disposing the exhaust gas heat exchanger 9 in parallel with the high-temperature heat exchanger 7. If too much dilute solution 11 flows into the exhaust gas heat exchanger 9, the amount of heat that can be recovered by the high-temperature heat exchanger 7 decreases, and the energy efficiency of the absorption chiller / heater does not improve. By flowing a smaller amount of the dilute solution 11 to the exhaust gas heat exchanger 9 than the amount to be passed to the vessel 7, the energy efficiency of the absorption chiller / heater is sufficiently improved. As described above, the method of limiting the flow rate flowing to the exhaust gas heat exchanger 9 can be realized by a method of designing the flow path resistance of the exhaust gas heat exchanger 9 to be large, a method of providing an orifice, or the like. .
[0020]
It is preferable to use SUS316L or SUS316 as the material of the heat transfer tube 12 in FIG. 2, and it is preferable to use an aluminum material subjected to an oxide film treatment for the fins 13. The outside of the heat transfer tube 12 in the exhaust gas heat exchanger 9 is exposed to a corrosive environment due to dew condensation water caused by the exhaust gas 10, and the inside is exposed to a corrosive environment due to a solution. Generally, since the aqueous solution of lithium bromide used in the solution has a strong corrosive property, the exhaust gas heat exchanger 9 in the absorption chiller / heater is subjected to a more severe corrosive environment. For this reason, it is conceivable to use a stainless steel material excellent in corrosion resistance as the material of the heat transfer tube 12. However, since it is important for the absorption chiller / heater to ensure airtightness, it is necessary to secure complete airtightness by welding when connecting the heat transfer tubes 12. For this reason, it has been devised to use a stainless steel material for the heat transfer tube 12 and to use an austenitic stainless steel. However, on the other hand, austenitic stainless steel has a risk of causing stress corrosion cracking. Stress corrosion cracking is likely to occur when exposed to corrosive liquids, in a restricted environment, or when exposed to a high temperature environment, and the heat transfer tube 12 of the exhaust gas heat exchanger 9 also satisfies this condition.
[0021]
As a result of testing various materials based on these conditions, it was found that it is safest to use SUS316L or SUS316 for the heat transfer tube 12 in the exhaust gas heat exchanger 9. It is most important to use inexpensive materials for the fins 13 because they require a large heat transfer area, but on the other hand, because they are exposed to the corrosive environment from the condensed water of the exhaust gas, they also need to improve the corrosion resistance. . For this reason, it has been concluded that it is most efficient to use an aluminum material for the fins 13 and to perform a treatment for forming an oxide film on the surface.
[0022]
FIG. 3 is a diagram illustrating a practical configuration of the exhaust gas heat exchanger used in the present invention. A plurality of the fin-and-tube units shown in FIG. 2 are stacked in a direction perpendicular to the flow direction of the exhaust gas 10, and the entrance and exit of the heat transfer tube 12 of each unit are connected to the header 14. Thereby, the dilute solution 11 is distributed by the header 14, and the distributed solution flows in each unit so as to face the exhaust gas. Although the structure shown in FIG. 2 can be used as a heat exchanger, the cross-sectional area of the exhaust gas can be increased, and the exhaust gas 10 and the dilute solution 11 can be opposed to each other to achieve a temperature as a heat exchanger. The advantage of the structure of FIG. 2 in increasing the efficiency is not lost. In this way, by adopting a configuration in which unitized exhaust gas heat exchangers are stacked in multiple stages, the configuration can be easily changed according to the capacity (flow rate of exhaust gas) required by the heat exchanger.
[0023]
FIG. 4 is a schematic system diagram of an absorption chiller / heater according to a second embodiment of the present invention. The difference from FIG. 1 is that a drain heat exchanger 15 is provided in parallel with the low-temperature heat exchanger 6. That is, the dilute solution leaving the absorber 2 is branched before flowing into the low-temperature heat exchanger 6, one of which flows into the low-temperature heat exchanger 6 as usual, and the other flows into the drain heat exchanger 15. The dilute solution exiting the drain heat exchanger 15 is combined with the dilute solution exiting the low-temperature heat exchanger 6, so that the drain heat exchanger 15 is arranged in parallel with the low-temperature heat exchanger 6. A liquid refrigerant coming out of the low-temperature regenerator 4 is applied to the other fluid for heat exchange in the drain heat exchanger 15. This liquid refrigerant is condensed from the vapor by applying heat to the solution in the low-temperature regenerator 4, and is sent to the condenser 3 after leaving the drain heat exchanger 15. Since there is a temperature difference between the temperature of the condenser 3 and the temperature of the low-temperature regenerator 4, heat can be recovered.
[0024]
On the other hand, there is a difference in flow rate between the dilute solution and the concentrated solution that exchange heat in the low-temperature heat exchanger 6 as in the case of the high-temperature heat exchanger 7. That is, without the drain heat exchanger 15, the flow rate of the concentrated solution is always smaller than that of the dilute solution. Therefore, no matter how much the heat transfer area of the low-temperature heat exchanger 6 is increased, there is a limit in bringing the outlet temperature of the dilute solution closer to the inlet temperature of the concentrated solution. Therefore, similarly to the relationship between the high-temperature heat exchanger 7 and the exhaust gas heat exchanger 9, the temperature of the dilute solution can be increased by disposing the low-temperature heat exchanger 6 and the drain heat exchanger 15 in parallel. It is possible to further increase the energy efficiency as compared to the embodiment.
[0025]
【The invention's effect】
As described above, according to the present invention, by providing an exhaust gas heat exchanger that contacts exhaust gas with fins arranged in the direction of gravity and exchanges heat with the solution, the dew condensation water of the exhaust gas is dropped from the fin. In addition, heat recovery from exhaust gas can be performed after improving corrosion resistance against dew condensation water, and it becomes possible to improve the energy efficiency of the absorption chiller / heater. Further, by realizing the heat exchange by the counter flow of the exhaust gas and the solution, the temperature efficiency of the exhaust gas heat exchanger can be increased, and the energy efficiency of the absorption chiller / heater can be improved. In addition, by stacking fin-and-tube units that exchange heat between the exhaust gas and the solution in the counterflow, and configuring the exhaust gas heat exchanger, the heat in accordance with the flow rate of the exhaust gas can be maintained while maintaining the advantages of the counterflow. It becomes possible to manufacture an exchanger. Further, by using SUS316L or SUS316 for the heat transfer tube of the exhaust gas heat exchanger and using an aluminum material whose oxide fin has been treated for the fins, it is possible to suppress an increase in cost and improve corrosion resistance. Further, as the solution circulation method in the absorption chiller / heater, by arranging the exhaust gas heat exchanger in parallel with the high temperature heat exchanger in a parallel flow, higher energy efficiency can be realized. Further, by arranging the drain heat exchanger in parallel with the low-temperature heat exchanger, it is possible to improve the energy efficiency in addition to the effect of the exhaust gas heat exchanger.
[Brief description of the drawings]
FIG. 1 is a schematic system diagram of an absorption chiller / heater according to a first embodiment of the present invention.
FIG. 2 is a diagram showing a basic configuration of an exhaust gas heat exchanger used in the present invention.
FIG. 3 is a diagram showing a configuration of an exhaust gas heat exchanger used in the present invention.
FIG. 4 is a schematic system diagram of an absorption chiller / heater according to a second embodiment of the present invention.
FIG. 5 is a diagram showing an example of a technique for recovering heat from exhaust gas in an absorption chiller / heater.
[Explanation of symbols]
DESCRIPTION OF SYMBOLS 1 ... Evaporator, 2 ... Absorber, 3 ... Condenser, 4 ... Low temperature regenerator, 5 ... High temperature regenerator, 6 ... Low temperature heat exchanger, 7 ... High temperature heat exchanger, 9 ... Exhaust gas heat exchanger, 12 ... Heat transfer tubes, 13 fins, 15 drain heat exchangers.

Claims (8)

Equipped with an evaporator, condenser, low-temperature regenerator, high-temperature regenerator, low-temperature heat exchanger, and high-temperature heat exchanger.The absorption refrigeration cycle is configured by circulating the solution, and the high-temperature regenerator is heated with combustion gas. In the water machine,
An exhaust gas heat exchanger that exchanges heat between the exhaust gas and the solution that has exited the high-temperature regenerator is provided.In the exhaust gas heat exchanger, fins that are in contact with the exhaust gas are arranged in the direction of gravity, and a heat transfer tube that flows the solution is substantially perpendicular to the direction of gravity. An absorption chiller-heater characterized by being arranged. The absorption chiller / heater according to claim 1,
A plurality of heat transfer tubes of the exhaust gas heat exchanger are arranged in the flow direction of the exhaust gas, and the plurality of heat transfer tubes are connected so that the solution flows continuously. An absorption chiller / heater characterized by flowing water and flowing out a solution from a heat transfer tube on the upstream side of exhaust gas. The absorption chiller / heater according to claim 2,
As a unit, a heat transfer tube connected to the exhaust gas flow direction and a fin in contact with the exhaust gas are arranged as a unit, a plurality of the units are arranged in a direction perpendicular to the flow direction of the exhaust gas, and the heat transfer tubes are distributed so that the solution is distributed to each unit and flows. An absorption chiller / heater characterized by being connected. The absorption chiller / heater according to claim 1,
The heat transfer tube of the exhaust gas heat exchanger is made of SUS316L or SUS316, and the fin is made of an aluminum material having an oxide film treated. Equipped with an evaporator, condenser, low-temperature regenerator, high-temperature regenerator, low-temperature heat exchanger, and high-temperature heat exchanger.The absorption refrigeration cycle is configured by circulating the solution, and the high-temperature regenerator is heated with combustion gas. In the water machine,
The dilute solution leaving the absorber flows into a low-temperature heat exchanger, the dilute solution leaving the low-temperature heat exchanger branches, one flows into a low-temperature regenerator, the other further branches, and one of the high-temperature heat Flowing into the heat exchanger and the other into the exhaust gas heat exchanger, and combining the dilute solutions from the high-temperature heat exchanger and the exhaust gas heat exchanger into a high-temperature regenerator. Hot and cold water machine. The absorption chiller / heater according to claim 5,
An exhaust gas heat exchanger for exchanging heat between the exhaust gas and the solution that has exited the high-temperature regenerator is provided.The exhaust gas heat exchanger includes fins that are in contact with the exhaust gas in the direction of gravity, and heat transfer tubes through which the solution flows are substantially perpendicular to the direction of gravity. An absorption chiller / heater, wherein: The absorption chiller / heater according to claim 6,
A plurality of heat transfer tubes of the exhaust gas heat exchanger are arranged in the flow direction of the exhaust gas, and the plurality of heat transfer tubes are connected so that the solution flows continuously. An absorption chiller / heater characterized by flowing water and flowing out a solution from a heat transfer tube on the upstream side of exhaust gas. The absorption chiller / heater according to claim 5,
The dilute solution exiting the absorber is branched, one is passed to a low-temperature heat exchanger, and the other is passed to a drain heat exchanger that exchanges heat with the refrigerant exiting the low-temperature regenerator, and the low-temperature heat exchanger and the drain are drained. An absorption chiller / heater, wherein the dilute solution discharged from the heat exchanger is combined.

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