JPH04169764A - Absorption heat pump - Google Patents

Abstract

PURPOSE:To avoid crystalization of absorption liquid and enable a stable extraction of non-condensed gas to be attained by a method wherein an absorption liquid heat exchanger for heat exchanging an absorption liquid from an absorption liquid pump with refrigerant liquid from a refrigerant heat exchanger is provided in the midway part of a refrigerant pipe extending from a condensor to an evaporator. CONSTITUTION:An ejector 26 and a condensor 3 are connected by an extraction pipe 24. A rich liquid pipe 13 at a discharging side of an absorption liquid pump 8 and the ejector 26 are connected by a rich liquid feeding pipe 27. An absorption liquid heat exchanger 28 is installed in the midway part of the feeding pipe 27. Concentrated liquid flowing through the feeding pipe 27 and refrigerant liquid flowing out of a refrigerant heat exchanger 22A are introduced to a heat exchanger 28, and then the concentrated liquid, which has been cooled, is sent to the ejector 26. With such an arrangement, the refrigerant liquid sent from the condensor 3 to the evaporator 6 is heated at the refrigerant heat exchanger 22A, and further heated at the absorption liquid heat exchanger, and the liquid flows into the evaporator 6, so that the temperature of the evaporator 6 can be further increased and stabilized.

Description

DETAILED DESCRIPTION OF THE INVENTION (a) Industrial Application Field The present invention relates to an absorption heat pump that extracts hot water at a higher temperature than a supplied heat source fluid.

(b) Conventional technology For example, Japanese Patent Application Laid-open No. 60-221671 discloses an air extraction device that extracts non-condensable gas from the condenser using a part of the concentrated absorption liquid inside the device. An absorption heat pump is disclosed in which a heat exchanger is provided in the middle of a refrigerant flow path from the condenser to the evaporator to raise the temperature of the refrigerant liquid flowing out from the condenser by the concentrated absorption liquid flowing into the evaporator.

(C) Problems to be Solved by the Invention In the above-mentioned conventional technology, when the temperature of the cooling water is low, for example in winter, the temperature of the refrigerant liquid flowing out from the condenser also decreases. When the temperature of the refrigerant liquid decreases, the temperature of the concentrated absorption liquid at the outlet of the heat exchanger decreases, and if the temperature further decreases in the bleeder, there is a risk that crystals will occur in the bleeder.

SUMMARY OF THE INVENTION An object of the present invention is to provide an absorption heat pump that avoids crystallization of an absorption liquid in an extraction device and stably extracts non-condensable gas.

(2) Means for Solving the Problems In order to solve the above problems, the present invention connects an evaporator (6), an absorber (5), a generator (2), and a condenser (3) with piping to Absorption liquid piping (concentrated liquid piping) (13) that connects the generator (2) to the absorber (5) and has an absorption liquid pump (8) along the way, forming a circulation path for the absorption liquid and the absorption liquid. It is equipped with an extraction device (23) that extracts non-condensable gas inside the machine using the absorption liquid flowing out from the pump (8), supplies heat source fluid to the evaporator (6) and the generator (2), and supplies the heat source fluid to the condenser ( In an absorption heat pump, cooling water flows through the condenser (3) and a heated fluid having a higher temperature than the heat source fluid is extracted from the absorber (5).
A refrigerant heat exchanger (22A) installed in the refrigerant liquid pipe (11) leading from the condenser (3) to the evaporator (6) and exchanging heat between the refrigerant liquid from the condenser (3) and the heat source fluid from the evaporator (6). The absorption liquid from the absorption liquid pump (8) and the refrigerant heat exchanger are provided in the absorption liquid piping (absorption liquid feeding piping) 27) from the outlet side of the absorption liquid pump (8) to the extraction device (23). (22A)
The absorption liquid heat exchanger (28) is equipped with an absorption liquid heat exchanger (28) in which the refrigerant liquid from It provides heat pumps.

Furthermore, a refrigerant heat exchanger (22A) that exchanges heat between the refrigerant liquid sent from the condenser (3) to the evaporator (6) and the heat source fluid flowing out from the evaporator (6) or the generator (2); The extraction device includes an absorption liquid heat exchanger (28) that exchanges heat between the absorption liquid flowing out from the liquid pump (8) and sent to the extraction device (23) and the refrigerant liquid flowing out from the refrigerant heat exchanger (22A). (2
3) To provide an absorption heat pump that prevents the temperature of the absorption liquid sent to the absorbent from significantly lowering and prevents the generation of crystals in the extraction device (23).

(*) The refrigerant liquid whose temperature has increased by exchanging heat with the heat source fluid from the evaporator (6) in the working refrigerant heat exchanger (22A>) is transferred to the absorption liquid heat exchanger (
28). Then, in the absorption liquid heat exchanger (28), the refrigerant liquid from the refrigerant heat exchanger (22A) and the absorption liquid for air extraction exchange heat, so the temperature of the absorption liquid increases significantly in the absorption liquid heat exchanger (28). It is possible to avoid crystallization of the absorption liquid sent from the absorption liquid heat exchanger (28) to the extraction device (23), and it is possible to stably operate the extraction device (23). become.

Also, it flows out from the condenser (3) and flows into the refrigerant heat exchanger (22A>
The refrigerant liquid whose temperature has increased at The absorption liquid for air extraction is cooled in the absorption liquid heat exchanger (28) by the refrigerant liquid whose temperature has risen, so the absorption liquid heat exchanger (28) can prevent the temperature of the absorption liquid from dropping significantly, and Device (2
3) It is possible to avoid crystallization of the absorption liquid sent to
It becomes possible to operate the extraction device (23) stably.

(F) Example Hereinafter, an example of the present invention will be described in detail based on the drawings.

FIG. 1 shows a first embodiment of the present invention, and is a circuit diagram of an absorption refrigerator using an aqueous solution of lithium bromide (LiBr>) as an absorption liquid and water as a refrigerant.

In Figure 1, (1) is a generator (2) and a condenser (3).
), (4) houses the absorber (5) and evaporator (
6) is the upper body that houses it. In addition, (7) is a solution heat exchanger, (8) is an absorption liquid pump, (9) is a refrigerant pump, and (1o
) is a refrigerant circulation pump. These devices include a refrigerant liquid pipe (11), a refrigerant liquid circulation pipe (12), a concentrated liquid pipe (13) through which an absorption liquid (hereinafter referred to as concentrated liquid) in which the refrigerant has been separated and whose concentration has become high flows, and a refrigerant liquid circulation pipe (12). Replenishment pipe (14) through which the absorbed liquid (hereinafter referred to as glaze liquid) whose concentration has become lower due to absorption flows
The connection is made airtight. A circulation path for refrigerant and absorption liquid similar to that of a conventional absorption heat pump of this type (for example, see the absorption heat pump device described in Japanese Patent Application Laid-open No. 58-138961) is configured.

(15) is the heater of the generator (2), (16) is the condenser (
3) is the cooler, (17) is the heated device of the absorber (5), (
18) is a heater for the evaporator (6). (19) is the heat source supply pipe connected to the heater (15), (20) is the cooling water pipe connected to the cooler (16), and (21) is the heated device (
(22) is a heat source supply pipe connected to the heater (18). and,
A heat source fluid such as waste hot water or waste steam flows through the heat source supply pipes (19) and (22) as indicated by the arrows. (2
2A) is the heat source supply pipe (22) on the outlet side of the evaporator 6)
This heat exchanger (22A) exchanges heat between the refrigerant liquid from the condenser (3) and the heat source fluid from the evaporator (6), and the temperature of the refrigerant liquid changes. will rise.

(23) is an air extraction device connected to the gas phase part of the condenser (3) by an air extraction pipe (24).This air extraction device (23)
consists of a non-condensable gas tank (25) and an ejector (26) provided above the non-condensable gas tank. Further, the non-condensable gas tank (25) is composed of an upper non-condensable gas storage chamber (25A) and a lower separation chamber (27). Then, the ejector (26) and the condenser (
3) are connected by the air bleed pipe (24).

Further, the concentrated liquid pipe (13) on the discharge side of the absorption liquid pump (8) and the ejector (26) are connected by a concentrated liquid feed pipe (27). An absorption liquid heat exchanger (28) is provided in the middle of the feed pipe (27), and this heat exchanger (28
), the concentrated liquid flowing through the feed pipe (27) and the refrigerant liquid flowing out from the refrigerant heat exchanger (22A) exchange heat, and the concentrated liquid whose temperature has decreased is sent to the ejector (26). (3
0) is a non-condensable gas discharge pipe connected to the upper part of the non-condensable gas tank (25), (31) is an on-off valve, and (32)
) is a bleed pump. Then, when the non-condensing pressure in the storage chamber (25A) becomes high or periodically, the on-off valve (3
1) and operate the extraction pump (32) to discharge the non-condensable gas to the outside.

When the absorption heat pump configured as described above is operated, high-temperature water (heat source fluid) of, for example, 98°C flows from equipment such as a chemical plant or factory to the heater (18) of the evaporator (6). , heat is radiated by a heater (18). Then, high-temperature water of, for example, 88°C, whose temperature has been lowered in the heater (18), flows from the heater (18) to the refrigerant heat exchanger (22A). For example, the sent refrigerant liquid at 35°C is passed through the refrigerant heat exchanger (2
2A), the temperature rises, and the refrigerant liquid at, for example, 65°C flows out from the refrigerant heat exchanger (22A). Further, heat is radiated in the refrigerant heat exchanger (22A), and high-temperature water whose temperature has decreased to, for example, 80° C. flows out from the refrigerant heat exchanger (22A).

A part of the concentrated liquid at, for example, 83°C discharged from the absorption liquid pump (8) passes through the feed pipe (27) to the absorption liquid heat exchanger (28).
). In the absorption liquid heat exchanger (28), 83°C
The concentrated liquid and the chilled liquid at 65°C exchange heat, and the concentrated liquid whose temperature has decreased to, for example, 70°C is sent to the ejector (26). Further, the refrigerant liquid whose temperature has increased to, for example, 75°C is sent to the evaporator (6>).Then, the non-condensable gas in the condenser (3) is extracted by the concentrated liquid ejected by the ejector (26). Here, the temperature in the non-condensable gas tank (25) becomes approximately 70'C, and the saturated vapor pressure becomes 20 mlHg.Then, the pressure in the non-condensable gas tank (25) becomes equal to the pressure in the condenser (3), for example, 411 !21aHg than nHg
The non-condensable gas is extracted through the bleed pipe (24). Furthermore, even when the temperature of the cooling water flowing through the condenser (3) decreases, the concentrated liquid sent to the extraction device (23) exchanges heat with the refrigerant liquid whose temperature has increased in the refrigerant heat exchanger (22A). , the temperature of the concentrated liquid does not drop significantly.

According to the above embodiment, the concentrated liquid for extraction flowing into the absorption liquid heat exchanger (28) is cooled by the refrigerant liquid whose temperature has risen due to heating by the heat source fluid in the refrigerant heat exchanger (22A). Ru. For this reason, for example, due to seasonal changes,
Even if the temperature of the cooling water decreases and the temperature of the refrigerant liquid flowing out from the condenser (3) decreases, the temperature of the concentrated liquid sent to the extraction device (23) can be prevented from dropping significantly, and the extraction Crystallization of the concentrated liquid in the device (23) can be avoided. Furthermore, since the absorption liquid whose temperature has been lowered in the absorption liquid heat exchanger (28) is sent to the extraction device (23), the ability of the concentrated liquid to absorb non-condensable gas is increased and the extraction capacity can be improved.

In addition, the temperature of the refrigerant liquid sent from the condenser (3) to the evaporator (6) increases in the refrigerant heat exchanger (22A), and further increases in temperature in the absorption liquid heat exchanger (28), and then passes through the evaporator. (6), the temperature of the evaporator (6) can be raised to an extremely high temperature, and the temperature of the evaporator (6) can be stabilized. As a result, the temperature of the absorber (5) can be increased. Forgive me for stability,
The temperature of hot water taken out from the absorber (5) can be stabilized.

Furthermore, as shown by the broken line in FIG. 1, when a refrigerant heat exchanger (22A) is provided in the heat source supply pipe (19) on the outlet side of the generator (2) and the refrigerant liquid is heated with the heat source fluid, A nine-pronged evaporator (6
) and the heat source fluid from the generator (2) are allowed to merge, and the same effect can be obtained when the combined heat source fluid heats the refrigerant liquid from the condenser (3). .

FIG. 2 is a circuit configuration diagram of an absorption heat pump showing a second embodiment of the present invention. In FIG. 2, the same components as in FIG. Explanation will be omitted.

In FIG. 2, a side pipe (IIA) is connected to the refrigerant liquid pipe (11) on the outlet side of the refrigerant heat exchanger (22A), and an absorption liquid heat exchanger (28 ) is provided. Further, (40) is a flow rate control valve provided in the refrigerant liquid pipe (11). When the absorption refrigerator is in operation, a part of the refrigerant liquid whose temperature has increased in the refrigerant heat exchanger (22A) is flowed to the absorption liquid heat exchanger (28). The temperature is adjusted, for example, based on the temperature of the concentrated liquid flowing out from the absorption liquid heat exchanger (28), and the amount of refrigerant liquid flowing into the absorption liquid heat exchanger (28) is adjusted.

Therefore, the temperature of the concentrated liquid sent to the bleeder (23) can be further stabilized (crystallization in the bleeder (23) can be avoided).

Furthermore, FIG. 3 is a circuit configuration diagram of an absorption heat pump showing a third embodiment of the present invention. In FIG. 3, the same components as in FIG. Detailed explanation will be omitted.

In FIG. 3, (41) is a bypass pipe that bypasses the refrigerant heat exchanger (22A), and the absorption liquid heat exchanger (28) is provided in this bypass pipe (41). Further, (42> is a connecting pipe that connects the refrigerant liquid pipe (11) on the outlet side of the refrigerant heat exchanger (22A) and the side pipe (41) on the inlet side of the absorption liquid heat exchanger (28), ( 43) and (44) are flow control valves provided in the refrigerant liquid pipe (11) and the side pipe (41), respectively.When the absorption heat pump is operating, the refrigerant liquid flows as shown by the solid line arrow. , 35°C refrigerant liquid flowing through the side pipe (41) via the flow rate control valve (44),
The refrigerant liquid flowing through the communication pipe (42) at, for example, 65°C is mixed, and the refrigerant liquid at about 50°C, which is lower than that in the first and second embodiments, is transferred to the absorption liquid heat exchanger (28). ).

Here, the opening degree of the flow rate control valve (44) is large when the temperature of the cooling water is high in the summer and the temperature of the refrigerant liquid from the condenser (3) is high, and it is large in the winter when the temperature of the cooling water is low and the temperature of the refrigerant liquid from the condenser (3) is high.
When the temperature of the refrigerant liquid from 3) is low, it is manually adjusted.

In the third embodiment described above, the refrigerant liquid that has passed through the refrigerant heat exchanger (22A) and the refrigerant liquid that has flowed through the side pipe (41) are mixed, and the refrigerant liquid at about 50° C. undergoes heat exchange with the absorption liquid. Flows into the vessel (28). Therefore, the temperature of the concentrated liquid flowing out from the absorption liquid heat exchanger (28) is further reduced, and the extraction capacity of the extraction device (23) can be further improved.

(G) Effects of the Invention The present invention is an absorption heat pump configured as described above, which is installed in the refrigerant pipe leading from the condenser to the evaporator and exchanges heat between the refrigerant liquid from the condenser and the heat source fluid from the evaporator. A refrigerant heat exchanger that exchanges heat between the absorption liquid sent to the device, which is installed in the absorption liquid piping leading from the absorption liquid pump to the extraction device, and the refrigerant liquid flowing out from the refrigerant heat exchanger. The temperature of the refrigerant liquid is raised by the refrigerant heat exchanger, and the absorption liquid is cooled by this refrigerant liquid by the absorption liquid heat exchanger, and the temperature is lowered and sent to the extraction device, so that the cooling water is Even when the temperature of the absorption liquid decreases, the temperature of the absorption liquid sent to the extraction device can be prevented from dropping significantly, and the temperature of the absorption liquid can be stabilized. As a result, the crystallization of the absorption liquid in the extraction device can be prevented. This allows stable operation of the extraction device. Further, since the absorption liquid discharged from the absorption liquid pump and whose temperature has been lowered by the absorption liquid heat exchanger is sent to the extraction device, the extraction capacity of the extraction device can be improved.

In addition, there is a refrigerant heat exchanger that exchanges heat between the refrigerant liquid sent from the condenser to the evaporator and the heat source fluid flowing out from the evaporator or generator, and the absorption liquid and refrigerant flowing out from the absorption liquid pump and sent to the extraction device. An absorption liquid heat exchanger that exchanges heat with the refrigerant liquid from the heat exchanger, the refrigerant heat exchanger heats the refrigerant liquid with the heat source fluid from the evaporator or generator to raise the temperature, Since the absorption liquid is cooled in the absorption liquid heat exchanger and sent to the extraction device, it is possible to prevent the temperature of the absorption liquid flowing to the extraction device from dropping significantly, to avoid crystallization of the absorption liquid in the extraction device, and to The device can be operated stably.

[Brief explanation of the drawing]

FIG. 1 is a circuit diagram of an absorption heat pump according to a first embodiment of the present invention, FIG. 2 is a circuit diagram of an absorption heat pump according to a second embodiment of the present invention, and FIG. 3 is a circuit diagram of an absorption heat pump according to a second embodiment of the present invention. FIG. 3 is a circuit configuration diagram of an absorption heat pump showing a third embodiment. (2)...generator, (3)...condenser, (5)
...Absorber, (6)...Evaporator, (8)...
Absorption liquid pump, (11)... Refrigerant liquid piping, <13
〉... Concentrated liquid piping, (19), (22)... Heat source supply piping, (22A)... Refrigerant heat exchanger, (23
)...Air extraction device, (27)...Concentrated liquid feed piping,
(28)...Absorption liquid heat exchanger.

Claims (1)

[Claims] 1. The evaporator, absorber, generator, and condenser are connected via piping to form a circulation path for the refrigerant and absorption liquid, and from the generator to the absorber, an absorption liquid pump is installed in the middle. The system is equipped with an absorption liquid piping system that uses the absorption liquid that flows out from the absorption liquid pump, and an extraction device that extracts non-condensable gas from inside the machine using the absorption liquid that flows out from the absorption liquid pump. In an absorption heat pump that extracts a heated fluid at a higher temperature than the heat source fluid from the absorber, it is installed in the middle of the refrigerant piping from the condenser to the evaporator, and connects the refrigerant liquid from the condenser and the heat source fluid from the evaporator. A refrigerant heat exchanger that exchanges heat is installed in the middle of the absorption liquid piping from the outlet side of the absorption liquid pump to the extraction device, and it exchanges heat between the absorption liquid from the absorption liquid pump and the refrigerant liquid from the refrigerant heat exchanger. An absorption heat pump characterized by being equipped with an absorption liquid heat exchanger. 2. Connect the evaporator, absorber, generator, and condenser with piping to form a circulation path for the refrigerant and absorption liquid, and use the absorption liquid flowing out from the absorption liquid pump connected to the generator to clean the inside of the machine. In an absorption heat pump that is equipped with an extraction device that extracts condensed gas, supplies heat source fluid to the evaporator and generator, flows cooling water to the condenser, and extracts hot water at a higher temperature than the heat source fluid from the absorber. A refrigerant heat exchanger that exchanges heat between the refrigerant liquid sent to the evaporator and the heat source fluid flowing out from the evaporator or generator, and the absorption liquid flowing out from the absorption liquid pump and sent to the extraction device and the refrigerant heat exchanger flowing out from the refrigerant heat exchanger. An absorption heat pump characterized by comprising an absorption liquid heat exchanger for exchanging heat with a refrigerant liquid.