JPH0694962B2 - Absorption air conditioner - Google Patents

Description

Description: FIELD OF THE INVENTION The present invention relates to an absorption type air conditioner.

2. Description of the Related Art Recently, there is an indoor air conditioner that uses an absorption refrigerator. Conventionally, an absorption air conditioner of this type is composed of an outdoor unit that performs an absorption refrigeration operation and an indoor unit that performs only a heat exchange operation, and heat transfer circulated between the outdoor unit and the indoor unit. Water was used as a medium (hereinafter referred to as a heat medium). This heat medium is separated from the heat medium (refrigerant) in the outdoor unit. For example, during cooling, the heat medium from the indoor unit is guided to the evaporator and indirectly cooled, and also during heating. In the case, it was guided to the regenerator and indirectly heated.

Problems to be Solved by the Invention According to the above conventional configuration, since water is used as the heat medium circulated between the outdoor unit and the indoor unit, there is a problem that it freezes in the winter, and There is a problem that the heat exchange efficiency is poor because water, which is the heat medium on the indoor unit side, is indirectly exchanged with the heat medium on the outdoor unit side.

Therefore, it is an object of the present invention to provide an absorption air conditioner capable of solving the above problems.

Means for Solving the Problems In order to solve the above-mentioned problems, the absorption air conditioner of the present invention has an evaporator that evaporates water as a heat transport medium, and an odor that is an absorption liquid for water vapor generated in the evaporator. An absorber that absorbs the lithium fluoride aqueous solution, a regenerator that absorbs water vapor and heats the diluted absorbent that has become thin, and a gas-liquid separator that separates water vapor from the diluted absorbent heated by this regenerator. A condenser for condensing water vapor, an indoor heat exchanger arranged in the room for exchanging heat with indoor air, and a first rare absorbent transfer for transferring the rare absorbent in the absorber to the regenerator With a tube,
A second rare absorbent transfer pipe for transferring the rare absorbent heated in the regenerator to the gas-liquid separator, a condensed water transfer pipe for transferring water from the condenser to the evaporator, and the gas-liquid separator. The concentrated absorbent transfer pipe for transferring the concentrated absorbent separated into the absorber to the absorber; the first water transfer pipe for supplying the water cooled by the heat of vaporization in the evaporator to the indoor heat exchanger; A second water transfer pipe for returning the water discharged from the heat exchanger to the evaporator, and a third water transfer pipe for transferring the water in the first water transfer pipe to the middle of the first diluted absorbent transfer pipe
A water transfer pipe and a fourth water transfer pipe for transferring the water in the second dilute absorption liquid transfer pipe into the first water transfer pipe at a position downstream of the connecting portion of the first water transfer pipe with the third water transfer pipe. And a fifth water transfer pipe for transferring the water in the second water transfer pipe into the first water transfer pipe at a position upstream of a connection portion of the first water transfer pipe with the third water transfer pipe. .

Action (i) During cooling The water, which has been deprived of the heat of vaporization by flash evaporation in the evaporator and cooled, enters the indoor heat exchanger through the first water transfer pipe,
Cool indoor air. The water that has taken the heat of the indoor air and has become warm enters the evaporator through the second water transfer pipe, is cooled again here, and is circulated and used in the indoor heat exchanger. Of course, the water vapor generated in the evaporator becomes water by the absorption cycle, and is returned to the evaporator again as water for the refrigerant through the condensed water transfer pipe.

(Ii) During heating In this case, only the regenerator is used.

That is, the water serving as the heat medium is sent to the regenerator via the third water transfer pipe and the first diluted absorbent transfer pipe, and is heated to a predetermined temperature there. Then, it is sent to the indoor heat exchanger via the fourth water transfer pipe and the first water transfer pipe to warm the indoor air.
The water whose temperature has dropped here is sent again to the third water transfer pipe via the second water transfer pipe and the fifth water transfer pipe, and is circulated and used.

Embodiment An embodiment of the present invention will be described below with reference to the drawings.

The absorption type air conditioner in the present embodiment includes an evaporator 1 for evaporating water as a heat transport medium (hereinafter referred to as a heat medium),
An absorber 3 having an aqueous lithium bromide (LiBr) solution (hereinafter referred to as an absorbing liquid) that guides the water vapor generated in the evaporator 1 through the communication part 2 and absorbs the water vapor, The regenerator 4 for heating the diluted rare absorbent, the gas-liquid separator 5 for separating water vapor from the rare absorbent heated by the regenerator 4, and the steam separated in the gas-liquid separator 6 A condenser 7 for guiding the water vapor through the communication part 6 and condensing the water vapor, an indoor heat exchanger 8 arranged in the room for exchanging heat with the indoor air, a solution pump 9 and a first three-way switch on the way. It has a valve 10 and has a first rare absorbent transfer pipe 11 for transferring the rare absorbent in the absorber 3 to the regenerator 4, and a second three-way switching valve 12 in the middle, and is heated by the regenerator 4. Second rare absorbent that transfers the lean absorbent to the gas-liquid separator 5 A transfer pipe 13 and a condensed water transfer pipe 14 for transferring the condensed water condensed in the condenser 7 to the evaporator 1,
A concentrated absorbent transfer pipe 15 for transferring the concentrated absorbent separated by the gas-liquid separator 5 to the absorber 3, a water pump 16 and an opening / closing valve 17 in the middle, and cooling by the heat of vaporization in the evaporator 1 A first water transfer pipe 18 for supplying the generated water to the indoor heat exchanger 8, an outlet of the indoor heat exchanger 8 and a condensed water transfer pipe
14 A second water transfer pipe 20 which is connected to the middle of the water and has a third three-way switching valve 19 on the way to return the water discharged from the indoor heat exchanger 8 to the evaporator 1, and the first water. A portion of the transfer pipe 18 between the water pump 16 and the opening / closing valve 17 and the first dilute absorbent transfer pipe 11
The first three-way switching valve 10 on the way is connected across the first
A third water transfer pipe 21 for transferring the water in the water transfer pipe 18 to the middle of the first diluted absorbent transfer pipe 11, a position downstream of the opening / closing valve 17 of the first water transfer pipe 18 and a second rare absorbent transfer. A fourth water transfer pipe 22 connected to the second three-way switching valve 12 in the middle of the pipe 13 to transfer the water heated by the regenerator 4 into the first water transfer pipe 18, and the first water transfer In order to guide the water discharged from the indoor heat exchanger 8 to the regenerator 4 side by being connected to the upstream side of the water pump 16 of the pipe 18 and the third three-way switching valve 19 in the middle of the second water transfer pipe 20. The fifth
A water transfer pipe 23 and a heat recovery heat exchanger 24 arranged between the first rare absorbent transfer pipe 11 and the concentrated absorbent transfer pipe 15.
And a fan 25 for removing heat from the absorber 3 and the condenser 7. Reference numeral 26 is a temperature detector for detecting the temperature of the liquid in the second dilute absorption liquid transfer pipe 13, and controls the gas supply valve 27 to the burner in the regenerator 4 to keep the temperature constant. . Further, 28 is a pressure detector for detecting the pressure in the gas-liquid separator 5, which controls the opening / closing control valve 30 in the middle of the bypass pipe 29 for returning the concentrated absorbing liquid directly to the absorber 3 so that the pressure does not rise too much. I have to.

Next, the operation will be described.

In this description, since the operation as the absorption refrigerator is known, only the operation of the part showing the features of the present invention will be described.

(I) During cooling In this case, switching and opening / closing of each three-way switching valve 10, 12, 19
The open / closed state of 17 is set as shown by arrow A in FIG.

Therefore, the water whose vaporization heat is removed by flash evaporation in the evaporator 1 and is cooled to about 7 ° C. enters the indoor heat exchanger 8 through the first water transfer pipe 18 and cools the indoor air. The water that took away the heat of the room air to about 12 ℃ is the second water transfer pipe.
It returns to the evaporator 1 via 20 and is again cooled here to about 7 ° C. and circulated to the indoor heat exchanger 8. Of course, the water vapor generated in the evaporator 1 becomes water by the absorption cycle and is returned to the evaporator 1 again as water for the refrigerant through the condensed water transfer pipe 14.

As described above, since the heat medium, water, is directly flash-evaporated by the evaporator 1, the evaporation temperature can be increased from 4 ° C. to 7 ° C. as compared with the conventional indirect type. The temperature of the cooling water on the supply side is normally set to 7 ° C and the temperature on the return side is set to 12 ° C. In this case, the adjacent absorber 3
In this case, the absorption liquid with a concentration of about 60% is made to absorb water vapor, and the temperature of the absorption liquid at that time is 44 ° C (4 ° C of 4 ° C, as indicated by points a and b in the graph of FIG. From) 4
It will be about 7.5 ℃ (at 7 ℃). Therefore, the temperature difference for heat exchange with the air in the absorber 3 is 1.39 times from 9 ° C to 12.5 ° C under the air inlet condition, and the heat transfer area is greatly reduced to cool the same cooling load. be able to.

(Ii) During heating In this case, the on-off valve 17 is closed and each three-way switching valve
The switching states 10, 12, 19 are set as indicated by the arrow B in FIG. 2 and only the regenerator 4 is used.

That is, the water serving as the heat medium is supplied to the third water transfer pipe 21 and the first water transfer pipe 21.
It is sent to the regenerator 4 via the dilute absorption liquid transfer pipe 11 and heated there to, for example, 60 ° C. to 80 ° C. Then, it is sent to the indoor heat exchanger 8 via the fourth water transfer pipe 22 and the first water transfer pipe 18,
Warm the room air. Here, the water whose temperature has dropped to about 55 ° C. is sent again to the third water transfer pipe 21 via the second water transfer pipe 20 and the fifth water transfer pipe 23, and is circulated and used.

By the way, in this way, during heating, since water as a heat medium flows through a part of the first rare absorbent transfer pipe 11, it is mixed with the rare absorbent having a concentration of about 55% flowing during cooling,
It becomes a thin lithium bromide aqueous solution with a concentration of 15% to 35%. Thus, when the concentration of the lithium bromide aqueous solution is set within the range of 15% to 35%, as shown in FIG. 4, the precipitation temperature of lithium bromide corresponding to this concentration, that is, the freezing point is -8 ° C to -55%.
℃. Therefore, when the heating operation is stopped in the winter, the heat medium, water, hardly freezes.

Next, another embodiment will be described with reference to FIG.

This has shown the case where the absorber 3 was made into 3 steps | paragraphs in the above-mentioned Example, and has the same effect as the above-mentioned Example. In the drawing, the same parts as those in the above-described embodiment are designated by the same reference numerals and the description thereof will be omitted.
Further, in the figure, 31 is a dilute absorbent liquid interstage transfer pipe for transferring the dilute absorbent liquid generated in the absorber 3 in the previous stage to the absorber 3 in the next stage, 32
Is a degassing tank connected to the absorber 3 and the diluted absorbent interstage transfer pipe 31 on the final stage side.

EFFECTS OF THE INVENTION According to the configuration of the present invention described above, in the absorption cycle, the water absorbed by the absorbing liquid is directly transferred to the heat exchanger for heat exchange, so that compared to the case of the conventional indirect type. As a result, the heat exchange efficiency can be improved, and therefore the heat transfer area in the absorber or the like can be reduced, which leads to downsizing of the device. Also, during heating in winter, the heat medium, water, is made to flow through a part of the rare absorbent transfer pipe to mix the rare absorbent, so the freezing point of the water drops, and therefore water is lost when operation is stopped. Is never frozen.

[Brief description of drawings]

FIG. 1 is a flow diagram showing a schematic configuration of an absorption air conditioner according to an embodiment of the present invention, and FIG. 2 is a flow diagram illustrating the same operation.
FIG. 3 is a graph showing the relationship between temperature and pressure of the aqueous lithium bromide solution with concentration as a parameter, FIG. 4 is a graph showing the solubility of the aqueous lithium bromide solution, and FIG. 5 is an absorption formula of another embodiment. It is a flowchart which shows schematic structure of an air conditioner. DESCRIPTION OF SYMBOLS 1 ... Evaporator, 3 ... Absorber, 4 ... Regenerator, 5 ... Gas-liquid separator, 7 ... Condenser, 8 ... Indoor heat exchanger, 10 ... First three-way switching valve, 11 ... First rare absorbent transfer Pipe, 12 ... Second three-way switching valve, 13
... second rare absorbent transfer pipe, 14 ... condensed water transfer pipe, 15 ... concentrated absorbent transfer pipe, 17 ... open / close valve, 18 ... first water transfer pipe, 19 ... third three-way switching valve, 20 ... second water Transfer pipe, 21 ... Third water transfer pipe, 22 ...
Fourth water transfer pipe, 23 ... Fifth water transfer pipe.

Front page continued (72) Inventor Masaharu Furuji 1-6-14 Edobori, Nishi-ku, Osaka City, Osaka Prefecture Hitachi Shipbuilding Co., Ltd. (72) Shinji Sakabata 1-6-14 Edobori, Nishi-ku, Osaka City, Osaka Hitachi Zosen Incorporated (72) Inventor Yosuke Kawauchi 1-6-14 Edobori, Nishi-ku, Osaka City, Osaka Prefecture Hitachi Shipbuilding Co., Ltd. (72) Inventor Tatsuhiko Umeda 1-6-14 Edobori, Nishi-ku, Osaka City, Hitachi, Ltd. In-house (72) Inventor Hideaki Okamoto 1-6-14 Edobori, Nishi-ku, Osaka City, Osaka Prefecture Hitachi Shipbuilding Co., Ltd. (72) Inventor Takeshi Yano 1-6-14 Edobori, Nishi-ku, Osaka City, Osaka Prefecture Hitachi Shipbuilding Co., Ltd. (72) Inventor Mitsufumi Matsuda 1-6-14 Edobori, Nishi-ku, Osaka City, Osaka Prefecture Hitachi Shipbuilding Co., Ltd.

Claims (1)

[Claims] 1. An evaporator for evaporating water, which is a heat transport medium, an absorber for absorbing water vapor generated in the evaporator into an aqueous solution of lithium bromide, which is an absorbing liquid, and a water vapor absorbing to reduce the concentration. Between the regenerator that heats the diluted absorbent, the gas-liquid separator that separates the steam from the diluted absorbent heated by the regenerator, the condenser that condenses the steam, and the indoor air that is placed in the room. Indoor heat exchanger for exchanging heat with the first absorber, the first rare absorbent transfer pipe for transferring the rare absorbent in the absorber to the regenerator, and the rare absorbent heated by the regenerator to the gas-liquid separator. A second dilute absorbent transfer pipe for transferring, a condensed water transfer pipe for transferring water from the condenser to the evaporator, and a concentrated absorbent for transferring the concentrated absorbent separated by the gas-liquid separator to the absorber. The transfer pipe and the water cooled by the heat of vaporization in the evaporator are supplied to the indoor heat exchanger. A first water transfer tube, a second water transfer pipe for returning the water leaving from the indoor heat exchanger to said evaporator,
The third water transfer pipe for transferring the water in the first water transfer pipe to the middle of the first diluted absorbent transfer pipe, and the water in the second diluted absorbent transfer pipe,
The fourth water transfer pipe which transfers into the first water transfer pipe at a position downstream of the connection portion of the first water transfer pipe with the third water transfer pipe, and the water in the second water transfer pipe, An absorption air conditioner comprising: a fifth water transfer pipe that transfers the water into the first water transfer pipe at a position upstream of a connection portion with the third water transfer pipe.