JP2695923B2 - Air-cooled absorption chiller / heater - Google Patents

Description

Description: TECHNICAL FIELD The present invention relates to an air-cooling absorption chiller / heater, and is used, for example, as a chiller / heater for building air conditioning. The present invention relates to an air-cooling absorption type chiller / heater suitable for increasing the absorption refrigeration capacity by circulating a surfactant so as to lower the surface tension.

[Conventional technology]

A conventional apparatus is, for example, a water-cooled absorption refrigeration apparatus in which a condenser is provided at an upper portion and an absorber and an evaporator are provided at a lower portion, as described in JP-B-59-36173. In addition, a surfactant separator is disposed in a refrigerant flow path connecting the condenser and the evaporator, and supplies a surfactant vapor to the absorber.

[Problems to be solved by the invention]

The prior art described above does not consider air-cooled devices.

In the case of an air-cooled absorption type chiller / heater, when the absorber and the condenser are arranged at substantially the same position, the liquid refrigerant and the surfactant are used by utilizing the pressure difference between the condenser, the absorber and the evaporator. It is conceivable to circulate, but when the cooling air temperature changes suddenly, that is, when rain suddenly falls or gusts blow, the amount of condensate temporarily increases, while the differential pressure decreases However, there has been a problem that stable circulation is not performed and the solution flows back into the separator.

The present invention has been made in order to solve the above-mentioned problems in the prior art, and in an air-cooled absorption type chiller / heater in which an air-cooled absorber and an air-cooled condenser are arranged at substantially the same level, An object of the present invention is to provide an air-cooled absorption chiller / heater capable of increasing the absorption refrigeration capacity by separating a surfactant, returning it to a concentrated solution system, and circulating the surfactant stably. It is.

[Means for solving the problem]

To achieve the above objectives, high-temperature regenerator, low-temperature regenerator, air-cooled condenser, evaporator, air-cooled absorber, solution heat exchanger,
In an air-cooling absorption type chiller / heater, comprising a solution pump, a refrigerant pump, and a piping system operatively connecting these, and circulating a surfactant for lowering the surface tension of the refrigerant and the solution, The air-cooled condenser is arranged at the same level, and the surfactant separator communicating with the air-cooled condenser in the gas phase is arranged at a position higher than the lower header of the air-cooled absorber and the lower header of the air-cooled condenser. A means for pumping the liquid refrigerant of the air-cooled condenser is provided to the surfactant separator, and a flow path for returning the separated surfactant to the concentrated solution system is provided.

It should be noted that the purpose of the above is to arrange the surfactant separator at a position sufficiently higher than the lower header of the absorber, that is, at a position higher than the liquid level when most of the solution in the cycle enters the absorber. In order to circulate the separated surfactant by utilizing the position head difference, the pumping means pumps the liquid refrigerant of the condenser to the surfactant separator, thereby achieving the above. Is done.

[Action]

The surfactant separator is disposed above the lower header of the air-cooled absorber, and the liquid refrigerant is sent from the lower header of the air-cooled condenser by pump means. The surfactant separator is in communication with the gas phase of the air-cooled condenser.

The surfactant flowing out of the surfactant separator can be circulated to the air-cooled absorber with a low pressure and a low liquid level in the machine at a low pressure and a low position, so that the surfactant can be stably used. Can be circulated and no backflow of the solution into the surfactant separator occurs.

In addition, the pump means sends the surfactant-mixed liquid solvent to the surfactant separator for separation, so that the liquid refrigerant and the surfactant flow out of the separator at a head difference in position, and the surfactant separation is performed. There is no occurrence of poor separation due to stagnation of the liquid refrigerant and the surfactant in the vessel.

〔Example〕

Hereinafter, embodiments of the present invention will be described with reference to FIG. 1 and FIG.

FIG. 1 is a cycle diagram of an air-cooling absorption chiller / heater according to an embodiment of the present invention.

In FIG. 1, 1 is a high-temperature regenerator, 2 is a low-temperature regenerator,
3 is an air-cooled condenser, 4 is an evaporator, 5 is an air-cooled absorber, 6 is a low-temperature heat exchanger related to a solution heat exchanger, 7 is a high-temperature heat exchanger related to a solution heat exchanger, and 8 is a solution pump. The solution circulation pump according to the present invention, 9a and 9b are the solution spray pumps related to the solution pump, and 10
Denotes a refrigerant spray pump relating to the refrigerant pump, 11 denotes a liquid pumping tube constituting a means for pumping a liquid refrigerant, and 12 denotes a surfactant separator.

In FIG. 1, 13 is a conduit leading from the low-temperature regenerator 2 to the lower part of the liquid pumping pipe 11, 14 is a lower header of the air-cooled condenser 3, 5a is a lower header of the air-cooled absorber 5, 15 Is a conduit for the liquid refrigerant from the lower header 14 of the air-cooled condenser 3 to the opening 16 at the lower part of the pumping pipe 11, and 17 is a conduit relating to the flow path of the surfactant. The surfactant separated by the agent separator 12 is transferred from the low-temperature regenerator 2 to the low-temperature heat exchanger 6.
A conduit for returning to the concentrated solution tube 27 leading to Reference numeral 18 denotes a moat weir provided in the surfactant separator 12, and the liquid refrigerant and the surfactant are separated through the moor weir 18. Reference numeral 19 denotes a U-shaped refrigerant liquid seal tube for connecting the liquid refrigerant portion of the surfactant separator 12 to the evaporator 4, and 20 denotes a lower header of the evaporator 4 and the air-cooled absorber.
This is a conduit for refrigerant overflow that connects to 5a.

Further, 24 is a steam duct for connecting the low-temperature regenerator 2, the surfactant separator 12 and the air-cooled condenser 3 in the gas phase, and 25 is for connecting the evaporator 4 and the air-cooled absorber 5 in the gas phase. The steam duct 26 is a fan that supplies cooling air to the air-cooled condenser 3 and the air-cooled condenser 5.

As shown in FIG. 1, the surfactant separator 12 is disposed at a position higher than the lower header 5a of the air-cooled absorber 5, and has an air-cooled condenser substantially at the same level as the lower header 5a of the air-cooled absorber. A conduit 15 and a pumping line 11 are provided as means for pumping the liquid refrigerant in the lower header 14 of the vessel 3.

The air-cooled condenser 3 and the air-cooled absorber 5 are cross-fing-ube type exchangers composed of a vertical tube group fitted orthogonally to a plurality of fans, in which cooling air flows through the fin side, Refrigerant vapor is introduced into the tube.

Next, the operation of the air-cooling absorption chiller / heater having such a configuration will be described.

In the present apparatus, water is used as a refrigerant, an aqueous solution of lithium bromide is used as an absorbent, and n-octyl alcohol is used as a surfactant that lowers the surface tension of the refrigerant and the absorbent.

The lithium bromide aqueous solution of the high-temperature regenerator 1 is heated by the combustion gas of the external heat source to generate refrigerant vapor, and becomes a concentrated solution having a high lithium bromide concentration. The generated refrigerant vapor is introduced into the heat transfer tube of the low-temperature regenerator 2, heats the lithium bromide aqueous solution outside the tube to condense and liquefy, and is introduced into the lower end of the liquid pumping tube 11 via the conduit 13. . The solution in the low-temperature regenerator 2 is heated to generate refrigerant vapor, and becomes a concentrated solution.

The generated refrigerant vapor is introduced into the vertical pipe of the air-cooled condenser 3 through the vapor duct 24, and is cooled by the cooling air of the fan 26 and condensed and liquefied. The liquid refrigerant flows from the lower header 14 to the conduit 15
The liquid is introduced into the lower part of the liquid pumping pipe 11 via.

On the other hand, the liquid refrigerant from the high-temperature regenerator 1 introduced into the pumping pipe 11 by the conduit 13 is mixed with the liquid refrigerant generated in the air-cooled condenser 3, and the inside of the pumping pipe 11 is gas-liquid two-phase. As a result, the refrigerant vapor is introduced into the surfactant separator 12, and only the refrigerant vapor flows into the air-cooled condenser 3 again through the vapor duct 24. This is because the liquid refrigerant flowing from the conduit 13 is higher in temperature than the saturation temperature in the air-cooled condenser 3 and self-boiling in the liquid-lifting pipe 11 to form a gas-liquid two-phase. That is, the lower header 14 and the pumping pipe
In comparison with the liquid header pressure due to the liquid refrigerant between the opening 16 of the conduit 15 to the opening 11, the opening 16 and the upper end of the pumping tube 11, that is, from the opening of the surfactant separator 12. The sum of the liquid head pressure of the gas-liquid two-phase and the flow pressure loss thereof is small, so that the gas-liquid two-phase rises through the liquid pumping tube 11.

In the surfactant separator 12, the low-density surfactant n-octyl alcohol is separated at the top, and
After passing through 17, it is returned to the concentrated solution tube 27 of the low-temperature regenerator 2.

In addition, the liquid refrigerant flows into the evaporator 4 through the stagnation weir 18 through the U-shaped refrigerant liquid seal tube 19.

The liquid refrigerant in the evaporator 4 is spread on the heat transfer tubes by the refrigerant spray pump 10 and evaporates by taking heat from cold water flowing in the heat transfer tubes. The refrigerant vapor generated in the evaporator 4 is guided to the vertical pipe of the air-cooled absorber 5 through the steam duct 25, and is absorbed by the concentrated solution from the high-temperature regenerator 1 and the low-temperature regenerator 2. The heat absorbed at that time is cooled by the cooling air of the fan 26. The solution that has become thin by absorbing the refrigerant vapor is separated into two by a solution circulation pump 8 through a low-temperature heat exchanger 6, one of which is sent to the low-temperature regenerator 2, and the other is further heated to a high temperature by the high-temperature heat exchanger 7. Sent to the vessel 1. The air-cooling absorption refrigeration cycle is configured as described above.

Here, at the start of operation or when the cooling air temperature is particularly low, the pressure difference between the high-temperature regenerator 1 and the low-temperature regenerator 2 and the air-cooled absorber 5 is smaller than during rated operation. However, since the opening 19a of the U-shaped refrigerant seal pipe 19 to the evaporator 4 is lower than the surfactant separator 12 and the liquid refrigerant liquid level, the liquid refrigerant evaporates only by the head difference of the position of the liquid refrigerant. Vessel 4
Therefore, the liquid refrigerant does not accumulate in the surfactant separator 12. Therefore, poor separation of the surfactant and poor circulation of the liquid refrigerant do not occur. In addition, since the surfactant also flows into the concentrated solution system due to the head difference of the liquid, the surfactant separator
There is an effect that smooth driving can be performed without being accumulated in the interior of the vehicle.

In this embodiment, the liquid refrigerant in the lower header 14 of the air-cooled condenser 3 is heated by the low-temperature regenerator 2 and the high-temperature liquid refrigerant condensed by the self-boiling action of the bubble pumping action of the high-temperature surfactant separator.
Since the pump is pumped to 12, the pump device has no mechanical parts, has high reliability, and has the advantage that no electric power is required.

As described above, according to the present embodiment, the liquid refrigerant containing the surfactant is pumped to a position higher than the lower header of the condenser, that is, the lower header of the absorber, and therefore, even when the pressure difference between the condenser and the absorber fluctuates. The liquid refrigerant can be reliably sent from the separator to the evaporator.

Similarly, there is an effect that the surfactant can be surely mixed into the concentrated solution system.

Next, FIG. 2 is a cycle diagram of an air-cooling absorption chiller / heater according to another embodiment of the present invention. In the figure, those having the same reference numerals as those in FIG. 1 are the same as those in the previous embodiment.
The description is omitted.

The embodiment shown in FIG. 2 is different from the first embodiment in that a refrigerant pump 23 is disposed below the lower header 14 of the air-cooled condenser 3 so as to pump liquid refrigerant to the surfactant separator 12A via the conduit 15A. It differs from the embodiment of FIG.

That is, in the embodiment shown in FIG. 2, the refrigerant from the high-temperature regenerator 1 that has heated the low-temperature regenerator 2 is sent to the vapor duct 24 by the conduit 13A, and partially self-evaporates. Flows down to the surfactant separator 12A.
Here, the surfactant is almost evaporated in the high-temperature regenerator 1,
The amount of evaporation in the low-temperature regenerator 2 is small. Therefore, the amount of surfactant mixed into the refrigerant from the conduit 13A is much larger than that mixed into the refrigerant in the condenser of the conduit 15A. Since this flows in from the upper part of the separator 12A, the surfactant having a low density is separated to the upper part.

A liquid level relay 22 is provided in the liquid tank 21 of the lower header 14 of the air-cooled condenser 3 in order to prevent the refrigerant pump 23 constituting the means for pumping the liquid refrigerant of the air-cooled condenser 3 to the surfactant separator 12A from idling. The ON / OFF control of the refrigerant pump 23 is performed according to the output signal of the liquid level relay 22.

On the other hand, a conduit 17A is connected to the conduit 20 as a flow path for returning the separated surfactant to the concentrated solution system, and is sent to the air-cooled absorber 5 via the conduit 20.

According to the embodiment shown in FIG. 2, the same effect as that of the previous embodiment is expected, and there is a specific effect that the surfactant separator 12A can be downsized.

〔The invention's effect〕

As described above, according to the present invention, in an air-cooled absorption chiller / heater in which an air-cooled absorber and an air-cooled condenser are arranged at substantially the same level, a surfactant is separated from the liquid refrigerant of the condenser. Thus, it is possible to provide an air-cooled absorption chiller / heater capable of improving absorption refrigeration capacity by reliably returning to a concentrated solution system and circulating the solution stably.

[Brief description of the drawings]

FIG. 1 is a cycle diagram of an air-cooled absorption chiller / heater according to one embodiment of the present invention, and FIG. 2 is a cycle diagram of an air-cooled absorption chiller / heater according to another embodiment of the present invention. . 1 high-temperature regenerator, 2 low-temperature regenerator, 6 air-cooled condenser, 4 evaporator, 5 air-cooled absorber, 6 low-temperature heat exchanger, 7 high-temperature heat exchanger, 8 ... solution circulation pump, 9
a, 9b …… solution spray pump, 10 …… refrigerant spray pump,
11… Pumping pipe, 12,12A …… Surfactant separator, 13,13A…
… Conduit, 14 …… lower head, 15,15A …… conduit, 17,17A…
... conduit, 19 ... U-shaped refrigerant liquid seal tube, 23 ... refrigerant pump.

 ────────────────────────────────────────────────── ─── Continuing on the front page (72) Inventor Shigeyoshi Kurosawa 2-26 Kanamecho, Toshima-ku, Tokyo (72) Inventor Yoshikazu Nagaoka 5-22-4 Kami-Soshigaya Heights 302, Kami-Sogaya Heights 302 (72) Inventor Shinichi Kanou 4-9-1-4-303 Takawashi, Habikino-shi, Osaka (72) Inventor Sadahisa Takemoto 11-8, Tonencho, Chigusa-ku, Nagoya, Aichi, Japan 502 Hitachi Machinery Co., Ltd. (72) Inventor Tamio Shimizu 603 Kandamachi, Tsuchiura-shi, Ibaraki Pref. Hitachi Works Tsuchiura Plant (56) References JP-A-63-201460 (JP, A) JP Showa 57-98764 (JP, A)

Claims (1)

(57) [Claims] 1. A high-temperature regenerator, a low-temperature regenerator, an air-cooled condenser, an evaporator, an air-cooled absorber, a solution heat exchanger, a solution pump, a refrigerant pump, and a piping system operatively connecting these components. In an air-cooled absorption chiller / heater that circulates a surfactant that lowers the surface tension of the solution,
The air-cooled absorber and the air-cooled condenser are arranged at the same level, and the surfactant separator communicating with the air-cooled condenser in the gas phase is higher than the lower header of the air-cooled absorber and the lower header of the air-cooled condenser. And a means for pumping the liquid refrigerant of the air-cooled condenser to the surfactant separator, and a flow path for returning the separated surfactant to a concentrated solution system is provided. Type hot / cold water heater.