KR20030081153A - Absorption refrigerator - Google Patents

Abstract

The recovery amount of heat retained by the exhaust gas from the combustion apparatus additionally provided to the high temperature regenerator is increased.

The first, second and third exhaust gas heat recoverers 23, 24 and 25, which heat exchange with the lean absorbent liquid and dissipate the exhaust gas, are provided, and the distribution control valves 26 and 27 are provided. In addition, the distribution control valve 27 is controlled so that the temperature sensor 29 continues to detect a predetermined temperature (an appropriate temperature higher than the dew point of steam contained in the exhaust gas, for example, 100 ° C), and the distribution control valve. (26) was set so that the controller 30 which controls the temperature which the temperature sensor 28 detects is maintained in predetermined | prescribed temperature (for example, 40 degreeC slightly higher than the crystallization temperature of rich absorbent liquid) is provided. In addition, the third exhaust gas heat recovery machine 25 and the downstream exhaust pipe 22 were formed to be formed of weather resistant steel or antirust steel.

Description

Absorption Chillers {ABSORPTION REFRIGERATOR}

The present invention relates to an absorption chiller.

As shown in Fig. 2, the exhaust gas discharged from the gas burner 2 for heating and boiling the lean absorbent liquid of the high temperature regenerator 1 is disposed between the high temperature heat exchanger 10 and the high temperature regenerator 1 of the absorbent liquid pipe 11. The first exhaust gas heat recovery unit 23 provided in the first and second exhaust gas heat recovery unit 24 provided between the low temperature heat exchanger 9 and the high temperature heat exchanger 10 are sequentially transferred to the high temperature from the absorber 7. Absorption type refrigerators designed to raise the temperature of the lean absorbent liquid conveyed to the regenerator 1, reduce the required heating amount by the gas burner 2, and reduce fuel consumption are widely known.

That is, in the absorption type refrigerator of the said structure, the lean absorbent liquid of about 40 degreeC discharged | emitted from the absorber 7 is the same as the low temperature heat exchanger 9, the 2nd exhaust gas heat recovery machine 24, and high temperature Since it is heated in each of the heat exchanger 10 and the 1st exhaust gas heat exchanger 23, it rises about 140 degreeC, and it flows into the high temperature regenerator 1, and it can save the fuel consumed by the gas burner 2 ,.

In addition, when the temperature of the exhaust gas emitted from the gas burner 2 and the temperature of the lean absorbent liquid supplied from the absorber 7 are both low, the opening degree of the flow control valve 26X is enlarged and the second exhaust gas heat recoverer 24 is opened. Increases the amount of lean absorbent liquid flowing by bypass, reduces the heat recovery from the exhaust gas in the second exhaust gas heat recovery unit 24 to prevent a significant drop in the exhaust gas temperature, and condensation and condensation of water vapor contained in the exhaust gas. It is configured to prevent.

However, in the absorption chiller of the above-mentioned conventional structure, even if the temperature of the exhaust gas decreases until the water vapor contained in the exhaust gas condenses and condenses, this temperature is higher than the temperature of the lean absorbent liquid discharged from the absorber, and thus can be used. Since the recovery of heat has not yet sufficiently fallen off, it is necessary to recover the heat retained by the exhaust gas again by the delivery line of the absorption chiller, which is a problem to be solved.

The present invention provides a high temperature regenerator for evaporating and separating a refrigerant by heating and boiling in a combustion apparatus, obtaining a refrigerant vapor and an intermediate absorbent liquid from a lean absorbent liquid, and an intermediate absorbent liquid generated and supplied by the high temperature regenerator. The low temperature regenerator which is heated by the refrigerant vapor generated by the high temperature regenerator and evaporates and separates the refrigerant again, and obtains the refrigerant vapor and the rich absorbent liquid from the intermediate absorbent liquid, and the refrigerant liquid which is condensed by heating the intermediate absorbent liquid in this low temperature regenerator is supplied A condenser that cools the refrigerant vapor generated and supplied by the regenerator to obtain a refrigerant liquid, an evaporator in which the refrigerant liquid supplied from the condenser is scattered on the heat transfer tube to extract heat from the fluid flowing in the heat transfer tube, and the refrigerant evaporates. The refrigerant vapor generated and supplied is increased from the low temperature regenerator Is absorbed in the rich absorbent liquid supplied to the lean absorbent liquid and supplied to the high temperature regenerator, the low temperature heat exchanger in which the lean absorbent liquid entering and exiting the absorber and the rich absorbent liquid exchanges, and the intermediate absorbent liquid entering the high temperature regenerator and the lean absorbent liquid. An absorption chiller having a high temperature heat exchanger for heat exchange, comprising: an exhaust gas heat recovery unit in which a lean absorbent liquid bypassing the low temperature heat exchanger and a discharge gas discharged from the combustion device exchange heat, and a flow rate for controlling the amount of the lean absorbent liquid flowing through the low temperature heat exchanger Absorption freezer of the 1st structure which installed a control means,

The absorption chiller of the said 1st structure WHEREIN: The absorption chiller of a 2nd structure which comprised the discharge gas heat-exchanged with the lean absorbent liquid which passed the high temperature heat exchanger and / or the low temperature heat exchanger to the exhaust gas heat recovery unit, and

The absorption chiller of the said 1st or 2nd structure WHEREIN: The absorption chiller of a 3rd structure which provided at least the waste gas heat recovery machine and the waste gas pipe downstream of this waste gas heat recovery machine by weathering steel or an unclean steel is provided. will be.

1 is an explanatory diagram showing an embodiment of the present invention.

2 is an explanatory diagram showing a prior art.

<Explanation of symbols for the main parts of the drawings>

1: high temperature regenerator

2: gas burner

3: low temperature regenerator

4: condenser

6: Evaporator

7: absorber

9: low temperature heat exchanger

10: high temperature heat exchanger

11 to 13: Absorption tube

15 to 17: refrigerant tube

23: first exhaust gas heat recovery machine

24: 2nd exhaust gas heat recovery machine

25: 3rd exhaust gas heat recovery machine

26, 27: distribution control valve

28, 29: temperature sensor

An embodiment of the present invention will be described below using an absorption type refrigerator having water as a refrigerant and an aqueous lithium bromide (LiBr) solution as an absorption liquid.

An embodiment of the present invention will be described with reference to FIG. 1 is a high temperature regenerator configured to heat and separate the refrigerant by heating the absorbent liquid, for example, by the thermal power of the gas burner 2 fueled with city gas, 3 is a low temperature regenerator, 4 is a condenser, 5 is a low temperature regenerator 3 And a high temperature body in which the condenser 4 is housed, 6 an evaporator, 7 an absorber, 8 a low temperature body in which the evaporator 6 and the absorber 7 are housed, 9 a low temperature heat exchanger, 10 a high temperature heat exchanger, 11 to 13 is an absorbent liquid pipe, 14 is an absorbent liquid pump, 15 to 17 is a refrigerant pipe, 19 is a refrigerant pump, 20 is a cold water pipe, 21 is a cooling water pipe, 22 is an exhaust pipe through which exhaust gas from the gas burner 2 passes, 23 is a first exhaust gas heat recovery unit, 24 is a second exhaust gas heat recovery unit, 25 is a third exhaust gas heat recovery unit, 26 and 27 are distribution control valves, and 28 is provided in a downstream portion of the absorption liquid pipe 13 to provide a low temperature heat exchanger. (9) detects the temperature of the concentrated absorbent liquid which is heat-exchanged by heat exchange with the lean absorbent liquid. Is a temperature sensor, and 29 is a temperature sensor provided in the exhaust pipe 22 downstream of the second exhaust gas heat recovery 24 to detect the temperature of the exhaust gas heat-exchanged by heat exchange with the lean absorbent liquid in the second exhaust gas heat recovery 24. And 30 denotes that the temperature control 29 controls the distribution control valve 27 so that the temperature sensor 29 continues to detect a predetermined temperature, for example 100 ° C, while the temperature of the rich absorbent liquid detected by the temperature sensor 28 is a predetermined temperature, e.g. For example, the distribution control valve 26 is controlled to be maintained slightly above the crystallization temperature of the rich absorbent liquid, for example, 40 ° C. to distribute the lean absorbent liquid to the low temperature heat exchanger 9 and the third exhaust gas heat recoverer 25. It is a controller for doing so.

In the absorption chiller of the present invention, the third exhaust gas heat recovery unit 25 and the exhaust pipe 22 downstream from the third exhaust gas heat recovery unit 25 are formed of weather resistant steel or antirust steel.

In the absorption chiller of the above configuration, when the city gas is burned in the gas burner 2 and heated and boiled in the high temperature regenerator 1, the refrigerant vapor separated from the lean absorbent liquid and the refrigerant vapor are separated and the concentration of the absorbed liquid. It is possible to obtain an intermediate absorbent liquid having a high level.

The high temperature refrigerant vapor generated in the high temperature regenerator (1) flows into the low temperature regenerator (3) through the coolant tube (15), and is generated in the high temperature regenerator (1) and is heated by the absorbent liquid tube (12). The intermediate absorbent liquid introduced into the low temperature regenerator (3) is heated to condense heat, and flows into the condenser (4).

In addition, the refrigerant heated in the low temperature regenerator (3) and separated by evaporation from the intermediate absorbent liquid flows into the condenser (4), heat exchanges with water flowing in the cooling water pipe (21) to condense and liquefy, and condenses from the refrigerant pipe (15). The refrigerant is supplied to the evaporator 6 through the refrigerant pipe 17.

The refrigerant liquid flowing into the evaporator 6 and collected in the refrigerant liquid flow is dispersed by the refrigerant pump 19 on the heat transfer pipe 20A connected to the cold water pipe 20, and exchanges heat with water supplied through the cold water pipe 20. By evaporation, the water flowing inside the heat transfer pipe 20A is cooled.

The refrigerant evaporated in the evaporator (6) flows into the absorber (7), is heated in the low temperature regenerator (3) to evaporate and separate the refrigerant, and the absorbent liquid having a higher concentration of the absorbent liquid, that is, the low temperature heat exchanger (9). It is absorbed by the rich absorbent liquid which is supplied via) and scattered from above.

The absorbent liquid which absorbs the refrigerant in the absorber 7 and becomes thinner, ie, the lean absorbent liquid, is discharged by the low temperature heat exchanger 9, the third exhaust gas heat recovery unit 25, and the second discharge by the operation of the absorbent liquid pump 14. The gas is heated in each of the gas heat recovery unit 24, the high temperature heat exchanger 10, and the first exhaust gas heat recovery unit 23, and sent from the absorbent liquid pipe 11 to the high temperature regenerator 1.

When the absorption chiller is operated as described above, the cold water cooled by the heat of vaporization of the refrigerant in the heat transfer pipe 20A piped inside the evaporator 6 is circulated and supplied through the cold water pipe 20 to the air conditioning load (not shown). As such, cooling operation such as cooling can be performed.

And in the absorption type refrigerator of the said structure, the lean absorption liquid of about 40 degreeC of the absorber 7 conveyed to the high temperature regenerator 1 by the absorption liquid pump 14 similarly to the conventional absorption type refrigerator shown in the said FIG. Each of the low temperature heat exchanger 9, the third exhaust gas heat recovery unit 25, the second exhaust gas heat recovery unit 24, the high temperature heat exchanger 10, and the first exhaust gas heat recovery unit 23 are suitably heated. Since the temperature rises up to around 140 ° C. and is supplied to the high temperature regenerator 1, the first exhaust gas heat recovery unit 23, the second exhaust gas heat recovery unit 24, and the third exhaust gas heat recovery unit 25 are not provided. It is possible to reduce the fuel consumed in the gas burner 2 than the conventional absorption chiller.

That is, the exhaust gas of the gas burner 2 supplied through the exhaust pipe 22 has a high temperature through the absorbent liquid pipe 11 by the absorbent liquid pump 14 from the absorber 7 in the first exhaust gas heat recovery unit 23. It heat-exchanges and heat-exchanges with the whole amount of the lean absorbent liquid conveyed to the regenerator 1, and the retained heat is collect | recovered by the lean absorbent liquid.

On the other hand, in the second exhaust gas heat recoverer 24, when the temperature sensor 29 detects a temperature higher than the predetermined 100 ° C., more lean absorbent liquid is supplied to the second exhaust gas heat recoverer 24, When the temperature sensor 29 detects a temperature lower than the predetermined 100 ° C., the distribution control valve 27 causes the controller 30 to increase the amount of the lean absorbent liquid bypassing the second exhaust gas heat recoverer 24. The amount of heat recovery from the exhaust gas is controlled by the control.

Therefore, in the heat recovery from the exhaust gas in the second exhaust gas heat recovery device 24, the temperature of the exhaust gas is maintained at the predetermined 100 ° C, so that at the same time when the temperatures of the exhaust gas and the lean absorbent liquid are simultaneously low or during partial load operation. Even if the exhaust gas is discharged from the gas burner 2 and flows through the exhaust pipe 22, the temperature of the exhaust gas is lower than the dew point temperature (the dew point temperature of the combustion exhaust gas when the city gas, that is, natural gas is 60 to 70 ° C). It is maintained at a high temperature of 100 ° C., and condensation of water vapor contained in the exhaust gas does not cause drain water and causes problems of corrosion of the member due to the drain water.

In the third exhaust gas heat recovery device 25, the distribution control such that the temperature detected by the temperature sensor 28 is maintained at a predetermined temperature, for example, slightly higher than the crystallization temperature of the rich absorbent liquid, for example, 40 ° C. The valve 26 is controlled by the controller 30. For this reason, heat recovery from exhaust gas is actively performed within the range in which the temperature of the rich absorbent liquid flowing through the absorbent liquid tube 13 to the absorber 7 is maintained at a temperature slightly higher than the crystallization temperature.

At this time, even if the temperature of the exhaust gas radiated to the rich absorbent liquid is lower than the dew point of the water vapor contained in the exhaust gas, the exhaust pipe on the downstream side of the third exhaust gas heat recovery device itself and the third exhaust gas heat recovery device 25 is lowered. Since 22 is made of weather resistant steel or antirust steel, the member does not rust even after being in contact with the condenser for a long time.

Moreover, since this invention is not limited to the said embodiment, various deformation | transformation is possible in the range which does not deviate from the meaning described in the claim.

For example, the absorbing liquid pipe or the second and third discharge gas heat recovery units 24, through which the second and third discharge gas heat recovery units 24 and 25 are interposed, instead of the distribution control valves 26 and 27. , 25) are installed in the absorbing liquid pipe bypassing the same, and the second and third exhaust gas heat recoverers 24 and 25 have an appropriate amount of absorbent liquid in the same way as the absorption chillers provided with the distribution control valves 26 and 27. It is also possible to set it as the structure controlled by the controller 30 so that it may be supplied.

In addition, since the water vapor contained in the exhaust gas condenses in the third exhaust gas heat recovery unit 25, the third exhaust gas heat recovery unit 25 includes a plurality of lean absorbent liquids provided horizontally so that the condensed water is easily discharged. It is good to comprise the inside of a pipe | tube and the outside of this pipe | tube so that exhaust gas may flow to an up-down direction.

In addition, the absorption chiller is good for exclusively performing cooling operations such as cooling, and the like, and the refrigerant vapor heated and generated by the high temperature regenerator 1 and the absorption liquid obtained by evaporating and separating the refrigerant vapor can be directly supplied to the low-temperature fuselage 8. Piping is connected so that the water is heated by the gas burner (2) so that the cooling water does not flow into the cooling water pipe (21), and the water heated to about 55 DEG C in the heat transfer pipe (20A) of the evaporator 6, for example, is cold water. The hot water pipe may be circulated and supplied to the load through a pipe (when hot water circulates) 20 so that heating operation such as heating may also be performed.

In addition, as the fluid to be cooled in the evaporator 6 and supplied to the air-conditioning load and the like, water and the like are supplied without changing the phase as in the above-described embodiment, and the freon and the like are changed in phase so as to enable heat transfer using latent heat. You may also do it.

As described above, according to the present invention, it is possible to recover most of the available exhaust gas holding heat. Moreover, since the essential part is molded by weather resistant steel or antirust steel, the member does not rust even when it comes into contact with the condensate for a long time. In addition, high-priced steel materials can avoid significant increase in costs by limiting their use.

Claims (3)

The refrigerant is evaporated and separated by heating and boiling in a combustion apparatus, and a high temperature regenerator which obtains refrigerant vapor and an intermediate absorbent liquid from the lean absorbent liquid, and the intermediate absorbent liquid generated and supplied by the high temperature regenerator are heated by the refrigerant vapor generated by the high temperature regenerator to regenerate the refrigerant. A low temperature regenerator which is evaporated and separated, and obtains the refrigerant vapor and the rich absorbent liquid from the intermediate absorbent liquid, and a refrigerant liquid obtained by condensing the intermediate absorbent liquid by the low temperature regenerator is supplied, and the refrigerant vapor generated and supplied by the low temperature regenerator is cooled to cool the refrigerant liquid. A condenser obtained from the condenser, a vaporized refrigerant liquid supplied from the condenser, and dissipating heat from the fluid flowing in the heat transfer tube to extract heat from the fluid flowing through the heat transfer tube; Absorbed in the concentrated absorbent liquid supplied separately An absorption chiller comprising an absorber supplied as a liquid absorber to a high temperature regenerator, a low temperature heat exchanger in which the lean absorbent liquid entering and exiting the absorber and the rich absorbent liquid exchange heat, and a high temperature heat exchanger in which the intermediate absorbent liquid entering the high temperature regenerator and the lean absorbent liquid exchange heat. , An absorption chiller comprising: an exhaust gas heat recovery unit in which the lean absorbent liquid flowing by bypassing the low temperature heat exchanger and the exhaust gas discharged from the combustion device exchange heat; and a flow control means for controlling the amount of the lean absorbent liquid flowing by bypassing the low temperature heat exchanger. The absorption chiller according to claim 1, wherein the exhaust gas heat recovery unit is configured to introduce exhaust gas heat-exchanged with the lean absorbent liquid passing through the high temperature heat exchanger and / or the low temperature heat exchanger. The absorption chiller according to claim 1 or 2, wherein at least the exhaust gas heat recovery unit and the exhaust gas pipe downstream from the exhaust gas heat recovery unit are formed of weather resistant steel or non-rust steel.