JP2005172380A - Adsorption-type heat pump - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide an adsorption type heat pump capable of being independently operated without separately needing a heating source such as exhaust heat, and having superior energy efficiency. <P>SOLUTION: In this adsorption-type heat pump comprising two adsorption towers, a condenser, an evaporator, and a flow passage for circulating a refrigerant between the condenser and the evaporator, two adsorption towers are alternately used as an adsorber and a regenerator, the desorbed vapor from the adsorption towers is condensed by the condenser, and the condensed water is evaporated by the evaporator to exchange the heat with the fluid passing through a circulating pipe mounted in the evaporator. A vapor compressor 8 is mounted between the adsorption towers 1, 2 and heat exchanging lines 3, 4 functioned as the condensers by mounting desorbed vapor flow passage pipes 3a, 4a on the adsorption towers 1, 2, and the sensible heat of produced superheated steam and the condensed latent heat are used as the heating source for desorption. Whereby the heat pump can be independently operated without utilizing the exhaust heat and the like. <P>COPYRIGHT: (C)2005,JPO&NCIPI

Description

  The present invention relates to an adsorption heat pump that does not require exhaust heat for regeneration of an adsorbent.

  An adsorption heat pump is a device that pumps heat by using the phase change that accompanies the adsorption and desorption phenomenon of working medium (refrigerant) such as water or alcohol to a solid adsorbent such as silica gel or activated carbon. is there. FIG. 5 shows an example in which this adsorption heat pump is used as an adsorption refrigerator. Two adsorption towers 21 and 22 filled with a solid adsorbent A such as silica gel, a condenser 23 and an evaporator 24 are shown. The adsorption towers 21 and 22 are provided with an adsorber that adsorbs water vapor when water is used as a refrigerant and a regenerator that desorbs adsorbed water (water vapor) at regular operating times. Used alternately. As shown in FIG. 5, when the adsorption tower 21 is used as an adsorber and the adsorption tower 22 is used as a regenerator, the hot water flowing in the heat exchanger 25 of the adsorption tower 22 on the regenerator side is The solid adsorbent A is heated to desorb moisture previously adsorbed, the damper 26 is opened by the pressure of the desorbed water vapor, and the desorbed water vapor moves to the condenser 23 in communication with the adsorption tower 22. Then, the water is cooled and condensed by the heat exchange pipe 23 a through which the cooling water passes, and moves to the evaporator 24 via the condensed water pipe 27. The condensed water evaporates when it reaches the heat exchange pipe 24a through which the cold water in the evaporator 24 whose pressure has been reduced to a vacuum passes, and the cold water in the flow pipe 24a is rapidly removed by the heat of vaporization at this time. The temperature drops. On the other hand, the damper 26a is opened by the vapor pressure of the water, and the water vapor is adsorbed to the solid adsorbent A by the heat exchanger 25a for removing the adsorption heat on the adsorber 21 side where the cooling water supplied from the cooling tower or the like flows. The Thereafter, this cycle is repeated. In this way, cold water whose temperature has dropped rapidly can be supplied to the outside from the heat exchange pipe 24a passing through the evaporator 24.

  As described above, the adsorption heat pump requires a heat source to regenerate the adsorbent. As a method of supplying the heat quantity from the heat source to the adsorption tower on the regenerator side, conventionally, exhaust heat generated from a gas turbine cogeneration or a gas engine or the like is recovered with jacket water or a hot water boiler, and the hot water is recovered. A method used as a regeneration heat source is disclosed (for example, see Patent Document 1).

JP 2002-266656 A ([0013] to [0024])

  However, the adsorption heat pump can be driven only by a heat source of 100 ° C. or less, and even if water is used as a refrigerant, the compressor is increased in size and has a high compression ratio as in a conventional compression heat pump. However, as described above, it is necessary to secure a separate heat source such as exhaust heat used in the solid adsorbent regeneration process. When exhaust heat is used as a heat source, it is necessary to separately install equipment such as a hot water boiler, which is complicated on the equipment. In addition, at present, the adsorption heat pump has a problem of low energy efficiency.

  Accordingly, an object of the present invention is to provide an adsorption heat pump that is capable of independent operation without requiring a separate heat source such as exhaust heat and is excellent in energy efficiency.

  In order to solve the above problems, the present invention employs the following configuration.

  That is, two adsorption towers, a condenser, an evaporator, and a flow path through which the refrigerant circulates between these devices, and the one adsorption tower is cooled by a cold heat source and the refrigerant vapor from the evaporator is obtained. And the other adsorption tower is heated by a heating source to desorb the previously adsorbed refrigerant vapor to regenerate the adsorbent in the adsorption tower. A fluid that is used as a regenerator and that condenses the desorbed vapor of the refrigerant from the adsorption tower being regenerated in a condenser, supplies the condensed water to the evaporator, evaporates it, and passes through a flow pipe provided in the evaporator In an adsorption heat pump that exchanges heat with a vapor compressor, a vapor compressor is disposed in a flow path through which the desorption vapor on the exit side of the adsorption tower passes, and the desorption vapor is compressed by this vapor compressor to generate superheated vapor. The superheated steam flow path in the adsorption tower Forming a condenser is the heat generated by condensation of the superheated steam was used as the above heat source.

  In this way, by compressing the desorption steam, it is possible to obtain superheated steam whose temperature has dramatically increased. This superheated steam is passed through the flow path provided in the adsorption tower, and the sensible heat is increased. By releasing the latent heat of condensation at the saturation temperature corresponding to the pressure, a heating source, that is, a heat source is obtained, and the adsorbent can be heated. Thereby, the vapor of the refrigerant adsorbed by the adsorbent can be desorbed and the adsorption tower can be regenerated without using exhaust heat.

  Moreover, since the superheated steam is high in temperature and has excellent desorption ability due to the sensible heat and latent heat of condensation, the heat storage density can be increased, and the cooling or heating ability can be increased. Thereby, energy efficiency is also increased.

  It is desirable to provide a throttle valve and a flash tank for separating the steam generated after expansion from the condensed water between the condenser and the evaporator.

  In this way, the temperature and pressure of the condensed water can be reduced by the throttle valve, and the steam generated after expansion on the outlet side of the throttle valve does not flow into the evaporator. A decrease can be prevented.

  It is desirable to provide a heat exchanger for cooling the condensed water from the condenser between the condenser and the evaporator.

  When the adsorber is in the initial stage of regeneration, the superheated steam compressed by the steam compressor (mechanical booster) becomes almost condensed water at the outlet of the condenser, but as the regeneration proceeds, the dryness of the water vapor after condensation gradually increases. As a result, there arises a problem that the amount of cold heat taken out by the evaporator decreases. As described above, by providing a heat exchanger that allows cooling water to flow between the condenser and the evaporator, an increase in the dryness of water vapor after condensation can be suppressed, and the above problem can be avoided. .

  A heat exchanger for cooling the condensed water from the condenser may be provided between the condenser and the flash tank.

  By providing the heat exchanger, as described above, an increase in dryness of water vapor after condensation can be suppressed, and the above problem can be avoided. As this heat exchanger, a capillary tube having both a throttle valve action and a heat exchanger action may be installed.

  Water can be used as the refrigerant.

  In a conventional compression refrigerator, in order to use water as a refrigerant, a large flow rate due to a low operating pressure and an increase in the size of a compressor due to a high compression ratio are involved. Water can be used as a refrigerant without increasing the size of the apparatus, no special treatment is required for disposal of the refrigerant, and no environmental load is generated.

  As described above, according to the present invention, even if exhaust heat is not used, the desorption steam is converted into superheated steam only by providing a steam compressor in the refrigerant circulation channel, and a heat source is obtained by condensation thereof. The adsorption tower can be regenerated by desorbing the refrigerant vapor from the source. Thereby, it is not necessary to separately arrange a hot water boiler or the like for utilizing the exhaust heat, and the complexity of the facility can be eliminated. Further, since the self-sustaining operation can be performed, the adsorption heat pump can be driven regardless of the installation environment.

  Furthermore, since the superheated steam obtained by compression of the desorption steam is high temperature, it can release condensation latent heat at a saturation temperature corresponding to the increased pressure, and since it has excellent desorption capability, The temperature raising capability can be increased, and the energy efficiency is also increased.

  Embodiments of the present invention will be described below with reference to the accompanying FIGS.

  FIG. 1 shows the configuration of an adsorption heat pump according to the embodiment. This adsorption heat pump includes two adsorption towers 1 and 2 filled with a solid adsorbent A such as silica gel, and the adsorption tower 1, 2 is provided with heat exchange lines 3 and 4 that function as a condenser for condensing refrigerant vapor, and a heat exchange pipe 5a that is formed by providing refrigerant desorption vapor channels, that is, flow pipes 3a and 4a, respectively. The evaporator 5 also serving as a cold water storage tank and flow paths PL1 to PL6 through which the refrigerant circulates between these devices are provided, and valves V1 to V8 for switching the flow of the refrigerant are provided in the flow paths PL1 to PL6. ing. The adsorption towers 1 and 2 are provided with heat exchange lines 6 and 7 including circulation pipes of cooling water supplied from a cooling tower or the like on opposite sides of the heat exchange lines 3 and 4 as an example. The cooling water supplied to the lines 6 and 7 becomes a cooling heat source for each of the adsorption towers 1 and 2.

  A steam compressor 8 (mechanical booster) is provided between the adsorption towers 1 and 2 and the heat exchange lines 3 and 4 to compress the desorbed steam of the refrigerant to generate superheated steam. When this superheated steam is supplied to the heat exchange line 3 or 4 by switching the valves V4 and V8 and the valves V3 and V7, respectively, it becomes a heating source of the adsorption tower 1 or 2, that is, a heat source. A flash tank 9 for separating desorbed steam and condensed water is provided between the heat exchange lines 3 and 4 and the evaporator 5 through valves V2 and V6, respectively. The valve 10 is provided with a valve V9 for releasing steam at the upper side.

  The adsorption towers 1 and 2 are regenerators that desorb the refrigerant vapor previously adsorbed by the other adsorption tower when one of the adsorption towers is used as an adsorber that adsorbs the refrigerant vapor by switching the valves. Used as The operation of the adsorption heat pump when the adsorption tower 1 is used as an adsorber and the adsorption tower 2 is used as a regenerator, that is, when the adsorption tower 1 is in the adsorption process and the adsorption tower 2 is in the regeneration process. explain. In FIG. 1, the valves V1, V6 to V8 are in an open state, and the filled valves V2 to V5 are in a closed state.

  When the refrigerant water comes into contact with the heat exchange pipe 5a disposed in the evaporator 5 and through which cold water passes, the inside of the adsorption heat pump is depressurized in a vacuum state, so that the water evaporates. The evaporated water vapor reaches the adsorption tower 1 through the opened valve V1, and is adsorbed on the solid adsorbent A (for example, silica gel, adsorption density 0.05 kg / kg, filling amount 26 kg per adsorption tower). Is done. The heat of adsorption generated at this time is removed by cooling water (for example, an inlet side temperature of 29 ° C. and an outlet side temperature of 33 ° C.) that passes through the heat exchanger 6, which is a cold heat source, and the temperature rise of the adsorbent is suppressed. Is done. Due to the heat of vaporization of water in the evaporator 5, the cold water in the heat exchange pipe 5 a is rapidly removed and its temperature further decreases.

  On the other hand, the adsorption tower 2 is in the regeneration step, and the water vapor previously adsorbed is desorbed from the solid adsorbent A, and this desorbed water vapor (for example, temperature 40 ° C., pressure 1.0 kPa) is used as the flow path PL4, valve V8 reaches the steam compressor 8 via the flow path PL1 and is compressed to become high-temperature superheated steam (for example, compression ratio 10.0, temperature 300 ° C., pressure 10.0 kPa). This superheated steam is condensed in the heat exchange line 4 through the flow path PL2 and the valve V7, and the sensible heat when the temperature is lowered from the condensation latent heat and the superheated state to the saturated state becomes a heating source, and the adsorbent A Desorption is promoted. This condensed water (for example, temperature 45 ° C., pressure 10.0 kPa) is reduced in temperature and pressure (for example, 7 ° C., 1.0 KPa) through the valve V 6 and the flow path PL 5 and throttled by the throttle valve V 10. It becomes a mixed phase consisting of a small amount of dry saturated steam (for example, dryness of 0.0064) and condensed water. Then, in the flash tank 9, it is separated into water vapor and condensed water, the water vapor is discharged out of the system through the valve V9, the condensed water is returned to the evaporator 5 through the flow path PL6, and the temperature is 5-8 ° C., pressure 0.8 to 1 kPa of water is stored in the evaporator 5.

  FIG. 2 shows a case where the operation state of the adsorption towers 1 and 2 is switched and the adsorption tower 1 is in the regeneration process and the adsorption tower 2 is in the adsorption process. In FIG. 2, valves V2 to V5 are in an open state, and filled valves V1 and V6 to V8 are in a closed state.

  Refrigerant water vapor evaporated by the condensed water flowing from the flash tank 9 in the evaporator 5 in contact with the heat exchange pipe 5a through which the cold water passes reaches the adsorption tower 2 through the opened valve V5, and becomes a solid adsorbent. Adsorbed to A. The heat of adsorption generated at this time is removed by cooling water that passes through the heat exchanger 7, which is a cold heat source, and the temperature rise of the adsorbent is suppressed. Due to the heat of vaporization when the refrigerant evaporates, the cold water in the heat exchange pipe 5a is rapidly removed, and the temperature further decreases.

  On the other hand, in the adsorption tower 1, the desorbed water vapor from the solid adsorbent A reaches the vapor compressor 8 via the flow path PL3, the valve V4, and the flow path PL1, and is compressed to become high-temperature superheated steam. This superheated steam condenses in the heat exchange line 3 through the flow path PL2 and the valve V3, and this condensation latent heat and sensible heat when the temperature drops from the overheated state to the saturated state serve as a heating source to promote desorption. Is done. The condensed water passes through the valve V2 and the flow path PL5, and is reduced in temperature and pressure by the restriction by the throttle valve V10, and becomes a mixed phase composed of a small amount of dry saturated steam and condensed water. Then, it is separated into water vapor and condensed water in the flash tank 9, and the water vapor is discharged out of the system through the valve V9, and the condensed water is returned to the evaporator 5 through the flow path PL3.

  As described above, in the adsorption heat pump, the vapor compressor 8 is disposed in the flow path through which the desorption steam of the refrigerant such as desorption steam passes, and the desorption steam is compressed into superheated steam, and the superheated steam is heat-exchanged. Since the condensed latent heat and the sensible heat of the superheated steam are recovered by passing through the line 3 or 4, a separate heating source (heat source) is not required for desorption of the adsorbent A. Accordingly, it is possible to operate the adsorption heat pump without using a heat source such as exhaust heat, and it is not necessary to separately provide a hot water boiler or the like, and the complexity of the equipment can be eliminated. In addition, the adsorption heat pump can be operated independently regardless of the installation environment. Further, the steam compressor 8 provides high-temperature superheated steam, which is high-temperature, has high sensible heat and latent heat of condensation, and has excellent desorption capability, so that the heat storage density can be increased. Alternatively, the temperature raising ability can be increased. Thereby, energy efficiency is also increased.

  3 and 4 show another embodiment, in which a heat exchange line 4 (when the adsorption tower 2 is in the regeneration process) or a heat exchange line 3 (when the adsorption tower 1 is in the regeneration process) and a flash are shown. A heat exchanger 11 for cooling the condensed water is provided between the tank 9 and the tank 9. Cooling water (for example, an inlet side temperature of 29 ° C. and an outlet side temperature of 33 ° C.) that passes through the heat exchanger 11 passes through the condenser 11 to cool the condensed water from the condenser 4 or 3. The water vapor is separated in the flash tank 9 through 10. When the heat exchanger 11 is provided in this way, as shown in FIG. 3, when the adsorption tower 2 is in the regeneration process, the superheated steam compressed by the steam compressor 8 in the regeneration initial process is converted into the condenser 4. However, as the regeneration proceeds, the degree of dryness of the water vapor after condensation gradually increases, resulting in a problem that the amount of cold heat taken out by the evaporator 5 decreases. For this reason, as described above, by providing the heat exchanger 11 capable of passing cooling water between the condenser 4 and the evaporator 5, it is possible to suppress an increase in the dryness of the water vapor after condensation, and the above problem Can be avoided. The same applies when the adsorption tower 1 shown in FIG. 4 is in the regeneration step. As the heat exchanger 11, a capillary tube having both a throttle valve action and a heat exchanger action may be installed.

  As a preheating source for the regeneration side adsorption tower at the start of adsorption, the high-temperature superheated steam obtained by compressing the water vapor in the evaporator 5 is used by bypassing the suction port of the vapor compressor 8 and the evaporator 5. be able to. As a result, the supply of cold heat is not interrupted when the operation of the adsorption towers 1 and 2 is switched, and cold heat can be continuously supplied.

  The adsorption heat pump according to the present invention does not require exhaust heat and can be operated independently, so that the apparatus is not complicated and is not affected by a large installation environment, and is stable to the process cooling process in the industrial field. It can be used as a cold water supply source.

Explanatory drawing which shows the structure of the adsorption heat pump of embodiment of this invention. Explanatory drawing which shows the structure of the adsorption type heat pump when the flow path of a refrigerant | coolant differs in embodiment shown in FIG. Explanatory drawing which shows the structure of the adsorption heat pump of other embodiment. Explanatory drawing which shows the structure of the adsorption heat pump when the flow path of a refrigerant | coolant differs in embodiment shown in FIG. Explanatory drawing of the adsorption type heat pump of a prior art.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1, 2: Adsorption tower 3, 4: Heat exchange line 3a, 4a: Distribution pipe 5: Evaporator 5a: Heat exchange pipe 6, 7: Heat exchanger 8: Steam compressor 9: Flash tank 10: Throttle valve 11 : Heat exchanger PL1-PL6: Flow path V1-V9: Valve

Claims (5)

Two adsorption towers, a condenser, an evaporator, and a flow path through which the refrigerant circulates between these devices. The one adsorption tower is cooled by a cold heat source and adsorbs the refrigerant vapor from the evaporator. The other adsorption tower is heated by a heating source to desorb the vapor of the refrigerant previously adsorbed to regenerate the adsorbent in the adsorption tower, and the two adsorption towers are alternately adsorber and regenerator. The refrigerant desorbed vapor from the adsorption tower being regenerated is condensed in a condenser, and this condensed water is supplied to the evaporator to evaporate, and the fluid and heat passing through the flow pipe provided in the evaporator are used. In the adsorption heat pump adapted to be exchanged, a vapor compressor is disposed between the adsorption tower and the condenser in the flow path through which the desorption vapor passes, and the condenser is disposed inside the adsorption tower. Condensation latent heat of this desorption vapor is formed by providing each desorption vapor channel. Adsorption heat pump, which comprises using as the heat source. The adsorption heat pump according to claim 1, wherein a throttle valve and a flash tank for separating steam generated after expansion from condensed water are provided between the condenser and the evaporator. The adsorption heat pump according to claim 1, wherein a heat exchanger for cooling the condensed water from the condenser is provided between the condenser and the evaporator. The adsorption heat pump according to claim 2, wherein a heat exchanger for cooling the condensed water from the condenser is provided between the condenser and the flash tank. The adsorption heat pump according to any one of claims 1 to 4, wherein the refrigerant is water.