Heat exchanger, heat pump, dehumidifier, and dehumidifying method

• US 6,442,951 B1
• Filed: 04/20/2001
• Issued: 09/03/2002
• Est. Priority Date: 06/30/1998
• Status: Expired due to Fees

• Current Assignee: Ebara Corporation
• Original Assignee: Ebara Corporation
• Inventors: Fukasaku, Yoshiro, Maeda, Kensaku
• Primary Examiner(s): DOERRLER, WILLIAM CHARLES
• Application Number:
  US09/720,877
• Time in Patent Office: 501 Days
• Field of Search: 62/93, 62/94, 622/71, 625/13, 623/31
• US Class Current: 62/94
• CPC Class Codes: F24F 2203/021 Compression cycle
• CPC Class Codes: F24F 2203/1004 Bearings or driving means
• CPC Class Codes: F24F 2203/1012 Details of the casing or cover
• CPC Class Codes: F24F 2203/1016 combined with another type of cooling principle, e.g. compression cycle
• CPC Class Codes: F24F 2203/1028 combined with a spraying device
• CPC Class Codes: F24F 2203/1032 Desiccant wheel
• CPC Class Codes: F24F 2203/104 Heat exchanger wheel
• CPC Class Codes: F24F 2203/1048 Geometric details
• CPC Class Codes: F24F 2203/1056 comprising a reheater
• CPC Class Codes: F24F 2203/1068 comprising one rotor
• CPC Class Codes: F24F 2203/1084 comprising two flow rotor segments
• CPC Class Codes: F24F 3/1423 with a moving bed of solid desiccants, e.g. a rotary wheel supporting solid desiccants
• CPC Class Codes: F24F 5/001 Compression cycle type
• CPC Class Codes: F28D 15/02 in which the medium condenses and evaporates, e.g. heat pipes heat pipes used in solar heat collectors F24S10/95; in radiators F28D1/0226; in nuclear reactors G21C15/257
• CPC Class Codes: F28D 15/0266 with separate evaporating and condensing chambers connected by at least one conduit; Loop-type heat pipes; with multiple or common evaporating or condensing chambers F28D15/043 takes precedence
• CPC Class Codes: F28D 15/0275 Arrangements for coupling heat-pipes together or with other structures, e.g. with base blocks; Heat pipe cores
• CPC Class Codes: F28F 1/24 and extending transversely F28F1/38 takes precedence

Abstract

A heat exchanger of a high heat exchange efficiency with a small size for its large heat exchanger duty is provided. The heat exchanger comprises: a first compartment 310 for flowing a first fluid A; a second compartment 320 for flowing a second fluid B; a first flow passage 251 passing through the compartment and for flowing the third fluid for exchanging heat with the first fluid A; and a second flow passage 252 passing through the compartment and for flowing the third fluid for exchanging heat with the first fluid B; the first and second flow passages 251, 252 are formed as an integral passage; the third fluid flows through from the first flow passage 251 to the second flow passage 252; the third fluid evaporates in the first flow passage 251 at a specific pressure; the third fluid condenses in the second flow passage 252 at the approximately specific pressure. Since the third fluid flows from the first flow passage to the second flow passage, heat transfer from the first compartment to the second compartment is allowed. High heat transfer coefficient is achieved due to evaporating heat transfer or condensing heat transfer.

Claims

1. A heat exchanger comprising:

a first compartment for a first fluid flowing therethrough;

a second compartment for a second fluid flowing therethrough;

a first flow passage passing through the first compartment and for a third fluid flowing therethrough, the third fluid exchanging heat with the first fluid; and

a second flow passage passing through the second compartment and for the third fluid flowing therethrough, the third fluid exchanging heat with the second fluid;

wherein the first and second flow passages are formed as an integral passage;

the third fluid flows through from the first flow passage to the second flow passage, and the third fluid evaporates on a heat transfer surface located at a flow passage side of the first flow passage at a specific pressure, the flow passage side being for the third fluid flowing therein, and condenses on a heat transfer surface located at a flow passage side of the second flow passage at approximately the same pressure as the specific pressure, the flow passage side being for the third fluid flowing therein.

2. A heat exchanger as recited in claim 1, wherein the second fluid flowing through the second compartment is caused to contain water.

3. A heat exchanger as recited in claim 1, further comprising a third flow passage passing through the second compartment and disposed parallel to the second flow passage for the third fluid flowing threrethrough, the third fluid exchanging heat with the second fluid, wherein the third fluid substantially bypasses the first compartment and is supplied to the third flow passage.

4. A heat exchanger as recited in claim 3, wherein the third fluid mainly in liquid phase is supplied to the first flow passage, and the third fluid mainly in vapor phase is supplied to the third flow passage.

5. A heat exchanger comprising:

a first compartment for a first fluid flowing therethrough;

a second compartment for a second fluid flowing therethrough;

first flow passages passing through the first compartment and for a third fluid flowing therethrough, the third fluid exchanging heat with the first fluid; and

second flow passages passing through the second compartment and for the third fluid flowing therethrough, the third fluid exchanging heat with the second fluid;

wherein the third fluid flows through from the first flow passage to the second flow passage, the third fluid evaporates on the heat transfer surfaces located on the flow passage side of the first flow passages at specific pressures and condenses on the heat transfer surfaces located on the flow passage side of the second flow passages at approximately the same pressures as the specific pressures;

the first flow passages are provided in a plurality; and

the specific pressures in the plurality of flow passages are different from each other.

6. A heat pump comprising a heat exchanger including:

a first compartment for a first fluid flowing therethrough;

a second compartment for a second fluid flowing therethrough;

a first flow passage passing through the first compartment and for a third fluid flowing therethrough, the third fluid exchanging heat with the first fluid; and

a second flow passage passing through the second compartment and for the third fluid flowing therethrough, the third fluid exchanging heat with the second fluid;

wherein the first and second flow passages are formed as an integral passage;

the third fluid flows through from the first flow passage to the second flow passage, and the third fluid evaporates on a heat transfer surface located at a flow passage side of the first flow passage at a specific pressure, the flow passage side being for the third fluid flowing therein, and condenses on a heat transfer surface located at a flow passage side of the second flow passage at approximately the same pressure as the specific pressure, the flow passage side being for the third fluid flowing therein;

a pressure raiser for raising the pressure of the third fluid in vapor phase;

a first heat exchanger for taking heat from the third fluid in vapor phase, the third fluid in vapor phase having been boosted with the pressure raiser, with a high temperature fluid, thus causing the third fluid in vapor phase to condense under a first pressure;

a first throttle for reducing the third fluid in pressure, the third fluid having been condensed with the first heat exchanger, to the specific pressure and for leading the third fluid to the first flow passage;

a second throttle for reducing the third fluid in pressure, the third fluid having been condensed at the specific pressure, to a third pressure; and

a third heat exchanger for evaporating the third fluid, the third fluid having been reduced in pressure with the second throttle, by imparting heat to the third fluid from a low temperature fluid under the third pressure.

7. A heat pump comprising a heat exchanger including:

a first compartment for a first fluid flowing therethrough;

a second compartment for a second fluid flowing therethrough;

a first flow passage passing through the first compartment and for a third fluid flowing therethrough, the third fluid exchanging heat with the first fluid; and

a second flow passage passing through the second compartment and for the third fluid flowing therethrough, the third fluid exchanging heat with the second fluid;

wherein the first and second flow passages are formed as an integral passage;

the third fluid flows through from the first flow passage to the second flow passage, and the third fluid evaporates on a heat transfer surface located at a flow passage side of the first flow passage at a specific pressure, the flow passage side being for the third fluid flowing therein, and condenses on a heat transfer surface located at a flow passage side of the second flow passage at approximately the same pressure as the specific pressure, the flow passage side being for the third fluid flowing therein

a compressor for compressing the pressure of the third fluid in vapor phase;

a first heat exchanger for taking heat from the third fluid in vapor phase, the third fluid in vapor phase having been compressed with the compressor, with a high temperature fluid, thus causing the third fluid in vapor phase to condense under a first pressure;

a first throttle for reducing the third fluid in pressure, the third fluid having been condensed with the first heat exchanger, to the specific pressure and for leading the third fluid to the first flow passage;

a second throttle for reducing the third fluid in pressure, the third fluid having been condensed at the specific pressure, to a third pressure; and

a third heat exchanger for evaporating the third fluid, the third fluid having been reduced in pressure with the second throttle, by imparting heat to the third fluid from a low temperature fluid under the third pressure.

8. A dehumidifier comprising;

the heat pump as recited in claim 7; and

a moisture adsorber having a desiccant for adsorbing moisture in the first fluid;

wherein the heat exchanger is disposed on the downstream side of the first fluid flow relative to the moisture adsorber, so as to cool the first fluid from which moisture is adsorbed by the desiccant.

9. A heat pump comprising;

a pressure raiser for raising the pressure of a refrigerant;

a first heat exchanger for condensing the refrigerant, the refrigerant having been boosted with the pressure raiser, by taking heat from the refrigerant with a high temperature fluid under a first pressure;

a first throttle for reducing the refrigerant in pressure, the refrigerant having been condensed with the first heat exchanger, to a second pressure;

a second heat exchanger for evaporating the refrigerant, the refrigerant having been reduced in pressure with the first throttle, by the heat from the first fluid under the second pressure, and for condensing the refrigerant, after the evaporation, by taking heat from the refrigerant with a second fluid;

a second throttle for reducing the refrigerant in pressure, after being condensed with the second heat exchanger, to a third pressure; and

a third heat exchanger for evaporating the refrigerant, the refrigerant having been reduced in pressure with the second throttle, by imparting heat to the refrigerant from low temperature fluid under the third pressure.

10. A heat pump comprising;

a compressor for compressing a refrigerant;

a first heat exchanger for condensing the refrigerant, the refrigerant having been compressed with the compressor, by taking heat from the refrigerant with a high temperature fluid under a first pressure;

a first throttle for reducing the refrigerant in pressure, the refrigerant having been condensed with the first heat exchanger, to a second pressure;

a second heat exchanger for evaporating the refrigerant, the refrigerant having been reduced in pressure with the first throttle, by the heat from the first fluid under the second pressure, and for condensing the refrigerant, after the evaporation, by taking heat from the refrigerant with a second fluid;

a second throttle for reducing the refrigerant in pressure, after being condensed with the second heat exchanger, to a third pressure; and

a third heat exchanger for evaporating the refrigerant, the refrigerant having been reduced in pressure with the second throttle, by imparting heat to the refrigerant from low temperature fluid under the third pressure.

11. A heat pump as recited in claim 10:

wherein the second heat exchanger comprises;

a first compartment for the first fluid flowing therethrough,

a second compartment for the second fluid flowing therethrough,

a first flow passage passing through the first compartment and for the refrigerant flowing therethrough, the refrigerant exchanging heat with the first fluid, and

a second flow passage passing through the second compartment and for the refrigerant flowing therethrough, the refrigerant exchanging heat with the second fluid;

wherein the refrigerant flows through from the first flow passage to the second flow passage, the refrigerant evaporates under the second pressure on the heat transfer surface located on the flow passage side of the first flow passage, and condenses approximately under the second pressure on the heat transfer surface located on the flow passage side of the second flow passage.

12. A heat pump as recited in claim 10, comprising:

a vapor-liquid separator disposed between the first throttle and the second heat exchanger so as to separate the refrigerant, that has been reduced in pressure to the second pressure, into refrigerant liquid and refrigerant vapor.

13. A heat pump as recited in claim 11, comprising:

a vapor-liquid separator disposed between the first throttle and the second heat exchanger so as to separate the refrigerant, the refrigerant having been reduced in pressure to the second pressure, into refrigerant liquid and refrigerant vapor; and

a third flow passage disposed parallel to the second flow passage;

wherein the refrigerant liquid separated with the vapor-liquid separator is caused to flow to the first flow passage, and the refrigerant vapor separated with the vapor-liquid separator is caused to bypass the first flow passage and to flow to the third flow passage.

14. A heat pump as recited in claim 10:

wherein the second heat exchanger comprises;

a first compartment for the first fluid flowing therethrough;

a second compartment for the second fluid flowing therethrough;

first flow passages passing through the first compartment and for the refrigerant flowing therethrough, the refrigerant exchanging heat with the first fluid; and

second flow passages passing through the second compartment and for the refrigerant flowing therethrough, the refrigerant exchanging heat with the second fluid;

wherein the refrigerant flows through from the first flow passages to the second flow passages;

the refrigerant evaporates under the second pressure on the heat transfer surfaces located on the flow passage side of the first flow passages, and condenses approximately under the second pressure on the heat transfer surfaces located on the flow passage side of the second flow passages;

the first flow passages are provided in a plurality; and

the second pressures in the plurality of flow passages are different from each other.

15. A dehumidifier comprising:

the heat pump as recited in claim 10; and

a moisture adsorber having a desiccant for adsorbing moisture in the low temperature fluid;

wherein the second heat exchanger is disposed on the downstream side of the low temperature fluid flow relative to the moisture adsorber, so as to cool the low temperature fluid, from which moisture has been adsorbed with the desiccant, and before low temperature fluid causes the refrigerant to evaporate with the third heat exchanger.

16. A dehumidifier comprising:

a moisture adsorber having a desiccant for adsorbing moisture in the process air; and

a process air cooler, disposed on the downstream side of the process air flow relative to the moisture adsorber, for cooling the process air from which moisture has been adsorbed with the desiccant;

wherein the process air cooler cools the process air by the evaporation of a refrigerant, the evaporation being at a specific pressure,

wherein all of the refrigerant is forced to flow generally in one direction and the process air cooler condenses the evaporated refrigerant at approximately the same pressure as the specific pressure in the process air cooler, cooled with a cooling fluid.

17. A method of dehumidifying process air, comprising:

a first step of cooling the process air with a refrigerant that evaporates at a low pressure;

a second step of raising the pressure of the refrigerant, that has evaporated in the first step, to a high pressure;

a third step of heating regeneration air for regenerating a desiccant with the refrigerant that condenses at the high pressure;

a fourth step of regenerating the desiccant by desorbing moisture from the desiccant with the regeneration air heated in the third step;

a fifth step of adsorbing moisture in the process air with the desiccant regenerated in the fourth step;

a sixth step of cooling the process air, from which moisture has been removed by adsorption in the fifth step, by evaporating the refrigerant, that has condensed in the third step, at an intermediate pressure between the low pressure and the high pressure; and

a seventh step of condensing the refrigerant, that has evaporated at the intermediate pressure, at a pressure which is approximately the same as the intermediate pressure.

18. A dehumidifier comprising:

a first refrigerant-air heat exchanger having a first refrigerant inlet-outlet port and a second refrigerant inlet-outlet port, and for causing heat exchange between a refrigerant and a process air;

a compressor having an intake port and a discharge port for taking in and discharging the refrigerant, with the second refrigerant inlet-outlet port being disposed to be selectively connectable to either the intake port or the discharge port;

a second refrigerant-air heat exchanger having a third refrigerant inlet-outlet port and a fourth refrigerant inlet-outlet port, and for causing heat exchange between the refrigerant and the process air, with either the intake port or the discharge port, that has not been connected to the second refrigerant inlet-outlet port, being disposed to be connectable to the third refrigerant inlet-outlet port;

a third refrigerant-air heat exchanger, disposed on the upstream side of the process air flow flowing through the first refrigerant-air heat exchanger, having a fifth refrigerant inlet-outlet port and a sixth refrigerant inlet-outlet port, and for causing heat exchange among the refrigerant, the process air, and a cooling fluid, with the fourth refrigerant inlet-outlet port being disposed to be selectively connectable to either the fifth refrigerant inlet-outlet port or a sixth refrigerant inlet-outlet port, and

a moisture adsorber disposed on the upstream side of the process air flow passing through the third refrigerant-air heat exchanger and having a desiccant for adsorbing moisture in the process air,

wherein;

either the fifth refrigerant inlet-outlet port or the sixth refrigerant inlet-outlet port that has not been connected to the fourth refrigerant inlet-outlet port is connected to the first refrigerant inlet-outlet port, and

the third refrigerant-air heat exchanger cools the process air passing through the third refrigerant-air heat exchanger by the evaporation of the refrigerant supplied from the fourth refrigerant inlet-outlet port to the fifth refrigerant inlet-outlet port when the fourth refrigerant inlet-outlet port and the fifth refrigerant inlet-outlet port are interconnected, and cools and condenses the evaporated refrigerant with the cooling fluid, so that the condensed refrigerant can be supplied to the first refrigerant-air heat exchanger.

19. A dehumidifier as recited in claim 18, further comprising:

a first switching mechanism for switching the selective connecting relation of the intake and discharge ports of the compressor to the second and the third refrigerant inlet-outlet ports; and

a second switching mechanism for switching the selective connecting relation of the fifth and the sixth refrigerant inlet-outlet ports to the fourth and the first refrigerant inlet-outlet ports.

21. A dehumidifier as recited in claim 18;

wherein the regeneration air is passed through the second refrigerant-air heat exchanger and the moisture adsorber, the desiccant being regenerated with the regeneration air, is disposed on the downstream side of the regeneration air flow relative to the second refrigerant-air heat exchanger; and

further comprising;

a sensible heat exchanger, disposed on the upstream side of the regeneration air relative to the second refrigerant-air heat exchanger, for causing heat exchange between the regeneration air that has passed through the moisture adsorber and the regeneration air before exchanging heat in the second refrigerant-air heat exchanger; and

a switching mechanism for switching the sensible heat exchanger between operative and inoperative states.

20. A dehumidifier comprising:

a first refrigerant-air heat exchanger having a first refrigerant inlet-outlet port and a second refrigerant inlet-outlet port, and for causing heat exchange between a refrigerant and a process air;

a compressor having an intake port and a discharge port for taking in and discharging the refrigerant, with the second refrigerant inlet-outlet port being disposed to be selectively connectable to either the intake port or the discharge port;

a second refrigerant-air heat exchanger having a third refrigerant inlet-outlet port and a fourth refrigerant inlet-outlet port, and for causing heat exchange between the refrigerant and the process air, with either the intake port or the discharge port, that has not been connected to the second refrigerant inlet-outlet port, being disposed to be connectable to the third refrigerant inlet-outlet port;

a third refrigerant-air heat exchanger, disposed on the upstream side of the process air flow flowing through the first refrigerant-air heat exchanger, having a fifth refrigerant inlet-outlet port and a sixth refrigerant inlet-outlet port, and for causing heat exchange among the refrigerant, the process air, and a cooling fluid, with the fourth refrigerant inlet-outlet port being disposed to be selectively connectable to either the fifth refrigerant inlet-outlet port or a sixth refrigerant inlet-outlet port, and

a moisture adsorber disposed on the upstream side of the process air flow passing through the third refrigerant-air heat exchanger and having a desiccant for adsorbing moisture in the process air,

wherein;

either the fifth refrigerant inlet-outlet port or the sixth refrigerant inlet-outlet port that has not been connected to the fourth refrigerant inlet-outlet port is connected to the first refrigerant inlet-outlet port,

the third refrigerant-air heat exchanger cools the process air passing through the third refrigerant-air heat exchanger by the evaporation of the refrigerant supplied from the fourth refrigerant inlet-outlet port to the fifth refrigerant inlet-outlet port when the fourth refrigerant inlet-outlet port and the fifth refrigerant inlet-outlet port are interconnected, and cools and condenses the evaporated refrigerant with the cooling fluid, so that the condensed refrigerant can be supplied to the first refrigerant-air heat exchanger

a first switching mechanism for switching the selective connecting relation of the intake and discharge ports of the compressor to the second and the third refrigerant inlet-outlet ports;

a second switching mechanism for switching the selective connecting relation of the fifth and the sixth refrigerant inlet-outlet ports to the fourth and the first refrigerant inlet-outlet ports

an expansion valve disposed in the refrigerant passage between the sixth refrigerant inlet-outlet port and the second switching mechanism, the expansion valve having a first temperature sensor and a second temperature sensor,

wherein the first temperature sensor is disposed in the refrigerant passage between the second refrigerant inlet-outlet port and the first switching mechanism, and the second temperature sensor is disposed in the refrigerant passage between the first switching mechanism and the third refrigerant inlet-outlet port, and the first and the second temperature sensors can be selectively switched.

22. A dehumidifier comprising:

a first refrigerant-air heat exchanger having a first refrigerant inlet-outlet port and a second refrigerant inlet-outlet port, and for causing heat exchange between a refrigerant and a process air;

a compressor having an intake port and a discharge port for taking in and discharging the refrigerant, with the second refrigerant inlet-outlet port being disposed to be selectively connectable to either the intake port or the discharge port;

a second refrigerant-air heat exchanger having a third refrigerant inlet-outlet port and a fourth refrigerant inlet-outlet port, and for causing heat exchange between the refrigerant and the process air, with either the intake port or the discharge port, that has not been connected to the second refrigerant inlet-outlet port, being disposed to be connectable to the third refrigerant inlet-outlet port;

a third refrigerant-air heat exchanger, disposed on the upstream side of the process air flow flowing through the first refrigerant-air heat exchanger, having a fifth refrigerant inlet-outlet port and a sixth refrigerant inlet-outlet port, and for causing heat exchange among the refrigerant, the process air, and a cooling fluid, with the fourth refrigerant inlet-outlet port being disposed to be selectively connectable to either the fifth refrigerant inlet-outlet port or a sixth refrigerant inlet-outlet port, and

a moisture adsorber disposed on the upstream side of the process air flow passing through the third refrigerant-air heat exchanger and having a desiccant for adsorbing moisture in the process air,

wherein;

either the fifth refrigerant inlet-outlet port or the sixth refrigerant inlet-outlet port that has not been connected to the fourth refrigerant inlet-outlet port is connected to the first refrigerant inlet-outlet port,

the third refrigerant-air heat exchanger cools the process air passing through the third refrigerant-air heat exchanger by the evaporation of the refrigerant supplied from the fourth refrigerant inlet-outlet port to the fifth refrigerant inlet-outlet port when the fourth refrigerant inlet-outlet port and the fifth refrigerant inlet-outlet port are interconnected, and cools and condenses the evaporated refrigerant with the cooling fluid, so that the condensed refrigerant can be supplied to the first refrigerant-air heat exchanger,

wherein air is used as the cooling fluid, and liquid state water is supplied together with the air before condensing the refrigerant in the third refrigerant-air heat exchanger.

23. An operation method of a dehumidifier including

a first refrigerant-air heat exchanger having a first refrigerant inlet-outlet port and a second refrigerant inlet-outlet port, and for causing heat exchange between a refrigerant and a process air;

a compressor having an intake port and a discharge port for taking in and discharging the refrigerant, with the second refrigerant inlet-outlet port being disposed to be selectively connectable to either the intake port or the discharge port;

a second refrigerant-air heat exchanger having a third refrigerant inlet-outlet port and a fourth refrigerant inlet-outlet port, and for causing heat exchange between the refrigerant and the process air, with either the intake port or the discharge port, that has not been connected to the second refrigerant inlet-outlet port, being disposed to be connectable to the third refrigerant inlet-outlet port;

a third refrigerant-air heat exchanger, disposed on the upstream side of the process air flow flowing through the first refrigerant-air heat exchanger, having a fifth refrigerant inlet-outlet port and a sixth refrigerant inlet-outlet port, and for causing heat exchange among the refrigerant, the process air, and a cooling fluid, with the fourth refrigerant inlet-outlet port being disposed to be selectively connectable to either the fifth refrigerant inlet-outlet port or a sixth refrigerant inlet-outlet port, and

a moisture adsorber disposed on the upstream side of the process air flow passing through the third refrigerant-air heat exchanger and having a desiccant for adsorbing moisture in the process air,

wherein;

either the fifth refrigerant inlet-outlet port or the sixth refrigerant inlet-outlet port that has not been connected to the fourth refrigerant inlet-outlet port is connected to the first refrigerant inlet-outlet port,

the third refrigerant-air heat exchanger cools the process air passing through the third refrigerant-air heat exchanger by the evaporation of the refrigerant supplied from the fourth refrigerant inlet-outlet port to the fifth refrigerant inlet-outlet port when the fourth refrigerant inlet-outlet outlet port and the fifth refrigerant inlet-outlet port are interconnected, and cools and condenses the evaporated refrigerant with the cooling fluid, so that the condensed refrigerant can be supplied to the first refrigerant-air heat exchanger,

said method comprising the steps of;

interconnecting, in the cooling operation mode, the second refrigerant inlet-outlet port and the intake port, the discharge port and the third refrigerant inlet-outlet port, the fourth refrigerant inlet-outlet port and the fifth refrigerant inlet-outlet port, and the sixth refrigerant inlet-outlet port and the first refrigerant inlet-outlet port, respectively;

interconnecting, in the heating mode, the second refrigerant inlet-outlet port and the discharge port, the intake port and the third refrigerant inlet-outlet port, the fourth refrigerant inlet-outlet port and the sixth refrigerant inlet-outlet port, and the fifth refrigerant inlet-outlet port and the first refrigerant inlet-outlet port, respectively; and

setting the third refrigerant-air heat exchanger at inoperative state.

24. An operation method as recited in claim 23, further comprising a step of interconnecting, in the defrosting mode, the second refrigerant inlet-outlet port and the intake port, the discharge port and the third refrigerant inlet-outlet port, the fourth refrigerant inlet-outlet port and the sixth refrigerant inlet-outlet port, and the fifth refrigerant inlet-outlet port and the first refrigerant inlet-outlet port, respectively.

25. A dehumidifier comprising:

a moisture adsorber having a desiccant for adsorbing moisture in the process air; and

a process air cooler for cooling the process air from which moisture has been removed by adsorption with the desiccant;

wherein the process air cooler has a construction of cooling the process air by the evaporation of the refrigerant, and the evaporated refrigerant is cooled and condensed with a cooling fluid at substantially the same pressure as the evaporating pressure; and

the process air cooler has a plurality of evaporation pressures of the refrigerant for cooling the process air and a plurality of condensation pressures of the refrigerant cooled and condensed with the cooling fluid corresponding to the evaporation pressures, the plurality of evaporation pressures being different from each other.

26. A dehumidifier as recited in claim 25, comprising:

an evaporator for further cooling the process air, the process air having been cooled with the process air cooler, by evaporating the refrigerant condensed with the process air cooler;

a compressor for compressing the refrigerant vaporized by evaporation with the evaporator; and

a condenser for cooling and condensing the refrigerant, the refrigerant having been compressed with the compressor, with the regeneration air;

wherein, the refrigerant having been condensed with the condenser is supplied to the process air cooler.

27. A dehumidifier as recited in claim 25:

wherein air is used as the cooling fluid, and the air, after having condensed the refrigerant in the process air cooler, is led as the regeneration air for regenerating the desiccant, to the moisture adsorber.

28. A dehumidifier comprising:

a moisture adsorber having a desiccant adsorbing moisture from the process air and being regenerated with the regeneration air;

a heat pump, having a compressor for compressing a refrigerant, for pumping up heat from a low temperature heat source to a high temperature heat source using the process air as the low temperature heat source and the regeneration air as the high temperature heat source; and

a process air cooler, disposed on the downstream side of the process air flow relative to the moisture adsorber, for cooling the process air from which moisture has been removed by adsorption with the desiccant;

wherein the refrigerant before being taken into the compressor is heated by the refrigerant after being compressed with the compressor subsequently exchanging heat with the regeneration air before regenerating the desiccant, and

the process air cooler has a construction of cooling the process air by the evaporation of the refrigerant, and of cooling to condense the refrigerant with a cooling fluid at substantially the same pressure as the evaporating pressure.

29. A dehumidifier as recited in claim 28, comprising:

an evaporator for further cooling the process air, the process air having been cooled with the process air cooler, by evaporating the refrigerant, the refrigerant having been condensed with the process air cooler; and

a condenser for cooling to condense the refrigerant, the refrigerant having been compressed with the compressor;

wherein the refrigerant having been condensed with the condenser is supplied to the process air cooler.

30. A dehumidifier as recited in claim 29, wherein the regeneration air, before flowing into the condenser, is used as the cooling fluid.

31. A dehumidifier comprising:

a moisture adsorber having a desiccant adsorbing moisture from the process air and being regenerated with the regeneration air;

a heat pump, having a compressor for compressing a refrigerant, for pumping up heat from a low temperature heat source to a high temperature heat source using the process air as the low temperature heat source and the regeneration air as the high temperature heat source; and

a process air cooler, disposed on the downstream side of the process air flow relative to the moisture adsorber, for cooling the process air from which moisture has been removed by adsorption with the desiccant;

wherein the refrigerant before being taken into the compressor is heated by the refrigerant after being compressed with the compressor subsequently exchanging heat with the regeneration air before regenerating the desiccant, and

the process air cooler has a construction of cooling the process air by the evaporation of the refrigerant, and of cooling to condense the refrigerant with a cooling fluid,

wherein the process air cooler has a construction such that air is used as the cooling fluid, and liquid state water is supplied together with the air.

32. A dehumidifier comprising:

a moisture adsorber having a desiccant for adsorbing moisture in process air, with the adsorbed moisture being desorbed with regeneration air;

a first heat pump for pumping up heat from a first evaporation temperature to a first condensation temperature by circulating a refrigerant, the first heat pump evaporating the refrigerant at a first intermediate temperature between the first evaporation temperature and the first condensation temperature, followed by condensing the refrigerant at a temperature that is approximately equal to the first intermediate temperature; and

a second heat pump for pumping up heat from a second evaporation temperature which is lower than the first evaporation temperature to a second condensation temperature which is lower than the first condensation temperature by circulating a refrigerant, the second heat pump evaporating the refrigerant at a second intermediate temperature between the second evaporation temperature and the second condensation temperature, followed by condensing the refrigerant at a temperature that is approximately equal to the second intermediate temperature;

wherein the process air from which moisture has been removed by adsorption with the desiccant is first cooled with the refrigerant that evaporates at either the first intermediate temperature or the second intermediate temperature whichever higher, then cooled with the refrigerant that evaporates at the lower intermediate temperature, then cooled with the refrigerant that evaporates at the first evaporation temperature, then cooled with the refrigerant that evaporates at the second evaporation temperature;

the regeneration air is heated with the refrigerant that condenses at either a temperature that is approximately equal to the first intermediate temperature or a temperature that is approximately equal to the second intermediate temperature, whichever is lower, then heated with the refrigerant that condenses at the higher temperature, then heated with a refrigerant that condenses at the second condensation temperature, then heated with a refrigerant that condenses at the first condensation temperature, and then the moisture is removed from the desiccant by desorption with the heated regeneration air.

33. A dehumidifier comprising:

a moisture adsorber having a desiccant for adsorbing moisture in process air, the moisture being desorbed with regeneration air;

a process air cooler, disposed on the downstream side of the process air flow relative to the moisture adsorber, for cooling the process air;

a first condenser for heating the regeneration air by condensing a refrigerant at a first condensing pressure; and

a second condenser for heating the regeneration air by condensing a refrigerant at a second condensing pressure which is lower than the first condensing pressure;

wherein the process air cooler has a construction of cooling the process air by the evaporation of the refrigerant, and of cooling to condense the evaporated refrigerant with the regeneration air before removing moisture from the desiccant in the moisture adsorber;

the second condenser and the first condenser are disposed in that order in the passage from the regeneration air between the process air cooler and the moisture adsorber;

the process air cooler has, as evaporation pressures of the refrigerant for cooling the process air, a first intermediate pressure which is lower than the first condensation pressure and a second intermediate pressure which is lower than the first intermediate pressure;

the process air cooler has a construction of cooling the refrigerant with the regeneration air to condense the refrigerant at approximately the first intermediate pressure and at approximately the second intermediate pressure;

the process air cooler has a construction of cooling the process air with the refrigerant that evaporates at the second intermediate pressure after the regeneration air is cooled with the refrigerant that evaporates at the first evaporation pressure, and heating the regeneration air with the refrigerant that condenses approximately at the first intermediate pressure, after heating the regeneration air is heated with the refrigerant that condenses approximately at the second intermediate pressure; and

the refrigerant condensed with the first condenser is supplied so as to be evaporated at either one of the first or the second intermediate pressures, and the refrigerant condensed with the second condenser is supplied so as to be evaporated at the other one of the first or the second intermediate pressures.

34. A dehumidifier as recited in claim 33, further comprising:

a first evaporator, disposed on the downstream side of the process air coming from the process air cooler, for cooling the process air by evaporating the refrigerant at a first evaporation pressure which is lower than the first intermediate pressure;

a second evaporator, disposed on the downstream side of the process air coming from the first evaporator, for cooling the process air by evaporating the refrigerant at a second evaporation pressure which is lower than the first evaporation pressure;

a first compressor for compressing the refrigerant evaporated with the first evaporator and sending the refrigerant to the first condenser; and

a second compressor for compressing the refrigerant evaporated with the second evaporator and supplying the refrigerant to the second condenser.

35. A dehumdifier comprising:

a moisture adsorber having a desiccant for adsorbing moisture in process air, the moisture being desorbed with regeneration air;

a process air cooler, disposed on the downstream side of the process air flow relative to the moisture adsorber, for cooling the process air;

a first condenser for heating the regeneration air by condensing a refrigerant at a first condensing pressure; and

a second condenser for heating the regeneration air by condensing a refrigerant at a second condensing pressure which is lower than the first condensing pressure;

wherein the process air cooler has a construction of cooling the process air by the evaporation of the refrigerant, and of cooling to condense the evaporated refrigerant with the regeneration air before removing moisture from the desiccant in the moisture adsorber;

the second condenser and the first condenser are disposed in that order in the passage from the regeneration air between the process air cooler and the moisture adsorber;

the process air cooler has, as evaporation pressures of the refrigerant for cooling the process air, a first intermediate pressure which is lower than the first condensation pressure and a second intermediate pressure which is lower than the first intermediate pressure;

the process air cooler has a construction of cooling the refrigerant with the regeneration air to condense the refrigerant at approximately the first intermediate pressure and at approximately the second intermediate pressure;

the process air cooler has a construction of cooling the process air with the refrigerant that evaporates at the second intermediate pressure after the regeneration air is cooled with the refrigerant that evaporates at the first evaporation pressure, and heating the regeneration air with the refrigerant that condenses approximately at the first intermediate pressure, after heating the regeneration air is heated with the refrigerant that condenses approximately at the second intermediate pressure; and

the refrigerant condensed with the first condenser is supplied so as to be evaporated at either one of the first or the second intermediate pressures, and the refrigerant condensed with the second condenser is supplied so as to be evaporated at the other one of the first or the second intermediate pressures,

wherein the first intermediate pressure further includes a plurality of pressures.

36. A dehumidifier comprising

a moisture adsorber having a desiccant for adsorbing moisture in process air, the moisture being desorbed with regeneration air;

a process air cooler, disposed on the downstream side of the process air flow relative to the moisture adsorber, for cooling the process air;

a first condenser for heating the regeneration air by condensing a refrigerant at a first condensing pressure; and

a second condenser for heating the regeneration air by condensing a refrigerant at a second condensing pressure which is lower than the first condensing pressure;

wherein the process air cooler has a construction of cooling the process air by the evaporation of the refrigerant, and of cooling to condense the evaporated refrigerant with the regeneration air before removing moisture from the desiccant in the moisture adsorber;

the second condenser and the first condenser are disposed in that order in the passage from the regeneration air between the process air cooler and the moisture adsorber;

the process air cooler has, as evaporation pressures of the refrigerant for cooling the process air, a first intermediate pressure which is lower than the first condensation pressure and a second intermediate pressure which is lower than the first intermediate pressure;

the process air cooler has a construction of cooling the refrigerant with the regeneration air to condense the refrigerant at approximately the first intermediate pressure and at approximately the second intermediate pressure;

the process air cooler has a construction of cooling the process air with the refrigerant that evaporates at the second intermediate pressure after the regeneration air is cooled with the refrigerant that evaporates at the first evaporation pressure, and heating the regeneration air with the refrigerant that condenses approximately at the first intermediate pressure, after heating the regeneration air is heated with the refrigerant that condenses approximately at the second intermediate pressure; and

the refrigerant condensed with the first condenser is supplied so as to be evaporated at either one of the first or the second intermediate pressures, and the refrigerant condensed with the second condenser is supplied so as to be evaporated at the other one of the first or the second intermediate pressures,

wherein the first and the second condensers are positioned vertically above the process air cooler.

37. A dehumidifier comprising

a first air flow passage having a first intake port at its one end and a first discharge port at the other end, for flowing first air from the first intake port toward the first discharge port;

a second air flow passage having a second intake port at its one end and a second discharge port at the other end, for flowing regeneration air from the second intake port toward the second discharge port;

a desiccant wheel, having a desiccant for the process air to pass through, with its rotation axis directed vertically; and

a third heat exchanger for cooling the process air, wherein the desiccant removes moisture from the process air before being cooled by the third heat exchanger; and

wherein the first air passage mainly includes a downward flow passage portion directed vertically downward and an upward flow passage portion directed vertically upward; and

wherein moisture of the desiccant is removed by the regeneration air, and the second air flow passage mainly includes a flow passage portion directed vertically upward.

38. A dehumidifier as recited in claim 37, comprising:

a first heat exchanger for heating the regeneration air; and

a heat pump having a high temperature heat source and a low temperature heat source;

wherein the third heat exchanger constitutes the low temperature heat source, and the first heat exchanger constitutes the high temperature heat source.

39. A dehumidifier comprising:

a process air blower for blowing process air;

a regeneration air blower for blowing regeneration air;

a compressor for compressing a refrigerant;

a refrigerant condenser for heating the regeneration air by condensing the compressed refrigerant;

a refrigerant evaporator for cooling the process air by evaporating the refrigerant condensed with the refrigerant condenser; and

a desiccant wheel, having a desiccant which is regenerated by the regeneration air heated with the refrigerant condenser as the regeneration air passes through the desiccant and which processes the process air as the process air passes through the desiccant;

wherein the process air blower, the regeneration air blower, and the compressor are positioned vertically below the desiccant wheel, and

the refrigerant condenser is positioned vertically above the desiccant wheel.

40. A dehumidifier as recited in claim 39, wherein the process air is cooled with the refrigerant evaporator after being processed with the desiccant, and the refrigerant evaporator is positioned vertically above the desiccant wheel.