Energy efficient sorption processes and systems

• US 20030221438A1
• Filed: 02/19/2003
• Published: 12/04/2003
• Est. Priority Date: 02/19/2002
• Status: Abandoned Application

• Current Assignee: Indian Institute of Technology Bombay
• Original Assignee: Indian Institute of Technology Bombay
• Inventors: Agarwal, Akhil, Reddy, S. V. Kota, Bajaj, Jaskaran S., Rane, Milind V.
• Application Number:
  US10/367,982
• Publication Number:
  US 20030221438A1
• Time in Patent Office: Days
• US Class Current: 62/271
• CPC Class Codes: B01D 53/263 by absorption
• CPC Class Codes: F24F 2003/144 by dehumidification only
• CPC Class Codes: F24F 2203/1004 Bearings or driving means
• CPC Class Codes: F24F 3/1417 with liquid hygroscopic desiccants
• CPC Class Codes: F24S 10/95 having evaporator sections and condenser sections, e.g. heat pipes
• CPC Class Codes: F25B 17/08 the absorbent or adsorbent being a solid, e.g. salt F25B17/12 takes precedence
• CPC Class Codes: F25B 2315/005 Regeneration
• CPC Class Codes: F25B 27/007 in sorption type systems
• CPC Class Codes: F25B 27/02 using waste heat, e.g. from internal-combustion engines
• CPC Class Codes: F25B 35/04 using a solid as sorbent
• 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: F28D 15/06 Control arrangements therefor
• CPC Class Codes: Y02A 30/274 using waste energy, e.g. from internal combustion engine
• CPC Class Codes: Y02E 10/40 Solar thermal energy, e.g. solar towers
• CPC Class Codes: Y02E 10/44 Heat exchange systems
• CPC Class Codes: Y02T 10/12 Improving ICE efficiencies

Abstract

The present invention relates to novel energy efficient sorption processes and systems for cooling, dehumidifying and heating using multistage liquid desiccant regenerators, or hybrid cooling systems or adsorption cooling systems involving appropriate combinations of rotating contacting devises, adsorption modules with heat transfer passages in thermal contact with the adsorption module wall and switchable heat pipes. The sorption processes of this invention help in flexible designing of compact cooling, dehumidifing, heating systems easy operability. The adsorption module of this invention leads to lower cycle times as low as 5 minutes; makes it possible to achieve high system Coefficient of Performance (COP) up to 0.9 due to reduced thermal mass; offers high specific cooling power in the range of 50 to 750 W/kg of AC; is easy to manufacture and operates at low costs. The refrigeration cum heating system of this invention with heat pipe in thermal contact with the adsorption modules increase the heat transfer rates without increasing the thermal mass leading to increase of COP and the single or multistage pressure equalisation increases the internal regeneration of heat thereby increasing the COP, reducing the cycle time resulting in increased specific cooling power (SCP), reducing the required quantity of adsorbent/refrigerant making the module compact and cost effective.

Claims

1. Novel energy efficient multi-stage regeneration processes, for regenerating liquid desiccant (LD), using rotating contacting disks assembly to provide intimate contact between LD and vapour/gas to enhance the interfacial area between them for increased heat and/or mass transfer, without problems of carryover of liquid in to the vapour/gas stream or flooding, having the provision to efficiently heat and/or cool the liquid while cooling and dehumidifying the air using a Hybrid Cooling System (HCS).

2. An energy efficient multi-stage regeneration process (EEMSRP) for regenerating liquid desiccant (LD) as claimed in claim 1 further comprising:

Partial or complete regeneration of LD in a Low Temperature Regenerator (LTR)

Partial or complete regeneration of LD in a Intermediate Temperature Regenerator (ITR)

Partial or complete regeneration of LD in a High Temperature Regenerator (HTR)

desuperheating of vapour generated in HTR in a heat exchanger (HTRHE) while preheating the LD before entering HTR

subcooling of LD regenerated in HTR in HTRHE while preheating the LD before entering HTR

condensation of desuperheated vapour from HTRHE in heat exchanger inside ITR while regenerating LD

desuperheating of vapour generated in ITR in a heat exchanger (ITRHE) while preheating the LD before entering ITR and/or HTR

subcooling of LD regenerated in ITR in ITRHE while preheating the LD before entering ITR and/or HTR

subcooling of condensate from ITR in ITRHE while preheating the LD before entering ITR and/or HTR

desuperheating of vapour generated in ITR in a ITRHE while preheating the LD before entering ITR and/or HTR

condensation of desuperheated vapour from ITRHE in “

passages”

thermally in contact with LTR while regenerating LD

flowing of vapour/gas through LTR with the aid of and arrangement such as chimney/fan to pickup the vapours from LD

subcooling of LD regenerated in LTR in LTRHE while preheating the LD before entering LTR and/or ITR and/or HTR

subcooling of condensate from LTR in LTRHE while preheating the LD before entering LTR and/or ITR and/or HTR wherein the number of stages in the regeneration process is (2+n) where n is the number of ITR'"'"'s in the process.

3. The EEMSRP claimed in claim 1 is a two-stage regeneration process involving a HTR and LTR without involvement of ITRs.

4. A two-stage regeneration process claimed in claim 3 comprising:

partial or complete regeneration of LD in a LTR

Partial or complete regeneration of LD in a HTR

desuperheating of vapour generated in HTR in HTRHE while preheating the LD before entering HTR

subcooling of LD regenerated in HTR in HTRHE while preheating the LD before entering HTR

Condensation of desuperheated vapour from HTRHE in “

passages”

thermally in contact with LTR while regenerating LD

Flowing of vapour/gas through LTR with the aid of chimney/fan to pickup the vapours from LD

subcooling of LD regenerated in LTR is in LTRHE while preheating the LD before entering LTR and/or HTR

subcooling of condensate from LTR is also in LTRHE while preheating the LD before entering LTR and/or HTR.

5. A two-stage regeneration process claimed in claim 1 wherein weak LD from the source is pumped and preheated through LTRHE then it is further preheated through HTRHE and partially regenerated in HTR thereafter subcooled in HTRHE before being throttled into LTR where it is fully regenerated and then subcoled in LTRHE and returned to the source.

6. A two-stage regeneration process claimed in claim 1 wherein weak LD from the source is pumped and preheated through LTRHE then partially regenerated in LTR and pumped through HTRHE where it is preheated before entering HTR where it is fully regenerated and then subcoled in HTRHE and LTRHE before being returned to the source.

7. A two-stage regeneration process claimed in claim 1 wherein weak LD from the source is pumped and preheated through LTRHE after which part of the LD flow is throttled into the LTR and fully regenerated and the other part of the LD flow is preheated through HTRHE on its way to HTR where it is fully regenerated and then subcoled in HTRHE before being combined with the fully regenerated LD stream from LTR and then subcooled in LTRHE before being returned to the source.

8. A two-stage regeneration process claimed in claim 1 wherein vapour generated in HTR is desuperheated in HTRHE and the desuper heated vapour is condensed in “

passages”

thermally in contact with LTR and the condensate from LTR is then subcooled in LTRHE

9. The EEMSRP claimed in claim 1 may be a three-stage regeneration process involving a HTR, LTR and one ITR.

10. A three-stage regeneration process claimed in claim 1 wherein weak LD from the source is pumped and preheated through LTRHE and ITRHE then it is further preheated through HTRHE and partially regenerated in HTR thereafter it is subcooled in HTRHE and throttled into the ITR where it is regenerated further and them subcooled in ITRHE before being pumped into LTR where it is fully regenerated and then subcoled in LTRHE and returned to the source.

11. A three-stage regeneration process claimed in claim 1 wherein weak LD from the source is pumped and preheated through LTRHE and partially regenerated in the LTR then pumped through ITRHE where it is preheated before it is regenerated further in ITRHE then this partially regenerated LD is pumped through the HTRHE where it is preheated through HTRHE and regenerated further in HTR thereafter the fully regenerated LD is subcooled in HTRHE, ITRHE and LTRHE and then pumped back to the source.

12. A three-stage regeneration process claimed in claim 1 wherein weak LD from the source is pumped and preheated through LTRHE after which part of the LD flow is throttled into the LTR and fully regenerated and the other part of the LD flow is preheated through ITRHE after which part of the LD flow is throttled into the ITR where it is fully regenerated and the third part of the LD flow is preheated through HTRHE on its way to HTR where it is fully regenerated and then subcoled in HTRHE after which it is combined with the LD flow from the ITR and then subcooled in ITRHE before being combined with the fully regenerated LD stream from LTR and finally it is subcooled in LTRHE before being returned to the source.

13. A three-stage regeneration process claimed in claim 1 wherein vapour generated in HTR is desuperheated in HTRHE and condensed in ITR and further subcooled in ITRHE before throttling it into the desuperheated vapour generated in ITR this liquid vapour stream is then condensed in “

passages”

thermally in contact with LTR and the condensate from LTR is then subcooled in LTRHE before being pumped out.

116. The energy efficient multi-stage regeneration process (EEMSRP) claimed in claim 1 is operated as single stage process wherein there is only a LTR.

14. An energy efficient multi-stage regeneration process (EEMSRP) for regenerating liquid desiccant (LD) comprising:

HTR operating at highest pressure in the system boiling the weak LD absorbing heat from an external source, having insulation on exposed surface to avoid heat loss from LD to surroundings and giving off vapour to next relatively low temperature ITR, in which the latent heat of vapour generated in HTR is used to boil the LD.

ITR operating at a particular pressure heated using the vapour generated in the ITR/HTR operating at next higher-pressure level wherein the vapour generated in the ITR is passed on to the next ITR/LTR operating at next lower pressure level.

A LTR, operating at atmospheric pressure, incorporating large surface density contacting device, having provision to heat the LD, with vapour generated in immediate higher temperature HTR/ITR condensing in the passages, in thermal contact with a container such as a the containing the LTR

Optional arrangement such as a hood with chimney to aid the flow of ambient air through LTR to pickup the moisture from LD.

A device to rotate/oscillate the contacting discs assembly in the LTR

Optional heat exchangers HTRHE, ITRHE and LTRHE used to recycle heat to enhance the energy efficiency of the process

Pressure reducing devices such as throttle valve

Liquid desiccant pump(s)

wherein the number of stages in the system for regeneration is (2+n) where n is the number of ITR'"'"'s in the process.

15. A system for energy efficient single stage regeneration process for regenerating liquid desiccant (LD) as claimed in claim 14 comprising:

LTR, incorporating large surface density contacting device, having provision to heat the LD using heat from an external source in passages which are in thermal contact with a container such as a trough containing the LTR

Optional arrangement such as a hood with chimney to aid the flow of ambient air through LTR to pickup the moisture from LD.

A device to rotate/oscillate the contacting discs assembly in the LTR

Optional heat exchanger used to recycle heat to enhance the energy efficiency of the process

Liquid desiccant pump.

16. Novel contacting device providing intimate contact between fluids to enhance the interfacial area between them comprising:

assembly of contacting discs

shaft for mounting the contacting discs for increased heat and/or mass transfer

device for rotating/oscillating the contacting discs assembly trough to hold fluids in which the disc assembly is partially or fully submerged

passages in thermal contact with a trough

optional device to induce vapour/gas flow optional enclosure with arrangement to guide the flow of vapour/gas.

17. Contacting disc claimed in claim 16 is a mesh, plain/roughened surface or porous material.

18. Contacting disc claimed in claim 16 is of any shape preferably circular.

19. Contacting disc claimed in claim 16 is of any material including metal, plastic, ceramic, alloys, depending on the end use of the device.

20. Contacting disc in the assembly claimed in claim 16 has circular or preferably non-circular hole on the surface for shaft mounting.

21. Contacting disc claimed in claim 16 optionally having lipping.

22. Assembly of contacting discs of similar or dissimilar types as claimed in claim 16 mounted on a solid or hollow shaft of any appropriate material.

23. Contacting discs as claimed in claim 16 having dimples/projections at least on one of its surface functioning as spacers in a disc assembly.

24. The shaft claimed in claim 16 is a rod, tube with or without internal passages for fluid flow.

25. Contacting discs as claimed in claim 16 without dimples/projections mounted with spacers on a shaft.

26. Contacting disc assembly as claimed in claim 16 fixed or thermally bonded to a shaft.

27. Device for rotating/oscillating the contacting discs assembly as claimed in claim 16 capable of rotating the assembly preferably at 3 to 5 rpm or oscillating it through angles greater than 300 in either direction.

29. Heat exchanging passages claimed in claim 16 is a coil, or multiplicity of tubes of any material in thermal britact with the inner or outer surface of the trough or integrated into the trough.

30. Contacting device as claimed in claim 16 without carryover of fluid into the vapour/gas stream or flooding with provision for heating/cooling the liquid depending on the application of the device.

31. Contacting device as claimed in claim 16 with surface density in the range of about 450 to about 600 m²/m³ operating at pressure drop across the contacting device to as low as about 5 Pa.

32. A contact device as claimed in claim 16 with no limit on liquid throughput leading to high efficiency of the process and operating with low power consumption of around 3 to 10 W per 50 to 100 m³/h volume flow rate of vapour/gas.

33. A contact device as claimed in claim 16 in combination with appropriate devices used for applications involving dehumidification, humidification, cooling towers, air-conditioning.

34. A contact device as claimed in claim 16 for applications involving separation of gases from the liquid, regeneration of liquid desiccants, distillation columns, rectification columns, absorption refrigeration systems, multiphase-multicomponent adiabatic/non-adiabatic chemical/bio reactors, and cold/heat storage applications.

35. Contacting device as claimed in claim 16 for humidification or cooling and dehumidification with efficiencies up to 98%.

28. A trough of any material, shape and size to match the assembly of 16.

36. A hybrid cooling system, in which air temperature and humidity are simultaneously controlled, comprising;

An absorber/Indoor Contacting Device (ICD), for dehumidifying air by bringing it in contact with-the LD while being cooled by evaporating refrigerant in the integrated evaporator

A regenerator/Out Door Contacting Device (OCD) for regenerating LD by bringing it in contact with air, while LD being heated by condensing refrigerant in the integrated condenser

A refrigerant compressor, to compress the refrigerant vapour coming from absorber/ICD after absorbing heat from LD and to send the high pressure refrigerant vapour to regenerator/OCD for delivering heat to the LD

A throttling device, for throttling liquid refrigerant moving from regenerator/OCD to absorber/ICD

Optional liquid-liquid heat exchanger, to recycle heat from the hot regenerated strong LD flowing from the regenerator/OCD into the weak LD pumped out of the absorber/ICD

Two optional LD pumps to pump the LD, one from the absorber/ICD to regenerator/OCD and the other from the regenerator/OCD to absorber/ICD

Optional refrigerant liquid to vapour heat exchanger to sub cool the liquid refrigerant coming out of the condenser using the cooling effect of refrigerant vapour coming out of the evaporator

Optional Spiral Contacting Device (SCD) incorporated by the absorber/ICD and regenerator/OCD

Optional external refrigerant evaporator/LD cooler instead of integrated evaporator with absorber/ICD

Optional external refrigerant condenser/LD heater instead of integrated condenser with regenerator/OCD

Optional device to circulate the indoor air through the absorber/ICD and outdoor air through regenerator/OCD and

Optional duct mounting of absorber/ICD and regenerator/OCD.

37. An absorber/ICD claimed in claim 36 is coupled with an evaporator of VCRS.

38. An absorber/ICD claimed in claim 36 is an adiabatic contacting device with a separate heat exchanger to cool the LD.

39. An absorber/ICD and/or regenerator/OCD claimed in claim 36 incorporates large surface density rotating contacting disc assembly as the contacting media between air and LD.

40. An absorber/ICD and/or regenerator/OCD claimed in claim 36, wherein the rotating disc is a mesh, plain/roughened surface or porous material and their like constructed of materials such as a plastic or any other suitable material, which is compatible with LD and air.

41. An absorber/ICD and/or regenerator/OCD claimed in claim 36, wherein the contacting disc assembly is partially submerged in the LD.

43. A contacting disc assembly in the absorber/ICD and/or regenerator/OCD claimed in claim 36 is mounted in a trough or any suitable container constructed of thermal conducting material.

44. A contacting disc assembly in the absorber/ICD and/or regenerator/OCD claimed in claim 36 is mounted in a trough or any suitable container constructed of non conducting material with wall thickness of <

0.2 mm and to withstand the pressure of the heat transfer fluid.

45. An absorber/ICD and/or regenerator/OCD claimed in claim 36, optionally incorporates SCD as the contacting media between the LD and air.

46. A SCD in the absorber/ICD and/or regenerator/OCD claimed in claim 36, is a mesh, plain/roughened surface or porous material and their like constructed of material such as plastic or any other suitable material which is compatible with LD and air.

47. A SCD in the absorber/ICD and/or regenerator/OCD claimed in claim 45 is partially submerged in the LD.

48. A SCD in the absorber/ICD and/or regenerator/OCD claimed in claim 45 is rotated at low rpm in the LD, preferably at around 3 to 5 rpm or oscillated to an angle greater than 30°

in either direction.

49. A SCD in the absorber/ICD and/or regenerator/OCD claimed in claim 36 is mounted in a trough or any suitable container without passages.

50. A trough claimed in claim 49 constructed of conducting/non conducting material without limitation of wall thickness.

51. An absorber/ICD claimed in claim 36 comprises passages wherein the evaporation of the refrigerant takes place, are in thermal contact with the trough of absorber/ICD.

52. Passages of the absorber/ICD claimed in claim 51 are inside or outside or integrated into the trough of absorber/ICD.

53. Passages of the absorber/ICD claimed in claim 52, wherein the chilled fluid is flowing through the passages instead of evaporating the refrigerant.

54. A regenerator/OCD claimed in claim 36, comprises the passages wherein the condensation of the refrigerant takes place, are in thermal contact with the trough of the regenerator/OCD.

55. Passages of the regenerator/OCD claimed in claim 54 is inside or outside or integrated into the trough of the regenerator/OCD.

56. Passages of the regenerator/OCD claimed in claim 55, where in a hot fluid is flowing through the passages instead of condensing refrigerant.

57. The circulating device in the absorber/ICD and/or regenerator as claimed in claim 36, is forced/induced draft fan.

58. The liquid-liquid heat exchanger claimed in claim 36 is made of alternate material such as plastic or any other suitable material compatible with LD.

59. A regenerator/OCD claimed in claim 36 is coupled with a condenser of conventional VCRS.

60. A regenerator/OCD claimed in claim 36 is an adiabatic contacting device with a separate heat exchanger to heat the LD.

61. The optional device as claimed in claim 36, to circulate air through the regenerator/OCD is a chimney.

62. A hybrid cooling system as claimed in claim 36, wherein the elevation difference between the regenerator/OCD and the absorber/ICD is not sufficient, two LD pumps are used to pump the LD, one from the absorber/ICD to regenerator/OCD and the other from the regenerator/OCD to absorber/ICD.

63. A hybrid cooling system as claimed in claim 36, wherein the regenerator/OCD is placed at higher elevation than the absorber/ICD with the LD flowing from regenerator/OCD to absorber/ICD by gravity.

64. A hybrid cooling system as claimed in claim 36, wherein the regenerator/OCD is at a higher elevation than the absorber/ICD, one LD pump is used to pump the LD from the absorber/ICD to regenerator/OCD.

65. A hybrid cooling system as claimed in claim 36, wherein the absorber/ICD is placed at higher elevation than the regenerator/OCD with LD flowing from absorber/ICD to regenerator/OCD by gravity.

66. A hybrid cooling system as in claim 36, wherein the absorber/ICD is at a higher elevation than the regenerator/OCD, one LD pump is used to pump the LD from the absorber/ICD to regenerator/OCD.

67. A hybrid cooling system as in claim 36, wherein the said VCRS is replaced by Vapour Absorption/Adsorption System.

68. Hybrid cooling system as claimed in claim 36, wherein

the pressure ratio across the compressor is reduced up to 36%

cooling effect produced is increased up to 60%

COP increased up to 45%

as compared to VCRS for air conditioning and refrigeration applications involving cooling and/or dehumidification/drying.

42. A contacting disc assembly absorber/ICD and regenerator/OCD as claimed in 39 is rotated at low rpm in the LD, preferably at around 3 to 5 rpm or oscillated to an angle greater than 30°

in either direction.

69. An adsorption module comprising:

a. a main containment vessel

b. plurality of passages of cross sections that are in thermal contact or integrated into the wall of the containment vessel

c. adsorbent filled in the containment vessel

70. The adsorption module as in claim 69, wherein the cross-section of the containment vessel is circular, square, rectangular, elliptical or any other shape.

71. The adsorption module as claimed in claim 69, wherein the material of construction of the containment vessel is selected from materials such as metals, composite materials preferably with high thermal conductivity of at least 1 W/m.K and being compatible with heat transfer fluids.

72. An adsorption module as claimed in claim 69 wherein the cross section of the passages is circular, square, rectangular, elliptical or any other shape.

73. An adsorption module as claimed in claim 69 wherein the passages are open at both ends allowing through flow of heat transfer fluids.

74. An adsorption module as claimed in claim 69 wherein the number of passages is varied as per the desired rate of heat transfer and fin effectiveness of the module wall.

75. An adsorption module as claimed in claim 69 wherein the containment vessel shell is co-extruded with the passages.

76. An adsorption module as in claim 69 wherein the passages are in thermal contact with the inner surface of the containment vessel wall of the module.

77. An adsorption module as claimed in claim 69 wherein the passages are in thermal contact with the partition(s) in the containment vessel of the module.

78. The adsorption module as in claim 69 wherein the passages run partially along the length of the module.

79. An adsorption module as claimed in claim 69 wherein the passages are optionally non linear.

80. An adsorption module as claimed in claim 69 wherein the sorbents include activated carbon (AC), calcium chloride, magnesium chloride, stronsium chloride, zeolite, silica gel and there like.

81. An adsorption module as claimed in claim 69 wherein the adsorbate include ammonia, methanol, water and alcohols.

82. An adsorption module as claimed in claim 69 wherein the heating is optionally effected by a “

non-flow”

heat sources such as solar/electric heater and there like.

83. An adsorption module as claimed in claim 69 wherein the “

passages”

for supplying heat to the module is not necessary when the module directly receives heat through the containment vessel wall and the “

passages”

are only required to ensure removal of heat from the module.

84. An adsorption module as claimed in claim 69 wherein the “

passages”

for removal of heat from the module is not necessary when the module directly loses heat through the containment vessel wall and the “

passages”

are only required to ensure supply of heat to the module.

85. An adsorption module as claimed in claim 69 wherein the passages are closed at one end to function as a heat pipe.

114. An adsorption module as claimed in claim 69 that

leads to lower cycle times as low as 5 minutes

makes it possible to achieve high system Coefficient of Performance (COP) up to 0.9 due to reduced thermal mass

offers high specific cooling power in the range of 50 to 750 W/kg of AC

is easy to manufacture and operation and costs less.

86. Switchable heat pipes comprising.

evaporator

condenser

optional squeezable tube

optional pincher and

means to actuate pincher and/or to displace condenser.

87. Switchable heat pipes as claimed in claim 86 wherein squeezable tube is used to actuate or isolate the heat pipes.

88. Switchable heat pipes as claimed in claim 86 used to transfer heat from a single source to multiple receivers in desired sequence.

89. Switchable heat pipe as claimed in claim 86 used to transfer heat from multiple sources to a single receiver in desired sequence.

90. Switchable heat pipes as claimed in claim 88 wherein tilting of the condenser is used to actuate, control or isolate the heat pipes.

91. Switchable heat pipes as claimed in claim 86 wherein evaporator and condenser forms a continuous “

passage”

capable of bending enabling control of heat transfer rate and maximum operating temperature of the heat pipe.

92. Switchable heat pipes as claimed in claim 86 wherein heat pipe cross-section is of any shape.

93. Switchable heat pipes as claimed in claim 86 wherein cross section of condenser and evaporator is matched or mismatched.

94. Switchable heat pipes as claimed in claim 86 wherein the material of construction of heat pipe is of any material based on the end use.

95. Switchabe heat pipes as claimed in claim 86, wherein a wick is optionally provided on the inner wall of the evaporator, condenser and squeezable tubing to facilitate the draining back of the fluid.

96. The wick claimed in claim 95 for use in the squeezable tube is selected from material that is also squeezable.

97. Switchable heat pipes as claimed in claim 86 wherein during the adsorption phase when the module needs to be cooled, the cooling heat pipe with its evaporator integrated with the module would be operative, while the heating heat pipe whose evaporator is integrated with the module would be switched off.

98. Switchable heat pipes as claimed in claim 86 wherein means is provided for the isolation of heat pipes where, heat transfer rate is to be varied while exchanging heat between fix temperature source and sink by varying the number of active heat.

99. Switchable heat pipes as claimed in claim 86 capable of being used in refrigeration, airconditioning, waste heat recovery, solar collectors and any application involving heat transfer.

100. A refrigeration cum heating system working on an adsorption refrigeration cycle comprising:

plurality of adsorption modules wherein a plurality of “

passages”

are in thermal contact with the walls of the containment vessels, so that containment vessel wall acts as fin

“

passages”

, in thermal contact with the walls of the containment vessel wall act as heat pipes, used for transferring the heat to/from the module

heat recovery tank/heat sink, wherein heat release from the module during the adsorption phase is collected to provide optional hot utility

evaporator

condenser

means for actuating or isolating heat pipes and

heat source such as solar energy, waste heat sources, direct fuel firing.

101. A refrigeration cum heating system as claimed in claim 100 capable of operating with or without hot utility generation.

102. The adsorption module as claimed in claim 100, wherein.

cross-sectional shape of the module is varied based on peak pressures in module and space constraint

number of “

passages”

for transferring heat to and from the module is varied on the basis of desired capacity of heat pipe,

the “

passages”

either for heating or cooling is/are optionally eliminated

the material of construction for the module and passages is preferably metallic with high thermal conductivity above 10 W/m.K

the “

passages”

are in thermal contact with the wall of the main cylinder constructed by co-extrusion, welding, thermal paste or any suitable means.

103. “

Passages”

of claim 100 are of variable cross-sectional shape and size based on the desired capacity of heat transfer and space constraints.

104. “

Passages”

of claim 100 are optionally switchable heat pipe(s).

105. Switchable heat pipe(s) claimed in claim 100 optionally uses a pinchable flexible tubing with pinching device for isolating the heat receiving and the heat giving sections.

106. Flexible tube, used in the heat pipes claimed in claim 104 to connect the heat receiving and the heat giving sections, is made of any pinchable/squeezable material that are compatible with the working fluid.

107. A refrigeration system as claimed in claim 100 wherein the number of adsorption modules is varied as per the desired cooling capacity of the system.

108. An adsorption system claimed in claim 100 is optionally operable with adsorption refrigeration cycle with single and multistage pressure equalization for heat regeneration in the adsorption module increasing COP and reducing cycle time.

109. A refrigeration system claimed in claim 100 wherein heat is transferred from heat source to the module and from module to the heat recovery tank/heat sink by means of a switchable heat pipe.

110. A refrigeration system claimed in claim 100 wherein refrigerant is transferred from adsorption module to the condenser and then to the evaporator by simple tube, during generation phase and then returned back by same tube during adsorption phase.

111. A refrigeration system claimed in claim 100 wherein a valve may optionally be used to connect two or more modules for single/multi-stage pressure equalization.

112. A control system used for controlling the flow of heat to and from the adsorption module and flow of refrigerant of claim 100, wherein multiple control is operable using a single control shaft with appropriate cams.

113. The shaft as claimed in claim 101 is operable by a single low rpm motor in the range of 0.2-0.013 rpm.

115. A refrigeration cum heating system as claimed in claim 100 wherein

The heat pipe in thermal contact with the adsorption modules increase the heat transfer rates without increasing the thermal mass leading to increase of COP

The single or multistage pressure equalisation increases the internal regeneration of heat thereby increasing the COP, reducing the cycle time resulting in increased specific cooling power (SCP), reducing the required quantity of adsorbent/refrigerant making the module compact and cost effective.