Energy efficient sorption processes and systems

• US 20050262720A1
• Filed: 07/14/2005
• Published: 12/01/2005
• Est. Priority Date: 02/19/2002
• Status: Abandoned Application

• Current Assignee: Indian Institute of Technology Delhi
• Original Assignee: Indian Institute of Technology Delhi
• Inventors: Agarwal, Akhil, Kota Reddy, S. V., Bajaj, Jaskaran S., Rane, Milind V.
• Application Number:
  US11/180,650
• Publication Number:
  US 20050262720A1
• Time in Patent Office: Days
• US Class Current: 34/330
• 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

1-116. -116. (canceled)

117. A multi-stage regeneration system for regenerating a liquid desiccant, comprising (1) the liquid desiccant, (2) a vapour/gas stream, (3) a high temperature regenerator and (4) a low temperature regenerator comprising a rotating contacting device assembly that provides contact between the liquid desiccant and the vapour/gas stream for heat and/or mass transfer between the liquid desiccant and the vapour/gas stream without substantial carryover of the liquid desiccant into the vapour/gas stream, wherein the rotating contacting device picks up the liquid desiccant, brings the liquid desiccant that was picked up into contact with the vapour/gas stream and then releases the liquid desiccant that was picked up from the rotating contacting device.

118. The system of claim 117, further comprising an intermediate temperature regenerator.

119. The system of claim 117, further comprising a low temperature heat exchanger and a high temperature heat exchanger.

120. The system of claim 119, further comprising an intermediate temperature heat exchanger.

121. The system of claim 119, further comprising a throttle, wherein the liquid desiccant is pumped and preheated through the low temperature heat exchanger, then the liquid desiccant is further preheated through the high temperature heat exchanger and partially regenerated in the high temperature regenerator, and thereafter the liquid desiccant is cooled in the high temperature heat exchanger and transferred through the throttle into the low temperature regenerator where the liquid desiccant is further regenerated and then cooled in the low temperature heat exchanger.

122. The system of claim 119, wherein the liquid desiccant is pumped and preheated through the low temperature heat exchanger, then partially regenerated in the low temperature regenerator and pumped through the high temperature heat exchanger where the liquid desiccant is preheated before entering the high temperature regenerator where the liquid desiccant is regenerated and then cooled in the high and low temperature heat exchangers.

123. The system of claim 119, wherein the liquid desiccant is pumped and preheated through the low temperature heat exchanger, then a part of the liquid desiccant is transferred through the throttle in to the low temperature regenerator and regenerated and the other part of the liquid desiccant is preheated through the high temperature heat exchanger and regenerated in the high temperature regenerator, and thereafter cooled in the high temperature heat exchanger before being combined with the liquid desiccant of low temperature regenerator and then cooled in the low temperature heat exchanger.

124. The system of claim 119, wherein a vapour generated in the high temperature regenerator is desuperheated in the high temperature heat exchanger and condensed in a passage thermally in contact with the low temperature regenerator and a condensate is cooled in the low temperature heat exchanger.

125. The system of claim 117, wherein the high temperature regenerator comprises a heat source.

126. The system of claim 117, wherein the rotating contacting device comprises an assembly of contacting discs mounted on a shaft.