Enhanced lithium bromide absorption cycle water vapor recompression absorber

• US 5,816,070 A
• Filed: 11/25/1996
• Issued: 10/06/1998
• Est. Priority Date: 04/24/1995
• Status: Expired due to Term

• Current Assignee: Milton Meckler
• Original Assignee: Milton Meckler
• Inventors: Meckler, Milton
• Primary Examiner(s): DOERRLER, WILLIAM CHARLES
• Application Number:
  US08/756,216
• Time in Patent Office: 680 Days
• Field of Search: 62/476, 62/485, 62/101, 62/109, 62/484, 62/486
• US Class Current: 62/476
• CPC Class Codes: F25B 15/008 with multi-stage operation F25B15/006 takes precedence
• CPC Class Codes: F25B 15/06 the refrigerant being water vapour evaporated from a salt solution, e.g. lithium bromide F25B15/025 takes precedence
• CPC Class Codes: Y02A 30/27 Relating to heating, ventilation or air conditioning [HVAC] technologies
• CPC Class Codes: Y02B 30/62 Absorption based systems

Abstract

A Vapor Recompression Absorber (VRA) for reprocessing a concentrated solution of water refrigerant and Lithium-Bromide salt from at least one solution concentrator in a closed chiller system, the VRA being comprised of an upper heat-in absorption chamber and a lower heat-out evaporation chamber and sump separated by a thin polymer heat transfer wall, strong solution from the system applied as a falling film to the heat-in side is recirculated, while strong solution applied as a falling film to the heat-out side and evaporation therefrom transported by a vapor compressor to the absorption chamber and condensed for recirculation, the sump solution being being strengthened and delivered to and evaporated in the absorber of the chiller system for maximized chilling of a water distribution system.

Claims

1. A water vapor recompression absorber in a closed absorption chiller system comprised of at least one concentrator to which heat is applied to vaporize a water refrigerant and to concentrate an absorbent solution of said water refrigerant and a sorbent material, having compressor means for cooling and liquifying said vaporized water refrigerant, having an evaporator means for chilling said water refrigerant by means of evaporation, there being a heat-in coil from warmer system water that is chilled thereby and which discharges heat to vaporize said water refrigerant, having an absorber for condensing the vaporized refrigerant and for its absorption into the absorbent solution, there being a heat-out coil to pick up and discharge the heat of vaporization and the heat of dilution from the system, and pump means for returning the absorbent solution to the at least one concentrator for recycling through said closed system, the water vapor recompression absorber including, an upper vapor absorption chamber and a lower vapor evaporation chamber, there being a vertically disposed heat transfer wall between and separating the two chambers, pressure means for discharging strong absorbent solution from the system concentrator and onto a heat-in side of the heat transfer wall exposed into the absorption chamber, collection means for recirculating weakened solution from the heat-in side of the heat transfer wall and to the system concentrator, vapor compressor means for transporting refrigerant vapor from the evaporation chamber and into the absorption chamber at increased pressure while lowering vapor pressure in the evaporation chamber, there being a sump open from the evaporation chamber for collection of strong solution, pump means for discharging the strong solution from the sump and onto the heat-out side of the heat transfer wall exposed to the evaporation chamber, and a strong absorbent solution line from the sump discharging into the absorber of the chiller system,

whereby the chilling effect applied to the heat-in coil of the chiller system is maximized.

2. The vapor recompression absorber and chiller system as set forth in claim 1, wherein the absorbent material is a Lithium-Bromide (liBr) salt.

3. The vapor recompression absorber and chiller system as set forth in claim 1, wherein the upper absorption chamber, the lower vapor evaporation chamber and the sump open from the evaporation chamber are all incorporated within a common tank.

4. The vapor recompression absorber and chiller system as set forth in claim 3, wherein said two chambers are separated by a multiplicity of panels forming said heat transfer wall.

5. The vapor recompression absorber and chiller system as set forth in claim 3, wherein said two chambers are separated by a concentric assembly of ring-shaped panels forming said heat transfer wall interconnected by top and bottom headers with spaces between said adjacent pairs of panels and alternately open into the upper and lower chambers.

6. The vapor recompression absorber and chiller system as set forth in claim 5, wherein the collection means for recirculating weakened solution is connected to said bottom headers by a manifold for said recirculation of solution to the system concentrator.

7. The vapor recompression absorber and chiller system as set forth in claim 1, wherein the heat transfer wall is a panel of polymer material.

8. The vapor recompression absorber and chiller system as set forth in claim 1, wherein the heat transfer wall is a thin membrane of polymer material.

9. The vapor recompression absorber and chiller system as set forth in claim 1, wherein the heat transfer wall is a polymer membrane of a thickness ranging from 0.02 to 0.04 mm.

10. The vapor recompression absorber and chiller system as set forth in claim 1, wherein the means for discharging solution onto the heat-in and heat-out sides of the heat transfer wall are weir means, the solutions being applied to the sides of the wall as falling films.

11. The vapor recompression absorber and chiller system as set forth in claim 1, wherein the vapor compressor means is a low pressure blower open from the evaporation chamber and into the absorption chamber.

12. The vapor recompression absorber and chiller system as set forth in claim 11, wherein the vapor compressor means blower operates at a pressure on the order of 3 to 6 inches water gage.

13. A water vapor recompression absorber in a closed system for increasing the chilling capacity of a double effect reverse flow absorption chiller comprised of a first stage high temperature concentrator to which heat is applied to vaporize a water refrigerant and to concentrate a strong absorbent solution of said water refrigerant and a sorbent material , having a high temperature heat exchanger in a return line of weakened absorbent solution to said first stage concentrator and transferring heat of a strengthened absorbent solution concentrated by said first stage concentrator and into said return line of weakened absorbent solution, having a second stage concentrator with a condenser vapor chamber and sump for cooling and liquifying said vaporized water refrigerant, having an evaporator with a vapor chamber for chilling said water refrigerant by means of evaporation, having a low temperature heat exchanger in a line of the second stage absorbent solution joined by the first stage absorbent solution and transferring heat therefrom and into a return line of weakened absorbent solution and discharging into said evaporator vapor chamber, there being a heat-in coil from warmer system water that is chilled in said evaporator vapor chamber and which discharges heat to vaporize said water refrigerant, having an absorber for reducing water vapor pressure and with a vapor chamber and sump for water vapor absorption into the absorbent solution, there being a first heat-out coil in the absorber vapor chamber to pick up and discharge the heat of dilution, there being a second heat-out coil in the second stage concentrator and in series with said first heat-out coil to pick up and discharge the heat of condensation from the first stage concentrator, and pump means for returning the absorbent solution from the absorber sump and through said return line and to the first stage concentrator for recycling through said closed system,

the water vapor recompression absorber including, an upper vapor absorption chamber and a lower vapor evaporation chamber, there being a vertically disposed heat transfer wall between and separating the two chambers, pressure means for discharging strong absorbent solution from the first stage high temperature concentrator and into a heat-in side of the heat transfer wall exposed into the absorption chamber, collection means for recirculating weakened solution from the heat-in side of the heat transfer wall and to the first stage concentrator, vapor compressor means for transporting refrigerant vapor from the evaporation chamber and into the absorption chamber at increased pressure while lowering vapor pressure in the evaporation chamber, there being a sump open from the evaporation chamber for collection of strong solution, pump means for discharging the strong solution from the sump and onto the heat-out side of the heat transfer wall exposed to the evaporation chamber, and a strong absorbent solution line from the sump and through the low temperature heat exchanger and discharging into the absorber of the chiller system,

whereby the chilling effect applied to the heat-in coil of the chiller system is maximized.

14. The vapor recompression absorber and chiller system as set forth in claim 13, wherein the absorbent material is a Lithium-Bromide (LiBr) salt.

15. The vapor recompression absorber and chiller system as set forth in claim 13, wherein the upper absorption chamber, the lower vapor evaporation chamber and the sump open from the evaporation chamber are all incorporated within a common tank.

16. The vapor recompression absorber and chiller system as set forth in claim 13, wherein said two chambers are separated by a multiplicity of panels forming said heat transfer wall.

17. The vapor recompression absorber and chiller system as set forth in claim 15, wherein said two chambers are separated by a concentric assembly of ring-shaped panels forming said heat transfer wall interconnected by top and bottom headers with spaces between said adjacent pairs of panels and alternately open into the upper and lower chambers.

18. The vapor recompression absorber and chiller system as set forth in claim 17, wherein the collection means for recirculating weakened solution is connected to said bottom headers by a manifold for said recirculation of solution to the first stage concentrator.

19. The vapor recompression absorber and chiller system as set forth in claim 13, wherein the heat transfer wall is a panel of polymer material.

20. The vapor recompression absorber and chiller system as set forth in claim 13, wherein the heat transfer wall is a thin membrane of polymer material.

21. The vapor recompression absorber and chiller system as set forth in claim 13, wherein the heat transfer wall is a polymer membrane of a thickness ranging from 0.02 to 0.04 mm.

22. The vapor recompression absorber and chiller system as set forth in claim 13, wherein the means for discharging solution onto the heat-in and heat-out sides of the heat transfer wall are weir means, the solutions being applied to the sides of the wall as falling films.

23. The vapor recompression absorber and chiller system as set forth in claim 17, wherein the vapor compressor means is a low pressure blower open from the evaporation chamber and into the absorption chamber.

24. The vapor recompression absorber and chiller system as set forth in claim 23, wherein the vapor compressor means blower operates at a pressure on the order of 3 to 6 inches water gage.

25. A water vapor recompression absorber in a closed system for increasing the chilling capacity of a double effect series flow absorption chiller comprised of a first stage high temperature concentrator to which heat is applied to vaporize a water refrigerant and to concentrate strong absorbent solution of said water refrigerant and a sorbent material, having a high temperature heat exchanger in a return line of weakened absorbent solution to said first stage concentrator and transferring heat of a strengthened absorbent solution concentrated by said first stage concentrator and into said return line of weakened absorbent, having a second stage concentrator with a condenser vapor chamber and sump for cooling and liquifying said vaporized water refrigerant, having an evaporator with a vapor chamber for chilling said water refrigerant by means of evaporation , having a low temperature heat exchanger in a series line of the second stage absorbent solution and transferring heat therefrom and into a return line of weakened absorbent solution in a series line through said high temperature heat exchanger, there being a heat-in coil from warmer system water that is chilled in said evaporator vapor chamber and which discharges heat to vaporize said water refrigerant having an absorber for reducing water vapor pressure and with a vapor chamber and sump for water vapor absorption into the absorbent solution, there being a first heat-out coil in the absorber vapor chamber to pick up and discharge the heat of dilution, there being a second heat-out coil in the second stage concentrator and in series with said first heat-out coil to pick up and discharge the heat of condensation from the first stage concentrator, and pump means for returning the absorbent solution from the absorber sump and through said return line in series through the low and high temperature heat exchangers and to the first stage concentrator for recycling through said closed system, the water vapor recompression absorber including, an upper vapor absorption chamber and a lower vapor evaporation chamber, there being a vertically disposed heat transfer wall between and separating the two chambers, pressure means for discharging strong absorbent solution from the first stage high temperature concentrator and onto a heat-in side of the heat transfer wall exposed into the absorption chamber, collection means for recirculating weakened solution from the heat-in side of the heat transfer wall and to the first stage concentrator, vapor compressor means for transporting refrigerant vapor from the evaporation chamber and into the absorption chamber at increased pressure while lowering vapor pressure in the evaporation chamber, there being a sump open from the evaporation chamber for collection of strong solution, pump means for discharging the strong solution from the sump and onto the heat-out side of the heat transfer wall exposed to the evaporation chamber, and a strong absorbent solution line from the sump and through the low temperature heat exchanger and discharging into the absorber of the chiller system,

whereby the chilling effect applied to the heat-in coil of the chiller system is maximized.

26. The vapor recompression absorber and chiller system as set forth in claim 25, wherein the absorbent material is a Lithium-Bromide (LiBr) salt.

27. The vapor recompression absorber and chiller system as set forth in claim 25, wherein the upper absorption chamber, the lower vapor evaporation chamber and the sump open from the evaporation chamber are all incorporated within a common tank.

28. The vapor recompression absorber and chiller system as set forth in claim 27, wherein said two chambers are separated by a multiplicity of panels forming said heat transfer wall.

29. The vapor recompression absorber and chiller system as set forth in claim 27, wherein said two chambers are separated by a concentric assembly of ring-shaped panels forming said heat transfer wall interconnected by top and bottom headers with spaces between said adjacent pairs of panels and alternately open into the upper and lower chambers.

30. The vapor recompression absorber and chiller system as set forth in claim 29, wherein the collection means for recirculating weakened solution is connected to said bottom headers by a manifold for said recirculation of solution to the high temperature concentrator.

31. The vaper recompression absorber and chiller system as set forth in claim 25, wherein the heat transfer wall is a panel of polymer material.

32. The vapor recompression absorber and chiller system as set forth in claim 25, wherein the heat transfer wall is a thin membrane of polymer material.

33. The vapor recompression absorber and chiller system as set forth in claim 25, wherein the heat transfer wall is a polymer membrane of a thickness ranging from 0.02 to 0.04 mm.

34. The vapor recompression absorber and chiller system as set forth in claim 25, wherein the means for discharging solution onto the heat-in and heat-out sides of the heat transfer wall are weir means, the solutions being applied to the sides of the wall as falling films.

35. The vapor recompression absorber and chiller system as set forth in claim 25, wherein the vapor compressor means is a low pressure blower open from the evaporation chamber and into the absorption chamber.

36. The vapor recompression absorber and chiller system as set forth in claim 35, wherein the vapor compressor means blower operates at a pressure on the order of 3 to 6 inches water age.

37. A water vapor recompression absorber in a closed system for increasing the chilling capacity of a double effect parallel flow absorption chiller comprised of a first stage high temperature concentrator to which heat is applied to vaporize a water refrigerant and to concentrate a strong absorbent solution of said water refrigerant and a sorbent material, having a high temperature heat exchanger in a return line of weakened absorbent solution to said first stage concentrator and transferring heat of a strengthened absorbent solution concentrated by by said first stage concentrator and into said return line of weakened absorbent solution, having a second stage concentrator with a condenser vapor chamber and sump for cooling and liquifying said vaporized water refrigerant, having an evaporator with a vapor chamber for chilling said water refrigerant by means of evaporation, having a low temperature heat exchanger in a parallel line of the second stage absorbent solution joined by a first stage absorbent solution and transferring heat therefrom and into the return line of weakened absorbent solution, there being a heat-in coil from warmer system water that is chilled in said evaporator vapor chamber, and which discharges heat to vaporize said water refrigerant, having an absorber for reducing water vapor pressure and with a vapor chamber and sump for water vapor absorption into the absorbent solution, there being a first heat-out coil in the absorber vapor chamber to pick up and discharge the heat of dilution, there being a second heat-out coil in the second stage concentrator and in series with said first heat-out coil to pick up and discharge the heat of condensation from the first stage concentrator, and pump means for returning the absorbent solution from the absorber sump and through said return line in series through the low and high temperature heat exchangers and to the first stage concentrator for recycling through said closed system,

the water vapor recompression absorber including, an upper vapor absorption chamber and a lower vapor evaporation chamber, there being a vertically disposed heat transfer wall between and separating the two chambers, pressure means for discharging strong absorbent solution from the first stage high temperature concentrator and onto a heat-in side of the heat transfer wall exposed into the absorption chamber, collection means for recirculating weakened solution from the heat-in side of the heat transfer wall and to the first stage concentrator, vapor compressor means for transporting refrigerant vapor from the evaporation chamber and into the absorption chamber at increased pressure while lowering vapor pressure in the evaporation chamber, there being a sump open from the evaporation chamber for collection of strong solution, pump means for discharging the strong solution from the sump and onto the heat-out side of the heat transfer wall exposed to the evaporation chamber, and a strong absorbent solution line from the sump and through the low temperature heat exchanger and discharging into the absorber of the chiller system, whereby the chilling effect applied to the heat-in coil of the chiller system is maximized.

38. The vapor recompression absorber and chiller system as set forth in claim 37, wherein the absorbent material is a Lithium-Bromide (LiBr) salt.

39. The vapor recompression absorber and chiller system as set forth in claim 37, wherein the upper absorption chamber, the lower vapor evaporation chamber and the sump open from the evaporation chamber are all incorporated within a common tank.

40. The vapor recompression absorber and chiller system as set forth in claim 39, wherein said two chambers are separated by a multiplicity of panels forming said heat transfer wall.

41. The vapor recompression absorber and chiller system as set forth in claim 39, wherein said two chambers are separated by a concentric assembly of ring-shaped panels forming said heat transfer wall interconnected by top and bottom headers with spaces between said adjacent pairs of panels and alternately open into the upper and lower chambers.

42. The vapor recompression absorber and chiller system ass set forth in claim 41, wherein the collection means for recirculating weakened solution is connected to said bottom headers by a manifold for said recirculation of solution to the system concentrator.

43. The vapor recompression absorber and chiller system as set forth in claim 37, wherein the heat transfer wall is a panel of polymer material.

45. The vapor recompression absorber and chiller system as set forth in claim 37, wherein the heat transfer wall is a polymer membrane of a thickness ranging from 0.20 to 0.40 mm.

46. The vapor recompression absorber and chiller system as set forth in claim 37, wherein the means for discharging solution onto the heat-in and heat-out sides of the heat transfer wall are weir means, the solutions being applied to the sides of the wall as falling films.

47. The vapor recompression absorber and chiller system as set forth in claim 37, wherein the vapor compressor means is a low pressure blower open from the evaporation chamber and into the absorption chamber.

48. The vapor recompression absorber and chiller system as set forth in claim 47, wherein the vapor compressor means blower operates at a pressure on the order of 3 to 6 inches water gage.

44. The vapor recompression absorber and chiller system as set forth in clam 37, wherein the heat transfer wall is a thin membrane of polymer material.