Apparatus and method for removing condensable material from a gas

• US 5,794,453 A
• Filed: 07/22/1996
• Issued: 08/18/1998
• Est. Priority Date: 07/22/1996
• Status: Expired due to Term

• Current Assignee: Flair Corporation
• Original Assignee: Flair Corporation
• Inventors: Barnwell, James W.
• Primary Examiner(s): Wayner, William E.
• Application Number:
  US08/681,328
• Time in Patent Office: 757 Days
• Field of Search: 62/90, 62/93, 62/129, 62/173, 62/79, 62/80, 95/39
• US Class Current: 62/79
• CPC Class Codes: B01D 5/0039 Recuperation of heat, e.g. use of heat pump(s), compression
• CPC Class Codes: B01D 53/002 by condensation
• CPC Class Codes: B01D 53/265 by refrigeration (condensation)

Abstract

An improved method and apparatus is disclosed for removing condensable material from a gas. The gas is caused to flow in series through a chiller for cooling the gas and condensing the condensable material from the gas, then through a separator to separate the condensate from the gas, and then passing the gas through a reheater to reheat the gas. A predetermined charge of refrigerant is passed in a closed cycle through the chiller to cool the gas by absorbing the heat from the gas and evaporating, then the gaseous refrigerant is compressed by a compression unit having an electric drive means in which an amount of energy is added to the gaseous refrigerant. The hot, pressurized, gaseous refrigerant is then passed through an auxiliary condenser sized to remove the energy that was added to the refrigerant by the compression unit at no load conditions, then the refrigerant is passed through the reheater to further condense the refrigerant and to transfer heat to the exiting gas. The refrigerant then exits the reheater and returns to the chiller, completing the closed cycle. The predetermined charge of refrigerant is sized to cause the refrigerant exiting the reheater to be in a substantially gaseous state when there is no flow of gas through the reheater and to cause the pressure of the refrigerant exiting the reheater to generally decrease as the flow of gas through the reheater increases.

Claims

1. An apparatus for removing condensable material from a gas comprising:

a flow through gas system which includes in series a chiller for cooling said gas and condensing said condensable material from said gas, a separator for separating said condensed material from said gas and draining away said condensate, and a reheater for reheating said gas;

a closed refrigerant system which passes a predetermined charge of refrigerant in series through said chiller to cool said gas by absorbing heat from said gas and evaporating, through a compression unit in which said refrigerant is compressed and an amount of energy is added thereto, then through an auxiliary condenser sized to remove from said refrigerant the energy added thereto by said compression unit at no load conditions, and then through said reheater and back to said chiller; and

wherein said predetermined charge of refrigerant is sized to cause said refrigerant exiting said reheater to be substantially in a gaseous state when there is no flow of gas and to cause the pressure of said refrigerant exiting said reheater to generally decrease as said flow of gas through said reheater increases.

2. The apparatus of claim 1, further comprising a refrigerant expansion device through which the refrigerant passes after leaving the reheater and before entering the chiller.

3. The apparatus of claim 2, wherein the predetermined charge of refrigerant is further sized to cause said refrigerant entering said refrigerant expansion device to be in the liquid state when there is gas flow and in the gaseous state when there is no gas flow.

4. The apparatus of claim 2, further comprising a refrigerant filter/dryer to remove water and particulate matter from said refrigerant through which said refrigerant passes after leaving said reheater and before entering said expansion device.

5. The apparatus of claim 1, further comprising a refrigerant filter/dryer to remove water and particulate matter from said refrigerant through which the refrigerant passes after leaving the reheater and before entering the chiller.

6. The apparatus of claim 1, wherein said compression unit includes a compressor and an electric drive motor, said motor having windings over which said refrigerant passes to cool said motor before said refrigerant is compressed.

7. The apparatus of claim 6, wherein said compressor is a piston compressor.

8. The apparatus of claim 6, wherein said compression unit is hermetically sealed.

9. The apparatus of claim 1, further comprising a temperature sensitive color change label downstream of the reheater and upstream of the chiller for sensing the temperature of the refrigerant passing thereby.

10. The apparatus of claim 1, wherein the gas is compressed.

11. The apparatus of claim 1, wherein the gas is air.

12. The apparatus of claim 1, wherein the condensable material is water.

13. The apparatus of claim 1, wherein the auxiliary condenser is part of the external structure of the apparatus.

14. The apparatus of claim 1, wherein the auxiliary condenser exchanges heat to air by forced movement of the air thereover.

15. The apparatus of claim 1, wherein the refrigerant is a halogenated hydrocarbon.

16. The apparatus of claim 15, wherein the refrigerant is a halogenated hydrocarbon selected from the group consisting of R-12, R-22, and R-134a.

17. A method of removing condensable material from a gas comprising the steps of:

causing said gas to flow in series through a chiller for cooling said gas and condensing said condensable material from said gas, then through a separator for separating said condensed material from said gas and draining away said condensate, and then through a reheater for reheating said gas;

passing a predetermined charge of refrigerant in series through said chiller to cool said gas by absorbing heat from said gas and evaporating, through a compression unit in which said refrigerant is compressed and an amount of energy is added to the refrigerant, then through an auxiliary condenser sized to remove from said refrigerant the energy added thereto by said compression unit under no load conditions, and then through said reheater and back to said chiller; and

sizing said predetermined charge of refrigerant to cause said refrigerant exiting said reheater to be in a substantially gaseous state when there is no flow of gas and to cause the pressure of said refrigerant exiting said reheater to generally decrease as said flow of gas through said reheater increases.

18. The method of claim 17, further comprising the step of passing the refrigerant through a refrigerant expansion device after passing through said reheater and before passing through said chiller.

19. The method of claim 18, wherein the step of sizing said predetermined charge of refrigerant further comprises causing said refrigerant to be in a substantially liquid state when entering the refrigerant expansion device during periods of gas flow, and in a substantially gaseous state during periods of no gas flow.

20. The method of claim 18, further comprising passing said refrigerant through a filter/dryer to remove water and particulate matter from said refrigerant after passing through said reheater, and before passing through said expansion device.

21. The method of claim 17, further comprising passing said refrigerant through a filter/dryer to remove water and particulate matter from said refrigerant after passing through said reheater and before passing through said chiller.

22. The method of claim 17, further comprising the step of passing the refrigerant past a temperature sensitive color change label after passing through said reheater and before passing through said chiller to determine the approximate temperature of the refrigerant.

23. An apparatus for removing condensable material from a compressed gas comprising:

a flow through compressed gas system which includes in series a chiller for cooling said compressed gas and condensing said condensable material from said compressed gas, a separator for separating said condensed material from said compressed gas and draining away said condensate, and a reheater for reheating said compressed gas;

a closed refrigerant system which passes a predetermined charge of refrigerant in series through said chiller to cool said compressed gas by absorbing heat from said compressed gas and evaporating, through a compression unit having a compressor and a refrigerant-cooled, electric drive means in which said refrigerant is compressed and an amount of energy is added thereto, then through an auxiliary condenser sized to remove from said refrigerant the energy added thereto by said compression unit under no load conditions, through said reheater, through a refrigerant filter/dryer to remove water and particulate matter from said refrigerant, through a refrigerant expansion device, past a temperature sensitive color change label to determine the approximate temperature of said refrigerant, and then back to said chiller; and

wherein said predetermined charge of refrigerant is sized to cause said refrigerant exiting said reheater to be substantially in a gaseous state during periods of no compressed gas flow, to cause the pressure of said refrigerant exiting said reheater to generally decrease as said flow of compressed gas through said reheater increases, and to ensure that there is a liquid refrigerant seal at the refrigerant expansion device during periods of compressed gas flow, with the auxiliary condenser being part of the external structure of the apparatus.