Integrated energy recovery system

• US 20040074850A1
• Filed: 04/23/2003
• Published: 04/22/2004
• Est. Priority Date: 04/24/2002
• Status: Abandoned Application

• Current Assignee: Praxair Technology Incorporated (Linde Plc)
• Original Assignee: Praxair Technology Incorporated (Linde Plc)
• Inventors: Kelly, Richard Martin
• Application Number:
  US10/422,074
• Publication Number:
  US 20040074850A1
• Time in Patent Office: Days
• US Class Current: 210/806
• CPC Class Codes: B01D 1/2884 Multiple effect compression B01D1/2815 takes precedence
• CPC Class Codes: C02F 1/001 Processes for the treatment of water whereby the filtration technique is of importance C02F1/44 takes precedence; construction of filters in general B01D24/00 - B01D41/00
• CPC Class Codes: C02F 1/02 by heating methods of steam generation F22B; preheating boiler feed-water or accumulating preheated boiler feed-water F22D
• CPC Class Codes: C02F 1/20 by degassing, i.e. liberation of dissolved gases degasification of liquids in general B01D19/00; arrangement of degassing apparatus in boiler feed supply F22D
• CPC Class Codes: C02F 1/32 with ultraviolet light
• CPC Class Codes: C02F 1/42 by ion-exchange ion-exchange in general B01J
• CPC Class Codes: C02F 1/441 by reverse osmosis
• CPC Class Codes: C02F 2103/04 for obtaining ultra-pure water
• CPC Class Codes: C02F 9/00 Multistage treatment of water, waste water or sewage
• CPC Class Codes: F25J 2230/04 Compressor cooling arrangement, e.g. inter- or after-stage cooling or condensate removal
• CPC Class Codes: F25J 2270/90 External refrigeration, e.g. conventional closed-loop mechanical refrigeration unit using Freon or NH3, unspecified external refrigeration
• CPC Class Codes: F25J 3/04018 of main feed air
• CPC Class Codes: F25J 3/0403 of nitrogen
• CPC Class Codes: F25J 3/04612 Heat exchange integration with process streams, e.g. from the air gas consuming unit
• CPC Class Codes: F25J 3/04618 for cooling an air stream fed to the air fractionation unit
• CPC Class Codes: Y02P 70/10 Greenhouse gas [GHG] capture, material saving, heat recovery or other energy efficient measures, e.g. motor control, characterised by manufacturing processes, e.g. for rolling metal or metal working

Abstract

The present invention relates to the recovery of heat energy, e.g., the heat of compression, from the production of pressurized gases, in particular nitrogen (N₂), but also other gases such as compressed dry air. This invention is directed to a system and method for increasing the efficiency in use of energy by recovering energy normally wasted in one device and using the energy in another device needing the energy. In particular, this invention is directed to recovering the heat of compression from a gas generation plant to warm cooling water that is also used as feed water to an ultra pure water generation plant.

Claims

1. A system for producing compressed gas and purified water comprising:

(a) means for compressing a gas, thereby forming a heat source;

(b) means for transferring heat from the heat source to a water stream, thereby forming a heated water stream; and

(c) means for purifying the heated water stream.

2. The system of claim 1 wherein the means for transferring heat from the heat source to the water stream is an indirect heat exchanger.

3. The system of claim 1 wherein the means for purifying the heated water stream is a reverse osmosis water purification device.

4. The system of claim 3 further comprising means for further purifying the heated water stream.

5. The system of claim 4 wherein the means for further purifying the heated water stream comprises one or more devices selected from the group consisting of deionization units, degasification units, ultraviolet sterilization units, and filters.

6. The system of claim 1 wherein the means for purifying the heated water stream is an ultra pure water generation system.

7. The system of claim 1 wherein the means for compressing the gas is a multistage compression apparatus.

8. The system of claim 6 wherein the means for transferring heat from the heat source to a water stream comprises means for providing heat exchange from a compressed gas stream to a water stream at each stage of the multistage compression apparatus.

9. The system of claim 1 further comprising a gas source, the gas source being in fluid communication with the means for compressing the gas.

10. The system of claim 9 wherein the gas source is a nitrogen gas source.

11. The system of claim 1 further comprising means for diverting a portion of the heated water stream from the means for purifying the heated water stream.

12. The system of claim 1 further comprising means for combining the heated water stream with a feed water stream and means for directing the combined streams to the means for purifying the heated water stream.

13. A system for producing compressed gas and purified water comprising:

(a) a gas compressor for producing a compressed gas stream;

(b) at least one heat exchanger having a compressed gas inlet, a compressed gas outlet, a water inlet and a water outlet and wherein heat is transferred from the compressed gas stream to a water stream to produce a heated water stream; and

(c) a water purification apparatus for purifying the heated water stream, the water purification apparatus being in fluid communication with the heat exchanger.

14. The system of claim 13 further comprising means for combining the heated water stream with a feed water stream and means for directing the combined streams to the water purification apparatus for purification of the combined streams.

15. The system of claim 13 wherein the water purification apparatus is a reverse osmosis water purification device.

16. The system of claim 15 further comprising means for further purification of the heated water stream.

17. The system of claim 16 wherein the means for further purification of the heated water stream comprises one or more devices selected from the group consisting of deionization units, degasification units, ultraviolet sterilization units, and filters.

18. The system of claim 13 further comprising a gas source, the gas source being in fluid communication with the gas compressor.

19. The system of claim 18 wherein the gas source is a nitrogen gas source.

20. The system of claim 13 wherein the gas compressor is a multistage gas compressor.

21. A method for producing compressed gas and purified water comprising:

(a) compressing a gas to produce a compressed gas stream;

(b) directing the compressed gas stream through a heat exchanger wherein heat is transferred from the compressed gas to a water stream, thus producing a heated water stream; and

(c) directing the heated water stream to a water purification apparatus wherein the heated water stream is at least partially purified to form a purified water stream.

22. The method of claim 21 wherein the water purification apparatus is a reverse osmosis water purification device.

23. The method of claim 22 further comprising the step of further purifying the purified water stream using one or more devices selected from the group consisting of deionization units, degasification units, ultraviolet sterilization units, and filters.

24. The method of claim 21 wherein the heated water stream is purified to thereby form ultra purified water.

25. The method of claim 21 wherein the heat exchanger is an indirect heat exchanger.

26. The method of claim 21 further comprising the step of employing the compressed gas stream and purified water stream in semiconductor device fabrication.

27. The method of claim 21 further comprising the step of combining the heated water stream with a water feed stream and directing the combined streams into the water purification apparatus.

28. The method of claim 21 further comprising the step of further heating the heated water stream prior to directing the heated water stream to the water purification apparatus.