Gas pressure reduction generator

• US 8,857,170 B2
• Filed: 12/30/2010
• Issued: 10/14/2014
• Est. Priority Date: 12/30/2010
• Status: Active Grant

• Current Assignee: Bitzer US Incorporated (Bitzer Se)
• Original Assignee: ElectraTherm Inc (Bitzer Se)
• Inventors: Langson, Richard K., Oxner, Andrew
• Primary Examiner(s): Landrum, Ned
• Assistant Examiner(s): KRAFT, LOGAN M
• Application Number:
  US12/982,167
• Publication Number:
  US 20120169049A1
• Time in Patent Office: 1,384 Days
• Field of Search: 603/98, 604/07, 604/09, 604/13, 604/56
• US Class Current: 60/456
• CPC Class Codes: F01C 1/16 with helical teeth, e.g. chevron-shaped, screw type for non-parallel axes of movement F01C3/00
• CPC Class Codes: F01C 13/00 Adaptations of machines or engines for special use; Combinations of engines with devices driven thereby
• CPC Class Codes: F01C 20/26 using bypass channels
• CPC Class Codes: F01C 21/04 Lubrication of machines or engines in general F01M
• CPC Class Codes: F01D 15/10 Adaptations for driving, or combinations with, electric generators
• CPC Class Codes: F01K 7/00 Steam engine plants characterised by the use of specific types of engine F01K3/02 takes precedence; Plants or engines characterised by their use of special steam systems, cycles or processes reciprocating-piston engines using uniflow principle F01B17/04; Control means specially adapted for such systems, cycles or processes; Use of withdrawn or exhaust steam for feed-water heating
• CPC Class Codes: F05B 2210/30 Flow characteristics
• CPC Class Codes: F05B 2260/40 Transmission of power
• CPC Class Codes: F05B 2260/98 Lubrication
• CPC Class Codes: H02K 7/1823 structurally associated with turbines or similar engines

Abstract

A Gas Pressure Reduction Generator (GPRG) System and a method for implementing a GPRG System is provided, where the GPRG System includes a gas inlet configured to receive a pressurized gas flow from a gas supply, at least one expander in flow communication with the gas inlet to receive the pressurized gas flow, wherein the expander is operable to convert the pressurized gas flow into mechanical energy and a depressurized gas flow and a generator associated with the expander, wherein the generator is configured to convert the mechanical energy into electrical energy.

Claims

1. A gas pressure reduction generator system comprising in combination:

A. a pressurized gas flow inlet;

B. one or more expander/generator apparatuses, each such expander/generator apparatus separately comprising;

(i) a pressurized gas expander including a pressurized gas expander inlet in pressurized gas flow communication with the pressurized gas flow inlet, and a reduced pressure gas expander outlet;

(ii) an electric power generator in mechanical power receiving communication with the pressurized gas expander, said electric power generator configured to generate and deliver constant frequency alternating current electric power to an electrical load; and

(iii) a lubrication system comprising an oil separator/reservoir in input oil flow communication with the reduced pressure gas expander outlet and in output oil flow communication with the pressurized gas expander via an oil heater and an oil pump.

2. The gas pressure reduction generator system of claim 1 wherein at least one expander/generator apparatus is configured to generate and deliver constant frequency alternating current electric power to an electrical load by further comprising a rotational speed monitoring device and a rotational speed governor.

3. The gas pressure reduction generator system of claim 1 wherein at least one expander/generator apparatus comprises a screw expander in power delivery communication with the electric power generator.

4. The gas pressure reduction generator system of claim 1 wherein the oil heater is disposed between the oil separator/reservoir and the oil pump.

5. The gas pressure reduction generator system of claim 1 wherein the oil pump is disposed between the oil separator/reservoir and the oil heater.

6. A gas pressure reduction generator system comprising:

A. a pressurized system gas flow inlet configured to receive pressurized gas from a gas supply;

B. a pressurized gas rotational speed governor in pressurized gas flow communication with the pressurized system flow gas inlet;

C. one or more pressurized gas expander(s), each pressurized gas expander separately comprising;

(i) a pressurized gas expander inlet in pressurized gas flow communication with the pressurized gas rotational speed governor,

(ii) a rotating pressurized gas expander shaft,

(iii) a pressurized gas expander shaft rotation monitor in communication with the pressurized gas rotational speed governor, wherein the rotational speed of the rotating pressurized gas expander shaft is controlled by the pressurized gas rotational speed governor in communication with the pressurized gas rotational speed monitor, and

(iv) a reduced pressure gas expander outlet;

D. a reduced pressure system gas flow outlet in reduced pressure gas flow receiving communication with at least one reduced pressure gas expander outlet of the one or more pressurized gas expanders; and

E. one or more alternating current electric power generator(s) in power receiving communication with at least one pressurized gas expander via the rotating expander shaft of said pressurized gas expander and in alternating current electric power delivery communication with at least one electric power load, wherein the frequency of at least one of the one or more alternating current electric power generator(s) is determined by the speed of the rotating expander shaft.

7. The system of claim 6 wherein the pressurized gas received from the gas supply comprises natural gas.

8. The system of claim 7 wherein the pressurized gas expander shaft rotation monitor of at least one of the one or more pressurized gas expanders is in communication with the pressurized gas rotational speed governor.

9. The gas pressure reduction generator system of claim 7 wherein the pressurized gas rotational speed governor is in data communication with the pressurized gas expander shaft rotation monitor of at least one of the one or more pressurized gas expanders.

10. The system of claim 7 wherein at least one of the one or more pressurized gas expander(s) further comprises a lubricant oil inlet in lubricant providing communication with a working chamber and one or more bearings of the pressurized gas expander.

11. The system of claim 10 further comprising an oil separator system in (a) gas and oil flow receiving communication with at least one reduced pressure gas expander outlet of the one or more pressurized gas expander(s), and (b) oil supplying communication with at least one lubricant oil inlet of the one or more pressurized gas expander(s).

12. The system of claim 11 wherein the oil separator system further comprises an oil heater and an oil pump.

13. The system of claim 11 wherein the oil separator system includes a reduced pressure gas and oil reservoir in reduced pressure gas and oil receiving communication with at least one reduced pressure gas expander outlet of the one or more pressurized gas expander(s).

14. The system of claim 7 wherein at least one of the one or more pressurized gas expander(s) comprises a screw expander.

15. The system of claim 14 wherein the at least one screw expander comprises an N-profile rotor.

16. The system of claim 6 wherein the pressurized gas expander shaft rotation monitor of at least one of the one or more pressurized gas expanders is in communication with the pressurized gas rotational speed governor.

17. The gas pressure reduction generator system of claim 6 wherein the pressurized gas rotational speed governor is in data communication with the pressurized gas expander shaft rotation monitor of at least one of the one or more pressurized gas expanders.

18. The system of claim 6 wherein at least one of the one or more pressurized gas expander(s) further comprises a lubricant oil inlet in lubricant providing communication with a working chamber and one or more bearings of the pressurized gas expander.

19. The system of claim 18 further comprising an oil separator system in (a) gas and oil flow receiving communication with at least one reduced pressure gas expander outlet of the one or more pressurized gas expander(s), and (b) oil supplying communication with at least one lubricant oil inlet of the one or more pressurized gas expander(s).

20. The system of claim 19 wherein the oil separator system further comprises an oil heater and an oil pump.

21. The system of claim 19 wherein the oil separator system includes a reduced pressure gas and oil reservoir in reduced pressure gas and oil receiving communication with at least one reduced pressure gas expander outlet of the one or more pressurized gas expander(s).

22. The system of claim 6 wherein at least one of the one or more pressurized gas expander(s) comprises a screw expander.

23. The system of claim 22 wherein the at least one screw expander comprises an N-profile rotor.

24. A method of reducing gas pressure and generating electrical power comprising:

A. receiving a pressurized gas flow;

B. receiving a flow of lubricating oil;

C. introducing the pressurized gas flow into a pressurized gas expander;

D. introducing the flow of lubricating oil into the pressurized gas expander, thereby combining it with the pressurized gas flow;

E. expanding the pressurized gas flow in the pressurized gas expander and generating mechanical power and a reduced pressure gas flow;

F. communicating the mechanical power to an electric generator;

G. separating lubricating oil from the reduced pressure gas flow, heating the lubricating oil, and creating the flow of lubricating oil; and

H. delivering the reduced pressure gas flow to a reduced pressure gas outlet.

25. The method of claim 24 wherein the pressurized gas flow comprises a pressurized flow of natural gas.

26. The method of claim 25, wherein the steps (E) and (F) of expanding, generating, and communicating further comprise (i) causing an expander shaft to rotate, and (ii) transferring rotational energy from said rotating expander shaft to a rotating shaft in the electric generator.

27. The method of claim 25 wherein the separating portion of step (G) further comprises delivering the reduced pressure gas and oil flow to a reduced pressure gas and oil reservoir.

28. The method of claim 24, wherein the steps (E) and (F) of expanding, generating, and communicating further comprise (i) causing an expander shaft to rotate, and (ii) transferring rotational energy from said rotating expander shaft to a rotating shaft in the electric generator.

29. The method of claim 24 wherein the separating portion of step (G) further comprises delivering the reduced pressure gas and oil flow to a reduced pressure gas and oil reservoir.

30. A method of reducing gas pressure and generating electrical power comprising:

A. receiving a pressurized gas flow;

B. receiving a flow of lubricating oil;

C. introducing the pressurized gas flow into a pressurized gas expander;

D. introducing the flow of lubricating oil into the pressurized gas expander, thereby combining it with the pressurized gas flow;

E. expanding the pressurized gas flow in the pressurized gas expander and generating mechanical power and a reduced pressure gas flow;

F. monitoring the rotational speed of the expander shaft and controlling said rotational speed via a pressurized gas rotational speed governor;

G. communicating the mechanical power to an electric generator;

H. separating lubricating oil from the reduced pressure gas flow and creating the flow of lubricating oil; and

I. delivering the reduced pressure gas flow to a reduced pressure gas outlet.

31. The method of claim 30 wherein the pressurized gas flow comprises a pressurized flow of natural gas.

32. The method of claim 31 wherein the step H of separating lubricating oil from the reduced pressure gas flow further comprises heating the lubricating oil.

33. The method of claim 31, wherein the steps (E) and (G) of expanding, generating, and communicating further comprise (i) causing an expander shaft to rotate, and (ii) transferring rotational energy from said rotating expander shaft to a rotating shaft in the electric generator.

34. The method of claim 31 wherein the separating portion of step (H) further comprises delivering the reduced pressure gas and oil flow to a reduced pressure gas and oil reservoir.

35. The method of claim 30 wherein the step H of separating lubricating oil from the reduced pressure gas flow further comprises heating the lubricating oil.

36. The method of claim 30, wherein the steps (E) and (G) of expanding, generating, and communicating further comprise (i) causing an expander shaft to rotate, and (ii) transferring rotational energy from said rotating expander shaft to a rotating shaft in the electric generator.

37. The method of claim 30 wherein the separating portion of step (H) further comprises delivering the reduced pressure gas and oil flow to a reduced pressure gas and oil reservoir.