Rankine cycle power plant utilizing an organ fluid and method for using the same

• US 5,560,210 A
• Filed: 04/25/1995
• Issued: 10/01/1996
• Est. Priority Date: 12/31/1990
• Status: Expired due to Term

• Current Assignee: Ormat Technologies Incorporated (Ormat Industries Limited)
• Original Assignee: Ormat Turbines Ltd.
• Inventors: Bronicki, Lucien Y.
• Primary Examiner(s): Husar, Stephen F.
• Application Number:
  US08/428,846
• Time in Patent Office: 525 Days
• Field of Search: 60/648, 60/649, 60/651, 60/660, 60/671, 60/673
• US Class Current: 60/648
• CPC Class Codes: F01K 25/06 using mixtures of different fluids plants using mixtures of steam and gas F01K21/04
• CPC Class Codes: F01K 25/08 using special vapours

Abstract

A Rankine cycle power plant has a vaporizer member responsive to heat input for vaporizing a working fluid and producing vaporized working fluid, a turbogenerator responsive to vaporized working fluid for generating power and producing heat depleted working fluid, a condenser member responsive to said heat depleted working fluid for condensing the same and producing condensate, and suitable piping for returning said condensate to the vaporizer. The working fluid is in the form of a liquid having a plurality of fractions; at least one fraction is distilled from said liquid to produce a distillated fluid. It is this distillated fluid that is supplied to the power plant as the working fluid.

Claims

1. A method for operating a Rankine cycle power plant of the type having a vaporizer member responsive to heat input for vaporizing a working fluid and producing vaporized working fluid, a turbogenerator responsive to vaporized working fluid for generating power and producing heat depleted working fluid, a condenser member responsive to said heat depleted working fluid for condensing the same and producing condensate, and means for returning said condensate to the vaporizer, said method comprising:

a) providing a liquid having a plurality of fractions;

b) distilling at least one fraction from said liquid to produce a distillated fluid; and

c) supplying said distillated fluid to said power plant as the working fluid;

d) operating the power plant with said liquid;

e) using a member of the power plant for distilling a fraction from said liquid to produce said distillated fluid; and

f) removing the last mentioned fraction from said power plant, and thereafter operating the same with said distillated fluid.

2. A method according to claim 1 wherein the member used for distilling a fraction from said liquid is the vaporizer member.

3. A method according to claim 2 wherein said liquid is gasoline.

4. A method according to claim 1 wherein the member used for distilling a fraction from said liquid is the condenser member.

5. A method according to claim 4 wherein said liquid is gasoline.

6. A method for operating a Rankine cycle power plant of the type having a vaporizer member responsive to heat input for vaporizing a working fluid and producing vaporized working fluid, a turbogenerator responsive to vaporized working fluid for generating power and producing heat depleted working fluid, a condenser member responsive to said heat depleted working fluid for condensing the same and producing condensate, and means for returning said condensate to the vaporizer, said method comprising:

a) providing a liquid having a plurality of fractions;

b) distilling at least one fraction from said liquid to produce a distillated fluid; and

c) supplying said distillated fluid to said power plant as the working fluid;

d) operating the power plant with said liquid;

e) using a member of the power plant for distilling higher and lower boiling point fractions from said liquid to produce said distillated fluid; and

f) removing said higher and lower boiling point fractions from said power plant, and thereafter operating the same with said distillated fluid.

7. A method according to claim 6 wherein said liquid is gasoline.

8. A method according to claim 6 comprising:

a) monitoring the temperature and pressure in the members; and

b) changing the amount of said fractions in said distillated fluid in accordance with the monitored temperature and pressure in said members such that the volume flow through the power plant is kept substantially constant.

9. A method according to claim 6, wherein said turbogenerator has adjustable parameters that control the power output, said method comprising:

a) monitoring the temperature and pressure in the members; and

b) adjusting a parameter of the turbogenerator in accordance with the monitored temperature and pressure in the members such that the volume flow through the power plant is kept substantially constant.

10. A method according to claim 6 comprising adding said liquid to the vaporizer member, heating the vaporizer member to distill a fraction from the liquid in the vaporizer member, and removing the distilled fraction from the power plant.

11. A Rankine cycle power plant comprising:

a) a vaporizer member responsive to heat input for vaporizing a working fluid and producing a vaporized working fluid;

b) a turbogenerator responsive to vaporized working fluid for generating power and producing heat depleted working fluid;

c) a condenser member responsive to said heat to depleted working fluid for condensing the same and producing condensate;

d) means for returning said condensate to the vaporizer;

e) a make-up tank for storing a liquid having a plurality of fractions;

f) means for supplying liquid from the make-up tank to said power plant;

g) means associated with said vaporizer member for removing from the liquid in the vaporizer member, fractions whose boiling points are greater than a predetermined value;

h) means associated with said condenser for removing from the liquid in the condenser, fractions whose boiling points are lower than a predetermined value; and

i) storage means for storing the removed fractions in liquid form.

12. Apparatus according to claim 11 comprising:

a) means for monitoring the temperature and pressure in the members; and

b) means for selectively exchanging liquid between the storage means and the vaporizer member in response to the monitored temperature in order to maintain the power output of the turbogenerator.

13. Apparatus according to claim 12, wherein said working fluid is a hydrocarbon.

14. Apparatus according to claim 12, wherein said working fluid is gasoline.

24. Apparatus according to claim 11 comprising:

a) means for monitoring the temperature and pressure in the members; and

b) means for selectively exchanging liquid between the storage means and the vaporizer member in response to the monitored temperature and pressure.

15. A method for operating a Rankine cycle power plant of the type having a vaporizer member responsive to heat input for vaporizing a working fluid and producing vaporized working fluid, a turbogenerator responsive to vaporized working fluid for generating power and producing heat depleted working fluid, a condenser member responsive to said heat depleted working fluid for condensing the same and producing condensate, and means for returning said condensate to the vaporizer, said method comprising the steps of:

a) providing a liquid having a plurality of fractions;

b) distilling at least one fraction from said liquid to produce a distillated fluid; and

c) supplying said distillated fluid to said power plant as the working fluid;

d) transferring some of said liquid to said vaporizer member;

e) heating the vaporizer member such that only low boiling point fractions of the liquid in the vaporizer member are vaporized;

f) transferring said low boiling point fractions to a storage tank to thereby separate the low boiling point from the liquid in the vaporizer.

16. A method according to claim 15 comprising the steps of further heating the vaporizer member such that high boiling point fractions of the liquid in the vaporizer member are vaporized;

transferring the high boiling point fractions to the condenser member;

cooling the condenser member to condense some of the high boiling point fractions to form a condensate; and

transferring the condensate to a storage tank.

17. A method for operating a Rankine cycle power plant of the type having a vaporizer member responsive to heat input for vaporizing a working fluid and producing vaporized working fluid, a turbogenerator responsive to vaporized working fluid for generating power and producing heat depleted working fluid, a condenser member responsive to said heat depleted working fluid for condensing the same and producing condensate, and means for returning said condensate to the vaporizer, said method comprising the steps of:

a) providing a liquid having a plurality of fractions;

b) using said members for distilling said liquid into a plurality of distillated fluids; and

c) utilizing less than all of said distillated fluids in said power plant as the working fluid and storing the rest of said distillated fluids.

18. A method according to claim 17 including the step of using heat from a source other than said liquid for effecting the distilling of at least one fraction.

19. A method according to claim 17 wherein fluids with boiling points higher than the boiling points of the working fluid are stored separately from fluids with boiling points lower than the boiling points of the working fluid.

20. A method according to claim 17 wherein fluids with boiling points lower than the boiling points of the working fluid are derived from the vaporizer member when said liquid is distilled by said members.

21. A method according to claim 17 wherein fluids with boiling points higher than the boiling points of the working fluid are derived from the condenser member when said liquid is distilled by said members.

22. A method according to claim 17 wherein fluids with boiling points lower than the boiling points of the working fluid are derived from the vaporizer member when said liquid is distilled by said members, and wherein fluids with boiling points higher than the boiling points of the working fluid are derived from the condenser member when said liquid is distilled by said members.

23. A method according to claim 17 wherein said liquid is gasoline.

25. A method according to claim 17 comprising:

a) monitoring the temperature and pressure in the members; and

b) changing the amount of said fractions in said distillated fluid in accordance with the monitored temperature and pressure in said members such that the volume flow through the power plant is kept substantially constant.

26. A method according to claim 19, wherein said turbogenerator has adjustable parameters that control the power output, said method comprising:

a) monitoring the temperature and pressure in the members; and

b) adjusting a parameter of the turbogenerator in accordance with the monitored temperature and pressure in the members such that the volume flow through the power plant is kept substantially constant.

27. A method according to claim 17 comprising:

a) monitoring the temperature and pressure in the members; and

b) changing the amount of said fractions in said distillated fluid in accordance with the monitored temperature and pressure in said members such that the volume flow through the power plant is optimized.

28. A method according to claim 17, wherein said turbogenerator has adjustable parameters that control the power output, said method comprising:

a) monitoring the temperature and pressure in the members; and

b) adjusting a parameter of the turbogenerator in accordance with the monitored temperature and pressure in the members such that the volume flow through the power plant is optimized.

29. A method for operating a Rankine cycle power plant of the type having a vaporizer member responsive to heat input for vaporizing a working fluid and producing vaporized working fluid, a turbogenerator responsive to vaporized working fluid for generating power and producing heat depleted working fluid, a condenser member responsive to said heat depleted working fluid for condensing the same and producing condensate, and means for returning said condensate to the vaporizer, said method comprising the steps of:

a) providing a liquid having a plurality of fractions;

b) using at least one of the members for extracting at least one fraction from said liquid thereby producing a residual liquid;

c) storing the extracted fraction; and

d) using the residual liquid as the working fluid of the power plant.

30. A method according to claim 29 wherein said vaporizer member is used for extracting lower boiling point fractions.

31. A method according to claim 29 wherein said condenser member is used for extracting higher boiling point fractions.

32. A method according to claim 29 wherein said vaporizer member is used for extracting lower boiling point fractions, and said condenser member is used for extracting higher boiling point fractions from said liquid to thereby produce said residual liquid.