Thermal to mechanical energy conversion method using a rankine cycle equipped with a heat pump

Patent metadata

Field	Value
Publication number	US-10132199-B2
Application number	US-201415031416-A
Country	US
Kind code	B2
Filing date	Sep 17, 2014
Priority date	Oct 30, 2013
Publication date	Nov 20, 2018
Grant date	Nov 20, 2018

Abstract

The invention relates to a thermal to energy conversion method and system using a Rankine cycle equipped with a heat pump, wherein heat pump (2) is integrated in the Rankine cycle.

First claim

The invention claimed is:

1. A thermal to mechanical energy conversion method comprising:
circulating a working fluid in a circuit which operates as a Rankine closed loop and includes a heat pump which heats the working fluid that is vaporized, heated and inputted into a turbine in the Rankine closed loop cycle to produce the mechanical energy;
separating the vaporized working fluid flowing in the Rankine closed loop into a first portion and a second portion;
prior to inputting the first portion into the turbine, compressing the second portion with a compressor within the heat pump to heat the second portion, and flowing the first portion and the heated second portion through a heat exchanger to heat the first portion; and
inputting the heated first portion into the turbine to produce the mechanical energy.

2. A method as claimed in claim 1 , comprising:
taking seawater from heat sources which are respectively seawater taken at different depths with a first heat source at a shallower depth being used for vaporizing the working fluid and a second heat source at a greater depth being used for condensing the working fluid.

3. A method as claimed in claim 1 , wherein the working fluid comprises ammonia.

4. A method as claimed in claim 1 , wherein:
the first portion is mixed with at least part of the second portion after being inputted into the turbine.

5. A method as claimed in claim 4 , wherein the working fluid comprises ammonia.

6. A method as claimed in claim 4 , comprising:
vaporizing the working fluid by thermal exchange with a first heat source;
flowing the first portion through the turbine to produce the mechanical energy;
partially re-forming the working fluid by mixing at least part of the first and second portions after the first portion has flowed through the turbine;
condensing at least part of the re-formed working fluid by heat exchange with a second heat source; and
compressing the working fluid after condensing at least part of the re-formed working fluid.

7. A method as claimed in claim 6 , comprising:
taking seawater from heat sources which are respectively seawater taken at different depths with a first heat source at a shallower depth being used for vaporizing the working fluid and a second heat source at a greater depth being used for condensing the working fluid.

8. A method as claimed in claim 6 , comprising:
upstream from re-forming part of the working fluid, separating the second portion into a liquid phase and a gas phase;
mixing the gas phase of the second portion with the first portion to partially re-form the working fluid; and
mixing the liquid phase of the second portion with a condensed portion of the working fluid to convert the working fluid into liquid.

9. A method as claimed in claim 8 , comprising:
taking seawater from heat sources which are respectively seawater taken at different depths with a first heat source at a shallower depth being used for vaporizing the working fluid and a second heat source at a greater depth being used for condensing the working fluid.

10. A method as claimed in claim 6 , comprising:
separating the working fluid into a liquid phase and a gas phase with the gas phase of the working fluid being condensed by the condensing (SF) of the working fluid; and
mixing the liquid phase of the working fluid with the condensed working fluid to convert all of the working fluid into liquid.

11. A method as claimed in claim 10 , comprising:
taking seawater from heat sources which are respectively seawater taken at different depths with a first heat source at a shallower depth being used for vaporizing the working fluid and a second heat source at a greater depth being used for condensing the working fluid.

12. A method as claimed in claim 1 , comprising:
vaporizing the working fluid by thermal exchange with a first heat source;
flowing the first portion through the turbine to produce the mechanical energy;
partially re-forming the working fluid by mixing at least part of the first and second portions after the first portion has flowed through the turbine;
condensing at least part of the re-formed working fluid by heat exchange with a second heat source; and
compressing the working fluid after condensing at least part of the re-formed working fluid.

13. A method as claimed in claim 12 , comprising:
taking seawater from heat sources which are respectively seawater taken at different depths with a first heat source at a shallower depth being used for vaporizing the working fluid and a second heat source at a greater depth being used for condensing the working fluid.

14. A method as claimed in claim 12 , wherein the working fluid comprises ammonia.

15. A method as claimed in claim 12 , comprising:
upstream from re-forming part of the working fluid, separating the second portion into a liquid phase and a gas phase;
mixing the gas phase of the second portion with the first portion to partially re-form the working fluid; and
mixing the liquid phase of the second portion with a condensed portion of the working fluid to convert the working fluid into liquid.

16. A method as claimed in claim 15 , comprising:
taking seawater from heat sources which are respectively seawater taken at different depths with a first heat source at a shallower depth being used for vaporizing the working fluid and a second heat source at a greater depth being used for condensing the working fluid.

17. A method as claimed in claim 15 , wherein the working fluid comprises ammonia.

18. A method as claimed in claim 12 , comprising:
separating the working fluid into a liquid phase and a gas phase with the gas phase of the working fluid being condensed by the condensing (SF) of the working fluid; and
mixing the liquid phase of the working fluid with the condensed working fluid to convert all of the working fluid into liquid.

19. A method as claimed in claim 18 , comprising:
taking seawater from heat sources which are respectively seawater taken at different depths with a first heat source at a shallower depth being used for vaporizing the working fluid and a second heat source at a greater depth being used for condensing the working fluid.

20. A method as claimed in claim 18 , wherein the working fluid comprises ammonia.

21. A thermal to mechanical energy conversion system comprising:
a Rankine cycle closed loop which circulates a working fluid and includes a heat pump which heats the working fluid which is inputted into a turbine to produce mechanical energy;
a separator for separating vaporized working fluid flowing in the Rankine closed loop cycle into first and second portions;
a compressor which compresses the second portion to heat the second portion; and
a heat exchanger through which the first portion and the heated second portion flows to heat the first portion prior to inputting the first portion into the turbine to produce the mechanical energy.

22. A system as claimed in claim 21 , wherein the closed circuit comprises:
a first heat exchanger for vaporizing the working fluid with a first heat source which is sea water from a shallower depth;
a first mixer for mixing at least part of the first and second portions to re-form the working fluid after the working fluid passes through the turbine;
a valve or two-phase pump for expanding the second portion before mixing with the first mixer; and
a second heat exchanger for condensing at least part of the working fluid by heat exchange from a second h

Assignees

• Ifp Energies Now

Inventors

• Mabile Claude

Classifications

• F01K11/02

  the engines being turbines · CPC title

• Y02E10/34

  Cross-Sectional Technologies · mapped topic

• F01K25/106

  Ammonia (F01K25/065 takes precedence) · CPC title

• F01K23/02

  the engine cycles being thermally coupled · CPC title

• F01K17/005 Primary

  by means of a heat pump (heat pumps systems per se F25B) · CPC title