Power plant with CO2 capture and method to operate such power plant

Patent metadata

Field	Value
Publication number	US-9611762-B2
Application number	US-201013514663-A
Country	US
Kind code	B2
Filing date	Nov 29, 2010
Priority date	Dec 8, 2009
Publication date	Apr 4, 2017
Grant date	Apr 4, 2017

Abstract

A fossil fuel fired power plant for the generation of electrical energy comprises a water steam cycle and a plant ( 10 ) for the capture of CO2 from exhaust gases emitted by the power plant and a steam jet ejector ( 24 ) configured and arranged to receive an input steam flow from a low- or intermediate pressure extraction point in the power plant and to increase its pressure. It is further arranged to receive motive steam ( 25 ) from a further extraction point in the power plant. A steam line ( 27, 22 ) directs the steam of increased pressure from the steam jet ejector ( 24 ) to the CO2 capture plant ( 10 ). The power plant according to this invention allows the use of low-pressure steam for the operation of the CO2 capture plant, where the extraction of such steam affects the overall efficiency of the power plant to a lesser degree than in power plant of the state of the art.

First claim

The invention claimed is:

1. A fossil fuel fired power plant for the generation of electrical energy having a water steam cycle and a plant for the capture of CO2 from exhaust gases emitted by the power plant; the power plant comprising;
a steam jet ejector configured and arranged between the water steam cycle and the CO2 capture plant to receive an input steam flow extracted from the water steam cycle of the power plant via a steam line for an input steam flow, and to receive a motive steam flow extracted from the water steam cycle via a steam line for motive steam flow, wherein the steam jet ejector is configured to increase the pressure of the input steam flow to a pressure equal to or higher than a pressure required for the CO2 capture plant operation; and
a line for an output steam flow leading from the steam jet ejector to the CO2 capture plant.

2. The fossil fuel fired power plant according to claim 1 , wherein
the steam line for the input steam flow leads from an extraction point at an intermediate-pressure steam turbine of the power plant or from a point in the water steam cycle downstream from the extraction point at the intermediate-pressure steam turbine.

3. The fossil fuel fired power plant according to claim 1 , wherein
the power plant further comprises a steam line for input steam flow leading from a cross-over line between an intermediate-pressure steam turbine and a low-pressure steam turbine to the steam jet ejector.

4. The fossil fuel fired power plant according to claim 1 , wherein
the power plant further comprises a steam line for input steam flow leading from a low-pressure steam turbine to the steam jet ejector.

5. The fossil fuel fired power plant according to claim 1 , wherein
the power plant further comprises a steam line for input steam flow leading from an exhaust steam line between a low-pressure steam turbine and a condenser to the steam jet ejector.

6. The fossil fuel fired power plant according to claim 1 , wherein
the power plant further comprises a steam line for motive steam flow leading from a reheat line between a high-pressure steam turbine and an intermediate-pressure steam turbine to the steam jet ejector.

7. The fossil fuel fired power plant according to claim 6 , wherein
the motive steam flow is extracted at a point between the high-pressure steam turbine and a boiler or a heat recovery steam generator.

8. The fossil fuel fired power plant according to claim 6 , wherein
the motive steam flow is extracted at a point between a boiler or a heat recovery steam generator and the intermediate-pressure steam turbine.

9. The fossil fuel fired power plant according to claim 1 , wherein
the power plant comprises a steam line for motive steam flow leading from an intermediate-pressure steam turbine to the steam jet ejector.

10. The fossil fuel fired power plant according to claim 1 , wherein
the power plant further comprises a bypass steam line leading from a line for input steam flow to a line directing the steam directly to the CO2 capture plant.

11. The fossil fuel fired power plant according to claim 10 , wherein
the bypass steam line comprises a non-return valve.

12. A fossil fuel fired power plant for the generation of electrical energy having a water steam cycle and a plant for the capture of CO2 from exhaust gases emitted by the power plant; the power plant comprising;
a steam jet ejector configured and arranged to receive an input steam flow extracted from the water steam cycle of the power plant via a steam line for an input steam flow, and to receive a motive steam flow extracted from the water steam cycle via a steam line for motive steam flow, wherein the steam jet ejector is configured to increase the pressure of the input steam flow;
a line for an output steam flow leading from the steam jet ejector to the CO2 capture plant; and
a further steam jet ejector configured and arranged to receive via a line input steam from an extraction point in the water steam cycle, to receive a motive steam flow extracted from the water steam cycle, to increase the pressure of the input steam flow and to direct via a line an output steam flow to the CO2 capture plant.

13. The fossil fuel fired power plant according to claim 12 , wherein
the power plant further comprises a line for motive steam flow for one or both of the steam jet ejectors which leads from a live steam line between a boiler or a heat recovery steam generator to a high-pressure steam turbine or from the high-pressure steam turbine to one or both of the steam jet ejectors.

14. A method of operating a power plant, the method comprising:
when operating the power plant within a full or part-load range, extracting steam from a water steam cycle of the power plant at an intermediate-pressure turbine or at a point downstream of the intermediate-pressure turbine and directing the extracted steam from the water steam cycle of the power plant to a first steam jet ejector arranged between the water steam cycle and a CO2 capture plant, increasing pressure of the extracted steam to a pressure equal to or higher than a pressure required for the CO2 capture plant operation P R (CO2), directing the steam resulting from the steam jet ejector to the CO2 capture plant, and using it to operate the CO2 capture plant.

15. The method of operating a power plant according to claim 14 , wherein
if the pressure of the extracted steam is equal to or higher than the steam pressure P R (CO2) required to operate the CO2 capture plant, leading the extracted steam directly to the CO2 capture plant via a line that bypasses the steam jet ejector to operate the CO2 capture plant.

16. A method of operating a power plant, the method comprising:
when operating the power plant within a full or part-load range, extracting steam from a water steam cycle of the power plant at an intermediate-pressure turbine or at a point downstream of the intermediate-pressure turbine and directing it to a first steam jet ejector, increasing its pressure to a pressure equal to or higher than a pressure required for a CO2 capture plant operation P R (CO2), directing the steam resulting from the steam jet ejector to the CO2 capture plant, and using it to operate the CO2 capture plant; and
when operating the power plant within a part-load range, where the steam pressure generated by the first steam jet ejector is below the pressure required P R (CO2) for operating the CO2 capture plant, closing a line for extracted steam flow from the water steam cycle to the first steam jet ejector and directing the extracted steam flow to a second steam jet ejector, increasing the pressure of the extracted steam, and directing it to the CO2 capture plant.

Assignees

• Jönsson Staffan
• Li Hongtao
• Conte Enrico
• General Electric Technology Gmbh

Inventors

• Jönsson Staffan
• Li Hongtao
• Conte Enrico

Classifications

• F01K17/04 Primary

  for specific purposes other than heating (F01K17/06 takes precedence) · CPC title

• F01K23/064

  in combination with an industrial process, e.g. chemical, metallurgical · CPC title

• F01K23/06

  combustion heat from one cycle heating the fluid in another cycle · CPC title

• Y02E20/32

  Direct CO2 mitigation · CPC title