POWER PLANT AND METHOD FOR RETROFIT

• US 20130091845A1
• Filed: 10/16/2012
• Published: 04/18/2013
• Est. Priority Date: 10/17/2011
• Status: Active Grant

• Current Assignee: Alstom Technology Ltd. (Alstom SA)
• Original Assignee: Alstom Technology Ltd. (Alstom SA)
• Inventors: Li, Hongtao, Hoffmann, Jrgen, Droux, Francois, Ruchti, Christoph, Zagorskiy, Alexander
• Granted Patent: US 9,181,872 B2
• Time in Patent Office: Days
• US Class Current: 60/715
• CPC Class Codes: F02C 3/34 with recycling of part of the working fluid, i.e. semi-closed cycles with combustion products in the closed part of the cycle
• CPC Class Codes: F02C 6/18 using the waste heat of gas-turbine plants outside the plants themselves, e.g. gas-turbine power heat plants using waste heat as source of energy for refrigeration plants F25B27/02; using the waste heat of a gasturbine for steam generation or in a steam cycle see F01K23/10
• CPC Class Codes: F05D 2240/40 Use of a multiplicity of similar components
• CPC Class Codes: F05D 2260/61 Removal of CO2 removal of CO2 from waste gases B01D53/62
• CPC Class Codes: Y02C 20/40 of CO2
• CPC Class Codes: Y02E 20/14 Combined heat and power generation [CHP]
• CPC Class Codes: Y02E 20/16 Combined cycle power plant [CCPP], or combined cycle gas turbine [CCGT]

Abstract

A power plant includes a first gas turbine engine, a second gas turbine engine, a flue gas duct, a CO₂ capture system for treating flue gases from the second gas turbine engine and an exhaust system. It additionally includes at least one among a direct connection between the first gas turbine engine and the exhaust system, and a damper for on-line regulating the flue gases flow through it, a direct connection between the first gas turbine engine and the CO₂ capture system, and a damper for regulating the flue gases flow through it, a supply of fresh oxygen containing fluid for the second gas turbine engine.

Claims

1. Power plant comprising, connected to one another:

a first gas turbine engine,

a second gas turbine engine,

a flue gas duct, for at least partly supplying flue gases from the first gas turbine engine to the second gas turbine engine,

a CO₂ capture system for treating flue gases from the second gas turbine engine, and

an exhaust system,

the power plant further comprising at least one of;

a direct connection between the first gas turbine engine and the exhaust system, and a damper for on-line regulating the flue gases flow from the first gas turbine engine to the exhaust system,

a direct connection between the first gas turbine engine and the CO₂ capture system, and a damper for regulating the flue gases flow from the first gas turbine engine to the CO₂ capture system, or

a supply of fresh oxygen containing fluid for the second gas turbine engine between the first gas turbine engine and the second gas turbine engine.

2. The power plant according to claim 1, wherein the direct connection between the first gas turbine engine and the CO₂ capture system is branched from the flue gas duct.

3. The power plant according to claim 1, wherein the supply of fresh oxygen containing fluid is provided with a mass flow control element for on-line regulating the flow therethrough.

4. The power plant according to claim 1, wherein a heat recovery steam generator is provided between the first gas turbine engine and the second gas turbine engine.

5. The power plant according to claim 1, wherein a heat recovery steam generator connected to one or more steam turbine modules is provided downstream of the second gas turbine engine and upstream of the CO₂ capture system.

6. The power plant according to claim 1, wherein the first gas turbine engine and/or the second gas turbine engine comprise outlets and inlets and an internal recirculation line for recirculating flue gases from their outlet to their inlet.

7. The power plant according to claim 6, wherein both the first gas turbine engine and the second gas turbine engine have the internal recirculation line, and in that a connection is provided between them.

8. The power plant according to claim 1, wherein the CO₂ capture system includes a first and a second unit connected in series, wherein the first unit is connected to the second gas turbine engine and the second unit is connected to the first unit.

9. The power plant according to claim 1, further comprising an additional flue gas duct for at least partly supplying the flue gases from the second gas turbine engine to the first gas turbine engine.

10. The power plant according to claim 9, wherein the additional flue gas duct is connected to a supply of fresh oxygen containing fluid for the first gas turbine engine.

11. The power plant according to claim 1, further comprising an additional CO₂ capture system and an additional exhaust system, the additional CO₂ capture system for treating the flue gases from the first gas turbine engine.

12. The power plant according to claim 11, further comprising at least one of:

a direct connection between the second gas turbine engine and the additional exhaust system, and a damper for on-line regulating the flue gases flow from the second gas turbine engine to the additional exhaust system,

a direct connection between the second gas turbine engine and the additional CO₂ capture system, and a damper for regulating the flue gases flow from the second gas turbine engine to the additional CO₂ capture system, or

a supply of fresh oxygen containing fluid for the first gas turbine engine between the first gas turbine engine and the second gas turbine engine.

13. The power plant according to claim 1, wherein the first gas turbine engine and the second gas turbine engine extend in opposite direction and lie parallel with respect to each other.

14. Method for retrofitting a power plant comprising a gas turbine engine and an exhaust system, the method comprising:

providing at least an additional gas turbine engine, upstream or downstream of the existing gas turbine engine, such that the existing gas turbine engine defines a first gas turbine engine and the additional gas turbine engine defines a second gas turbine engine or vice versa, wherein flue gases from the first gas turbine engine are supplied to the second gas turbine engine,

providing a flue gas duct for at least partly supplying the flue gases from the first gas turbine engine to the second gas turbine engine, and

providing a CO₂ capture system for treating the flue gases from the second gas turbine engine,

the method further comprising at least one of the following steps;

providing a direct connection between the first gas turbine engine and an exhaust system, and a damper for on-line regulating the flue gases flow from the first gas turbine engine to the exhaust system,

providing a direct connection between the first gas turbine engine and the CO₂ capture system, and a damper for regulating the flue gases flow from the first gas turbine engine to the CO₂ capture system, or

providing a supply of fresh oxygen containing fluid for the second gas turbine engine between the first gas turbine engine and the second gas turbine engine.

15. The method according to claim 14, wherein the additional gas turbine engine is provided downstream of the existing gas turbine engine and the additional gas turbine engine is designed to be operated with a lower O₂ concentration than the existing gas turbine engine.