Gas turbine arrangement, power plant and method for the operation thereof

Patent metadata

Field	Value
Publication number	US-9806247-B2
Application number	US-201214236555-A
Country	US
Kind code	B2
Filing date	Aug 8, 2012
Priority date	Aug 25, 2011
Publication date	Oct 31, 2017
Grant date	Oct 31, 2017

Abstract

A gas turbine arrangement, a power plant having such a gas turbine arrangement and a method for operating the power plant are provided. A compressor may be mechanically coupled to a turbine which can be driven by combustion gases, such as can be generated by combustion of fuel with the compressed combustion air. An exhaust system may be used to discharge the combustion gases. One or more thermoelectric generators may be thermally coupled to the exhaust system for generating electrical energy from residual heat of the combustion gases which pass in the exhaust system. This gas turbine arrangement allows waste heat from the combustion gases to be utilized and thus the overall efficiency of the gas turbine arrangement can be increased and pollutant emissions may be lowered.

First claim

The invention claimed is:

1. A gas turbine arrangement for a power plant, comprising:
a compressor for compression of combustion air, which compressor is coupled by a shaft to a turbine which can be driven by combustion gases, the combustion gases being capable of being generated by combustion of fuel with the compressed combustion air;
an exhaust gas tract by which the combustion gases, after passing through the turbine, are discharged into the surroundings;
at least one thermoelectric generator for generating electrical energy from residual heat of the combustion gases in the exhaust gas tract, and
at least one heat transmission unit that is thermally coupled to the at least one thermoelectric generator,
wherein a heat conductivity on a surface of the heat transmission element which protrudes into the exhaust gas tract is lower than the heat conductivity on a side of the heat transmission element which faces the at least one thermoelectric generator.

2. The gas turbine arrangement as claimed in claim 1 , wherein the at least one thermoelectric generator comprises a cold side that faces a coolant line.

3. The gas turbine arrangement as claimed in claim 1 , comprising a plurality of thermoelectric generators, which are arranged one behind the other in the flow direction of the combustion gases.

4. The gas turbine arrangement as claimed in claim 3 , wherein the thermoelectric generators are decoupled thermally from one another.

5. The gas turbine arrangement as claimed in claim 3 , wherein for thermoelectric generators which are in each case adjacent, the thermoelectric generator in front in the flow direction has a lower ratio between that surface of a respective heat transmission element which faces the gas stream and the surface of the hot side of the thermoelectric generator than the thermoelectric generator at the rear in the flow direction.

6. The gas turbine arrangement as claimed in claim 2 , wherein the at least one thermoelectric generator surrounds the coolant line on the outer circumference.

7. The gas turbine arrangement as claimed in claim 6 , wherein the thermoelectric generator is arranged on the outer circumferential surface of a coolant line having a round cross section.

8. The gas turbine arrangement as claimed in claim 6 , wherein the coolant line is designed as a gap between opposite pairs of plate-shaped thermoelectric generators.

9. A power plant having a gas turbine arrangement as claimed in claim 1 .

10. The power plant as claimed in claim 9 , wherein electrical energy provided by the at least one thermoelectric generator during operation can be fed via power electronics, jointly with electrical energy provided during operation by an electric generator driven by the turbine arrangement, into a power network coupled to the power plant.

11. The power plant as claimed in claim 9 , wherein electrical energy provided by the at least one thermoelectric generator during operation can be fed into a power network internal to the power plant for the purpose of supplying consumers assigned to the power plant.

12. A method for operating a power plant having a gas turbine arrangement, in which fuel is burnt together with combustion air compressed by a compressor and a turbine coupled mechanically to the compressor, the method comprising:
driving the turbine by way of combustion gases, the combustion gases being discharged into the surroundings via an exhaust gas tract;
converting residual heat from the exhaust gases at least partially into electrical energy by way of at least one thermoelectric generator,
wherein the at least one thermoelectric generator is in thermal communication with a heat transmission unit that is in thermal communication with the exhaust gases, and
wherein a heat conductivity on a surface of the heat transmission element which protrudes into the exhaust gas tract is lower than the heat conductivity on a side of the heat transmission element which faces the at least one thermoelectric generator.

13. The method as claimed in claim 12 , wherein the electrical energy generated by the at least one thermoelectric generator is fed, together with energy generated by a generator driven by the turbine arrangement, into a power network.

14. The method as claimed in claim 12 , wherein the electrical energy generated by the at least one thermoelectric generator is used for supplying consumers internal to the power plant.

15. A gas turbine arrangement for a power plant, comprising:
a compressor coupled by a shaft to a turbine;
an exhaust gas tract configured to provide fluid communication between the turbine and the surroundings for combustion gases;
an upstream thermoelectric generator in thermal communication with relatively upstream combustion gases;
an upstream heat transmission element in thermal communication with the upstream thermoelectric generator and comprising an upstream element gas surface that faces the combustion gases and an upstream element generator surface that faces the hot side of the thermoelectric generator, wherein the upstream heat transmission element is characterized by an upstream element ratio between the upstream element gas surface and the upstream element generator surface;
a downstream thermoelectric generator in thermal communication with relatively downstream combustion gases; and
a downstream heat transmission element in thermal communication with the downstream thermoelectric generator and comprising a downstream element gas surface that faces the combustion gases and a downstream element generator surface that faces the hot side of the thermoelectric generator, wherein the downstream heat transmission element is characterized by a downstream element ratio between the downstream element gas surface and the downstream element generator surface;
wherein the upstream element ratio is lower than the downstream element ratio.

Assignees

• Hammer Thomas
• Lampenscherf Stefan
• Pham Gia Khanh
• Pickard Andreas
• Siemens Ag

Inventors

• Hammer Thomas
• Lampenscherf Stefan
• Pham Gia Khanh
• Pickard Andreas

Classifications

• F01D15/10 Primary

  Adaptations for driving, or combinations with, electric generators · CPC title

• F05D2220/76

  an electrical generator · CPC title

• F02C6/18

  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 title

• F05D2220/64

  for domestic central heating or production of electricity · CPC title

• H01L35/30 Primary

  Electricity · mapped topic