Combination power station with power/heat cogeneration

• US 6,240,718 B1
• Filed: 04/02/1998
• Issued: 06/05/2001
• Est. Priority Date: 05/17/1997
• Status: Expired due to Fees

• Current Assignee: Alstom SA
• Original Assignee: ABB Alstom Power (Switzerland) Ltd. (GE Vernova, Inc.)
• Inventors: Fetescu, Mircea
• Primary Examiner(s): FREAY, CHARLES GRANT
• Application Number:
  US09/053,783
• Time in Patent Office: 1,160 Days
• Field of Search: 60/390.7, 60/393.3, 60/391.82, 237/121
• US Class Current: 60/784
• CPC Class Codes: F01K 17/025 in combination with at least one gas turbine, e.g. a combustion gas turbine
• 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]
• CPC Class Codes: Y02P 80/15 On-site combined power, heat or cool generation or distribution, e.g. combined heat and power [CHP] supply

Abstract

A combination power station with power/heat cogeneration. The combination power station includes at least one gas turbine driven by combustion gases from a combustion chamber and at least one steam turbine working in a water/steam circuit. The water/steam circuit converts water into steam in a first apparatus by hot combustion gases emerging from the at least one gas turbine. The steam is supplied to the at least one steam turbine. A separate heat transfer medium is arranged in a heat exchange relationship with a heat consumer and is heated in a second apparatus by thermal energy extracted from the water/steam circuit at a plurality of extraction points each having a different temperature. The combination power station includes means for selectively connecting the second apparatus to the plurality of extraction points depending upon a thermal output and an inlet temperature required by the heat consumer.

Claims

1. A combination power station with power/heat cogeneration comprising:

at least one gas turbine driven by combustion gases from a combustion chamber and at least one steam turbine working in a water/steam circuit, the water/steam circuit converting water into steam in a first apparatus by hot combustion gases emerging from the at least one gas turbine and the steam being supplied to the at least one steam turbine, a separate heat transfer medium arranged in a heat exchange relationship with a heat consumer and being heated in a second apparatus by thermal energy extracted from the water/steam circuit at a plurality of extraction points each having a different temperature, and means for selectively connecting the second apparatus to the plurality of extraction points depending upon a thermal output and an inlet temperature required by the heat consumer.

2. The combination power station as claimed in claim 1, wherein the means for selectively connecting includes individual lines equipped with controllable valves for selectively connecting the second apparatus to the plurality of extraction points.

3. The combination power station as claimed in claim 2, wherein a valve control controls the controllable valves, and a temperature measuring point including a temperature measuring means is arranged at an outlet of the second apparatus in order to for determining a temperature of the heat transfer medium, and wherein a first input of the valve control is connected to the temperature measuring point.

4. The combination power station as claimed in claim 3, wherein a second input of the valve control is a desired value of the temperature of the separate heat transfer medium.

5. The combination power station as claimed in claim 1, wherein the second apparatus includes a condenser, and steam is extracted from the water/steam circuit at the extraction points, and wherein a condensate emerging from the condenser of the second apparatus is recirculated by a recirculation line into the water/steam circuit.

6. The combination power station as claimed in claim 5, wherein the plurality of extraction points includes a first extraction point for the extraction of a high pressure fresh steam, a second extraction point for the extraction of another high pressure steam and a third extraction point for a low pressure steam, and wherein a valve located at the first extraction point is a pressure reducing valve.

7. The combination power station as claimed in claim 5, wherein the second apparatus includes a preheater through which the condensate from the condenser flows, the preheater being arranged to precede the condenser and operates to preheat the separate heat transfer medium.

8. The combination power station as claimed in claim 7, wherein heated water extracted from the water/steam circuit is directed to flow through a line to the preheater.

9. The combination power station as claimed in claim 1, wherein the first apparatus includes a waste heat steam generator.

10. The combination power station as claimed in claim 9, wherein the waste heat steam generator includes an economizer, an evaporator and a superheater, and wherein water heated at the economizer is extracted from the water/steam circuit through a line in order to preheat the separate heat transfer medium.