Method of operating a power plant with recycled CO2

• US 6,269,624 B1
• Filed: 04/27/1999
• Issued: 08/07/2001
• Est. Priority Date: 04/28/1998
• Status: Expired due to Term

• Current Assignee: General Electric Technology GmbH (GE Aerospace)
• Original Assignee: Asea Brown Boveri AG (ABB Limited)
• Inventors: Wettstein, Hans, Frutschi, Hans Ulrich
• Primary Examiner(s): Casaregola, Louis J.
• Application Number:
  US09/300,276
• Time in Patent Office: 833 Days
• Field of Search: 60/390.2, 60/390.7, 60/393.1, 60/395.2
• US Class Current: 60/783
• CPC Class Codes: F01K 21/047 having at least one combustion gas turbine
• CPC Class Codes: F02C 1/06 using reheated exhaust gas F02C1/08 takes precedence
• 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: F05D 2260/211 by intercooling, e.g. during a compression cycle
• CPC Class Codes: Y02E 20/34 Indirect CO2mitigation, i.e. by acting on non CO2directly related matters of the process, e.g. pre-heating or heat recovery

Abstract

In a method of operating a power station plant with a closed or virtually closed CO₂ process, a fuel quantity (21) and oxygen (18) required in this regard for the oxidation are introduced into the cycle for the internal combustion. A recuperator (8) acts on the downstream side of a turbine (2) belonging to the power station plant, at least one heat sink (24) operating downstream of this recuperator before the cycle medium (6) flows back into a compressor (1) which likewise belongs to the power station plant. A partial quantity of the compressed cycle medium (10) is directed into a condensing plant, the liquid CO₂ formed here being disposed of in the best possible way.

Claims

1. A method of operating a power station plant, the power station plant having a compressor unit, at least one combustion chamber and at least one turbine, and a recuperator downstream from the turbine, the method comprising:

supplying a cycle medium containing CO₂ and a fuel and the oxygen required for the oxidation thereof in the combustion chamber,

conducting the cycle medium from the low-pressure side of the turbine to the recuperator,

passing the medium through a heat sink downstream of the recuperator, the heat sink being operated at least at ambient temperature,

feeding the medium back into the compressor unit,

withdrawing a portion of the cycle medium downstream of the compressor and upstream of the recuperator and conducting the withdrawn portion into a condensing plant, and

controlling the charging pressure of the cycle processs by extracting any excess cycle medium.

2. The method as claimed in claim 1, wherein the step of withdrawing a portion of the cycle medium, corresponds to a certain separation rate of CO₂ with which the degree of charging of the cycle process and its output are correspondingly controlled.

3. The method as claimed in claim 1, wherein gases produced in the cycle process are separated from the condensing plant at the same time.

4. The method as claimed in claim 1, wherein a CO₂ quantity is directed into the cycle in order to start the process.

5. The method as claimed in claim 4, wherein the CO₂ quantity is directed into the thermally treated exhaust gases on the low-pressure side.

6. The method as claimed in claim 1, wherein a quantity of the cycle medium is branched off on the low-pressure side from the recuperator, or downstream of the recuperator in order to operate an expander.