SIMPLIFYING FUEL SYSTEM FOR HOT START OPERATION OF GAS TURBINES
Publication Date: 2012-Dec-13
The IP.com Prior Art Database
This publication relates to a method of simplifying fuel system for startup/hot start operation of gas turbines. Turbines using syngas for operation require a higher calorific fuel for the startup operation, due to combustion efficiency considerations. This necessitates a system of piping another fuel such as natural gas or synthetic gas to the turbine for startup. The new method involves addition of a small scale methanation scheme within the existing IGCC reference plant. A portion of the existing syngas inlet is converted to SNG fuel using a methanation reactor and the SNG so produced is used for startup/hot start operations in the gas turbines. The method enables elimination of capital costs toward piping and associated machinery for natural gas and also improves plant safety.
This publication describes a method of simplifying fuel system for hot start operation of gas turbines. Syngas is used as a primary fuel source in IGCC applications for operation in gas turbines. The current methods involve using an alternate/secondary fuel source like natural gas or distillate fuel in the process of startup/ hot start operation of gas turbines for IGCC (Integrated Gasification Combined Cycle) applications.
During the startup operation for up to 30% load the combustion efficiency is low and higher H2 content of >5% in the inlet results in incomplete combustion and hydrogen accumulation in the combustion chamber, which could cause a severe explosion of hydrogen. Even if explosion does not occur, it could result in unstable combustion dynamics in the chamber at higher loads. Syngas is therefore not preferred for startup operation.
This problem is addressed presently by using a natural gas pipeline and compressors. A new method is proposed in which SNG (synthetic natural gas) will be manufactured within the site at pressure, which eliminates pipe lines, compressors and startup fuel heaters.
BRIEF DESCRIPTION OF DRAWINGS
Simplifying fuel system for hot start operation of gas turbines is disclosed in which:
Fig. 1 shows an overview of the method.
The method used to simplify fuel system hot start operation of gas turbines is shown schematically in Fig. 1. The method involves addition of a small scale methanation scheme within the existing IGCC reference plant. As shown in Fig. 1, a portion of the existing syngas is profitably converted to SNG fuel using a methanation reactor and the SNG so produced is used for startup/hot start operations in the gas turbines.