Modified gas turbine system with advanced pressurized fluidized bed combustor cycle

A gas turbine system comprising:

• a gas turbine including a compressor for compressing air, a combustor in flow communication with said compressor for receiving a first portion of the air compressed by said first compressor, a turbine for expanding a hot working gas flowing thereto from said combustor, and a flow path for conducting exhaust gas from said turbine to a heat recovery steam generator;
• a second source of compressed air;
• an extraction air flow path for a second portion of said air compressed by said first compressor;
• an auxiliary air flow path for compressed air from said second source of compressed air;
• a pressurized fluidized bed combustor (PFBC) operatively coupled to at least one of said extraction air flow path and said auxiliary air flow path, for receiving compressed air therefrom for burning a solid fuel to produce hot gas;
• an expander turbine;
• a hot gas flow path for conducting said hot gas from said PFBC to said expander turbine for generating power from said hot gas;
• a carbonizer for converting a carbonaceous fuel to a carbonaceous char and a fuel gas, said carbonizer being operatively coupled to at least one of said extraction air flow path and said auxiliary air flow path, a boost compressor being disposed intermediate said carbonizer and said combined compressed air flow path for further compressing compressed air received from said at least one air flow path for delivery to said carbonizer;
• a flow path for supplying said carbonaceous char produced by said carbonizer to said PFBC thereby to define a fuel supply to said PFBC;
• and
• a fuel gas flow path for conducting said fuel gas from said carbonizer to said combustor of said gas turbine for combustion to produce said hot working gas.

A method for generating electrical power utilizing a compressor, a fuel gas combustor, a combustion turbine, a pressurized fluidized bed combustor (PFBC), an expander turbine and a solid fuel, comprising the steps of:

• compressing air in said compressor and flowing said compressed air toward said fuel gas combustor;
• extracting a portion of said compressed air;
• providing a second source of compressed air;
• fluidizing and burning said solid fuel in said PFBC using compressed air from at least one of said extracted portion and said second source, thereby producing hot gas;
• and
• expanding said hot gas in said expander turbine, thereby producing power and expanded gas.