US Patent 11047307 Hybrid expander cycle with intercooling and turbo-generator

A gas turbine engine system includes a gas turbine engine and a fuel turbine system. The gas turbine engine includes a heat exchange system configured to transfer thermal energy from a first compressed air flow and an exhaust gas flow to a fuel to produce a gaseous fuel. The fuel turbine system includes a fuel turbine fluidly coupled to the heat exchange system and a combustor of the gas turbine engine, and a fuel pump fluidly coupled to the heat exchange system and configured to be driven by the fuel turbine. The fuel turbine is configured to extract energy from expansion of the gaseous fuel to produce the gaseous fuel at a lower pressure for delivery to the combustor.