Patent ID: 8117821

Claim:
A low BTU fuel based combined-cycle power plant, comprising: a gas mixing unit that mixes by-product off-gases, wherein the by-product off-gases include blast furnace gas and coke oven gas; a fuel gas compressor coupled to the gas mixing unit that pressurizes the mixture of by-product off-gases; a gas turbine fueled by the pressurized mixture of by-product off-gases from the fuel gas compressor, the gas turbine comprising a compressor; a combustor that receives air from the compressor and the pressurized mixture of by-product off-gases from the fuel gas compressor for combustion thereof; and a turbine that expands hot gas generated from the combustion of the air from the compressor and the pressurized mixture of by-product off-gases from the fuel gas compressor; a fired heating unit that receives a diverted portion of the by-product off-gases and a bleed-off of compressed air flow from the gas turbine compressor for combustion thereof, wherein the diverted portion of the by-product off-gases received by the fired heating unit comprise a portion of the blast furnace gas, the combustion of the diverted portion of the by-product off-gases and the bleed-off of compressed air flow in the fired heating unit producing a high temperature flue gas; and a performance heating unit that heats the pressurized mixture of by-product off-gases from the fuel gas compressor with the high temperature flue gas produced from the fired heating unit prior to entering the gas turbine combustor, wherein exhaust gas from the performance heating unit is mixed with exhaust gas from the gas turbine.