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A combined cycle process that includes gas turbines, a steam turbine train, a heat recovery unit, and a gasification unit that produces low or mid BTU fuel gas from coal, lignite, coke, biomass, or other suitable hydrocarbon containing material wherein the fuel gas is burned in the heat recovery uni

A combined cycle process that includes gas turbines, a steam turbine train, a heat recovery unit, and a gasification unit that produces low or mid BTU fuel gas from coal, lignite, coke, biomass, or other suitable hydrocarbon containing material wherein the fuel gas is burned in the heat recovery unit at one or more points to increase steam rate to the steam turbine train.The fuel gas injection flow rates into the heat recovery unit are controlled to avoid exceeding peak temperatures in the heat recovery unit of about 2500 F.Optionally, the fuel gas from the gasification unit is cooled by transferring sensible heat to condensate from the steam turbine train to convert the condensate to high pressure steam for driving the steam turbine train.Optionally, a steam boiler unit is integrated into the combined cycle process to raise additional high pressure steam for the steam turbine train. The steam boiler feed water is condensate from the steam turbine train. The steam boiler produces saturated high pressure steam that is superheated in the heat recovery unit.

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1. A combined cycle process for generating electric power that includes: 1) a steam turbine train comprised of one or more steam turbines in series that has an upstream high pressure steam inlet and a downstream exhaust steam outlet, and that drives an electric generator, 2) two or more gas turbines

1. A combined cycle process for generating electric power that includes: 1) a steam turbine train comprised of one or more steam turbines in series that has an upstream high pressure steam inlet and a downstream exhaust steam outlet, and that drives an electric generator, 2) two or more gas turbines in parallel that each drive an electric generator, 3) a heat recovery unit, and 4) a gasification plant that produces a fuel gas stream selected from low BTU gas and mid BTU gas from a hydrocarbon containing material, the combined cycle process comprising the steps of:a. firing fuel gas in the gas turbines to drive their electric generator to produce electric power and emit a gas turbine combustion exhaust gas stream from the fired gas turbines;b. feeding a high pressure superheated steam stream to the upstream steam inlet to the steam turbine train and withdrawing a low pressure steam stream from the downstream steam outlet on the steam turbine train to produce electric power with the steam turbine train generator;c. condensing the low pressure steam stream from the steam turbine train to form a condensate stream;d. conveying the condensate stream to the heat recovery unit wherein the condensate stream is heated to form the high pressure super heated steam stream that is fed into the upstream steam inlet of the steam turbine train;e. combining the gas turbine exhaust gas streams and conveying the combined gas turbine combustion exhaust gas stream to the heat recovery unit wherein sensible heat is transferred from the combined gas turbine combustion gas stream to the condensate stream to convert the condensate stream to the high pressure superheated steam stream that is fed into the high pressure steam inlet to the steam turbine train;f. injecting the fuel gas that is produced in the gasification unit into the gas turbine combustion exhaust gas stream flowing through the heat recovery unit at a plurality of points spaced along the direction of flow of the combustion exhaust gas stream in the heat recovery unit.2. The process of claim 1 wherein the hydrocarbon containing material that is gasified in the gasifier to make the fuel gas is selected from among coal, lignite, coke, and bio-mass.3. The process of claim 1 wherein the fuel gas that is fed into the heat recovery unit is produced in a coke gasifier integrated into a fluidized-bed thermal cracking process.4. The process of claim 1 wherein a sulfur adsorbing solid material is fed into the gasification unit along with the hydrocarbon containing material that is gasified.5. The process of claim 4 wherein the sulfur adsorbing material is selected from limestone and dolomite.6. The process of claim 1 wherein the stream flow rates of the fuel gas streams injected into the gas turbine combustion exhaust gas stream flowing through the heat recovery unit are controlled so that the temperature of the gas turbine combustion exhaust gas stream does not exceed about 2500 degrees F.7. The process of claim 1 that includes the additional steps of extracting a steam side stream from a point on the steam turbine train, reheating that extracted steam side stream in the heat recovery unit, and feeding the reheated steam side stream back into the steam turbine train at a point downstream of the point from which the steam side stream was extracted.8. The process of claim 1 that includes a steam boiler unit that converts condensate to high pressure steam that is superheated and fed into the steam turbine train.9. A combined cycle process for generating electric power that includes: 1) a steam turbine train comprised of one or more steam turbines that has an upstream high pressure steam inlet and a downstream exhaust steam outlet, and that drives an electric generator, 2) two or more gas turbines each driving an electric generator and each emitting a gas turbine exhaust gas stream, 3) a heat recovery unit, 4) a gasification plant that produces fuel gas selected from a low BTU gas and a mid BTU gas from a hydrocarbon containing material, and 5) a fuel gas cooler that cools the product fuel gas by raising steam from condensate extracted from the steam turbine train, the combined cycle process comprising the steps of:a. firing fuel gas in the gas turbines to drive their electric generators to produce electric power, emitting a turbine combustion exhaust gas stream from each of the fired gas turbines;b. feeding a high pressure superheated steam stream to the upstream steam inlet of a steam turbine train, and withdrawing an exhaust steam stream from the downstream steam outlet from the steam turbine train;c. condensing the exhaust steam stream to form a condensate stream;d. dividing the condensate stream into a condensate stream A and a condensate stream B and conveying condensate stream B to the heat recovery unit;e. producing fuel gas in the gasification unit and conveying the fuel gas into the fuel gas cooler wherein the fuel gas is cooled to form a cooled fuel gas stream;f. conveying condensate stream A to the product cooler wherein condensate stream A is converted to a steam stream that is conveyed to superheat tubes in the heat recovery unit, thereby cooling the fuel gas to form the cooled fuel gas stream;g. combining the gas turbine combustion exhaust gas streams and conveying the combined gas turbine combustion exhaust gas stream to the heat recovery unit wherein sensible heat from the combined gas turbine combustion gas stream is transferred to the condensate stream B to convert the condensate stream B to high pressure super heated steam and to superheat the steam stream generated in the fuel gas cooler to form more high pressure super heated steam and combining the super heated high pressure steam streams to form the high pressure super heated steam that is fed into the upstream inlet to the steam turbine train as per step b;h. injecting the cooled fuel gas stream from the fuel gas cooler into the gas turbine combustion exhaust gas stream flowing through the heat recovery unit at a plurality of points spaced along the direction of the flow of the combustion exhaust gas stream in the heat recovery unit.10. The process of claim 9 wherein the hydrocarbon containing material that is gasified in the gasification unit to make the fuel gas is selected from among coal, lignite, coke, and bio-mass.11. The process of claim 9 wherein a sulfur adsorbing material that is fed into the gasification unit along with the material that is gasified.12. The process of claim 11 wherein the sulfur adsorbing material is selected from limestone and dolomite.13. The process of claim 9 that includes the additional steps of extracting a steam side stream from the steam turbine train, reheating the steam side stream in the heat recovery unit, and feeding the reheated side stream into the steam turbine train at a point downstream of the extraction point.14. The process of claim 9 that includes the additional step of treating the cooled fuel gas stream in a sulfur removal unit to remove sulfur compounds from the cooled fuel gas stream.15. The process of claim 9 that includes a steam boiler unit that converts condensate to high pressure steam that is superheated in the heat recovery unit and fed into the steam turbine train.16. The process of claim 9 wherein the fuel gas that is fed into the heat recovery unit is produced in a coke gasifier that is integrated into a fluidized-bed thermal cracking process.