Patent ID: 7114351

Claim:
An improved efficiency, reduced carbon dioxide emissions method for providing internally generated electric power for refrigerant compression and shared electrical power for a light hydrocarbon gas liquefaction process, the method consisting essentially of: a) providing at least a portion of the electrical power for the refrigerant compression and for the light hydrocarbon gas liquefaction process from at least one electrical generator driven by at least one fossil fuel fired turbine, the at least one fossil fuel fired turbine being fueled by a compressed air stream and a light hydrocarbon gas stream and producing a high-temperature, high-pressure gas stream to power the turbine and discharge a high-temperature exhaust gas stream; b) passing the high-temperature exhaust gas stream to heat exchange with water or low-pressure steam to produce a higher pressure steam stream; c) passing the higher pressure steam stream to a steam turbine to drive at least one energy recovery electrical generator to produce electrical power; d) compressing a low-pressure refrigerant to an increased pressure in at least one refrigerant compressor driven by an electric motor powered by electrical power generated by the at least one electrical generator or the at least one energy recovery electrical generator; all of the required electrical power for the refrigerant compression and shared electrical power for the light hydrocarbon gas liquefaction process being supplied by the at least one electrical generator and the at least one energy recovery generator; and, e) providing and maintaining in condition for quick substitution for the at least one generator driven by the at least one fossil fuel fired turbine, at least one standby generator driven by at least one standby fossil fuel fired turbine.