초록 ▼

A combined cycle power generation plant includes a boiler for producing steam, the boiler including a furnace for combusting first fuel to produce flue gas, a back-pass for receiving the produced flue gas and a flue gas duct for passing the flue gas from the back-pass to the environment, a process g

A combined cycle power generation plant includes a boiler for producing steam, the boiler including a furnace for combusting first fuel to produce flue gas, a back-pass for receiving the produced flue gas and a flue gas duct for passing the flue gas from the back-pass to the environment, a process gas supply for supplying processed gas to the furnace, a steam turbine for receiving and being driven by the steam to generate power, a combustor for combusting a second fuel to produce exhaust gas, a gas turbine for expanding the exhaust gas from the combustor to generate power and for passing the exhaust gas to the process gas supply. The boiler is designed to provide effective steam production and low emissions to the environment in first operating conditions of the combustor when using exhaust gas alone or as a major portion of process gas being supplied to the boiler.

대표청구항 ▼

1. A method of operating a combined cycle power generation plant, said method comprising:providing a boiler having a furnace for combusting a first fuel to produce flue gas and for producing steam; conducting the flue gas through a flue gas duct to the environment; supplying process gas to the furna

1. A method of operating a combined cycle power generation plant, said method comprising:providing a boiler having a furnace for combusting a first fuel to produce flue gas and for producing steam; conducting the flue gas through a flue gas duct to the environment; supplying process gas to the furnace; driving a steam turbine by the steam to generate power; combusting, in a combustor, a second fuel to produce exhaust gas; expanding the produced exhaust gas in a gas turbine to generate power; passing the exhaust gas from the gas turbine to the process gas supply; recirculating a portion of the flue gas from the flue gas duct to the process gas supply; controlling the rate of recirculation of the flue gas by a first controller; supplying fresh air to the process gas supply; controlling the rate of fresh air supply by a second controller; supplying a selected amount of first fuel to the furnace; supplying a selected amount of second fuel to the combustor; measuring the operating conditions of the combustor, wherein the boiler is designed to provide, in first operating conditions of the combustor, effective steam production and low emissions when the first and second controllers minimize the rate of flue gas recirculation and fresh air supply, respectively, and the exhaust gas is used alone or as a major portion of the process gas; controlling, in conditions other than the first operating conditions of the combustor, the first and second controllers to obtain at least nearly as effective steam production and as low emissions as in the first operating conditions; and basing the control of the first and second controllers on the measured operating conditions in said step of controlling in conditions other than the first operating conditions.