초록 ▼

In a combined cycle power plant operable on either gas or liquid fuels maximum design efficiency is achieved at the lowest HRSG stack temperatures. This can be optimized for operation on natural gas but for liquid fuel operation consideration must be given to sulfur cold end corrosion. A feedwater r

In a combined cycle power plant operable on either gas or liquid fuels maximum design efficiency is achieved at the lowest HRSG stack temperatures. This can be optimized for operation on natural gas but for liquid fuel operation consideration must be given to sulfur cold end corrosion. A feedwater recirculation loop is shown which allows for selectively heating feedwater during liquid fuel operation and for non-heating during gas operation. Economizer recirculation is also introduced to prevent economizer steaming.

대표청구항 ▼

A dual fuel combined cycle power plant including at least one gas turbine and at least one steam turbine thermally interconnected through at least one heat recovery steam generator; the combined cycle power plant selectively operable on liquid or gas fuels and including an improved feedwater recircu

A dual fuel combined cycle power plant including at least one gas turbine and at least one steam turbine thermally interconnected through at least one heat recovery steam generator; the combined cycle power plant selectively operable on liquid or gas fuels and including an improved feedwater recirculation loop connecting the steam turbine and heat recovery steam generator wherein the improvement comprises: a heater loop including at least one feedwater heater connected to receive extraction steam from the steam turbine and including an upstream and downstream feedwater flow isolation valve; and, a bypass loop including an upstream and downstream feedwater flow isolation valve, the heater loop and bypass loop being connected in parallel; and, the heater loop valves open during liquid fuel operation; and, the bypass loop valves open during gas fuel operation.