A method of using internal combustion engine exhaust in a combined cycle
power plant is disclosed, wherein the quality and distribution of exhaust
to the boiler space of a steam generated electric power plant is
controlled to achieve greater system efficiencies, and wherein exhaust
pollutants are reduced. Outside air is blended only with that portion of
the exhaust that passes through the burner ports as secondary or higher
level combustion gas. The remainder of the exhaust is provided to the
boiler space by a route other than through the burner. The highest overall
system efficiencies are achieved where the amount of outside air blended
with the portion of exhaust that passes through the burner is such that
the blend contains about the minimum amount of oxygen required for
complete and stable combustion of the selected fuel, where a substantial
percentage of the total exhaust is routed to the boiler space by a route
other than through the burner, and where the amount of fuel is sufficient
to achieve a desired boiler entering temperature upon its combustion.
Pollutants are reduced by combinations of staged reburning, Selective
Non-Catalytic Reduction, and Selective Catalytic Reduction processes
applied at various points along the combustion and exhaust path.
