Gas Turbine Handbook : Principles and Practices

Gas Turbine Exhaust Treatment 131
Chapter 9
Gas Turbine
Exhaust Treatment
To one degree or another we all live with air pollution. The
wind and rain continuously dilute and remove these polluting
contaminants (although to some extent this merely
transforms them from air pollution to water pollution). Awareness
of air pollution is greater around commercial and industrial fossil
fuel burning plants and in our large cities worldwide. Air pollution
is a problem because, in sufficient quantities, it is detrimental to our
health and that of our children. We have identified the components
of air pollution as hydrocarbons, carbon monoxide, sulfur oxides,
and nitrogen oxides. We have also determined that, on a worldwide
basis, nature produces more pollution than man. As shown in Table
9-1 nature produces more than three times the amount of sulfur
oxides and ten times the amount of nitrogen oxides than does man.
This table is a compilation of the annual emission rates of hydrocarbons,
carbon monoxide, sulfur compounds, and nitrogen oxides for
which the world-wide studies of sources, concentrations, and sinks
have been made.
While this table shows that natural sources exceed man-made
sources, locally—where most man-made pollutants are produced—the
picture may be entirely different. An example of this is in our large
cities where the automobile makes a large contribution to the amount
of pollution present. When we look at the amount of contaminant generated
by each fossil fuel burning piece of equipment, and the number
and location of such equipment, we begin to understand that we can
and must improve our own environment.
The products of combustion from gas turbines burning hydrocarbon
fuels are detailed in Table 9-2.
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