Gas Turbine Handbook : Principles and Practices

134 Gas Turbine Handbook: Principles and Practices
compounds (such as hydrogen cyanide). The amount of fuel bound
nitrogen in petroleum liquid fuels depends on the source crude oil
and the refining process. Properties of liquid and gaseous fuels are
detailed in Appendix C7 and C8.
In general, nitrogen oxide emissions increase in direct proportion
to the increase in combustion temperature as shown in Figure
9-3. Modifications to the combustor design of a number of gas turbine
models have already demonstrated that significant reductions in NO x
are achievable.
Another factor influencing the degree of pollutant level in the
atmosphere is the time necessary for each constituent to be consumed
by the various mechanisms available—called sinks. As Table 9-3
shows, nitrogen oxides last up to 5 days while carbon monoxide can
last up to 3 years.
Carbon Monoxide (CO)
Coal Gas (Air-blown)
Coal Gas (Oxygen-blown)
Ethane (C 2
H 6
)
Gas from Biomass
Gob Gas (Coal Mine)
Hydrogen (H 2
)
Methane (CH 4
)
Natural Gas (Pipeline)
Natural Gas (Raw)
Propane (C 3
H 8
)
Refinery Waste Gas
Town Gas
0 0.5 1.0 1.5 2.0 2.5
Figure 9-1. Courtesy of Solar Turbines Incorporated. Comparison
to methane of the relative Thermal NO x
produced by various fuel
gases.