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Trends in NOx Emissions

AUTHOR: Lesley Sloss
DATE: April 1998

Coal utilisation is one of the sources of NOx emissions to the atmosphere. Emissions of NOx play an important role in many environmental issues, including acidifcation, eutrophication, ozone formation and hence the greenhouse effect.

Information published since 1991 is reviewed. This report covers NO and NO2, but excludes N20 which is an oxide of nitrogen with a quite different role in the atmosphere. Glkobal and regional emissions of NOx are collated and the relative contributions of coal utilisation compared with emissions from other human activities and from natural sources are examined. The study includes a brief review of emission standards and the associated methods used to estimate emissions of NOx from coal utilisation.

There has been legislation to limit NOx emissions in some countries for many years and new legislation is continually being introduced. The effects of this legislation and the introduction of NOx abatement and control on the trends in NOx emissions and concentrations is examined.