The report gives results of a study to determine if and when the application of NOx flue gas treatment (FGT) technology will be necessary in the U.S. It addresses factors that will influence the levels of NOx emission control needed to comply with both existing and future NOx standards. Topics treated include NOx emission sources, atmospheric transport and reactions, air quality trends, regulations, and control strategies, and FGT methods. The study concludes that the number of Air Quality Control Regions (AQCRs) with NOx compliance problems can be expected to increase significantly in the next decade. It further concludes that progressively larger reductions in NOx emissions will be required in order to attain and maintain compliance in 'problem' AQCRs. The study does not establish conclusively whether or not FGT will be required. However, current trends indicate that FGT may be necessary in the future to achieve compliance with NOx standards in certain AQCRs. This conclusion follows from the regionally specific nature of U.S. NOx compliance problems, as well as uncertainties concerning both future NOx emission reduction requirements and the ultimate effectiveness of alternative NOx control methods, such as combustion modification.

Prepared for Environmental Protection Agency, Office of Research and Development. Contract no. 68-02-2608, task no. 13, program element no. 1NE624. November 1978. Includes bibliographical references.