The air quality program focuses mainly on emissions from forest products manufacturing facilities. NCASI conducts evaluations of stack sampling and analytical methods to determine if they are capable of accurately characterizing emissions from sources commonly found at pulp and paper mills, panel plants, and lumber mills. When suitable measurement techniques are lacking, NCASI develops and validates methodologies that can be used on industry emission sources.

Another key aspect of NCASI’s air quality program is characterization of source emissions and identification of factors affecting these emissions. NCASI carries out field studies at member company mills to obtain essential emissions data. These data are often supplemented with member company-generated testing information to broaden the available data base.   This data base can be  used to develop an  understanding of

factors affecting emissions by analyzing the sampling data in conjunction with relevant equipment design and associated process operating information. Results from these investigations are widely used by the industry for evaluating the performance of air pollution control technologies, for examining emission reduction options through process modification, for preparing air quality permit applications, for meeting emission reporting obligations, and for assessing the impact of emerging federal, state or provincial emission regulations.

Current investigations are addressing NOx, particulate, reduced sulfur compounds, and volatile organic compounds. For example, two current studies examine NOx emissions from bark-fired boilers and wood-fired combustion sources at panel plants, and their relationship to the nitrogen content of the fuels being burned. Over the last three years, NCASI has also examined NOx emissions from lime kilns, kraft recovery furnaces, kraft mill thermal oxidizers, and various combustion devices at kraft mills burning stripper off-gases containing ammonia. Measurement of total particulate matter, PM10, PM2.5, and condensable particulates is an active area of research. Studies are in progress to determine emission rates from boilers, recovery furnaces, and lime kilns equipped with dry control devices of varying efficiencies. Evaluations of methods for measuring particulate emissions from wet sources and sources with extremely low emission rates (e.g., paper machines) are also in progress. A major investigation of reduced sulfur compound releases from kraft mill wastewater treatment systems was initiated in 2004; the study involves sampling of liquid effluents, primary and secondary sludge, and ambient air in the vicinity of clarifiers, aeration basins, and polishing ponds. Several projects related to total and selected individual volatile organic compounds (VOCs) are being conducted in 2004. Much of this work will focus on various measurement methods that can be used on panel plant emission sources, particularly press vents and wood furnish dryers. In recent years, NCASI has studied VOC emissions from a wide array of panel plant emission sources as well as from lumber kilns.