Technical Bulletin No. 0094: A Study of Particulate Size Distribution in Emissions from Controlled Sources in the Kraft Process (AQTB)

There is an increasing level of interest in the presence of small particles in the atmosphere and the extent to which existing control technology is demonstrated to control fine particle emissions. The concern for small particles, those less than 2.5 to 3 microns, in the ambient air, is related to their size since they have been demonstrated to be of respirable size and capable of reaching the lower lung. The physiological response to inhalation of small particles differs widely, however, depending on their chemical composition. There is mounting scientific evidence that acid and heavy metal sulfate aerosols are the dominant health related fine particles in the ambient air. Plume appearance, and more recently as a result of the Clean Air Act Amendments of 1977, visibility reduction caused by fine particles, those of a size less than 1 micron, pose a series of yet unanswered scientific problems. The work reported in this technical bulletin is an outgrowth of agency interest in visibility reduction. The contents of the bulletin served as the industry response for information requested by the Oregon Department of Environmental Quality on fine particle emissions from the kraft industry in that state.