Particle Size Distribution of Particulate Matter Emitted from a Layer Operation in Southeast U.S.

Abstract

This paper reports a field study on characterizing particle size distribution (PSD) of particulate matter (PM) emitted from a commercial layer operation in Southeast U.S. across three seasons from October of 2008 to April of 2009. Six low-volume (1m3/hr) total suspended particulate (TSP) samplers were used to collect PM samples in two high-rise layer houses. Laser diffraction particle size analyzer (LS13 320) was applied to measure PSD of PM samples collected by the TSP samplers. Results of the study indicate that TSP concentrations across the three seasons ranged from 888 to 5333 µg/m3. TSP concentration was affected by season, animal activity, floor and equivalent air flow rate factor. It was observed that TSP concentration in winter was higher than that in spring; concentration on the second floor was higher than that on the first floor; the more active the animals were, the higher the TSP concentration; the more the fans on, the lower the concentration. Compared with PM concentration, PSD (characterized by the mass medium diameter, MMD, & geometric standard deviation, GSD) was much less affected by season, animal activity, floor and equivalent flow rate factor. The MMD was affected by floor and equivalent flow rate factor, but the degree of affection was within the range of one standard deviation. Overall MMDs of PM samples collected in fall, winter and spring were 15.80±1.05µm, 17.13±0.81µm and 18.44±1.44µm, respectively. The difference of MMD among three seasons was within the range of one standard deviation. GSD was relatively constant and not affected by those factors. The overall GSD was 2.65±0.08.