Design and analysis of a pilot scale biofiltration system for odorous air

Three pilot-scale biofilters and necessary peripheral equipment were built to clean odorous air from the pit of a swine gestation building at North Ca rolina State University. A computer measured temperatures, flow rates, and pressure drops. It also controlled and measured the moisture content of a b iofilter medium comprised of a 3:1 mixture of yard waste compost to wood ch ips mixture (by volume). The system was evaluated to ensure that the biofil ters would be useful for performing scientific experiments concerning the r eduction of swine odor on future research projects. The capability of the b iofilters to remove odor was measured using a cotton swatch absorption meth od and an odor panel. The average odor reductions measured by odor intensit y, irritation intensity, and unpleasantness for five tests were 61%, 58%, a nd 84%, respectively. No significant differences in odor reduction performa nce were found between the biofilters.