Evaluation of a modular, interior-mounted biofilter


Project Leader:  Danny Mann

Executive Summary:

Biofilters that are not fully integrated with the barn from which odor is being generated often will operate at less than peak efficiency.  In this project, a biofilter was situated inside a hog barn with the intention of reducing odourous emissions from the hog barn by improving the quality of air inside the barn.  The biofilter consisted of 8 removable and replaceable cartridges,each 50 cm wide, 100 cm deep and 100 cm tall.  Surface velocity was measureed to 0.15 m/s on average, just slightly lower than the 0.20 m/s surface velocity predicted by design calculations.  A flaw in the design of the biofilter prevented it from being irrigated as intended.  Concentrations of hydrogen sulfide, ammonia, carbon dioxide, and odor were monitored in both a biofilter room and a control room, each initially stocked with the same number of pigs.  The pigs were approximately of the same age and weight.  Odor concentration was measured by the use of an olfactometer and trained panelists.  Concentrations of hydrogen sulfide, ammonia, and carbon dioxide were monitored by using a Jerome meter, color-coded litmus paper, and a digital carbon dioxide meter, respectively.  The results showed no significant differences in the concentrations of hydrogen sulfide, ammonia, carbon dioxide, or odor present in the two rooms.  The failure of the biofilter can be attributed to the design flaw which prevented irrigation of the biofilter media.

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