The influence of dust particules on odors coming from livestock building was evaluated in laboratory using full-scale installations. The ventilation air coming from four nursery rooms ventilated separately passed through chopped cornstalks and corncobs used as substrate in four biofilters. Samples of the ventilation air before and after the biofilters treatments were taken for dust analysis (total dust concentration, the particule distribution) and odor threshold determination by olfactometry. The results obtained showed that the odor threshold could be reducted to up to 76% with particules removal of nearly 100%. These results agreed with previous work suggesting that dust particules are odor carrier as the odor compounds probably adhere to the particles. The biofilters used were effective in removing particules in excess of 10 microns.

The odor emission reduction by dust removal is very interesting. This work however doesn’t give any information about the investment and operation cost of such biofilters as booster fans have to be used to push the ventilated air through the filters. Dust removal would be even more interesting if the dust inside the building could be controled to improve the inside conditions for swine and workers.