AMMONIA DISTRIBUTION IN A PIT-VENTILATED CONFINEMENT BUILDING: ONE-HALF SCALE MODEL STUDY

Abstract

A one-half scale model of a pit-ventilated swine confinement barn was used to study the effects of buildingdesign and management factors on the distribution of ammonia in the airspace. Two slat orientations, two manure depths(full and empty), and two ventilation rates, representative of winter conditions, were compared. As expected, theventilation rate was a major factor in determining average levels of ammonia in the airspace. Manure depth significantlyaffected ammonia levels and gas distribution in the airspace above and below the slatted floor. Large stagnant regionswere observed in the manure pit head-space for a nearly empty manure pit. Floor slat orientation did not appear tosignificantly affect average ammonia levels or the distribution of ammonia in the airspace, although some effects mayhave been present at the higher ventilation rate tested.