Gas and Odor Emissions from Swine Building Materials

Gas and odor emissions produced by twelve different materials commonly used in a typical swine building were measured. After being submerged for 72 hours in swine manure, material samples were thereafter randomly introduced in twelve monitoring testing chambers. The stainless steel testing chambers allowed a precise control of the interior temperature, relative humidity, air speed and airflow. Samples remained in chambers for a 24-hour desorption period during which the emission of the following gas NH3, CH4, N2O and CO2 were measured continuously. At the end of the desorption period, the air in each testing chamber was sampled in a large tedlar bag for the determination of the odor concentration with a dynamic olfactometer using a human panel. Olfactometry results showed that plastics, like plastisol and HDPE, and plywood were the most odorous materials followed by concretes, PVC, galvanized steel and cast iron. Over the period of desorption, NH3 emissions were relatively constant. The highest NH3 emissions, was produced by the 30 MPa normal concrete, it reached a maximum of about 175 mg/m2/h. CO2 emission were similar for all materials. It increased linearly with time.