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FOR IMMEDIATE RELEASE CONTACT: Odor Primary Factor Limiting Livestock Expansion DES MOINES, Iowa (June 7, 2007) – The number one factor preventing expansion of any livestock operation is odor, whether it be dairy, swine, poultry or beef, said Dr. Dick Nicolai, Associate Professor and Extension Specialist at South Dakota State University. The good news is that odor shouldn’t stand in the way of establishing or expanding a livestock operation if producers take a scientific approach, use technology such as biofilters and covered manure storage units like a Slurrystore, and develop good community relations. Dr. Nicolai spoke on “Swine Odor Control Techniques” at World Pork Expo during the Environmental Information Center session on Ag Waste and Nutrient Management, which was sponsored by Engineered Storage Products Company, manufacturers of Slurrystore® systems. Known as the “Father of the Biofilter,” Dr. Nicolai also is president and co-owner of a 1,500-head farrow-to-wean operation new Hector, Minnesota. Dr. Nicolai lectured on all aspects of odor control in swine -- measuring odor, how odor travels from one point to the next, how it travels through a building, air dispersion and how to enhance it, and techniques to mitigate odor and release. “The only way to measure odor is the human nose,” said Dr. Nicolai. “There is no instrument to measure odor. That makes odor a subjective measurement more than an objective one, although there are techniques now in place that make the measurement more objective through human training. We need to remove emotion and substitute it with science” when considering if a unit will emit an annoying level of odor detectable by its neighbors. For his research, Dr. Nicolai employs people trained to detect the “odor threshold” and “odor intensity,” as well as “characteristics” of various odors. He compares odor detection to turning up the volume on a radio – at first you don’t hear it, then you do – detection – and as the volume increases, so does its intensity until a threshold is reached when it is “too loud” and becomes offensive to others. Odor management begins with the siting of the facility, Dr. Nicolai explained. Choosing the best location – based on topography, wind and weather patterns, proximity to neighbors, the orientation of the building, etc. – is the first line of defense. “Then, if you still have a problem, you can move into areas such as biofilters, covers on outside storage systems, and other technologies to reduce the amount of emissions.” Dairy and beef manure stored in a Slurrystore will crust over. The unit also has a “chimney effect” that sends odors up into higher air flows where they are less noticeable. Biofilters for Better Odor Control Sources such as manure, or a dead animal give off volatile organic compounds. Microorganisms in the soil use these compounds as food and convert it to carbon dioxide and water. “Taking that basic principle, we make a bed of wood chips, and we pass the air through this bed and let the microorganisms do their thing.” A horizontal biofilter, for example, is outside the facility adjacent to the exhaust fans of the building. The exhaust air is directed down to an air plenum beneath a 14 to 20 inch deep bed of wood chips, which may be 30 feet wide by the length of the building. Underneath the wood chip bed may be shipping pallets, for instance, for an air plenum and support. The air is passed through the wood chips coated with microorganisms living in a water biofilm on each chip. As the air passes through the wood chips, it is absorbed into the biofilm, degasses, and the microorganisms then process the biomatter to give off carbon dioxide and water. “The entire structure is relatively inexpensive,” Dr. Nicolai said. “It is very effective when maintained properly, and you get 80 to 95 percent odor reduction.” The basics of swine biofiltration can be found at the SDSU web site at: http://maverick.sdstate.edu/users/nicolaid/Biofilters/Biofilter%20Design%20Spreadsheet.xls Steps Swine Producers Can Take About Odor When Expanding
“The odor issue is solvable,” Dr. Nicolai concluded. “It does not have to be a hindrance. There are technologies out there. We are continuing to develop new technologies to mitigate the odor. |