This article was written collaboratively by Erin Cortus (former SDSU Extension Environmental Quality Engineer) and Kevin Janni, University of Minnesota.
Biofilters are used to treat odorous air from mechanically ventilated livestock barns and manure storage units. Odorous air is blown through a porous media—wood chips are commonly used in the Midwest—where microorganisms and fungi grow and remove the odorous gases. Well-managed biofilters can reduce odor emissions by up to 95 percent.
Whether you are considering a biofilter as an odor reduction method for your facility, or simply want to better understand how they work, a short 10-min video provides an overview on their application, typical designs, effectiveness, cost, and management considerations. The video can be accessed through YouTube or by viewing the embedded video below. This video and others are also available on the eXtension.org page Manure Covers and Biofilters for Managing Odor and Air Emissions.
For more in-depth information on biofilters, a factsheet co-written by retired South Dakota State University professor Dick Nicolai summarizes the science, design parameters, costs and management considerations. The factsheet Biofilters for Odor and Air Pollution Mitigation in Animal Agriculture is available through eXtension.org.