By Jeff Mulhollem
A scientist in Penn State’s College of Agricultural Sciences has received a $300,000 grant from the U.S. Department of Agriculture to lead a team conducting research on using biofilters to mitigate methane from enteric emissions produced in livestock facilities.
Juliana Vasco-Correa, assistant professor of agricultural and biological engineering, and colleagues will use the three-year award from the USDA’s National Institute of Food and Agriculture to fund a study of the causes of nitrous oxide formation in biofilters used for methane abatement of enclosed livestock systems.
Biofilters are a promising solution for mitigation of methane emissions from agricultural systems, according to Vasco-Correa, but the potential generation of the potent greenhouse gas nitrous oxide in these biofilters can hinder their applicability. The project’s objectives are to test the effects of ammonia concentration in the inlet air, the moisture content, and the packing media compaction on biofilter performance and nitrous oxide formation.
The researchers’ central hypothesis is that these properties have a strong influence on the production of nitrous oxide in biofilters, and that the understanding of these mechanisms can be manipulated to help control the production of nitrous oxide in the future, according to Vasco-Correa.
“The results of this project will allow us to propose methods to regulate nitrous oxide formation in methane biofilters and will provide a strong foundation for future biofilter designs and specifications,” she said. “That will make us competitive for future funding to develop economically feasible methane biofiltration systems for livestock facilities.”
An engineered system developed by Vasco-Correa removes gas waste from livestock facilities and she believes the biofilter could be made completely from biobased materials and commercialized in the marketplace. The main product from the biofilters is the methane mitigation, which is an ecosystem service in growing demand.
“These biofilters will contribute to the long-term economic and environmental sustainability of livestock production and processing systems,” she said.
In the study, Vasco-Correa explained, the researchers will perform a series of experiments to evaluate the effect of key process conditions and packing media on the production of nitrous oxide in methane-oxidizing biofilters. They will use a biofilter system previously devised by Vasco-Correa’s research group. The system consists of a bank of laboratory scale biofilter columns connected to a gas-dilution system to control inflow gas composition and flowrate by mixing methane, ammonia and air.
A humidifier will be used to control moisture content in the inlet gas. The standard biofilter packing media will consist in a 50:50 mix of compost obtained from the Penn State Organic Materials Processing Center facility mixed wood chips provided by the Penn State Office of the Physical Plant grounds maintenance team.
Also on the research team are Mary Ann Bruns, professor of soil microbiology and biogeochemistry, Department of Ecosystem Science and Management; Lauren Greenlee, associate professor, chemical engineering, Department of Chemical Engineering; and Tom Richard, professor of agricultural and biological engineering, Department of Agricultural and Biological Engineering.
Source : psu.edu