@article{hood_shah_kolar_li_stikeleather_2015, title={Biofiltration of Ammonia and GHGs from Swine Gestation Barn Pit Exhaust}, volume={58}, ISSN={2151-0032 2151-0040}, url={http://dx.doi.org/10.13031/trans.58.10949}, DOI={10.13031/trans.58.10949}, abstractNote={ Abstract. Livestock barn emissions can affect public health, the environment, and quality of life. While these emissions can be mitigated using several methods, exhaust air treatment may be required in some situations. Biofiltration is one of the most cost-effective exhaust air treatment methods. In a biofilter, polluted air passes through a moist medium (e.g., compost) where the water-soluble gases are dissolved and then degraded by microorganisms into harmless or less harmful compounds. In this study, a downflow biofilter using a compost and wood chip medium was evaluated over summer, fall, and winter (August 2010 to January 2011) for its ability to mitigate emissions of ammonia (NH3) and three greenhouse gases (GHGs): methane (CH4), nitrous dioxide (N2O), and carbon dioxide (CO2). Biofilter medium properties were analyzed at the beginning and twice during the study. Changes in medium properties and CO2 data indicated greater heterotrophic microbial activity during summer through fall and greater autotrophic activity during fall through winter. Regardless of empty bed residence time (EBRT) (5.3 to 26 s), NH3 removal efficiency (RE) was about 90% with inlet concentrations of ≤1.1 mg m-3. With higher NH3 loading rates, the RE may differ from this study. In fall, CH4 RE was 49% (EBRT = 26 s) but only 13% in summer (EBRT = 13 s). Nitrous oxide RE varied in a narrow range of 14% to 18% over the study. In summer, CO2 removal was negligible but was 15% in fall and 34% in winter. While a compost based medium may be more effective for CH4 and N2O mitigation, a wood chip based medium would be more economical. Care should be taken when using a photoacoustic sensor for high-frequency and low-concentration NH3 measurements.}, number={3}, journal={Transactions of the ASABE}, publisher={American Society of Agricultural and Biological Engineers (ASABE)}, author={Hood, Matthew C. and Shah, Sanjay B. and Kolar, Praveen and Li, Lingjuan Wang and Stikeleather, Larry}, year={2015}, month={Jun}, pages={771–782} } @article{lingjuan_2015, title={Insights to the formation of secondary inorganic PM2.5: Current knowledge and future needs}, volume={8}, number={2}, journal={International Journal of Agricultural and Biological Engineering}, author={Lingjuan, W. L.}, year={2015}, pages={1–13} } @inproceedings{lingjuan_2013, title={Techniques for characterization of particulate matter emitted from animal feeding operations}, volume={1126}, booktitle={Evaluating veterinary pharmaceutical behavior in the environment}, author={Lingjuan, W. L.}, year={2013}, pages={15–39} } @article{wang-li_li_wang_bogan_ni_cortus_heber_2013, title={The national air emissions monitoring study's southeast layer site: Part I. Site characteristics and monitoring methodology}, volume={56}, number={3}, journal={Transactions of the ASABE}, author={Wang-Li, L. and Li, Q. F. and Wang, K. and Bogan, B. W. and Ni, J. Q. and Cortus, E. L. and Heber, A. J.}, year={2013}, pages={1157–1171} } @article{li_wang-li_wang_chai_cortus_kilic_bogan_ni_heber_2013, title={The national air emissions monitoring study's southeast layer site: Part II. Particulate matter}, volume={56}, number={3}, journal={Transactions of the ASABE}, author={Li, Q. F. and Wang-Li, L. and Wang, K. and Chai, L. and Cortus, E. L. and Kilic, I. and Bogan, B. W. and Ni, J. Q. and Heber, A. J.}, year={2013}, pages={1173–1184} } @article{wang-li_li_chai_cortus_wang_kilic_bogan_ni_heber_2013, title={The national air emissions monitoring study's southeast layer site: Part III. Ammonia concentrations and emissions}, volume={56}, number={3}, journal={Transactions of the ASABE}, author={Wang-Li, L. and Li, Q. F. and Chai, L. and Cortus, E. L. and Wang, K. and Kilic, I. and Bogan, B. W. and Ni, J. Q. and Heber, A. J.}, year={2013}, pages={1185–1197} } @article{li_wang-li_bogan_wang_chai_ni_heber_2013, title={The national air emissions monitoring study's southeast layer site: Part IV. Effects of farm management}, volume={56}, number={3}, journal={Transactions of the ASABE}, author={Li, Q. F. and Wang-Li, L. and Bogan, B. W. and Wang, K. and Chai, L. and Ni, J. Q. and Heber, A. J.}, year={2013}, pages={1199–1209} } @article{yao_shah_willits_westerman_li_marshall_2011, title={Ammonia emissions from broiler cake stockpiled in a naturally ventilated shed}, volume={54}, DOI={10.13031/2013.39830}, abstractNote={Due to concerns about the negative environmental impacts of ammonia (NH3), the EPA may soon regulate NH3 emissions from livestock operations, including waste piles. This would require knowledge of NH3 emission rates, but there are very few field-scale studies on emission measurement from broiler waste stockpiles. This is the first study in which short-term NH3 fluxes from broiler cake stockpiled in a shed were measured, taking into account both forced and natural convection. Acid scrubbers were used to measure NH3 concentrations, while the integrated horizontal flux (IHF) method and Fick's law of diffusion were used to determine NH3 emissions due to forced and natural convection, respectively. Average daily air temperature and wind speed 0.75 m above the stockpile were 24.9°C and 0.65 m s-1 in summer and 8.5°C and 1.02 m s-1 in winter. Natural convection accounted for <0.01% of total emission, but not isolating gas concentrations during forced convection conditions generally led to overestimation of emission. In summer (7 d), NH3-N emission factors were 17 g m-2 d-1 (stockpile surface area), 30 g m-3 d-1 (stockpile volume), 1.8 g kg-1 N d-1 (initial cake N content), and 11 g AU-1 d-1 (where AU = 500 kg live weight marketed). During the first 7 d of the winter study, the emission factors were 27 g m-2 d-1, 43 g m-3 d-1, 2.1 g kg-1 N d-1, and 18 g AU-1 d-1, respectively. For the 15 d study, the emission factors changed very little. Higher emissions in winter were due to higher wind speeds, broiler cake total Kjeldahl N (TKN), and pH. While air temperature also affected emissions, stockpile temperatures (not measured) due to microbial activity were probably more important. Care should be taken in extrapolating this study's results to other stockpiles due to differences in stockpile dimensions, chemical properties, and environmental conditions.}, number={5}, journal={Transactions of the ASABE}, author={Yao, H. and Shah, Sanjay and Willits, D. H. and Westerman, P. W. and Li, L. W. and Marshall, T. K.}, year={2011}, pages={1893–1904} }