Air Emission and Energy Usage Impacts of No Pit Fans in a Wean to Finish Deep Pit Pig Facility

What Is Being Measured?

The objectives of this research project are to monitor the indoor air quality of a deep-pit; wean-to-finish pig building over one pig-growth cycle (six months) by semi-continuously measuring concentrations of ammonia (NH3), hydrogen sulfide (H2S), carbon dioxide (CO2), methane (CH4), and volatile organic compounds (VOCs) and intermittently measuring particulate matter (PM10) and odor. The project will also monitor semi-continuous emissions of NH3, H2S, CO2, CH4, and VOCs plus intermittent sampling of odor emissions from the barn’s pit and wall exhaust streams over the six month growth period. Energy usage, both electrical and LP gas usage will be measured for both pit and non-pit ventilated rooms over the pig growth, along with pig performance (daily gain, feed efficiency, and death loss) between the rooms.

Current Activities

A cooperating pork producer is being located in southern Minnesota with a tentative starting date of July 1, 2008 for data collection.

Does the Use of Pit Fans Make a Difference in Air Emissions from Deep-Pit Pig Barns?

Air emissions from tunnel ventilated pig finishing barns have been monitored and partitioned between pit and wall fans during the past two years in Minnesota. The results showed that a disproportionate amount of hydrogen sulfide (H2S) and ammonia (NH3) emissions were emitted from the deep pit finishing barn through pit fans even though it was concluded that “pit” ventilation has little effect on the barn’s indoor air quality (figure 1). Thus producers might be able to reduce emissions of these hazardous gases and the associated odor of these gases simply by limiting or not using pit ventilation fans. Such a strategy would save electrical energy use since larger more efficient wall fans could replace the less efficient pit fans.

Figure 1. Hydrogen Sulfide Emissions from a 1200 head pig finishing barn with varying pit ventilation rates during a winter (January 26 to March 4, 2006) period. Contributed to eXtension CC2.5

Why is This Important?

Data collected from the deep pit facility will be used to determine the benefit of pit fans to indoor air quality in swine wean to finish buildings and what impact the use of pit fans has on energy usage and gas, odor, and particulate matter emissions from this stage of pork production buildings .

For More Information

Jacobson, L.D., B.P. Hetchler, and D.R. Schmidt. 2007. Sampling pit and wall emission for H2S, NH3, CO2, PM, & odor from deep-pit pig finishing facilities. Presented at the International Symposium on Air Quality and Waste Management for Agriculture. Sept 15-19, 2007. Broomfield, CO. St. Joseph, Mich.: ASABE

Authors: Larry D. Jacobson, David Schmidt and Brian Hetchler, University of Minnesota

This report was prepared for the 2008 annual meeting of the regional research committee, S-1032 “Animal Manure and Waste Utilization, Treatment and Nuisance Avoidance for a Sustainable Agriculture”. This report is not peer-reviewed and the author has sole responsibility for the content.

Odor Emissions and Chemical Analysis of Odorous Compounds from Animal Buildings

Why Study Odor Emissions from Animal Housing?

  • To determine odor emission characteristics by using common protocols and standardized olfactometry, from four mechanically-ventilated National Air Emissions Monitoring Study (NAEMS) sites, two dairy and two swine.
  • To develop a comprehensive chemical library that delineates the most significant odorants, and correlate this library with olfactometry results.
  • To disseminate information to stakeholders including producers, agencies, regulators, researchers, local government officials, consultants, and neighbors of animal operations.

Current Activities

Data is being collected from the four NAEMS sites (dairy sites in Wisconsin and Indiana and pig sites in Iowa and Indiana). Data collection is about ¼ completed (first 13 week cycle completed in April, 2008 and second cycle started in May, 2008) Raw data compilation in a U of MN website based spreadsheets for this first round is nearly completed. Olfactometry data is being done at the U of MN, Iowa State, and Purdue labs while GC-MS data is analyzed at West Texas State University and GC-MS-O data is processed at Iowa State University.

What We Have Learned

Sorbent tubes for both GC-MS data and GC-MS-O data have been successfully used to trap VOC in the emissions streams from the four barns without “breakouts” occurring. Approximately 15 to 20 compounds are being identified and with airflow data, actual emission data of these compounds should be able to be calculated.

instrumentation trailer making air quality measurements and air flow rates as part of the NAEMS study

Why is This Important?

This study is supplementing the National Air Emissions Monitoring Study (NAEMS) with comprehensive measurements of odor emissions. The NAEMS will help livestock and poultry producers comply with EPA regulations concerning regulated gases and particulate matter by monitoring these pollutants continuously for 24 months, in order to determine which types of farms are likely to emit threshold levels of contaminants under the current regulations. Although odor plagues the animal industry with the greatest overall challenge, it is not included in the NAEMS, because the EPA does not regulate it and therefore did not include it in the Air Consent Agreement.

This project adds odor emission measurements at four NAEMS sites during 12 months of the study. Both standard human sensory measurements (using dynamic forced-choice olfactometry), and a novel chemical analysis technique (GC-MS-O) for odorous compounds found in these emissions is being done in this study. The sensory and chemical methods would be correlated to gain both quantitative and qualitative understanding of odor emissions from animal buildings.

For More Information

Contact Larry D Jacobson, University of Minnesota, BBE Department, 1390 Eckles Ave, St. Paul, MN 55108. email: or phone 612-625-8288.

Larry D. Jacobson, Ipek Celen and Brian Hetchler, University of Minnesota

This report was prepared for the 2008 annual meeting of the regional research committee, S-1032 “Animal Manure and Waste Utilization, Treatment and Nuisance Avoidance for a Sustainable Agriculture”. This report is not peer-reviewed and the author has sole responsibility for the content.

Clearing the Air on Biofilters

Biofilters have been widely adopted to filter gas, odor and particulate matter from livestock facilities. However, the science behind “how they work” and the configurations that are in practice are continually evolving. This webinar discusses past and present applications of biofilters, on-going research to better design and manage biofilters, and how to incorporate biofilters as part of an environment control system.This webcast was originally broadcast on December 7, 2012. More… Continue reading “Clearing the Air on Biofilters”