Reprinted, with permission, from the proceedings of: Mitigating Air Emissions From Animal Feeding Operations Conference.
Recent dairy emission research has identified alcohols (methanol and ethanol) as the major volatile organic compound (VOC) group originating from fresh waste (Shaw et al., 2007; Sun et al., 2008). Effective control of these alcohols from dairies will help the dairy industry meet regulatory standards, satisfy public concerns, and improve local and regional air quality. Enhancing industry typical freestall waste management practices, which currently are predominant practices like flushing and scraping of fresh waste, may provide a large impact on mitigation of oxygenated VOC emissions in a cost effective manner.
Our research has shown that flushing is more effective than scraping in reducing methanol (MeOH) and ethanol (EtOH) emissions from barns. Flushing three times daily versus scraping three times daily yields an emission reduction efficiency of 50% for both MeOH and EtOH. Furthermore, flushing frequency by itself significantly reduces emissions. A comparison of 3 times versus 6 times flushing daily showed decreased emissions by 79% for MeOH and 63% for EtOH.
There is no cost associated with increasing the flushing frequency of a liquid manure handling system. Essentially, flushing frequency is increased, while the amount of water per flushing event is decreased. Since the water used to flush barns is recycled water from the lagoons, there is no cost to re-circulate lagoon water through the barn alleys.
M. Calvo, K. Stackhouse, Y. Zhao, Y. Pan, Ts Armitage, and F. Mitloehner, University of California, Davis
Point of Contact:
Frank Mitloehner, firstname.lastname@example.org
The information provided here was developed for the conference Mitigating Air Emissions From Animal Feeding Operations Conference held in May 2008. To obtain updates, readers are encouraged to contact the author.