Abstract

The objective of this investigation was to determine the diurnal variation in the emission of NH3, CO2 and water vapour from an uninsulated deep litter building for fattening pigs and to investigate the influence of air temperature and airflow rate on the NH3 emission. The investigation was carried out in an uninsulated experimental building with 125 fattening pigs. The concentration of NH3 and CO2, the outside and inside air temperature, the outside and inside relative humidity and the animal activity were measured continuously during six days at a constant airflow rate of 146 m3/m2h. During six nights the effect of airflow rate on the NH3 emission was investigated by changing the airflow rate in steps from 26 m3/m2h to 165 m3/m2h. The emission of NH3, CO2 and water vapour from the uninsulated, deep litter building for growing/finishing pigs showed a clear diurnal variation. During the six days with constant airflow rate the NH3 emission varied from 6% to 247% of the mean, with the minimum around 6.00 a.m. and the maximum around 5.00 p.m.. The diurnal variation of NH3 emission was correlated to the inside air temperature (rs=0.86-0.91) and the animal activity (rs=0.69-0.83). The relative NH3 emission flux increased from 0.2 to 2.0 between the air temperatures -2 to 14oC inside the building. An increase in airflow rate through the building from 26 m3/m2h to 165 m3/m2h increased the relative NH3 emission flux from 0.4 to 1.4. The CO2 emission had a diurnal variation between 61% to 249% of the mean. The CO2 emission was correlated to the inside air temperature (rs=0.42-0.83) and animal activity (rs=0.67-0.85). The daily mean of water vapour emission varied between 18% to 269% of the mean. The water vapour emission was correlated to the inside air temperature (rs=0.53-0.97), animal activity (rs=0.57-0.85) and the water absorption capacity of the inlet air (rs=0.27-0.94)

Keywords

Ammonia; carbon dioxide; water vapour; emission; fattening pigs; deep litter

Published in

Publisher: Forskningscenter Bygholm, Horsens, Danmark

Conference

International Symposium on GASEOUS AND ODOUR EMISSIONS FROM ANIMAL FACILITIES

SLU Authors

• Jeppsson, Knut-Håkan

  • Department of Agricultural Biosystems and Technology, Swedish University of Agricultural Sciences
    

UKÄ Subject classification

Agricultural Science
Environmental Sciences related to Agriculture and Land-use


Permanent link to this page (URI)

https://res.slu.se/id/publ/2670