Effect of partial pit exhaust ventilation system on ammonia removal ratio and mass transfer coefficients from different emission sources in pig houses

Li Rong
2020 Energy and Built Environment  
Please cite this article as: Li Rong , Effect of partial pit exhaust ventilation system on ammonia removal ratio and mass transfer coefficients from different emission sources in pig houses, Energy and Built Environment (2020), doi: https://doi. Highlights:  Effects of partial pit exhaust locations on ammonia removal ratio  Effects of partial pit exhaust locations on ammonia mass transfer coefficients  Effects of partial pit exhaust ventilation on ammonia removal ratio  Optimal design of
more » ... ptimal design of slatted floor is necessary to abate the emissions Effect of partial pit exhaust ventilation system on ammonia removal ratio and mass transfer coefficients from different emission sources in pig houses Abstract A partial pit exhaust ventilation (PPEV) system installed below the slatted floor has been widely used in fattening pig barns nowadays in Denmark. Experimental tests showed that annually around 50% of ammonia emissions was collected by PPEV system. However, the percent of emissions collected by PPEV system from different emission sources including slurry manure surfaces, top surfaces, bottom surfaces and side surfaces of the slatted floor has not been investigated as well as the mass transfer coefficients. This study applied CFD modeling to investigate the removal ratio of ammonia emissions from four emission surfaces including the top, side, bottom surfaces of the slatted floor and slurry manure surfaces. The CFD model was validated by experimental air speeds measured in a room equipped with two full-scale pigpens. The validated CFD model was further adopted to simulate cases under five ventilation rates (2000-4000 m 3 /h), four emission sources and two locations of PPEV system exhaust. The results showed that the removal ratios of ammonia emissions by PPEV system from the four emission sources were generally higher for the cases that the PPEV exhaust was installed opposite to the air supplier than the values of those cases that the PPEV exhaust was located at the same side of side wall air supplier. The removal ratios of ammonia emissions were the highest with the emission source of slurry manure surface and generally 30% higher than the values of other cases. The mass transfer coefficients with the emission sources on 3 the side surfaces of the slatted floor were the largest. The results indicated that the airflow patterns and locations of emission sources greatly influenced the removal ratios of ammonia emissions and ammonia mass transfer coefficients.
doi:10.1016/j.enbenv.2020.04.006 fatcat:ur4yvruk7zfrthq5fv5576psr4