A dual tracer ratio method for comparative emission measurements in an experimental dairy housing. (April 2018)

• Record Type: Journal Article
• Authors: Mohn, Joachim; Zeyer, Kerstin; Keck, Margret; Keller, Markus; Zähner, Michael; Poteko, Jernej; Emmenegger, Lukas; Schrade, Sabine
• Is Part Of: Atmospheric environment. Volume 179(2018)
• Page Start: 12
• Page End: 22
• Publication Date: 2018-04
• Subjects: Experimental dairy housing -- Tracer ratio method -- Comparative emission measurement -- Ammonia -- Greenhouse gas; Air -- Pollution -- Periodicals; Air -- Pollution -- Meteorological aspects -- Periodicals; 551.51
• DOI: 10.1016/j.atmosenv.2018.01.057
• Languages: English
• ISSNs: 1352-2310

Abstract

Abstract: Agriculture, and in particular dairy farming, is an important source of ammonia (NH3 ) and non-carbon dioxide greenhouse gas (GHG) emissions. This calls for the development and quantification of effective mitigation strategies. Our study presents the implementation of a dual tracer ratio method in a novel experimental dairy housing with two identical, but spatially separated housing areas. Modular design and flexible floor elements allow the assessment of structural, process engineering and organisational abatement measures at practical scale. Thereby, the emission reduction potential of specific abatement measures can be quantified in relation to a reference system. Emissions in the naturally ventilated housing are determined by continuous dosing of two artificial tracers (sulphur hexafluoride SF6, trifluoromethylsulphur pentafluoride SF5 CF3 ) and their real-time detection in the ppt range with an optimized GC-ECD method. The two tracers are dosed into different experimental sections, which enables the independent assessment of both housing areas. Mass flow emissions of NH3 and GHGs are quantified by areal dosing of tracer gases and multipoint sampling as well as real-time analysis of both tracer and target gases. Validation experiments demonstrate that the technique is suitable for both areal and point emission sources and achieves an uncertainty of less than 10% for the mass emissions of NH3, methane (CH4 ) and carbon dioxide (CO2 ), which is superior to other currently available methods. Comparative emission measurements in this experimental dairy housing will provide reliable, currently unavailable information on emissions for Swiss dairy farming and demonstrate the reduction potential of mitigation measures for NH3, GHGs and potentially other pollutants. Graphical abstract: Image 1 Highlights: Dairy housing constructed for comparable emission reduction measurements. Tracer ratio method used to quantify emissions of naturally ventilated housing. Areal dosing, multipoint sampling and real-time analysis of tracer and target gases. Successful validation of tracer method for point and areal emission sources. Cross-contamination between areas negligible, but background correction required.