Abatement of ammonia emissions from dairy cow house concrete floor surfaces through additive application.

Winter housing of dairy cows and beef cattle is common practise in north-western European countries such as the UK and Ireland. In cattle housing, urine and dung are deposited over a large floor surface area from which ammonia (NH 3) emissions may rapidly occur. The application of additives to this emitting layer has the potential to significantly reduce NH 3 volatilisation from cattle housing surfaces. A dynamic flow-through chamber based study was carried out to determine the NH 3 abatement potential of 10 additives applied to dairy cow slurry covered concrete surfaces under simulated northwest European winter housing conditions. Peak NH 3 fluxes for control (slurry only) treatments occurred at approximately 3–5 h post slurry application, peaking at 133 mg [NH 3 –N] m−2 h−1. Acidifiers offered the most potential for cost-effectively abating NH 3 emissions from slurry-fouled surfaces by increasing the NH 4 +:NH 3 ratio. Experimental data suggests that targeting a slurry pH of 6 at the housing floor stage can significantly reduce NH 3 emissions from fresh excreta. Of the tested additives, alum was the most successful at abating NH 3 emissions from slurry; particularly after 6 h (76% NH 3 abatement), where the efficacy of alum was greatest relative to the other acidifiers. Alum was followed by calcium chloride (69%) and sulphuric acid (41%). Actisan, a commercially available bedding disinfectant was another successful NH 3 abatement option (59% after 6 h). Caution is needed in extrapolating results from this chamber-scale study to cow house scale as spatial and temporal variability of excreta deposition and climatic factors create additional complexity. • Additives applied to slurry-fouled cattle floors significantly reduce NH 3 emissions. • 2 mm fresh dairy cow slurry layer at 12 °C simulating NW European housing conditions. • Peak NH 3 fluxes occurred at 3–5 h after excreta deposition, peaking at 133 mg [NH 3 –N] m−2 h−1. • Alum, calcium chloride and sulphuric acid reduced NH 3 emissions by 76, 69 and 41%. • Acidifiers have most potential for abating NH 3 emissions from cattle house surfaces. [ABSTRACT FROM AUTHOR]