Nitrous oxide supersaturation at the liquid/air interface of animal waste.
Concentrated animal feeding operations around the globe generate large amounts of nitrous oxide (N(2)O) in the surrounding atmosphere. Liquid animal waste systems have received little attention with respect to N(2)O emissions. We hypothesized that the solution chemistry of animal waste aqueous suspensions would promote conditions that lead to N(2)O supersaturation at the liquid/air interface. The concentration of dissolved N(2)O in poultry litter (PL) aqueous suspensions at 25 degrees C was 0.36 microg N(2)O mL(-1), at least an order of magnitude greater than that measured in water in equilibrium with ambient air, suggesting N(2)O supersaturation. There was a nonlinear increase in the N(2)O Henry constants of PL from 2810 atm/mole fraction at 35 degrees C to 17 300 atm/mole fraction at 41 degrees C. The extremely high N(2)O Henry constants were partially ascribed to N(2)O complexation with aromatic moieties. Complexed N(2)O structures were unstable at temperatures > 35 degrees C, supplying the headspace with additional free N(2)O concentrations.
Makris
Konstantinos C
KC
Cyprus International Institute for the Environment and Public Health in association with the Harvard School of Public Health, 5 Iroon Street, Nicosia 1105, Cyprus. kcmakris@gmail.com
Andra
Syam S
SS
Hardy
Michael
M
Sarkar
Dibyendu
D
Datta
Rupali
R
Bach
Stephan B H
SB
Mullens
Conor P
CP
D000393:Air Pollutants / Q000737:chemistry*; D000818:Animals; D005243:Feces / Q000737:chemistry*; D009609:Nitrous Oxide / Q000737:chemistry*; D011200:Poultry; D014874:Water Pollutants, Chemical / Q000737:chemistry*
D000393:Air Pollutants; D014874:Water Pollutants, Chemical; D009609:Nitrous Oxide