Post on 22-Aug-2020
Ammonia volatilisation from livestock slurries and mineral fertilizers
Sven G. Sommer Technical Faculty, University of
Southern Denmark
Nitrogen, Phosphorus and Oxygen NPO-decade (Overgård 1982; Sommer 1982)
• NPO was the front runner of the Action Plan for the Aquatic
• Environment I to III (APAE-I-III, Vandmiljøhandlingsplaner).
Nanimal manure, kg N Ha-1
0 20 40 60 80 100 120
Nap
plie
d -
Nne
ed,
Kg
N H
a-1
0
10
20
30
40
50
60
Nitrat i brøndvand
År1930 1940 1950 1960 1970 1980 1990
3
2
4
6
8
10
12
14
Year
Nitrate in well water
Nitr
ate,
NO
3 pe
r ltr.
• Nitrate bomb • Blue babies
Ammonium in rainwater (Sommer, 1984 & 2013). Idea for this work was provided by Eivind Hansen, Head of
Centre for Terrestrial Ecology • Acidification and eutrophication
of natural ecosystems
• Airborne particulates that is a health hazard
• UN have included NH3 in the Convention on Long-range Transboundary Air Pollution (CLRTP)
• EU has set a limit – the NH3 ceiling – to the emission of NH3
Year
1920 1930 1940 1950 1960 1970 1980
Dep
ositi
on o
f N
, kg
N h
a-1
0
2
4
6
8
10
12AmmoniumNitrate
Example of EU regulations the Gothenborg protocol deals with ammonia
Reduced NH3 emission from 1990 to 2010, in pct. of emission in 1990
0 20 40 60 80
Reduction targets
Netherland
Belgium
Portugal
United Kingdom
Germany
Sweden
Austria
Reduced NH3 emission from 1990 to 2010, in pct. of emission in 1990
0 10 20 30 40 50 60 70
ReductionReduction target
Netherland
Belgium
Portugal
United Kingdom
Germany
Sweden
Austria
Ammonia emission - processes
From: • Stored slurry • Slurry applied in the field • Mineral fertilizer in the field
They have the release and emission processes in common
(Temp)/KO)(H1TAN(aq)(aq)NH
N33 ++
=(aq)][NH(aq)][NH[TAN] 34 += +
Understanding the system, slurry applied onto soil
Hours
0 48 96 144 192
Cum
ulat
ed N
H3-
emis
sion
, % o
f TA
N
0
5
10
15
20
Emis
sio
n r
ate,
kg
NH
3-N
h-1
0.0
0.5
1.0
1.5
2.0
2.5
Slurry applied onto soil (Sherlock, Sommer, Khan, Wood, Guertal, Freney, Dawson and Cameron, 2002; Sommer,
Olesen and Christensen, 1991)
Hours
0 48 96 144 192C
umul
ated
NH
3-em
issi
on, %
of T
AN
0
5
10
15
20
Emis
sio
n r
ate,
kg
NH
3-N
h-1
0.0
0.5
1.0
1.5
2.0
2.5
Hours from or applying slurry
0 50 100 150 200 250 300
Sur
face
pH
7.4
7.6
7.8
8.0
8.2
8.4
8.6
8.8 Sherlock et al. (2002)Sommer et al. (1991)
The pH buffer system of animal slurry and anaerobic digested slurry (Sommer and Husted, 1995)
HCO3−(aq) + H3O+(aq) ⇌ CO2 aq + 2H2O l
R − COOH(aq) + H2O(l) ⇋ RCOO−(aq) + H3O+(aq)
NH4+(aq) + H2O l ⇌ NH3 aq + H3O+(aq)
Pig slurry
pH
0 2 4 6 8 10 12 14
Buf
ferc
apac
ity,
(meq
L-1
) pH
-1
0
20
40
60
80
100
120
140 Measured Predicted
Electric charge of organic matter - particles (Sommer and Husted, 1995)
TAL: Total Alkalinity is the amount of equivalents of hydrons (H+(aq)) that has to be added to the biomass to reduce pH to 4.5.
Dry matter, g kg-1
0 20 40 60 80 100 120
Res
idua
l alk
alin
ity,
eq.
mol
L-1
0.00
0.05
0.10
0.15
0.20
The negative charged particles may explain the low emissions after 24-48 h – i.e. only 15-20% of the TAN is lost.
Hours
0 48 96 144 192
Cum
ulat
ed N
H3-
emis
sion
, % o
f TA
N
0
5
10
15
20
Emis
sio
n r
ate,
kg
NH
3-N
h-1
0.0
0.5
1.0
1.5
2.0
2.5
Organic matter (Dry matter) in slurry may also reduce infiltration of slurry liquid containing TAN
(Sommer and Olesen, 1991)
Dry matter content, g L-1
0 50 100 150 200 250
Emis
sion
, %
of
TAN
0
20
40
60
80
100
1206 hours6 days6 hours6 days
Dry matter (DM) is an indicator of reduced liquid infiltration
(Thygesen, Triolo and Sommer, 2012)
• High viscosity • Seal soil surface • Increase water
retention
Dry matter, %
0 2 4 6 8 10
Vis
cosi
ty,
cP
F(x)=1.82·e0.606·x
R2=0.83
1000
100
10
1
NH3 volatiliasation vs. infiltration (Sommer and Jacobsen, 1999)
Bromide infiltration
Bromide, mg Br- kg-1(dry soil)
0 50 100 150 2001000 2000
Dep
th,
cm
0.0
0.5
1.0
1.5
2.0
2.5
3.0
0.01 g(H2O) g-1(soil)
0.12 g(H2O) g-1(soil)
0.19 g(H2O) g-1(soil)
TAN (NH3+NH4+) infiltration
TAN, mg TAN- kg-1(dry soil)
0 200 400 600 800D
epth
, cm
0.0
0.5
1.0
1.5
2.0
2.5
3.0
0.01 g(H2O) g-1(soil)
0.12 g(H2O) g-1(soil)
0.19 g(H2O) g-1(soil)
NH3 volatilisation
Time from start of experiment, h0 12 24 36 48 60 72 84 96
NH3,
NH 3
% o
f TAN
0
10
20
30
40
0.01 g(H2O) g-1(soil)
0.12 g(H2O) g-1(soil)
0.19 g(H2O) g-1(soil)
Empirical emission model (Sherlock, Freney, Bacon and van der Weerden, 1995; Sommer, Søgaard, Møller and Morsing,
2001)
)NHNH( A3,G3, −××= uKF
• Wind (u) speed at 1 m above source
• K dependent on surface characteristic (Here bare soil)
• Air temperature • TAN and pH in source
surface
[ ] [ ][ ] N3
G3, /KOH1TAN(aq)1NH
++⋅=
H
u x [NH3(g)] mg(N) m-2 s-1
0 50 100 150 200 250 300 350Emis
sion
mea
sure
d, m
g(N
) m
-2 s
-1
0.000
0.005
0.010
0.015
0.020
0.025
0.030
0.035
Sherlock et al. 1995Sommer et al. 2001
Atmospheric transfer model (Olesen and Sommer, 1993)
FA =1
Ra + Rb + Rc∙ ( NH3,𝐺𝐺 − NH3,a )
Ra Turbulent air resistance
Rb Laminar air layer resistance
Rc Surface layer resistance
𝑅𝑅𝑎𝑎 x, t =ln( 𝑙𝑙z0
)
κ · u∗(t) z0: roughness length of the surface 𝑙𝑙: height of the internal boundary layer
𝑈𝑈∗: friction velocity 𝑅𝑅𝑏𝑏 = 6.2 ∙ u∗−0.67
Rc : measured resistance
Atmospheric emission model (Olesen and Sommer, 1993)
Ra=18 s m-1; at 8 m s-1 Ra=71 s m-1; at 2 m s-1
Rb= 9 s m-1; at 8 m s-1 Rb=22 s m-1; at 2 m s-1
Rc Manure store Uncovered: Rc= 18 s m-1; Surface crust: Rc=118 s m-1
Rc Fertilizer or manure in field Bare soil vs. high plants: Rc= 10 - 230 s m-1
Rc= 10 - 230 s m-1;
Micrometeorological transfer model slurry store (Sommer, Sibbesen, Nielsen, Schjørring and Olesen, 1996)
Data Initial bulk TAN and pH Hourly climate data, air
temperature and wind speed
Diffusion/convection transport of TAN in slurry
Rc set to =0 Assumed that effect of
distance from slurry surface to rim of the tank may improve model performance? Measured NH3 emission, g N m-2d-1
0 1 2 3 4 5
Estim
ated
NH
3 em
issi
on,
g N
m-2
d-1
0
1
2
3
4
5
1:1 line
Trail hose application of slurry (Thorman, Hansen, Misselbrook and Sommer, 2008)
Crop height (cm)0 20 40 60 80Em
issi
on re
lativ
e to
unc
ropp
ed, p
ct
0
20
40
60
80
100
120 F(x)=-1,1+91,4x, r2=0.73
Effect of increasing infiltration – harrowing the soil before slurry application
(Sommer and Ersbøll, 1994)
Hours from start of experiment
0 24 48 72 96 120 144
NH
3 em
issi
on,
% o
f TA
N
0
10
20
30
40
50 Harrowed soilUnworked soil
Direct injection of slurry applied in field (Hansen, Sommer and Madsen, 2003)
Volume of slot, m3 ha-1
0 10 20 30 40 50 60 70
Emis
sion
rela
tive
to tr
ail h
ose
appl
ied,
%
102030405060708090
Acidification of slurry (Kai, Pedersen, Jensen, Hansen and Sommer, 2008)
Nitrogen loss, % of total N
0 10 20 30 40 50
UntreatedAcidified
Winter 6 mth.
Whole year 12 mth.
Slurry storage Slurry applied in the field
Hours from slurry application
0 50 100 150
NH
3 em
issi
on,
% o
f am
mon
ium
0
10
20
30
40
50
60
AcidifiedUntreated
Factors affecting ammonia loss – The ALFAM model (Søgaard, Sommer, Hutchings, Huijsmans, Bussink and Nicholson, 2002)
Experimental factor Effect on NH3 volatilisation
Soil moisture Wet soil 10% higher than dry soil
Air temperature +2% per °C
Wind speed +4% per m/sec
Slurry type Pig slurry 14% less than cattle slurry
Dry matter content +11% per % DM
TAN content Positive
Manure incorp. No incorp. 11 times higher than shallow cult. and injection
Link: WWW.ALFAM.dk
The ALFAM model – Validation (Søgaard, Sommer, Hutchings, Huijsmans, Bussink and Nicholson,
2002)
Observed NH3 volatilization,pct.
0 10 20 30 40 50 60
Pred
icte
d N
H3 v
olat
iliza
tion,
pct.
0
10
20
30
40
50
60
Trail hoseInjectionr2=0.596
Conclusion
• Efficient techniques to reduce emission are developed and in use
• Models estimating ammonia emission from stored and applied manure should be developed accounting for the environmental condition, manure characteristics, management and treatment
• We need to improve our understanding “source” surface pH Perspective • Animal production is increasing and production systems
changes without adapting manure management. This lead to increased pollution – which has to be reduced by developing environmentally friendly manure management.