1) The study assessed using sugar and cheese whey as alternatives to sulfuric acid for slurry acidification to minimize ammonia emissions during storage. 2) A laboratory experiment was conducted using 5L reactors containing raw cattle slurry or slurry treated with sulfuric acid, sugar, cheese whey, or rice bran over 2 months. 3) The results showed that all treatments reduced ammonia emissions compared to the raw slurry. Cheese whey was the most effective additive, reducing nitrogen losses by over 50% compared to over 80% for the raw slurry. Sugar also significantly reduced emissions. Rice bran had a smaller effect.

1. Alternative additives for slurry treatment during
storage to minimize ammonia emissions
VII Remedia
Workshop
Joana Prado1*
, Isabel Sousa1
, Maria Otília de Almeida Carvalho1
, Anabela Raymundo1
, David Fangueiro1
1
LEAF, Instituto Superior de Agronomia, Universidade de Lisboa, Tapada da Ajuda, 1349-017 Lisboa, Portugal
*
Contact author: joanavianaprado@gmail.com
The aim of the present work was
to assess the effect of slurry aci-
dification using new additives
(sugar and cheese whey) as alter-
native to sulfuric acid as well as
the potential of rice bran as crust
enhancer on ammonia emissions
mitigation during storage .
❶ Purpose ❷ Methods
❸ Results
Ammonia emissions were followed continuously
with acid traps using a device similar to the one
proposed by Hassouna et al. (2017).
Figure 1: Schematic representation of the model used to measure ammo-
nia emissions. (1. The reactor; 2. Orthophosphoric acid; 3. Water; 4. Si-
lica; 5. Gas Meter; 6. Flowmeter; 7. Pump)
NH3-Ncumul.
mg kg efl.
-1
Nt initial
g kg-1
Nt lost
%
NH4
+
initial
g kg-1
NH4
+
lost
%
NTS 1863.38a
2.02 46.12a
1.16 80.32a
ASS 7.34d
2.02 0.18e
1.16 0.32e
SS 1055.51c
2.02 26.13c
1.16 45.49c
WS 890.15c
2.02 14.69d
1.16 25.58d
RS 1523.42b
2.02 37.71b
1.16 65.70b
A laboratory experiment was performed with
small scale (5 L) reactors for 2 months. The
treatments (3 replicates) considered were:
❹ Conclusions
All treatments led to a reduction of the NH3 emis-
sions compare to the NTS.
From the method tested the use of cheese whey is
the most efficient additive in mitigating the NH3
emissions. The sugar is also a solution to adopt since
it led to half the emissions of the NTS.
The rice bran led to a small reduction and is not the
most effective solution.
References:
Hassouna, M., Eglin, T., Cellier, P., Colomb, V., Cohan, J., Decuq, C., Delabuis, M., Edouard, N., Espagnol, S., Eugène, J., 2017. Measuring emissions from livestock farming : greenhouse gases , ammonia and nitrogen oxides To cite this version :
HAL Id : hal-01567208. Petersen, S.O., Andersen, A.J., Eriksen, J., 2012. Effects of Cattle Slurry Acidification on Ammonia and Methane Evolution during Storage. J. Environ. Qual. 41, 88. | Piveteau, S., Picard, S., Dabert, P., Daumer, M.L., 2017.
Dissolution of particulate phosphorus in pig slurry through biological acidification: A critical step for maximum phosphorus recovery as struvite. Water Res.| Regueiro, I., Coutinho, J., Fangueiro, D., 2016a. Alternatives to sulfuric acid for slurry
acidification: Impact on slurry composition and ammonia emissions during storage. J. Clean. Prod. 131, 296–307.
• Raw cattle slurry (NTS)
• Slurry acidified with sulphuric acid (ASS)
• Slurry acidified with sugar (40 g kg-1
) (SS)
• Slurry acidified with cheese whey (500 g kg-1
)
(WS)
• Rice bran added (100 g kg-1
) on the slurry
surface (RS).
Till day 2 NH3 emissions were observed
only in NTS and SS and between day 2
and 15, only NTS emitted NH3. After
day 15, RS treatment started to emit
NH3 with values higher than NTS.
All methods applied and NTS started to
emit at higher rates on the second
month (except the ASS that kept a lo-
wer rate). From day 43 till the end of
the experiment, daily emissions rates
were similar in all treatments except in
ASS where a stable and significantly lo-
wer rate was observed.
Figure 2: The emissions rates of ammonia along stora-
ge period. Values are arithmetic means (n=3) and the bars
represent the standard error.
Table 1: The cumulative NH3-N for each modality and N losses compare to the initial total nitrogen (NT nitial), the
NH4
+
present in the initial slurry (NH4
+
initial). Values are arithmetic means (n=3). For each parameter, means followed by
different letters are significantly (P < 0.05) different from each other, based on a Tukey test in each column.
The highest cumulative NH3 emissions were observed in NTS. The alternative to ASS that
resulted in lower NH3 emissions was the WS, reducing losses of Nt from 46% to 15% and
NH4
+
from 80% to 26%.
The alternative solution with the lower efficiency was RS.
Acknowledgment
Funded by the Horizon 2020 Framework Programme
of the European Unionhttp://cost-livage.eu/