The Influence of the Mode of Pigs Raising on the Level of Ammonia
Emission from Buildings
Andrzej Myczko
Research objectives
The main aim of the study was to determine the effect of the most important physical factors
on the level of ammonia emission from piggery in fattening house, and the relation between
the most widely applied modes of raising the animals and the level of ammonia emission.
Particular aims, which were also adopted as operational tasks, included:
1. Determination of the interdependence of the level of ammonia emission in the air
removed from buildings for livestock and the basic microclimate parameters (air
temperature and air relative humidity) as well as the season of the year and time of
measurement - for the most frequently applied modes of pigs raising.
2. Development of a posteriori mathematical models describing concentration of ammonia
emission from buildings for livestock with reference to the modes of pigs raising in
Poland.
3. Optimization computation of the concentration of ammonia emission for the tested modes
of pigs raising.
4. Determination of a total ammonia emission, originating from raising pigs in the whole
country (taking into account diverse modes of breeding, emission from buildings for
livestock and emissions outside the buildings - during animal excrements deposition and
utilization.
Research problem, scope of the project, subject of the project
Research problem
With reference to the aims of the project already presented and literature of the subject, the
following questions were formulated and accepted as research problems:
1. What absolute values does ammonia emission reach in buildings for livestock for the most
widely used modes of pigs breeding?
2. Are the quantitative differences of ammonia emission from buildings for livestock
statistically significant (for the most widely used modes of pigs raising)?
3. In the most widely used modes of pigs raising, is the interactive effect of the following
factors on the level of ammonia emission from the buildings for livestock significant?
- air temperature and air relative humidity in the building,
- season of the year,
- measurement time schedule in the day cycle.
2
An empirical way is the only route to obtain information to answer the above questions;
hence, it was necessary to design and subsequently carry out experiments. By solving the
problems it will be possible to indicate paradigms how to implement particular solutions in
the buildings for livestock, which may be considered environment-friendly.
On the basis of literature studies and the results of experiments performed by the author
[Myczko 1997, 1998] the following research assumptions were accepted: division of the pen
area into the following zones: den, feeding, manure, according to the functional and technical
paradigms encouraging animals to lay their excrements mainly in the manure zone, will lead
to reduction of ammonia emission from the fattening house. This will be achieved mainly by
confining the area of moistened floors, from which large amounts of ammonia are emitted.
This assumption was subject to experimental validation in a fattening house no. 6.
Scope of the project
The studies were to be performed in appropriately constructed and exploited fattening houses,
each containing from 110 to 360 porkers. In these fattening houses the following modes of
raising pigs were adopted:
- on concrete floors, covered with a small amount of straw (etc. 0.15 - 0.25 kg of bedding
per porker a day),
- in pens, whose area in 25% is covered by slatted floor type,
- on deep litter,
- on deep litter specially treated with a manure decomposition agent (BIOSAN),
- on self-cleaning floors, inclined at a large degree (10%).
Subject of the project
Studies were conducted in six fattening houses: in five of them the most frequent systems of
breeding animals are used and in one - the system developed by the author. The selected
buildings are thermally stable, ensure appropriate temperature and air humidity in compliance
with the zootechnical standards. Diagrams of the fattening houses are presented in Fig. 1.
The basic criteria adopted when selecting the buildings were the following:
- appropriate application of the mode of pigs raising,
- representative character of the applied technological breeding system for fattening houses
in Poland,
- natural (gravitational) system of building ventilation.
Results and discussion
The measurements yielded concentration of ammonia, the temperature and relative humidity
of air in the studied houses and in air removed from those houses. The months in which the
tested parameters were recorded represent all seasons of the year and hence they can be said
to illustrate all characteristic changes of climate in our climatic zone.
3
Fig.1. Diagrams of the studied fattening houses
It was observed that the increase or decrease of ammonia concentration was always related to
the activity of the animals; their feeding or resting time, and to the presence of people taking
care of them. Increase in animals’ activity results in increase of ammonia concentration. It is
particularly well illustrated in bedded systems, where movement of animals on the bedding
augments evaporation and hence intensifies emission of ammonia and other gases.
On the basis of the analysis of variance conducted for all results, it was concluded that the
observed value of emitted ammonia is affected by all the three independent variables, i.e.:
- mode of pigs raising,
- season of the year in which measurements were taken,
- time of the measurement.
Fig. 2 illustrates the influence of particular technologies of animals raising on the mean values
of the emitted ammonia in an hour per one porker. Analyzing data from the Figure we can
observe that the highest amounts of ammonia (above 500 mg/h)) are emitted by porkers raised
according to mode no. 1. It has to be noted here that this mode, the most disadvantageous as
regards the amount of emitted ammonia, is the most widely used mode is Polish fattening
houses. The level of ammonia emitted for technologies no. 2 and 3, i.e. when animals are kept
in the grated system and on typically thick beddings, can be considered as standard level of
ammonia emission. The lowest levels of emission, close in values, were recorded for
technologies no. 4, 5, and 6, i.e. in technologies where the processes of excrements
decomposition are aided with special biological preparations (Fattening house no. 4) and in
technologies, in which the functional and constructional solutions are such that they reduce
4
Mean amounts of ammonia emitted
by one porker in one hour NH 3 [mg/h]
600
500
400
300
200
100
0
Mode - 1
Mode - 2
Mean amounts
Mode - 3
NH3 [mg/h]
Mode - 4
Mode - 5
Mode - 6
Confidence interval 95%
Fig. 2. Mean values and 95% Tukey’s confidence interval for the amount of emitted ammonia
per one porker at one hour for particular technologies.
the area where moist excrements and moist bedding are deposited (fattening houses no. 5
and 6).
Mean amounts ammonia emitted
by one porker in one hour NH 3
[mg/h]
400
350
300
250
200
150
100
50
0
4.00
8.00
Mean amounts
12.00
16.00
20.00
Time of measurement
NH3 [mg/h]
24.00
Confidence interval 95%
Fig. 3. Mean values and 95% Tukey’s confidence interval for the amount of emitted ammonia
expressed for one porker at one hour at particular times of measurement.
5
Mean values of emitted ammonia for one
porker at one hour NH3 [mg/h]
Fig. 3 presents a mean day distribution of the emitted ammonia and 95% Tukey’s confidence
interval for one porker. The greatest similarity between the values is observed between 4 a.m.
and 12 p.m. (24:00), i.e. when in all technologies of pigs raising, porkers are resting, and the
piggeries are still and quiet. Some similarity can also be noted between 12 a.m. and 8 p.m.,
i.e. at the time of the day when porkers are especially active, being fed, watered, or prepared
for the night rest. At these hours also heavy excrements discharge has been recorded. The
highest values of emitted ammonia have been monitored at 4 p.m.
350
300
250
200
150
100
50
0
Spring
Summer
Autumn
Season of the year
Mean amounts NH3 [mg/h]
Winter
Confidence interval 95%
Fig. 4. Mean values and 95% Tukey’s confidence interval for the amount of emitted ammonia
expressed for one porker at one hour for particular seasons of the year.
Fig. 4 shows mean values and 95% Tukey’s confidence interval for the amount of emitted
ammonia for one porker in the function of seasons of the year. Comparing the confidence
intervals we can observe the greatest uniformity between their values in spring and winter,
when the fattening houses have good microclimatic conditions. Besides, in the winter season,
probably due to effective thermal isolation of the buildings, the values show close similarity
also for the autumn and spring season. For these seasons of the year the mean values of
ammonia emitted in terms of one porker a day range 235-265 mg. In contrast, a great
difference is observed in summer, when probably due to higher temperatures outside the
fattening houses as well as higher temperature of the air flowing into the building, the level of
emitted ammonia increases above 265 mg/h.
6
Table 4. Ammonia production in the examined fattening houses
Parameter
Unit
1
Population
Exchange of air indoors
Ammonia content in
ventilated air
head
m3/day
ppm
mg/m3
Ammonia production in kg/day
ventilated air
kg/year
Ammonia production per kg/year
one production stand for
325 day exploitation of
fattening stands
2
110
147
34733 34111
55.50 43.90
39.10 30.60
1.358 1.047
441.35 340.27
4.01
2.31
Number of piggery
3
4
360
82512
36.40
25.30
2.063
670.47
1.86
5
6
358
131
96
86962 39658 20243
22.90 19.00 24.18
16.00 13.39 17.41
1.389 0.531 0.352
451.42 172.57 114.40
1.26
1.32
1.19
CONCLUSIONS
1. The total value of ammonia emission for the most frequently applied modes of pigs
raising in Poland - expressed in kg of ammonia emitted from one production stand in one
year is:
a) 4.01 - for mode no. 1 (concrete floors covered with a small amount of straw - 0.15 0.25 kg of bedding per one animals a day
b) 2.31 - for mode 2 (pens whose 25% area is covered with slatted floor)
c) 1.86 - for mode no. 3 (thick bedding)
d) 1.26 - for mode no. 4 (thick bedding treated with an agent improving manure
decomposition - Biosan)
e) 1.32 - for mode no. 5 (self-cleaning floor inclined at 10% degree
f) 1.19 - for mode no. 6 - (pen divided into den, feeding, and manure zones).
2. The total emission of ammonia from pigs fattening houses on the scale of the whole
country was estimated as 12.3 kt, while the value of emission including also the value for
ammonia emitted into the environment during animals excrement deposition and
utilization, was equal to 20.4 kt.
3. Results collected during the experiments and the derived mathematical models may be
useful in designing new fattening houses and in modernization of the already operating
ones.
4. Optimization procedure was used to determine such a combination of decisive variables,
which would ensure maximum reduction of ammonia emission from buildings for
livestock and so that it may range 4-8 g/day/1 animal.
5. The new design of porker pen (divided into den, feeding, and manure zones), verified
experimentally through mode no. 6 of pigs raising, may be considered environmentally
friendly. By using this mode it is possible to keep ammonia emission at the level 1.19 kg
per one breeding stand in one year. This solution is based on a mode permitting
organizational, functional and technical modernization of most buildings for livestock
where pigs are raised according to mode no. 1 (fattening house no. 1).
7
Literature
Aarnink A. J. A., Swiestra D. 1995. “The influence of slatted floor type on ammonia
emission”. Pigs-mistet., No. 7, vol. . 11: 35-37.
Gronauer A. et al., “Anforderungerund Lösungsansätze zur Bestimmung von Emissionstraten
ökosystem - und klimarelevanter Gase aus der Landbewirtschaftung.” Beiträge zur 2
Internationalen Tagung “Bau und Technik.” Potsdam, p. 147-156.
Hartung E., Keck M., Büscher W. 1994. “Luftqualität und Energieverbrauch bei Ober - ind
Unterflurabsaugung.” DGS, No. 9, pp. 13-16.
Hoy St., “Multigasmonitoring - Ergebnise aus der Schweine und Höchnchenmast.”
Landtechnik. No. 50, pp.270-271.
Myczko A., 1997. “Porównanie emisji amoniaku w tuczarniach o różnych rozwiązaniach
konstrukcyjnych kojców.” Materiały z VII Sympozjum im. Prof. Cz. Kanofojskiego. Vol. II,
Płock, pp. 82-87.
Romaniuk W. et al. 1995. Gospodarka gnojowicą i obornikiem. Warsaw: Wyd. Narodowy
Fundusz Ochrony Środowiska, p. 12-19.
8
The author:
Doc. Dr hab. Eng. Andrzej Myczko
Institute for Building, Mechanization and Electrification in Agriculture
in Warsaw
Branch Poznań,
ul. Biskupińska 67
60-463 Poznań
Poland
Phone: +48 61 820 33 31
Fax: +48 61 820 83 81
e-mail: ibmer@man.poznan.pl
http://www.ibmer.poznan.pl