The main objective in this paper is to describe the
development of a procedure for a reliable determination
of yearly ammonia emission of pig houses starting with
as few field measuring days as possible. The method
takes into account that many variables influence NH3
emission and the hypothesis was that the relationship of
these with NH3 emission could be used for the
determination of yearly ammonia emission. An additional
investigation is also carried out to determine
whether the use of selection criteria for the measuring
days results in a better accuracy.
3. Material and methods
3.1. Pig housing
The experiments were conducted in two compartments
of a commercial fattening pig house in Bierbeek
(Belgium) equipped with a mechanical ventilation
system. Each compartment has a capacity for 156
fattening pigs and was divided into 12 pens. The farm
had a capacity for 580 fattening pigs.
Figure 1 shows a cross-section of a compartment. The
floor is divided into three parts: a wide slatted floor
(surface area 40% of pen) with manure pit below, a
domed solid floor (surface area 40% of pen) and a
narrow slatted floor (surface area 20% of pen). Under
the wide concrete slatted floors, a manure pit of 07 m
depth was built for collecting the faeces. Urine is
collected in a ditch under the narrow slatted floor. A
drainage system connects the manure pits from individual
pens to central manure pit. The pigs were fed with
dry feed. Air tubes provide the supply of fresh air
through a channel under the domed floor, bringing the
fresh air from both sides in a channel below the central
working corridor and finally through the slatted floor in
the corridor into the compartment. The air is extracted
via a central exhaust tunnel on top of the building
running along the length of the pig house. Two exhaust
openings connect to the tunnel from each compartment.
Indoor temperature was regulated with a temperature
controller, type Fancom FSU8 that controls the exhaust
openings with a measuring and throttling unit, type
Fancom FMS