298 94 307/02 Untersuchungen zum Stand der Umsetzung des ...

Teil 3 Seite 7-1
7 CURRENT CONSUMPTION AND EMISSION LEVELS IN IN-
STALLATIONS FOR THE DISPOSAL OR RECYCLING OF
ANIMAL CARCASES AND ANIMAL WASTE
7.1 Animal by-products
Within the project to determine the typical current emissions, analyses were run at a se-
lected carcass disposal plant. The plant in question processes carcasses and slaughter
residues, feathers, blood, and by-products from poultry slaughtering in separate treatment
lines.
The sterilisation of the material is done in this plant discontinuously in a batch cooker at
133°C at 3 bar pressure for 20 minutes.
The next step in the process is the drying of the wet slurry in a continuous disk dryer. In
the dryer, the temperature increases from 100°C to about 130°C with the evaporation of
water from the sterilised material.
One special feature of this plant is the ammonia conversion unit, where the volatile am-
monia is removed from the exhaust vapours from the evaporation. After having been freed
from the ammonia, the exhaust vapours are then condensed into acetic vapours. By add-
ing urea, it is possible to produce a solution of ammonium nitrate and urea of 28% (AHL
28).
The following diagram shows the substance balance of the analysed plant, staged ac-
cording to raw material amount, substances used, emissions, and products.