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Teil 3 Seite 2-4
To some degree, the hide removal is also done in a combination of mechanical and man-
ual work.
2.1.1.5 Head and hoof removal for cattle and sheep
After hide removal, the head is cut off from the body and transported to the head clean-
ing place without touching the floor or any of the implements.
2.1.1.6 Pig scalding and Pig hair and toenail removal
After bleeding and a preliminary cleaning, the pigs are scalded in a scalding cauldron (4
to 6 minutes at approx. 60 °C) or in a scalding sprayer unit (scalding tunnel) in a continu-
ous-flow method. The hairs and bristles loosened in this way are then mechanically re-
moved with a hair-removal machine (rollers with rubber beaters and steel scrapers). In
technically advanced systems, the scalding and the hair-removal can occur simultane-
ously in a scalding hair-removal machine.
After several bouts, the scalding cauldron is emptied for hygienic reasons. This emptying
leads to peaks in the produced wastewater, and the wastewater from the scalding shower
unit is loaded with dripping blood and with pollutants which had been sticking to the ani-
mals. During the hair removal, the carcasses are constantly sprayed with warm water,
which makes for wastewater that is loaded with hair and bristles.
2.1.1.7 Pig singeing
For the ensuing secondary hair removal and surface degermination, the carcasses can
be singed by using gas burners (singeing ovens).
2.1.1.8 Evisceration
The stomachs and bowels produced in the disembowelling of the animals are conveyed
into the evisceration for further processing. In the evisceration, stomach and bowel pack-
ets from pigs and the rumens of cattle are processed.
In advanced evisceration techniques, the largest part of the bowel contents (up to 80%)
are collected separately. In this case, the evisceration wastewater flows to the red line and
is treated with wastewater technology. Residues produced there (for instance floating mat-
ter, fat separator residues) fulfil the substance requirements to be treated in a animal car-
cass disposal plant or in a special plant. The actual processing of the bowels (sorting,
calibrating, etc.) is done in the bowel sorting unit.
The incoming closed rumen packet is first cut open by hand; by turning the packet
around, the rumen contents is coarsely emptied. The contents is collected separately and
often conveyed to the dewatering (yellow line) with a compressed air gun. Water mixed
with compressed air is used for the eventual cleaning of the muscle skin. Following that,