Treatment of Wastes from
Meat Flour Factories
DR. ING. RANIER BORN, Leader
Development Division Ruhrverband
Essen, Germany
INTRODUCTION
In Germany the removal of all accumulating carcasses is regulated by a law since
1939 relating to contagious diseases. Simultaneously this applies to all carcasses
accumulated by emergency slaughter which cannot be used as food. The treatment
of a carcass is carried out in factories producing mainly meat flour as fodder. Their
equipment permits single animals or complete herds suspected of epidemic to be
delivered and slaughtered.
During the last several years initial waste blood from slaughter houses has had
to be additionally treated. The slaughter houses no longer discharge the blood into
the sewer system, as this would cause disturbances to the biological wastewater treatment plant. Today this blood is discharged by a special network and stored in
collection tanks which are regularly collected by transporters for transport to the
meat flour factories.
OPERATIONAL SCHEME
Figure 1 shows the most important production points of meat flour factory and
the places of wastewater accumulation. The wastewater can be divided into two main
groups, corresponding to two separate parts of the plant.
Group A:    Wastewaters with pathogenic germs, which can be regarded as hygenically
dangerous.
Group B:    All other wastewaters accumulating in the plants.
Under Group A are the rinse and cleaning waters
from the slaughter room, the storage room, the
truck cleaning and the skin store. These wastewaters must be thermically disinfected before
being mixed with group B for biological treatment.
In order to guarantee maximum security the
sterilizer simultaneously acts as collecting tank,
which can be emptied only at a certain excess
pressure, e.g. 0.5 at 7.1 psi.
The production wastewaters of Group B are
either sterilized during the cooking process or
solely mixed with sterilized material, e.g. during
cleaning of the equipment.
The specific BOD-loading and the specific water quantity of 1,000 kg (1.1 short
tons) raw material varies according to the applied procedure.
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