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Driving force for implementation
Example plants
Teil 3 Seite 8-31
Waste water pre-treatment for Bauerngut Fleisch- und Wurstwaren GmbH, , Germany,
Anaerobic waste treatment of the NFZ pork slaughterhouse in Emstek, District of Clop-
penburg, Germany
Waste water pre-treatment for Bauerngut Fleisch- und Wurstwaren GmbH, Könnern,
Germany, North-Rhine Westphalia slaughterhouse pre-treatment, Waste water pre-
treatment plant, Saxony Anhalt slaughterhouse, Germany
Reference literature
ATV-Handbuch Industrieabwasser (Lebensmittelindustrie)
8.2.4 Physical-chemical methods
As physical-chemical methods for an extensive separation of fat and solids, particularly
floatation methods are used. Flocculation agents, however, are used there only in single
cases.
As with the fat separators, the efficiency degree of floatation plants is reduced by high
temperatures and high pH-values. The method most proof against high pH-values is the
mechanical floatation, where the air supply is achieved via especially developed sub-
merged floatation aerators.
The following table shows the purification performance of an installed floatation plants
for the unequalised wastewater of a TBA.
Table 8-2: Influent and effluent values of a mechanical/physical-chemical preliminary
wastewater treatment plant
Parameter Influent Effluent Increase/Decrease
%
pH 9,0 - 9,5 7,7 - 11 -
Filterable solids mg/l 1.530 570 - 62,7
COD total mg/l 5.024 3.416 - 32
Fat mg/l 1.590 199 - 87,5
NH4-N mg/l 943 648 - 31,3
org.-N mg/l 119 39 - 66,9
Stripping
Stripping can be used mainly at a high efficiency degree and a high economic feasibility
rate for the treatment of the hot exhaust vapour condensates. Because of the low waste-
water volume flows, however, stripping can also be used for the mainstream.
The following example of a stripping plant in the part-stream on an industrial scale with
exhaust air treatment in a bio-filter shall serve to describe the purification performance.