Integrierte Vermeidung und Verminderung der Umweltverschmutzung

Chapter 3
Flume water
Raw produce
storage
Washing
Peeling
Grading,
trimming,
size reduction
Blanching
Water cooling
Freezing
Boiler blowdown
Waste water from
cleaning activities
Gross solids, TSS, BOD/COD (from detergents),
pesticides
Gross solids, TSS, BOD, COD, high pH
(caustic peeling)
Gross solids, TSS, BOD, COD
TSS, BOD, COD
TSS, BOD, COD (if water in contact with
produce)
Solids, BOD, COD (de-frost water)
Gross solids, TSS, BOD, COD
TDS
Gross solids, TSS, BOD, COD, high/low pH, cleaning
chemicals
Figure 3.7: Waste water produced in fruit and vegetable processing
[13, Environment Agency of England and Wales, 2000]
Waste water
To sewer or treatment
The incoming produce is washed in chlorinated water to remove residual soil, stones and other
debris and to reduce the microbial population. Large volumes of chlorinated water are required,
especially for root vegetables which carry a lot of earth, and leafy vegetables which have a large
surface area. Mechanical or air flotation techniques are used to aid soil removal and reduce the
quantity of water used. Some recirculation or re-use of water from other operations is common.
Waste water from pre-washing mainly contains field debris and soil particles with small
fragments of the fruit or vegetables. If detergents are used to increase cleaning efficiency, they
contribute to the COD of the waste water.
168 January 2006 RHC/EIPPCB/FDM_BREF_FINAL