Integrierte Vermeidung und Verminderung der Umweltverschmutzung

Concentration in waste water
Brine pH BOD5 COD Chloride
(mg/l) (mg/l) (mg/l)
Fresh brine 6.0 – 6.2 10000 – 30000 15000 – 40000 12000 – 15000
Fermentation brine 3.8 – 4.2 17000 – 50000 25000 – 75000 2500 – 20000
Blanching brine 3.8 – 4.0 40000 – 55000 65000 – 85000 –
Table 3.30: Waste water values of brine during the production of Sauerkraut
3.3.3.5.3 Frozen vegetables
Chapter 3
Materials handling and storage (A.1)
In manufacturing frozen vegetables, transportation and storage operations require energy as
follows [32, Van Bael J., 1998]:
• the transportation of frozen vegetables requires 2 – 14 kWhe/t frozen vegetables. For most
production lines, the electrical rating of the belts is between 5 – 30 kWe
• the storage of vegetables needs 20 – 65 kWhe/m 3 storage/year electricity and about
26.389 kWh/m 2 (95 MJ/m 2 ) storage/year is needed in the form of hot water.
Data from the literature show that the average energy balance is made up as follows [32, Van
Bael J., 1998]:
• 11 % for the evaporator fans
• 5 % for the condenser fans
• 7 % for peripheral equipment
• 77 % for compressors, of which 21 % is used for heat input via doors/hatches, 48 % used
due to losses via the building shell, and 8 % through the product.
Sorting/screening, grading, dehulling, destemming/destalking and trimming (A.2)
The sorting operation has an electrical energy consumption of 0 – 20 kWhe/t frozen vegetables
[32, Van Bael J., 1998]. Table 3.31 shows the electricity consumption during the sorting of
vegetables.
Product
Electricity consumption
(kWhe/t frozen vegetables)
Spinach 0
Cauliflowers 1
Peas 4
Sprouts 4
Beans 5
Carrots 8
Table 3.31: Electricity consumption during the sorting of vegetables
[32, Van Bael J., 1998]
Peeling (A.3)
In frozen vegetable processing, salsifies and carrots are peeled before being mechanically
processed. Caustic peeling and steam peeling are two methods used. Caustic peeling needs less
energy, both in terms of electricity consumption and steam consumption, than steam peeling,
but creates more load for the WWTP [32, Van Bael J., 1998]. Table 3.32 shows the energy
carrier and consumption for the caustic peeling of vegetables and Table 3.33 shows the energy
carrier and consumption for the steam peeling of vegetables.
RHC/EIPPCB/FDM_BREF_FINAL January 2006 175