Integrierte Vermeidung und Verminderung der Umweltverschmutzung

Chapter 3
For cheese manufacturing, about 90 % of the milk used ends up as whey. Sweet whey is often
recovered and used as a food grade additive. Salt whey, produced after salt has been added to
the curd to remove additional liquid, is not suitable for this application unless the salt is
removed by RO. The RO permeate is highly saline. Unless whey is processed quickly it
becomes acidic due to lactic acid formation. If acid whey is discharged to a WWTP, it may
cause low pH levels.
This waste water has an extremely variable composition, depending on the technology applied
and whether whey is segregated. The characteristics of a typical waste water from cheese
manufacturing are shown in Table 3.55.
Parameter
Installation
with
whey recovery
Installation
without whey
recovery
mg/l
BOD5 2397 5312
COD 5312 20559
Fats 96 463
Ntotal 90 159
Ptotal 26 21
Table 3.55: Composition of cheese manufacturing waste water
[134, AWARENET, 2002]
3.3.5.2 Air emissions
Many dairies produce thermal energy on site. Emissions of carbon dioxide, sulphur dioxide and
nitrogen oxides derive from the energy production in the boiler plants and are not discussed
here. Many dairies still use halogenated compounds in their cooling systems, mostly HCFCs,
but small amounts of CFCs are still used in some countries. The interaction of halogen
refrigerants with ozone in the air has resulted in the progressive prohibition of the placing on the
market and use of ozone depleting substances and of products and equipment containing those
substances [202, EC, 2000]. There is currently a proposal for a Regulation of the European
Parliament and of the Council on certain fluorinated greenhouse gases [246, EC, 2003].
Ammonia used in cooling systems may leak or accidental releases may occur which also result
in odour complaints. Odour problems are usually related to waste water treatment operations.
Dairy installations situated in urban areas usually receive complaints regarding noise, e.g.
associated with vehicle movements, refrigeration and UHT installations.
Bag filters can be used to reduce dust emissions to