Due to the rising costs for fresh and wastewater, the treatment and reuse of low-contaminated process water
streams from food processing companies is increasingly gaining in importance. In this study it was shown that water
for reuse could be produced from this water by a specific treatment using membrane processes while achieving
reduction of water consumption and wastewater quantities. Three examples of low-contaminated wastewater will be
discussed: firstly a vapour condensate from milk processing, secondly chiller shower water from the meat processing
industry and thirdly wash water from bottle washing machines. Due to the promising laboratory and pilot-scale
experimental results, a demonstration plant with a capacity of 1-2mVh, consisting of the following stages, was set
up: pretreatment; main treatment - - 1st nanofiltration stage; post-treatment - - 2nd nanofiltration or low-pressure
reverse osmosis stage and UV water disinfection. Economical water treatment was possible in all three examples.
The treated low-contaminated process water from chiller showers or bottle washing machines was of drinking quality
and therefore suitable for reuse. Alter treatment, the vapour condensate could be reused as boiler make-up water
which is subject to higher standards than drinking water. The experimental technology underwent an authorization
procedure at the Saarland Ministry for Health, Germany, and was granted approval.