PETpla.net Insider 06 / 2013

WATER TREATMENT 34 PET planet insider Vol. 14 No. 06/13 www.petpla.net Water treatment and water management as key themes at drinktec 2013* Of the first water All the major international brewing and soft drinks groups have long since formulated ambi- tious goals for reducing their ‘water footprint’, none of which would be achievable without in-company water recycling. Water treatment and water management will be key themes at drinktec 2013 in Munich, between September 16 and 20, 2013. “Sustainability most certainly also affects the subject of water process- ing. Savings that only a few years ago were considered too small and not cost-effective to implement, are now becoming ever more interesting. I am thinking here, for example, of the pro- cessing of water from filter backwash and of further increasing the yield in reverse osmosis plants. Also, intelli- gent control and monitoring strategies will start to become more important.”, this is how an expert, Professor Dr. Stefan Schildbach from the Univer- sity of Fulda, Germany, Dept. of Food Technology, describes the current situation. The membrane trend What, then, does this mean for the separation technology being used? “For some years now the trend has been clearly towards membrane sepa- ration. That applies both to reverse osmosis for desalination of water as well as to the area of filtration,” explained Wolfgang Winkler, Techni- cal Managing Director at EUWA H.H. Eumann GmbH. There are good rea- sons for this development: Membrane systems operate fully automatically and continuously, they need virtually no chemicals and the waste water from water preparation has no added salt from regeneration media. Added to this is the fact that the membranes have become cheaper and more effective and the necessary pressure and therefore energy input is now much lower. Ion exchangers and lime precipitation still have a place However, there are still applica- tions in which the ion exchanger or even the most traditional of all preparation methods – lime precipita- tion – will be fully justified, as Winkler points out: “Lime precipitation has very low operating costs and very low wastage given, for example, the right composition of untreated water. In water treatment plants with a standard 20-year lifespan, these two factors are of considerable importance. In addition, lime is a natural product. Lime precipitation can therefore be an attractive alternative for businesses following strictly organic guidelines, or for tradition-conscious craft breweries. Until now, however, the vessel sizes necessary for lime precipitation have been a disadvantage, in particular in view of current steel prices. We have therefore combined lime precipitation with membrane filtration, so do not need these vessels and we operate fully automatically.” Regenerating with the sun Experts continue to see potential in electrodeionisation (EDI) which is currently being used, for example, in semiconductor production as the final polishing stage in the preparation of ultrapure water. In the EDI process the ions in the drinking water are sepa- rated off via an exchange resin system. At the same time a DC voltage is applied, which gives rise to H 2 O + and OH - ions which continuously regener- ate the resin. This regeneration is also the reason why it is believed the pro- cess will soon find new applications. Because the DC voltage needed for regeneration can be generated easily with photovoltaics, this represents a further step in the direction of autono- mous production. Membranes also at the “end-of-pipe” Modern water management does not only mean ensuring enough fresh water is prepared. It also means sepa-