EOW May 2007

english

V z fresh water feed

Pickling Pickling Water

Water Activation Phosphating Water Neutralisation Lubricant

acid

acid

rinse

rinse

rinse

Figure 4 : Cascade rinse

s

In a two-stage cascade rinse the water consumption with the figures of the previous example is reduced to

V

= 0.1 x 2

200/1 = 1.4 l/m 2

Z

3. Surface Treatment Line layout wire or tube mill

Figure 4 (see above) shows a cascade rinsing including all rinse tanks after pickling as well after phosphating.

This is the most economical method for water savings.

Tank C 1

is quite often a spray rinse in wire

treatment lines.

Additionally the water from C 1 is used for the bath replenishing of pickling tank 2. Pickling tank 1 is replenished with the acid from tank 2. The acid savings with this so-called cascade pickling reach about 30%. n

By K D Nittel , Chemetall GmbH, Trakehner Straße 3, D-60487 Frankfurt/M, Germany Tel : +49 69 7165 0 Fax : +49 69 7165 3018 Website : www.chemetall.com

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EuroWire – May 2007