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Filtration system for high volume Electroless Nickel tank

We are putting in a new electroless Ni plating tank. Also the volume of the solution is not unusual for the industry (450 US Gal), it is for us: we are presently working with 100 - 150 Gal. tanks. This is a regular (acidic) Ni-P (hypophosphite as a reducing agent) solution. We are planning to use a stainless steel tank and plate heat exchanger for heating. Not decided yet on a filtration system. Anyone has experience with horizontal disk filters on Electroless Nickel?

We would like to have a filtration rate of 5000 - 6000 Gal/hr (when the filter is loaded) and at this rate I do not know of a better arrangement as precoated horizontal disk (type supplied by MEFIAG). Remains unknown what kind of filtration media would resist the temperature, would not contaminate the bath and will allow for stripping (if necessary) with 50% nitric acid.

Other suggestions?

Any information, comments and/or suggestions will be greatly appreciated.

Max Stein
captive metal finisher - Montreal, Québec, Canada
1998

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For general practicality, electroless nickel is usually filtered with bag filters inside the tank. This allows for very high volume filtration, and an absolute minimum of support structure subjected to high temperatures, possible plate out, and requisite stripping.

This means the tank has to be a bit oversize to allow space for the internal bag filters, but it is the most common approach anyway.

Ted Mooney, P.E.
Striving to live Aloha
finishing.com - Pine Beach, New Jersey
1998