Metal finishing Q&As since 1989

-----

Zero Discharge system for electroplating waste

 

I am in the process of setting up a decorative electroplating operation in China. We need to set up a zero discharge system to treat rinse water and spent plating baths. We will be plating copper, nickel, chrome, silver, gold, bronze, and zinc.

I recently heard about electrocoagulation. I was reading some of the older discussions about the topic and the name James B. Long (letters 2318, 4924) appeared several times discussing what sounds like a promising application in PA.

Has anyone heard about the POWELL WATER SYSTEMS performance?

I am trying to evaluate ion exchange vs electrocoagulation.

Has anyone heard anything about HYDROMATIX?

Can any one help with some past experience with these processes or even better has anyone used equipment from Powell or Hydromatix?

Thanks,

Eric Morris
- East Norriton, Pennsylvania, USA

---

 

Hi, Eric. Zero discharge is quite difficult, especially if barrel plating is involved; and electrocoagulation is just one small part at the tail end of it. A good reference is Kushner's "Water and Waste Control for the Plating Shop" [adv: this book on eBay, Amazon, AbeBooks]. We hope your question brings additional technical feedback. Good luck.

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

---

 

Here's some data on an electrocoagulation unit (not made by any of the vendors you mentioned (all values in ppm):

    Raw  - First Pass   - Second Pass
Cr  89.5 - not detected - 0.287
Ni  202  - 45.6         - 1.29
TDS 1320 - 876          - 655

I don't think electrocoagulation by itself will do zero discharge. Maybe think about electrocoagulation followed by IX

James Totter, CEF
- Tallahassee, Florida