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  for Metal Finishing since 1989
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Pollution free Galvanization

1998

Is there such a process? If so how exactly is it achieved. I'm referring specifically to air emissions and effluents.

My client is setting up a new hot dip galvanizing process using Zinc ammonia ⇦this on eBay or Amazon [affil links] Chloride at 450 C. I would be very grateful if you could advise me or direct me to a source that knows.

By-the-way, I was amazed by your Web Site. I think you're providing a great service.

Many thanks,

Perry Davies
- Environmental Management Consultant

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Ed. note: Thank you for the generous words, Perry.

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It is possible to recover the fluxing bath through addition of ammonia. This will increase pH (should not be more than necessary for precipitation of iron) and produce NH₄Cl. Since Zinc is provided through drag-in, savings can be achieved - it is not necessary to buy zinc ammonium chloride any more.

Best regards

Kristian Bierring Lauritsen
- SIRIM
1997

It may be worth looking into the new developments involving the adjunction of Bismuth (Bi), a thoroughly safe metal despite its "heavy metal" status, to improve Zn drainage. Bi presents no environmental problem. Consequently, it is is not subject to any limitations. The developments referred to are from Noranda (Canada) and Union Miniere (Belgium). As Bismuth Institute we are dedicated to promote better knowledge of the element for a more rational utilization. Our publications and services are absolutely free of charge. Just contact me and I will be able to go into details. It is worth underscoring that Bi is approved for, and used in, cosmetics, pharmaceuticals, food handling equipment, plumbing fixtures for drinking water systems, and a host of safety-related applications where a safer alternative to lead is sought or mandated by law. Bi definitely is an environmentally-minded element. Looking forward to be of service.

Yves Palmieri, Secretary General
BISMUTH INSTITUTE -Belgium
1999

i want to know the process & plant drawing of galvanizing. . please give me all information regarding to recovery of zinc in effluent.

khalid ashraf
general marketing - Dubai, UAE
2000

I need to have information about the scientific part of Galvanization (Hot and Cold Dipping) and Electroplating. I hope you can help me. Best regards.

Omar L. Hassouneh
- Amman, Jordan
2000

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I would like to know the effects of metal galvanization on the environment.

Thank you,

Ahmad Mohammad Bahgat
- Cairo, Egypt
2003

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December 19, 2008

Hello gentlemen. The original question seems to have been well answered. Unfortunately, the last three questions are too broad to answer in a response of practical length, which probably explains the long time these questions have stood open with no readers responding.

Khalid, there are some good books on galvanizing, and I think that's where you'll need to look for plant drawings and details. "Hot-Dip Galvanizing: A Guide to Process Selection and Galvanizing Practice" [adv: link to this book on eBay , Amazon, AbeBooks affil links] by M.J. Hornsby sounds very promising and economical.

Omar, in addition to the above book as an introduction to galvanizing, you ask about electroplating. I think either the Metal Finishing Guidebook, or the Electroplating Engineering Handbook [on AbeBooks or eBay or Amazon affil links] would serve you well on that score.

Ahmad, your question is somewhat philosophical. You need to define for yourself whether you mean the effluent from a well run shop, or the effluent from a poorly controlled shop, or an overall energy/carbon/environmental impact balance as compared to some specific alternative surface finishes.

Good luck and Regards,

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