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  for Metal Finishing since 1989
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Air Pollution Standard

Dear Sir: We are starting an anodizing facility in San Jose California. Do we need scrubber if we do not deal with solvent, chromium, and chemical polishing?

Charles Lee
- San Jose, California, USA
2000

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That's going to depend on other factors not addressed by your posting. I'd go to the permitting authority for your area and ask. If you aren't using chrome then you are using sulfuric acid, and people don't want acid mists as discharges to the atmosphere.

James Totter, CEF
- Tallahassee, Florida
2000

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2000

Hi Charles, I guess that whenever one is not sure about spending $$$ to obtain air pollution equipment, one way is to phone up, in your case in the USA, the local EPA.

You may get someone helpful. You may get some snotty kid straight from school who will tell you YOU MUST do this and you must do that ... after all, it's not his/her money which would be spent. And said person will 'go by the book' and quote from the Ventilation Manual, which, apart from being the best book of its type in the world, is sometimes out of date and has airflow designs or airflow numbers that would sure work but are bloody expensive as the writer, in many cases, wants to cover his maximus glutinous.

If you are doing any Bright Dip, yes, you'd sure have to have a scrubber. If you are just 'etching' using sulfuric, heck, a scrubber is damned expensive and a good eliminator, l2 micron capture or less (try Munters in Florida or even contact me, if you wish) should do the job most adequately.

By 'eliminator' I mean a two stage bank of PVC or PP vertical blades in a well designed casing using sine curved blades @ 20 mm centres and, say, @ max. 7.7 M/Sec = l,500 fpm design. But this would not be good enough for Bright Dip.

Personally, I'd check around with your suppliers. After all, they'd know the chemicals you are using and should have a good idea if your process should be scrubbed.

If you approach the authorities, the EPA, ie. the bureaucrats, you'll find that they would start telling you WHAT TO DO and that could be quite expensive. In my experience, if a guy actually DOES SOMETHING, even something that is perhaps not to modern air pollution standards, he will stand a far less expensive chance of having to rectify things whereas if you knowingly do nothing at all, you can have the book really thrown at you. ie. expense. ie. bureaucrats with long noses to ensure that YOU are obeying big brother. I wish you luck! I hope that the above is perhaps helpful. Cheers ! Freeman Newton

Freeman Newton [deceased]
(It is our sad duty to advise that Freeman passed away
April 21, 2012. R.I.P. old friend).