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Pollution control measures for chrome plating

We are hard chrome platers on a very large scale and wish to keep our premises eco friendly with proper pollution controls.Any suggestion regarding the said matter is welcome.

Ravindra Sant
- Ambarnath, India
2000

Hi Ravindra !

Good for you! I like people who want to do something about cleaning up the environment. However, at the same time let's be practical, let it not cost very much, let it also contribute to acid recapture, let it be easily maintained, let it be fairly compact, too.

Firstly, please go the 'front page' and have a look at item # 7 in the On-Line Library on 'Hard Chrome Plating - Materials to Consider.'

I am suggesting an inertial approach. A so-called mist eliminator using a very good blade design (there are other blade designs around, some of inferior design and some units of questionable fabrication 'quality' as far as the casing design (very, very important!) is concerned as well as the important design velocity).

The gut standard 2 stage chromic dry scrubbers (so called because one, hopefully, would use LESS wash-down water than the drag-out and evaporative losses and recycle the chromic back to the tanks) was measured @ around 0,35 grains/l000 cfm in British Columbia where in the 80's the allowable limit was ll grains, ie. 30 times LOWER than the permit requirements. These were very successful and not too expensive, either. Test data is available. However the above 0.35 figure equates to only around 0.8 mg/MĒ.

In the USA they have now a very onerous, a too onerous, I feel, spec. of around 0.05 mg/MĒ. This has been attained using some other techniques and a more advanced but, obviously, an inertial scrubber that costs more and has a higher pressure drop.

I hope that this is of some help to you.

Cheers !

Freeman Newton [dec.]
R.I.P. old friend (It is our sad duty to
advise that Freeman passed away 4/21/12)

There is a wealth of information out there if you take the time to find it. I'm going to suggest two resources here: first, try searching the US EPA web site at www.epa.gov. There has been a lot of work done in the area of pollution prevention for chrome platers by them, and a simple search will yield a lot of information.

Second, try www.nmfrc.org^*
You might have to spend a little money for a subscription, but the amount of information you get will be worth it.

James Totter, CEF
- Tallahassee, Florida

Ed. note: * We at finishing.com will just sit here quietly biting our tongue.