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Airborne emissions calculations: Emissions factors?

Greetings!

I am an engineer working on the scale up of a small barrel plating line to something much larger and more manufacturable. I have very little experience in dealing with the permitting processes required by various local/state/federal regulatory agencies, but I'm learning fast!

In order to complete a Request For Determination, I need to estimate the airborne emissions the process will generate. It seems that the easiest way to do this is by the use of 'emissions factors', estimates made by other people and in other circumstances that can be scaled to my own process. Unfortunately, the only factors I seem to be able to find that are relevant to electroplating, are for chromium plating. I am plating copper/nickel/gold.

Does anybody know of a resource for emissions factors that might be relevant to my situation? Can anybody offer estimation techniques that might do if factors are not available? I am using proprietary formulations for the most part, and was quite shocked to discover that the manufacturer of these formulations does not have factors already developed. It's very difficult for me to do something like a vapor pressure calc estimate when the manufacturer will not tell me the exact composition of the chemistry. Anything that sets me down the right path would be very much appreciated.

Thank you for your help.

Matthew Brown
Engineer - Endicott, New York
2004

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2004

Sorry to follow up on my own question, but I've done a little digging and want to redefine my request.

I waded through some of the EPA documentation, much of which is referenced in answers to questions similar to my own that have been asked here over the years. There is a formula given to calculate emissions from non-chromium electroplating sources in AP-42 Section 12.20 (The link to this document has been given multiple times but it apparently moves a lot, because they are all dead. Here it is again: http://www.epa.gov/ttn/chief/ap42/ch12/final/c12s20.pdf

In any case, the units that the given equation leaves you with are grains/dscf. I have two problems with this:

A)How do you convert grains to a more manageable unit, like lbs or kg?
B)What the heck is a dscf?

Normally what one would do at this point is take the factor that the equation gives you and scale it by using the through-put of the process (and possibly by the surface area of the bath as well. But since I have no idea what a dscf is, I'm at a loss.

Thanks for the help,

Matt Brown
Cable - Endicott, New York

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Hi Matthew,

Any competent Company specializing in air pollution problems should be able to help ... I'd try a local plastics fabricator who can prove that they had solved ventilation problems.

There is a good book, the American Ventilation Manual. Large. Not cheap. But, depending on the process, it suggests the correct airflows. If anything the given data is generous (compiled by engineers who want to cover their posterior).

So your 'emissions' will depend on the right airflow, the right hood design ... and now we go to 'capture' where, in your case, I'd have thought that an extremely well made/designed horizontal flow blade type mist eliminator should solve your problem for a mere 1" of SP. I wouldn't have a single clue about vapour pressure determinations ... but do have over 3 million cfm of scrubber applications, mostly highly successful using ordinary, as above, and also more refined mist eliminator inertial scrubbers.

Freeman Newton [deceased]
(It is our sad duty to advise that Freeman passed away
April 21, 2012. R.I.P. old friend).
2004

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2004

Below is a response to your two questions:

1) Conversion: grain (gr in UK, no US symbol) to kg: 6.479891E-5 (1/7000 lb)

2) dscf = dry standard cubic foot

Rick Hall
Design and Integration of Wet Processing Systems - Hickory, North Carolina, USA