Metal finishing Q&As since 1989

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Reduction of fumes emission

What are the ways of reducing the emission of acidic fumes from the tank house of the zinc electrowinning? The zinc and acid content of the feed electrolyte is maintained at round 60 and 150 gms per ltr.

G Balaji
- Visakhapatnam, India
2002

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2002

Hi G.B. !

Ah, you don't give one enough info ... maybe you should have given us the size of your tank house.

Assuming that this is a LARGE tank house then please consider a directional airflow system ABOVE the operators and the tanks, ie. no separate fumehoods at all.

This consists of a thin or narrow airstreams but quite wide blasting off horizontally. At the other end of the plant or tank house is a collection system, ie. holes in the wall leading into a duct header and into a fan.

The idea is to get the fumes to rise and be swept away by the force of the 'pushed' air and into the 'other' end and not to fall back down. Whether or not this also calls for cleaning/scrubbing the air depends on your environmental requirements. If so, then use a high efficiency blade type mist eliminator constantly sprayed.

Another option, presuming you have a highish flat roof, is to have the fan roof mounted and connected to a main duct header with take-offs leading down to 'holes' in the roof. Typical galvanizing plant set-up. But there you'd need an inertial scrubber again, well, you would in this country.

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