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Automated removal of galvanizing bottom dross

I am looking for an automated or semi-automated mechanical solution to remove bottom dross in a zinc pot of a continuous galvanizing line.

Jerome Mornac
engineering - France
June 20, 2011

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June 28, 2011

Sir:

In your continuous line there would likely be enough aluminum in the zinc such that you would not have bottom dross. The aluminum should combine with iron so that all the dross is top dross. What is your aluminum concentration in your zinc?

I have heard rumors of a continuous drossing machine/method with a ceramic filter. Perhaps it exists, but certainly not well known.

Regards,

Dr. Thomas H. Cook
Galvanizing Consultant - Hot Springs, South Dakota, USA

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To remove the bottom Dross in a CGL plant the Pneumatic Drosser is commonly used. It is widely used.
Till date we have not heard of any automatic or semi-automatic technique to do it.

Umesh Dalela
- Mumbai, Maharashtra, India
August 1, 2011

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Sir:

It is my experience that using an air-cylinder clam is NOT a good way to dross.

A MUCH better drossing method is to use a scoop, "spoon" or shovel which looks like a large capital "T" which is picked up by the crane on both top ends of the "T." On the bottom end of the "T" is mounted the dross scoop. Opposite the scoop is a counter weight on the upper part of the "T."

While in Saudi Arabia I used their clam for several hours an only managed to remove a 1000 pounds of dross, and I mixed much dross into the zinc. The scoop that I designed for them removed several tons of dross (with high iron content) in a few minutes.

Regards,

Dr. Thomas H. Cook
Galvanizing Consultant - Hot Springs, South Dakota, USA
August 2, 2011