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Treatment of Fe-Zn-Al alloy in top dross

Have used top dross from galvanising plant. Have found this Fe-Zn-Al alloy does not melt but stays as a sludge. can anyone suggest method to fluidise this alloy? i.e. to make it liquid.

M Daver
- Mumbai, India
2006

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2006

DEAR MR DAVAR
Your question is incomplete, please write composition of dross % age inclusive of ZnO, Zn, Al Pb, How melting was done, duration of melting, temperature of sludge etc. Based on your authentic & confident data some suggestion may be given.

Regards,

Dr Pradeep Kumar Maitra
- Chhattisgarh, INDIA

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Dear sir

Thank you for your response. The analysis is as under :
Al = 2.7% ; Fe = 0.7% ; Pb = 0.05% ; balance zinc 92% in metallic form.

The above was melted in a crucible in a molten layer of zinc, temperature around 700 C. Have tried to add fluxes but no results achieved. The resultant sludge is not smooth like metal but like agglomerated crystals.

Await your reply.

M Daver
- Mumbai, India
2006

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Dear Mr DAVER,Sorry for the delay .I believe You are maintaining Pb layer at the bottom of your kettle, if so how it is possible to have 0.05% Pb With 92% Zn ?.The chemistry of top dross(ash) should be correctly determined first, prior to the recovery.
Regards,

Dr Pradeep Kumar Maitra
- Chhattisgarh, INDIA
2006

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2006

Dear Mr Maitra

Thank you for your response. The analysis given is correct. The Pb content is correct as this is top dross and and Pb content is low.

Please help us how to treat the alloy ?

Regards,

M Daver
- Mumbai, India