ZINC

 

PDF BRUCHURES

 

 

 

 

 

Zinc and its alloys
Engitec built several zinc recycling plants to process the various types of scrap.

The Ezinex Process
Metallic Zinc recovery from zinc bearing wastes from galvanising industry and from unwashed crude zinc oxide.

The Ezinex Technology
EZINEX, an acronym derived from “Engitec Zinc Extraction”, was developed by Engitec in Italy since 1983 when a pilot plant capable of treating 500 tons of EAF dust per year was erected and operated at a major Italian steel mill- belonging to the Pittini Group.
The basis of the process is metallic zinc recovery performed by a hydrometallurgical system. Engitec’s R&D tested various zinc containing materials from different sources like electric arc furnace (EAF) dust from steel works, Waeltz oxides, oxides from converters, zinc ashes.

More about Ezinex Process
The first plant to commercially introduce the EZINEX process to treat the full quantity of EAF dust generated by the steel mill, with a nominal treatment capacity of 12,000 tons per year was commissioned during February 1996.
The EZINEX process is raising great interest in a number of EAF Dust collectors in the world, who see in this technology the most appropriate process to maximize the value of the EAF Dust by producing High Grade zinc metal.

 

The Indutec Technology
Recovery of crude zinc oxide and pig iron from the EAF Dust.

More about the Indutec Technology
The INDUTEC Process is design to treat EAFD and oxidised zinc bearing materials with high Fe content. The INDUTEC Process is based on a low frequency “coreless” induction furnace where the zinc bearing material is appropriately fed with coal and slagging additives. The following results are achieved:
• the reduction of iron oxides to pig iron
• the concentration of zinc and other heavy metals in the fumes leaving the furnace
• the formation of a glassy inert slag
the pig iron bath, kept at the right process temperature and vigorously stirred by the inductive current, is the reducing phase of the process where the heavy meal oxides fed to the furnace are reduced to metal.
The liquid slag, covering the pig iron melted bath, is the oxidising phase of the process where carbon is oxidised to CO while the metals, leaving the melted bath, are converted to oxides and vented out of the furnace by the gas phase.
A gas filtration unit will provide the separation of solids from the gas stream leading to the recovery of a mix of metal oxides, the crude zinc oxide, with a high concentration of zinc. The final concentration of zinc strongly depends on the composition of the feed.
As an example, the treatment of 100 t of a typical EAFD according to the INDUTEC Process the following products are obtained:
• 24-28 t of pig iron
• 32-36 t of crude zinc oxide (Zn=50-60%)
• 32-36 t of glassy inert slag
The slag, that passes the leaching test for non-hazardous materials, was successfully tested for the use in street building and in sandblasting.

 

Copyright by Engitec Technologies spa - Via Borsellino e Falcone 31 - 20026 Novate Milanese (MI) - Italy