UTILIZATION OF METAL SUBSTANCE FROM FOUNDRY DUSTS

11th International Multidisciplinary Scientific GeoConference SGEM2011, www.sgem.org, SGEM2011 Conference Proceedings/ ISSN 1314-2704, June 20-25, 2011, Vol. 3, 925-935 pp

ABSTRACT

The foundry industry, itself, is one of the world´s first recyclers. Foundries have been
making new metal objects by remelting old ones. An estimated 15 to 20 million tons of
scrap metal that would otherwise be sent to overcrowded landfills are being remade
into new castings each year.

As with most industries, the foundry industry generates its own by-products. Typical
by-product streams from the foundry industry include foundry sand, foundry slag,
baghouse dust, and furnace and ladle refractory.

In order to control particulate emissions from foundry operations, foundries use
conventional wet scrubbers and dry baghouse collection systems. Typical foundry
operations that require some form of air pollution control for particulate emissions are
melting, pouring, cooling, shakeout, and grinding and finishing. The nature of the dust
collected is a function of the foundry operation that generates the dust.

Dust with metal content is generated in furnaces, by finishing operations and by
grinding of castings. Cupola or electric arc furnace dust contains iron in the form of
oxides, dust from finishing operations and from grinding contains iron in metal form.
FeO content in cupola furnace fly dust contains around 20% FeO, iron content in the
dust from finishing operation is approximately 40% and from castings grinding around
80%. Main goal of this contribution is utilization of metal (iron) from these three kinds
of dusts by cast iron castings production.

Keywords: foundry dust, metal content, fly dust, short blasting, grinding