Club 3000 - Ohio Landfills

What is aluminum dross?Aluminum dross is a waste product produced when refining aluminum. It consists of metal, salts oxides, and other non metallic substances. Dross is classified as either black or white dross. Black (or dry) dross has a lower metal content and higher amounts of oxides and salts. It tends to be in granular, like sand. White (or wet) dross has an extremely high metal content and smaller amounts of oxides and salts. It tends to form into large clumps or blocks.

What is saltcake?

Saltcake (or salt slag) is a hazardous waste produced in a rotary furnace where aluminium waste is melted under a layer of salt. It is basically salt combined with aluminum dross.

Why are dross & saltcake a concern?

Saltcake contains contaminants like oxides, carbides and sulphides as well as metallic aluminium which is entrapped in the salt and traces of pollutants polychlorinated dibenzo-p-dioxins and dibenzofurans (PCDD and PCDF).

In contact with water it emits flammable gases such as acetylene (which in turn can cause explosions), and is liable to give off toxic gases, such as ammonia, in dangerous quantities.

Sources:
Australian Government - Department of the Environment and Water Resources
Characterizing the Physical and Chemical Properties of Aluminum Dross - Article by O. Manfred, W. Huth, and I. Bohlinger (PDF format)