Saltcake is the slag generated during the recovery of aluminum in Rotary Furnaces. To maximize metal recovery, a salt flux is often added to aluminum scrap and dross in the recovery process, and the residue resulting from that aluminum recovery process is referred to as saltcake or saltslag. Saltcake typically contains 3-10% metallic aluminum, 20-60% aluminum oxide, and 20-80% salt.
If disposed without further processing, saltcake or salt slag can be safely transported and disposed in non-hazardous landfills, when proper care is taken and material handling guidelines are met. However, uncertainties regarding what saltcake is and its proper handling have led to an uneven approach to management practices as well as differing regulatory responses.
Therefore, the Aluminum Association is providing the following information regarding saltcake management in order to ensure that both the aluminum industry and the waste industry manage saltcake responsibly.