Reclamation of metals from magnet alloy grinding sludge.
Recycle and secondary recovery of metals: proceedings of the International Symposium on Recycle and Secondary Recovery of Metals and the Fall Extractive and Process Metallurgy Meeting, December 1-4, 1985, Fort Lauderdale, Florida. Taylor PR, Sohn HY, Jarrett N, eds. Warrendale, PA: Metallurgical Society, 1987 Feb; :327-336
The Bureau of Mines has devised a procedure for treating cobalt-nickel-bearing magnet alloy grinding sludge to remove detrimental contaminants and produce an alloy powder for recycling. Sulfur contamination can result from use of elemental sulfur as fixturing cement for grinding. Carbon contamination results from residual oil and grinding-wheel debris. Since magnet alloys have low tolerances for these elements, they must be removed to low levels to render the metallics recyclable. The patented technique consists of (1) treatment with solvent to remove most of the sulfur and oil contamination, (2) drying, light grinding, sizing, and magnetic separation of a major portion of the grinding media, (3) controlled oxidation roasting to remove residual sulfur and carbon, and (4) hydrogen reduction of metal oxides. The powder product contained about 0.01 pct S, 0.06 pct C, and 30 pct Al2O3. When added to an experimental AlNiCo melt, the alumina floated to the slag. Overall, >95 pct of the CO, Ni, and Fe and approx. 90 pct of the Cu were recovered from the starting sludge sample.
Metals; Metallurgy; Metallurgical-processes; Waste-treatment
OP; Conference/Symposia Proceedings
Taylor-PR; Sohn-HY; Jarrett-N
Recycle and secondary recovery of metals: proceedings of the International Symposium on Recycle and Secondary Recovery of Metals and the Fall Extractive and Process Metallurgy Meeting, December 1-4, 1985, Fort Lauderdale, Florida