Uddeholms Aktiebolag

Rune H Lindstrom

Lars-Gunnar Norberg

M K Johnsson

Owe G Larsson

Bo L Jonsson

Per-Ake Lundstrom

Method of taking care of the contents of valuable metals in grindings and other waste products of superalloys. The material is led into a metallic melt, preferably by injecting it by means of a carrier gas. The charge is heated up in the inductive way. The material contains aluminium and/or tantalum, or can these elements be added separately to the charge, thus preventing an oxidation of such valuable metals as vanadium, tantalum and niobium and obtaining a high yield of these elements. After the remelting, aluminium and/or titanium can be selectively oxidized by injecting into the charge oxygen and/or water vapor, a slag having a certain oxygen potential or a metal oxide where the metal has a lower affinity to oxygen as compared with aluminium and/or titanium.

Method for taking care of metallic waste products by remelting

A process for the production of ferro alloys containing manganese, chromium, molybdenum, and small amounts of carbon is provided. To a converter having a previous product melt and a slag rich in oxides of chromium or manganese is added a reducing agent having an excess of silicon or aluminum. Fluid is injected into the melt to create intensive agitation of the melt, slag and reducing agent, whereby the oxides in the slag are reduced. Lime is added to fix the resulting silicoc acid or aluminum oxide, and the slag with reduced chromium or manganese content is removed from the converter. Injection into the melt of a pulverulent oxide concentrate of chromium or manganese is continued, with additional lime, until the excess of silicon or aluminum in the melt, supplied by the reducing agent, reduces the injected oxide concentrate and the chromium and manganese are oxidized and go into the slag. The resulting product is partially tapped from the converter and the process is repeated.

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Hagfors, Sweden

Rune H Lindstrom