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The present paper presents an innovative ecological and efficient method to recover the useful metals from various types of industrial wastes by processing in a microwave field. Compared to the classical methods, microwave melting presents a series of major advantages, such as: i. simultaneous evolution of the heating gradient in the entire volume of material; ii. much higher heating rates that shorten the melting time by 70-85%, thus leading to energy savings and higher processing capacities; iii. superior quality of the obtained materials by reducing the melt impurification through oxidation; iv. remarkable versatility, as wastes with a wide range of shapes, chemical compositions and structures can be processed in the same installation; v. the possibility to neutralize the gaseous emissions also in microwave field. In the present work two types of wastes from the obtaining of aluminum-silicon and respectively antifriction antimony-tin-lead alloys, were melted in a microwave furnace. The values of the metal recovery efficiencies were of approximately 90%. Also, the treatment of the gaseous emissions in microwave field lead to the reduction of the hazardous substances' contents to values under the legal limits. [ABSTRACT FROM AUTHOR]