| 摘要 |
PROBLEM TO BE SOLVED: To manufacture inexpensively a sound insulating material having the optimum sound insulating characteristic and permit the recycling of natural resources, thrown away wastefully conventionally, by a method wherein a useful metal is taken out of discharged slag from a melting furnace and the grain size thereof is regulated to constitute the same so as to use for a raw material of the sound insulating material. SOLUTION: Municipal waste (general waste) including metallic matters, such as steel cans and the like, is cut and crushed so as to have a predetermined size and, thereafter, the municipal waste is charged into a melting and gasifying furnace 10 together with coke and limestone to burn and melt them therein. The metallic constituents, oxides and the like are molten and reduced by the coke to produce molten slag including metallic constitutes. Next, the molten slag is crushed employing a water crushing device 20, then, the crushed matter is passed through a magnetic selector 21 to collect granular matter (magnetized matter), including iron, nickel and other metallic constituents. The granular matter (magnetized matter), selected through magnetic selection, is charged into another crusher 21a to obtain rounded solid granular matter to permit the utilizing of the same for the adding constituent of the sound insulating material (soundproofing material). |
