To provide a treating method, with which tar content in furnace top exhaust gas caused by imcomplete decomposition of synthetic resins in scrap can be restrained, in the metallic scrap melted in a vertical type melting furnace. 竪型溶解炉における金属スクラップ溶解で、スクラップ中合成樹脂類の不完全分解による、炉頂排ガス中のタール含有量を抑制できる処理方法。 - 特許庁