Primary smelting - Ichiji smelting

...Direct smelting has fewer steps, so it has the potential to reduce energy and labor in the smelting process, and has been the subject of extensive research in order to innovate current smelting methods. However, it is usually difficult to overcome drawbacks such as the difficulty of process control, the decline in product yield (the percentage of the metal contained in the raw material that can be extracted as a product), and the decline in product purity. Indirect smelting is common for industrially produced metals, and is composed of two or more stages of processes such as primary smelting (crude smelting, concentrating the target metal) and secondary smelting (refining, producing pure metal). (2) Dry smelting and hydrometallurgy A smelting method that uses an aqueous solution is called hydrometallurgy, and a smelting method that does not use an aqueous solution and uses high-temperature chemical reactions is called dry smelting. ...

*Some of the terminology used to refer to "primary smelting" is listed below.

Source | Heibonsha World Encyclopedia 2nd Edition | Information

…直接製錬は工程数が少ないので，製錬プロセスの省エネルギー化，省力化の可能性を秘めており，現行製錬法の技術革新のために広く研究の対象となっているが，プロセス制御の困難，製品歩留り(原料中に含まれた金属分のうち製品として採取できた量の割合)の低下，製品純度の低下などの欠点の克服が通常難しい問題となる。工業生産される金属では間接製錬が普通で，一次製錬(粗製錬，目的金属の濃縮)と二次製錬(精製，純金属の製造)などの2段階以上のプロセスで組み立てられている。(2)乾式製錬と湿式製錬　水溶液を利用した製錬法を湿式製錬，水溶液を用いないで，高温化学反応を利用した製錬方式を乾式製錬と呼ぶ。…

※「一次製錬」について言及している用語解説の一部を掲載しています。

出典｜株式会社平凡社世界大百科事典 第２版について | 情報