On the application of the Perrin process for ferro‐alloy production

This paper supplements a previous review of the Perrin process for steelmaking with the same focus on its principles, technology and economics. Metallurgically, Perrin's idea of emulsification as a means of achieving rapid reaction also applies to the production of ferro-alloys. However, the larger proportion of the amount of slag in relation to that of metal makes it necessary to use other procedures for the intimate mixing of the two phases than was the case of steelmaking. Together with the prevailing high reaction temperatures this requirement means that considerable know-how is needed for acquiring regular production. The major application of the Perrin process to ferro-alloys has been for low-carbon ferrochromium, for which it has retained a niche market. To a minor extent it has also been used for ferromanganese and ferronickel. The history and success of the Perrin process for such purposes can be understood in terms of the concept of the so-called development blocks. This resembles the case of steelmaking inasmuch as its inventor has played a decisive role. The complexity and difficulties of the procedures called for an important contribution by his engineering associates