1. Design

Large wet process furnaces (e.g. capacity: 3,000 t/d; diameter D: 6.3 m, length L: 227 m, resting on eight supports) gave way, in the 1980s, to dry process furnaces resting on three supports, equipped with a precalciner which, for the same production, have the following dimensions (figure 1 a ): D: 4.20 m; L: 60.00 m.

More recently, a further step has been taken by proposing a reduction in the length of the furnace so that it rests on two supports instead of three; the L/D ratio is then reduced from values between 14 and 18 to values between 10 and 13, for the same production capacity (figure 1 b ): D: 4.40 m; L: 48.00 m.

At the same time,...