*2.1. The Coal-Gimbal Distributor*

The mathematical model for the coal-gimbal distributor is similar to the chute distributor of a modern BF with the bell-less charging system (cf. Figure 3). In the mathematical model, the charging process is divided into four consecutive fundamental steps: the free falling of particles from the hopper onto the chute, the sliding of particles along chute, the free falling of particles from the chute tip, and the formation of the burden pile. Detailed treatments of the first three fundamental steps can be found in a previous publication [18,19] of the authors. In the fourth step, compared with the charging process of BF, the burden has a longer descent distance and a wider flow width in the COREX charging process, so the formation mechanism of burden pile is quite different.

**Figure 3.** Schematic illustration of coal-gimbal distributor.
