Simulating particle agglomeration in the flash smelting reaction shaft

Evolution of Size and Chemical Composition of Copper Concentrate Particles Oxidized Under Simulated Flash Smelting Conditions

“…It has been reported [9,11,16,20,28,38] that the finest particles in the concentrate cause a number of operational problems during flash smelting operation because they tend to form aggregates during feeding. Such aggregates are kept together by weak interparticle forces, such as van der Waals and electrostatic forces.…”

“…On the other hand, such collisions will be effective as long they create new particles. [28] Furthermore, the reaction path shown in Figure 20 will most likely occur with the finest particles in the feed, which are rapidly heated up by its surroundings and reach its melting point within a short distance from the reactor entrance. Figure 21 shows a summary of the experimental data obtained in this work and those found in the literature for the oxidation of copper concentrate particles.…”

“…In an industrial flash smelting facility, it is likely that the mechanisms shown in Figures 1 and 20 occur simultaneously depending on the history followed by the particles and the local conditions in the reactor. [27,39] As current mathematical models of the flash smelting process [28,29,36,37,[40][41][42][43][44][45][46] typically assume a single reaction path followed by the particles, this issue represents an opportunity for their further improvement. Finally, few data points in Figure 21 lay within area III located at relatively large values of fraction of sulfur eliminated (0.5 to 0.7) and size ratio values greater than unity.…”

“…However, the authors did not report on the details of their calculations and the order of magnitude of both quantities. Higgins et al [28] developed an axisymmetric mathematical model of particle agglomeration in the reaction shaft of a flash smelting reactor. The model assumed that collisions occur between pairs of particles with a rate which depends on the turbulent kinetic energy of the particle-gas suspension as well as the sizes, local number densities, and local velocities of the colliding particles.…”

“…The experimental measurement of the size changes along the trajectory of the particle population is relevant because it may provide additional clues on the reaction path followed by the particles during flight. It may also provide experimental data to validate fundamentally based mathematical models of agglomeration [28] and fragmentation [29] phenomena. Based on preliminary tests on this matter conducted in this laboratory, [30,31] the goal of this investigation was twofold.…”