ALTA 2014: Mathematical modeling of sulfide concentrates pressure oxidation using laboratory kinetics
Currently there are several widely used kinetics models for pressure oxidation of sulfide concentrates, each one having its own advantages and disadvantages. In this work we used the kinetics function model developed by EM. Vikdorchik and AB. Sheinin. Based on this model the kinetic parameters for 13 concentrates were calculated for the temperature range 190-230°C and oxygen partial pressures 0.3-0.9 MPa. The concentrates differed in pyrite, arsenopyrite and pyrrhotite content. For each material the following kinetics parameters were calculated — kinetic function, reaction order, activation energy.
The rate-limiting step for all materials were chemical reactions. AII activation energies were within the range from 40 to 90 kJ/mol. The reaction order for concentrates with overrepresentation of pyrite and arsenopyrite ranged from 0.7 to 1.0. For concentrates with overrepresentation of pyrrhotite it ranged from 0.6 to 1.
It has been shown that these kinetics characteristics and kinetic function can be used for modeling a continuous process. The resulting mathematical model quite accurately describes the results of pilot plant tests.