Abstract The simulation process was applied to the industrial circuit of the Juruti Bauxite Mine using mathematical models calibrated for the equipment and based on information from industrial sampling. The sampling campaign, mass balance routines and quantification of the process efficiency were discussed in Part I of this study and the model calibration and simulations process were the Part II objective. Simulation scenarios were defined considering the possible particle size curves for feeding the plant. Based on the simulated results, it was possible to observe which operations may be impacted by the increase in production, impacting the percentage of contaminants in the final product, indicating the necessity of equipment interventions to support increases in capacity. Another group of scenarios were established with the objective to evaluate the possibility of increasing the mass recovery and improving the quality of the fine product, by variations in the opening diameters of the apex and vortex finder of the five cyclone stages. Considering the simulated scenarios, the points of attention identified in the simulations were: (a) the washing efficiency could be reduced, in view of a consequent reduction in residence time connected to the change in characteristics of the ore fed to the plant; (b) increase capacity of the primary and secondary screens need to be done; (c) to keep the classification efficiencies, it is necessary install more cyclone units; and (d) changes in the apex diameter and vortex finder could generate results in terms of mass recovery and product quality.

Abstract Sampling campaigns were conducted at the industrial bauxite wash circuit of the Juruti Bauxite Mine in Pará, Brazil. The beneficiation circuit consisted of crushing, scrubber washing, wet screening, hydrocyclone classification, and fltration. Considering laboratory processing of samples and statistical analyses of historical operation databases, mass balances were obtained. Integrated analyses of historical databases, mass balances and operating parameters enabled the calculation of performance indices, which constitute the basis for the identification and hierarchy of the bottlenecks in terms of washability efficiency; that is, removal of the fraction below 0.037 mm. Typically, the focus of bauxite ore concentration in the Amazon region is the removal of the 0.037 mm fraction in the concentrate streams via disaggregation and mud washing. Consolidated mass balances indicated consistent values based on the size of the sample particles and percentage of solids, as well as the values obtained from the integrated information systems of the plant; this consistency indicated the stability and representativeness of the process conditions during the sampling campaigns. The base case of the Juruti plant operation, from which the performance indices that allowed the quantification of the efficiency of each process step was calculated, was obtained as a result.