Performance analysis of bauxite beneficiation process in Juruti Mine. Part 2: Simulation and optimization alternatives

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.摘要 本研究针对朱鲁蒂铝土矿（Juruti Bauxite Mine）的工业生产流程，采用适配设备参数的数学模型，并结合工业采样数据开展了模拟分析。本研究第一部分已对采样作业、物料衡算（mass balance）流程及流程效率量化方法进行了详细探讨，而模型校准与模拟流程则为第二部分的核心研究目标。模拟场景基于该选矿厂给料的潜在粒度曲线（particle size curves）设定。基于模拟结果，可明确哪些作业环节可能随产能提升受到波及，并进而影响最终产品中的杂质占比，由此表明需对相关设备进行改造以支撑产能扩张需求。另一组模拟场景则通过调整五级旋流器组（five cyclone stages）的底流口（apex）与溢流管（vortex finder）口径，旨在评估提升物料回收率及改善细粒产品质量的可行性。结合上述模拟场景，本次模拟识别出的重点关注事项包括：(a) 鉴于给入选矿厂的矿石特性发生变化导致停留时间缩短，洗涤效率或出现下降；(b) 需对一级及二级筛网进行扩容改造；(c) 为维持分级效率，需增设更多旋流器单元；(d) 调整底流口与溢流管口径可对物料回收率及产品质量产生影响。