STUDY OF REGRIND CIRCUIT SIMULATION AT PT. NEWMONT NUSA TENGGARA CONCENTRATOR USING JKSimMet

• Main Author: PRASETIAWAN (NIM 12103015), ANGGA
• Format: Final Project
• Language: Indonesia
• Online Access: https://digilib.itb.ac.id/gdl/view/9942
• Institution: Institut Teknologi Bandung

<p align="justify">The losing of valuable metals in current cleaner flotation circuit at PT. Newmont Nusa Tenggara concentrator is known mainly in very fine (-8 micron) fraction. In this size fraction, valuable metals are not floated in the flotation process and become final tails. In order to reduce the losses, one of the ways is by regrind circuit optimisation in which the product of this circuit is one of feed for cleaner circuit. Optimisation, particularly in comminution closed circuit involving classifying operation is a complicated task. For example, changing the solids split to meet a classification or separation efficiency target will generally affect the water split too. The performance of the classifying device, or cyclone, will also strongly affect the comminution process. So that, in order to optimise the circuit efficiently without interrupt the circuit operation, simulation is the best choice to be implemented as long as the model used in the simulation is reasonably accurate enough under prevailing conditions.<p align="justify"><p>In this study, the size reduction and classification in the regrind circuit will be modeled and simulated using JKSimMet to obtain the best setting of operational condition. The variables used and studied in this simulation were quantified cyclone dimension (vortex finder-apex, apex, vortex finder, cyclone number), unquantified cyclone dimension (inlet diameter, cylinder height, cylinder diameter, cone angle), and circuit condition (percent solids of cone settler underflow, water addition in cylone and tower mill respectively). Before the simulation, a series of experiment which include sampling, splitting, wet screening, and dry screening of the samples around the circuit have to be performed. The results of this experiment will be used as one of the input data for modeling and simulation.<p align="justify"><p> The results of simulation and analysis showed that the most optimum circuit condition (the biggest reducing of very fine (-8 micron) fraction in the overflow product) was by operating three paralel cyclone and changing current vortex finder of the cyclone (0.152 m in size) with the one of 0.171 m in size.