STUDY OF OPEN PIT TIN MINE DESIGN OPTIMIZATION PT XYZ, BANGKA BELITUNG PROVINCE

• Main Author: Pauli Siahaan, Florencia
• Format: Final Project
• Language: Indonesia
• Online Access: https://digilib.itb.ac.id/gdl/view/43996
• Institution: Institut Teknologi Bandung

PT XYZ is one of tin mining company in Indonesia which has been already operating several open pit mines. PT XYZ has a pit that has been mined and still has remaining reserves, therefore pit optimization needs to be carried out to maximize the mining recoveries. However, the location of the pit is close to the residential pathway, so in the process of optimizing this pit, it is necessary to consider the residential pathway as restricted area parameter. PT XYZ also wants to know the effect of fluctuation in tin selling price and the operating costs to the number of reserves that can be mined. Ultimate pit limit determination is carried out by Whittle software that refers to the Lerchs-Grossmann Algorithm pit optimization method. From the pit optimization results, ore tonnage values, stripping ratio, tin grade, and the optimal block model to be mined are obtained. A pit design is made based on the pit optimization results that have been obtained by considering non-technical parameters, which is the restricted area boundaries. As consequences, the ultimate pit limit design on Datamine cannot completely follow the shape of the block model produced by Whittle. Furthermore, the simulation of fluctuation in tin selling price and operating costs is carried out with the same steps, by changing the input parameters on Whittle and making designs with Datamine based on the optimized block models. From the pit design optimization results, the optimal ore tonnage to be mined is 8,555,812 tons of the total 9,014,867 tons of available resources, with an average grade of 0.5% and a stripping ratio of 7.4. From the simulation results of fluctuation in the tin selling price and operating costs, it is found that the two parameters do not significantly affect the number of reserves that could be mined.