STUDY OF THE EFFECTS OF PERCENT SOLIDS, PH, AND VISCOSITY MODIFIER REAGENT ON WET GRINDING PRODUCTS OF OXIDE TYPE PRIMARY TIN ORE FROM BATUBESI, BELITUNG

• Main Author: Nuriyansyah, Rizki
• Format: Final Project
• Language: Indonesia
• Online Access: https://digilib.itb.ac.id/gdl/view/80486
• Institution: Institut Teknologi Bandung

Secondary or placer tin deposits still contribute to around 70% of global tin production, which continues to dominate global tin exploration. Thus, exploration activities for primary tin deposits increase to fulfill tin demand throughout the world. Belitung especially Batubesi area is one of the many locations in Indonesia that has abundant primary tin ore resources, one of them is oxide skarn type. In the mineral processing, grinding is a crucial stage in the size reduction and liberation of minerals. Optimization of mill throughput in wet grinding operations can be improved by increasing percent solids of the slurry. Solids concentration has a significant impact on slurry viscosity. The results of this study will aid in selection of solid content of the pulp to further optimize grinding performance. Floperse 1000 (PAA) as grinding aids were added to the mill charge in small percentages to improve the rheological behaviour and the performance of the mill. The effect of slurry pH on Flosperse 1000 performance was then explored together with the resulting breakage process. Tin ore were initially prepared by several treatments: drying at ???????????????? for 3 days, sieve analysis, crushing for oversize ore that is greater than 3# in size, desliming, ore homogenization, sampling, mineralogical characterization through x-ray diffraction (XRD), and trace element detection through x-ray fluorescence (XRF). Four levels of slurry solid content were considered at 50%, 60%, 75%, and 85%. In the next step, pH of slurry was fixed at 6, 8, and 10 while other parameters were kept constant, such as solid content at 75% and Flosperse 1000 dosage at 400 gpt. Grinding tests were carried out for multiple durations consisting of 2, 5, 10, 15, 20, 30, 40, 60, and 80 minutes. The ball mill was rotated on a roller at 81,96 rpm, or 80% of critical speed. The rheological measurements of mill product were performed with the Brookfield D-III rheometer. Sieving was used for determining particle size distribution (PSD) of the slurries obtained after grinding the ore. The effects of the grinding environment of oxide type primary tin ore were investigated. Variation in grinding time between 2 and 80 minutes showed that increasing grinding time decreased mill product P80 and increased viscosity. Increasing in solid content results in coarser grind and thicker pulp. At the current stage, Flosperse 1000 as polymeric dispersants are found effective with respect to reducing pulp viscosity and P80. The pH of slurry was changed from 6 to 10 and improves dispersing agent performance.