It is known that ore containing cassiterite (SnO2) has been our most important source of tin since antiquity and its successful separation continuously pose problems to mineral processors. The situation is more pron...It is known that ore containing cassiterite (SnO2) has been our most important source of tin since antiquity and its successful separation continuously pose problems to mineral processors. The situation is more pronounced since the depletion of the more easily recoverable alluvial reserves forces us to work with the more complex deposits such as hardrock cassiterite ores. In order to understand more about the challenges in processing complex tin ore deposits, a metasedimentary rock ore sample from a mine in Malaysia was used in this study. Chemical analysis by wet method shows that SnO2 content in the sample was 2.86%, while for mineralogical analysis, the x-ray diffractogram (XRD) of the sample had identified that besides cassiterite, the sample also contained minerals such as quartz (SiO2) and clinochlore. Furthermore, the FESEM (field emission scanning electron microscope) micrograph analysis carried out on a polish section of the sample indicated that the fine cassiterite particles (approximately 80 ~tm) were found to be disseminated in the quartz minerals. Prior to the separation processes, grindability studies were carried-out on crushed samples to liberate the cassiterite from other gangue minerals and at the same time, avoid producing high percentage of fines. For the separation of tin from gangue minerals on the ground samples, two stages of gravity separations by shaking tables were carried out. The first stage was run on ground samples and for the second stage, the middling product from the first stage was re-tabled. Magnetic separation process on Concentrate 1 (stage 1) and Concentrate 2 (stage 2) products from the shaking table increased the grade of SnO2 to 46.85% and 61.90% respectively (as a non-magnetic products). Further concentration process of these non-magnetic products by high tension separator, increased the grade of SnO2 from 85.05% to 98.77%.展开更多
文摘It is known that ore containing cassiterite (SnO2) has been our most important source of tin since antiquity and its successful separation continuously pose problems to mineral processors. The situation is more pronounced since the depletion of the more easily recoverable alluvial reserves forces us to work with the more complex deposits such as hardrock cassiterite ores. In order to understand more about the challenges in processing complex tin ore deposits, a metasedimentary rock ore sample from a mine in Malaysia was used in this study. Chemical analysis by wet method shows that SnO2 content in the sample was 2.86%, while for mineralogical analysis, the x-ray diffractogram (XRD) of the sample had identified that besides cassiterite, the sample also contained minerals such as quartz (SiO2) and clinochlore. Furthermore, the FESEM (field emission scanning electron microscope) micrograph analysis carried out on a polish section of the sample indicated that the fine cassiterite particles (approximately 80 ~tm) were found to be disseminated in the quartz minerals. Prior to the separation processes, grindability studies were carried-out on crushed samples to liberate the cassiterite from other gangue minerals and at the same time, avoid producing high percentage of fines. For the separation of tin from gangue minerals on the ground samples, two stages of gravity separations by shaking tables were carried out. The first stage was run on ground samples and for the second stage, the middling product from the first stage was re-tabled. Magnetic separation process on Concentrate 1 (stage 1) and Concentrate 2 (stage 2) products from the shaking table increased the grade of SnO2 to 46.85% and 61.90% respectively (as a non-magnetic products). Further concentration process of these non-magnetic products by high tension separator, increased the grade of SnO2 from 85.05% to 98.77%.