Research Article
Effect of Particle Size and Splitter Opening on Ilmenite Separation Using an Induced Roll Magnetic Separator
Taufik Arief
,
Dela Citra*
Issue:
Volume 11, Issue 4, December 2026
Pages:
75-84
Received:
3 September 2026
Accepted:
17 September 2026
Published:
14 October 2026
Abstract: Ilmenite (FeTiO₃) is an economically valuable associated mineral in tin deposits and an important source of titanium. Its recovery from tin-processing tailings can increase the utilization value of mineral resources. This study evaluated the effects of particle size and splitter opening on ilmenite grade and recovery using an Induced Roll Magnetic Separator (IRMS). The experiment used air-table tailings from PT Timah Tbk. The feed was classified into three particle-size fractions, namely −50# +80# (177–300 µm), −80# +100# (149–177 µm), and −100# (<149 µm), and processed at splitter openings of 100%, 60%, and 20%. Feed characterization was performed using X-Ray Fluorescence (XRF) and Grain Counting Analysis (GCA). Each treatment combination was tested twice. The experimental results showed that ilmenite grade increased after magnetic separation for all particle-size fractions. The highest grade of 85.92% was obtained from the −80# +100# fraction at a 20% splitter opening, whereas the highest recovery of 59.19% was obtained from the −50# +80# fraction at a 100% splitter opening. Two-Way ANOVA showed that particle size, splitter opening, and their interaction significantly affected both grade and recovery (p < 0.05). Particle size was the dominant factor for grade, while splitter opening had the greater effect on recovery. Quadratic regression of particle size against ilmenite grade produced R2 = 0.953 and an optimum coded particle size of 1.687, corresponding more closely to the −80# +100# fraction. The results demonstrate that particle size and splitter opening should be considered simultaneously in optimizing ilmenite separation using IRMS.
Abstract: Ilmenite (FeTiO₃) is an economically valuable associated mineral in tin deposits and an important source of titanium. Its recovery from tin-processing tailings can increase the utilization value of mineral resources. This study evaluated the effects of particle size and splitter opening on ilmenite grade and recovery using an Induced Roll Magnetic ...
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Research Article
Effect of Grinding Fineness on Concentrate Grade and Metal Recovery in Copper-molybdenum Ore Beneficiation
Issue:
Volume 11, Issue 4, December 2026
Pages:
85-92
Received:
8 October 2026
Accepted:
17 October 2026
Published:
26 October 2026
Abstract: This study examines the influence of grinding fineness on concentrate grade, product yield, and copper, molybdenum, and gold recovery during flotation beneficiation of copper-molybdenum ore from the Kalmakyr deposit. Five grinding conditions were compared, corresponding to 57%, 60%, 65%, 70%, and 80% by mass passing 0.074 mm. The evaluation was based on the reported assays, yields, and recoveries of flotation products under the investigated flowsheet. Increasing the proportion of material passing 0.074 mm from 57% to 70% raised copper recovery from 83.79% to 88.73%. At 70% passing 0.074 mm, the combined concentrate yield was 7.76%, with grades of 3.82% Cu, 0.039% Mo, and 5.02 g/t Au; corresponding recoveries were 88.73% Cu, 82.61% Mo, and 77.80% Au. At 80% passing 0.074 mm, copper, molybdenum, and gold recoveries increased further to 89.01%, 83.14%, and 79.67%, respectively, while the combined concentrate yield was 7.72%. Thus, the finer grinding condition delivered the highest reported recoveries, whereas the 70% condition provided a slightly coarser alternative with recoveries close to those obtained at 80%. Without grinding-energy or operating-cost measurements, an economic optimum cannot be demonstrated from these data alone. The manuscript also discusses staged addition of spindle oil, regrinding, and the possible inclusion of centrifugal gravity concentration. These process modifications are distinguished from the grinding-fineness comparison and should not be interpreted as verified improvements without matched experimental controls. The findings provide an experimental basis for comparing practical grinding targets for the investigated ore and identify the additional measurements required before final process optimization.
Abstract: This study examines the influence of grinding fineness on concentrate grade, product yield, and copper, molybdenum, and gold recovery during flotation beneficiation of copper-molybdenum ore from the Kalmakyr deposit. Five grinding conditions were compared, corresponding to 57%, 60%, 65%, 70%, and 80% by mass passing 0.074 mm. The evaluation was bas...
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Research Article
The Flotation Response of Dedo Coal Deposit, Jimma, Ethiopia: Implication to Improve the Quality of Coal
Dejene Amane*,
Melesse Alemayehu
Issue:
Volume 11, Issue 4, December 2026
Pages:
93-101
Received:
25 September 2026
Accepted:
13 October 2026
Published:
29 October 2026
Abstract: Ethiopia possesses considerable coal resources, but their low grade, marked by high ash and moisture, restricts industrial utilization. This work examined how run-of-mine coal from the Dedo deposit in Jimma Zone, south-western Ethiopia, responds to froth flotation, with the goal of raising its quality. Duplicate batch tests were run in a laboratory Wedag flotation cell to assess how particle size (−500+250 µm and −125+63 µm) and impeller speed (1500 and 2500 rpm) influence concentrate yield. Kerosene served as the collector and n-octanol as the frother, and the feed mass, conditioning time and reagent dosages were kept fixed. Proximate analysis, sulfur content and calorific value were used to characterize both the raw coal and the floated concentrate. Mean concentrate yield varied from 48.0% for the coarse fraction at 1500 rpm up to 66.5% for the fine fraction at 2500 rpm, which shows that, within the ranges tested, finer particles and a higher impeller speed improved flotation. Compared with the raw coal, the concentrate produced under the best conditions contained less ash (25.66% to 20.28%), moisture (13.63% to 11.06%), volatile matter (33.45% to 25.63%) and sulfur (0.36% to 0.25%), and had a higher calorific value (4806 to 5029.38 cal/g), while fixed carbon increased (27.26% to 43.03%). The findings suggest that froth flotation can give a cleaner, more energy-rich product from Dedo coal; however, the calorific value gain was small (about 4.6%), and only two levels of two variables were investigated. Before process conditions for industrial use can be defined, the effects of collector and frother dosage, solids concentration, pH, air flow rate and conditioning time, as well as the composition of the flotation tailings, still need to be assessed.
Abstract: Ethiopia possesses considerable coal resources, but their low grade, marked by high ash and moisture, restricts industrial utilization. This work examined how run-of-mine coal from the Dedo deposit in Jimma Zone, south-western Ethiopia, responds to froth flotation, with the goal of raising its quality. Duplicate batch tests were run in a laboratory...
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