Scientific Mining Journal

Scientific Mining Journal

Volume 57 - No 4 (December 2018)
The Effect of Grinding Aids on Wet Grinding of Muscovite in a Stirred Ball Mill ( Original Research )
DOI 10.30797/madencilik.479902 Serkan Çayırlı, Hasan Serkan Gökçen, Volkan Bozkurt, Yaşar Uçbaş
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ABSTRACT

In this study, the effects of grinding aids (sodium hexametaphosphate and polyacrylic acid sodium salt) on the wet grinding of muscovite to micronized size (d50: 15 μm) in stirred ball mill were investigated. The results were evaluated based upon the specific energy consumption (kWh/t) and flow characteristics of the products. Experimental results showed that 10.4% of energy savings can be obtained by using of 4000 g/t sodium hexametaphosphate and 9.9% of energy savings can be obtained by using of 1000 g/t of polyacrylic acid sodium salt. It was also found that the grinding aids reduced the shear stress and viscosity values of the pulp without changing the flow type. It was concluded that reduction in flow parameters of the pulp resulted in energy saving.

Effects of Solvents and Oxidants on Metal Recovery from E-Wastes ( Original Research )
DOI 10.30797/madencilik.480060 Ayşenur Tuncuk
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ABSTRACT

The study presents the process of leaching waste central processing units (CPU) to recover copper, gold and silver by using alternative solvents. Physical pre-treatments (size reduction, dismantling) followed by hydrometallurgical methods were used to achieve metals recovery with high efficiencies. 23 full factorial design tests were conducted in chemical leaching tests. The effects of reagent (I2, H2SO4, NH3) concentration, oxidant (H2O2, (NH4)2S2O8) concentration, solid/ liquid ratio on the metal recovery yield were studied by analysis of variance (ANOVA), models related to the effective values were created. In order to improve the metal recovery, two-step reactor leaching tests were conducted. 95.60% copper recovery was obtained in the first step with H2SO4+H2O2 leaching, 99.92% gold and 99.81% silver recoveries were obtained in the second step with I2+H2O2 leaching.

The Developed Methods for Stope Boundary Optimisation and A Relevant Case-Study ( Original Research )
DOI 10.30797/madencilik.480083 Gamze Erdoğan Erten, Mahmut Yavuz
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ABSTRACT

The stope boundary optimisation which could be considered as a starting point for the underground planning and design optimisation process focuses on maximizing the economic profit by selecting the best possible stope layout by considering operational, geotechnical and physical constraints. Although the numerous algorithms and techniques have been developed for this area, which has received attention for the last 20-25 years, they have been far behind the studies of open pit mining. This article first analyses the literature on the methods developed for the stope boundary optimization in detail, and then demonstrates the implementation of a selected algorithm on an actual ore body model. Results show that none of the methods developed for the stope boundary optimization up to now have could yet guaranteed the exact optimum results in three dimensions (3D) and most of them remained as a heuristic method.

Investigation of Gasification Characteristics of Ilgın Coals by Thermogravimetric Analysis Method ( Original Research )
DOI 10.30797/madencilik.479523 İbrahim Çınar, Mustafa Altun
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ABSTRACT

Coal formation has a heterogeneous structure. Therefore, there are many factors affecting the coal gasification. Thermal analysis in determining the properties of the coal gasification and the effects on characteristics of the coal gasification these factors is one of the best procedure for the evaluation. In this study, the transformation times and gasification rates of the samples taken from the Ilgın coal were determined by thermogravimetric analysis and the effects of temperature on these factors were investigated. Conversion time and gasification rates of Ilgın coals were investigated using thermogravimetric analyzer at 700°C, 750°C, 800°C and 850°C in CO2 atmosphere and comparisons were made between samples. It was observed that the conversion time of the Ilgın coal at 800°C was shorter than the other temperatures.

Experimental Design of Ree Extraction From Isparta Çanaklı Ore with Sulphuric Acid Leaching ( Original Research )
DOI 10.30797/madencilik.479527 İlgin Kurşun, Mert Terzi
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ABSTRACT

In this study, rare earth element (REE) dissolution efficiencies from Isparta Çanaklı REE containing weathered pyroclastic ore at different leaching conditions in the sulfuric acid medium were investigated. In the experimental studies, 2n factorial design and Yates experimental layout technique were used. Acid concentration, leaching time and pulp temperature were chosen as the main variables. The best results were obtained under the conditions of 5M H2SO4, 5 hours leaching time and 100oC pulp temperature and the dissolution rates of total REE (TREE), light REE (LREE), heavy REE (HREE), Ce, La and Nd were obtained as 65.34%, 61.80%, 65.22% 66.09%, 66.86% and 68.38%, respectively. Models were created using Minitab software using effective parameters determined by ANOVA analysis, and correlation analyses were performed between experimental and theoretical results. The correlation coefficient (R2) between the experimental and theoretical results for the TREE, LREE, HREE, Ce, La and Nd dissolution efficiencies were calculated as 0.7933, 0.7721, 0.9323, 0.6700, 0.8312 and 0.8183, respectively.

Micro-Analytical Methods Used in Characterization of Gold Ores ( Review )
DOI 10.30797/madencilik.479520 Oktay Celep, Ahmet Deniz Baş, Ersin Yener Yazıcı, Hacı Deveci
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