Authors:Fatemeh Kazemi, Ataallah Bahrami, Yousef Ghorbani, Abolfazl Danesh, Morteza Abdollahi, Hadi Falah, Mohsen Salehi Pages: 1 - 12 Abstract: The interaction and synergic effect of particle size on flotation efficiency were investigated by a comparison study between laboratories (size-by-size flotation modes) and industrial scale operational data (whole mixed size fraction). For this purpose, sampling was done from the feed, concentrate, and tailing of the flotation rougher cells of the Sungun copper processing complex (located in the northwest of Iran). In the size-by-size flotation mode (lab scale), the sample was first subjected to different size fractions, and then flotation tests were performed for each fraction. On an industrial scale, the particle size distribution of feed, concentrate, and tailing of flotation of the rougher stage have been analyzed. According to the results, in the case of industrial flotation mode (whole mixed size fraction), the particles with d80=84 μm were more likely to reach the tailing of flotation, and the particles within the size range of +63-180 μm constituted the highest amount of concentrate particles. In lab flotation mode (size-by-size), the maximum recovery was in the size fraction of +40-60 μm. By comparing the two flotation modes of industrial (whole mixed size fraction) and lab (size-by-size), for fractions <45 μm, the industrial flotation recovery was approximately 40% greater than the lab flotation recovery. However, for fractions >125 μm, the recovery trend was reversed and the lab flotation recovery was greater than the industrial flotation recovery. Coarse particle flotation has significant economic and technological benefits. By improving the recovery of coarse particles during the flotation process, the amount of grinding requirements will be reduced and consequently, it will considerably decrease the amount of energy consumption. PubDate: 2023-03-06 DOI: 10.17794/rgn.2023.1.1 Issue No:Vol. 38, No. 1 (2023)
Authors:Rosmalia Dita Nugraheni, Widya Anggraini, Naily S. Setiawan, Cahyaningratri P. Riyandhani, Dewi Syavitri, Dedi Sunjaya, Agustinus Nopi, I Gde Sukadana Pages: 13 - 29 Abstract: The rising demand for scandium led to massive exploration activities for its discovery from mining by-products. Therefore, this study attempts to delineate the distribution of scandium-bearing minerals in the surrounding bauxite mining area, Tayan District, West Kalimantan Province, Indonesia. Preliminary studies were conducted by applying optical sensors to discriminate the types of minerals, such as kaolinite, gibbsite, goethite, and quartz. The spectral information aids the reconnaissance study by providing data on specific rocks and minerals using the short-wave infrared (SWIR), processed into a series of bands with spectral ranges from 0.35 to 2.5 μm. The data was then compared with the structural lineament from the ALOS PALSAR imagery to infer the prospective area with the structural pattern. The integrated band math minerals and geochemical data taken from X-ray fluorescence and Inductively Coupled Plasma-Mass Spectrometry suggest that the Sc-bearing minerals were disseminated predominantly on the bauxite laterite profile from pyroxene diorite and diorite parent rock weathering. The spectral range for goethite as the Sc-bearing minerals is from 0.43 to 1.03 , with the main absorption features from 2.0 to. 2.4 . Furthermore, goethite is mainly concentrated at the top bauxite horizon associated with the structurally related hill. The ore-bearing minerals also occupied the tailing pond and some beneficiation areas in relatively minor proportion. This study is undoubtedly valuable for the practical need to support mineral exploration through remote predictive mapping. PubDate: 2023-03-06 DOI: 10.17794/ rgn.2023.1.2 Issue No:Vol. 38, No. 1 (2023)
Authors:Putu Billy Suryanata, Satria Bijaksana, Mirzam Abdurrachman, Darharta Dahrin, Aditya Pratama, Nuresi Rantri Desi Wulan Ndari, Silvia Jannatul Fajar Pages: 31 - 40 Abstract: Geochemical and petrographic characterizations were carried out on five episodic effusive eruptions from Batur Volcano on the Island of Bali, Indonesia, and revealed that these lavas are basaltic to andesitic in composition. Various micro-textures were identified, reflecting pre-eruptive magmatic processes, magma mixing, and adiabatic decompression. Apart from XRF analyses, the five lava flows (L849, L926, L963, L968 and L974) were subjected to magnetic analyses in the form of magnetic susceptibility and magnetic hysteresis measurements. The presence of cyclicity in the magmatic process is suggested by the variation of micro-texture types, CaO content, and magnetic susceptibility values. Two possible models of this cyclicity are presented. In the first model, cyclicity is driven by the variation of influx from the lower magma chamber that affects the interaction of magma with the surrounding rocks. In the second model, cyclicity is affected by the appearance of a new magmatic vent, which causes intense interaction with surrounding rocks. This study infers that combined micro-texture, composition, and magnetic susceptibility analyses might provide insight into the cyclicity of lava episodes observed in active volcanos such as Batur. PubDate: 2023-03-06 DOI: 10.17794/rgn.2023.1.3 Issue No:Vol. 38, No. 1 (2023)
Authors:Ahmed M. Shohda, Waleed M. Draz, Faisal A. Ali, Mohamed A. Yassien, Mahrous Ali Mohamed Ali Pages: 41 - 48 Abstract: The nature of ornamental stones is anisotropic. The heterogeneous characteristics of the anisotropic rocks vary with direction. The highest to lowest strength ratio is known as the anisotropy strength index (ASI). A thorough investigation of the ASI is necessary to determine the best-directed loads for these rocks. On core specimens that have been bored parallel and perpendicular to the weakness planes, this is estimated using both uniaxial compression and point load testing. For this examination, four different rock types had cores that were drilled conventionally and in line with weakness planes. The research shows that drilling cores to weakness planes at a normal or nearly normal angle (90° to 60°) yields the best, most dependable ASI. According to the current study's findings, the ASI fluctuates depending on how uniformly the mineral content and texture of rocks are. A suggested way to calculate the ASI and the load point strength is also included. This study reveals that the employment of ornamental stone as is (for example, precipitation position is more robust and reliable than that perpendicular form) is critical in determining the resilience of this type of rock and its spatial implementation (e.g. flooring). PubDate: 2023-03-06 DOI: 10.17794/rgn.2023.1.4 Issue No:Vol. 38, No. 1 (2023)
Authors:Ana Getaldić, Marija Surić Mihić, Galla Uroić, Želimir Veinović Pages: 49 - 58 Abstract: Having access to relevant data is essential for ensuring the quality and outreach of research work. In the context of the nuclear field, access to information and data facilitates competence building, long-term professional development, research, and information dissemination. Potential users of nuclear information resources come from different domains: scientists, experts, students, and the public. One of the main roles of the International Atomic Energy Agency (IAEA) is to ensure and promote peaceful uses of atomic energy worldwide. Through their activities, the IAEA strongly encourages the exchange of scientific and technical information. This paper presents an overview of different nuclear and radiological data available in several International Atomic Energy Agency databases. All data is available free of charge for educational and informational use. A summary of information is given for each database presented on the content, access options, copyright, acknowledgement, and dissemination of the available information. A concise summary of this various data might help in capacity building, as well as encourage research and information sharing between different stakeholders in the field. PubDate: 2023-03-06 DOI: 10.17794/rgn.2023.1.5 Issue No:Vol. 38, No. 1 (2023)
Authors:Hassan Maleki, Mohammad Noparast, Sajjad Chehreghani, Mir Saleh Mirmohammadi, Ali Rezaei Pages: 59 - 68 Abstract: One of the main challenges in the copper oxide processing industry is the application of flotation to reduce operating costs. Sulfidation-flotation is a commonly employed approach for floating oxide minerals using sulfidizers in order to sulfide the mineral’s surface. In this research work, an oxidized sample from the Qaleh Zari copper mine was used which was a high grade with 5.4% of copper (malachite and azurite). The prepared sample was subjected to mineralogical studies, and the obtained results indicated that the sample was oxidized. Malachite and azurite were the predominant minerals of copper oxide, and the predominant waste minerals were quartz and iron oxides (hematite and magnetite). The addition of sodium sulfide and flotation in four consecutive steps was a successful approach to meet the proper recovery and grade. Sodium sulfide, amyl potassium xanthate, sodium sulfide preparation time, and pH were selected as operating parameters using a central composite design (CCD). Also, by measuring the zeta potential, the electric charge of malachite was determined in different conditions after adding chemicals. Finally, under optimal conditions, the consumptions of sodium sulfide and amyl potassium xanthate, sodium sulfide preparation time, and pH value were 6790 g/t, 736 g/t, 10 minutes, and 9, respectively. By applying the mentioned conditions, a concentrate with a grade of 22.13%Cu and 90.51% recovery was achieved. PubDate: 2023-03-06 DOI: 10.17794/rgn.2023.1.6 Issue No:Vol. 38, No. 1 (2023)
Authors:Hojjat Hosseinzadeh Gharehgheshlagh, Sajjad Chehreghani, Behnam Seyyedi Pages: 69 - 82 Abstract: Grinding aids are materials that are added to cement mixtures to improve the characteristics of the cement or increase the efficiency of the milling systems or both in the clinker grinding (finish grinding) stage. In this study, the effects of four grinding aids (Triisopropanolamine based (TIPA), Triethanolamine based (TEA), Hydroxylamine based (HA), and Calcium nitrate based (CN) grinding aids) in the clinker grinding process were evaluated on the essential characteristics of the produced cement: namely specific surface area (Blaine number), compressive strength of concrete, and the comminution efficiency-retention time (energy saving) at four different dosage levels. In the first step, the grinding time required to reach the Blaine number of the investigated Cement type (S-OPC: Studied Ordinary Portland Cement) was obtained as 69.75 minutes by kinetic grinding tests. Afterward, 17 laboratory-scale grinding tests were performed utilizing S-OPC cement and four grinding aids at four different doses of 0.02%, 0.05%, 0.08% and 0.11 %. The results indicated that the TIPA-0.11 (Triisopropylamine compound at a dosage level of 0.11%), with a Blaine value of 4069 cm2/g, and grinding efficiency of 19%, had the most significant effect on the fineness and comminution efficiency. Furthermore, the concrete samples produced from all the grinding aids were tested for their compressive strength at 2, 7, and 28 days. The results showed that compared to control samples, the highest growth of compressive strength were on day 2 and 7 for TIPA-0.11 samples with values of 37.08% and 32.44%, respectively. Meanwhile, the highest increase of compressive strength was after 28 days for TIPA-0.11 samples with a 22.14% increase. PubDate: 2023-03-06 DOI: 10.17794/rgn.2023.1.7 Issue No:Vol. 38, No. 1 (2023)
Authors:Vjekoslav Herceg, Mario Klanfar, Karolina Herceg, Dubravko Domitrović Pages: 83 - 92 Abstract: A hydraulic excavator is widely used in crushed stone quarries to perform many different operations. Previous research on material handling by excavators is most often based on laboratory testing and observation of soil materials and the digging forces in them. These results are very difficult to transfer to fieldwork during the quarrying process. Therefore, in this work, the energy consumption of an excavator while working in typical materials for a crushed stone quarry was investigated. The field measurements were performed on overburden, blasted rock material, boulders, and two different crushed materials. Energy consumption was observed only during the portion of the cycle in which the bucket digs the material. In this way, the energy consumption was mainly related to the properties of the material. The highest energy consumption was found for blasted rock material, lower in overburden, and the lowest for boulders and crushed materials. These results are important for organizing an optimal distribution of machines according to the work tasks in the quarry and ultimately for energy savings. PubDate: 2023-03-06 DOI: 10.17794/rgn.2023.1.8 Issue No:Vol. 38, No. 1 (2023)
Authors:Seyed Ahmad Mousavi, Kaveh Ahangari, Kamran Goshtasbi Pages: 93 - 104 Abstract: The process of creating a slope in a rock mass using the excavation and blasting methods consistently leads to stress release in the rock mass, resulting in a certain level of fracture and disturbance. Blast-induced vibrations can also influence the quality of the rock mass remaining after the blasting, as well as the stability and bench damage monitoring (BDM) of mines. A damage factor (D) is included in the Hoek–Brown failure criterion to compute the disturbance of a rock mass in creating a slope. Choosing the value and thickness of the blast zone for the Hoek–Brown criterion is crucial in the safety analysis and BDM of mines. However, the selection is still a crucial technical challenge in this criterion. Employing nonlinear layering, the present study divides the rock mass behind a blast hole into several layers with decreasing D values applied to each layer. The numerical simulation was conducted using the FLAC finite difference software for bench vibration assessment and damage monitoring by checking the peak particle velocity (PPV) in the bench face with different geometries. Behind the blast hole, five different layers of D were considered through which the Hoek–Brown properties of the rock mass declined nonlinearly during the execution of the model. Since the disturbance threshold of PPV was assumed to be 120 mm/s, the toe and middle parts of the small benches were in the disturbance threshold, while for the medium and high benches, only the bench toe was within the disturbance threshold. PubDate: 2023-03-06 DOI: 10.17794/rgn.2023.1.9 Issue No:Vol. 38, No. 1 (2023)
Authors:Seyyed-Omid Gilani, Sayfoddin Moosazadeh, Rashed Poormirzaee Pages: 105 - 117 Abstract: An essential task in the open-pit mine optimizing process is determining the extraction time of material located in the ultimate pit, considering some operational and economic constraints. The proper design of pushbacks has a significant impact on the optimum production planning. On the other hand, some uncertainty sources such as in-situ grade cause both deviations from production and financial goals. This paper presents an extension of a multi-stage formulation for risk-based pushback designing that utilizes the ant colony optimization (ACO) algorithm to solve it. For more detailed studies, two different strategies were developed according to statistical and probabilistic issues. The data of Songun copper mine located in NW Iran was used to evaluate the ability of the proposed approach in controlling the risk of deviation from production targets and increasing the project value. The results indicated the effectiveness of the proposed approach in pushback designing based on geological uncertainty. Examining different strategies showed that the technique based on multiple probability produces better solutions. PubDate: 2023-03-06 DOI: 10.17794/rgn.2023.1.10 Issue No:Vol. 38, No. 1 (2023)
Authors:Želimir Veinović, Helena Vučenović, Ivana Rožman, Galla Uroić Pages: 119 - 136 Abstract: Given the forthcoming need for the construction of a repository for low and intermediate radioactive level waste in the Republic of Croatia, this paper proposes a repository design which is, from a geotechnical point of view, simple, practical and safe, and significantly improved considering current conceptual designs. Existing low and intermediate radioactive level waste repositories are mostly vault-type, near-surface constructions with some kind of covering (top) system of protective layers. However, most of these repositories do not have a bottom protective system, apart from concrete flooring (base). The reasons for such designs include the presumed longevity of the waste packages (containers), which are mostly reinforced concrete and/or steel containers. Considering that the concrete is a material which will, under certain conditions, deteriorate (e.g. dissolution of the cement matrix), and so potentially release radionuclides to the environment, it is essential to design the repository in such a manner that all forms of early release of radionuclides are prevented. The improved conceptual design of low and intermediate radioactive level waste repository presented in this paper is intended to provide an improved containment of radionuclides from waste and ensure the long term safety of the repository. This paper is the first in a series which will cover the basic design of the repository, systems of protective layers and preliminary slope stability analyses. PubDate: 2023-03-06 DOI: 10.17794/rgn.2023.1.11 Issue No:Vol. 38, No. 1 (2023)
Authors:Gabrijela Ljubek, Marijana Kraljić Roković Pages: 137 - 148 Abstract: The aim of this work was to determine the optimal synthesis conditions for the preparation of a poly(3,4-ethylenedioxythiophene) (PEDOT) layer by the electrochemical method from an electrolyte containing graphene oxide (GO) and a sodium dodecylsulfate (SDS) micellar solution. Besides an SDS anion, GO is also incorporated within the PEDOT layer as a negative counter ion. Therefore, this is a one-step electrochemical method for a PEDOT/GO composite layer preparation. The results displayed that PEDOT composites were successfully synthesised by applying a potential in the value range from 0.94 to 1.00 V, and with a synthesis duration of up to 600 s. It was concluded that the optimal concentration of EDOT monomer is 0.02 mol dm-3, and SDS 0.01 mol dm-3. The incorporation of GO into the PEDOT layer improved the polymer response in KCl solution influencing the pseudocapacitive properties, which is significant for its supercapacitor applications. The morphological and structural properties of the obtained layers were characterized by means of scanning electron microscopy and ultraviolet-visible spectrophotometry. The pseudocapacitive properties were determined in a 0.1 mol dm-3 KCl solution by using cyclic voltammetry and electrochemical impedance spectroscopy methods. PubDate: 2023-03-06 DOI: 10.17794/rgn.2023.1.12 Issue No:Vol. 38, No. 1 (2023)
Authors:Jenny Marina Vásquez Acuña, Miguel Estrada Mendoza Pages: 149 - 166 Abstract: It has been long observed that the Peruvian Central Highway (PE-22) and the LM-116 road are among the roads most affected by mass movements (MM) in Peru, frequently exposed to the occurrence of rockfalls, debris flow and landslides; both roads represent an important connection alternative between Lima with towns, cities and mining centers located in the Central Mountain Range of the Andes. In this research, firstly, a point density analysis was performed using Geographic Information Systems (GIS) considering the road network of all of Peru (composed of 144,499 km) and the inventory of geological hazards (GEOCATMIN) prepared by the Geological, Mining and Metallurgical Institute of Peru INGEMMET (2000-2018). Subsequently, the evaluation of the mass movement susceptibility on the LM-116 road has been carried out using free access data reported by Peruvian institutions (INGEMMET, MTC, MINAM) from which it was possible to elaborate thematic maps, including the most relevant factors in the occurrence of mass movements, like a slope, lithology, geomorphology, land use, drainage density, and the distance from tectonic structures. Finally, for the mass movement susceptibility analysis, three methods have been considered: the Analytic Hierarchical Process (AHP), the Statistical Index (Wi) and the Weights of Evidence (WoE). The results were validated using the area under the curve criteria (AUC). Both bivariate statistical methods (Wi and WoE) presented a prediction rate above 78%, with a higher rate for the WoE method. On the other hand, the semi-quantitative method (AHP) obtained values in the order of 69%. Therefore, it is concluded that the maps elaborated with the statistical methods presented a better approximation concerning the database of geological hazards reported by GEOCATMIN. PubDate: 2023-03-06 DOI: 10.17794/rgn.2023.1.13 Issue No:Vol. 38, No. 1 (2023)
Authors:Ryan Dwi Wahyu Ardi, Aswan, Khoiril Anwar Maryunani, Eko Yulianto, Purna Sulastya Putra, Septriono Hari Nugroho Pages: 167 - 178 Abstract: Despite its importance, sea surface paleoproductivity of the western Savu Strait is not well studied. Results from previous studies at the nearby Southwest Sumba and Sumba Strait might not be applicable due to the oceanographic difference. Foraminiferal proxies from gravity core ST10 were applied to generate sea surface paleoproductivity and thermocline depth reconstruction. Foraminiferal Accumulation Rate and Benthic Foraminiferal Accumulation Rate were used as paleoproductivity proxies while the thermocline dwellers’ relative abundance was applied as the thermocline depth proxy. This study suggested paleoproductivity increase during the Last Glacial Maximum (LGM)–~16 ka BP and Holocene (after ~11.65 ka BP) in the western Savu Strait. Thermocline depth was relatively shallower during the LGM–Last Deglaciation and became deeper afterwards. Paleoproductivity increase at LGM–~16 ka BP was caused by the Australian-Indonesian winter monsoon (AIWM)-like condition, characterized by intense coastal upwelling while the Holocene paleoproductivity increase was related to the abrupt rainfall increase which enhanced terrestrial/riverine input. Thermocline depth variability in the western Savu Strait is in-phase with thermocline depth variability in the Java upwelling region, characterized by a shallower thermocline during the LGM–Last Deglaciation (before ~11.65 ka BP) and a deeper thermocline during the Holocene (after ~11.65 ka BP). This thermocline depth shifting indicates a strong Australian-Indonesian Monsoon (AIM) influence on the paleoceanography of the western Savu Strait since LGM. PubDate: 2023-03-06 DOI: 10.17794/rgn.2023.1.14 Issue No:Vol. 38, No. 1 (2023)
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