Journal of Mining World Express
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Open Access journal
ISSN (Print) 2169-642X - ISSN (Online) 2169-6438
Published by Science and Engineering Publishing Company [49 journals]
- Investigation of Physical and Mechanical Properties of Selected Rock Types
in Kogi State Using Hardness Tests
Abstract: Investigation of Physical and Mechanical Properties of Selected Rock Types in Kogi State Using Hardness Tests
Author Godwin AnikohPatrick Adeniyi AdesidaOluwasanmi Cosmas Afolab
The research investigated the physicomechanical properties of selected granite and limestone in Kogi State, Nigeria. The objectives of the research were achieved through samples collection and analyses. The rock samples were collected for the determination of the physicomechanical properties and the hardness properties of the rocks in the laboratory. The results obtained reveal that the mean densities of selected granite and limestone are 2.61 g/cm3 and 2.67 g/cm3 respectively while their respective porosities are 1.35 % and 2.79 %. The respective main uniaxial compressive strength, point load strength and tensile strength of the selected granite and limestone are 168.92 MPa, 112.17 MPa, 6.83 MPa, 4.34 MPa, 10.24 MPa and 6.51 MPa. The determined properties were subjected to statistical analysis using SPSS of model IBM SPSS Statistics 21. The determined physicomechanical properties are the dependent variables while the hardness properties are the independent variables. The mathematical models were generated from the analysis. The generated models can be a useful tool in determining the physicomechanical properties of the tested rocks.
- Microbiological Beneficiation of Low Grade Manganese Ores: A Review
Abstract: Microbiological Beneficiation of Low Grade Manganese Ores: A Review
Author Jai S. GhoshArvind D. Agat
Manganese is a transition element like iron. However, it exists in different valencies like 2, 3, 4 and 7. Of these, Mn2+ is highly water soluble, but is rarely found in natural conditions. Mn4+ is the least water soluble and under different pH and redox conditions it can slowly become colloidal in natural water. It exists naturally as a very common mineral called pyrolusite and is used for pyrometallurgical processes in ferro-alloys industries. However, in order to have such beneficial application, the manganese content should be more than 80% in the ore. Anything less than this is treated as low grade ore and is usually dumped on land with cultivable soil, in order to reach deeper for the high grade ores. This is highly ecotoxic to the environment and over a period of time can be very damaging to agriculture and the biodiversity which includes human health as it finds its way to ground water table like wells and ponds. As time went by and high grade ore started depleting, miners started going deeper in the ground, with the result of dumping lower grade ores over surface soils. In this study, such low grade ores were examined and found to contain a mixture of Mn3+ and Mn4+ oxides. When such ores were subjected to microbial oxidation, it was found that under certain conditions of growth, Arthrobacter sp could not only convert the Mn3+ to Mn4+ and 67% of the Mn4+ oxides had the ramsdellite γ- crystalline structure, which could be used as a depolarizer in the dry cell batteries. This was considered as a very important biotechnological discovery which not only could save the biodiverse environment but also gave a value added product for commercial exploitation.
- Evaluation of Suitability of Some Selected Rocks for Dimension Stone
Quarry in Akure, Ondo State, Nigeria
Abstract: Evaluation of Suitability of Some Selected Rocks for Dimension Stone Quarry in Akure, Ondo State, Nigeria
Author Afeni Thomas BusuyiMoshood OnifadeOmotayo Bolaji Raphae
The evaluation ofrock suitability for dimension stone quarry has been a thing of concern to the dimension stone industries. So, three granite rocks were selected in various locations in Akure, Ondo State, Nigeria. The locations are Iloyin, Oba-ile and Apatapiti and on these outcrops,in-situ tests were carried out on the outcrops and irregular rock samples were collected for laboratory tests. Schmidt hammer test and Scan line mapping for discontinuities analysis were done on site while sample test for density, specific gravity, average water absorption, point load strength and slake durability were done in the laboratory. The Apatapiti outcrop hasthe highest average density (3.12g/cm3), specific gravity (2.822) and water absorption value (0.84%), while the Iloyin outcrop exhibits the highest average durability (97.88%) and point load strength (5.79MPa), the Oba-Ileoutcrop have the highest compressive strength (190MPa)and average Schmidt hammer hardness value (47.0). The three outcrops volumetric joint count, Jv estimated gave medium block sizes but in the case of block quality of the rockssubjected to evaluation Iloyin happens to be of poor quality while Oba-Ileand Apatapiti outcrop have prospect ofproducing fair quality block. With the information fromthe assessment of block size, block quality and mechanical and physical properties for the rocks consideredin this paper work, it was observed that these three selected outcrop are not good for dimension stone quarry but can be quarried as aggregate stone for construction purposes.
- Bio-flotation of Egyptian Phosphate Using Desulfvibrio Desulfuricans
Abstract: Bio-flotation of Egyptian Phosphate Using Desulfvibrio Desulfuricans Bacteria
Author K. A. SelimN. A. Abdel-KhalekK. E. YassinS. S. Abdalla
The bio-flotation and bio-flocculation processes concern the mineral response to the bacterium presence, which is essentially considered as interplay between microorganism and the physicochemical properties of the mineral surface. The adhesion of microorganisms to minerals results in alteration of surface chemistry of minerals relevant to beneficiation process due to a consequence of the formation of a biofilm on the surface or bio-catalyzed surface oxidation or reduction products. In this paper, the amenability of utilization of Desulfvibrio desulfuricans isolated and adapted on surfaces of phosphate ore, as flotation reagents for separating silica from apatite in the bio-flotation of quartz-apatite minerals system has been studied. The effect of this bacterial isolates on the surface properties of the two single minerals has been studied through zeta potential and adhesion measurements as well as micro-flotation tests. The effect of pH of the medium on the surface properties and flotation behaviour of each single mineral is determined. Flotation of binary mixtures of quartz-apatite as well as natural phosphate ore has also been performed at different operating parameters. Different characterization techniques for both single minerals and bacteria isolated from their surfaces have been done using XRD, SEM, and contact angle as well as morphological and biochemical identification of bacterial isolates.
- Mineral Industry in Egypt – Part II Non-Metallic Commodities
Abstract: Mineral Industry in Egypt – Part II Non-Metallic Commodities –Phosphate Rocks
Author Kh. G. ElmaadawyM. Ezz El DinA. M. KhalidAbdel-Zaher M. Abouzei
Phosphorus is an essential element in the buildup of the human body and all other livings skeletons. The main source of phosphorus is the natural phosphate. About 95 percent of the produced phosphates are consumed in the agricultural sector as fertilizers and animal feed stocks. Most of the balance is converted into phosphoric acid and elemental phosphorus which are the raw materials for manufacturing various phosphate compounds. The world annual phosphate production in 2012 is around 217 million tons, and the global reserves amount to 67 billion tons. With the population increase, researchers estimate that the existing phosphate reserves cover the world needs of phosphates for more than 100 years to come. Egypt has about 4 percent of the world phosphate reserves (2.78 billion tons), and produces about 3 percent of the world phosphate production (about 6 million t/y). The present article covers different aspects of the Egyptian phosphate rocks. The phosphate deposits in Egypt lie between latitudes 23ο 10 – 30ο 50΄ N, whereas the payable zone lies between latitudes 24ο 30΄ – 26ο 50΄ N. They extend longitudinally from the Red Sea Coast to El Dakhla Oases. Geologically, the economic phosphate beds belong to the central facial zone of the Upper Senonian age (Upper Cretaceous and Lower Eocene) deposits. They cover the Red Sea Coast, Nile Valley, and Western Desert. The P2 O5 content ranges between 20 and 32 %. The gangue constituents are mainly carbonates, silica, and silicates (clays), depending on the region and locality. The phosphate ore is mined by open cast and/or underground mining. The underground mining is either long-wall or room-and-pillar mining methods. Upgrading the phosphate rock is done through: crushing, screening, attrition scrubbing, desliming, and drying naturally or artificially. Flotation is a promising technique for the removal of all sorts of gangue minerals. This has been tested in laboratory and semi-pilot scales.