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Grbeš, Anamarija, Ivo Galić, Branimir Farkaš und Ivan Budeš. „MODELLING-FRIENDLY LIFE CYCLE INVENTORY OF UNDERGROUND MINING OF BAUXITE: A CASE STUDY FROM JAJCE MINES IN BOSNIA AND HERZEGOVINA“. Rudarsko-geološko-naftni zbornik 36, Nr. 3 (2021): 59–76. http://dx.doi.org/10.17794/rgn.2021.3.5.
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The objective of this paper is the study of the life cycle inventory (LCI) for underground mining of small, clustered deposits of Dinaric Alps-type bauxites, mined in the mountains near Jajce, a town in Bosnia and Herzegovina, in the period 2010-2020. Modelling of the life cycle inventory was done based on the company’s internal reports and project documentation for a variant of the sublevel caving method that involves drilling and blasting. Four mines, located on three exploitation fields, were found in different phases of mine life, different levels of tectonic disturbances and different types of energy: diesel, electricity, and compressed air. The main results of this study are the inventory of underground bauxite exploitation made based on long-term data, the life cycle of one bauxite deposit, and the emission factors from blasting. Underground mining in this case proved to be energy intensive: an average of 52-92 MJ/t was required (as opposed to 37 MJ/t for surface bauxite exploitation in Italy). At the same time, underground bauxite exploitation caused only 5.6-6.4% of the transformation of natural land that is above the mines and deposits. The operations relying on diesel fuel caused local emissions in the air and underground. The operation relying on electricity for DC locomotive and generation of the compressed air were without local emission into the air, although energy efficiency was probably reduced using compressed air as mechanical energy. At the state level, the impact depends on the country’s energy mix, which is still quite dependent on fossil fuels. Engineering estimates of blasting emissions indicated detonators and ammonium nitrate explosives as a potentially important source of environmental impact. The mining industry would significantly benefit from cleaner energy in electricity generation (the energy sector) in Bosnia and Herzegovina. The path of air emissions in the underground system, especially lead and nitrogen compounds, needs to be further explored.
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Zhu, Zhongping, Xin Teng, Yang Yang, Hao Jiang und Jun Luo. „Flotation Decarbonization and Desulfurization of a High-Sulfur Bauxite in China“. Minerals 13, Nr. 8 (29.07.2023): 1008. http://dx.doi.org/10.3390/min13081008.
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A high sulfur content is one of the challenges in the processing of refractory bauxites in China. The high carbon content of bauxite makes it more difficult to deal with. Desulfurization and decarbonization are the critical issues in the efficient exploitation of high-sulfur bauxite resources. An experimental study on the removal of sulfur and carbon in high-sulfur bauxite is proposed. The sulfur and carbon phases in high-sulfur bauxite were studied via X-ray diffraction and chemistry quantitative analyses. The results show that the sulfur phases in the high-sulfur bauxite mainly exist in the form of sulfide sulfur (pyrite), and the carbon phases in the sample mainly exist in the form of elementary substance carbon. The morphological features of pyrite in the high-sulfur bauxite were analyzed using a microscopic analysis and a scanning electron microscope (SEM). The pyrite exists in minerals in the forms of euhedral, semi-euhedral and other crystalline structures, with a particle size varying from several hundred microns to only a few microns. The raw ore, with a sulfur content of 4.78%, a sulfide sulfur content of 4.20%, a carbon content of 3.10% and an elementary substance carbon content of 2.46% goes through the “one roughing, one cleaning, two scavenging” process after a pre-decarburization, obtaining the total desulfurization recovery of 96.20% with a desulfurization tailing sulfur content of 0.38%, a carbon content of 0.27% and an alumina content of 71.85%, respectively. This work provides technical support for the efficient utilization of high-sulfur and high-carbon bauxite.
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Anagnostou, Ch. „BAUXITE RESOURCE EXPLOITATION IN GREECE VS SUSTAINABILITY“. Bulletin of the Geological Society of Greece 43, Nr. 5 (31.07.2017): 2426. http://dx.doi.org/10.12681/bgsg.11644.
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In the central part of Greece bauxite ore deposits are systematically exploited since more than fifty years, initially by a French industrial group and since few years by a Greek investment group. This “economical” activity uses the non renewable mineral resources of bauxite, non renewable energy sources, as well as significant amount of water and it exports to the environment pollutants andbyproducts. CO2, NOx, F, PAHs are diffused to the atmosphere, polluting the soil of the adjacent area. Big amount of red mud is deviated to the sea, covering an extended shelf area and parts of deeper marine areas. The aim of this work is to evaluate this “economic” activity using principles of the sustainability science. In its broadest definition, sustainability refers to the ability of a society to continue functioning into the future without being forced into decline through the exhaustion or overloading of key resources.
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Mertzanis, A., G. Karetsos, V. Smyrni, G. Efthimiou und G. Zakinthinos. „National Park of Iti: Environmental and geomorphological impacts from the mining activity (Greece)“. Bulletin of the Geological Society of Greece 40, Nr. 4 (01.01.2007): 1833. http://dx.doi.org/10.12681/bgsg.17144.
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Bauxite excavation and the inert material quarries, in the wider region of the "National Park of Iti" in combination with the forest fires, the illegal logging, the grazing and the uncontrollable waste disposal, constituted the most important pressures in it's natural ecosystems. Particularly, bauxite ore exploitation that presented elation during the decade of '70s, was implemented without planning and it caused alterations in the natural environment of the region mainly by the continuous excavations, the foreheads of galleries and the extensive depositions of aggregates materials. As a result, all the above led to the occupation or the deforestation of forests and woodlands, the interruption of natural relief continuity and the change of natural géomorphologie processes. The aim of this work, concerns the determination of the impacts to the environment and more specifically the geomorphes and geomorphological processes, by the bauxite ore exploitation and the quarrying activity, that was developed in the wider region of the "National Park of Iti".
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Borojević Šoštarić, Sibila, Anže Markelj, Eldar Jašarević und Angelika Haindl. „Geological potential of antimony, bauxite, fluorite, and magnesite of the Central Dinarides (Bosnia and Herzegovina): exploration and exploitation perspective“. Geologia Croatica 75, Nr. 2 (23.06.2022): 269–87. http://dx.doi.org/10.4154/gc.2022.16.
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This paper presents the critical raw materials (CRM) potential of antimony, bauxite, fluorite, and magnesite deposits in Bosnia and Herzegovina, discusses their metallogeny and joint geological features, and explains the methodology of the InvestRM application and evaluation criteria for the selected commodities in the following steps: (1) preparation of the geological data templates, (2) evaluation and verification of the geological data, (3) ranking of deposits according to the geological data relating to quality and quantity, and (4) identification of the 10+ perspective deposits. Existing geological datasets show the existence of significant potential in primary CRM such as bauxite (56 Mt), magnesite (4 Mt), and antimony (0.2 Mt) in Bosnia and Herzegovina (BiH). The geological settings of BiH provide favourable metallogenetic conditions primarily for bauxite and magnesite deposits but also for antimony within polymetallic deposits, while fluorspar is rather rare. Our methodology described herein led to the selection of the following fourteen deposits for further geological prospection and investment: the polymetallic antimony deposits Čemernica and Podhrusanj, antimony fields Srebrenica and Rupice; magnesite fields Kladanj, Banja Luka, Teslić and Novi Šeher and bauxite regions Vlasenica-Srebrenica, Grmeč Mountain deposits in Una-Sana region and South Bosnia regions from Posušje to Trebinje. A basic economic calculation based on the world producer ranking and a self-sustainability and economic contribution assessment shows that further investments in geological exploration and mining of antimony, magnesite, and bauxite CRM could place BiH on the list of important producers of these commodities in Europe.
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Pyrgaki, Konstantina, Vasiliki Gemeni, Christos Karkalis, Nikolaos Koukouzas, Petros Koutsovitis und Petros Petrounias. „Geochemical Occurrence of Rare Earth Elements in Mining Waste and Mine Water: A Review“. Minerals 11, Nr. 8 (10.08.2021): 860. http://dx.doi.org/10.3390/min11080860.
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Μining waste, processing by-products and mine water discharges pose a serious threat to the environment as in many cases they contain high concentrations of toxic substances. However, they may also be valuable resources. The main target of the current review is the comparative study of the occurrence of rare earth elements (REE) in mining waste and mine water discharges produced from the exploitation of coal, bauxite, phosphate rock and other ore deposits. Coal combustion ashes, bauxite residue and phosphogypsum present high percentages of critical REEs (up to 41% of the total REE content) with ΣREY content ranging from 77 to 1957.7 ppm. The total REE concentrations in mine discharges from different coal and ore mining areas around the globe are also characterised by a high range of concentrations from 0.25 to 9.8 ppm and from 1.6 to 24.8 ppm, respectively. Acid mine discharges and their associated natural and treatment precipitates seem to be also promising sources of REE if their extraction is coupled with the simultaneous removal of toxic pollutants.
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Oneț, Aurelia, Radu Brejea, Lucian Dincă, Raluca Enescu, Cristian Oneț und Emanuel Besliu. „Evaluation of Biological Characteristics of Soil as Indicator for Sustainable Rehabilitation of a Post-Bauxite-Mining Land“. Diversity 14, Nr. 12 (09.12.2022): 1087. http://dx.doi.org/10.3390/d14121087.
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This paper presents a study of the microbial abundance in post-bauxite-mining land soil from Zece Hotare, Bihor county, Romania. The soil samples were collected from 12 soil variants, in the year 2020, after 15 years of long-term restoration. Some chemical parameters and bacterial numbers of six groups of microorganisms were determined in the restored mining land, and these characteristics were compared with those of the soil from a beech forest situated in an adjacent area unaffected by bauxite exploitation. On the basis of the total number of microorganisms belonging to each group studied, the bacterial potential of the soil quality was assessed, calculating the bacterial soil quality index (BSQI), while the Shannon diversity index and the Jaccard distance were applied to show the level of bacterial diversity. The characteristics of the studied chemical and microbiological parameters determined in the beech adjacent area were very similar to those observed in the high-level plateau, low-level plateau, and Black locust areas, indicating similar soil conditions; therefore, the ecological reconstruction 15 years ago, had a very favorable impact on restoration in some affected areas.
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Wang, Song, Jia Ping Zheng, Xiao Pei Zhang und Shun Ran Wang. „Discussion on the Types Attribution and Comprehensive Utilization of High-Alumina Clay Ore“. Advanced Materials Research 807-809 (September 2013): 2209–14. http://dx.doi.org/10.4028/www.scientific.net/amr.807-809.2209.
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High-Alumina clay ore is the protective exploitation of mineral stipulated by the Ministry of Land and Resources. Due to its physicochemical properties and ore characteristics are quite different from current ore types --refractory clay mineral. It is usually taken as a general refractory clay mine of high-Alumina clay in practical applications, which leads to massive misuse and great waste of high-Alumina clay ore. This paper will redefine the attribuation of high-Alumina clay ore by analysing its differences and similarities with refractory clay minerals and bauxite mines in mineralogy, rock chemistry as well as physical structure, and present some advice on its comprehensive usage aiming at the existed problems in comprehensive development and utilization.
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Khalil, N. M., Yousif Algamal und Qayid M. Saleem. „Exploitation of petroleum waste sludge with local bauxite raw material for producing high-quality refractory ceramics“. Ceramics International 44, Nr. 15 (Oktober 2018): 18516–27. http://dx.doi.org/10.1016/j.ceramint.2018.07.072.
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Kokkaliari, Maria, Eugenia Adam, Andreas Vlachopoulos und Ioannis Iliopoulos. „Tracing Raw Material Sources of Prehistoric Stone Artefacts by Non-Invasive Techniques: The Case of the Early Bronze Age (3rd mill. BCE) Site of Vathy, Astypalaia, Greece“. Quaternary 5, Nr. 4 (09.10.2022): 42. http://dx.doi.org/10.3390/quat5040042.
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Recent findings of archaeological research in the Vathy gulf area, Astypalaia island, indicate its continuous habitation since prehistoric times, most importantly in the transitional period from the Final Neolithic to the Early Bronze Age (late 4th/early 3rd millennium BC). The evaluation of the prehistoric stone artefacts from Vathy using non-invasive analytical methods (Near Infrared Spectroscopy—NIR), in combination with the mineral-petrographic characterization of the main lithological formations of the island, is expected to provide important information about raw material procurement and possible exchange networks. The geological study of the island combined with the analytical methods applied to the archaeological artefacts and the geological samples led to the identification of both local and allogenic materials. The possible locations of raw material sources were established and the origin of allogenic materials was estimated. The stone artefacts made of local geo-materials consist mainly of calcitic sandstone, shale, marl, and limestone/marble, comprising the largest part of the lithological formations of the island, as well as pumice and volcanic rocks of varying chemical composition. By means of a portable microscope and NIR spectroscopy, we were further able to identify allogenic geo-materials including chalcedony, mica schist, bauxite and meta-bauxite, steatite, and paragonite. Based on the mineralogical and petrographic characterization of the stone artefacts, a first attempt is made to evaluate the possible raw material sources and to identify potential intra-island modes of stone exploitation.
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Wardell-Johnson, Grant W., Michael Calver, Neil Burrows und Giovanni Di Virgilio. „Integrating rehabilitation, restoration and conservation for a sustainable jarrah forest future during climate disruption“. Pacific Conservation Biology 21, Nr. 3 (2015): 175. http://dx.doi.org/10.1071/pc15026.
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The environment of the northern jarrah (Eucalyptus marginata) forest (NJF) of Mediterranean-climate, south-western Australia is characterised by deeply weathered soil profiles and low fertility, reflecting long geological stasis. This fire-prone environment is characterised by primary forests of low productivity but high biomass. Since European settlement (1829), the NJF has been structurally transformed by deforestation and resource extraction, including logging and mining (principally for bauxite). Rainfall has declined by 15–20% since 1970, with projections for further decline. A new hydrological regime foreshadows regolith drying, with a changed climate leading to more unplanned, intense fires. Declining productivity, coupled with rehabilitation more suited to a wetter climate, places stress on tree growth and compromises biodiversity. Thus, ecological disruption likely follows from interactions between climate change and historical exploitation. The complex challenges posed by these interactions require multifaceted and novel solutions. We argue that under drying conditions, maintenance of productivity while conserving biodiversity can best be achieved by changing the focus of rehabilitation to the understorey. This would coincide with protecting and restoring surrounding unmined forest with emphasis on the overstorey. Presently, state-of-the-science rehabilitation seeks to restore jarrah forest, following bauxite mining. This goal is unlikely to be achievable across extensive areas under climate change projections. Rather, a focus on restoring understorey following mining would provide a more positive water balance in the wider forest matrix. This approach recognises loss of forest values through mining, but anticipates conservation of biodiversity and important elements of forest structure by minimising ecologically unacceptable disturbance to surrounding forest.
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Pereira Júnior, Antônio, Beatriz Galeno Freitas, Rayssa de Souza Oliveira, Shelda Silva Ferreira Alves, Mariana Bastos de Sousa, Estefany Luz Cabral, Leandro da Silva Andrade et al. „Systematic review on the reclamation of areas degraded by mining“. Research, Society and Development 11, Nr. 8 (07.06.2022): e2711830706. http://dx.doi.org/10.33448/rsd-v11i8.30706.
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The concern with the economic context and the need for metallic and non-metallic minerals in the current state of world globalization, has caused the abandonment of areas degraded by mineral exploration without any action for their recovery. The objective of this research was to analyze literature about the exploitation of mineral resources for various uses, as well as to seek an answer to the guiding question about the importance of the recovery of these areas after extraction. The method applied was a systematic review with quantitative and qualitative coverage. The data analyzed the occurrence of this type of extraction on a global level. In the Asian continent, China (coal for energy) and Indonesia (sand and gravel for construction) accelerate mineral exploration and this causing environmental impacts such as loss of soil fertility by AMD. In the African continent (Au extraction) in the open air and in an artisanal way, which determines the presence of mercury in water bodies. On the European continent, Poland, the chemical degradation due to the exploitation of iron and brown coal, is accentuated; on the South American continent, the exploitation of lithium in the Atacama Desert, of gold (in an artisanal way), bauxite, clay, sand, agate, iron, among others, present abandoned areas and without any type or proposal for their recovery, which is causing loss of endemic flora and fauna. Thus, it is affirmed that the economy and the advance of technology are not associated with the importance of maintaining the balance of natural ecosystems and do not evaluate, or do so in an incipient way, the importance of the recovery of areas degraded by mineral exploration.
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Emerson, Thomas E., und Randall E. Hughes. „Figurines, Flint Clay Sourcing, the Ozark Highlands, and Cahokian Acquisition“. American Antiquity 65, Nr. 1 (Januar 2000): 79–101. http://dx.doi.org/10.2307/2694809.
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AbstractAt the pinnacle of Eastern Woodlands’ prehistoric cultural development, Cahokia has been interpreted as a political and economic power participating in prestige-goods exchanges and trade networks stretching from the Great Plains to the South Atlantic. Among the more spectacular of the Cahokian elite artifacts were stone pipes and figurines made from a distinctive red stone previously identified as Arkansas bauxite. In this research, we used a combination of X-ray diffraction, sequential acid dissolution, and inductively coupled plasma analyses to establish the source of the raw material used in the manufacture of the red figurines and pipes that epitomize the Cahokian-style. Our research demonstrates that these objects were made of locally available flint clays. This finding, in conjunction with other evidence, indicate Cahokian exploitation of many mineral and stone resources focuses on the northern Ozark Highlands to the exclusion of other areas. These findings indicate that we must reassess the direction, extent, and role of Cahokian external contacts and trade in elite goods.
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Cotas Gonçalves, Geovani, und Marco Antonio Alves Garcia. „DIAGNOSIS OF ENVIRONMENTAL RECOVERY IN BAUXITE MINING IN THE MUNICIPALITY OF POÇOS DE CALDAS – MINAS GERAIS“. EPH - International Journal of Science And Engineering 5, Nr. 4 (27.12.2019): 1–7. http://dx.doi.org/10.53555/eijse.v5i4.18.
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This research was conducted in order to evaluate the technical and managerial procedures practiced by a company that carried out the bauxite mining, according to the reference coordinates 23S 343200/7587100, in the municipality of Poços de Caldas – Minas Gerais, with regard to its proposals contained in its Degraded Areas Recovery Plan. The methodology adopted was carried out in four distinct phases: bibliographic research, field data survey through technical visit, analysis of its Degraded Area Recovery Plan and use of geoprocessing techniques for the preparation of two maps: Digital Terrain Model and Slope Map, both prepared by ArcGIS, version 10.3. In addition, aerial images were used in order to compare over the years 2005, 2007, 2015 and 2017. The results obtained recommend topographic leveling actions. The smoothing of the area was not effective, which caused erosive processes present in certain cultivated areas, directly affecting the development of local vegetation. In relation to the techniques of exploitation and reforestation, it was noted that the company adhered to extremely common procedures in the region, such as the use of the method of open pit mining and reforestation with eucalyptus plantations.
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Milutinović, Aleksandar, Aleksandar Ganić und Rade Tokalić. „ACCURACY ASSESSMENT OF GEOMETRICAL ELEMENTS FOR SETTING-OUT IN HORIZONTAL PLANE OF CONVEYING CHAMBERS AT THE BAUXITE MINE »KOSTURI« SREBRENICA“. Archives of Mining Sciences 59, Nr. 1 (01.03.2014): 93–106. http://dx.doi.org/10.2478/amsc-2014-0007.
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Abstract Setting-out of objects on the exploitation field of the mine, both in surface mining and in the underground mines, is determined by the specified setting-out accuracy of reference points, which are best to define spatial position of the object projected. For the purpose of achieving of the specified accuracy, it is necessary to perform a priori accuracy assessment of parameters, which are to be used when performing setting-out. Based on the a priori accuracy assessment, verification of the quality of geometrical setting- -out elements specified in the layout; definition of the accuracy for setting-out of geometrical elements; selection of setting-out method; selection at the type and class of instruments and tools that need to be applied in order to achieve predefined accuracy. The paper displays the accuracy assessment of geometrical elements for setting-out of the main haul gallery, haul downcast and helical conveying downcasts in shape of an inclined helix in horizontal plane, using the example of the underground bauxite mine »Kosturi«, Srebrenica.
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Veress, Márton. „The Effect of Mining Activities on the Paleokarstic Features, Recent Karstic Features, and Karst Water of the Bakony Region (Hungary)“. Mining 2, Nr. 4 (14.11.2022): 757–68. http://dx.doi.org/10.3390/mining2040042.
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This study describes the direct and indirect effects of mining on the karst of the Bakony Region. For this, the results of geological and mining research of the last century, the results of hydrological research of fifty years, as well as the investigations of several decades on the karst of the mountain region are used. Direct effects include the exploitation of filling materials (limonite, kaolinite, manganese ore, and bauxite) from paleokarst features, dolomite rubble, activities exploring or destroying cavities, and the pollution of cavity systems with mining waste (dirt). An indirect effect is karst water extraction. Mining activities (coal and quarrying) resulting in the development of pseudokarstic features are also mentioned here. It can be stated that the effects on the karst and karst features may be permanent and even renewing, but the original state may also have returned or can be expected in the near future. Damages may be local or regional. A regional effect is the decrease in karst water level, which has the most significant effect on the environment, but it has already reached its original state by now.
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Irzon, Ronaldo, Heri Syaeful, Aries Kusworo, Joko Wahyudiono und Ngadenin Ngadenin. „Review on Granitic Rocks in Sumatra: Intrusion Process, Classification, Mineralization and Potential Uses“. EKSPLORIUM 43, Nr. 1 (31.05.2022): 1. http://dx.doi.org/10.17146/eksplorium.2022.43.1.6471.
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Granitic rocks are widely distributed in Sumatra and surrounding areas. These granitoids are classified into several granite provinces of Southeast Asia with different intrusion processes and specific characteristics. This paper aims to review the intrusion of granitic rocks in Sumatra and describe the opportunities associated with it. Granite rocks are used to manufacture cultural heritage, works of art, and ornaments because of their weathering resistance, color diversity, and hardness characters. S-type granite intrusion in Sumatra might be associated with tin mineralization while silver-gold with the I-type. Theoretically, granite contains more REE than other igneous rocks. Mining and extraction difficulties complicate the direct REE exploitation from fresh granite. A-type granite relatively contains more REE than the other types, but this type of granite is not correlated with certain provinces. Indonesia has a tropical climate which is prone to weathering. Therefore, it is possible for REE and/or bauxite enrichments in the granite weathering horizon. Granite is assumed to be a potential source of uranium and thorium, especially for the S-type, because it is formed through the compression of sediments that can absorb these radioactive elements from the continental crust.
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Gebara, Jonas, Antenor Pereira Barbosa, Isabel Maria Gonçalves Azevedo und Bruno Oliva Gimenez. „POPULATION STRUCTURE AND PRODUCTION OF COPAIBA OLEORESIN BETWEEN VALLEYS AND HILLSIDES OF THE MINING AREA OFTROMBETAS RIVER - PARÁ1“. Revista Árvore 40, Nr. 1 (Februar 2016): 51–60. http://dx.doi.org/10.1590/0100-67622016000100006.
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ABSTRACT We aimed in this work to study natural populations of copaiba (Copaifera multijuga Hayne) on the Monte Branco mountain at Porto Trombetas-PA, in order to support sustainable management and the exploitation of oleoresin from copaiba. We studied the population structure of copaiba on hillsides and valleys of the south face of Monte Branco, within Saracá Taquera National Forest, where bauxite ore was extracted in the biennium 2013-2014 by Mineração Rio do Norte (MRN). We produced a 100% forest inventory of the specie and of oleoresin extraction in order to quantify the potential production of the remaining area. The density of copaiba individuals with DBH > 30 cm was 0.33 individuals per hectare in the hillside and 0.25 individuals per hectare in the valley. Both environments presented a density of 0.28 individuals per hectare. The average copaiba oleoresin yield was 0.661±0.334 liters in the hillside and 0.765±0.280 liters in the valley. The average value of both environments together (hillside and valley) was 0.714±0.218 liters. From all individuals with DBH over 30 cm, 38 (58%) produced some amount of oleoresin, averaging 1.113±0.562 liters in the hillside, 1.329±0.448 liters in the valley and 1.190±0.355 liters in both environments together. The results show the need for planning the use of the surroundings of the study area in order to reach the required volume of copaiba to make feasible the sustainable management of oleoresin extraction in the region.
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Bhoyi BALDÉ, Mamadou, Abdoulaye BAH und Ibrahima BAYO. „Contribution to the Study of Water Pollution in the Nunez River estuary, (Republic of Guinea)“. International Journal of Research and Review 10, Nr. 8 (01.09.2023): 1090–99. http://dx.doi.org/10.52403/ijrr.202308137.
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Bauxite mining offers an important livelihood strategy, a source of economic and social development relevant to countries with this natural wealth. It emerges, from the observations and extensive bibliographical reviews, that this exploitation has direct impacts on estuarine ecosystems through the establishment of ports and mining industries, hence our research theme "Contribution to the study of the impacts of industrial activities on the estuarine ecosystem of the Nunez River" In addition, the observation on the ground tells us that despite the efforts made by the authorities through the competent institutions and the investors, reducing the environmental impacts generated by this mining operation often has problems and insufficient capacity to deal with them, as revealed by our study conducted on the Nunez estuary. The hypothesis of this theme can be summarized as follows: The negative effects of the major pollutants of the Nunez River estuary due to the installation of industrial units, associated with the impacts related to climate change in the locality contribute to the dysfunction of the estuary, in turn to the reduction of opportunities and ecosystem services offered by the Nunez River. Nevertheless, given the high variability of the recorded values of the physicochemical parameters of the estuarine waters (temperature, pH, electrical conductivity, turbidity, salinity, dissolved oxygen, nitrate, nitrite, dissolved solids, suspended solids and phosphate) it seemed necessary to study them. Eleven sampling sites served as a study framework, the CERE/UGANC laboratory, as an analytical framework. Keywords: Industrial activities, estuarine ecosystems, environmental impacts, pollution.
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TODERAȘ, Alina. „Using G.I.S. Products for Analysing the Potential of Practising Sustainable Tourism and Developing Z e ce Hotare Village“. Territorial Identity and Development 5, Nr. 1 (11.09.2020): 68–98. http://dx.doi.org/10.23740/tid120204.
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Zece Hotare village (Bihor County, Romania) is part of the disadvantaged areas category, being a former mining village, due to the exploitation of bauxite and clay resources. Today, its socio-economic situation is precarious, the economic sector being poorly developed, and the population is constantly declining. At present, it is an agricultural and forestry village. One of the solutions that could lead to achieving a balance and improving the economic situation and maintaining the existing population in the village, would be to capitalize on local resources by practicing rural tourism, in particular agritourism. Although recreational tourism is sometimes practised, agritourism is currently non-existent within the area. However, by practicing agritourism, the specific values, customs and traditions would be promoted. This study aims to propose and analyse possible options for the development of rural tourism, mountain tourism, ecotourism, agritourism, and cycling tourism, as well as which activities should be undertaken to practise these forms of tourism and to attracting tourist flows towards Zece Hotare village. Some of the proposals for tourism development in Zece Hotare provided in the study are as follows: construction of boarding houses; presentations addressed to locals about what the practice of agritourism involves, in order to observe their degree of openness and availability to contribute to practicing this form of tourism as hosts; creating thematic paths for picking medicinal plants; creating a cycle tourist route that includes a tour of the hamlets in the village; building boutiques where locals can sell their products, such as honey, bakery products, woven and embroidered clothes, wooden objects, etc.; arranging places for camping, arranging places for leisure activities, and others.
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Muzahar und Agus Alim Hakim. „SPAWNING AND DEVELOPMENT OF DOG CONCH Strombus sp. LARVAE IN THE LABORATORY“. Jurnal Ilmu dan Teknologi Kelautan Tropis 10, Nr. 1 (01.04.2018): 209–16. http://dx.doi.org/10.29244/jitkt.v10i1.18607.
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An intensive exploitation of dog conch Strombus sp. in Tanjungpinang city coastal waters has occurred because the increasing number of fishermen, population growth and demand. In addition, the increasing activities of bauxite mining cause the declining in quality of waters around dog conch, thus providing ecological pressure that endangers sustainability of the dog conch. The purpose of this study was to observe the spawning and development of dog conch in the laboratory. Spawning was done in aquarium with 100 liters of seawater (salinity: 26±1 ppt), with stimulation of spawning performed by changing 90% water volume every day until the female issued the eggs. The female issued the eggs on the third and fourth days of stimulation. Eggs are attached to the wall of the aquarium. Egg cell division occurs after about 2 hours of the egg is released the mother, from one cell into two cells and a row into four cells, eight cells, the sixteen cells, thirty-two cells to multicellular. The embryo develops into a gastrula phase than trochophore phase. Larvae were reared in a tank containing 20 liters of seawater (salinity: 26±1 ppt). Veliger larvae occurred on the fifth day until the eleventh day. Veliger larvae are planktonic, and turn into benthic with a sedentary life in the bottom waters to begin the formation of a thin and transparent shell. The value of water quality parameters during maintenance category feasible: DO of 7.6 to 7.8 mg / L; pH of 8.13 to 8.33; turbidity of 1.97 to 3.90 NTU, salinity of 26.8 to 27.8 ppt; and temperature of 25.8-27.8°C.
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Carnicero, D., E. Díaz, O. Escolano, D. Rubinos, O. Ballesteros, M. T. Barral, R. Amils und F. J. García Frutos. „Preliminary Study of Neutralization and Inhibition of Chemolitotrophic Bacteria in an Acid Mine Drainage from Rio Tinto Site“. Advanced Materials Research 71-73 (Mai 2009): 677–80. http://dx.doi.org/10.4028/www.scientific.net/amr.71-73.677.
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Limestone is commonly used for neutralization of acid mine drainage (AMD). Its main advantages are its lower price, sustained generation of alkalinity and production of low sludge volumes. Nevertheless, armouring of limestone by ferric hydroxides is a problem in oxic limestone drains and in active limestone treatment systems, reducing the efficiency of the process. Due to these disadvantages, there is a permanent search for cheaper and more effective neutralization agents. Many alkaline industrial wastes are gaining importance in the treatment of AMD. The possibilities to use two different industrial by-products, red mud from a bauxite exploitation and low grade magnesium hydroxide from a magnesite mine, as neutralizing and bacterial inhibiting agents, and the comparison with conventional limestone treatment has been studied in this paper. An AMD from Rio Tinto mine site with an initial pH of 2.4 and a ferric concentration of 1 g/L was used. Comparative test were done percolating the AMD in a continuous form with a peristaltic pump through three different columns filled with limestone, red mud and low grade magnesite, during one month and in same conditions of flow rate and amount of each compound used to fill the columns. The evolution of pH, iron and heavy metals, sulphates and microbial populations in the percolate were monitored at different times. The results showed that the best neutralization capacity was obtained with low grade magnesite during the month treatment. By contraire limestone and red mud loosed their neutralization capacity after 10 and 13 days respectively. The control of microbial populations showed that there is an inhibition of chemolithotropic bacteria as long as the materials maintain their neutralization capacity, reverting to the initial conditions when this capacity was loosed.
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Diallo, Yaya Kenda Baïlo, und Ahmed Amara Konaté. „Hydrogeochemical characterization of the areas of exploitation of the CBG sites: cas of the plateaus of N'Dangara and Boundou Wandé, Sous-préfecture de Sangarédi, Prefecture of Boké, Republic of Guinea“. Acta Scientifica Naturalis 10, Nr. 2 (01.07.2023): 1–24. http://dx.doi.org/10.2478/asn-2023-0011.
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Abstract This work aims to analyze the quality of groundwater in the riparian areas of the bauxitic plateaus of N'Dangara and Boundou Wandé in operation by the CBG (Compagnie des Bauxites de Guinée). The geology of the study area consists mainly of sedimentary formations of the Devonian faro, Neogene and Quaternary. Three water measurement and sampling campaigns on the two plateaus were carried out with determination of piezometric measurements and physic-chemical parameters. This study showed that the general flow direction of groundwater is dispersed. The flows at Boundou Wandé are from the center of the plateau to the north and that at N'Dangara is from the center to the south and southwest. It can be seen that the direction of groundwater flow reflects overall the relief of the deposit conditioned by its geomorphological framework. It emerges from the analysis of physical and chemical parameters that well water is consumable. However, the water from wells MW15, MW16, MW17, MW18 and MW21 with a low pH (4.84 to 5.13) may present a certain nuisance for its consumption and because it can be corrosive. Analysis of the Piper diagram showed two hydrogeochemical facies (calcium and magnesium bicarbonate facies and sodium and potassium carbonate facies). However, this study strongly suggests continuous monitoring of groundwater in and around the study area in order to meet the demand for water supply to communities without compromising the ability of future generations to meet water quality requirements.
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Narasimha Murthy, Ayapilla. „Extraction of Sand from Waste dumps of Mining: A New Approach to Address the Environmental Issue of Goa“. Asian Review of Civil Engineering 10, Nr. 1 (15.05.2021): 1–3. http://dx.doi.org/10.51983/tarce-2021.10.1.2797.
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Goa is India's smallest state by area (3700 sq.km) but rich of mineral deposits such as -iron ore, manganese ore, bauxite and many minor minerals like basalt, laterite stones, rubbles, river sand etc., Exploration and exploitation for iron ore has started at the beginning of the 20th century. Iron ore mining in Goa is completely in the private sector. The mining belts extend over a length of 65km from SE to NW of the State covering around 700 sq.km. The iron ore deposits are distributed over the Northern, southern, and central blocks of Goa. It is the only state with large area under mining. Mineral production in Goa started in the late 1940s. Initially with Manganese ore but later shifted to iron ore with phenomenal growth in production. Every year around 60million tonnes of iron ore was being handled till 2015. Subsequently capping has been imposed by Hon’ble Supreme Court to mine 20 million tonnes from 100 mines by open cast method to control the pollution levels. The mining is carried out by mechanized methods and generated large number of employments, around 5 lakh people by both direct and indirect means. The state is having 400 million tonnes of iron ore resources. The highest production of iron ore from Goa was 40 million tonnes per annum in the past, but for extraction of everyone tonne of ore approximately 4 tonnes of waste rock has to be removed as the mining has gone deep and extent of each lease area is small. The waste rock comprises manganiferous and phyletic clays which are soft and easily erodible. Further, Goa witnesses heavy rainfall up to 3500mm during SW monsoon every year, thus the surface waters are getting polluted. As said above the lease areas are being small and the generation of waste rock is high. So, the disposal of waste rock and its prevention poses a problem. The analysis of waste rock indicates the waste rock is rich of sand grains which can be extractable by simple crushing and screening method. So, a detailed conceptual plan is necessary to sustain the mining and to tackle the environmental issues which are suggested in this paper.
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Vikentiev, I. V. „Critical and Strategic Minerals in the Russian Federation“. Геология рудных месторождений 65, Nr. 5 (01.09.2023): 463–75. http://dx.doi.org/10.31857/s0016777023050106.
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Global development and scientific and technological progress are intensifying the use of mineralraw materials (MRMs)—the necessary basis for the production of high-tech products. The advanced producing countries of these products are in dire need of various raw materials, which are critical and, as a rule, are supplied from third countries. Strategic is a mineral raw material, which is of particular importance for ensuring the economic development of the country, its defense and security. Due to the complex structure of extraction, processing and consumption of raw materials, many of its types are in short supply. In the world literature, the concept of “deficient MRMs” in its content most closely corresponds to “critical MRMs,” that is, raw materials that are critically needed for industry and are characterized by a significant risk of their supplies. Most critical raw materials are needed for production promising high-tech industrial products and new materials and, in particular, for “green technologies” in connection with the course of decarbonization of the economy actively pursued by world powers. In the production of such products, the consumption of MRMs is growing rapidly, especially rare-earth elements (REEs), V, Li and platinum-group elements (PGEs). From the list of 61 kinds of MRMs that are strategic for Russia, the extraction of oil, gas, Cu, Au, PGEs, Ni, apatite ores, K salts, and diamonds (as well as nonlisted coals, Fe ores, Na salts, V, B ores, magnesite, and chrysotile asbestos) fully covers their current domestic consumption in the Russian Federation and the achieved level of export. U, Mn, and Cr ores; Zr; high-purity quartz raw materials (SiO2); bauxite (Al); graphite; fluorite and nonstrategic barite; kaolin; and bentonite are deficient; their exploitation only partially provides domestic consumption, which is largely dependent on imports; it is carried out in insufficient volumes in the presence of significant reserves of relatively low quality. The most deficient in this list are Ti, Li, Ta, Nb, and REEs (usually, there are groups of heavy and light rare earths (HREEs and LREEs, respectively)): their domestic consumption is provided mainly by imports with very limited production (despite large reserves, including low quality ores). Re, Be, Nb, Ta, HREEs, Y, Sc, LREEs, Ge, Ga, Li, Hf, and Co, and, of nonstrategic MRMs, Bi and Sr, should be considered critical MRMs in the Russian Federation. The most important source of dispersed/ associated elements is represented by raw materials of mining enterprises of nonferrous metallurgy: Cu and Zn subsectors, In, Ge, Ga, Cd, Tl, Se, Te, Sb, Bi, etc.; Al subsectors, Ga; for Au and Au–Ag deposits, Sb, As, Te, Se, Bi, Tl. An associated source of lithium is represented by brines of gas-condensate fields. The issues of assessing complex raw materials for high-tech industry are considered using the example of pyrite, porphyry, and gold-ore deposits of the Ural folded region, which play an important role in its overall metallogenic potential.
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Mo, Hongcheng, Ruidong Yang, Chaokun Luo, Xinzheng Li, Yanbing Ji, Guiyuan Yang, Xumei Zhou, Chuanqian Gao, Xu Hu und Zhimeng Zeng. „Effect of Karst Geomorphology on the Sedimentary Mineralization and Geochemical Distribution of Bauxite: An Example from the Xiaoyuan Area in Qingzhen, Guizhou Province“. Minerals 13, Nr. 8 (29.07.2023): 1013. http://dx.doi.org/10.3390/min13081013.
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Bauxite, in central Guizhou, is predominantly karst bauxite, but there is insufficient research on the effect of karst paleogeomorphology on bauxite development. Xiaoyuan bauxite is also a karst bauxite, and high- and low-iron bauxite deposits exist in the study area. This study conducts geological modeling of karst bauxite using controlled-source audio-frequency magnetotelluric (CSAMT) data and drill core data. The effects of karst paleogeomorphology on bauxite deposition and mineralization are evaluated by assessing karst paleogeomorphology, conducting a mineralogical analysis of drill cores at different locations, and determining the geochemical distribution characteristics of the elements in the horizontal and vertical directions. Combined with previous research results, we propose two metallogenic processes of high-iron and low-iron bauxite. The findings are significant for understanding the mechanism of bauxite formation.
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Winarno, Tri, Rinal K. Ali, Harrys Simangunsong und Almiftahurrizqi Almiftahurrizqi. „Characteristics and Genesis of Laterite Bauxite in Sompak District and Surrounding Areas, Landak Regency, West Kalimantan“. Indonesian Journal on Geoscience 10, Nr. 1 (05.01.2023): 37–49. http://dx.doi.org/10.17014/ijog.10.1.37-49.
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West Kalimantan has very large bauxite resources, reaching 2.07 billion tons, equivalent to 57.32% of the total bauxite resources in Indonesia with bauxite reserves of 0.84 billion tons or equivalent to 66.77% of the total national mineral reserves. The researched area covers Sompak District and surrounding areas, Landak Regency, West Kalimantan. This research aims to determine geological conditions, laterization, and characteristics of laterite bauxite in the studied area. Methods used in this research are geological mapping, lateritic mapping, and petrographic and geochemical analyses. The lithology of the researched area is composed of granodiorite, porphyry quartz diorite, granite, porphyry andesite, porphyry basalt, alluvial, and swamp deposits. Laterite profiles in the researched area generally consist of topsoil, latosol, bauxite, and clay zone. The laterite bauxite derived from granodiorite is classified as a medium grade, laterite bauxite from porphyry quartz diorite is classified as high-grade bauxite, laterite bauxite from andesite porphyry is classified as low-medium grade bauxite, and laterite bauxite from porphyry basalt in the studied area is classified as high grade bauxite. Laterite bauxites in the researched area were formed from weathered parent rocks which were intermediate - alkaline igneous rock.
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Verma, Ajay S., Narendra M. Suri und Suman Kant. „Applications of bauxite residue: A mini-review“. Waste Management & Research: The Journal for a Sustainable Circular Economy 35, Nr. 10 (06.09.2017): 999–1012. http://dx.doi.org/10.1177/0734242x17720290.
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Bauxite residue is the waste generated during alumina production by Bayer’s process. The amount of bauxite residue (40–50 wt%) generated depends on the quality of bauxite ore used for the processing. High alkalinity and high caustic content in bauxite residue causes environmental risk for fertile soil and ground water contamination. The caustic (NaOH) content in bauxite residue leads to human health risks, like dermal problems and irritation to eyes. Moreover, disposal of bauxite residue requires a large area; such problems can only be minimised by utilising bauxite residue effectively. For two decades, bauxite residue has been used as a binder in cement industries and filler/reinforcement for composite materials in the automobile industry. Valuable metals and oxides, like alumina (Al2O3), titanium oxide (TiO2) and iron oxide Fe2O3, were extracted from bauxite residue to reduce waste. Bauxite residue was utilised in construction and structure industries to make geopolymers. It was also used in the making of glass-ceramics and a coating material. Recently bauxite residue has been utilised to extract rare earth elements like scandium (Sc), yttrium (Y), lanthanum (La), cerium (Ce), neodymium (Nd) and dysprosium (Dy). In this review article, the mineralogical characteristics of bauxite residue are summarised and current progresses on utilisation of bauxite residue in different fields of science and engineering are presented in detail.
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Sun, Fengyu, Changling Qu, Gaoshe Cao, Liqin Xie, Xiaohu Shi, Shengtao Luo, Zhuang Liu et al. „Oolitic Sedimentary Characteristics of the Upper Paleozoic Bauxite Series in the Eastern Ordos Basin and Its Significance for Oil and Gas Reservoirs“. Processes 12, Nr. 10 (29.09.2024): 2123. http://dx.doi.org/10.3390/pr12102123.
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In recent years, great breakthroughs have been made in gas explorations of the Upper Paleozoic bauxite series in the Longdong area of the Ordos Basin, challenging the understanding that bauxite is not an effective reservoir. Moreover, studying the reservoir characteristics of bauxite is crucial for oil and gas exploration. Taking the bauxite series in the Longdong area as an example, this study systematically collects data from previous publications and analyzes the petrology, mineralogy, oolitic micro-morphology, chemical composition, and other sedimentary characteristics of the bauxite series in the study area using field outcrops, core observations, rock slices, cast slices, X-ray diffraction analysis, scanning electron microscopy and energy spectra, and so on. In this study, the oolitic microscopic characteristics of the bauxite reservoir and the significance of oil and gas reservoirs are described. The results show that the main minerals in the bauxite reservoir are boehmite and clay minerals composed of 73.5–96.5% boehmite, with an average of 90.82%. The rocks are mainly bauxitic mudstone and bauxite. A large number of oolites are observable in the bauxite series, and corrosion pores and intercrystalline pores about 8–20 μm in size have generally developed. These pores are important storage spaces in the reservoir. The brittleness index of the bauxite series was found to be as high as 99.3%, which is conducive to subsequent mining and fracturing. The main gas source rocks of oolitic bauxite rock and the Paleozoic gas series are the coal measure source rocks of the Upper Paleozoic. The oolitic bauxite reservoirs in the study area generally have obvious gas content, but the continuity of the planar distribution of the bauxite reservoirs is poor, providing a scientific basis for studying bauxite reservoirs and improving the exploratory effects of bauxite gas reservoirs.
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Nguyen, Minh Van, und Hau Van Nguyen. „Recovery of bauxite ore particles -1mm from tailings of the Tan Rai bauxite processing plant by mechianical classifiers“. Journal of Mining and Earth Sciences 62, Nr. 3b (20.07.2021): 51–57. http://dx.doi.org/10.46326/jmes.2021.62(3b).06.
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Tailings of the Tan Rai bauxite mineral processing plant contain a relatively high proportion of fine bauxite ore particles of less than 1mm. This amount of discarded fine bauxite particles necessarily leads to a high loss of valuable bauxite mineral and also require more tailings dam space. Recovery of such fine bauxite ore particles may produce certain economic and environmental effects to the current processing plant. The paper presents results of the study on recovery of fine bauxite ore particles -1 mm from tailings of the Tan Rai - Lam Dong bauxite mineral processing plant by the use of mechanical classifiers. The obtained +0.5 mm bauxite concentrate are suitable for blending with the +1 mm concentrate of the current plant. The study results showed that recovery of fine bauxite ore particles -1mm from the plant tailings may produce additional amount of valuable concentrate to ensure the supply requirements to the alumina plant and also add some values to the effective mineral resource utilization and bring some economic efficiency.
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Zhang, Peng, Xianghui Jing, Renhai Pu, Aiguo Wang und Xueping Huang. „Logging Identification and Distribution of Bauxite in the Southwest Ordos Basin“. Minerals 13, Nr. 10 (25.09.2023): 1253. http://dx.doi.org/10.3390/min13101253.
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In recent years, with the discovery of oil and gas in the Carboniferous bauxite reservoir in the Ordos basin, the formation and distribution of bauxite and bauxite reservoirs have attracted the attention of oil and gas explorers. Based on the slightly equidistant core testing of minerals and the porosity on the formation and calibration on the logging curves, we established a logging identification method for bauxite in the study area and fitted the formula for calculating the diaspore content and porosity using logging data. By applying this formula and a large amount of logging data, thickness and porosity maps of the Taiyuan formation of bauxite in the southeastern part of the basin were produced. Then, according to the thickness of the earliest deposited Taiyuan formation on the unconformity surface, we analyzed the paleogeomorphology of the bauxite deposition. Finally, a sedimentary facies map of the Taiyuan formation was developed based on the content of sandstone, coal seams, and carbonate rocks contained there. The results show that the diaspore content of bauxite is positively correlated with the natural gamma logging (GR) values. According to the diaspore contents and the GR values, the aluminiferous rocks in the Taiyuan formation can be divided into three categories: ① Bauxite for GR values > 450 API and diaspore content >70%; ② Argillaceous bauxite for GR values = 300–450 API and diaspore content = 25%–70%; and ③ Bauxitic mudstone for GR values = 220–300 API and diaspore content = 0%–25%. Bauxite mainly occurred in the middle and deep lagoon environments in the lower part of the Taiyuan formation. The lagoon is distributed along the paleokarst groove in the NW strike, with a width of approximately 30–40 km and a length of approximately 150–200 km, among which the thickness of pure bauxite is 9 m, argillaceous bauxite 26 m and alumina mudstone 6 m. Bauxite with a high porosity mainly existed in pure bauxite. The lagoon bauxite in the lower part of the Taiyuan formation gradually changes upward into a tidal flat swamp and carbonate platform environment.
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Thevi, T., und A. L. Abas. „Effects of Bauxite and Alumina Exposure on Incidence of Cancer - Meta-analysis“. Kathmandu University Medical Journal 18, Nr. 4 (31.12.2020): 414–19. http://dx.doi.org/10.3126/kumj.v18i4.49256.
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Bauxite is an ore from which Aluminium is produced. Malaysia, once the leading producer of bauxite has reduced production as mining activity has caused community outrage. Due to concerns about health concerns, rising pollution and environmental hazards, the government has revoked the licenses of bauxite miners. We therefore did a meta-analysis to assess the relationship between exposure to Bauxite and Alumina with incidence of various types of cancers. Bauxite mines and alumina refineries. Individuals of all ages exposed to Bauxite and Alumina.
Exposure to bauxite and alumina. Incidence due to overall cancers and specific types of cancers. Exposure to bauxite and alumina did not cause variations in incidence of overall cancer and specific types of cancer such as cancer of lip, cancer of the oral cavity and pharynx, cancer of digestive organs and others. We conclude that there is no evidence that bauxite or alumina exposure cause increase incidence of cancer but due to the small number of studies included in this review, we recommend more cohort studies to be done in future.
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Cui, Tao. „Mineralizaton Process of the Bauxite in WZD Area“. Advanced Materials Research 989-994 (Juli 2014): 1269–72. http://dx.doi.org/10.4028/www.scientific.net/amr.989-994.1269.
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This paper has a comprehensive analysis on mineralizaton process of the bauxite in Wuchuan-Zheng, an-Daozhen (WZD) area, northern Guizhou, China through synthesize former research. Geologic characteristic demonstrates that WZD bauxite is a typical sedimentary deposit, minerogenetic material have experienced a transporting process. Sedimentary environment of WZD bauxite is transition facies. Sedimentary environment is reduced and acidic. Accompanying frequent transgression and regression, bauxite has suffered a leaching process. In the leached period, environment is oxidized and acidic. Leaching process is the most important factor for the information of high grade bauxite. WZD bauxite has experienced several times leaching resulting in the great runoff of Fe and Si. Actually the metallogenetic process of WZD bauxite is a process that Al relative enrichment but Si and Fe runoff.
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Fu, Si Feng. „Mining Exploration of Bauxite Based on High-Power Electrical Method“. Applied Mechanics and Materials 340 (Juli 2013): 966–70. http://dx.doi.org/10.4028/www.scientific.net/amm.340.966.
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This article gives the basic deposition of the western sedimentary bauxite strata in Henan Province. Bauxite deposition formation and its surrounding rock geophysical characteristics; the bauxite layer rock has a series of low resistivity low polarization characteristics. Ordovician limestone has obvious high impedance polarization characteristics, which makes the use of resistors Department of Law exploration become possible. It explores the use of high-power electrical method exploration bauxite technology, and describes how to use the results of investigation of high-power electrical method inferred bauxite body. And it takes the examples of high-power electrical method in looking for bauxite effective.
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Economou-Eliopoulos, Maria, und Christos Kanellopoulos. „Abundance and Genetic Significance of Lithium in Karst-Type Bauxite Deposits: A Comparative Review“. Minerals 13, Nr. 7 (19.07.2023): 962. http://dx.doi.org/10.3390/min13070962.
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Palaeo weathering during the Cretaceous–Eocene interval is most favorable for bauxitization, i.e., transport and deposition in traps on the karstified surfaces of the Mediterranean karst bauxite belt, including the Parnassos–Ghiona bauxite deposit. Resources of lithium (Li), a critical metal of strategic significance in karst-type bauxite deposits, have attracted significant attention in recent years. Due to the discovery of the Li enrichment in certain karstic bauxite deposits in Europe and particularly in China, this review study is focused on the unexplored Li content in the Parnassos–Ghiona (Greece) bauxite deposit, aiming to improve the understanding of the major controlling factors for their origin and enrichment of critical metals. The presence of thin (up to 50 cm) pyrite-bearing coal seams and carbonaceous facies on top of the Parnassos–Ghiona bauxite deposit, at the transition between B3 (the youngest) bauxite horizon and the occurrence of multicolor bauxite ores reflecting a multistage evolution and changes in the mineralogy and geochemistry, is a common feature with other bauxite deposits in Europe and elsewhere. The organic matter, such as microorganisms in coal layers and carbonaceous layers (derived from plants and algae growing in paleo-mires after a regression of the sea), contains Li, which is derived from seawater, as suggested by a positive correlation with B (a seawater component as well). The available geological, mineralogical, and geochemical data highlight the particular significance of coal layers and carbonaceous layers overlying bauxite bodies as a driving force for redox reactions and as a source of Li in the exploration of karst-type bauxite deposits.
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Mildan, Deni, Andri S. Subandrio, Prayatna Bangun und Dedi Sunjaya. „Contrasting Genesis of Lateritic Bauxite on Granodioritic and Andesitic Rocks of Mempawah Area, West Kalimantan“. Indonesian Association of Geologists Journal 1, Nr. 2 (31.08.2021): 81–88. http://dx.doi.org/10.51835/iagij.2021.1.2.33.
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The lateritic bauxite deposits in the Mempawah area, West Kalimantan, were formed by the chemical weathering of Cretaceous granodioritic and andesitic rocks. They occurred locally on the low hills surrounded by swampy areas. Detailed surface geological mapping, test pits, mineralogical and geochemical analyses were performed to determine the characteristics and genesis of bauxite from different parent rocks. From bottom upward, the deposits are composed of fresh parent rocks, clay or pallid zone, bauxite zone with a few sparse ferricrete at the top of the bauxite zone, and soil. Bauxite derived from granodiorite exhibits brownish-red, massive, boulder to gravel-sized concretion in clay matrix and is composed of predominant gibbsite with subordinate kaolinite, quartz, goethite, and a minor amount of magnetite and hematite. In contrast, bauxite derived from andesitic rocks exhibits reddish-brown and is composed of predominant goethite. During the leaching process, SiO2 as a mobile compound decreased significantly in neutral pH, while Al2O3 and Fe2O3 precipitated as residual materials to form bauxite concretion. The enrichment anomaly of bauxite derived from andesitic rocks is caused by physio-chemical changes from hydrothermal alteration. Bauxite was formed by indirect bauxitization through the leaching of primary minerals under a tropical-humid climate.
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Yang, Zhifeng, und Junjie Zhao. „Geological Features and Ore Formation Pattern of Jinzhong Bauxite Mine, Shanxi Province, China“. Scientific and Social Research 6, Nr. 10 (05.11.2024): 82–89. http://dx.doi.org/10.26689/ssr.v6i10.8530.
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Bauxite is located in the lower part of the Benxi Formation, and the prospecting project shows that the distribution of bauxite ore bodies in the area is discontinuous, and there are differences in the thickness of the ore bodies. To have a clearer understanding of the bauxite ore bodies and metallogenic pattern in the census area, this study has made use of the prospecting project data, sample analysis results, etc., and combined with the geological and tectonic background of the area, the stratigraphic spreading characteristics of the bauxite ore body spatial spreading, ore characteristics and ore controlling factors in the area have been explored and researched. The bauxite ore bodies in the study area are stratified but the ore-bearing rock system is influenced by the Ordovician paleokarst geomorphology and intermittently distributed horizontally, which can be distinguished into three different ore bodies. The bauxite ore body and Shanxi-style iron ore are associated with hard clay ore, in which the ore minerals are mainly monohydrate duralumin. The natural ore type can be divided into dense bauxite and oolitic bauxite. Bauxite in this area mainly originated from the basal Ordovician carbonate rocks, with a combination of iron-rich and aluminum-rich layers, and is a typical carbonate rock sedimentary deposit of ancient weathering crust.
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An, Jian Cheng, Lin Jun Wang und Yun Sheng Feng. „Industrial Production and Application in LCCs of Bauxite-Based Homogenized Grogs“. Advanced Materials Research 287-290 (Juli 2011): 1079–83. http://dx.doi.org/10.4028/www.scientific.net/amr.287-290.1079.
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The Bauxite-based Homogenized Grog (BHG) was industrial producted using bauxite with about 70 wt.% Al2O3 as starting materials and its properties were tested. Through comparing with high-grade bauxite clinker, the applications in LCCs of BHG and bauxite clinker were discussed. The results showed that the BHG with mullite as chief phase, with consistent components and structure and properties using middle or low grade bauxite as starting materials can been prepared industrially by homogenization process, vacuum-extrusion moulding and high-temperature sintering method. It also resulted that the BHG can replace competently high-grade bauxite clinker to apply in LCCs as coarses and the LCCs with BHG as coarses have more outstanding properties.
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Cui, Tao. „Preservative Features of the Fossils in Bauxite Deposit of WZD Area, Northern Guizhou, China“. Advanced Materials Research 989-994 (Juli 2014): 1384–87. http://dx.doi.org/10.4028/www.scientific.net/amr.989-994.1384.
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It is hardly to discovery fossil from the bauxite in Wuchuan-Zheng, an-Daozhen (WZD) area, northern Guizhou, China. But the new study suggests, containing a small amount of plant debris from massive bauxite in the lower part of the ledge. Preservative features of fossils in WZD bauxite indicates: metallogenetic materials experienced a transport process; sedimentary environment is reduced; fossils only preserved in the massive bauxite, that fossils in other types of ores were destroyed in the late oxidation modification. Metallogenic environment of bauxite has experienced two kinds of state-reduction and oxidation. The lack of animal fossils; bauxite, reveal that the metallogenic environment is acidic, resulting in animal fossils are dissolved and hard to save.
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Wu, Xirong, Nanxiang Zhen und Fansheng Kong. „Effect of Characteristics of Different Types of Bauxite Clinker on Adhesion“. Applied Sciences 9, Nr. 22 (07.11.2019): 4746. http://dx.doi.org/10.3390/app9224746.
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Based on the fact that bauxite clinker has minor thermal conductivity and better skid resistance and wear-resisting property, it can be used in HFST (high friction surface treatment) or the abrasion layer of asphalt mixture to replace or partly replace the existing aggregate. Bauxite clinker is classified into mainly six types according to different chemical composition contents. The selection of bauxite clinker as aggregate is not only for the economic value, but also for improving the adhesion between aggregate and asphalt, which has a certain blindness This study evaluated the characteristics of different types of bauxite clinker. The adhesion of different types of bauxite clinker with asphalt was evaluated by means of agitating hydrostatic adsorption method and surface free energy theory. The effect of characteristic parameters of bauxite clinker on adhesion was evaluated by grey correlation entropy analysis. The results show that Type B and D bauxite clinker aggregates have the best adhesion to asphalt. The outcome of grey entropy correlation analysis shows that the parameters which characterize the structural indexes of bauxite clinker, such as porosity, water absorption and apparent density, have the greatest effect on the adhesion. The results of study can provide some reference for the selection of bauxite clinker, which is used in different types of highway construction, and a theoretical reference for the applicability research of bauxite clinker in asphalt mixture and the improvement of skid resistance and durability of pavement.
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Prakash, P., und K. L. V. Ramana Rao. „Geomorphic Controls of the Chittamgondi Bauxite Deposit, Visakhapatnam District, Andhra Pradesh“. Journal Geological Society of India 48, Nr. 3 (01.09.1996): 257–63. http://dx.doi.org/10.17491/jgsi/1996/480302.
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Abstract Bauxite cappings occur discontinuously, along a linear stretch amidst the Eastern Ghuts comprising khondalite and charnockite groups of rocks, in the States of Andhra Pradesh and Orissa. These cappings/deposits, by virtue of their proximity to the eastern coastline of India, are christened as the East Coast Bauxite deposits. The East Coast Bauxites of Andhra Pradesh include the Anantagiri, Chintapalli, Gurtedu and Paderu groups of deposits. The Anantagiri group comprises Galikonda, Chittamgondi, Raktakonda and Kutuki deposits. The Chittamgondi bauxite deposit, charucterised by multi-directional slopes, is preserved in a sickle shaped synformal structure. Furthermore, the maximum thickness of bauxite, viz., 54 m, amongst the East Coast Bauxite deposits, investigated so far, has been recorded in it. As has already been established for other East Coast Bauxite deposits, the geomorphological setup and morphometry have played a pivotal role in the formation of the Chittamgondi bauxite deposit.
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Cui, Tao, Yang Quan Jiao und Xiao Mei Wang. „Analysis on Sedimentary Environment of Bauxite in Wuchuan-Zheng’an-Daozhen Area, Northern Guizhou“. Advanced Materials Research 616-618 (Dezember 2012): 1409–15. http://dx.doi.org/10.4028/www.scientific.net/amr.616-618.1409.
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The sedimentary environment of bauxite in Wuchuan-Zheng’an-Daozhen Area has been debated for a long time. Through research on the element B, the sedimentary characteristics of bauxite, the distribution of four different natural types of bauxite and reference paleogeographic data we concluded that bauxite in Wuchuan-Zheng’an-Daozhen Area was a typical sedimentary deposit, with a provenance mainly from south-west. Bauxite was formed in an anoxic bay, which was partly closed and open to north. The sedimentary environment shifted between lacustrine and bay environments, accompanying frequent transgression and regression cycles.
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Li, Yan, Zhao Hui Huang und Yan Gai Liu. „Study on Mineral Composition and Main Mineral Morphology of Bauxite from ZhongXiang, HuBei Province“. Key Engineering Materials 512-515 (Juni 2012): 648–51. http://dx.doi.org/10.4028/www.scientific.net/kem.512-515.648.
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In this paper, the mineral composition and main mineral morphology of bauxite were studied from ZhongXiang deposit, HuBei province. Through Electron Microscope Identification, there are two main rock types, oolitic, bean-like and aphanitic or fine crystalline structure of bauxite. The main mineral morphology is micro-crystalline or flake, crumby forms. The mineral and chemical compositions of samples were investigated by XRD, EPMA analysis tests. The EPMA results showed that Al2O3 content is 47.95% ~ 75.04%, in association with other isomorphous impurities, such as Si, Fe, Ti and Mg in varying proportions. The mineral compositions of bauxite ore are mainly aluminum, iron, silicon minerals, which totally account for from 83.01% to 86.40%. The XRD revealed that diaspore, hematite and kaolinite are the major mineral components in the bauxite ores. The bauxite from ZhongXiang deposits is a type of high diaspore bauxite, partly with clay minerals. Furthermore, the function of bauxite as a good fire-resistant material was discussed.
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Danner, Tobias, Malin Sletnes und Harald Justnes. „Alkali-reduced Bauxite Residue as Novel SCM“. Nordic Concrete Research 63, Nr. 2 (01.12.2020): 1–20. http://dx.doi.org/10.2478/ncr-2020-0015.
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Abstract Bauxite residue is a major waste stream available in large volumes globally that can cause risks to the surrounding environment (e.g. ecotoxicity) when disposed and stored by conventional methods. There is yet no large-scale application and the utilization as supplementary cementitious material might be the best way to re-use bauxite residue. The main obstacle for the utilization of bauxite residue in the construction industry is the high alkalinity. This paper presents first results of a study on alkali reduction of bauxite residue by acetic acid treatment and the potential application of this alkali reduced bauxite residue as pozzolan in cementitious binders. A process of alkali reduction is presented that can help solving waste management problems of alumina refineries by transforming bauxite residue to a less hazardous waste, while producing a reactive pozzolan and Na-acetate that can find application in the construction and infrastructure market. 90% alkalinity reduction of bauxite residue could be achieved by simply washing with diluted acetic acid. Alkali-reduced bauxite residue showed good pozzolanic reactivity regarding portlandite consumption, bound water and 28-day compressive strength of mortars with 20% replacement of OPC.
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Jafar, N., S. R. Nurhawaisyah, S. Widodo, C. A. Chalik und M. H. Wakila. „Mineralogical Study of Bauxite of Kenco Area, Landak District, West Kalimantan Province, Indonesia“. IOP Conference Series: Earth and Environmental Science 1134, Nr. 1 (01.01.2023): 012025. http://dx.doi.org/10.1088/1755-1315/1134/1/012025.
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Abstract Indonesia is a country with a tropical climate that allows for high levels of weathering. Bauxite is the result of weathering rocks that have high aluminum content, low iron content, and little quartz content. The formation of bauxite deposits is controlled by source rock which is rich in Al element, tropical climatic conditions, and geomorphological conditions that allow the formation of the accumulation of weathered source rock products. The altered silicate minerals due to weathering result in the silica element being released from the crystal bonds and some iron are released so that the aluminum element is concentrated as a residual precipitate. X-ray diffraction (XRD) analysis on 16 bauxite samples which are estimated to represent the overburden horizon, bauxite ore horizon, clay horizon, and source rock to establish the mineral composition of bauxite. Mineral groups in the overburden horizon, bauxite ore horizon, and clay horizon are alumina, iron, titanium, silicates, carbonates, sulfides, and sulfates, while mineral groups in source rock are iron, titanium, silicate, sulfide, and sulfate. The type of bauxite in the study area is gibbsite bauxite based on the dominant appearance frequency of gibbsite compared to mineral corundum as an alumina group.
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Ceuputra, David Pranasetyo, M. Khalid Syafrianto und Wahdaniah Mukhtar. „BAUXITE RESOURCE ESTIMATION IN BLOCK 2 AT PT. ANUGRAH BORNEO MARUYA PERSADA, KETAPANG REGENCY, KALIMANTAN BARAT PROVINCE“. Jurnal Teknik Sipil 24, Nr. 2 (24.08.2024): 1110. http://dx.doi.org/10.26418/jts.v24i2.68902.
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According to the Mineral Commodity Analysis and Evaluation Team of the International Mineral Information Center Development Project (1983), bauxite is an alumina ore used in industrial applications and as a primary material in aluminum production. Bauxite deposits are abundant in West Kalimantan. PT. Anugerah Borneo Maruya Persada, a mining company located in Deranuk Village, Jelai Hulu District, Ketapang Regency, focuses on bauxite extraction. Due to high market demand, the company seeks to identify new resources, necessitating an estimation of potential bauxite resources. This study evaluates the bauxite resources in Block 2 of PT. Anugrah Borneo Maruya Persada using the Area of Influence (AOI) polygon-included method. The bauxite volume is calculated by determining the area of influence and multiplying it by the deposit thickness. A test pit spacing of 50 meters and a cut-off grade of ≥35% were used to assess deposit distribution. Results show high-grade bauxite at 10 test pits, medium-grade at two pits, and low-grade at six pits, with deposits spreading from west to east. The total estimated bauxite volume in Block 2 is 66,250 m³ or 106,000 tons.
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Li, Longjiang, und Jun Liu. „Study on Calcination Characteristics of Diaspore-Kaolin Bauxite Based on Machine Vision“. Molecules 29, Nr. 16 (11.08.2024): 3813. http://dx.doi.org/10.3390/molecules29163813.
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D-K-type bauxite from Guizhou can be used as an unburned ceramic, adsorbent, and geopolymer after low-temperature calcination. It aims to solve the problem where the color of the D–K-type bauxite changes after calcination at different temperatures. Digital image processing technology was used to extract the color characteristics of bauxite images after 10 min of calcination at various temperatures. Then, we analyzed changes in the chemical composition and micromorphology of bauxite before and after calcination and investigated the correlation between the color characteristics of images and composition changes after bauxite calcination. The test results indicated that after calcining bauxite at 500 °C to 1000 °C for 10 min, more obvious dehydration and decarburization reactions occurred. The main component gradually changed from diaspore to Al2O3, the chromaticity value of the image decreased from 0.0980 to 0.0515, the saturation value increased from 0.0161 to 0.2433, and the brightness value increased from 0.5890 to 0.7177. Studies have shown that changes in bauxite color characteristics are strongly correlated with changes in composition. This is important for directing bauxite calcination based on digital image processing from engineering viewpoints.
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Yang, Zhiyong, Yunsheng Zheng, Zhijun Ma, Liang Cheng, Guangming Wang und Ying Qin. „Medium-temperature calcination and acid pressure leaching extract the Al2O3 from coal gangue: activation mechanism and kinetic analysis“. RSC Advances 14, Nr. 16 (2024): 11266–75. http://dx.doi.org/10.1039/d3ra08901k.
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Taylor, G., E. M. Truswell, R. A. Eggleton und R. Musgrave. „Cool climate bauxite“. Chemical Geology 84, Nr. 1-4 (Juli 1990): 183–84. http://dx.doi.org/10.1016/0009-2541(90)90206-m.
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Bogatyrev, B. A., V. V. Zhukov und Yu G. Tsekhovsky. „Phanerozic bauxite epochs“. Geology of Ore Deposits 51, Nr. 6 (Dezember 2009): 456–66. http://dx.doi.org/10.1134/s1075701509060038.
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