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Vieira, C. M. F., S. C. Intorne, J. Alexandre, M. G. Alves, and S. N. Monteiro. "Efeito da utilização de laterita nas propriedades físicas e mecânicas de cerâmica vermelha." Matéria (Rio de Janeiro) 12, no. 3 (2007): 446–52. http://dx.doi.org/10.1590/s1517-70762007000300004.
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Este trabalho tem por objetivo avaliar a incorporação de até 40% em peso de laterita a uma argila visando à fabricação de cerâmica vermelha. Inicialmente a laterita foi submetida a ensaios de caracterização mineralógica, química e física. Em seguida foram preparados corpos de prova por prensagem uniaxial a 20 MPa para queima em forno de laboratório a 700, 900 e 1100ºC. As propriedades físicas e mecânicas avaliadas das cerâmicas queimadas foram: retração linear, absorção de água e tensão de ruptura à flexão. A plasticidade das composições foi avaliada pelo método de Atterberg. Os resultados indicaram que a laterita contribuiu para melhorar a trabalhabilidade da argila. Com relação às propriedades de queima, foi observado que nas temperaturas de 700 e 900ºC a incorporação da laterita reduziu ligeiramente a absorção de água e a retração linear da argila. Por outro lado, a resistência mecânica da argila também foi reduzida. Já a 1100ºC, a laterita apresentou um efeito significativamente deletério nas propriedades avaliadas da argila. Por fim, os resultados indicaram que a laterita apresenta um potencial para utilização como componente de massa de cerâmica vermelha em temperaturas na ordem de 700 e 900ºC.
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Monteiro Nunes Cordeiro, Abner, Frederico Holanda Bastos, and Rubson Pinheiro Maia. "FORMAÇÕES CONCRECIONÁRIAS E ASPECTOS GEOMORFOLÓGICOS DO MACIÇO DO QUINCUNCÁ, NORDESTE DO BRASIL." Revista de Geografia 35, no. 4 (September 18, 2018): 68. http://dx.doi.org/10.51359/2238-6211.2018.238204.
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Fragmentos de laterita encontram-se distribuídos na porção setentrional do Província Borborema, constituindo feições residuais de um antigo capeamento laterítico, parcialmente dissecado, pelo atual sistema de drenagem. O presente trabalho propõe analisar as diferentes situações nas quais se apresentam as formações lateríticas, permitindo, assim, compreender a gênese dessas formas em função da evolução da própria paisagem na qual está inserida. O método empregado para o desenvolvimento deste trabalho consistiu em uma revisão bibliográfica detalhada sobre condições necessárias para o desenvolvimento de perfis lateríticos, seguido do levantamento de informações geológicas e climáticas, além da interpretação de mapas em escalas diversas e de trabalhos de reconhecimento de campo. Com base na pesquisa foi proposto um modelo laterização em parte da Província Borborema, onde condições de umidade superior às atuais, durante o Paleógeno, favoreceram à evolução de perfis de laterita in situ.
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Angulo Palma, Hugo Javier, Angel Legrá Legrá, and Alfredo Lázaro Coello Velázquez. "Efecto de la sustitución del petróleo aditivo por el carbón bituminoso en el proceso de molienda de los minerales lateríticos." Sinergia Académica 3, no. 2 (November 21, 2020): 22–31. http://dx.doi.org/10.51736/sa.v3i2.16.
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La presente investigación se desarrolló en las instalaciones del Centro de Investigaciones del Níquel ¨Capitán Alberto Fernández Montes de Oca¨, teniendo como objetivo evaluar el efecto que tiene la sustitución del petróleo aditivo por el carbón bituminoso en el proceso de molienda de las lateritas. En ella se demostró que el índice de Bond se incrementa a medida que aumenta el contenido de carbón bituminoso en la mezcla. Al compararla con la mezcla de petróleo y laterita utilizada en la industria se puede afirmar que utilizando un porcentaje inferior a 4,5 % de carbón bituminoso no se incrementa el consumo energético específico en los molinos, mientras que al utilizar el carbón bituminoso en el rango de 5,0 a 5,5 % se incrementa en 3,0 kW-h/t. Las mezclas preparadas cumplieron con las especificaciones exigidas por el ensayo de Bond, presentando un comportamiento granulométrico con predominio de las partículas gruesas, antes y después de ser sometidas a dicho procedimiento.
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Junior, Antonio Rodrigues Pantoja, and Marcelo Picanço. "CONCRETO PRODUZIDO COM AGREGADO GRAÚDO LATERÍTICO EM SANTARÉM, PARÁ." REEC - Revista Eletrônica de Engenharia Civil 16, no. 1 (June 4, 2020): 60–77. http://dx.doi.org/10.5216/reec.v16i1.61937.
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RESUMO: Avaliou-se a substituição da brita basáltica existente no concreto por material alternativo em abundância no município de Santarém-PA: a laterita. Foi avaliado o desempenho do concreto incorporado com agregado laterítico in natura em substituição parcial ao agregado graúdo de brita basáltica nos teores de 20% e 50%. Realizou-se a caracterização dos agregados graúdo e miúdo. De acordo com o método da ABCP, determinou-se o traço de referência em massa 1:1,71:3,03:0,53; confeccionou-se corpos-de-prova cilíndricos 10x20 cm utilizando 3 traços diferentes, de modo a substituir a brita basáltica pelo agregado laterítico, em 20% e 50%. Para cada traço foram quantificados a sua consistência, por meio do ensaio de abatimento do tronco de cone, resistência à compressão axial, resistência à tração por compressão diametral e módulo de elasticidade aos 28 dias. A substituição do agregado convencional de brita basáltica por agregado laterítico em seu estado natural promoveu diminuição da resistência a compressão simples, da resistência à tração por compressão diametral e do módulo de elasticidade com a inclusão do agregado laterítico na mistura. Destaca-se que acima de determinado teor de substituição o concreto torna-se inviável devido a necessidade de adicionar aditivo plastificante para manter a consistência desejada e que as duas misturas incorporadas com agregado laterítico se mostraram muito semelhantes após os 28 dias, no que tange a ganhos de resistência a compressão.
ABSTRACT: This study is about the replacement of basaltic origin crushed stone by alternative material present in the municipality of Santarém, Pará State: the laterite. The aim were to evaluate the performance of concrete incorporated with natural lateritic aggregate, replacing the of crushed stone in 20% and 50%. The first stage was characterizing the coarse and fine aggregates that made up the studied concrete. According to ABCP dosing method it was determined the mass reference trait 1: 1.71: 3.03: 0.53; bodies of 10x20 cm were made for cylindrical test, using three different strokes so that the basaltic crushed stone gradually replaced by the lateritic aggregate in proportions of 20% and 50%. For each trait its consistency was quantified by means of the tapering test, axial compression strength, diametric compression tensile strength and the modulus of elasticity at 28 days. Was observed that the replacement of the conventional aggregate basalt crushed stone for aggregate of laterite in natural state promoted a decrease in the value of simple compressive strength, diametric tensile strength and modulus of elasticity with inclusion of a larger amount of lateritic aggregate in the mixture. It is noteworthy that above a certain substitution content, the concrete becomes not feasible due to the need for a large increase in the amount of plasticizer additive to the desired consistency is maintained and the two blends incorporated with lateritic showed very similar after 28 days in terms of gains in compressive strength.
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Nguyen, Hoang Phuong Thao, Thi Hoang Ha Nguyen, and Thi Kim Anh Bui. "Sorption of heavy metals by laterite from Vinh Phuc and Hanoi, Vietnam." Journal of Vietnamese Environment 8, no. 4 (January 17, 2017): 235–39. http://dx.doi.org/10.13141/jve.vol8.no4.pp235-239.
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This study was carried out to evaluate the sorption capacity of Pb, As, Cd, Zn, and Mn by laterite from Tam Duong District (Vinh Phuc Province) and Thach That District (Hanoi City). Laterite sam- ples were exposed to different initial concentrations of heavy metals in solutions (2.5, 5.0, 10, 20, and 50 mg/l) at pH = 5.5 during 24 hours. The results demonstrated that sorption capacity of heavy metals was in the following order: Pb> As> Cd> Zn>Mn. The highest sorption capacity of Pb, As, Cd, Zn, and Mn of laterite from Tam Duong was 1553, 756, 397, 281, and 143 mg/kg, respectively and the highest removal efficiency was 94, 76, 70, 56 and 37%. The results indicated that laterite from Tam Duong District showed lower sorption capacity than that from Thach That District. The disparity sorption capacity of Pb, As, Cd, Zn, Mn between laterite from Thach That and Tam Duong was 10.3–11.6, 11.9–17.9, 11.5–13.7, 9.5–17.6, and 11.1–14.3%, respectively. Laterites from Tam Duong and Thach That are a promising environmental material which can be used in the removal of heavy metals from wastewater.
Nghiên cứu này được thực hiện nhằm đánh giá khả năng hấp phụ Pb, As, Cd, Zn, và Mn bởi laterit đá ong khu vực huyện Tam Dương (Vĩnh Phúc) và huyện Thạch Thất (Hà Nội). Mẫu đá ong được tiến hành thí nghiệm trong các dung dịch có hàm lượng kim loại nặng ban đầu khác nhau (2,5; 5,0; 10; 20 và 50 mg/l) tại pH=5,5 trong 24 giờ. Kết quả nghiên cứu cho thấy mức độ hấp phụ kim loại nặng bởi laterit đá ong lần lượt là Pb> As> Cd> Zn>Mn. Dung lượng hấp phụ Pb, As, Cd, Zn và Mn cao nhất của laterit Tam Dương lần lượt là 1553, 756, 397, 281 và 143 mg/kg và hiệu suất hấp phụ cao nhất lần lượt là 94, 76, 70, 56 và 37%. Dung lượng hấp phụ kim loại nặng của laterit huyện Tam Dương thấp hơn khu vực huyện Thạch Thất. Sự chênh lệch về dung lượng hấp phụ Pb, As, Cd, Zn và Mn giữa laterit Thạch Thất và laterit Tam Dương lần lượt là 10,3–11,6; 11,9–17,9; 11,5– 13,7; 9,5–17,6 và 11,1–14,3%. Kết quả nghiên cứu bước đầu cho thấy đá ong khu vực huyện Tam Dương và Thạch Thất là vật liệu hấp phụ tiềm năng phục vụ ứng dụng trong xử lý nước thải bị nhiễm kim loại nặng.
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Fadli, Fadli. "Hubungan Pola Penyebaran dan Ketebalan Zona Bijih Endapan Nikel Laterit dengan Topografi Permukaan Pada PT Aneka Tambang Tbk." Indonesian Journal of Earth Sciences 1, no. 1 (June 20, 2021): 10–16. http://dx.doi.org/10.52562/injoes.v1i1.18.
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Abstrak: Indonesia merupakan negara yang memiliki sumber daya nikel laterit yang berlimpah, mulai dari Sulawesi hingga ke Papua. Oleh karena itu, peneliti melakukan analisis pola sebaran dan ketebalan endapan nikel leterit untuk mendapatkan pola sebaran zona bijih dari endapan nikel laterit berdasarkan topografi permukaan. Adapun metode yang dilakukan adalah menganalisis sampel pemboran dengan X-ray spectometer, menganalisis topografi, morfologi dan membuat profil penampang antar sumbu bor untuk menganalisis pola sebaran zona bijih endapan nikel laterit. Data yang dihasilkan dari penelitian ini adalah bentuk topografi perbukitan dengan morfologi bergelombang, miring hingga melandai, dengan kemiringan lereng 20-160. Penampang endapan secara vertikal mengunakan parameter overburden dengan kadar Ni < 0.90% – > 4%. Penampang serta pola sebaran endapan nikel laterit terbagi 3 warna yaitu coklat untuk kadar Ni < 0.90%, kuning untuk kadar Ni 0,91% – 1,50%, dan hijau untuk kadar Ni > 1,51%. Berdasarkan penampang korelasi pada topografi landai, didapatkan kadar yang tinggi serta tebal dan topografi yang berbukit miring ditemukan kadar yang tinggi tetapi ketebalan yang tipis. Secara keseluruhan kadar nikel laterit berkisar 8 – 16 meter. Kata Kunci: Topografi, Nikel Laterit, Kadar, Ketebalan, Pola Penyebaran Abstract: Indonesia is a country that has abundant nickel laterite resources, from Sulawesi to Papua. Therefore, the researchers analyzed the distribution pattern and thickness of the nickel leterite deposits to obtain the distribution pattern of the ore zones of the laterite nickel deposits based on the surface topography. The method used is to analyze the drilling sample with an X-ray spectometer, analyze the topography, morphology and create a cross-sectional profile between the drill axes to analyze the distribution pattern of the laterite nickel ore deposit zone. The data generated from this study is a hilly topography with a wavy morphology, slanted, and sloping, with a slope of 20-160. The vertical cross section of the sediment uses overburden parameters with Ni content < 0.90% – > 4%. The cross-section and distribution pattern of laterite nickel deposits are divided into 3 colors, namely brown for Ni content < 0.90%, yellow for Ni content 0.91% – 1.50%, and green for Ni content > 1.51%. Based on the cross-sectional correlation on the sloping topography, it was found that high grades and thick and hilly topography found high grades but thin thicknesses. Overall, laterite nickel content ranges from 8 to 16 meters. Keywords: Topography, Nickel Laterite, Grade, Thickness, Distribution Pattern
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Paladini, Bilal Sanmartin, Rafael Cámara Artigas, and Eduardo Rodrigues Viana de Lima. "Análise do Processo de Voçorocamento e Proposta de Ordenamento Territorial no Litoral Sul da Paraíba (Brasil) (Review of the Voçorocamento and Proposed Land Use on the South Coast of Paraiba (Brazil))." Revista Brasileira de Geografia Física 5, no. 5 (January 7, 2013): 1215. http://dx.doi.org/10.26848/rbgf.v5i5.232816.
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Para se chegar a uma proposta de ordenamento territorial no sentido de minimizar os problemas decorrentes dos processos erosivos intensos existentes no litoral paraibano, foi feito um estudo sobre a gênese de duas voçorocas, buscando-se propor uma hipótese baseada nas mudanças do uso do solo, uma vez que a área sob estudo é muito sensível a esse tipo de processo erosivo devido suas características geomorfológicas, climatológicas e de uso do solo. A partir do conhecimento da gênese desses processos erosivos e através de uma cartografia de riscos naturais associados a voçorocas, foi proposto o ordenamento territorial do litoral sul da Paraíba, levando em consideração a possibilidade de criação de corredores ecológicos entre manchas de Mata Atlântica e outros tipos de vegetação nativa em áreas susceptíveis a erosão linear.Palavras-chave: Voçoroca, piping, laterita, erosão. Review of the Voçorocamento and Proposed Land Use on the South Coast of Paraiba (Brazil) ABSTRACTThe main objective of this work is to make a proposal of natural resources management with the aim of generate cartography of natural hazards linked to gullies. The final aim of the research is to create cartography of natural hazards linked to gullies processes in order to create corridors between patches of Atlantic Forest. A description of two voçorocas was executed to formulate a hypotesis aiming to explain the genesis of the erosion based on land uses changes. Finally we explained the recover and stabilitation process on the erosion carried out by the LEPAN (Laboratory of Spacial Analisis - Federal Universtity of Paraiba). Our area is very susceptible to gully processes due his geomorphology, climatology and human occupation.Keywords: Voçoroca, piping, laterite, erosion.
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Lintjewas, Lediyantje, Iwan Setiawan, and Andrie Al Kausar. "Profil Endapan Nikel Laterit di Daerah Palangga, Provinsi Sulawesi Tenggara." RISET Geologi dan Pertambangan 29, no. 1 (June 27, 2019): 91. http://dx.doi.org/10.14203/risetgeotam2019.v29.970.
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Nikel laterit adalah mineral logam hasil dari proses pelapukan dan pengkayaan mineral pada batuan ultramafik. Geologi di daerah Palangga, Provinsi Sulawesi Tenggara, disusun oleh batugamping dari Formasi Eimoko dan Formasi Langkolawa yang memiliki hubungan ketidakselarasan dengan batuan ultramafik di bawahnya sebagai pembawa endapan nikel laterit. Proses pelapukan pada batuan ultramafik menghasilkan karakter dan profil nikel laterit yang berbeda. Penelitian ini bertujuan untuk mengidentifikasi karakterisasi nikel laterit berdasarkan pada mineralogi dan profil dari Zona lateritisasi. Berdasarkan hasil penelitian diketahui bahwa jenis batuan pembawa nikel laterit di Daerah Palangga adalah harsburgit. Nikel laterit memiliki ketebalan sekitar 15 meter. Zona Limonit memiliki komposisi mineral lempung berupa kaolinit, mineral oksida berupa mineral magnetit, hematit, kromit dan mineral hidroksida berupa gutit. Kedalaman Zona Limonit yaitu sekitar 0 - 3 meter dengan kandungan Ni sekitar 0,76 – 1,78%, Fe sekitar 34,10 – 48,31%, dan SiO2 sekitar 9,42 – 18,02%. Zona Saprolit memiliki komposisi mineral silikat berupa kuarsa, garnierit, antigorit, enstatit, dan lisardit. Kedalaman Zona Saprolit sekitar 3 – 9 meter dengan kandungan Ni sekitar 1,79 – 2,98%, Fe sekitar 10,27 – 34,52%, SiO2 sekitar 22,0 – 49,63%. Batuan dasar (Bedrock) memiliki komposisi mineral silikat, antigorit, enstatit, olivin, augit dan lisardit. Kedalaman batuan dasar (bedrock) sekitar 9 – 10 meter dengan kandungan Ni sekitar 0,95 – 1,28%, Fe sekitar 7,62 – 8,29%, SiO2 sekitar 42,81 – 45,85%. Zona Saprolit merupakan Zona yang kaya akan nikel, dengan mineral penyusun berupa kuarsa, garnierit, antigorit, enstatit, dan lisardit. Nickel laterite is metal mineral formed by weathering and mineral enrichment of ultramafic rocks. Geology of Palangga area, Southeast Sulawesi Province arranged by limestone of Eimoko Formation and Langkowala Formation that have unconformity relation with ultramafic rocks as source of nickel laterite. Weathering process underwent ultramafic rocks resulted in different nickel laterite characters and their profile. The study aims to identify characterization of nickel laterite based on mineralogy and lateritization profile zones. Based on the result of study, source of nickel laterite in Palangga area is harzburgite. Nickel laterite profile has around 15 meters thick. Mineral composition of Limonite Zone is clay mineral as kaolinit, oxide mineral consisted of magnetite, hematite, chromite, and hidroksida mineral as goetite. Depth of Limonite Zone around 0 - 3 meters with Ni grade around 0,76 – 1,78%, Fe around 34,10 – 48,31%, and SiO2 around 9,42 – 18,02%. Mineral composition of Saprolite Zone is silicate mineral consist of quartz, garnierite, antigorite, enstatite, and lizardite minerals. Depth of Saprolite Zone around 3 – 9 meters with Ni grade around 1,79 – 2,98%, Fe around 10,27 – 34,52%, and SiO2 around 22,0 – 49,63%. Mineral composition of bedrock is silikat minerals consits of antigorite, enstatite, olivine, augit, and lizardite minerals. Depth of Bedrock ar ound 9 – 10 meters with grade Ni 1,28%, Fe around 7,62 – 8,29%, and SiO2 around 42,81 – 45,85%. The Saprolit Zone is a Zone that rich in nickel, with mineral composition is quartz, garnierite, antigorite, enstatite, and lizardite minerals.
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Ngadenin, Ngadenin, Kurnia Setiawan Widana, and Adhika Junara Karunianto. "Studi Keterdapatan Torium Pada Endapan Laterit Bauksit di Pulau Singkep Dalam Rangka Pengembangan Eksplorasi Torium di Wilayah Granit Jalur Timah." EKSPLORIUM 39, no. 1 (July 10, 2018): 17. http://dx.doi.org/10.17146/eksplorium.2018.39.1.4258.
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Eksplorasi torium di wilayah granit jalur timah pada lima tahun terakhir ditargetkan pada keterdapatan torium di cebakan timah primer maupun sekunder. Pulau Singkep adalah bagian dari Granit Jalur Timah, yang potensial terhadap keberadaan torium, sebagai cebakan primer maupun sekunder. Penelitian ini bertujuan untuk mengetahui karakteristik keterdapatan torium pada laterit bauksit menyangkut kadar torium dan kaitannya dengan keterdapatan mineral radioaktif dan kandungan cerium (Ce), lantanum (La), itrium (Y), dan zirkon (Zr) pada laterit bauksit. Data yang diperoleh dari penelitian ini akan digunakan sebagai bahan evaluasi untuk pengembangan eksplorasi torium pada cebakan laterit bauksit di Indonesia. Metode yang digunakan adalah pemetaan geologi, pengukuran kadar torium, dan pengambilan sampel konsentrat dulang untuk analisis mineral butir dan analisis kadar Ce, La, Y, dan Zr. Litologi yang menyusun daerah penelitian terdiri atas granit lapuk yang telah terubah menjadi laterit bauksit dengan kadar torium berkisar antara 25,9 hingga 177,8 ppm eTh. Konsentrat hasil pendulangan adalah konsentrat zirkon-ilmenit dengan kandungan mineral radioaktif terdiri dari zirkon, monasit, dan anatas. Kadar lantanum pada konsentrat zirkon-ilmenit adalah 0–412 ppm, cerium 0–80 ppm, itrium 27–82 ppm, dan zirkon 9.420–100.000 ppm. Keterdapatan torium pada endapan laterit bauksit di Pulau Singkep berhubungan erat dengan keterdapatan mineral zirkon, monasit, dan anatas. Karakterisrik keterdapatan torium pada endapan laterit bauksit mempunyai kemiripan dengan karakteristik keterdapatan torium pada cebakan timah primer dan sekunder. The thorium exploration in the last five years in the granite tin belt region is targeted at thorium availability in primary and secondary tin deposits. Singkep island is the part of granite tin belt which potential for thorium occurences either primer or secondary deposits. The purpose of this study was to determine the characteristics of thorium availability in bauxite laterite deposits concerning thorium content and its relation to the availability of radioactive minerals and cerium (Ce), lanthanum (La), Yttrium (Y), and zircon (Zr) contents on the bauxite laterite deposit. The data obtained from this study will be used as an evaluation material for the development of thorium exploration in bauxite laterite deposits in Indonesia. The methods used are geological mapping, thorium concentration measurements, and sampling of pan concentrate for mineral grain analysis and analysis of Ce, La, Y, and Zr contens. The lithology of the study area was granite that had weathered and turned into bauxite laterite deposit with thorium content ranging from 25.9 to 177.8 ppm eTh. The concentrate of the repeating result is zircon-ilmenite concentrate with radioactive mineral content composed of zircon, monazite, and anatase. La concentration on zircon-ilmenite concentrate is 0–412 ppm, Ce is 0–80 ppm, Y is 27–82 ppm and zircon is 9,420–100,000 ppm. Avaibility of thorium at the bauxite laterite deposit on Singkep Island is closely related to the zircon, monazite, and anatase minerals. Characteristics of thorium availability in the bauxite laterite deposit are similar to the thorium characteristics of the primary and secondary tin deposits.
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S, Bhaskar, Basavaraju Manu, and Sreenivasa M Y. "Bioleaching of iron from laterite soil using an isolated Acidithiobacillus ferrooxidans strain and application of leached laterite iron as Fenton’s catalyst in selective herbicide degradation." PLOS ONE 16, no. 3 (March 30, 2021): e0243444. http://dx.doi.org/10.1371/journal.pone.0243444.
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A novel isolated strain Acidithiobacillus ferrooxidans BMSNITK17 has been investigated for its bioleaching potential from lateritic soil and the results are presented. System conditions like pH, feed mineral particle size, pulp density, temperature, rotor speed influences bioleaching potential of Acidithiobcillus ferrooxidans BMSNITK17 in leaching out iron from laterite soil. Effect of sulfate addition on bioleaching efficiency is studied. The bioleached laterite iron (BLFe’s) on evaluation for its catalytic role in Fenton’s oxidation for the degradation of ametryn and dicamba exhibits 94.24% of ametryn degradation and 92.45% of dicamba degradation efficiency. Fenton’s oxidation performed well with the acidic pH 3. The study confirms the role of Acidithiobacillus ferrooxidans in leaching iron from lateritic ore and the usage of bioleached lateritic iron as catalyst in the Fenton’s Oxidation.
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Saldanha, João Darcy de Moura, and Mariana Petry Cabral. "Potes e pedras: uma gramática de monumentos megalíticos e lugares naturais na costa norte do Amapá." Revista de Arqueologia 25, no. 1 (July 1, 2012): 48–57. http://dx.doi.org/10.24885/sab.v25i1.339.
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Na costa do Amapá e da Guiana Francesa ocorreu o desenvolvimento de uma cultura pré-colonial que apresenta, como uma desuas características principais, a construção de monumentos megalíticos e a utilização de lugares naturais com formações rochosas, ambos utilizados para fns ritualísticos e/ou funerários. Embora diferentes em essência, estes tipos de sítios possuem uma estruturação similar dos depósitos, indicando que performances parecidas foram feitas em ambos os tipos de sítios, misturando elementos naturais e culturais em uma espécie de “gramática” semelhante que se utiliza de potes ceramicos e pedras de granito ou laterita na construção de significados. Aqui apresentamos uma síntese do uso destes locais durante a pré-história tardia da região, procurando entender a natureza, forma e temporalidade das deposições de artefatos. A percepção da forma como estes grupos interagiram e modifcaram a paisagem, ora de maneira bem visível, ora de forma sutil, contribui para discutirmos a construção de espaços sociais não-domésticos na Amazônia pré-colonial
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Chen, De Fang, and Lang Wu. "Experimental Research on Wetting Deformation of Laterite with Different Stress Paths." Applied Mechanics and Materials 353-356 (August 2013): 544–47. http://dx.doi.org/10.4028/www.scientific.net/amm.353-356.544.
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The Modified strain triaxial apparatus is used to reveal the deformation mechanism of humid laterite. Taking into account the impact of different factors on the laterite wet deformation, the test designs different confining pressures, different degrees of compaction, different wet partial stress levels, to analyze the multi-angle of wet deformation of laterite. Humid laterites parameters are studied in different test conditions. The relationships of principal stress differences, axial strain, bulk strain, radial strain are analyzed.
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Marzuki, Alfa Sendya Hayu, Satrio Herbirowo, Bintang Adjiantoro, Yeni Muriani Zulaida, and Efendi Mabruri. "Studi Pengaruh Paduan Cr/Mo dengan Waktu Perendaman Cryogenic Treatment terhadap Sifat Keras, Tangguh, Tahan Abrasif, dan Struktur Mikro Baja Ni berbasis Laterit." Metal Indonesia 42, no. 1 (June 30, 2020): 20. http://dx.doi.org/10.32423/jmi.2020.v42.20-27.
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Grinding ball merupakan salah satu komponen dari industri tambang dan pengolahan mineral yang mempengaruhi biaya produksi. Kebutuhan grinding ball dalam negeri saat ini masih bergantung pada produk impor. Pemilihan baja berbasis laterit karena cadangan laterit di Indonesia sangat melimpah, selain itu baja laterit sudah memiliki kandungan nikel dimana unsur paduan tersebut baik untuk meningkatkan kekerasan yang dibutuhkan pada grinding ball. Namun tingkat kekerasan baja berbasis laterit yang digunakan pada penelitian ini belum memiliki nilai yang cukup untuk digunakan sebagai material grinding ball. Oleh karena itu, pada penelitian ini dilakukan proses cryogenic treatment dengan variasi waktu perendaman 10, 60, dan 360 menit serta menggunakan perbedaan komposisi paduan Cr dan Mo kemudian dilakukan pengujian kekerasan, ketahanan aus, ketangguhan dan analisis struktur mikro. Berdasarkan hasil yang diperoleh menunjukkan bahwa kekerasan setelah perlakuan mengalami peningkatan signifikan dari 17 menjadi 33,55 HRC. Selain itu, ketahanan abrasif setelah perlakuan juga meningkat seiring dengan penambahan waktu perendaman dari 0,000603 menjadi 0,000475 mg/cm2·putaran. Peningkatan tersebut terjadi karena adanya peningkatan persentase martensit pada sampel. Nilai kekerasan dan ketahanan aus terbaik terdapat pada sampel dengan paduan CrMo pada waktu perendaman 360 menit yaitu 44,1 HRC dan 0,000475 mg/cm2·putaran. Sehingga pada penelitian ini menunjukkan bahwa waktu perendaman cryogenic treatment dan komposisi paduan Cr dan Mo berpengaruh terhadap kekerasan, ketahanan abrasif serta ketangguhan baja nikel berbasis laterit. Grinding ball is a component of the mining and mineral processing industry that affects production costs. Grinding ball needs in Indonesia still depend on imported products. Laterite-based steel is chosen because of the resource of laterite in Indonesia are very abundant, besides laterite steel has nickel content which is great for increasing the hardness that needed in grinding ball. However, the hardness of Ni laterite steel used in this study does not have enough hardness to be used as a grinding ball material. Therefore, in this study cryogenic treatment was carried out with variations in soaking time during10, 60 and 360 minutes and also using differences in the alloying composition of Cr/Mo then performed characterization of hardness, abrasive resistance, toughness and microstructure analysis. Based on the results obtained showed that hardness after treatment increases with increasing soaking time from 17 to 33,55 HRC significantly. In addition, abrasive resistance after treatment also increases with increasing soaking time from 0,000603 to 0,000475 mg/cm2.cycle. This increase occurred because of an increase in the percentage of the martensite phase in the sample. The optimum value of hardness and wear resistance is found in samples with CrMo alloy at 360 minutes soaking time, which is 44.1 HRC and 0.000475 mg/cm2·cycle. This study shows that cryogenic treatment soaking time and Cr and Mo alloy composition affect the hardness, abrasive resistance, and toughness of laterite nickel-based steel.
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Tupaz, Carmela Alen J., Yasushi Watanabe, Kenzo Sanematsu, Takuya Echigo, Carlo Arcilla, and Cherisse Ferrer. "Ni-Co Mineralization in the Intex Laterite Deposit, Mindoro, Philippines." Minerals 10, no. 7 (June 27, 2020): 579. http://dx.doi.org/10.3390/min10070579.
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The Intex laterite deposit in Mindoro, Philippines is derived from the weathering of the ultramafic rocks under a tropical climate. This study investigates the several types of serpentines and the effect of the degree of chemical weathering of ultramafic rocks and laterites on the enrichment of Ni in the deposit. The five types of serpentines are differentiated based on their textural features and Raman spectral data. Type I, type II, type III, and type IV serpentines contain a low amount of NiO (average 0.15 wt%), and their formation is linked to the previous exhumation of the ultramafic body. Conversely, type V serpentines show the highest NiO contents (average 1.42 wt%) and have the composition of serpentine-like garnierites, indicating a supergene origin. In the limonite horizon, goethite is the main ore mineral and shows high NiO contents of up to 1.68 wt%, whereas the Mn-oxyhydroxides (i.e., asbolane and lithiophorite–asbolane intermediate) display substantial amounts of CoO (up to 11.3 wt%) and NiO (up to 15.6 wt%). The Ultramafic Index of Alteration (UMIA) and Index of Lateritization (IOL) are used to characterize the different stages of weathering of rocks and laterites. The calculated index values correspond to a less advanced stage of weathering of the Intex laterites compared with the Berong laterites. The Berong deposit is a Ni-Co laterite deposit in the Philippines, which is formed from the weathering of the serpentinized peridotite. The less extreme degree of weathering of the Intex laterites indicates less advanced leaching, and thereby the re-distribution of Ni, Si, and Mg from the limonite towards the saprolite horizon may have resulted in the poor precipitation of talc-like (kerolite-pimelite) and sepiolite-like (sepiolite-falcondoite) phases in the studied saprolite horizon. Nickel in the Intex deposit has undergone supergene enrichment similar to other humid tropical laterite deposits.
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Zainuddin, Atiqah Najwa, Mazidah Mukri, Diana Che Lat, Roslizayati Rosli, and Noor Hidayu Abdul Rani. "INFLUENCE OF DIFFERENT PERCENTAGE BOILER ASH-BASED GEOPOLYMER IN LATERITE SOIL." IIUM Engineering Journal 22, no. 2 (July 4, 2021): 67–82. http://dx.doi.org/10.31436/iiumej.v22i2.1589.
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The waste generation of palm oil boiler ash has been one of its big problems as it is less used and deposited in landfills as a by-product. Geopolymer is a new green technology that has been intensively studied in concrete applications. However, few studies on geopolymers have been conducted in soil applications. Thus, this study investigated the influence of palm oil boiler ash-based geopolymer in laterite soil strength. Different percentages, 5, 10, 15, and 20% of geopolymer mixtures, were added to laterite soil. The process of producing a geopolymer binder was performed by sieving boiler ash (150 µm), then mixing with sodium hydroxide (NaOH) and sodium silicate (Na2SiO3) as an alkaline activator at a ratio of 1:2. This material effectiveness was tested through compaction test using a standard proctor, unconfined compressive strength, and the scanning electron microscope (SEM). 15% of geopolymer in laterite soil indicated the best-mixed design with a maximum dry density of 2.23 Mg/m3 with a moisture content of 13.58%. The unconfined compressive strength test at curing times of zero, seven, and twenty-eight days on the LS-15.0 GPOBA sample, show a slightly increased strength of 47, 58, and 76 kPa, respectively. The SEM images proved that the geopolymer gel's development stabilized the soil structure from a loose structure to a denser soil structure. This study aims to investigate the influence of geopolymer in laterite soil. Boiler ash as an alternative material in geotechnical applications was studied to understand and develop new green alternative materials to sustain the environment from industrial waste and to enhance laterite soil properties. ABSTRAK: Abu kelapa sawit adalah salah satu sisa utama yang terhasil dari industri kelapa sawit tetapi penggunaannya kurang dimanfaatkan dan dibuang ke tempat pembuangan sampah. Teknologi hijau baru yang dikenali sebagai geopolimer telah dikaji secara intensif dengan kekuatan konkrit tetapi hanya sedikit kajian telah dibuat dalam penggunaan tanah. Tujuan kajian ini adalah bagi mengesan geopolimer berasaskan abu kelapa sawit terhadap kekuatan tanah laterit. Peratusan campuran geopolimer yang berbeza (0, 5, 10, 15 dan 20%) dicampur pada tanah laterit. Bagi menghasilkan geopolimer, saiz 150 ?m abu kelapa sawit disintesis dengan kombinasi bahan kimia natrium hidroksida (NaOH) dan natrium silikat (Na2SiO3) pada nisbah 1:2 bagi semua campuran sebagai pengaktif alkali. Ujian terhadap keberkesanan bahan adalah melalui proses ujian pemampatan menggunakan proktor standard, kekuatan pemampatan tidak terbatas, dan Pengimbas Mikroskop Elektron (SEM). Berdasarkan dapatan ujian pemadatan, 15% geopolimer di tanah laterit menunjukkan campuran terbaik dengan memberikan kepadatan pengeringan maksimum 2.23 Mg/m3 pada kelembapan 13.58%. Ujian kekuatan mampatan tidak terbatas pada masa pempolimeran sebanyak 0, 7 dan 28 hari diuji pada sampel LS-15.0GPOBA bagi menguji kekuatan campuran. Dapatan menunjukkan kekuatan geopolimer sedikit meningkat pada 47, 58 dan 76, masing-masing. Imej SEM membuktikan pengembangan gel geopolimer menstabilkan struktur tanah daripada struktur lopong kepada struktur tanah padat. Oleh itu, abu kelapa sawit berasaskan geopolimer dan tanah laterit berpotensi sebagai alternatif bagi merawat tanah dalam aplikasi geoteknik dan berpotensi mengurangkan kadar kebolehtelapan.
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Pho, Nguyen Van, Pham Tich Xuan, and Pham Thanh Dang. "Occurrence of supergene nickel ores in the Ha Tri Massive, Hoa An District, Cao Bang Province." VIETNAM JOURNAL OF EARTH SCIENCES 40, no. 2 (January 19, 2018): 154–65. http://dx.doi.org/10.15625/0866-7187/40/2/11676.
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Nickel (Ni) laterites are regolith materials derived from ultramafic rocks and play an important role in the world's Ni production. Ni-laterite deposits are the supergene enrichment of Ni formed from the intense chemical and mechanical weathering of ultramafic parental rocks. In Vietnam, the weathering profile containing Ni laterite was first discovered in the Ha Tri massive (Cao Bang). This profile develops on the Ha Tri serpentinized peridotite rocks classified to the Cao Bang mafic-ultramafic complex (North Vietnam) and exhibits thick weathered zone (10 - 15m). This work carried out a detailed study of the weathering profile at the center of Ha Tri massive. Samples from different horizons of the profile were collected and analyzed in detail by XRF, XRD and SEM-EDX methods to establish the relationship between the Ni-rich supergene products and the parental peridotites (lherzolite) rocks in Ha Tri massive. The results show that the saprolite horizon is most Ni-rich in the weathering profile in Ha Tri. In this horizon, Ni-silicate minerals of garnierite group such as pimelite, nepouite and other Mg-Ni silicates have been found. The appearance of minerals of garnierite group is due to the exchange of Mg by Ni during weathering of peridotite minerals, especially olivine, which leads to the enrichment of the supergene Ni. The occurrence of Ni silicates suggests the existence of the supergene Ni ore in the weathering profile of the Ha Tri massive.References Bosio N.J., Hurst J.V., Smith R.L., 1975. Nickelliferousnontronite, a 15 Å garnierite, at Niquelandia, Goias Brazil. Clays Clay Miner., 23, 400-403. Brand N.W., Butt C.R.M., Elias M., 1998. Nickel Laterites: Classification and features. AGSO Journal of Australian Geology & Geophysics, 17(4), 81-88. Bricker O.P., Nesbitt H.W. and Gunter W.D., 1973. The stability of talc. American Mineralogist, 58, 64-72. Brindley G.W. and Hang P.T., 1973. The nature of garnierites. Structures, chemical composition and color characteristics. Clay and Clay Minerals, 21, 27-40. Brindley G.W. and Maksimovic Z., 1974. The nature and nomenclature of hydrous nickel-containing silicates. Clay Minerals, 10, 271-277. Brindley G.W. and Wan H.M., 1975. Composition structures and thermal behavior of nickel containing minerals in thelizardite-ne´pouite series. American Mineralogist, 60, 863-871. Brindley G.W., Bish D.L. and Wan H.M., 1979. Compositions, structures and properties of nickel containing minerals in the kerolite-pimelite series. American Mineralogist, 64, 615-625. Cluzel D. and Vigier B., 2008. Syntectonic mobility of supergene nickel ores from New Caledonia (Southwest Pacific). Evidence from faulted regolith and garnierite veins. Resource Geology, 58, 161-170. Colin F., Nahon D., Trescases J.J., Melfi A.J., 1990. Lateritic weathering of pyroxenites at Niquelandia, Goais, Brazil: The supergene behavior ofnickel: Economic Geology, 85, 1010-1023. Das S.K., Sahoo R.K., Muralidhar J., Nayak B.K., 1999. Mineralogy and geochemistry of profilesthrough lateritic nickel deposits at Kansa,Sukinda, Orissa. Joural of Geoogical. SocietyIndia, 53, 649-668. Decarreau A., Colin F., Herbillon A., Manceau A., Nahon D., Paquet H., Trauth-Badaud D.,Trescases J.J., 1987. Domain segregation in NiFe-Mg-Smectites. Clay Minerals, 35, 1-10. Freyssinet P., Butt C.R.M. and Morris R.C., 2005. Oreforming processes related to lateritic weathering. Economic Geology, 100th aniversary volume, 681-722.Garnier J., Quantin C., Martins E.S., Becquer T., 2006. Solid speciation and availability of chromium in ultramafic soils from Niquelandia, Brazil. Journal of Geochemical Exploration, 88, 206-209. Garnier J., Quantin C., Guimarães E., Becquer T., 2008. Can chromite weathering be a source of Cr in soils? Mineralogy Magazine, 72, 49-53. Gleeson S.A., Butt C.R. and Elias M., 2003. Nickel laterites: A review. SEG Newsletter, 54, 11-18. Gleeson S.A., Butt C.R., Wlias M., 2003. Nickellaterites: a review. SEG Newsletter, Society of Economic Geology, 54. Available from www.segweb.org. Golightly J.P., 1981. Nickeliferous laterite deposits. Economic Geology, 75th Anniversary volume, 710-735. Golightly J.P., 2010. Progress in understanding the evolution of nickel laterite. Society of Economic Geology, In Special Publication, 15, 451-485. Manceau A. and Calas G., 1985. Heterogeneous distribution of nickel in hydrous silicates from New Caledonia ore deposits. American Mineralogist, 70, 549-558. Nguyen Van Pho, 2013. Tropic weathering in Vietnam (in Vietnamese). Pubisher Science and Technology, 365p.Ngo Xuan Thanh, Tran Thanh Hai, Nguyen Hoang, Vu Quang Lan, S. Kwon, Tetsumaru Itaya, M. Santosh, 2014. Backarc mafic-ultramafic magmatism in Northeastern Vietnam and its regional tectonic significance. Journal of Asian Earth Sciences, 90, 45-60.Pelletier B., 1983. Localisation du nickel dans les minerais ‘‘garnieritiques’’ de Nouvelle-Caledonie. Sciences Ge´ologique: Me´moires, 73, 173-183.Pelletier B., 1996. Serpentines in nickel silicate ores from New Caledonia. In Grimsey E.J., and Neuss I. (eds): Nickel ’96, Australasian Institute of Miningand Metallurgy, Melbourne, Publication Series 6(9), 197-205. Proenza J.A., Lewis J.F., Galı´ S., Tauler E., Labrador M., Melgarejo J.C., Longo F. and Bloise G., 2008. Garnierite mineralization from Falcondo Ni-laterite deposit (Dominican Republic). Macla, 9, 197-198. Soler J.M., Cama J., Galı´ S., Mele´ndez W., Ramı´rez, A., andEstanga, J., 2008. Composition and dissolution kinetics ofgarnierite from the Loma de Hierro Ni-laterite deposit,Venezuela. Chemical Geology, 249, 191-202. Springer G., 1974. Compositional and structural variations ingarnierites. The Canadian Mineralogist, 12, 381-388. Springer G., 1976. Falcondoite, nickel analogue of sepiolite. The Canadian Mineralogist, 14, 407-409.Svetlitskaya T.V., Tolstykh N.D., Izokh A.E., Phuong Ngo Thi, 2015. PGE geochemical constraints on the origin of the Ni-Cu-PGE sulfide mineralization in the Suoi Cun intrusion, Cao Bang province, Northeastern Vietnam. Miner Petrol, 109, 161-180.Tran Trong Hoa, Izokh A.E., Polyakov G.V., Borisenko A.S., Tran Tuan Anh, Balykin P.A., Ngo Thi Phuong, Rudnev S.N., Vu Van Van, Bui An Nien, 2008. Permo-Triassic magmatism and metallogeny of Northern Vietnam in relation to the Emeishan plume. Russ. Geol. Geophys., 49, 480-491.Trescases J.J., 1975. L'évolution supergene des roches ultrabasiques en zone tropicale: Formation de gisements nikelifères de Nouvelle Caledonie. Editions ORSTOM, Paris, 259p.Tri T.V., Khuc V. (eds), 2011. Geology and Earth Resources of Vietnam. Publishing House for Science and Technology, 645p (in English). Villanova-de-Benavent C., Proenza J.A., GalíS., Tauler E., Lewis J.F. and Longo F., 2011. Talc- and serpentine-like ‘‘garnierites’’ in the Falcondo Ni-laterite deposit, Dominican Republic. ‘Let’s talk ore deposits’, 11th Biennial Meeting SGA 2011, Antofagasta, Chile, 3p.Wells M.A., 2003. Goronickel laterite deposit. New Caledonia. CRC LEME, p.3.
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Economou-Eliopoulos, Maria, Magdalena Laskou, Demetrios Eliopoulos, Ifigeneia Megremi, Sofia Kalatha, and George Eliopoulos. "Origin of Critical Metals in Fe–Ni Laterites from the Balkan Peninsula: Opportunities and Environmental Risk." Minerals 11, no. 9 (September 16, 2021): 1009. http://dx.doi.org/10.3390/min11091009.
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As the global energy sector is expected to experience a gradual shift towards renewable energy sources, access to special metals in known resources is of growing concern within the EU and at a worldwide scale. This is a review on the Fe–Ni ± Co-laterite deposits in the Balkan Peninsula, which are characterized by multistage weathering/redeposition and intense tectonic activities. The ICP-MS analyses of those laterites indicated that they are major natural sources of Ni and Co, with ore grading from 0.21 to 3.5 wt% Ni and 0.03 to 0.31 wt% Co, as well as a significant Sc content (average 55 mg/kg). The SEM-EDS analyses revealed that fine Fe-, Ni-, Co-, and Mn-(hydr)oxides are dominant host minerals and that the enrichment in these elements is probably controlled by the post-formation evolution of initial ore redeposition. The paucity of rare earth element (REE) within the typical Fe–Ni laterite ore and the preferential occurrence of Co (up to 0.31 wt%), REE content (up to 6000 mg/kg ΣREE), and REE-minerals along with Ni, Co, and Mn (asbolane and silicates) towards the lowermost part of the Lokris (C. Greece) laterite ore suggest that their deposition is controlled by epigenetic processes. The platinum-group element (PGE) content in those Fe–Ni laterites, reaching up to 88 μg/kg Pt and 26 μg/kg Pd (up to 186 μg/kg Pd in one sample), which is higher than those in the majority of chromite deposits associated with ophiolites, may indicate important weathering and PGE supergene accumulation. Therefore, the mineralogical and geochemical features of Fe–Ni laterites from the Balkan Peninsula provide evidence for potential sources of certain critical metals and insights to suitable processing and metallurgical methods. In addition, the contamination of soil by heavy metals and irrigation groundwater by toxic Cr(VI), coupled with relatively high Cr(VI) concentrations in water leachates for laterite samples, altered ultramafic rocks and soils neighboring the mining areas and point to a potential human health risk and call for integrated water–soil–plant investigations in the basins surrounding laterite mines.
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Putzolu, F., L. Santoro, C. Porto, N. Mondillo, M. Machado, B. Saar De Almeida, A. Bastos, and R. Herrington. "The Influence of the Magmatic to Postmagmatic Evolution of the Parent Rock on the Co Deportment in Lateritic Systems: The Example of the Santa Fé Ni-Co Deposit (Brazil)." Economic Geology 116, no. 4 (June 1, 2021): 837–61. http://dx.doi.org/10.5382/econgeo.4819.
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Abstract The Santa Fé Ni-Co deposit is a major undeveloped lateritic deposit located in the Goiás State of Central Brazil. The deposit comprises two properties that together have indicated resources of 35.7 million tonnes (Mt), grading 1.14% Ni and 0.083% Co, and inferred resources of 104.3 Mt at 1.03% Ni and 0.054% Co. The laterite was derived from Late Cretaceous alkaline ultramafic lithologies that experienced an initial silicification from Eocene to Oligocene, followed by lateritization and partial reworking in Miocene-Pliocene. The deposit is characterized both by oxide- and phyllosilicate-dominated ore zones. In the former, Ni- and Co-bearing hematite and goethite dominate the supergene mineralogical assemblage, while ore-bearing Mn oxyhydroxides occur as minor components. In the phyllosilicate-dominated horizons the major Ni-carrying phase is chlorite. Multivariate statistical analyses (factor analysis and principal components analysis) conducted on the drill core assay database (bulk-rock chemical analyses) showed that significant differences exist between Ni and Co distributions. The Ni distribution is not controlled by any clear geochemical correlation. This is because the highest Ni concentrations have been measured in the ferruginous and in the ochre saprolite zones, where Ni-bearing minerals (chlorite and goethite) are mostly associated with reworked material and only in a limited way, with zones affected by in situ ferrugination. Cobalt has an atypical statistical distribution at Santa Fé if compared with other laterites, correlated not only with Mn but also with Cr in the majority of the laterite facies. From microchemical analyses on several potential Co-bearing minerals, it was found that the Co-Cr association is related to elevated Co contents in residual spinels, representing unweathered phases of the original parent rock now included in the laterite. This element distribution is atypical for Ni-Co laterite deposits, where Co is normally associated with Mn in supergene oxyhydroxides. In the case of the Santa Fé laterite, the Co concentration in spinels is likely related to magmatic and postmagmatic processes that affected the original parent rock before lateritization, specifically (1) orthomagmatic enrichment of Co in chromite, due to its high affinity to spinels in alkaline melts, and (2) trace elements (i.e., Co, Mn, Ni, and Zn) redistribution during the hydrothermal alteration of chromite into ferritchromite. The Santa Fé deposit represents a good example of how the prelateritic evolution of a parent rock strongly affects the efficiency of Co mobilization and enrichment during supergene alteration. Based on the interpretation of metallurgical test work, a fraction of total Co between 20 and 50% is locked in spinels.
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Santos, Pabllo Henrique Costa dos, Marcondes Lima da Costa, and Alessandro Sabá Leite. "The Piriá aluminous lateritic profile: mineralogy, geochemistry and parent rock." Brazilian Journal of Geology 46, no. 4 (December 2016): 617–36. http://dx.doi.org/10.1590/2317-4889201620160101.
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ABSTRACT: Relatively small aluminous lateritic deposits are abundant in the northeast and northwest parts of the Pará and Maranhão states, respectively. Most of them hosts aluminum phosphate mineralization forming hills and plateaus that stand out in the topography of the undulating plains of this region. The Piriá ridge is one of those topographic features, covered by lateritic iron crusts that have been studied in the 1970s as part of iron ore exploration campaigns and recently for phosphates prospection. This study improves the knowledge about the evolution of the lateritic Piriá deposit and demonstrates its relationship with the most evolved laterites of the Amazon, known as mature laterites, which formed major ore deposits during the Paleogene. Samples of a 17 meter-deep borehole were investigated through mineralogical (X-ray diffraction -XRD, optical and electron microscopy) and chemical methods (inductively coupled plasma mass spectrometry - ICP-MS, inductively coupled plasma optical emission spectrometry - ICP-OES and X-ray fluorescence - XRF). The studied lateritic profile comprises a clay bauxitic horizon overlaid by an aluminous iron crust. Upwardly continuous dissolution of kaolinite occurs with the formation of gibbsite, as the result of intensive leaching, resulting in a higher Al2O3 content in the crust. The continuous formation of hematite from goethite resulted from the transition to more arid conditions. Anatase is a newly formed mineral (100-400 nm crystallites), showing a gradual increase, following the increase in TiO2 content, which is high and indicative of a mafic parent rock, confirmed by the Ti × Zr dispersion pattern. Prominent zoning in the lateritic profile is characterized by the mineralization in bauxite and augelite and abrupt chemical transition between the horizons, marked by a decrease in Si and increase in Fe content from the bottom to the top of the profile. These features are compatible and indicative of mature laterites formed in Amazon during the Paleogene.
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Otto, Andrew, Robert Tumwesige, and Alemayehu Ayele Endale. "Assessment of Properties of Lateritic Gravel with a View to Enhancing Sustainable Use: A Case Study." Transportation Research Record: Journal of the Transportation Research Board 2672, no. 52 (April 30, 2018): 78–85. http://dx.doi.org/10.1177/0361198118767416.
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A number of authors have reported several properties of laterite that are not exhibited by other kinds of weathered tropical soils. Most of these properties are attributed to the presence of hydrated oxides of iron and aluminum. The combination of hydrated oxides is referred to as sesquioxides. It has been reported that the strength of soils that contain sesquioxides, such as laterite, increases due to development of self-cementation that occurs on repeated cycles of soaking and drying. The primary objective of this study was to explore the behavior of lateritic gravel under various conditions to develop methods for more beneficial and sustainable use. The scope of this study was a laboratory-based assessment of lateritic gravel obtained from a major source that supplies many construction sites in Kampala City, Uganda. The strength of the gravel was assessed on soaking after initial drying, after stabilization with lime, on drying after initial soaking, and after repeated cycles of soaking and drying. The results showed that for this particular lateritic gravel, the strength was highest when stabilized with lime. The strength development after cycles of soaking and drying was negligible; in fact, there was a reduction in strength. However, at moisture content below its optimum moisture content, the strength developed by the gravel was sufficient for use as base course or sub-base at various traffic levels provided certain measures are taken. Thus, repeated cycles of soaking and drying for this lateritic gravel may in fact be detrimental in the short term.
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Chu, Fan, Ying Jun Zhang, Jiang Shen, and Xue Feng Yang. "Application of Wireless Sensor Network in Shipping Laterite Nickel Ore Moisture Content Monitoring." Applied Mechanics and Materials 336-338 (July 2013): 204–9. http://dx.doi.org/10.4028/www.scientific.net/amm.336-338.204.
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This paper applies wireless sensor network to the shipping laterite nickel ore moisture content monitoring, and design a set of real-time monitoring of lateritic nickel ore moisture content monitoring system in the process of actual transportation, and formulate a specific implementation plan. According to the structure of laterite nickel ore bulk carriers and the characteristics of the wireless sensor network, this paper also solve the design and layout problems of wireless sensor nodes, the problems of energy saving and data transmission from the inside cabin to the outside, etc. In addition, the system has strong portability, and can be used for monitoring in other related fields.
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Akerele, Adebimpe Omorinsola, Irewolede Aina Ijaola, and Olatunbosun Hezekiel Omolayo. "Effects of Synthetic Foam on the Properties of Stabilized Lateritic Bricks." Journal of Engineering, Project, and Production Management 11, no. 1 (January 1, 2021): 61–69. http://dx.doi.org/10.2478/jeppm-2021-0007.
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AbstractManaging the production costs of construction projects is crucial especially in the aspect of material management. The use of lightweight materials reduces the dead load in structures, thus the reduction in the use of reinforcement and concrete in the foundation. To this end, this study examined the effect of synthetic foam on the properties of stabilized lateritic brick with a view to producing lightweight stabilized laterite brick for use on weak soils with low bearing capacity. Laboratory tests were conducted on the bricks produced to determine the density, compressive strength, and water absorption properties at 7, 14, 21, and 28 days. Preformed foam using synthetic foaming agent was used at 0%, 25%, 50%, 75% and 100% to replace the water in the experiment. One hundred twenty samples of stabilized foamed lateritic bricks were produced at a mixed ratio of 1:4 (cement: laterite) using a 0.6 water/cement ratio. The result showed that the bricks at all percentages of foam content meet up with the minimum requirement of compressive strength of 1.6N/mm2, 2.0N/mm2 and 3.5N/mm2 recommended by the Nigerian Building code, Nigerian Building and Road Research Institute, and the third class brick of the BS 3921:1985 respectively. The water absorption is within the limits of bricks specified in standards as 15%. The highest compressive strength was recorded at 25% foam inclusion (4.839N/mm2) on 28th day hence concluding that foaming agent stabilizes the characteristics strength of laterite bricks and also reduces its density.
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Pereira-De-Oliveira, Luiz, Lucio Macedo, José Neto, Dellane Santos, and Hugo Silva. "Viability of lateritic soil as alkaline activated precursor." MATEC Web of Conferences 274 (2019): 01004. http://dx.doi.org/10.1051/matecconf/201927401004.
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This study investigates the disposal of lateritic soil available in the state of Maranhao, Brazil, to be used as a natural precursor of alkaline activated material. Lateritic soils are formed in the tropics through weathering processes that favour the formation of iron, aluminium and may contain a large amount of quartz and kaolinite. The quality of laterite for this application may vary significantly depending on both geographic location and depth of a quarry. The identification of quarry locals was carried out in this work, together with a disposal volume estimation considering economic issues about exploration techniques. A comparison of the chemical composition of the lateritic soil of the state of Maranhao with those related in the literature is used to outline the feasibility of using this natural material as precursor of alkaline activated cements. It is concluded that the lateritic soil availability, as well as their characteristics, can enable the development of alkaline activated materials as a future local building material and environmentally friendly.
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O.A, Fadele,, and Ata, O.J. "Stabilising Potential of Sawdust Lignin based Extracts in Compressed Lateritic Bricks." Civil Engineering Dimension 20, no. 1 (April 7, 2018): 16. http://dx.doi.org/10.9744/ced.20.1.16-20.
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Lignocellulosic materials are abundant in nature, rich in some functional groups, considered less harmful to human health and the environment.The resulting waste may be recycled for other beneficial uses. Lignin is known to be a natural binder in lignocellulosic materials and several studies have confirmed it has binding ability with soil particles. This paper studied its stabilising potential in compressed lateritic bricks, especially its effects on density and compressive strength properties of the bricks. Lignin additives extracted from sawdust were used to stabilise laterite, while the bricks were moulded with the UNIFE ram, a type of the CINVA ram. The laterite was stabilised at 4%, 8% and 12%, while cement stabilised samples and 0% (unstabilised laterite) samples prepared accordingly were used as controls. The results showed that the LBAs contributed to the strength gained by the bricks at 3, 7, 14 and 28 days air curing, while the bricks samples were categorised as high density.
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Adeola, Adewole John, and Emmanuel Tamunobelema Tubonemi. "Mineralogical and Geochemical Trends in the Residual Soils above Basement Rocks in Ore Area, Southwestern Nigeria." Journal of Geography and Geology 9, no. 3 (August 30, 2017): 42. http://dx.doi.org/10.5539/jgg.v9n3p42.
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Residual clays and laterite of economic values often occur within weathering profiles above basement rocks in tropical regions due to supergene enrichment and leaching of liable components. Previous studies in Ore area mainly on geochemistry of the basement rocks with scanty information on the weathered profiles. This study was carried out to determine the compositional characteristics of the basement rocks, the geochemical trends within the profiles above the parent rocks and the evaluation of their economic potentials.Petrographic study was carried out on thin sections of the rock samples. Elemental compositions of the rocks, clay, laterite, and top-soil were determined using Inductively Coupled Plasma-Mass Spectrometer (ICP-MS). Clay mineralogy was determined using X-ray Diffraction (XRD) analysis. Chemical index of Alterations (CIA) was calculated from geochemical data.Weathering of granite and banded gneiss in Ore resulted in the formation of soil layer, which ranged 0-0.5m, laterite 1.2-3m and clayey zone 2.9-3.0m. Quartz, plagioclase feldspars, microcline, biotite and hornblende were the essential minerals in the parent rocks. Granite and banded gneiss is high SiO2 (>65%) but low in MgO (<2.0%) and CaO (<4.0%). Kaolinite (60-80%), goethite (3-12%) and microcline (4-10%) were the dominant minerals in the XRD of the weathering profiles. Traces of illite were present only in granite. The CIA was generally > 85 indicating advanced state of weathering producing lateritic soil. The lateritic profiles over granite and banded gneiss of Ore area varied with the composition of the parent rocks. The clay layer has economic potential for ceramics, fertilizer and structural wares.
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Chen, Song, Shu Qiang Guo, Yu Ling Xu, Lan Jiang, and Wei Zhong Ding. "Research on Selective Reduction of Laterite Nickel Ore by CO2/H2 Mixed Gas." Advanced Materials Research 1025-1026 (September 2014): 814–19. http://dx.doi.org/10.4028/www.scientific.net/amr.1025-1026.814.
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In this paper, thermodynamic analysis on reduction of lateritic nickel ore by CO2/H2 mixed gas was performed based on activity theory. Effects of CO2/H2 ratio and temperature on selective reduction of laterite ore were investigated. The calculation result shows that the metallization of Fe and Ni could be promoted by each other because of the variation of the Fe and Ni activity, which accounts for the inescapability of Fe metallization. When laterite nickel ore was reduced by mixed gas with a CO2/H2 ratio of 9/1 and a gas flow of 100mL/min at 800°C for 1h, a product with a Ni metallization rate over 95% and a Ni/Fe ratio as much as 2.6 was prepared.
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Pate, J. S., W. H. Verboom, and P. D. Galloway. "Co-occurrence of Proteaceae, laterite and related oligotrophic soils: coincidental associations or causative inter-relationships?" Australian Journal of Botany 49, no. 5 (2001): 529. http://dx.doi.org/10.1071/bt00086.
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This communication presents the hypothesis that certain Australian lateritic and related oligotrophic soils may have been partly derived biotically from soluble iron-rich complexes generated following secretion of low-molecular weight organic acids by phosphate-absorbing specialised proteoid (cluster) roots of proteaceous plants. Subsequent precipitation of the iron is then pictured as occurring onto the oxide rinds of developing laterite after consumption of the organic components of the complexes by soil bacteria. The hypothesis is f irst examined in relation to current theories of origins of laterites and the extent of the coincidences worldwide in past and present times between Proteaceae and oligotrophic soil types of lateritic character. The paper then provides more definitive lines of evidence supporting the hypothesis, based largely on recent studies by the authors in south-western Western Australia. This relates to (a) cases of definitive association in habitats rich in Proteaceae between zones of root proliferation and ferricrete layers in lateritic soils, (b) proximity in soil profiles between ferric deposits and current and ancestral root channels, (c) the recovery of citrate-consuming bacteria from soil profiles and specifically from ferricrete rinds and horizons accumulating sesquioxide organic matter and (d) distribution of iron and phosphorus within plant and soil profile components consistent with ferricrete rinds being generated by rhizosphere-mediated interactions of plants and microbes under conditions of severely limited availability of phosphorus. The mode of functioning of proteoid root clusters is then discussed, especially in relation to exudation of organic acid anions, uptake of phosphorus and the subsequent fate of organic anions and their metal ion complexes in the system. An empirically based scheme is presented indicating flow profiles for phosphorus and iron between soil, ferricrete rinds and bacterial and plant components. We then discuss possible carbon costs to proteaceous plant partners when accessing phosphorus under the nutrient-impoverished conditions typical of heathlands and open woodlands of Mediterranean-type ecosystems of Western Australia. The paper concludes with a critical overview of the hypothesis, particularly its implications regarding possible higher plant: microbial influences shaping soil and landscape evolution in the regions involved.
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K.A., Sreejith, Sreekumar V.B., Prashob P., Nita S., Prejith M.P., and Sanil M.S. "A checklist of angiosperm flora of low elevation lateritic hills of northern Kerala, India." Journal of Threatened Taxa 12, no. 9 (June 26, 2020): 16077–98. http://dx.doi.org/10.11609/jott.4912.12.9.16077-16098.
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An inventory to prepare the checklist of angiosperm species in the lateritic hillocks of northern Kerala was conducted in five sampling sites during April 2013–March 2015. In total, we recorded 364 genera with 535 species, of which 334 are native and 201 are non-native. Native species were represented in 102 families, namely, Poaceae (28), Fabaceae (25), Acanthaceae (22), Rubiaceae (17) Euphorbiaceae (14), Commelinaceae (11), Phyllanthaceae (7), etc., whereas, non-native species were represented in 99 families. Among the native species herbs are the predominant habit with 147 species (44%). Out of the 72 endemic species, three taxa namely, Syzygium travancoricum, Santalum album and Hopea ponga are red listed species documented from the study area. Twenty-seven invasive species were also recorded and major threats to the laterite ecosystems are by Lantana camara, Mikania micrantha, Pennisetum polystachyon, Ipomoea spp., and Senna spp. Most part of the laterite has been converted to plantations, building sites and mining sites. The indiscriminate mining for laterite, soil and demolishing the hillocks have severely threatened the very existence of the flora.
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Zang, Weisheng, William S. Fyfe, and Robert L. Barnett. "A silver-palladium alloy from the Bahia lateritic gold deposit, Carajas, Brazil." Mineralogical Magazine 56, no. 382 (March 1992): 47–51. http://dx.doi.org/10.1180/minmag.1992.056.382.06.
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AbstractA silver-palladium alloy with structural formula close to AgPd has been found in laterite from the Bahia lateritic gold deposit. The alloy occurs in a void of an iron oxide nodule, associated with goethite and hematite. The angular shape and protuberances of the alloy grains suggest crystal growth in a lateritic environment, indicating that the alloy is a secondary mineral precipitated during lateritisation. The oxidation of sulphides of the parent rocks probably favoured the migration of palladium and silver as transient thiosulphate and sulphite complexes. Destruction of the thiosulphate and sulphite ligands could result in precipitation of both palladium and silver as an alloy. Eh-pH phase diagrams for Pd-H2O-C1 and Ag-H2O-C1 systems show that both palladium and silver are stable in lateritic environments under lower redox potentials. Such an environment may exist at the top of the ferruginous zone due to the abundant organic matter near the surface.
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Astuti, Widi, Fika Rofiek Mufakhir, Fajar Nurjaman, Slamet Sumardi, Ulin Herlina, Fathan Bahfie, and Himawan Tri Bayu Murti Petrus. "Pengaruh Karakteristik Bijih pada Ekstraksi Nikel dari Bijih Limonit Indonesia menggunakan Pelindian Atmosferik." Metal Indonesia 43, no. 1 (June 30, 2021): 9. http://dx.doi.org/10.32423/jmi.2021.v43.9-16.
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AbstrakKebutuhan ekstraksi nikel dari bijih nikel laterit khususnya jenis bijih limonit dengan kadar nikel yang rendah sangat diperlukan karena kebutuhan nikel yang terus meningkat dengan adanya pengembangan kendaraan bermotor listrik berbasis baterai. Jenis dan karakteristik bijih laterit yang berbeda akan memberikan pengaruh pada hasil ekstraksi nikel. Pada penelitian ini dilakukan ekstraksi nikel dari bijih laterit jenis limonit yang berasal dari Pulau Halmahera (LH)) dan Pulau Sulawesi (LS) menggunakan pelindian atmosferik. Asam sulfat digunakan sebagai agen pelindian. Penelitian dilakukan untuk mengetahui pengaruh karakteristik bijih limonit (LH dan LS) pada berbagai variabel pelindian yaitu suhu (30oC, 50oC dan 80oC), konsentrasi asam sulfat (0,5M; 1M; dan 2M), waktu pelindian (15, 30, 60, 120, dan 240 menit), serta rasio bijih terhadap reagen pelindian (5, 10, dan 20% w/v) terhadap ekstraksi nikel dari bijih limonit. Hasil penelitian menunjukkan bahwa karakteristik bijih laterit sangat berpengaruh pada hasil pelindian dan persen rekoveri nikel. Nikel dari bijih LH yaitu jenis limonit dari Pulau Halmahera dapat diekstrak secara maksimal (100%) pada konsentrasi asam sulfat 0,5M, suhu 80oC, rasio bijih/larutan asam sulfat 10%, dan waktu pelindian 2 jam. Sedangkan persen ekstraksi nikel dari bijih LS yang terbesar adalah 95% yang diperoleh pada konsentrasi asam sulfat 2M, suhu 80oC, rasio bijih/larutan asam sulfat 5%, dan waktu pelindian 4 jam. AbstractNickel extraction from nickel laterite ores particularly low-grade limonite ore is needed along with the increase of nickel consumption on the development of battery electric vehicle. Types and characteristics of nickel laterite ores affect greatly on the nickel extraction from these ores. This research conducted the extraction of nickel from limonite ore from different areas i.e. Halmahera Island (LH) and Sulawesi Island (LS) using atmosferic leaching. Sulfuric acid (1M) was used as leaching reagent. Leaching processes were carried out for investigating the effects of limonite ore characteristics (LH and LS), leaching temperatures (30oC, 50oC dan 80oC), concentration of sulfuric acid (0.5M; 1M; 2M), leaching time (15, 30, 60, 120, and 240 minutes), and ratio of ore amount to volume of leaching reagent on the nickel extraction from limonite ores. Experimental results showed that ore characteristic affected greatly on the leaching result and nickel leaching recovery. Nickel from LH ore could be extracted maximum (100%) using sulfuric acid 0.5M, temperature of 80oC, and leaching time 120 minutes (2 hours). Whereas, the highest nickel extraction percentage from LS ore is 95% using sulfuric acid 2M, temperature of 80oC, and leaching time 240 minutes (4 hours).
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Edeh, Joseph E., Adrian O. Eberemu, and Onah Agnes. "Lateritic Soil Stabilization of Reclaimed Asphalt Pavement as Flexible Highway Pavement Materials." Advanced Materials Research 367 (October 2011): 3–11. http://dx.doi.org/10.4028/www.scientific.net/amr.367.3.
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This paper presents the results of the laboratory evaluation of the characteristics of lateritic soil stabilized reclaimed asphalt pavements (RAP), using 0 – 2% cement, subjected to British Standard Light (BSL) compactive effort to determine their index, compaction and california bearing ratio (CBR) results. The result of the laboratory tests show that the properties of RAP improved when stabilized with lateritic soil, using up to 2% cement. The particle size distribution improved from poorly graded sandy GRAVELLY material for 100% lateritic soil and very sandy GRAVELLY material, to the gradation described as well graded very sandy GRAVELLY material for lateritic soil stabilized RAP, using up to 2% cement. The CBR results obtained from the study show that using the Nigerian General Specifications, 180% CBR value criterion, the maximum CBR of 55% (soaked) for the mix proportion; 40% Laterite + 58% RAP + 2% Cement for A-2-7(2) soil prescribed by the latter is not adequate for stabilization of base coarse. However, judging by the 24-hour strength gain from 17.9 (unsoaked) to 55% (soaked) CBR values, the material can be used as subgrade and subbase materials.
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Chang, Yong Feng, Chuan Lin Fan, Bin Chuan Li, Xiu Jing Zhai, and Ting An Zhang. "Selective Leaching Nickel from the Pre-Reduced Limonitic Laterite Ore at Atmospheric Pressure." Advanced Materials Research 560-561 (August 2012): 494–98. http://dx.doi.org/10.4028/www.scientific.net/amr.560-561.494.
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In this paper a novel method for selective leaching nickel from pre-reduced laterite ore at atmospheric pressure was reported. The reduced calcine was leached in thin acid liquor to liberate the nickel and iron together firstly. By properly controlling the leaching condition, the leached iron ion could hydrolyze as goethite precipitate and regenerate the acid consumed in the leaching procedure. Finally, the nickel is selectively extracted into the leaching solution. The main factors in the leaching process, such as reduction degree of the laterite ore, acidity of the leaching solution were investigated as influence on the nickel extraction. The test results showed that selectively leaching of nickel could be achieved with an extraction degree up to 90% by reducing most of the iron in the lateritic ore to wuestite and controlling the pH value of the leaching solution below 2.5.
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Razanajatovo, Harinivo Olsynthique, Serge Ravelomanantsoa, Elise Octavie Rasoazanany, Aristote Matondo, Colette Masengo Ashande, Muhammad Ridwan, Koto-te-Nyiwa Ngbolua, and Robijaona Rahelivololoniaina Baholy. "Effect of Cassava (Manihot esculenta Crantz: Euphorbiaceae) Starch on the Stabilization of Malagasy Lateritic Soil." Budapest International Research in Exact Sciences (BirEx) Journal 2, no. 4 (October 9, 2020): 467–81. http://dx.doi.org/10.33258/birex.v2i4.1261.
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Laterite is one of the most widespread raw materials, especially in Madagascar. Its valorization as a building material would help to solve many socio-economic problems in Madagascar as well as in Africa. The use of this type of material fits well within the framework of high environmental quality, since the process uses an abundant material that does not require too much energy for its manufacture because it is dried in the open air. The aim of this work was to stabilize the laterite with cassava starch. The valorization of the latter would contribute to the development of new building materials. The study focuses on the mechanical characterization of specimens made with Vontovorona laterite in different proportions, which goes hand in hand with the determination of the physico-chemical parameters of the starch. To make specimens, we used techniques such as extraction, sieving, heating, laterite-stabilizing dosage, mixing, rotting, moulding, clamping, demoulding, drying. The results obtained show that the best stabilizing material is obtained if 15% of starch is mix to lateritic soil. The compressive strength in the dry state of the test specimens (samples) gave a significantly interesting result with a value of 54.8 bars (85% laterite with 15% starch). Thus the use of starch as a stabilizer in construction gave satisfactory results. This eco-friendly process, simple in its steps and practice, should be popularized among artisanal brick makers. Thus, replacing proportions of the Portland cement in soil stabilization with Cassava starch will reduce the overall environmental impact of the stabilization process.
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Palenova, E. E., K. A. Novoselov, and E. V. Belogub. "Gold in weathering mantle of the Guiana shield (South America)." МИНЕРАЛОГИЯ (MINERALOGY) 5 (July 16, 2019): 83–100. http://dx.doi.org/10.35597/2313-545x-2019-5-2-83-100.
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The article describes mineral composition of laterite weathering mantle overlapping the Amamuri and Kontakt gold deposits in the greenstone rocks, located 20 km southeast of the Aurora deposit (reserves of 185 tons Au, Republic of Guyana). The major minerals of the weathering mantle include disordered kaolinite (35–90 wt. %), relict quartz and hydromica (up to 20 wt. % illite). The heavy concentrate is represented by limonite (up to 8 wt. % goethite), magnetite, hematite, ilmen-ite, anatase, ferrous rutile, psilomelane, pyrite, chalcopyrite, galena, sphalerite, covellite, zircon, tourmaline, epidote and amphibole. Native gold composes signifcant amount of heavy concentrates (up to 9 wt. %) and includes the following types: 1) lode gold in relict quartz veins and stockwork, 2) relict gold in laterite and 3) supergene gold. According to mineralogical studies, moderate late-ritization and monosialitization processes are probably due to erosion of ancient areal weathering mantle and the presence of immature laterites over the Amamuri and Kontakt deposits. Most amount of gold is relic. The processes of its redeposition and supergene alterations are weak. The dominant size of gold grains of <100 µm makes gravitational concentration of laterites more difcult, whereas weakly ordered kaolinite prevents agglomeration during cyanidation and heap leaching. Alluvial placers are probably more promising for exploration, since they provide natural fractionation of gold particles by size favorable for gravity extraction.
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Bhaskar, Dhaneesh, M. P. Prejith, K. P. Rajkumar, C. J. Alex, T. S. Prasad, and K. A. Sreejith. "Butterfly Diversity in Lateritic Biotope of Kavvayi River Basin, Kerala, India." Current World Environment 12, no. 1 (April 25, 2017): 132–41. http://dx.doi.org/10.12944/cwe.12.1.16.
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A study on butterfly diversity of lateritic biotopes of Kavvayi River Basin was conducted during February 2013 to January 2015. The study area represents diverse habitats that include sacred groves, laterite hills, riparian ecosystem, and kanams. A total of 140 species butterflies were recorded from the study area, among which the highest number of butterfly species were from the family Nymphalidae (48 species), followed by Hesperiidae (32 species), Lycaenidae (27 species), Papilionidae and Pieridae with 16 species each and 1 from the family Riodinidae. The present study revealed the faunal richness of the unique ecosystems and microhabitats in lateritic biotopes in terms of butterfly diversity. The study also highlights conservation significance of the area which is under severe human pressure including mining, habitat fragmentation and change in the land-use system.
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McDonald, Robbie G., and Jian Li. "The High Temperature Co-Processing of Nickel Sulfide and Nickel Laterite Sources." Minerals 10, no. 4 (April 14, 2020): 351. http://dx.doi.org/10.3390/min10040351.
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The pressure oxidation of low-grade nickel sulfide concentrate with high iron sulfides content generates significant amounts of sulfuric acid that must be neutralized. This acid can be utilized to leach metal values from ores such as nickel laterites. The present study demonstrates the use of a low-grade nickel concentrate generated from Poseidon Nickel Mt Windarra ore to enable additional nickel and cobalt extraction from a Bulong Nickel Operation nickel laterite blend. The co-processing of these materials at 250 °C, with oxygen overpressure, using total pulp densities of 30% or 40% w/w, and a range of nickel concentrate to nickel laterite mass ratios between 0.30–0.53, yielded base metal extractions of 95% or greater. The final free acid range was between 21.5–58.5 g/L, which indicates that enough in situ sulfuric acid was generated during co-processing. The acid was shown from mineralogical analysis to be efficiently utilized to dissolve the laterite ore, which indicates that the primary iron hydrolysis product was hematite, while the aluminum-rich sodium alunite/jarosite phase that formed hosts approximately 5% of the hydrolyzed iron.
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Wanta, Kevin Cleary, Felisha Hapsari Tanujaya, Ratna Frida Susanti, Himawan Tri Bayu Murti Petrus, Indra Perdana, and Widi Astuti. "Studi Kinetika Proses Atmospheric Pressure Acid Leaching Bijih Laterit Limonit Menggunakan Larutan Asam Nitrat Konsentrasi Rendah." Jurnal Rekayasa Proses 12, no. 2 (December 31, 2018): 19. http://dx.doi.org/10.22146/jrekpros.35644.
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A B S T R A C TKinetics study of atmospheric pressure acid leaching (APAL) process is indispensable for extractor design in an industrial scale. So far, the kinetic model used for this process is the shrinking core model. In this study, the shrinking core model was evaluated against experimental data for laterite leaching process using a solution of low concentration nitric acid (0.1 M). Variations in temperature and particle size were carried out at 303–358 K and <75–250 microns. Other operating conditions, such as pulp density, stirring speed, and time were kept at 20% w/v, 200 rpm, and 120 minutes, respectively. The model evaluation results showed that the shrinking core model was not suitable for this process because the process controlling stage is not just one stage only.Keywords: kinetics; laterite; leaching; shrinking core.A B S T R A KStudi terkait kinetika proses atmospheric pressure acid leaching (APAL) sangat diperlukan untuk proses perancangan ekstraktor dalam skala industri. Selama ini, model kinetika yang digunakan untuk proses tersebut adalah model shrinking core. Dalam studi ini, model shrinking core dievaluasi terhadap data percobaan proses leaching bijih laterit dengan menggunakan larutan asam nitrat konsentrasi rendah, 0,1 M. Variasi suhu dan ukuran partikel dilakukan pada 303–358 K dan <75–250 mikron. Kondisi operasi lainnya, seperti densitas pulp, kecepatan pengadukan, dan lama proses dijaga tetap pada 20%b/v, 200 rpm, dan 120 menit, secara berurutan. Hasil evaluasi model menunjukkan bahwa model shrinking core tidak cocok untuk proses ini karena tahapan pengendali proses tidak hanya satu tahapan saja.Kata kunci: kinetika; laterit; leaching; shrinking core
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Feng, Huimin, You Chen, Bo Li, and Yaoting Wu. "Molecular phylogeny of genus Musa determined by simple sequence repeat markers." Plant Genetic Resources 14, no. 3 (August 12, 2015): 192–99. http://dx.doi.org/10.1017/s1479262115000222.
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Musa L. was previously separated into five sections (Eumusa, Rhodochlamys, Callimusa, Australimusa and Ingentimusa) based on basic chromosome numbers and morphological characters. However, several molecular analyses currently support restructuring of Musa species into two sections, Musa and Callimusa. The application of simple sequence repeat molecular marker analysis to Musa phylogeny provided valuable, supplemental information about the classification of, and relationships between, Musa species and subspecies. Totally, 28 accessions of Musa acuminata Colla subspecies and varieties and 25 accessions of other Musa species were evaluated; 12 primers produced 91 polymorphic bands, polymorphic information content ranged from 0.4473 to 0.8394 (average = 0.7226), indicating that the primers showed a high level of polymorphism. Our results generally agreed with previous phylogenetic analyses based on molecular data. One clade comprised species of sections Australimusa and Callimusa (X= 10/9); most species of sections Eumusa and Rhodochlamys (X= 11) formed the other clade. The relationships between most species were as expected; however, some species did not conform to findings of previous studies. A wide range of variability was observed in the M. acuminata complex. M. acuminata var. chinensis and M. acuminata subsp. 522 showed the most distant relationships to other subspecies: Musa laterita, Musa ornata and Musa velutina clustered with M. acuminata var. chinensis, suggesting that they may constitute a secondary gene pool for the improvement of cultivated bananas. Molecular data indicated that Musa tongbiguanensis Chen You & Yao-Ting Wu, which was observed and described by our research group in Yunnan, China, was a distinct, new species.
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Abdou Lawane, Gana, Adamah Messan, Anne Pantet, Raffaele Vinai, and Jean Hugues Thomassin. "Local Materials for Building Houses: Laterite Valorization in Africa." Advanced Materials Research 875-877 (February 2014): 324–27. http://dx.doi.org/10.4028/www.scientific.net/amr.875-877.324.
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This paper presents the preliminary results of geological and geomechanical studies on the laterite stone exploited at Dano quarry in Burkina Faso. The field work described the geological structure of quarry sites and their environment to determine the rocks alteration and the links between the bedrock and lateritic material. Physic-mechanical properties have been studied for assessing the potentiality of this material for lightweight housing, to be completed with thermal and environmental considerations. Some social and economic evaluations are in progress in order to foster its utilization under local conditions
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Stanković, Srdjan, Srećko Stopić, Miroslav Sokić, Branislav Marković, and Bernd Friedrich. "Review of the past, present, and future of the hydrometallurgical production of nickel and cobalt from lateritic ores." Metallurgical and Materials Engineering 26, no. 2 (July 22, 2020): 199–208. http://dx.doi.org/10.30544/513.
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Laterite ores are becoming the most important global source of nickel and cobalt. Pyrometallurgical processing of the laterites is still a dominant technology, but the share of nickel and cobalt produced by the application of various hydrometallurgical technologies is increasing. Hydrometallurgy is a less energy-demanding process, resulting in lower operational costs and environmental impacts. This review covers past technologies for hydrometallurgical processing of nickel and cobalt (Caron), current technologies (high-pressure acid leaching, atmospheric leaching, heap leaching), developing technologies (Direct nickel, Neomet) as well as prospective biotechnologies (Ferredox process).
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Das, Anath Bandhu, Subrat Kumar Dehery, Kiran, Satya Narayan Jena, and Rabindra Kumar Sinha. "A New Seeded Diploid Accession of Musa laterita of Section Rhodochlamys From Gangtok, Sikkim, India with Morphology, Chromosome Number and Genome Size." CYTOLOGIA 85, no. 1 (March 25, 2020): 63–69. http://dx.doi.org/10.1508/cytologia.85.63.
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Baslayici, Serkan, Ozan Coban, Mehmet Bugdayci, and Mahmut Ercan Acma. "HYDROMETALLURGICAL NICKEL AND COBALT PRODUCTION FROM LATERITIC ORES: OPTIMIZATION AND COMPARISON OF ATMOSPHERIC PRESSURE LEACHING AND PUG-ROAST-LEACHING PROCESSES." Acta Metallurgica Slovaca 27, no. 1 (February 25, 2021): 17–22. http://dx.doi.org/10.36547/ams.27.1.740.
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Corresponding to the technological developments, production and consumption of nickel have increased greatly over time due to its unique mechanical and chemical properties. Therefore, the production of nickel will always keep its importance. The availability of laterite ores, which are oxide type ores, is 86% of the nickel reserves on the Earth, and the processes used in the production of nickel from sulfide type ores have negative environmental effects. Therefore, recovery of nickel from lateritic ores has become increasingly important in recent years. In this study, the aim was to determine the optimum parameters of nickel and cobalt production from limonite type lateritic nickel ores, which were taken from Manisa Caldag region of Turkey, using atmospheric pressure sulfuric acid leaching and pug-roast-leach process. When the results obtained in these processes were compared, it was found that the Ni leaching efficiency is nearly 8% higher and iron leaching efficiency (contamination) is nearly 4% lower in the pug-roast-leach process. Furthermore, the pug-roast-leach process was completed in 33% lower time compared to the atmospheric pressure sulfuric acid leaching process.
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Huang, Ying, Tong Zhen Bo, Zu Lian Zhang, and Ke Sheng Jin. "The Microstructure Characteristic of Compacted Laterite with Acid Pollution." Applied Mechanics and Materials 353-356 (August 2013): 1146–52. http://dx.doi.org/10.4028/www.scientific.net/amm.353-356.1146.
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s. The microstructure characteristic of compacted laterite with acid contamination was researched by means of electronic microscope scanning and microstructures image analysis in which the hydrochloric acid was used as pollutant and the acid concentration and curing history of samples were taken into account. It shows that acid pollution significantly influences the microstructure of laterite in which with more acid concentration and longer pollution times, the microstructure images behave lower compaction, blur particle edges, dissolution cement among particles, gluing coatings parceling particles, pores among particles and darker gray color. The corresponding parameters of the microstructure behave different properties in which with longer pollution times of samples, there is a maximum of porosity, girths of particles increase, number of particles decreases, the circularity of particles is not obvious, the directionality and the fractal dimension vary with magnification of the images and with more acid concentration, the girths and porosity increase, the circularity and fractal dimension decrease, the particle number and the directionality vary with the magnification of images. The result shows that the mechanism of the effect of acid contamination on laterites micro structures is that the acid erodes its particles and the cement among particles.
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AYODELE, Adekemi Loretta, Adefemi Daniel Adekoya, Abdulhalim Oshioke Mohammed, and Ayowande Oluwatosin. "Utilization of Phosphoric Acid and Lime for Stabilizing Laterite for Lateritic Bricks Production." Civil Engineering Dimension 23, no. 1 (April 20, 2021): 1–8. http://dx.doi.org/10.9744/ced.23.1.1-8.
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This study investigates the use of phosphoric acid (H3PO4) and lime in stabilizing lateritic soil for lateritic bricks production. Varying percentages (0, 2, 4 and 6%) of 1 M H3PO4, 5% lime and their combinations were mixed with lateritic soil for stabilization purpose. Hollow bricks were produced from the different mixes. The bricks were cured for 7, 14 and 28 days under ambient air condition. The compressive strength (fc), bulk density (pb), dry density (pd) and water absorption rate were determined at each of the curing days while the modulus of rupture (fr) and pH were determined after 28 days. The results show a maximum fc of 0.93 N/mm2 and 0.87 N/mm2 were obtained at 5% and 4% H3PO4 stabilization. The maximum pb and pd of 15.2 kN/m3 and 14.9 kN/m3 respectively were obtained at 4% H3PO4 stabilization. The maximum fr of 0.2 N/mm2 was obtained at combined 4% H3PO4 and 5% lime stabilization while none of the bricks passed the water absorption test.
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Bustamante Rúa, Moises Oswaldo, Sindy Dayanis Gonzalez Arias, and Pablo Bustamante Baena. "Nickel laterite concentration through a non-conventional method with surface sulfidization." DYNA 87, no. 215 (October 1, 2020): 18–27. http://dx.doi.org/10.15446/dyna.v87n215.85981.
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Nickel ores are found mainly as sulfides and laterites in oxidized ores, such as iron oxides, which are usually “Ni-bearing”. This investigation determined the physical-chemical conditions necessary to increase the tenor and recovery in lateritic deposits, with the implementation of a new technology that allows the increase of the tenor (a process called “up-grading”). The froth flotation is proposed as a concentrating process to increase the Nickel content in the lateritic deposits. By means of sulfidization and direct flotation, specific hydrophobicity of the mineral is achieved, substantially improving the nickel concentrations in the process, with recoveries close to 86%, which, compared with conventional direct and inverse floats without effecting this activation with Na2S, results in recoveries of 70% and 16%, respectively. The reverse flotation also increases the Nickel content with an approximate recovery of 70%; however, the froth flotation, with activation Na2S is still better.
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Qureshi, Kamil Ahmed, Muhammad Raza Shah, Ishaque Ali Meerani, Shah Fahad, Hamid Hussain, and Umer Habib. "Sedimentology and Economic Significance of Hangu Formation, Northwest Pakistan." International Journal of Economic and Environmental Geology 11, no. 1 (July 7, 2020): 48–55. http://dx.doi.org/10.46660/ijeeg.vol11.iss1.2020.411.
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The Hangu Formation (Paleocene) consists of sandstone, siltstone, carbonaceous shale, coal and laterite. It is well exposed in the Trans Indus Surghar range and the southern Hazara basin. The sandstone is yellowish brown, fine to coarse grained and medium to thick bedded. The sandstone of the Hangu Formation is classified as quartz arenite on the Q-F-L diagram. It is mostly grain supported and are cemented by silica cement. The study of different stratigraphic sections reveal that Hangu Formation can be sub-divided into a number of lithofacies on the basis of sedimentary structures and lithological variations. These include lateritic lithofacies, coal and carbonaceous shale, cross-bedded sandstone, bioclastic limestone and bioturbated sandstone. All these lithofacies are well-developed in the Baroch Nala section of the Surghar range except the lateritic lithofacies which contains a thin bed of ferruginous clay. In the studied sections of the Hazara basin, the lateritic lithofacies is the only well-developed lithofacies present in the area. The coal occurs at two stratigraphic levels in the Baroch Nala section. The lower coal seam is thick and its chemical study indicates higher calorific value and carbon content than the upper coal seam and with low moisture/ash content. On the basis of the calorific value, the coal of the Hangu Formation is characterized as high volatile bituminous. The degree of laterization is strong in the Langrial and Khanpur sections and moderate in Baroch Nala section.
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Qureshi, Kamil Ahmed, Muhammad Raza Shah, Ishaque Ali Meerani, Shah Fahad, Hamid Hussain, and Umer Habib. "Sedimentology and Economic Significance of Hangu Formation, Northwest Pakistan." International Journal of Economic and Environmental Geology 11, no. 1 (July 7, 2020): 48–55. http://dx.doi.org/10.46660/ojs.v11i1.411.
Full textAbstract:
The Hangu Formation (Paleocene) consists of sandstone, siltstone, carbonaceous shale, coal and laterite. It is well exposed in the Trans Indus Surghar range and the southern Hazara basin. The sandstone is yellowish brown, fine to coarse grained and medium to thick bedded. The sandstone of the Hangu Formation is classified as quartz arenite on the Q-F-L diagram. It is mostly grain supported and are cemented by silica cement. The study of different stratigraphic sections reveal that Hangu Formation can be sub-divided into a number of lithofacies on the basis of sedimentary structures and lithological variations. These include lateritic lithofacies, coal and carbonaceous shale, cross-bedded sandstone, bioclastic limestone and bioturbated sandstone. All these lithofacies are well-developed in the Baroch Nala section of the Surghar range except the lateritic lithofacies which contains a thin bed of ferruginous clay. In the studied sections of the Hazara basin, the lateritic lithofacies is the only well-developed lithofacies present in the area. The coal occurs at two stratigraphic levels in the Baroch Nala section. The lower coal seam is thick and its chemical study indicates higher calorific value and carbon content than the upper coal seam and with low moisture/ash content. On the basis of the calorific value, the coal of the Hangu Formation is characterized as high volatile bituminous. The degree of laterization is strong in the Langrial and Khanpur sections and moderate in Baroch Nala section.
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Subagja, Rudi. "KINETIKA REAKSI PELARUTAN NIKEL DARI KALSIN NIKEL LATERIT [Kinetics of Nickel Dissolution from Nickel Laterite Calcine]." Metalurgi 30, no. 2 (December 3, 2015): 71. http://dx.doi.org/10.14203/metalurgi.v30i2.38.
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Hyoumbi, William Tchungouelieu, Patrick Pizette, Armand Sylvain Ludovic Wouatong, and Nor-Edine Abriak. "Mineralogical, Chemical, Geotechnical and Mechanical Investigations of Bafang Lateritic Fine Soils Formed on Basalts (West-Cameroon) for Road Embankment Purpose." Earth Science Research 7, no. 2 (May 4, 2018): 42. http://dx.doi.org/10.5539/esr.v7n2p42.
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The present paper treats the relationship between geotechnical parameters and the mineralogical compositions, in order to understand the behavior of the Bafang lateritic fine soils and their efficient use as road embankment materials on the other hand. Thus, the field campaigns have permitted to distinguish two facies of Bafang lateritic fine soils: reddish and yellowish facies. The X-ray diffraction (XRD), the thermo-gravimetry analysis (TGA) and the X-ray fluorescence (XRF) have revealed that the reddish facies contents: kaolinite (53.34% -48.29%); hematite (16.62% - 17.40 %); gibbsite (8.26 % - 16.54%), ilmenite (7.6 % -7.98%), quartz (1.92 % - 4.65 %), illite (2.65% - 1.99 %) and accessories minerals as florencite (1.45%); montmorillonite (0.90 %) and plagioclase (0.69 %); while the yellowish facies is composed of : 65.1 % kaolinite, 11.2 % gibbsite, 9.64 % goethite, 7.02 % quartz, 3.23 % ilmenite and 2.08 % of illite. Their Silica/sexquioxide ratios correspond to those of moderate laterite. The geotechnical and mechanical characteristics have shown that the reddish and yellowish facies are respectively silty clay and sandy silt. They are plastic to very high plastic and moderately clayey to clayey materials. Moreover, they are medium swelling to high swelling. The IBR values more than 40% and the soaked CBR values prove that these materials belong to the S4 bearing capacity class. The minimum values of UCS and Rt are respectively 1.7 MPa and 0.17 MPa. Then, the results of geotechnical and mechanical properties combining to those of XRD, TGA and XRF have demonstrated that the fine lateritic soils with low silica/sexquioxide ratios values (less than 1.6) are suitable for road embankment.
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Hermann, KEYANGUE TCHOUATA Jules, Luc Leroy MAMBOU, Casimir GOUAFO, and FOADIENG Emmanuel. "Model of the Evolution of the Modulus of Elasticity E, As A Function of the Bearing Capacity Index ICBR of Gravelly Laterites. Case of the Banka Locality (Westcameroon)." International Journal of Emerging Technology and Advanced Engineering 10, no. 11 (November 30, 2020): 96–103. http://dx.doi.org/10.46338/ijetae1120_11.
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The objective of this study is to model the evolution of the values of the modulus of elasticity E as a function of the bearing capacity index ICBR of Banka lateritic gravel, with the aim of reducing the cost and time of laboratory tests for the determination of the modulus of elasticity and the CBR index. Geotechnical identification tests were carried out on 18 laterite samples taken from the Banfeko, Bakoye and Ketcho sites in the Banka locality. ICBR values ranged from 31 to 51.92 and E-modulus values ranged from 80 MPa to 165 MPa. The resulting model is polynomial for all sites of the form: E = a* ICBR 5 + b* ICBR 4 + c* ICBR 3 + d* ICBR 2 + e* ICBR +f This model has the highest degree of interdependence of value 1.