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By Yoshinori Kurumada, Masaya Watanabe, Kenji Sasa

"The Port of Yokohama is strengthening its international competitiveness as a strategic container port in order to respond appropriately to global exchange and shipping demands. Thus, the Minami Honmoku main Pier is currently being developed. The high-standard container terminals MC-1 and MC-2 have already started their service, and the development of the container terminals MC-3 and MC-4 is currently in progress.Because the South Honmoku Pier plays an important role in waste disposal management of Yokohama, a final waste disposal site (controlled final landfill site) is being developed in Block 5 to provide long-term and stable reception of waste that will be generated in the city. For this project, a revetment with water-blocking properties and an extension approximately 1.7 km in length is being built in order to prevent water from leaking from the disposal site. The base part of the revetment will be subjected to foundation improvement using the Cement Deep Mixing (CDM) method in order to secure water shielding of the soft sediment underneath the water, prevent slipping of the seawall, reduce the amount of subsidence, and increase the foundation support force.This report presents a preliminary study on using CDM on reclaimed soil and the construction process of the development project of the disposal site in Block 5 of the Minami Honmoku Pier, which has been underway since 2007.ABOUT MINAMI HONMOKU PIERThe development of the Minami Honmoku Pier started in 1990. It was designed to develop high-standard berths with greater water depths in order to handle the increasing volume of foreign container cargo and growing size of vessels. Figure 1 shows the layout of Minami Honmoku Pier. In April 2001, the Phase 1 (MC-1 and MC-2) began services. This is the newest pier in Port of Yokohama.This pier has one of Japan’s largest terminal areas (40 ha) and is equipped with 22 row-type mega gantry cranes capable of handling the newest ultralarge container ships. The pier has a quay with a water depth of 16 m, which is the first in Japan. The pier is equipped with advanced facilities and equipment to let Port of Yokohama be internationally competitive and function as an international commercial hub. An innovative system for high-efficiency transport is currently being introduced; it includes the installation of waiting vehicle lanes and a reservation-based loading and unloading system.Since the fiscal year 2007, a new container terminal (MC-3) with a -20m deep quay capable of handling the increased size of container ships and the diversification of port logistics has been under construction and is nearly completed."

Jan 1, 2015

By Paul Bedard, Réal Daigneault, Guy Perrault

"La mine Lamaque est située a Val d'Or, Québec; les roches hônes appartiennent au groupe de Malartic, partie supérieure, et sont des andésites et des pyroclastites. On y retrouve deux formes d'intrusifs; des petites cheminées (ca. 150 m D) et des dykes (ca. 10 m d'epaisseur). Les petit es cheminées contiennent:1 - des diorites et des tonalites (cheminées principale, est et ouest) d'affinité calco-alcaline: Zr 140 ppm, Sr 761 ppm, P2O5 0.31% et (La/Sm)n 3.0;2 - des diorites (cheminée 4) d'affinités tholéiitique: Zr 32 ppm, Sr 181 ppm, P2O5 0.27% et (La/SM)n 1.5.La diorite de la cheminée no 5 contient deux fractions, une de chacune de ces deux affinités. Les dykes tant de porphyre feldspathique quartzifére que ceux de prophyre feldspathique sont d'affinité calco-alcaline: Zr 83 ppm, Sr 500 ppm et P2O5j 0.10%.Le gisement de 10 mine 2 est filonien: veines subhorizontales (""flats "") surtout et veines sub-verticales dans des zones de cisaillement. Le dernier réajustement structural de direction de compression nord-sud a broyé le quartz des veines existant es et rendu possible leur minéralisation. Les veines minéralisées contiennent du quartz, de la tourmaline, de la calcite avec des traces de scheelite, de pyrite et d'or; elles sont bordées par de minces (2 à 20 cm) bordures d'altération où l'on retrouve un enrichissement en carbonate, paragonite, apatite, rutile, saphène et zircon et où les phases ferromagnésiennes sont disparues. On a documenté le migrations géochimiques suivantes:I - de la bordure d'altération vers l'éponte, K2O, Rb et MgO;2 - de l'éponte vers la bordure d'altération, Na2O;3 - de l'éponte vers la veine, SiO2.P2O5, TiO2, Zr, Y, Nb et CaO sont enrichis dans la bordure d'altération."

Jan 1, 1983

By Hugo de León Carvalho Cedro

O presente trabalho tem como objetivo avaliar os efeitos da degradação da superfície de lentes de contato via métodos ópticos. Sendo biomateriais, as lentes estão em contato direto com estruturas sensíveis do corpo humano e seu uso surge da necessidade de reduzir enfermidades, propiciando melhora da acuidade visual e proteção ocular. Outro aspecto relevante é que as lentes se tornam uma nova estrutura refrativa de entrada da luz no globo ocular, e desse modo devem manter características de transmitância compatíveis com a córnea. Com o uso das lentes, é esperado uma degradação natural das propriedades ópticas e superficiais da mesma. Para avaliarmos essa degradação, foi planejado um experimento com um ensaio de degradação. O ensaio de degradação visa comparar o efeito de diferentes soluções simuladoras sobre a superfície das lentes tóricas: solução extrema de acetato de potássio 5% pH5, solução fisiológica usada pelo fabricante do tipo Boston Simplus multiação e solução de água ultrapura obtida de um dispositivo milli-Q (controle). O efeito da degradação foi analisado através do estudo das variações da topografia e da transmitância da lente.

Oct 30, 2017

By J. C. Kerkering, P. M. Daling

This paper discusses a study performed to evaluate the feasibility of transferring formal system safety assessment technology to the mining industry. A representative listing of formal techniques was evaluated to select the most useful methods for the mining industry to implement. Criteria for selecting methods included the interests, needs, and requirements of mine safety officials. This paper describes one of the selected methods, preliminary hazards analysis (PHA), and illustrates the analysis procedure for a mining example. This study also includes an assessment of the adaptability of selected methods to a user-interactive computer system for use by mine safety personnel. This paper includes a description of a conceptual computerized PHA-type safety program that facilitates performance of the safety analysis and can accommodate updates and revisions as necessary.

Jan 1, 1983

By R. B. Elver

The level of steel consumption per capita is one of the principal indicators of a country's standard of living. It is no coincidence that the materially advanced nations possess viable iron and steel industries to provide a reliable and economic source of steal for the manufacturing industries. No other metal is as dominantly important in manufacturing as steel. The blast furnace - steel furnace complex based on coking coal, ferrous scrap and iron ore - continues to be the principal steel-producing method. Less important is the electric furnace method based on scrap, In recent years, there has been considerable interest in the many direct reduction processes that are not dependent on coking coal but usually produce a product for further refining in steel furnaces. No matter which series of processes are used, iron ore is essentially the only source of virgin iron units. Thus, to such a vital and capital-intense industry as steel, access to a relatively inexpensive, long- term supply of iron ore is essential.

Jan 1, 1964

By Deyve Drengson Carneiro Vieira

O objetivo desse trabalho é identificar a eficiência térmica do glendon de uma empresa do setor siderúrgico mineiro. Tendo em vista que quanto mais eficiente for o equipamento, maior é o aproveitamento da energia fornecida e também menor é o consumo de carvão vegetal no alto-forno, reduzindo o OPEX. Este trabalho foi um estudo de caso baseado na análise de diferentes referências bibliográficas e através de estudos prévios e dados reais. O glendon em estudo apresentou eficiência térmica de 53,1%. Estudos mais recentes apresentaram eficiência de 67,4% utilizando chicanas no interior do glendon alterando o fluxo gasoso. O combustível do glendon é o gás do topo do alto-forno recuperado. A energia proveniente da combustão representa 89% da entrada de energia no regenerador, o que mostra quão importante é uma queima estável do GAF no glendon. Observou-se um desperdício de 45,5% da energia de combustão que saem pelos gases na chaminé, sendo uma oportunidade futura de estudo para reaproveitamento dessa energia

Aug 17, 2017

By Euler De Souza, J. Daniel Stinnette, Julian Varaschin

"This paper outlines some of the factors that affect the airflow required for the ventilation of modern diesel-powered equipment and of electric equipment and examines how they can be applied in determining reasonable ventilation rates for Tier IV compliant diesel equipment and for electric equipment operating in mining environments. Airflow calculations for modern diesel-powered equipment and for electric equipment are more complex and must be based on a combination of factors that are unique to each mine. Methodologies for ventilation rate determinations for each case are proposed in this paper.INTRODUCTIONTraditionally, airflow requirements for production and support equipment operating in underground mines have been determined by multiplying the vehicle power by a ventilation rate that was either mandated by regulations or determined empirically from known quantities. However, in light of the drastic reductions to diesel equipment emissions mandated by the US EPA Tier IV and EURO Stage 4 regulations, there is still a great deal of uncertainty in the underground mining industry among those responsible for the ventilation of planned new mines or the expansion of current mines. The question remains, what ventilation rates should the ventilation system designer apply for modern diesel equipment?Also, given the ongoing development of grid/battery-electric equipment and active construction of fully electric mines, it has become critical to determine adequate airflow rates per brake kilowatt of electric engine power. One of the most important criteria for determining ventilation rates for electric equipment is the amount of heat they generate, as this is the most significant emission produced by electric equipment (which do not produce exhaust gases or particulates). Therefore, ventilation rates required to dissipate heat from electric equipment must be suitably determined for all electric vehicle fleets operating in underground mines."

Jan 1, 2019

By M. J. Ankeny, J. J. Forbes

The United States Bureau of Mines often receives inquiries from the mineral , petroleum , and allied industries concerning the essential steps to be taken in the formation of Holmes Safety chapters and councils . The purpose of this circular is to answer in a general way such inquiries and to relate briefly the history and work of the Holmes Safety Association to the present date .

Jul 1, 1931

By T. McWaters

Miami Copper Company began a block-caving operation in 1911 using a gravity mill to separate copper minerals from the Pinal Schist host rock. The tailing was deposited by the upstream method using perimeter launders and spigot valves in six canyons adjacent to the mill until 1932. In 1928 the larger and more distant Solitude tailing pile was developed which by 1932 was receiving all tailing except for upsets. In 1925 Miami Copper converted its gravity mill to flotation which began to produce higher sulfide copper recoveries.

Jan 1, 1990

By B J. Monaghan, R J. Longbottom, S Prabowo, D Del Puerto, B Maisuria, C W. Bumby

The use of hydrogen as a reducing agent can substantially reduce carbon dioxide (CO2) emissions from the ironmaking process. Iron ore fines can be reduced in a fluidised bed (FB) using hydrogen (H2) at high temperatures (>800°C), although several studies have reported the sticking of particles which causes the bed to defluidise, effectively shutting down the process. Here, we report results from the reduction of New Zealand (NZ) titanomagnetite (TTM) ironsands in a small-scale laboratory FB (100 g) at temperatures between 800–1000°C using H2 flow rates up to 5 standard L/min. No sticking phenomena are observed under any of these conditions, which is attributed to the formation of a stable titanium-bearing oxide layer on each particle’s exterior, preventing iron-iron contact at the particle surfaces. Pre-oxidised NZ TTM ironsands have also been studied and shown not to stick. Interestingly, at lower reaction temperatures the reduction kinetics for pre-oxidised ironsands is faster than for as-received ironsands. This increased kinetic rate can be attributed to the preoxidation stage inducing micro-fractures that create a void for the hydrogen to diffuse into the inner regions of the particle. In addition, oxidation of TTM appears to segregate the particle into two distinct phases, a high Aluminium-Magnesium (Al-Mg) phase and a high Titanium (Ti) phase. The findings are important as increasing the operating temperature of the FB reactor results in a faster reaction rate and higher gas utilisation, making the process more economically attractive. Furthermore, oxidation of NZ TTM ironsands results in a faster reduction rate at lower temperatures (800°C– 900°C) opening the opportunity to reduce the reaction temperature which might be beneficial in a final commercial-scale process.

Sep 18, 2023

By Laís Couto dos Santos

A corrosão é definida como sendo um conjunto de fenômenos de deterioração dos materiais em consequência de reações entre o material e o meio. Em instalações metálicas, tais processos são monitorados através de cupons de perda de massa. Quando o ataque se evidencia pela formação de cavidades com pouca perda uniforme, ele é denominado corrosão por pites. As empresas de monitoramento de corrosão adquirem cupons de diferentes fornecedores, e pouco se observa quanto ao tipo de processamento durante a fabricação, a composição química, a microestrutura, entre outros parâmetros e o quanto, podem alterar a confiabilidade dos resultados. O presente trabalho tem como objetivo avaliar o desempenho de cupons aço carbono, relacionando a composição química, densidade de inclusões e pites de corrosão presente em cupons. Na caracterização foram envolvidas as análises química e microscópica. Os cupons foram ensaiados em loop de corrosão tendo como fluido a água potável. Para determinar a densidade, área e profundidade dos pites de corrosão foram adotados as normas NACERP0775 e ASTM G46-94. Foi observada uma relação direta entre o teor de enxofre e a densidade de inclusões e, consequentemente, entre a densidade de pites presente nos cupons, após ensaio em loop de corrosão.

Aug 17, 2017

By CIM Mineral Resource, Mineral Reserve Committee

The CIM Mineral Exploration Best Practice Guidelines (the Exploration Guidelines) have been prepared to assist professional geoscientists and engineers to conduct consistently high-quality work in order to maintain public confidence. The Exploration Guidelines are meant to assist professional geoscientists and exploration practitioners in planning, supervising, and executing exploration programs. In Canada, there are generally two types of public resource reporting: “Disclosure”, as defined by NI 43-101, is the reporting of technical information to the public and market participants for securities legislation purposes where a Qualified Person (QP) must be involved, and reporting of exploration information for governmental agencies to support obligations under laws including the Mining Acts of each of the Provinces and Territories. The Exploration Guidelines are also relevant where the results will not be publicly reported but are intended for internal company use. While this document is intended as guidance for work conducted or supervised by geoscientists in Canada, many of the practices described herein can be adapted to mineral exploration activities in other countries. The Exploration Guidelines are not intended to inhibit original thinking, or to prevent the application of new approaches that may develop into fundamental components of successful mineral exploration programs. Rather than provide prescriptive solutions to specific issues, they include general guidelines for current professional practice and to demonstrate and defend the merits of new methods. These guidelines do not preclude individuals and companies from developing more detailed guidelines specific to their own requirements. The initial version of the Exploration Guidelines was prepared by the Canadian Institute of Mining and Metallurgy and Petroleum (CIM) Exploration Best Practices Committee and adopted by CIM Council on August 20, 2000. On January 9, 2018, CIM Council formed a new committee, the Mineral Resources and Reserves Committee (CIM MRMR Committee) with a mandate to, among other things, update the Exploration Best Practice Guidelines. The mandate for the committee was accepted by CIM Council on March 2, 2018. The new document was adopted by the CIM Council on November 23, 2018.

Nov 23, 2018

By Paula Rodrigues Caumo

A aterosclerose é um termo geral relativo a diversas doenças relacionadas ao espessamento e perda de elasticidade da parede arterial. Atualmente os maus hábitos alimentares, combinados ao sedentarismo, podem levar a ocorrência de elevados níveis de colesterol na corrente sanguínea. Este fato aumenta o risco de obstrução dos vasos sanguíneos, limitando o fluxo do sangue para o coração. Desta maneira, para desobstruir o vaso sanguíneo e manter o lúmen arterial aberto é colocado um stent. Os stents são redes, normalmente de ligas metálicas, que servem para desobstruir os vasos sanguíneos. O tratamento de doenças das artérias coronárias e periféricas usando stents metálicos tem sido adotado nas intervenções médicas nos dias de hoje. No entanto, surgiram argumentos que indicavam os benefícios de remover o stent após este ter feito a desobstrução, originando desenvolvimento de stents biodegradáveis. Estes exigem propriedades mecânicas adequadas, biocompatibilidade adequada, garantindo uma baixa toxicidade dos produtos de degradação. Com isso, o objetivo deste trabalho é o estudo preliminar sobre stents metálicos biodegradáveis, como ferro puro, magnésio. Além disso, avaliar se os mesmos são adequados para aplicação à stents biodegradáveis, avaliando as propriedades mecânicas dos metais, biocompatibilidade e toxicidade dos compostos degradados ao longo do tempo de implantação.

Aug 17, 2017

By Tony Dunn

FMC Corp. achieved a significant cost reduction at its Green River, WY soda ash operations using a new proprietary solution-mining and processing technology. In phase one of the program, trona ore is dissolved, recovered and processed with the new technology. It is then fed into an existing refining plant, replacing dry mined and calcined trona ore. Phase two produces a final high-purity product. It also increases capacity by 635 kt/a (700,000 stpy). Both phases were completed under budget and ahead of schedule. This $120-million expansion project uses a new process and a new team to derive soda ash in a more cost-effective and environmentally friendly manner. The team successfully introduced solution-mining technology - with a liquid solution injected into previously mined sections of the mine. This shift in techniques signified a new era for soda ash production. The project is an example of teamwork at its best. For it to be successful, FMC had to work within several different areas inside and outside of the company. Engineers, contractors, mechanical operators and technical people were needed who could blend in with FMC's existing in-house team.

Jan 1, 1999

By Bruno Rodrigues Henriques

O entendimento, controle e otimização do rendimento de aço líquido, em uma aciaria LD, é uma tarefa complexa e desafiadora. Qualquer projeto que se disponha a otimizar o rendimento de aço líquido irá se deparar com enormes dificuldades técnicas e operacionais. A despeito de todas as dificuldades e em função da importância do rendimento de aço líquido, uma vez que o mesmo tem forte impacto no custo de produção, toda aciaria procura manter essa variável de processo sob estrito controle. Esse trabalho se propõe a mostrar todas as etapas da condução de um projeto, desenvolvido e implantado em 2014, que tinha como foco entender, controlar e otimizar o rendimento de aço liquido. Durante o desenvolvimento do projeto, foi encontrado um total de 19 desvios e foram implementadas 23 ações corretivas. O valor do rendimento, que antes do projeto estava em torno de 91,6%, evoluiu para uma média de 93,5% em 2015 e 2016. Esse aumento de 1,9%, em média, no valor do rendimento de aço líquido, proporcionou uma expressiva redução no custo de produção na aciaria.

Aug 17, 2017

By M. B. Ramachandra Roa

This paper records the results of the earth resistivity surveys made in the Godavari River in connection with the Ramapadasagar project. After describing the topographical and geological features of the area, the results of the investigation at the several sites have been mentioned. Further, a detailed account has been given of the resistivity methods adopted, the apparatus used and the interpretation of the curves. The resistivity measurements carried out over the water course have been specially outlined, and a review of the verification of the electrical indications by drilling in a number of cases, has also been presented. Introduction The Government of Madras has under consideration the Ramapadasagar project which is estimated to cost some Rs.660,-000,000 (about two hundred million dollars). The most essential feature of this project is the construction of a high dam across the Godavari near Polavaram for impounding the waters of this great river of South India, whose maximum discharge is 2 million cu secs in flood time. It is estimated that when the proposed reservoir is constructed, about one million tons of rice could be produced annually under irrigation. To those who have had any acquaintance at all with the recent distressing famine conditions which India has passed through and is still undergoing, the Lounteous effects which this project will bring about to the country in the future, are obvious. In the region of the proposed reservoir, the river flows for several miles through a hilly tract, hemmed in between flanks of hard, solid rock; but the river bed is mostly sandy. A few bore holes put down in this sandy bed touched rock at a depth of 180 to 200 ft. The river bed is about jo ft above the mean sea level (m.s.l.) and the bedrock was found at —125 to —160 ft m.s.l. The crest of the dam is proposed at +162 ft m.s.l. The proposed dam mould therefore be about 120 to 130 ft above the river bed, and the foundations would have to reach down nearly zoo ft below the bed at the deepest part. A number of alternative sites were proposed for investigation, and it became necessary to quickly ascertain the bedrock topography at these sites. Dr. M. S. Krishnan,* who was consulted in the matter, furnished a detailed account of the geological features of the region and suggested a geophysical investigation which the writer carried out from February to April 1944, employing solely the electrical resistivity methods. The total length of the survey lines for the electrical measurements amounted to 62,600 ft and the number of resistivity determinations was about 2500. Altogether nine alignments for the dam were inten-

Jan 1, 1949

By Rosiane Mary Rezende Faleiro

O carvão vegetal, CV, é o componente individual com maior impacto no custo final de uma usina integrada. Diante desta realidade, foi desenvolvido um processo de carbonização contínua, uma tecnologia moderna que a diferencia das carbonizações tradicionais, permitindo que o CV produzido tenha melhores características físicoquímicas. Sendo assim, o desafio agora é encontrar condições operacionais adequadas para produzir em larga escala a um custo competitivo. Com base nisso, desenvolveu-se este trabalho com o objetivo de avaliar o desempenho de um altoforno, em condições reais de operação e em escala industrial, utilizando dois tipos de carvões (CVs): CV Referência e CV produzido por carbonização contínua (Carboval). Os principais parâmetros operacionais foram monitorados. O CV Carboval apresentou melhores resultados para as análises químicas e granulométrica, melhor permeabilidade no alto-forno e menor consumo bruto, demonstrando sua viabilidade técnica.

Aug 17, 2017

By Pilkington T, Noy A

The Yallourn North Extension (YNX) open cut mine ceased mining operations in early 1989. YNX may be used again for coal supply at the discretion of the Coal Corporation Of Victoria (CCV); this has resulted in the need for interim rehabilitation of the site which may last many years, or indeed, permanently.The site has suffered substantial surface erosion over the years with large areas of bare clay and coal batters remaining exposed. The first priority is to reduce the quantity and improve the quality of stormwater runoff from the site. This is best achieved by appropriate revegetation and the use of existing landform depressions as silt trap/wetland areas. Proposed rehabilitation needed to take into account the sensitive fire safety of the open cut and the option to re-open the mine if CCV deems appropriate.The authors detail the factors involved in the rehabilitation proposal and the multi-disciplinary approach to planning including engineers, scientists, a forester, landscape architects and community input. The rehabilitation design included early consideration of land use and ongoing maintenance issues linked to water quality improvement factors including vegetation. Engineering input was required for reshaping and clay covering exposed coal batters and the design of silt traps which will revert to wetlands in future. The integration of each discipline has produced a rehabilitation design pleasing to both the SECV and community alike.

Jan 1, 1992

By N. S. Dalal, X. Shi

"Electron spin resonance (ESR) measurements provide evidence for the formation of Cr(V) intermediates in the enzymatic reduction of Cr(VI) by glutathione reductase (GSSG-R) in the presence of NADPH, indicating an initial single-electron transfer step in the reduction mechanism. Depending on the pH, at least two different Cr(V) species are generated which are relatively long-lived. In addition, we have detected the hydroxyl (·OH) radical formation during the GSSG-R catalyzed reduction of Cr(VI) by spin trapping, employing 5,5-dimethyl-1-pyrroline-N-oxide (DMPO) and a-(4-pyridyl-1-oxide)-N-tert-butylnitrone (4-POBN) as spin traps. Superoxide dismutase (SOD) causes only a minor effect on the ·OH radical and Cr(V) formation, indicating that the ~ - is not significantly involved in the reaction mechanism. Catalase enhances the Cr(V) formation and substantially inhibits the ·OH radical formation, indicating the involvement of hydrogen peroxide (H20 2) in the reaction mechanism. Addition of H20i suppresses Cr(V) and enhances the ·OH radical fonnation. Measurements involving N-ethylmaleimide show that the Cr(V) species, produced enzymatically by the reduction of Cr(VI) by GSSG-R, react with H2O2 to generate ·OH radicals, which might participate in the initiation of Cr(VI) carcinogenicity.INTRODUCTIONC(VI) compounds have been found to exert serious toxic and carcinogenic effects on humans and animals [1-4) and to cause mutations in bacteria and transformation of mammalian cells [5-8). In contrast, most Cr(lll) compounds are relatively nontoxic, noncarcinogenic, and nonmutagenic [9, 10]. Cr(VI) and Cr(lll) oxidation states are different in their metabolic pathways: Cr(VI) ions are rapidly transported across cellular membranes [2, 11-13), while Cr(lll) moieties do not easily penetrate cells and are not oxidized by cellular constituents [3]. Since it is known that the reduction of Cr(Vl) is required for its reaction with DNA [2], the molecular mechanisms for the intracellular Cr(VI) reduction have been the focus of studies during the past decade but the details are still not understood."

Jan 1, 1990

The Mammoth Mine is located some five kilometres from the town of Gunpowder which is approximately 120 km north-west of Mount Isa in Queensland.

Jan 1, 1993