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By Y. Kurokawa, R. Kurosawa, I. Iwata, I. Fukuoka, N. Sugita

INTRODUCTION The Ningyo-toge Mine is located in the western part of Honshu, about 800 km from Tokyo. Since the discovery of uranium ore deposit at Ningyo-toge in 1955, different kinds of mining and milling tests have been carried out. A new pilot plant of milling and UF6 conversion is also being under construction. Operations are scheduled to start by the end of this year. In 1979, the uranium enrichment pilot plant was constructed at Ningyo-toge and test operations have started. Thus, the Ningyo-toge area is assigned to undertake the Research and Development of the upstream of the nuclear fuel cycle in Japan. PNC has been strengthening its security measures more than ever. This paper will focus on the disposal of wasted material, especially on the disposal of heap leaching residue, in Japan. URANIUM ORE DEPOSITS The uranium of the Ningyo-toge Mine is characterized genetically by epigenetic sedimentary type deposits. They occur in the host rock of Neogene tertiary fluviatile conglomerates and sandstones which unconformably overlies the Mesozoic-Palaeogene granitic basement covered with lucustrine deposits and volcanic ejecta. More than 12 deposits have been found over the area of approximately 160 km2, and distribution of the deposits are strongly controlled by the so-called channel structure, probably remnants of paleo-streams on the denudation surface of the underlying grantic basement. Each ore body has different shape and dimension respectively, but about 2-3 meters thickness with the average grade of 0.05-0.2% U308 is common feature of the ore bodies. The ore is soft and loose, and it is composed of common rock forming minerals of allogenic origin and their altered products. The chemical composition of the ore depends on the constituents of the country rocks or the pebbles. A primary mineral, ningyoite and secondary mineral, autunite are major ore minerals, although three primary tetravalent minerals and thirteen secondary hexavalent minerals have also been detected. MINING EXPERIMENT Since 1959, various types of underground mining tests have been carried out at Ningyo-toge Mine. The room and pillar method was safe and simple, although the uranium ore recovery was below 70%. After experiment of the retreating long-wall method and slicing mining method, it was found that the modified long wall method was the most appropriate for the underground mining of the Ningyo-toge uranium deposits. This method was completed successfully to increase efficiency up to 2 or 3 times, as compared to conventional methods. MILLING EXPERIMENT In 1964, a small test mill was constructed at Ningyo-toge, and a milling experiment using the Ningyo-toge uranium ore was started. Re-modelling of equipments and improvement of the process lead to the establishment of the technique of the so-called wet process, and produce UF4 directly from the ore. The flow diagram is shown in Fig. 1.

Jan 1, 1981

By Douglas Henrique Milanez

A nanocelulose possui grande potencial de inovação e apelo sustentável, podendo ser obtida a partir de três vias principais: processo mecânico, hidrólise ácida e biossíntese bacteriana. Poucos estudos verificaram os avanços tecnológicos, bem como as principais organizações que dominam tecnologias envolvidas nas três vias principais de obtenção. Este estudo objetivou mapear as principais organizações e caracterizá-las conforme o processo de obtenção, mediante indicadores elaborados a partir de registros bibliográficos de documentos de patente indexados na base de dados mundial Derwent Innovations Index. Foi efetuada a mineração de dados para analisar a evolução do patenteamento, os principais titulares e os subdomínios tecnológicos no período de 2002 a 2011. Também foi realizada a mineração do texto contido nos títulos e resumos dos registros bibliográficos para mapear os processos de obtenção de nanocelulose e suas relações com os titulares. Os resultados indicaram o envolvimento de diversas instituições, sobretudo da China, dos EUA, do Japão e da Finlândia, além da característica emergente dos desenvolvimentos tecnológicos de cada processo. Não foram identificados titulares do Brasil, conforme os critérios e as fontes adotadas no estudo. A metodologia empregada mostrou-se útil para a obtenção dos resultados pretendidos e abre espaço para o seu aprimoramento mediante novas pesquisas.

Aug 8, 2018

By F. E. Block, Stephen D. Hill

The necessity for measuring radiation dose is encountered in studying both the beneficial and damaging effects of ionizing radiation on materials . It is also necessary to know the radiation dose absorbed by the reactants in order to evaluate the efficiency of reactions or processes that are promoted by radiation . Thus , a significant effort was made at the Albany cobalt 60 facility to investigate techniques by which the exposure radiation dose can be determined . Methods including ferrous sulfate , ceric sulfate , and methyl methacrylate chemical dosimeters , ion chamber dosimetry , and an absolute radiation calorimeter were investigated . Isodose curves were constructed for several standard source configurations using the dosimetry techniques which were investigated .

Jan 1, 1964

By Milson de Andrade Júnior

A central termoelétrica número 1 (CTE#1) da Companhia Siderúrgica Nacional possui duas caldeiras em operação denominadas 8 e 9 com capacidade total de produção de vapor de 200 Toneladas por hora. Estas caldeiras fornecem vapor para os turbo geradores e turbo sopradores da CTE#1, além de vapor de processo para a Usina Presidente Vargas (UPV). As caldeiras entraram em operação em 1982/83 e seus sistemas de controle e instrumentação eram totalmente pneumáticos. Ao longo do tempo foi surgindo dificuldades para reposição e manutenção dos componentes pneumáticos, motivo pelo qual se iniciaram os estudos para substituição deste sistema. Em 2009 teve início um projeto para substituição do controle pneumático por um controle microprocessado feito por PLC redundante trabalhando com um supervisório scada e para substituição das malhas de instrumentação pneumática por instrumentação em rede fieldbus. A substituição completa dos componentes pneumáticos foi concluída em 2012. O novo sistema implantado trouxe diversas melhorias na performance, confiabilidade, segurança operacional e ergonomia. Este trabalho apresenta as causas que motivaram o projeto em questão, a metodologia utilizada para a sua implantação e os resultados alcançados com a aplicação de tecnologia moderna para controle e instrumentação de caldeiras.

Jul 31, 2018

By D. V. Roberts

Approximately 800 private consulting engineering firms in America specialize in geotechnical engineering. The gross income from these firms totals about $500 to $600 million per year. Sixty-five to seventy-five percent of this geotechnical work is per­formed by consulting engineers that belong to the Association of Soil and Foundation Engineers (ASFE). This paper presents statistics concerning the business activities and functions provided by ASFE member firms. The procedures used in typical projects are described. The paper concludes with a summary of major trends which are impacting the American geotechnical practice today.

Jan 1, 2010

By Perry Olcott .

THE Taka oil field is in the northern part of Titus and Franklin Counties, in north- eastern Texas. The small town of Talco, from which the field derives its name, is on the P. & Mt. P. R. R., about 15 mi. north of Mt. Pleasant, the county seat of Titus County. The oil field extends east and west from the town of Talco, the approximate center. In May, 1924, R. L. Cannon, while doing surface geology for the Humble. Oil & Refining Co., mapped the surface trace of this fault structure as evidenced by Upper Midway faulted down against Lower Midway. In the interval of sixteen years between the original surface work and the recent productive well completion, approximately eight wells were drilled into the Woodbine sand without success. The structure was well defined by those tests and all of the wells en-

Jan 1, 1936

By Christopher Mark

This proceedings volume contains papers presented at technology transfer seminars sponsored by the National Institute for Occupational Safety and Health (NIOSH) on New Technology for Ground Control in Retreat Mining. The seminars were conducted at five locations: Uniontown, PA (March 26, 1997), Norton, VA (April 8, 1997), Pikeville, KY (April 10, 1997), Charleston, WV (April 17, 1997), and Evansville, IN (April 22, 1997). The papers presented here describe several new, highly practical technologies developed by the NIOSH Pittsburgh and Spokane Research Centers3 to improve safety during pillar retreat operations. Two central issues are addressed: pillar design and mobile roof supports (MRS's). Proper pillar sizing is essential for safe pillar extraction. The Analysis of Retreat Mining Pillar Stability (ARMPS) program and its large data base of actual mining case histories are presented. LAMODEL, a second computer program, can be used for analysis of multiple-seam and other complex mining situations. Other papers address pillar design to avoid massive pillar collapses and the proper role of coal strength testing. MRS's have greatly improved safety where they are used for pillar line support. We studied the application of MRS's at 20 mines throughout the Eastern United States. Conclusions regarding the most effective section layouts, cut sequences, and support placements are reported. Field and laboratory tests of MRS's are also described.

Jan 1, 1997

By Howard S. Avery

The wear resistance of an alloy in heavy mill liner sections may be quite different from that of the same alloy in small balls and other light sections. This fact was established by means of a well standardized laboratory test that was validated for ball mill service. The salient properties of mill liner alloys, including austenitic manganese steels, medium alloy hardenable steels, and abrasion resistance cast irons are described, critically compared, and quantitatively ranked in terms of mill liner service. Where they are tough enough the high-chromium and other martensitic cast irons (e.g. Ni-Hard) promise maximum economy, but their section sensitivity is a limitation. To overcome this an extensive research program studied over a hundred experimental alloys, ranking them for heavy section abrasion resistance by means of the laboratory test. Computer analysis of the results provided a parabolic formula in terms of composition, the apexes of the parabolas providing optimum wear resistance. From the extensive family of parabolas one apex was selected for intensive study in experimental liners, pilot plant production, development of quality controls, and finally full scale production. This is a 19% chromium iron critically alloyed with nickel and molybdenum and hardened by heat treatment. It has excellent resistance to various types of abrasion, but its chief advantage is in heavy mill liner sections, where it has about 25% better abrasion resistance than the best of the quality controlled chilled Ni-Hards. It is also tougher. After production problems were solved, a number of ball and rod mill tests were arranged on a guaranteed performance basis. Two of these, representing about 138,000 pounds of mill liner castings, have recently confirmed in service the superiority that was predicted by the laboratory tests.

Jan 1, 1969

By R. Drozd

"The Bui/moose Mine is in the northeast coal area of British Columbia, and less than $300 million was spent to bring this 2.3 million-tonnes-per-year metallurgical and thermal coal mine into production by November 1, 1983, one month ahead of schedule. The project is an unincorporated joint venture undertaking, with Teck-Bullmoose Coal Inc., a wholly-owned subsidiary of Teck Corporation, holding 51%, Lornex Mining Corporation holding 39%, and Nissho-lwai (Canada) Ltd. holding 10%. Bullmoose Operating Corporation will be the manager and operator of the project. This paper will broadly cover the history and exploration work on the property, the geology, open-pit mining plans and equipment, the preparation plant flowsheet from breaker station to clean coal silo, the 35 km highway truck haul, the railroad loadout system, manpower requirements, approvals and permits, and general financial arrangements. Introduction The Bullmoose Mine Project is located about 87 km by road south of Chetwynd, B.C. and consists of an open-pit coal mine, a plant facility in the Bullmoose Creek valley below the mine, and a separate rail loadout facility on the British Columbia Railway Branchline near the new town of Tumbler Ridge some 35 km by road to the east. The plant will be capable of producing a total of 2.3 million tonnes per year (mty) of washed metallurgical and thermal coal. Long-term metallurgical coal contracts for high-quality, medium-volatile, bituminous coal have been signed with nine Japanese buyers for 1.7 mty, and the balance of0.6 mty will be for thermal coal production. Plant construction began in the spring of 1982, and in May 1983, preproduction waste and overburden removal in the mine was started. The plant began tuning up in October and was fully operational by December 1983. Metallurgical coal began moving to the coast in unit trains during November, and first vessel loading at the Ridley Island port began in late December 1983."

Jan 1, 1985

By Christos Roumpos, Philip‑Mark Spanidis, Francis Pavloudakis

Coal mining operations are large-scale, long-term frameworks of high complexity. Mining organizations accumulate, develop, and leverage knowledge from diverse scientific and technological fields as a result of these operations. Both practical experience and existing literature indicate that knowledge management (KM) methods within the mining industry primarily target solving immediate technical challenges and operational requirements. However, they are not commonly regarded as strategic tools to enhance the performance and competitiveness of mining companies. Empirical evidence from the Greek mining industry suggests that the management of available knowledge is intricate, less effective, and dysfunctional. This paper presents a methodology based on the principles of quantitative research (QNR), collaboratively conducted with a group of mining experts, to assess the KM landscape in the Greek mining industry. The methodology involves a structured data collection framework using questionnaires, subsequent statistical analysis, a discussion on critical methodological aspects, and an interpretation of results focusing on key aspects useful for planners and designers of KM systems in the mining industry. Finally, the paper concludes by summarizing the methodology’s outcomes and proposing further perspectives for research.

Mar 16, 2024

By R. Lawrence

Mineral property valuations to be used for Canadian securities regulatory purposes must comply with CIMVal1. The technical basis for a CIMVal report is the same as that required for a technical report that complies with NI 43-1012. NI 43-101 describes the content to be covered in a technical report, while also covering other requirements, one of which is that the report should be based on a property visit. CIMVal is based on five tenets that the valuator must follow: ? Materiality. ? Independence. ? Transparency. ? Competence. ? Reasonableness. Upon its adoption by CIM Council in 2003, it was hoped that the new CIMVal code would be adopted without change by the several Canadian regulators.

Jan 1, 2011

Jan 1, 2004

By J. P. Morris

A diphenyl ether calorimeter for measuring high-temperature heat contents of ferrous alloys and iron-and steelmaking slags was constructed and calibrated with specimens of molybdenum, alumina, and platinum that were heated to temperatures ranging from 1,720° to 1,875° K. The standard deviation of the calibration measurements was 0.37 percent. By measurements of the enthalpy of delta and liquid iron, the heat of fusion of iron was found to be 3,298 ±100 cal per mole.

Jan 1, 1966

By B. Solar Menéndez, M. B. Díaz Aguado, I. Á. Fernández, C. González Nicieza

The analysis of subsidence due to the opening of an underground void (mining, water exploitation or civil works hole) is a problem usually hard to solve. First of all, it requires a predictive model, in order to define both the displacement magnitude and area affected by subsidence. Such model should be validated with measurements of the actual movements sustained on the surface, in order to adjust it properly and enable influence of future behaviour in a reliable way. Two different kinds of problems might arise. On one side, it is necessary to control and measure surface movements in a very exhaustive way during a long period of time, beginning before underground works take place and finishing years after they are over. Furthermore, three factors bring in errors, some times of magnitudes higher than the displacement magnitudes measured. These include: the fact that reliable and long-term information cannot always be achieved; the precision of measuring devices; and the design of the topographical network itself. In addition, the predictive models more widely used only apply to certain excavation geometries, mainly to horizontal holes. In light of this background, the Group of Rock Engineering, of the University of Oviedo Mining Department, has developed a working methodology and a specific software tool, Subsidence 3D, to estimate ground displacements and strains. The program will allow for predictive models to be defined and also allows the treatment of data related with topographical marks and its comparative analysis with calculated results. The software has been programmed using Visual C++. Graphical outputs however are generated using AutoCAD 2000. This paper mainly refers to a practical situation, an underground coalmine, remarking the main difficulties arisen during the study of the available information and proposing how to solve them. A predictive model in subsidence 3D was established and validated. The actual behaviour of the ground was that in the model.

Jan 1, 2003

By R. K. Borden

Rio Tinto is committed to proactive mineral waste and acid rock drainage management. Corporate requirements are closely aligned with the GARD Guide principles of early geochemical characterization and prediction followed by selection and implementation of management strategies to prevent or minimize ARD. Each operation is required to design and implement an ARD and Mineral Waste Management Plan. Successful implementation of the plan requires commitment at all levels of the company, from senior management, to geologists, mine planners, environmental staff and equipment operators. Examples of the successful integration of ARD management strategies into mine operations are cited from several mines.

Jan 1, 2011

By Ray Wood, Rene Sterk, Robin Falconer, Sean Aldrich, Simon Nielsen

"The Chatham Rock Phosphorite project is situated 450 km east of New Zealand at approximately 350 to 450 m water depth. The deposit occurs as a thin layer of phosphatebearing glauconitic sand at the surface of the sea floor and has a thicknesses typically ranging from 0 to 1 m. The sand layer consists of mainly silt and sand-sized sediments, with phosphatised chalk nodules up to 15 cm in diameter. Phosphate nodules were first discovered on the Chatham Rise in the 1950s by a New Zealand Government survey. During the 1960s to 1980s several private and government sponsored cruises explored the Chatham Rise and surrounding seafloor area. A total of 1174 samples were collected over a 600 km2 area with the majority of the samples collected using a pneumatic -or large Van Veen-style grab-sampler.Since acquiring the licence in 2010, Chatham Rock Phosphate Limited has conducted six cruises in two programs in the Project area. A total of 261 samples were collected using a Van Veen grab, box core and grab samples.Sample quality and QA/QC measures varied considerably between the cruises and within each cruise. A critical part of the assessment of the data collected in the Project area was to determine what quality thresholds to use to allow or disallow data to enter into the estimation process. As part of the data verification process, the relative and absolute quality of the data was assessed in as much detail as practically possible. The best samples were those that were collected using the pneumatic grab, sampled the full sand horizon, had a small location survey error and had no other apparent data ambiguities. This paper describes the challenges for mineral resource estimation for an unconventional style of mineralisation using unconventional sampling techniques."

Sep 1, 2014

By R. J. Sweigard, C. T. Justice, T. Beckham, E. D. Thompson, T. C. Hopkins

Fine coal refuse is often pumped, as slurry, into surface impoundments as a means of permanent disposal. As the available volume is filled, the height of the embankments are frequently increased. Many times the additional embankment material is placed upon consolidated fine coal refuse. There has been some concern about the long-term effect of consolidation of this material at or above the liquid limit upon its shear strength. A laboratory investigation was performed using three different types of fine coal sluny taken from Central Appalachian coal preparation plants. The refuse was consolidated in 10-foot plexiglass columns under incremental amounts of surcharge loading. The incremental loads were designed to simulate the effect of increasing the height of a refuse embankment on top of the consolidating coal slurry. After the refuse in the columns had consolidated for several months, the columns were cut apart and triaxial tests were performed on both the consolidated material and unconsolidated material for comparison of their shear strength parameters.

Feb 24, 1997

If the industry keeps doing what it has always done, it will continue to get what it has always got - rising operating costs. Why is this so? Generally grades being chased are becoming lower, stripping ratios becoming higher, ability to attract personnel to the industry becoming harder and/or more expensive, higher safety standards are being demanded and environmental governance is being enforced.   How then should the surface mining industry plan for the future whilst delivering on improved safety and the environment? In-pit crushing and conveying (IPCC) points the way, as a partial or complete substitute for trucks.   IPCC systems promise significant advantages over traditional truck and shovel operations, including improved safety, reduced operating costs, reduced dust and noise emissions, far greater efficiency in energy use (electric versus diesel motors predominantly and the ability to regenerate electricity back into the local grid for downhill situations), reduced carbon emissions (dependent on power generation source) and reduced water consumption. Despite these advantages, there is a general industry reluctance to migrate from truck and shovel operations. This reluctance stems from a familiarity with truck and shovel operations and a perceived concern that IPCC lacks flexibility which will negatively impact on the mining operation.   In studies conducted since 2007 (with the new modular builds) comparing IPCC with truck-optimised pit designs, IPCC has delivered up to USD$0.82 per tonne moved less than an equivalent truck operation. In addition, IPCC is easily automated from a central control room (local or remote) - something that trucks have yet to commercially achieve.   IPCC is a proven process that, with a fresh mindset, can make a significant improvement to mining operations - its safety, the impact on the environment and its costs. It maybe of interest to note that there is over 200 IPCC installations worldwide today.   This paper and presentation will assist in furthering the understanding of IPCC and its applicability.

Jun 1, 2010

By Courtney Chamberlain

The Telfer Project, Australia's newest, largest and most remote gold mine, treats 480,000 metric tonnes of ore grading 9.33 grams per tonne derived from open pit mining operations. Coarse gold is recovered by gravity concentration with jigs and further upgraded using a continuous strake, table and by amalgamation. Remaining gold is recovered in a cyanide circuit and incorporates flat bottom air agitators, CCD and stellar filters for clarification and precipitate removal. Overall recovery into bullion averages 98 percent. The mill incorporates a number of design features which allow for maximum efficiency and security using a minimum number of operating personnel.

Jan 1, 1980

By James S. Browning

The Bureau of Mines conducted laboratory batch and small-scale continuous selective flotation tests of barite-fluorspar ores from two deposits near Marion, Ky., to determine the technical feasibility of recovering commercial grade fluorspar and barite concentrates. The lignin sulfonate-sodium fluoride method of floating the fluorspar successfully produced acid-grade fluorspar concentrates. Flotation of the barite from the fluorspar tailing using petroleum sulfonate collector yielded concentrates suitable for use in compounding oil-well drilling mud. The fluorspar and barite recoveries were about 82 and 85 percent, respectively.

Jan 1, 1963