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By Mike Cammack, Logan Huppert, Gustavo Azpilcueta

During the summer of 2015, Unisea Inc. sought proposals for the G1 Dock Replacement Project in Dutch Harbor, Alaska. It would be a one year project and construction was scheduled to begin in the spring of 2016. One aspect of the project was the requirement for a layer of armor stone to protect part of the dock. An estimated 30,500 tonnes (37,670 t) of armor stone were needed for the project. The source of rock was the Unisea Quarry due to its proximity to the project and the quality of the stone meeting all the required technical standards.

Jan 1, 2018

By Shemek Oginski

The 5 km (16,194 lf) of 6.1m (20 ft) diameter TBM driven tunnel built by the J.F.Shea Co. will serve as sewage overflow storage. The TBM tunnel and four connecting tunnels excavated by drill and blast methods in hard granite will remain unlined. Based on the Geotechnical Baseline Report (GBR), the Contract documents provided a design with no required pattern of rock bolts, no probing, no pre-excavation or consolidation grouting, and lastly, no final lining of the tunnels was deemed necessary. This paper will provide a general overview of these topics with the emphasis on the actual ground conditions encountered versus the projected conditions provided in the GBR and how the GBR reflected the design of the project. Proposed modifications to the temporary and permanent ground support will be presented and the necessity of probing and pre-excavation grouting will be evaluated.

Jan 1, 2005

By Paolo Cavalcoli, Marco Ziller

"ABSTRACT: In the year 2010 the State of Denmark together with the Municipality of Copenhagen, launched a very important and complex Project : the complete construction of a new double Subway Line :the CITYRINGEN.Copenhagen is the capital with a metropolitan population of 1,9 million.This line is like a ring placed in the very town center which includes all the most historical and monumental buildings and churches, with a total length of 17 km, and the presence of 17 stations plus 4 service shafts.The buildings have been built in the last centuries in an area where the groundwater is near to the surface and there are lakes and channels: the techniques adopted were advanced for those times, but limited as far as regards settlements and resistance to horizontal movements.The soil consists in 2 main groups.1.Upper sediments of the glacial ages : thickness total = 5-20 m composed by clay- silt-sand-gravelcobbles- granite boulders and flint in blocs and in layers : frequency and size of these obstacles wherenot determined.2.Limestone layers : 2a. upper limestone : highly fractured ,highly permeable2b.Itermediate limestone : less fractured, medium permeability.2c. Lower limestone : almost not fractured, low permeability.2d Bryozoan limestone : composed by fossils with microscopic dimensionsIn all the limestone formations there are important layers of flint , having thickness variable up to 3 m and important extensions. Water : in a part of the areas of the Cityringen the water is drinkable and utilized in the public waternet.Pollution: there are polluted zones due to previous industrial activities. Benzene areas have been identified, and for those areas special protections against pollution have been implemented.METROSELSKABET ,the public owner of the Cityringen,has set as priority to operate for the construction of the Cityringen the full protection of the environment and the respect of all the stakeholders :Very strong limits for the exhausted gas emissions have been introduced, by far stronger than those applied from the State of Denmark, very strong limits for the acceptable noise emission. And last but not least very important safety measures and procedure to avoid any accident on site."

Jan 1, 2014

Supplement to Proceedings Number 120, December, 1940. Drawings accompanying paper by T M Carey 'The Surface Plant at the Zinc Corporation Mine, Broken Hill'

Jan 1, 1940

Effect of Spacer Chain Length on the Flotation of Kaolinite and Quartz by Using Gemini Surfactants as Collector

Sep 13, 2010

By John E. Wiegand

This study will discuss the AMAX Coal Co., Penndiana Pipeline Project, which was conducted in conjunction with the following parties: AMAX Coal Industries, (U.S.B.O.M.) United States Bureau of Mines, (I.D.O.R.) Indiana Division of Reclamation, Ohio Valley Pipeline, Inc., New Mexico Tech, and ourselves, VIBRONICS, INC., Evansville, Indiana. The purpose of this study was to find a safe vibration level for active gas transmission pipelines near surface coal operations.

Jan 1, 1994

Increasing demands on quality of metallurgical grade alumina and for lower production costs led to the development of a new fluid bed calcining process. The process, jointly developed in Germany by Vereinigte Aluminium Werke A. G. and Lurgi Gesellschaften m.b.H., takes advantage of modern chemical engineering methods such as counter-current flow of combustion air and solids, direct heat-exchange between combustion air and fine solids, and near stoichiometric combustion of oil in a fluid bed. Using a two-stage Venturi-type suspension preheater for heat-recovery from combustion flue-gases, the circulating fluid bed technique with internal oil combustion at 220°F for the calcining step and a five-stage fluidized bed cooler for heat-recovery from calcines, the process gives an outstanding heat-efficiency. In a first industrial plant for 560 sh. tons/day of alumina heat consumption figures of less than 1·400 B.T.U./lb Al203 g were achieved.

Jan 1, 1972

By B. A. Comley

Over the past few decades a great deal of effort has gone into characterizing the effects of frother type and concentration in flotation using a variety of two-phase techniques. Whilst useful and informative, this research still does not assist in the selection of suitable frothers for three-phase industrial-scale froths. This paper investigates the effects of frother type and concentration in a three-phase industrial froth. The objective was to determine if progress could be made in terms of understanding the behavior of frothers in flotation and understanding how they affect the sub-processes occurring in the pulp and froth phases and, ultimately, the metallurgical performance of a flotation cell.

Jan 1, 2007

Laboratory-Scale Magnetohydrostatic Separator for High Resolution Density Analysis of Plastic and Other Wastes Recycling and reuse of different plastic wastes is still a current problem to solve for process engineers and it is true for seeking industrial applications as well as for smaller laboratory-scale, where a given waste sample, plastic or even metallic, has to be precisely separated into narrow density fractions to gain data for industrial design or for scientific research. The principle of magnetohydrostatic separators are known even there are industrial size machines but our primary aim was the development of a laboratory-scale separator for analysis of particles of densities up to 6 kg/L and sizes up to 8 mm. Main parts of the built experimental equipment are the ferrite core with two high power coils. The shape of the ferrite core at the two sides of the separator channel was specially designed to produce isodynamic magnetic field. In these places the ferrite core was constructed from laser cut ferrite sheets. The development of the high power electric supply for the two coils was a real challenge because the high voltage and current (400 V, 30 A) and because it had to be precisely regulated for being able to set discrete relative forces on the particles. Two separator channels were made from transparent plastic. The magnetic fluid is circulated by a centrifugal pump, fresh feed is supplied by a vibrated feeder and products can be taken by built in samplers. The velocity profile in the separator channel is measured by an ultrasonic Doppler velocity meter. Paper reports about the development and itself of the magnetohydrostatic separator and about some fundamental and applied laboratory experiments with different reference particles and wastes from used cars and electrical appliances.

Sep 13, 2010

By R. W. Baker

"The development of uppers drilling at Brunswick Mining is reviewed. This paper describes design criteria for drilling patterns and the research required for selection of a suitable drill jumbo. The success of the uppers drilling program based on operating procedures is highlighted. IntroductionBrunswick Mining and Smelting Corporation Ltd., operates a 10 500 tonnes per day lead /zinc/copper I silver underground mine some seventeen miles southwest of Bathurst, New Brunswick .The No. 12 orebody, first discovered in 1952 by a group headed by M.J. Boylen, had extensive development, including two shallow shafts (500 ft), and test work carried out on it by St. Joe Lead between 1953-1957. However due to complex metallurgy and depressed metal prices, the operation was suspended.In 1961, a group comprised of M.J . Boylen, K.C . Irving and Patino acquired the rights of St. Joe Lead to the No. 12 property. A concerted development plan was initiated along with construction of the necessary sur face facilities and by July 1964, the property was in production at 4500 tons per day.In 1967 Noranda Mines Ltd. acquired operating control of Brunswick Mining and Smelting Corporation Ltd."

Jan 1, 1988

By Marcía García

El presente texto revisa la historia minera de Morococha. Aunque no se tienen datos exactos sobre el inicio de la explotación de esta minera, existen indicios primitivos de este proceso antes de la llegada de los españoles. Durante el Coloniaje se comenzaron a trabajar minerales oxidados que se beneficiaban por amalgamación en «circos»; asi como las galerías y pavonados que se fundían en horno de «pachamanca». Posteriormente, don Martín de Bidegaray, minero, azoguero y hacendado, solicitó licencia para levantar un Ingenio (Molino de metales) en el paraje San Martín de Tuctu de Morococha. El virrey le concedió y se construyó el molino de metales, constituyéndose la partida de nacimiento de la industria metalúrgica en Morococha y toda la región central del Perú. Sin embargo, la lucha por la Independencia Nacional paralizó por completo la naciente industria minera del Coloniaje, quedando en abandono las labores de extracción de minerales, sumándose la escasez de barreteros. Por ello, el señor Izcue, recurrió a Carlos Pflucker, hombre enérgico y emprendedor, quien pronto se convierte en el pionero de la Pirometalurgia al tratar de fundir minerales de cobre en hornos de Reverberación construidos por tres operarios fundidores traídos por él especialmente de Alemania. Finalmente muere el señor Izcue y Pflucker decide contratar más barreteros y convirtió a Morococha en una próspera Hacienda Minera, descubriendo nuevas minas de plata e instalando modernos procesos metalúrgicos de amalgamación y cloruración en Tuctu. Así, en 1905 el señor James B. Haggin adquirió las propiedades de la Compañía Minera de Santa Inés Y Morococha, y en el año 1908 por acción de los señores Haggin y A. W . McCune se constituyó la Morococha Mining Company, entidad de la que también formaron parte integrantes los miembros de la Cerro de Paseo Syndicate.

Nov 1, 1964

By Helmut Hass, Marco Ziller

"Abstract: 1 Sophia Spoortunnel Marco Ziller, Trevi S.p.A.:For the construction of 14 cross passages connecting the twin tunnels of the Sophiaspoortunnel the Artificial Ground Freezing technique was applied as temporary soil improvement. AGF by Brine and Liquid Nitrogen was implemented. Automatic data acquisition and recording systems were installed to monitor the variation of the temperatures in the soil during the freezing intervention in order to control the behaviour and the efficacy of the treatment.IntroductionThe Sophia rail tunnel is a bored tunnel with a length of 4.24 km, comprising two separate parallel tubes with an outside diameter of 9.45 m. The twin tunnels were excavated by a TBM equipped with hydroshield. Seven service shafts, approximately 30 m deep, were constructed in between the tunnels. From each shaft two cross passages were constructed connecting the shaft with both tubes, for a total of 14 cross passages.The Artificial Ground Freezing technique utilizing both the Brine and Liquid Nitrogen methods was used for temporary waterproofing and soil support to allow the excavation of the cross passages. The natural soil to be frozen was consisting in loose sand and clay under a hydrostatic pressure up to 250 kPa.For the measurement of the ground temperature. Automatic data acquisition and recording systems were installed to monitor the variation of the temperatures in the soil and at the contact with the tunnel lining. Furthermore, a comprehensive computerized system of sensors and cryogenic valves was designed and implemented in order to manage the whole Nitrogen process.Soil Main CharacteristicsThe soil stratigraphy is generally consisting in Clay (Holocene) from ground level to -15 m depth, followed by Pleistocenic Sand, from -15 to -25 m, and Clay below -25 m."

Jan 1, 2014

"This paper reviews the chemistry involved in the recovery of gold from cyanide solution with anion-exchange resins, and also discusses the most critical aspects of the engineering of an effective resin-in-pulp (RIP) process. As far as the chemistry is concerned, the conclusions reached by a great many researchers, as well as the performance of the only operating RIP plant in the Western World, at the Golden Jubilee Mine in South Africa, support the view that the process is technically viable and, in many cases, could prove to be more attractive economically than alternative processes such as zinc cementation and carbon-in-pulp (CIP). On the engineering side, there is still a need for further development before larger scale ( > 50,000 tpm) RIP plants can be designed, built and operated with confidence. However, the experiences gained during nearly 3 years of operation of the Golden Jublee RIP plant indicate that the process can be engineered with confidence for smaller operations ( < 50,000 tpm), and this will probably be the scope of application of the first-generation RIP plants. INTRODUCTIONThe use of anion-exchange resins in gold processing has, for a number of years, been proposed as an alternative to more conventional processes such as zinc cementation and carbon adsorption, and detailed research programs that have been carried out at a number of laboratories have demonstrated the technical viability of the process. (Burstall et al, 1953, Davison et al., 1960, Tataru, 1973, Laskorin et al. 1978, Hosking, 1984, Riveros and Cooper, 1987 and Palmer et al., 1988)The main incentive for this work was the fact that resins have several characteristics that are quite different from carbon, which make them potentially more attractive substrates for the recovery of gold. The following are examples: -"

Jan 1, 1991

By Ernie Doell, Trung Nguyen

"In early 1995 Cluff Mining commissioned a newly constructed high density tailings thickener at its Cluff Lake uranium mill. The 85 ft diameter high density thickener is one of the first of its kind in North America, and incorporates the novel paste technology in its design to produce densified (in the range of 60 -65% solids) mill tailings suitable for stable deposition in the tailings management area. This paper discusses the impetus behind the installation of such an unconventional thickener, and the many trying experiences in making it operational.IntroductionCluff Mining, a wholly owned subsidiary of Cogema Resources Inc., is the operator of a uranium mine and mill complex at Cluff Lake which is located in northern Saskatchewan. Since 1980, the company has developed and mined out several different ore bodies within the Cluff Lake region for the production of uranium concentrates, commonly known as yellow cake. Based on the known ore reserves, the Cluff Lake operations are projected to last till the early 2000's.Tailings from the Cluff Lake mill have been discharged to a tailings management area consisting of a tailings pond and two facilities for primary and secondary treatment systems. The tailings pond has an impervious bentonite lined dam, and it is divided into a solids and a liquids holding areas. Until the beginning of 1995, the mill tailings were discharged in two separate lines to the solids pond; one line carried the slurry residue of 45-50% solids (w/w) from the CCD circuit, and the other discharged raffinate tails containing less than 1 % (w/w) gypsum precipitate. Supernatant in the solids pond is treated in the primary treatment system prior to discharging to the liquids pond. Figure 1 shows the site plan of Cluff Lake tailings management area.It has been estimated that by the end of 1995 the solids pond would be filled to about 60% of its design capacity, and probably would be full before the year 2000. Therefore, Cluff Mining had to consider a more efficient tailings disposal method that could extend the service life of the existing Cluff Lake tailings management area. A high density tailings thickener was believed to be the most practical and economical system for tailings disposal at Cluff Lake mine."

Jan 1, 1996

By Dale Dean, Bill Hancock, Raul Mondragon, Carlos Aguilar, Chris Martin

"In 1942, commercial mining operations began in what is now the Lucky Friday Ag/Pb/Zn mine in Idaho’s Silver Valley. Wholly owned since 1962 by Hecla Mining Company, the mine has produced more than 145 million ounces of silver and has been a mainstay producer in Idaho’s Silver Valley for over 70 years.However, by the early 21st century, the mill had fallen, technologically, seriously behind the rest of the industry. Accordingly, starting in 2005, the current mill management team set to revitalizing the milling operation. This paper will describe how the mill was systematically evaluated and the aging infrastructure replaced with more current technology. Driven by internal mill review studies supported by QEMSCAN mineralogical balancing, the mill has in recent years been through waves of upgrading – from the installation of new mechanical and column flotation equipment to the introduction of on-stream analysis, a technology well-accepted around most of the industry but alien to this technologically conservative mining district.The experience at Lucky Friday is a testament to the need for ongoing structured mill optimisation and technology upgrading in established mining operations. This paper will describe engineering experiences associated with upgrading equipment in an operating mill, contained in a confined building. Experiences in teaching the team new ways of operating a mill, and finally the metallurgical rewards that have been reaped will be described.INTRODUCTIONMining in Idaho’s Silver ValleyIdaho’s Silver Valley is a 64-km long valley flanked by the US Northern Rocky mountains, seldom more the 3-km wide, and stretching across much of Idaho’s northern panhandle, roughly 150 km south of the Canadian border. Mining has been continuously active in the area for more than 140 years, during which time, the Silver Valley has become one of the richest silver producing districts in the world, and as of 1985 had out-produced the 500 years of production from the famed Potosi district in Bolivia. Since 1885, almost 100 deposits have been discovered and worked in the district (Chapman, 2000)."

Jan 1, 2011

By É. Roberge, S. Makni, G. Gagnon, F. Lavoie, A. Faucher

"Feed particle size is an important variable for the primary grinding mill operation. Several commercial vision systems have proven to successfully measure online many types of ores and are used for automatic control. However, due to limitations associated with segmentation algorithms, these systems fail to provide good measurements when the feed is composed of a specific bimodal particle size distribution: very big rocks and a large amount of fine particles. This is typically the case for crushed iron ore. This paper presents a technique to overcome the limitations of existing vision systems by using 3D cameras and appropriate processing methods. It provides online particle size distribution indicators and bulk volume flow rate measurement. It is designed to be very cost-effective, robust, precise, easy to install and to maintain. The 3D system was validated in two iron ore processing plants and the results clearly show that it can be used to optimize primary grinding mill operation where 2D segmentation vision systems fail.INTRODUCTIONFragmentation measurement using digital image processing has successfully been applied in mining and mineral processing operations. Several maintenance and operating applications are already deployed in the industry: Measurement of rock fragmentation after blasting (Maerz, 1999; Palangio, 1999) (Pragyan, 2012) Truck inventory (Palangio, 2005) Monitoring of crusher mantle wear Automatic control of crushers and SAG mills (Bouajila, 2000) (Bartolacci, 2001)Commercial technologies like WipFrag (Maerz, 1999), VisioRock and others proved to be very efficient to precisely measure the particle size distribution of many types of materials. These products are mainly composed of a camera, a lighting system and an image processing system based on a segmentation algorithm. By controlling adequately the lighting conditions and with periodic maintenance on the segmentation algorithm calibration parameters, it is almost always possible to achieve reliable measurements.However, the segmentation algorithm is not adequate when the particle size distribution contains big rocks and a large amount of fine particles. In this case, the area containing the fine particles is accounted as a big rock while big rocks get segmented as multiple smaller sized particles, leading globally to a wrong measurement. This situation prevails for crushed iron ore and coke, among other materials. Figure 1 shows a picture of a material which is typically very difficult to process through segmentation techniques."

Jan 1, 2015

By Rodrigo Toro, Mario Delisle, Claudio Zamora

"The mining market is researching innovative methods to train the workforce for mining which is normally extremely difficult to get. Thus, the dynamic simulation-based technologies become an essential pillar to educate and train the inexperienced staff at the pace required by this industry. Even if Operator Training Simulator (OTS) systems are commonly used in most of industries, knowledge transmitted to operators are unfortunately not ""capitalized"" in general. The OTS systems are usually delivered as a single hardware and software platform and very little as a full service long-term.In this article, an integrated solution to increase the efficiency of the operators is proposed. This solution is based on the combination of dynamic simulation, processes knowledge, virtual reality and the knowledge capitalization through the creation of simulation scenarios and e-learning. The Codelco Ministro Hales plant simulation project for a copper concentrator plant is presented as a real life example.IntroductionDynamic and real-time process simulation have proven to be a must in the development of greenfield projects, providing mechanisms to design and test controls design, interlocks, start-up, shut down sequences and operator training, among others (see (McMillan, 2006) for further details). Early adopters of this technology were utility power plants; in the petrochemical industry have become a standard, and in the mining industry the use of dynamic simulations is growing, especially in new projects and training of operations personnel for the adoption of best practices and new technologies, see (Nikkhah & Anderson, 2001) and (Toro, Ortiz, & Yutronic, 2012).This paper outlines a solution that utilizes dynamic simulations as the base of an integrated platform for operational effectiveness, which takes into account the current scenario of new mining projects and operations, where high turn over rates and needs of specialized workforce have given a special value to this kind of technologies."

Jan 1, 2015

By Iván Zevallos

"La mina de talco localizada en el estado de Río Grande del Sur (Brasil) fue explotada hasta agotar sus reservas. En ese sentido, para descartar la existencia de algún cuerpo del mismo mineral en las proximidades se propuso efectuar una prospección magnética terrestre. La asociación del talco con esquistos magnesianos y serpentinitas confiere validez al levantamiento geofísico, debido a la alteración de los esquistos que los torna ferromagnéticos, de forma que se determina que el yacimiento fue explotado. En ese sentido, el presente texto describe el levantamiento magnetométrico como método magnético para determinar el cierre de una mina de talco como importante precedente para los exploradores de yacimientos de minerales no-metálicos."

Dec 1, 2016

By Beverly Cramp

In 1995, mining engineer Alain Gachet thought about using Earth-observation satellite imagery to search for precious minerals. The latest radar Earth-observation satellite, Canada’s RADARSAT-1, had just been successfully launched at the time, creating new opportunities for commercial applications. Gachet was working in Congo Brazzaville as an oil executive and general secretary of Elf Congo for the French national oil company Elf Aquitaine. He understood that the RADARSAT-1 launch promised new and cost-effective sources of data for mineral and oil exploration. “It was early 1996 before I ordered my firstRADARSAT-1 satellite images,” said Gachet. “I was first struck by the quantity of information delivered by the radar images. Linear structures and faults were clearly defined and subtle topographic features were tremendously enhanced,” he said. “It was ‘tree top geology,’ but this kind of information appeared to be key for finding new gold seams.”

Jan 1, 2003

By H. Kenworthy

This report concerns cooperative milling investigations of the Central mill of the Eagle-Picher Mining &. Smelting Co, The work carried on at the Central mill and the Rolla, Station shows that: It is possible to reduce the Central mill heavy-medium plant tailings by 0.05 to .15 percent zinc; the 3/16-inch to 10-mesh fraction of the jig feed can be treated by sink-float to obtain a tailing containing only half as much zinc as the jig tailing; Humphreys spiral concentration of the flotation tailing does not recover enough zinc to be economically attractive; and crushing and wet grinding of ferrosilicon for heavy medium are commercially feasible. The Eagle-Picher Co. operates extensive mines in the Tri-State area of Missouri, Kansas, and Oklahoma. The ore is milled at its Central hill, which also accepts custom ores. During the recent war the mill handled about 12,-000 tong- of low-grade ore per day. The company milled about 50 percent of the district tonnage and purchased nearly 90 percent of the custom ore. About 50 percent of the mill feed was from company mines. Zinc is the chief value in the Tri-State ores,-with Varying quantities of lead and cadmium minerals, as well as small amounts of germanium and gallium.

Jan 1, 1949