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By G. Taylor

"The Iron Ore Company Of Canada's Carol Project is located in Labrador City, Newfoundland. Labrador City is some 912 air kilometers northeast of Montreal, and 417 ratl kilometers north of Sept-Iles, Quebec.Over 2,800 employees work at the Carol Project to produce some 20.0 million tonnes of concentrate and 10.5 million tonnes of pellets annually.In 1979 our Training Department started to develop the DACUM System of training for our Concentrator Operations Department.DACUM is an individualized, self-learning, training program. It is both a curriculum plan and an evaluation instrument.To date, the DACUM System has been completed for all occupations in the concentrator and work will commence shortly to develop DACUM for our Pellet Plant and Mine Operations Departments."

Jan 1, 1982

By Unknown

More than 60 years ago Lakota (Sioux) Chief Henry Standing Bear asked Korczak Ziolkowski to create a monument of Crazy Horse in the sacred Black Hills. Today, you can see Standing Bear’s dream has grown into enormous reality. Crazy Horse Memorial, mankind’s largest mountain carving in progress, is being carved in the round and when completed will be 641 feet long and 563 feet high. Crazy Horse is only 17 miles from Mount Rushmore National Memorial, giving South Dakota unique boasting rights for having two extraordinary mountain carvings in such close proximity

Jan 1, 2009

By Gordon Revey

The challenge of managing blasting risk, types of risk, public perception, and a system for managing risk were covered in the first part of this article in the May/June 2000 issue of the Journal of Explosives Engineering. This final part of this two-part series provides a method for identifying specific blasting risks and reviews the importance of community relations.

Jan 1, 2001

By T. A. Kirk

"The Linatex Dewatering System is a compact, low capital and maintenance cost matched set of processing equipment suitable for solids recovery, dewatering and desliming sand-like materials in the range 3/8"" to 325 mesh ( 1). Since its introduction to North America in the early 1970s, various elements of the system have been successfully installed in a variety of applic11tions both in Canada and the U.S.A. Examples are chosen from the coal, fine aggregates, iron ore and industrial minerals industries.II. Elements of the Linatex Solids Recovery System(A) The Linatex Separator (See Fig.I)The Linatex Separator, which is the heart of the system, is a specialized type of hydrocyclone designed to give a self regulating rope discharge product. It has the familiar cyclone geometry of cylindrical and conical section, tangential inlet, apex and vortex finder. The apex is enclosed in a unique patented automatic underflow regulator consisting of a collapsible rubber sleeve, and the overflow line is a siphon-leg, with a controlled air bleed valve. The siphon leg is adjusted so as to balance the internal negative pressure acting as a closing force on the underflow regulator against the mass of slurry pressing down on it from the cone section of the Separator. With correct adjustment the underflow regulator will close drip-tight on a water only feed. As solids accumulate in the apex of the cone the weight of solids counterbalances the vacuum and cat1ses the underflow regulator to open and discharge classified material at a controlled density."

Jan 1, 1978

By Edgardo Orderique

Southern Perú Copper Corporation ha desarrollado un programa de reevaluación de las reservas para optimizar cada etapa del proceso y así llegar a las reservas mencionadas. En este sentido, el presente texto desarrolla el esquema de optimización de una secuencia anual de minado. El proyecto comprende la realización de de perforaciones en zonas llamadas geometalúrgicas, con el fin de realizar pruebas metalúrgicas y definir el comportamiento del mineral en la concentradora y lixiviación. También se incorpora el concepto de índice de solubilidad, parámetro que sirve para diferenciar adecuadamente un mineral económico para flotación del de lixiviación y finalmente, se optimiza la secuencia anual de minado y disposición de material en botadero. En consecuencia, es importante determinar el uso de software y hardware adecuado para planeamiento de minado, ya que depende de la magnitud de la mina como en el caso deCuajone.

Sep 13, 2001

By E. Lammer

"Underground mining processes are dangerous. The design of mining equipment, which is able to cope with the hostile underground environment, is a challenge for all machine manufacturers. Presupposition for realizing the vision of SANDVIK for zero harm for working with SANDVIK equipment is the installation of the appropriate processes. Into the product engineering and product development processes of Sandvik Mining and Construction, a specific "Product Safety Process" has been integrated, where all safety related activities like identification of all life cycle hazards, risk management and safety verification / validation are planned, performed and documented. Product safety shall be „designed into" the products. Therefore, specific research activities have been started, to address the safety and health related topics for the development and for the engineering of SANDVIK mining machines."

Jan 1, 2011

By Chulgi Suk, Hoon Park, Hyonsoo Kim, Hakman Kim, Sangho Cho

Dust emission from blast demolition and other construction activities can be a nuisance; it is widely recognized that fine particles less than 10 µm in equivalent diameter (called PM10) may cause health problems. Mist spray systems, such as rain guns, sprinklers, water/surfactant sprays (or foams) etc., are some of the most effective dust suppression methods. A large amount of research has showed that when water droplets are produced in an equal amount to that of dust particles, the airborne dust is suppressed by the agglomeration of dust and mist particles. A method for generating micro-sized mist from water, achieved by the detonation of explosives in the water tube, was suggested and is called the ‘detonationdriven water bag burst system’. There are many experimentally observed limitations of the explosioninduced water break-up process. The water bag explosion tests were simulated using the AUTODYN software, in order to investigate the aerosolization mechanisms of the detonation-driven water and water break-up process into micron-sized droplets. As a result of the numerical analyses, the diffusion direction of water when detonating in the central interior part of water tube was radioactive and significantly stronger than when detonating in the bottom exterior part; this is due to the compressive flow of the volume change inside of the water tube, which resulted from the blasting wave inside of the tube, as well as the reflected pressure on the ground. Blast tests of full-scaled reinforced concrete columns were conducted to verify the effectiveness of the suggested detonation-driven water bag burst system. The water breakdown and dispersion that occurred while blasting the reinforced concrete columns were observed using a high-speed camera, and dust generation was monitored using four density detectors. The suggested detonation-driven water bag burst system showed that the average dust density decreased by up to 7 mg/m3.

Jan 1, 2016

By Maral Papazian Bedian

Construction contracts in the USA contain the clause "Value Engineering" ? an interesting and curious clause allowing contractor initiated design changes. Misleading is the interpretation of value engineering implying cost saving and sharing with the owner, and curious is the timing, just before beginning of actual construction. It is not surprising that such a clause would simply be ignored, because it involves change, often major design changes in very short time; and change is feared, moreover, it is vehemently resisted by all parties, owner, designer, contractor. The problem in the USA may lie in the divergence and separation of the two entities: Designer/Engineer and Builder/Contractor, assigned to the "one" engineering project. The priorities and incentives of these two groups are very different. The Engineer spends years, even decades, in design and prepares contract drawings often without a deep understanding of construction methods. Worse, with all the time available to him and in our era of tremendous advances in computational methods and speed, the designer turns in plans that are inexcusably exaggerated code-based design with excessive safety factors. As to the Contractor, he builds, often without appreciation of design principles or regard for design engineers. Redesign to apply a new technology or optimization of an inferior design just before construction becomes unthinkable. It is not surprising that adverse and hostile relationship between the designer and the contractor is a norm with extended disputes and claims, not to mention the cost these entail. Surprisingly, "Value Engineering" was successfully implemented in record speed on several very large projects in the metropolitan New York area. The process of change was unconventional, painful, and even comical. Four case studies are presented: two Design/Build: the 1.2 billion dollars Hudson-Bergen Light Rail Transit System in New Jersey and the 90 million dollars MTA Bus Depot in Manhattan, and two Conventional Design/Bid/Build: the 90 million dollars Queens Boulevard Bridge and the 150 million dollars Long Island Expressway.

Jan 1, 2002

By Murray W. Hitzman

Two great revolutions in mining occurred during the 20th century. The first took place almost 100 years ago (1903-1905) with Daniel Jackling’s experiment in the economies of scale for large-scale mining at Bingham Canyon. Jackling’s ideas changed the focus of base metal exploration toward lower-grade, high-tonnage deposits. The second revolution was the impact of environmental and social concerns on mining. It started near the end of the 20th century and is still under way. This article speculates on the effects of this second revolution on the future of mineral exploration.

Jan 1, 2005

Standards And Laboratory Monitoring In Gold Assay Key Components Of Best Practice

Jan 1, 2005

1.1 The parties agree to submit all claims, disputes or controversies arising out of, or in relation to, the interpretation, application or enforcement of this agreement, including dispute resolution procedures, to sequential mandatory discussion, mediation and arbitration for resolution of all disputes before, and as a condition precedent, to self-help, arbitration, judicial action or other remedies. This mandatory procedure will resolve each dispute within one-hundred (100) calendar days. Any deadline falling on a federal holiday or weekend will be the next working day. Breach of this disputes process shall constitute a material breach of contract for which the aggrieved party may recover all costs, including attorneys fees, interest and other expenses necessary to resolve the dispute through litigation. The obligation to discuss and then mediate and arbitrate covers all disputes arising from every aspect of the Project to be built by the owner, including, but not limited to, design, engineering, bonding, indemnification, labor, material and services, and the acts or omissions of any related party for whom a party to this agreement may stand responsible.

Jan 1, 1994

By Frank van der Meer, Jorge Portocarrero, Alexandra Gruendken

"The number of High Pressure Grinding Rolls (“HPGRs”, also called Roller Press) installations instead of tertiary crushers is rapidly increasing. The technology has been largely accepted in the minerals industry and benefits, such as superior energy efficiency and a lower overall operating cost compared to alternative technologies, have been demonstrated at a number of operations throughout the world.This paper focuses on coarse hard ore operations and reviews the successful installation of the first Roller Press installed instead of a tertiary crusher at the Los Colorados Plant of CMH (Chile) in 1998. It details the experience obtained over the past ten years of operation from commissioning to the present day. It highlights examples of further developments made in the design to improve machine maintainability and availability as well as wear life of the grinding surfaces.A second focus lies on procedures to derive from small scale testing material properties such as wear life, flake formation and strength and their application to industrial size machines to optimize circuit design, especially when Roller Presses are used in closed circuit with screening.INTRODUCTIONRoller Presses (also known as HPGR, High Pressure Grinding Rolls) are considered today state of the art for the preparation of pellet feed. They are also gaining wide acceptance in coarse ore operations. One of the first successful operations in which a roller press was used to replace a conventional tertiary and quaternary crusher is the Los Colorados plant of CMH in Chile.When the Roller Press at Los Colorados was commissioned in 1988, there were 169 Humboldt Wedag roller presses in operation throughout the world. Of these, 14 were installed in the minerals industry. However, these were installed mainly for grinding pellet feed to increase the Blaine value. Up to that time, only three KHD roller presses had been applied for crushing coarse ore in specialized circuits. Moreover, the installation at Los Colorados was the first Roller Press ever to replace a conventional tertiary and quaternary crusher in a hard ore application."

Jan 1, 2009

By Shane Baker

Cementation Foundations Skanska Ltd encountered many significant challenges in designing and constructing the foundations for the LNG (Liquefied Natural Gas) tanks and associated structures at the Isle of Grain, Kent, UK. With LNG cargo ship levels fixed by the adjacent English Channel, the platform could not exceed critical thickness in order to achieve final grade level, so a safe and efficient working platform for construction equipment on extremely poor alluvial soils was designed and installed. The detailed pile design also required particular analysis of the pile group behaviour and considered seismic load cases not usually associated with UK pile design. Continuous flight auger (CFA) piles were the chosen foundation solution and design was verified through preliminary and working pile tests both axially and horizontally. Contaminated land and existing foundations from a previous oil terminal meant that removal of spoil was extremely costly so specific measures were taken to minimise the off-site disposal. The management of a package of general Civil Engineering in addition to the piling scope, coupled with an unrelenting production program has forced a raising of the bar for this foundation technique.

Jan 1, 2006

By Lisa Morrison

The 11th Annual Mineral Economics and Management Society (MEMS) conference was held April10-12, 2002, in Montreal, Quebec. It consisted of a series of technical sessions. Each paper addressed the economic issues that are related to the changes that many people believe are now required in the mining industry. Some of the papers were directed at how the mining industry will handle the changes that will be required in its philosophy and operations management. Of equal importance was whether the industry possesses the toolkit necessary to effect these changes and emerge stronger from its challenges.

Jan 1, 2002

By Steve Kral

More than 124,000 people involved in the mining and construction industries throughout the world poured into Las Vegas, NV in March for ConExpo-Con/Agg ’99. Show organizers said this triennial exhibition is the largest equipment show in the Western Hemisphere and one of the largest exhibition of any industry. “Clearly, Con-Expo-Con/Agg ’99 was one of the largest trade shows of any industry ever held in the Western Hemisphere,” said Bruno Benna, co-chair of the event. Attendees included mining industry representatives, including aggregates, and sand and gravel producers. In addition, many of the attendees work in the construction, reclamation, forestry, asphalt paving, landscaping and concrete industries. According to show records, about 52% of those attending were company presidents, vice presidents, chief financial officers or managers.

Jan 1, 1999

By H. J. McQueen

ORDER OF PRESENTATION ?INTRODUCTION TO THE VICTORIA BRIDGE ?REASONS FOR A BRIDGE AT MONTREAL ?RAILROAD BRIDGE REQUIREMENTS ?IRON PRODUCTION CANADA / WORLD AL ?METALLURGICAL INDUSTRY CANADA ?FAIRBAIRN, STEPHENSON SHIP PLATE-RIB BOX GIRDER ?VICTORIA BRIDGE (PREFABRICATED BRITAIN) ?IRON ORE SITUATION THE VICTORIA BRIDGE 1859, TUBULAR -WROUGHT IRON* 1898, TRUSS ?STEEL* (*HOT RIVETED) 1957, SPUR, LIFT SPANS ??DUCTILE WROUGHT IRON WITHSTANDS FATIGUE ?TO KEEP THE TRAINS ON TIME & ON TRACK? ??IMMOVABLE SHARP PIERS SPLIT ?THE IRRESISTIBLE ICE, STOPPED CITY FLOODS? ? ?********* ??111 YEARS-YOUNG STEEL TRUSS, (1898): ?STILL VITAL SEA-T0-SEA RAIL LINK? ? ?********* ??51 YEARS HAVE PASSED SINCE SEAWAY (1958) ?SWITCHED BRIDGE INTO DOUBLE LIFT SPANS?

May 1, 2011

By William M. Gleason

The war in Vietnam stretched into another decade, an American President was at the brink of impeachment, the earth was given its own day, twin tower monuments of American ingenuity were completed in New York and would stand high above the Manhattan skyline for 31 years. Inflation, oil shortages, low commodity prices and America’s 200th birthday were part of the decade — it was the 1970s. For the mining industry, the demands of the decade would be high and the challenges would be significant. Because of the many challenges that lined up in front of it, the mining industry was forced to work smarter and more efficiently. The industry also expanded its borders in search of new resources and struggled along with the rest of the world through a fuel crisis, inflation and a recession.

Jan 1, 2007

The value of raw nonfuel mineral materials production totaled an estimated $19.7 billion in 1978. The record 1978 value exceeded by 13 percent the 1977 value of $17.5 billion. This raw mineral output was the basis for approximately $200 billion worth of processed materials of mineral origin. Output of both metals and nonmetals increased about $1 billion each, above comparable figures for 1977. Of the 22 metals produced quantitative output of 11 increased and the value of 13 increased. Among the 48 nonmetallic commodities produced, the quantities for 35 increased, and the values for 40 increased.

Jan 1, 1979

By G. Swan, E. Nordlund, P. Zhang

"SynopsisThe most widely used support design damage criterion for rockburst-prone mines is based upon kinetic energy, which is proportional to the square of the ejection velocity and is commonly expressed in terms of peak particle velocity (PPV). Field monitoring and back-analyses have shown that ejection velocities of the order of 10 m/s and higher can result from seismic events of moderate magnitude. Such velocities are much higher than those predicted using PPV obtained from scaling laws. It has also been found that the peak ground motion (i.e. PPV) on the surface of an excavation is preferentially amplified (by four- to tenfold) compared to the motion in solid rock at a similar distance from the source. However, the wave propagation and interaction processes involved within the fractured rock in generating high ground motion are very complex and are not well understood at this time.In this paper, velocity amplification was investigated by modelling the dynamic interaction between fractured rock and a free surface using a 2D discontinuum-based numerical program, UDEC (Universal Distinct Element Code). A 1D model with a fractured zone was used to represent the fractured rock. Velocity amplification, quantified by PPV, predicted at the free end of the model was 2.0–3.6 times higher than the input velocity. It was found that the wave frequency, fracture stiffness, fracture spacing, and thickness of fractured zone are the main factors that affect the velocity amplification. The results have proved that the interaction of the seismic wave and multiple fractures near the free surface strongly influences the ground motion.IntroductionSince mining-induced seismicity is almost inevitable in deep mines, ground support is generally employed to mitigate the risk of seismically-induced damage. The most widely used support design criterion for seismicallyprone mines is one that seeks to maximize the absorption of the kinetic energy (plus potential energy if a gravity component is considered) of key rock blocks. Based on this criterion, design methods for rock support were first proposed by Wagner (1984) in South Africa and later improved, among others, by Roberts and Brummer (1988) and Kaiser et al. (1996)."

Jan 1, 2015

By Bengt H. Fellenius

Session 2, Deep Foundation without Soil Excavation, has attracted no fewer than 22 papers dealing with subjects from soil improvement by grouting, injection, and deep mixing techniques through vibroflotation and special piles, including aspects pertaining to conventional driven and bored piles. In the short time available, it is not possible to both do justice to the papers and provide a critical review of the state-of-the-art. Instead, to meet the objective of making the next half hour worthwhile to the audience, I have chosen to comment on a few special points brought forward in the papers and thereafter to discuss more in detail a couple of aspects I have deemed to be of general interest. Four papers deal with jet-grouting, injection, and deep mixing techniques: DOMSKI, J. J. Reinforcement of subsoil under the foundations of historical buildings in Cracow using deep injection technique. RESTELLI, A. B, BERTERO, M., and LODIGIANI, E. Deep mixing technology to improve the bearing capacity of a very soft clayey soil under an earth embankment.

Jan 1, 1994