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By John J. Stetler

Introduction Samarco Mineracao S.A. is a Brazilian corporation jointly owned by S.A. Mineracao da Trindade (SAMITRI) and Utah International Inc., with 51% and 49% interests respectively. Headquartered in Belo Horizonte in the state of Minas Gerais, Samarco owns and operates an open-pit mine capable of producing 10 Mt/a (11 million stpy) of iron ore; a concentrator rated at 7 Mt (7.7 million st); a 12-Mt (13.2-million st) capacity pipeline transportation system; a 7 Mt (7.7 million st) filtering and pelletizing plant; and a harbor facility. The mine, concentrator, and initial pipeline pump station are located at Germano, near the town of Mariana, about 300 km (186 mi) north of Rio de Janeiro by air. The pipeline terminal, pellet plant, and harbor are at Point Ubu, 70 km (43 mi) south of Vitória the capital city of Espirito Santo State, and about 300 km (186 mi) by air east of the mine. The 396-km (246-mi) pipeline uses 508-mm (20-in.) pipe except for a 53-km (33-mi) section where 457-mm (18-in.) pipe is used to absorb and control slack flow through increased velocity in one of the areas along the route. Iron Ore Slurry The hematite iron ore concentrate produced at the Germano plant is processed by grinding the average 53% run-of-mine itabirite iron ore to -150 µm (100 mesh) for gangue liberation. It is treated further by cyclones to remove the 10 µm (1250 mesh) slimes to prepare the ore for flotation. During the multistage cationic flotation operation, the silica is reduced to make low silica (-0.9%) concentrate for the direct reduction (DR) iron-making process or to make normal silica (-3.5% +2.5%) concentrate for the blast furnace (BF) iron-making process. The concentrate then is reground further to meet the particle size requirements for pelletizing. The reground hematite concentrate is screened in closed circuit with the regrind mills for close control of the maximum particle size, not to exceed 3.5% +75 µm (200 mesh) for pipeline wear protection. Thickened concentrates at 70% solids are pumped to four 5-kt (5,510-st)(dry) agitated slurry storage tanks that hold the feed before it goes to the first pipeline system pumping station. Pipeline Capacity The pipeline system was designed to transport 12 Mt/a (13.2 million stpy) at 65% solids with an average minimum safe operating velocity of 1.5 m/s (5 fps). The pipeline will transport 5 Mt (5.5 million st) in 1982. The system, therefore, is moving the slurry in 13-kt (14,330-st) batches, dispatched at intervals to move 20 kt/d (22,050 stpd). In operation, the pipeline has exceeded its 93% availability design factor. Pipeline Facilities Pump station No. 1 is located at the Germano minesite 1 km (3,330 ft) above sea level. It has the following principal equipment: • four 5 kt (5,510-st) (dry) agitate slurry storage tanks; • two centrifugal charge pumps (one stand-by); • a 217-m (712-ft) safety loop; • seven mainline positive displacement triplex plunger pumps (189 m3/h, or 832 gpm, at 14.9 MPa, or 2,162 psi, maximum output pressure); • four corrosion-erosion spools; • a control and command center. Operation The output at pump station No. 1, with 66% solids, is pumped 151

Jan 10, 1982

By F. Feichtinger, M. Riess, A. Lammer

Introduction This article discusses the unique range of properties of platinum and its applications as a high technology metal. World reserves of this strategic and precious metal are confined mostly to South Africa and, to a far lesser extent, the Soviet Union. An analysis is given of past trends in world platinum output. The timepath is computed for the world platinum output rate, covering a period of more than 350 years. This is based on the postulate that the industrial conversion of a virgin resource progresses according to a Sigmoid curve. This computation is performed by means of a nonlinear, three-stage optimization model employing a multiform Sigmoid function. Finally, the price dynamics are examined. Platinum is the most important of the group of the platinum metals to which it gives its name. Other platinum group metals are iridium, osmium, palladium, rhodium, and rhutenium. The metals occur in nature in close association and are chemically very similar to each other. Three members of the group - platinum, iridium, and osmium - are the heaviest metals known to man. Platinum's density is 11% heavier than gold and about twice the weight of the same volume of silver or lead. Properties Platinum is a typical grayish-white metal. Its special properties were known 1000 years ago to the American Indian craftsmen of what is now Ecuador and Colombia. From those distant beginnings, platinum is now firmly established as the most precious and distinctive metallic element known to mankind. It is shown in Table 1, platinum has a unique wide range of physical, chemical, and mechanical properties including high melting point, resistance to chemical attack, high catalytic activity, mechanical strength, and malleability. These properties make it indispensable for use in many industries. Application Platinum is first and foremost a high technology metal. During the last few decades, fertile scientific minds searched for and developed widespread cost-effective uses for this precious metal. Its unique properties render it irreplaceable in many key industrial processes. Important major fields of application include: • protection of man's natural environment (pollution control), • defense, • fuel production, • fertilizer manufacture, • glass and glass fiber manufacture, • pollution-free energy generation - replacement of nuclear and fuel operated power plants, • electronics, • dentistry, • medicine, and • jewelry. Besides these industrial markets, platinum is increasingly finding a place in investment portfolios around the world as investors switch from gold and silver holdings to this relatively scarce and strategic commodity. Platinum has a growing popularity among private investors. This is being accelerated by the predicted "big crash" of the US dollar and its associated weak currencies, which American financial analysts are expecting towards the end of the decade. Figure 1 shows the demand for platinum in various applications throughout the western world in 1986. The total demand amounted to 88.6 t (97.6 st) of which autocatalyst usage accounted for 32.8 t (36 st) or 37%, the biggest share. Catalytic converter technology is increasingly centered on rhodium-platinum three-way catalysts. These catalysts are able to deal with all three pollutants - carbon monoxide, hydrocarbons, and nitrogen oxides - in a single catalytic unit. The introduction of these three-way converters will result in a further steep rise in the platinum demand for autocatalysts. Among all the metals used in the antipollution devices for automobiles, platinum remains

Jan 2, 1988

By Takeshi Tanaka, Yasuhiro Komamura, Yuusaku Tominaga, Takayoshi Iwamoto

In order to assist better countermeasures for ventilation control in normal/abnormal condition of mine ventilation network in real time, branch relation table derived from a macroscopic characteristic of ventilation network is introduced in this study. The main results in this study are as follows; 1) One of macro characteristics of a ventilation network, as a relation between airflow rates in two branches chosen arbitrarily, is specified under the change of aerodynamic resistances in a branch. Airflow rate in a branch can be estimated by airflow rate in other branch changing aerodynamic resistance by using empirical formula. The empirical formula by computer simulation of the Horonai coal mine, Japan is considered to be a one-valued function with monotone or extremums. 2) A branch relation table shows the macro characteristics, mentioned above, of all the set of two-branch combinations in a network. Elements in the table give both information of control possibility range of airflow rate and total number of extremums in an empirical formula. 3) It is important that when aerodynamic resistance change in a branch is estimated by measuring airflow rates in two typical branches, the two branches should be chosen from branch combinations with monotonous relation in the branch relation table. 4) A flexible expert system to assist ventilation control in the specified branch in real time has been developed by using a branch relation table for a ventilation transfer diagram of the specified branch, such a coal face and an advancing face. A fuzzy reasoning is utilized in the recognition of the safety factor, methane concentration, in the system. And when conviction degree in recognition for methane concentration at the specified branch is too low, the system searches for other branch combinations in the branch relation table stored in the system, to use other ventilation transfer diagram of the specified branch. When a needed ventilation transfer diagram is not stored in the system, the expert system asks automatically the ventilation simulation from other computers linked to the main computer automatically. The system repeats consultation until conviction value of safety in the specified branch approached

Jan 1, 1993

By James Matlock

The announcement of a minable reserve of 13.6 Mt (16 million tons) averaging 0.9 g/t (0.027 oz per ton) Au and 2.4 g/t (0.71 oz per ton) Ag for the open pit-heap leach reserve at Red Mountain No. 3 in Ouray County, Colorado, by Cornucopia Resources in November 1985 brings another open pit-heap leach precious metal ore body to the production stage. With about 8.2 Mt (9 million tons) of waste and metallurgical studies showing acceptable recovery rates, low reagent consumption, and good final percentage recovery, Red Mountain is a discovery that will add to the precious metal inventory of the US. Frank Baumgaruler of Denver, CO, recognized the precious metal potential in Red Mountain No. 3 and acquired all of the old claims. James Matlock conducted a field reconnaissance over Red Mountain No. 3 independently of the Baumgartner activities and recognized epithermal alteration and mineralization in the Tertiary volcanics. He recommended acquisition of the ground and was able to obtain rights and drill six core holes for Amoco in 1982. Amoco drilled a further nine core holes in 1983, but then dropped the property. Cyrano Resources examined the data and through its consulting geologist, V.F. Hollister, acquired the rights dropped by Amoco. In 1984 Cyrano began further drilling of the ore zone demonstrated by Amoco but they were then acquired by Cornucopia Resources. Cornucopia completed development of the property and commenced the permitting process in 1986. The property was recognized as a disseminated gold deposit by both Baumgartner and Matlock, and both deserve credit for properly evaluating mineralized outcrop in the Tertiary volcanics. However, Cornucopia recognized the profit potential in the heap leach exploitation of the ores and de- serves credit for completion of premine feasibility studies. The discovery is clearly a geological one, but the premine engineering studies were essential to the conversion of the prospect to a commercial mining enterprise. The deposit lies on the circular bounding fault of the Silverton caldera. Two reprints follow that help understand the geologic setting of the ore controls.

Jan 1, 1990

By William Paul Robinson

I would like to first summarize the relevant health information relating to the workers and general populations around uranium mining as a basis for understanding the hazards associated with these operations and their available remedies. This discussion will summarize the literature on Radon and its daughters, among the most toxic uranium decay products. Second, I will discuss waste handling in the uranium industry: past, present and future, discussing exploration, mining, and milling and the volumes of water and solid and gaseous wastes which are associated with these various phases of uranium operations. This paper will also include a discussion of the various past and present materials handling technologies and their responsiveness to the concern for uranium waste isolation. I will then conclude with a summary of recent modifications in the relevant standards as applied to uranium mining and milling. Joseph Wagoner, a research epidemiologist with the U.S. Public Health Service has summarized the literature on uranium mining and its health effects in his written testimony as a commissioned witness in British Columbia Royal Commission of Inquiry into Uranium Mining in January of 1980, entitled Uranium, The U.S. Experience: A Lesson in History.1 Briefly summarizinq his report, as early as 1546, miners of uranium bearing ores in Central Europe were reported to have unusually hiqh frequencies of fatal lung disease2. As early as 1879, the real nature of pulmonary disorders among these miners was first diagnosed to be malignant neoplasia or lung cancers. Of 655 miners dying between 1875 and 1912, 40% or 276 of these Central Europe miners died of lung cancer.4 By 1939, it was reported that lung cancer mortality rate for miners in these Central European mining districts was several times (9.7 per 1000) higher than that for similar populations in Vienna, Austria (0.34 per 1000). Thus, before uranium mining began in the U.S., there was a considerable body of information linking uranium mining to lung cancers. The U.S. experience can be summarized in Table 1 also from Wagoner's B.C. Testimony.1 This table shows that through 1978, 205 respiratory cancer deaths have been observed among white underground uranium miners in the

Jan 1, 1980

By Jeffery L. Kohler

The research and development of a pattern recognition system which can predict incipient failures and safety hazards in the mine power network is described. An examination of mine electrical safety hazards revealed they are often related to the electrical equipment down-time experienced on mine sections. Based on this, a method is proposed that can improve both production and safety, without compromising either. Equipment failure modes are examined to illustrate how the ultimate failure can be predicted for enough in advance to allow a convenient and safe repair, followed by a discussion of actual monitoring system performance. Finally, the paper is concluded by projections of the system's utility to industry.

Jan 1, 1977

By Edie Trimmer

Utah statute defines sovereign lands as "those lands lying below the ordinary high water mark of navigable bodies of water at the date of statehood, and owned by the state by virtue of its sovereignty." The lands within the bed of Great Salt Lake (GSL) are, by this definition, sovereign lands, acquired at statehood in 1896 in accordance with the "equal footing" doctrine, granting each state control and ownership of navigable waters and the lands underneath those waters within its borders. Under public trust doctrine, the state, as trustee for the people, bears responsibility for preserving and protecting the right of the public to use of the waters for navigation, commerce, fishing, recreation, and wildlife habitat. Also by statute, sovereign lands are defined as "state lands," to be managed by "multiple use sustained-yield principles." The Division of Forestry, Fire and State Lands is given management authority for sovereign lands and, as manager, has responsibility to prepare comprehensive plans, initiate studies of the lake and its resources, implement comprehensive plans through state and local entities, and coordinate the activities of various divisions within the Department of Natural Resources (DNR). The Division of Forestry, Fire and State Lands also has responsibility for management of mineral leasing on sovereign lands. The many resources on the lake--water, minerals, wildlife, recreation, archeological and historical values--are managed by as many state agencies which occasionally creates conflicts. The brines of GSL contain several ions that crystalize into valuable minerals during evaporation. The major ions in the lake are, in order of relative abundance, chloride, sodium, sulfate, magnesium, and potassium. Mineral products which are currently extracted from lake brines are sodium chloride, magnesium chloride brine which can be sold as flake magnesium chloride or further processed into magnesium and chlorine gas, and potassium sulfate. Mineral products which have potential for extraction include gypsum, sodium sulfate, and trace amounts of lithium, boron, and bromine. The GSL contained an estimated 4.3 billion short tons (st) (3.9 billion metric tons [mt]) of dissolved salts in 1998. Utah Geological Survey (UGS) estimates of the dissolved salt content in GSL have fluctuated from 4.0 to 5.5 billion st (3.6 to 5.0 billion mt) due to the dynamic conditions in the lake as salts are precipitated and redissolved, and due to the diversion of brines from GSL, such as the West Desert Pumping Project. The lake has four areas of varying salinity, separated by dikes or other man-made structures: north arm and Stansbury Bay brines at near saturation (25 to 27 percent total dissolved solids [TDS]); the main body of the south arm with concentrations ranging from 7 to 15 percent TDS as lake elevations fluctuate; the waters in Farmington Bay at approximately 3 to 5 percent TDS; and Bear River Bay at <1 to 7 percent TDS. The percent TDS in Bear River Bay fluctuates with lake level, and changes in Bear River inflow. The transfer of salts from the south arm to the north arm has raised questions about the viability of the mineral and brine shrimp industries. The UGS and the U.S. Geological Survey (USGS) continue to monitor salinities at designated sites on the lake to document changing lake salinity. A recurrent theme is that placement of dikes and diversions can have significant and rapid impacts on various conditions in the lake. Hydrocarbon resources on the lake are significant, but presently undeveloped. The hydrocarbons are low gravity (4 to 9 degree API) and tar-like, contain high nitrogen concentrations, and up to 12 percent sulfur. The unusual characteristics of the oil have been the subject of studies by chemists at Weber State University and University Louis Pasteur de Strasbourg. However, these resources are difficult, and at present, uneconomic to extract using current technology because of the nature of the hydrocarbons, and production in "an offshore, highly saline environment." Oolitic sand deposits make up many of the beaches and shorelines around the lake. Because of their high calcium carbonate content, oolites have been used by Magnesium Corporation of America (MagCorp) and its predecessors for acid neutralization and dike construction. Oolites are also used in very minor amounts in flower drying. The Utah Division of Oil, Gas and Mining reports up to 130,000 st (118,000 mt) mined annually by MagCorp from U.S. Bureau of Land Management (BLM) lands adjacent to GSL. Currently, there are twelve producing mineral leases which generated slightly more than $1,000,000 in royalties during calendar year 1998. IMC Kalium Ogden Corp. (IMC Kalium) produces potassium sulfate and magnesium chloride from brines concentrated through solar evaporation in Bear River Bay and Clyman Bay. By-product sodium chloride is transferred to IMC Salt, which packages and sells the salt. MagCorp produces magnesium metal from brines concentrated in Stansbury Bay. Cargill Salt produces sodium chloride from brines provided by MagCorp under a lease agreement. Morton Salt produces salt at the southeast end of Stansbury Island. Lastly, North Shore Limited produces cocentrated brines for use in dietary and mineral/vitamin supplements near Spring Bay in the north arm of the lake. Producers of magnesium, potash, and salt from GSL contribute significantly to the value of metals and industrial minerals in Utah. Together these companies contribute approximately $240 million in gross value, or 18 percent of the value of the state&apos;s nonfuel mineral production. Most of this production is exported.

Jan 1, 2001

By Michal Bukovansky

The Sahara Desert presents a serious obstacle to transportation route development in northwest Africa. Most highways and railroads are now limited to the coastal regions. A network of pioneer roads is the only connection between Algeria, Morocco, and Tunisia on the north, with Mali and Niger on the south. A feasibility study has recently been made for a paved highway between these countries. Climatic, geologic, physiographic and hydrologic conditions will significantly influence the construction of the road. In order to reduce costs, special construction methods will be required. An outline of these I conditions and methods is presented as an example of an engineering geological investigation in desert conditions.

Jan 1, 1970

By H. B. Oblad

The WEMCO® SmartCell™ flotation machine is a continuously-stirred tank reactor in which solids are suspended in water and are contacted with air. The reaction is particle flotation resulting in the separation of valuable material from gangue. The effects of several operating variables on the flows of water and air and on motor power were measured. A miniature magnetic flowmeter was installed in the draft tube that allowed measurement of the water flows into the rotor. This work has led to a better understanding of machine function which will lead to improved performance and better operation. General equations for optimization, design, and scale-up were inferred.

Jan 1, 2002

By Fred H. Lightner

Mergers and acquisitions (M&A) within the mining industry are becoming frequent events. Large companies and small companies alike are jumping on the bandwagon of merger mania. The results of these mergers have significant impacts on the employees of the involved companies. Comments, observations, and specific examples of the &apos;peop1e"aspect of mergers are presented in an attempt to answer the question "will it be business as usual?" My answer is a simple NO. This paper attempts to provide support for my conclusion. The reader should recognize that the comments, observations, and specific examples mentioned in this paper are subjective and reflect the experience and prejudice of the author.

Jan 1, 2001

By J. C. Cawley, J. Sottile, J. L. Kohler

Control circuit failures contribute significantly to continuous miner downtime. The time required to put the machine back into production is a function of the time required to diagnose the problem, obtain parts and make the repair. Of these, the diagnostic time is often the largest. A microprocessor-based system with the ability to diagnose all of the common control circuit failures was designed, installed on a continuous miner and tested. This paper summarizes the development of the diagnostic system and provides examples of the system&apos;s diagnostic capabilities. Implementation issues and the hardware used for the prototype are briefly described. Comments on the system&apos;s performance are also presented.

Jan 1, 1995

By D. E. Ranta, Leigh A. Readdy

Defining classes of ore using geostatistical methods that match historical classifications has presented problems in the past. A simplistic and practical approach to this problem is presented. An example of the approach is presented using a porphyry-type system as a case study. The technique described uses area of drill-hole influence and known conditions from similar deposits, or the production history of the deposit being studied. It provides a practical bridging mechanism for defining the class of ore on a block-by-block basis using the error of estimation value developed during kriging. The approach provides a filtering method that refocuses attention on the adequacy of drill-hole spacing.

Jan 1, 1992

By James A. Barclay

Results of investigations over approximately the last 10 years by the Bureau of Mines and others on technology for recovering cell-grade alumina from domestic nonbauxitic resources such as clay, anorthosite, alunite, dawsonitic oil shale, coal ash, and coal shale are reviewed. It is concluded that, although many innovative techniques have evolved from this effort and have been shown to be technically feasible, energy and economic considerations will prevent any of the processes from competing with the Bayer process under normal conditions. Based on the Bureau&apos;s experience, some variation of clay-HCI leaching, HC1 gas sparging crystallization has the greatest potential as an alternative to the Bayer-bauxite process.

Jan 1, 1984

By Lee F. Robinson, Angus W. Morrison, Norman M. Anderson

About 100 years ago the acid and chlorine oxidation routes for gold extraction were abandoned in favour of cyanide/ oxidation processes. Now a return to acid processing is in progress. One publication in particular led HM C Technology to investigate the reaction of dilute nitric acid and alkaline metal chlorides with refractory gold ores.(l) The one stage system of gold and silver recovery from sulphidic ores is described below. It is rapid and does not use large or expensive plant or special pressure equipment. It eliminates calcining followed by cyanidisation and shows a simple way of recovering the gold directly. Patents have been granted in some countries (2).

Jan 1, 1990

By A. E. Koski

This paper describes the implementation of specialized software in mine planning at the Cleveland-Cliffs’ managed Empire Mine on Michigan’s Marquette Iron Range. The application puts together years of mining experience on the eastern end of the Marquette Range beginning in the early 1960’s. The Empire Mine, in its thirty-fifth year of production, uses the software to model a complex and highly variable low grade magnetite orebody, capturing the economics of mining and processing to the final product. With special attention given to geostatistical methods, the software is used for all geologic modeling, ore reserve estimation, ore control, pit design and short and long range planning.

Jan 1, 1999

By James A. Pappas, Francis L. Fong, Tracy K. Lundin

The impact of environmental regulations on the quality of tunnel groundwater discharges is examined in this paper. Tunnel contractors usually depend on specialty contractors or outside consultants to deal with this issue without carefully examining their activities to minimize the production of contaminants. This approach may not be adequate given increasingly more restrictive environmental requirements. This paper surveys the general practice of the tunneling industry and attempts to identify sources of contaminants which may affect the total suspended solids, oil and grease content, and pH of the discharges. Strategies for treating the discharges are included. Field data and observations from several tunneling projects are also presented.

Jan 1, 1995

By Ronald L. Wiegel

The United States produces approximately 40 mil- lion tons of phosphate rock per year. Most of this rock is converted to diammonium phosphate and used as a fertilizer component for the domestic and international agricultural market. Much of this phosphate rock production is concentrated in the southeastern United States, with about half coming from washing and screening operations and half from flotation separation from sand and clay. This paper summarizes current operating practice in the industry and touches on some of the emerging technologies required to solve the problems associated with a diminishing high- grade reserve and the need to implement dolomite/francolite separations on a commercial scale.

Jan 1, 1999

By P. K. Kaiser

A rational approach for the design of fully grouted bolts in underground excavations is presented. An analytical model involving elasto-plastic concepts and the mechanics of bolt/ground interaction was developed and tested by comparison with laboratory tests and field measurements. The theory elucidates the influence of shear stress distribution, bolt pattern and geometry on tunnel convergence. Laboratory simulation has provided convincing evidence to support the theoretical predictions. A dimensionless bolt efficiency parameter is introduced as a design tool that relates the reduction of tunnel convergence to the bolt length and density. Its application in practice is highlighted by the analysis of one case history.

Jan 1, 1987

By Akira Usui

Ferromanganese crusts on topographic highs in the western Pacific Ocean are believed to be potential resources of cobalt, nickel and platinum. Earlier shipboard geological and geophysical studies by Japanese organizations have focused on mapping of distribution of thickness and metal contents of the deposits when estimating the total reserves. This paper summarizes our attempt to obtain more feasible data of distribution patterns and configuration of the deposits which are important parameters for resource evaluation at some seamounts in the South Pacific Ocean. Morphology of the seamounts and micro-topography of the sea floors are described using shipboard acoustic remote sensing, deep-tow sonar images, and TV/camera. [ ]

Jan 1, 2008

By David R. Zuchelli, Elio L. . Checca

Two case studies of methane gas explosions and their effect on the operation of underground coal mines are presented. The studies detail the recovery operations and investigations at each mine site. These include the circumstances prior to the explosions and the effects on the surface and underground ventilation control systems. Various ignition sources such as surface and underground electrical power systems, degasification sites, ventilation shafts, test well casings, and lightning activity were investigated. In each case, a lightning report from the National Lightning Detection Network1 was used in conjunction with the physical evidence and eyewitness accounts to confirm lightning strikes as the ignition source for the explosions.

Jan 1, 1995