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By David A. Greenhut

The Kubota surface melting system has been under development since 1975. It has found commercial application on the melting of municipal sludge, and ash from solid waste. The melted product has physical properties allowing its use as a substitute for aggregate in cement and asphaltic construction. This paper describes the surface melting system, its current use and anticipated future use.

Jan 1, 1991

By J Jones

A common problem in the mining industry is that company exploration groups operate in relative isolation to the rest of the company; resulting in poor knowledge transfer (Qureshi and Briggs, 2006) and often priority conflicts with mine geology, operations and project departments. In recognition of this problem, Newcrest created a Minerals Division responsible for stewardship and governance of mineral assets across the value chain from reconnaissance to rehabilitation. It was recognised at an early stage that effective collaboration both internally and externally would be required to improve decision making, deliver faster cycle times and improve governance.Collaboration in companies is generally associated with the introduction of new IT functions. However, modern IT-based collaboration systems and practices are relatively simplistic compared to the long-standing practices associated with collaboration and knowledge management in science and engineering disciplines such as geology and mining.The authors of this paper have started a trial of a 12-point plan for effective collaboration, which recognises that significant efficiencies can be gained and barriers to future success removed if more effective collaboration can be achieved between science and engineering divisions in a company along with external professionals and with the collective intelligence (Tapscott and Williams, 2006) of the outside world. To meet growth aspirations some companies, like Newcrest Mining Ltd, are adopting this comprehensive, step change approach by moving from a closed model the isolates mine geologists to an open and collaborative model that uses IT visualisation systems strategically. The paper describes how an open model provides people with the right work environment and the right information at the right time, which will help individuals and workgroups to work more collaboratively day-to-day. The aim is to achieve speed, focus and mitigate risk through an environment where everyone and anyone can contribute effectively (Cisco, 2008).

Aug 22, 2011

By W. R. Lindsay

Anyox, where the Hidden Creek mine of the Granby Consolidated Mining, Smelting and Power Company is located, is situated on an excellent deep-water harbour in Granby bay, at the head of Observatory inlet, about 600 miles from Vancouver and 90 miles north of Prince Rupert. Anyox is the Indian name for the little stream which empties into Granby bay, and means 'hidden creek'. The Ore-Bodies The ore is a replacement deposit and occurs at and near the contact between argillites and a later intrusive greenstone. This contact locally has a general north-and-south trend, an irregular westerly dip, and in the vicinity of the ore-bodies there has been intense folding, accompanied by faulting. The mineralizing solutions supposedly were derived from the Coast Range granite batholith, distant one to two miles to the east and north. The whole area is cut by many dykes of varying widths, which seem to have had but little part in the ore deposition.

Jan 1, 1929

By J. L. Bowlby

Introduction In the following discussion, boiler-feed and mine waters will be considered from the point of view of the problems arising from the chemical nature of the mineral and gaseous impurities they contain. The theories underlying some of these problems will be reviewed for the purpose of getting a clearer concept of the problems themselves. Certain terms of a chemical nature, necessary to the discussion, will be explained on the assumption that they are not generally familiar to mining engineers. Finally, an attempt will be made to correlate theory and practice, with the abject of establishing certain limits to factors relevant to the problems, and to show that these limits are justified by practical experience. The general problems occasioned by the presence of mineral and gaseous impurities in boiler-feed and mine waters are: (1) Scale formation and corrosion in boiler systems. (2) Corrosion of mine pumps and pump fittings. These will be discussed separately. Boiler Scale Typical analyses of waters available for use in steam power-plants are given in the accompanying Table (Table I). All analytical data are expressed in grains per Imperial gallon. The bicarbonates of calcium and magnesium in the raw waters are shown as normal carbonates in the Table. Substances in the first five rows constitute the encrusting solids. All the waters listed in Table I would be classified as 'very good' in the schedule of classification for boiler waters adopted by the American Association of Railway Chemists in 1887. In spite of this classification, however, the waters contain sufficient encrusting solids to cause serious scale trouble after prolonged evaporation.

Jan 1, 1934

By David Yankovich, Geoff Hughes, David Haug, Jon Kaneshiro

"In March 2013, the Sanitation Districts of Los Angeles County began final design of the Joint Water Pollution Control Plant (JWPCP) Effluent Outfall Tunnel project. The new, approximately 7-mile, 18-ft internal diameter tunnel will provide additional capacity and redundancy for the existing 8- and 12-foot diameter tunnels, which were built in 1937 and 1958, respectively. Connections to an existing, active 14-foot arch force main and four existing ocean outfalls ranging from 5- to 10-foot diameter are required. This paper will present geological features for the project, and details of the proposed post-tensioned tunnel liner and associated structures. INTRODUCTION The Sanitation Districts of Los Angeles County (Sanitation Districts) are 23 independent special districts serving approximately 5.3 million residents in Los Angeles County. Seventeen of the districts that furnish sewerage services to the metropolitan Los Angeles area are signatory to a Joint Outfall Agreement that provides for a regional, interconnected system of facilities known as the Joint Outfall System (JOS). The JOS service area is shown in Figure 1. The JOS serves an area that encompasses 73 cities as well as unincorporated territory and parts of the City of Los Angeles. The JOS provides wastewater collection, treatment, reuse, and disposal for residential, commercial, and industrial users, and it includes seven treatment plants, the largest of which is the JWPCP, located in the City of Carson. Currently, secondary treated effluent is conveyed through two 6-mile long parallel tunnels, 8- and 12-feet in diameter, from the JWPCP to a manifold structure located at Royal Palms Beach, near White Point on the Palos Verdes (PV) Peninsula, from which four seafloor outfalls extend offshore. The two main outfalls, 90- and 120-inches in diameter, extend approximately 1.5 miles offshore and discharge at a depth of approximately 200 feet below sea level. The other two outfalls, 60- and 72-inches in diameter, are used for additional capacity during heavy rain events and extend a shorter distance offshore and discharge at shallower depths. A schematic of the existing system with the proposed tunnel and structures is shown in Figure 2, and the proposed 18-ft diameter tunnel alignment is shown in Figure 3. Both existing tunnels and main outfalls are required to be in service at all times."

Jan 1, 2016

By C. R. Nisewanger, F. W. Brown

"The velocity of detonation of an explosive is one of its most important properties, because its performance depends markedly on the rate at which it releases its energy. Fortunately, the velocity of detonation is one of the few properties of an explosive that can be measured precisely. However, the velocity of detonation of an explosive may depend on several factors other than its chemical composition, such as density, physical state, degree of confinement, nature of confinement, and magnitude of initiating impulse. Presumably for an explosive of fixed chemical and physical properties there are certain limiting conditions of confinement and initiation under which the explosive will detonate at a maximum constant and uniform velocity. This velocity is its ""ideal"" velocity of detonation. It is obvious, however, that in order to evaluate performance properties of an explosive in all of its applications it may be necessary to measure its velocity of detonation under a number of conditions in which the velocity of detonation is far from the maximum ""ideal"" velocity.. Under certain-conditions the velocity of detonation may even,be,different at different points in the explosive.It is .relatively simple to determine the velocity of detonation of an explosive under a. standard set of conditions if one is free to use large quantities of the explosive and to form it into a convenient shape. Under these circumstances; one can use a thin column of explosive a meter or more in length. The time required for an explosion to travel the length of the column will not be less,of the order a few ten-thousandths of a second and can be readily and accurately measured .by means of the standard spark chronograph or by photographing the explosion with a rotating-drum camera. However in many applications the explosive charge may be of relatively small dimensions arid may not be in a form convenient for making velocity measurements and often may be enclosed in a case or other confining medium. It may be necessary to determine the velocity of detonation over distances of the order of a few centimeters, in which case the time intervals to be measured will be extremely small. For example, the time required for an explosion to traverse 1 centimeter of tetryl is of the order of 1.5 microseconds.Since no satisfactory method of determining time intervals of the order of magnitude of a few microseconds within an explosive charge was available,, at least not for all conditions that might be encountered in practice, it was necessary to develop a special electronic chronoscope which is capable of measuring time intervals as small as a microsecond with a fair degree of accuracy. This report describes the chronoscope and its application to measurements of velocities of detonation in explosives."

Mar 1, 1946

By Michael T. G. Brown

Syncrude Canada Ltd. has recently completed construction of its ambitious tar-sand mining and processing facilities at Mildred Lake, Alberta. The Syncrude site is approximately 48 km (30 miles) north of Fort McMurray near the west shore of the Athabasca River. The Syncrude operation involves the open-pit mining of approximately 270,000 tonnes (300,000 tons) of tar sand daily using draglines and a conveyor system. Bitumen is extracted from the tar sand, upgraded to oil-gas and transported to refineries in Edmonton and other locations for final processing . The Beaver Creek Dam forms part of the mining facilities for the Syncrude tar-sand mining operation. Water from Beaver Creek is diverted from the open-pit mine site south to the Athabasca River via Ruth Lake and the Poplar Creek Dam. General site layout is shown on Figure I . Design of the dam was completed by R. M. Hardy and Associates Ltd. of Edmonton, Alberta (now Hardy Associates (1978) Ltd) . Construction was undertaken during the summers of 1974 and 1975 under the direction of Canadian Bechtel Limited, managing contractors for Syncrude Canada Ltd. Total length of the dam is approximately 2.8 km (1.7 miles), with a maximum height in the order of 16 m (50 ft) The Beaver Creek Dam is located in a broad, flat, poorly drained valley. About 50 per cent of the site is covered with treeless peat deposits, which ranged in thickness from in excess of 5 m (15 ft) at the east end of the dam to less than 1 m (3 ft) at the central portion. The peat deposits overlie Pleistocene meltwater sediments on top of clay/clay shales of the Clearwater Formation and the tar sands of the McMurray Formation. The peat deposits and high groundwater levels at the site combine to make the excavation and construction of a conventional rolled clay cutoff impractical. For these reasons, the slurry cutoff trench technique was utilized to produce an efficient and effective seepage cutoff under various sections of the Beaver Creek Dam .

Jan 1, 1979

By Oliver Bowles

A NORTH CAROLINA miner dreamed that he found high-grade mica by excavating a certain corner of his mine. The next day he sank a hole on the exact spot and found mica of excellent quality. The dream came true. May not this be as good a method as any yet known for forecasting the valuable mineral content of pegmatites? The Federal Geological Survey has found in its recent detailed studies in New England that good sheet mica occurs most abundantly in zoned pegmatites, particularly in zones lying along the wall or contact of the pegmatite mass. Although this conclusion may be a valuable guide, pegmatite mining operations must still be classed as most uncertain and hazardous enterprises. Finding of the second largest diamond ever discovered in the United States-a stone of good gem quality weighing more than 34 carats-during the course of a horseshoe pitching contest at Peterstown, W. Va., is another example of unorthodox mining methods. These should not be considered, however, as characteristic mining methods developed in 1944.

Jan 1, 1945

By William W. Adams

Progress made by the quarrying and related industries of the United States during 1939 included increases in the number of men employed and the number of man-hours worked and reductions in the death and injury rates per million man-hours of exposure to risk. Forty-seven States reported quarries in operation; in each of 26 States the industry employed 1,000 or more men. Of these 26 States, 16 reported lower accident rates than in 1938. Among the operations of various types for which separate figures are published in this bulletin, the limestone, lime, and cement groups reported lower accident rates. During 1939, 79,449 men were employed in the quarrying industries. The period of operation of the plants averaged 236 clays per employee, with a total working time that equaled nearly 144 million man-hours. Accidents at the plants resulted in 48 deaths and 5,204 disabling injuries among the workers. Expressed as frequency rates, the accidents represented 0.33 fatality and 36.18 injuries for each million man-hours of work performed during the year. The major cause of fatal accidents inside the quarries was falls or slides of rock or overburden; nine deaths were reported from this cause. Four men were killed by explosives and four by falls of persons. Nonfatal injuries inside the quarries were clue chiefly to handling materials; about one-sixth of the total number at all operations in connection with quarries and related plants were in this class. Flying objects also caused numerous injuries, although only about one-half as many as did handling materials. Next in numerical importance were injuries from falls of persons. Then followed accidents caused by falls or slides of rock or overburden and accidents caused by machinery.

Jan 1, 1941

By Mark J. Zdunczyk

"Frac sand is industrial silica sand much like glass, foundry, filtration and blast sand. The sand must meet certain specifications set forth by the industry that consumes the product. The production and consumption of frac sand has experienced record growth in the last 10 years because of new oil and gas drilling, new horizontal well drilling, multi-stage fracturing and the stimulation of older wells that have little or no production. Frac sand is needed to “prop open” the fractures in the rock reservoirs to allow oil and gas to flow out more freely.According to the U.S. Geological Survey (USGS), the estimated production of frac sand in 2015 was 71 percent of the total production of industrial silica sand or 67.4 Mt (74.3 million st). This is a decrease of about 12 percent from 2014. However, the silica sand industry and other industry sources estimate only 50 Mt (55 million st) of frac sand were produced in 2015. In recent years both the USGS and industry studies have been very close in estimating the production of frac sand but with the recent downturn in frac sand production, perhaps, reporting to the USGS was not as accurate. These discrepancies may be that the USGS statistics are based on voluntary reporting by the industry and some companies report their approximate production, others may not. It is always difficult to obtain accurate production figures of any industrial mineral or construction aggregate operation as most companies tend to keep those figures somewhat confidential. It is certainly accurate to report that the production of frac sand had decreased since the last quarter of 2014 and through 2015. The oversupply of oil and natural gas has led to this decline in frac sand usage. Oversupply has idled drilling rigs and well completion activities. World Oil Magazine reports that 2015 was the worst year for rigs in a quarter century. The only wells being completed are those that have contract agreements to do so, others have been capped. Very few new wells are being drilled. Since about 98 percent of well completion is sand and water, the sand supply has caught up with the demand. There are some bright spots in the “oil patch” as the Permian Basin in Texas and the Woodford Shale in Oklahoma have kept pace somewhat with drilling and completion. It has been reported that the frac sand producers in the Brady-Voca, TX area are producing to nearly capacity. The northern frac sand producers like those in Wisconsin, Illinois and Minnesota are feeling the downturn because of the cost of shipping sand to these moderately active basins and plays. The “rule of thumb” is that freight is 2/3 and sand is 1/3 the cost."

Jul 1, 2016

By Jeff Hopple

"Bluestone Dam in Hinton, W.Va., along the New River, is owned and operated by the U.S. Army Corps of Engineers (USACE). Completed in 1949, the dam is 165 ft (50 m) tall, 2,048 ft (624 m) wide, and encompasses a water shed that is 4,600 sq mi (11,914 sq km). The Bluestone Dam Safety Assurance (DSA) Program began in 2001, and is a multiple-phase construction project to upgrade the capacity and stability of the structure to meet the probable maximum flood event. Installing 216 high capacity rock anchors was a major feature of the work.The USACE selected Brayman Construction Corporation to perform Phase 2B of the construction modifications to the Bluestone Dam. Brayman was responsible for installing the high capacity rock anchors, which range in size from 3 to 61 strands and have a design load up to 2,145 kips (9,541 kN). Drill holes range in size from 6.5 to 15 in (16.5 to 38 cm), and required full length corrosion protection. Of the 216 anchors, 57 were installed on top of the dam to resist overturning and the remaining 159 were installed on the face of the dam at a 45-degree angle to resist sliding.To gain access to the face of the dam anchor locations, the project required dirt benches, excavations with temporary shoring, and steel platforms. To access anchors on the east and west abutment faces, the team excavated over 10,000 cu yds (7,645 cu m) of material. Support of these excavations included the design and installation of three soil nail walls with over 145 nails and 3,500 sq ft (325 sq m) of shotcrete. The project also called for a 780 ft (237 m) long steel platform to gain access to the spillway anchors. The Stratus Group designed the platform to support two 85 ton (80 tonne) crawler cranes and as many as five drill rigs that were the equivalent to a design load of 3.5 ton per sq ft (335 kN per sq m). Once the final platform design was approved, fabrication of roughly 3 million lbs (1,360 tonnes) of structural steel began. Brayman’s in-house fabrication shop, in conjunction with Dura-Bond Industries and Advantage Steel, collaborated to fabricate and install the platform in less than five months. Flexibility in the platform design allowed for sections of the platform to be lowered as much as 16 ft (4.9 m) to provide access to anchors at lower elevations along the spillway face. In addition to the main spillway platform, Stratus Group, Brayman, Dura-Bond and Advantage designed, fabricated and installed six other unique platforms to facilitate anchor construction on various areas of the dam."

Jan 1, 2014

By Victor Dolmage

Introduction Although gold production in British Columbia began in 1859, lode gold was not produced till 1893. Since 1900, the annual production of lode gold has fluctuated between $3,000,000 and $6,000,000. About twenty per cent of this production may be regarded as by-product gold from base metal mining. The remainder comes from a few isolated but important mines, such as the Rossland mines, Nickel Plate, Surf Inlet, Premier, Pioneer, Bralorne, Reno, and Cariboo Gold Quartz, and from several less important mines. All of the above, except Pioneer, Bralorne, Reno, and Cariboo, are approaching or have reached the point of exhaustion, but all are now receiving, under the stimulus of the. present gold-mining boom, drastic resuscitative treatment, with, in some cases, signs of resurrection. Notwithstanding this, however, the main interest at the present time is focussed on the Bridge River and Cariboo fields. Both these fields were discovered in the early 'sixties' and, apart from the Cariboo placer production, both have from time to time contributed small amounts of lode gold; but it is only during the last two years that the real possibilities of these areas were discovered. and that they began to assume the appearance of goldfields of major importance. The two fields are sorme three hundred miles distant from one another and contain deposits of distinctly different types, so that the only reason for including them in one article is the fact that they came into prominence more or less simultaneously and at a time coinciding with, but not otherwise related to, the present gold-mining boom.

Jan 1, 1934

By A. J. Stapleton

"The Copper Mountain mine of Gaspe Copper Mines, Limited was brought into production in January, 1968.This paper describes the organization, scheduling and control of maintenance of large open-pit equipment, including 8-cu.yd shovels and 85-ton electric-wheel haulage units. The facilities for repair as well as maintenance are also described, including repair shops and field repair equipment. Maintenance costs are discussed and particular reference is made to tire inspection, records and costs."

Jan 1, 1969

By C. A. Young, J. D. Miller

Adsorption isotherms previously determined by in-situ Fourier transform infrared/internal reflection spectroscopy (FT-IR/IRS) for oleate adsorption at calcite and fluorite surfaces near pH 9 and at various temperatures are compared. Results indicate that, at both mineral surfaces, chemisorption occurs at equilibrium concentrations below approximately l x l0-5 M oleate while calcium dioleate surface precipitation occurs at higher equilibrium oleate concentrations. The extent of chemisorption at the calcite surface is 3 to 5 times less than that at the fluorite surface while the extent of calcium dioleate surface precipitation on calcite is nearly a magnitude larger than that on fluorite. However, for both minerals, surface precipitation decreases with increasing chemisorption. Contact angle measurements and flotation recoveries show the hydrophobicity of fluorite to be greater than that of calcite at each of the temperatures and oleate concentrations studied. Significant differences are noted only in the chemisorption region. Unlike calcite, the hydrophobicity of fluorite was sensitive to the presence of oxygen in the system. Multichannel Laser Raman Spectroscopy (MLRS) showed this behavior was caused by the double-bond reactivity of adjacent chemisorbed oleate molecules and subsequent formation of an epoxide/polyether complex at the fluorite surface. Such a reaction product could not be detected at the calcite surface. These differences in adsorption density, hydrophobicity, and polymerization behavior are discussed in terms of the intrinsic surface properties of the minerals.

Jan 1, 1999

By R. Carson Dalzell

The use of nuclear fission for chemical process heat offers the special advantage of high temperature, limited only by materials of construction. The process heat may be supplied economically at elevated pressures, since no compression of combustion air is required. For the initial effort in developing a high-temperature reactor, the indirect cycle, using helium as the heat-transfer medium, was chosen. The major problems are the design of high-temperature fuel elements, construction of an exchanger to transfer heat to process streams in the range of 2,500° F., and development of compressors capable of recycling helium at 1,000° F. and above. A conceptual design of a nuclear reactor to furnish process heat for coal gasification has been made. Spherical fuel elements utilizing a graphite structure, impregnated with uranium carbide fuel, were chosen, as spheres offer the possibility of easier loading and unloading of the reactor. Calculations of pressure drop and gas-pumping power for the system are included.

Jan 1, 1959

By J Pan, G Qiu

In this paper, an analysis is made of the present situation in the Chinese steel industry and its demand for iron ores. It is shown that the demand for iron ores has been growing substantially with the rapid development of the steel industry all over the world, especially in China. However, the iron ore market is currently in the situation where supply exceeds demand due to the economic crisis, with more investment in mines and less output of steel for several years ahead all over the world. Gigantic pressure is confronting the Chinese steel mills due to the too high and irrational price of iron ores. It is time to return the price of iron ores to a normal position much closer to their value. More attention has therefore been paid to developing low-grade and complex iron ore resources in China due to the irrational price of imported iron ores. More innovative mineral processing processes have been developed to tackle these complex resources. A systematic introduction to the development of beneficiation processes for low-grade iron ores is provided, including upgrading low-grade siderite, limonite, micron sized haematite and magnetite resources.

Jan 1, 2009

By Alice M. Chieruzzi

This Country Documentation Report presents the development of economic indices for the Philippines for the period from 1970 through 1981. The work was done through the Bureau of Mines, Minerals Availability Program, under Contract number J01225001. This contract calls for the development of twelve index time series describing factor input costs in the mining sector of 95 countries. The twelve index time series describe the costs of: 1) mining wages, 2) construction wages, 3) equipment and repair parts, 4) bits and related steel, 5) eimber and lumber, 6) fuel, 7) powder and balsting agents, 8) tires, 9) construction materials, 10) industrial materials, 11) transportation, and 12) electrical power. These indices combined with weight factors being developed by the personnel of the Minerals Availability Field Office (MAFO) of the Bureau of Mines in Denver, Colorado, will be used to perform instantaneous updates of all costs relating to the mining industry. The indices were developed primarily for use in the Bureau's Minerals Availability Program in assessing the worldwide availability of nonfuel minerals.

Jan 1, 1983

By T. M. Gurr

The United States is the world's leading producer of phosphate rock. In 1975 according to the US Bureau of Mines' statistics, 44.3 million tonnes (48.8 million st) of phosphate rock were produced in the United States, 1 which is 40.6% of the world's production.2 The major phosphate producing areas of the United States are located in Fig. 1 and the production for 1975 is listed as follows:

Jan 6, 1979

The Marvel Loch Operations (MLO) plant was treating ores from up to six MLO sources and in addition needed to blend externally sourced ores with its own ores. This presented a metallurgical accounting dilemma, which was subsequently addressed by the design, implementation and testing of an automatic sampling system. The MLO automatic sampler was well designed and has been the subject of previous internal and external reviews. The sampling action is fully automated and the unit is essentially self cleaning particularly when sampling primary ores. The purpose of this paper is to document the rationale behind the design, the specific details of the sampling station, its use for ore purchase purposes and an assessment of the sampling system to meet the needs of the operator.

Mar 1, 2010

By S Hapugoda, A Edenton, M Adam, R J. Holmes, J R. Manuel, R Smyth

Lump ore is one of the key ferrous feeds used in the blast furnace ironmaking process, normally accounting for ten to 20 per cent of the blast furnace burden. Like other feeds, the characteristics of lump ore have an important impact on the stable operation and productivity of the blast furnace. Lump ore is usually assessed chemically, physically and mineralogically to establish its likely blast furnace performance. The physical characteristics of lump ore are strongly related to the chemistry, mineralogy and texture of the ore involved. In this paper, the blast furnace ironmaking process is reviewed, with particular emphasis on the key quality requirements for the ferrous burden material. A variety of key physical characteristics of lump ore measured using standard and non-standard methods are then described and subsequently correlated with the chemical and mineralogical characteristics of the ore wherever possible. Finally, the impact of these physical characteristics on blast furnace operation is assessed.

Jan 1, 2009