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By R. H. Roberts

The Environment Weipa is located at 12° south latitude on the west coast of Cape York Peninsula, North Queensland, Australia. The climate is tropical with most of the 1 600 mm. average annual rainfall falling between November and March. During the short winter months (May/ August) the weather is clear and pleasant, with temperatures seldom exceeding 27°C.Throughout the remainder of the year, conditions are frequently oppressive due to consistent high ambient temperatures accompanied by high humidity. The terrain is of low relief, and generally not more than 6 to 10m. above mean sea level adjacent to the coast. The coastline features numerous short estuaries which discharge run-off from the heavy rains collected by creeks and rivers. The whole area is covered by an open forest, the predominant species of which is Eucalyptus tetradonta. These eucalypts have only limited commercial value and are heavily infested with termites. Despite the fact that Weipa is close to the location of the first reported sighting of the Australian coastline by a European (William Janz - 1606), it remains very isolated. There is no developed road or rail connection to centres of population, so that transport of practically all products, personnel and materials to and from Weipa is by sea and air. Cairns (population 49 000) is 580 km. by air and 670 nautical miles by sea; Brisbane, the

Jan 1, 1977

By Thomas C. Shapiro

This is the second in a series of articles on microcomputers and applications in the minerals industry. The first article (ME, Feb., page 129) discussed microcomputer terms and concepts. This article will discuss software for geology and mining. The third article will cover plant, administrative, and geotechnical software applications. Introduction Geology and exploration are areas where computers have a natural fit. Large volumes of data need to be tabulated, evaluated, and made into maps and reports that allow geologists and management to make a decision on a project or mine. Until recently, the programs that performed these tasks were cumbersome and not user friendly by any stretch of the imagination. Learning time to become an expert in these programs typically would be six months or more. The computers needed to run these programs are expensive mainframes. Several years ago, the use of minicomputers became popular because of their lower cost. Programs were adapted to fit these smaller machines and became friendlier. With the advent of micros, many programs. were rewritten and used the screen capability more effectively, thus providing a real advance in user interface. Programs and Price The definition of micro, mini, and mainframe is becoming blurred. For the purposes of this article, micro refers to either an eight- or 16-bit computer, costing less than $10,000 and, more typically, under $5,000. Mini refers to a 16- or 32-bit computer that typically costs more than $25,000. Mainframe refers to a 32-bit or larger computer that costs more than $250,000. There is a large gray area between micros and minis, and minis and mainframes. Technology and prices are changing so fast that the traditional definitions have become almost meaningless and price has become a better guide. With the arrival of the minicomputer, costs for hardware began to fall, but the programs have tended to remain unfriendly. In some cases, the minicomputer acted as a front end to the mainframe. Cost of both the programs and minicomputers could easily run a minimum of $70,000. A total cost of $200,000 would not have been out of line. The average geologist and company would have a great deal of difficulty justifying such a purchase. The advent of the microcomputer has changed all that. For $3,500 to $5,000, one can buy a 16-bit micro and a printer. Plotters with six pens are available for $2,000 that will produce a 280- x 430-mm (11- x17-in.) map. For several hundred dollars, software is available to act as a word processor, an economic spread sheet, or to perform ground water calculations. In fact, some programs are available for free. Some of these programs are relatively easy to learn. In addition, programs are being developed daily that are easy to use. More importantly, large programs that once ran only on mainframes are being converted

Jan 3, 1984

By Peter W. Lipman

Structural and topographic relief in the Sangre de Cristo Mountains of northern New Mexico provides a remarkable cross section through the recently recognized 23-26 m.y.-old Questa caldera and cogenetic volcanic and plutonic rocks. Although largely eroded, remnants of an ash-flow sheet of silicic-alkalic rhyolite and associated more mafic lavas of the Latir volcanic field are preserved as far as 45 km beyond the source caldera. Within the caldera, the tuff ponded to a thickness of 2-3 km and enclosed chaotic megabreccia fragments which slumped from the caldera walls. At the time of ash-flow eruption, the volcanic field was severely deformed along northwest-trending faults related to the Miocene Rio Grande rift, with most intense deformation occurring within the caldera. Strata were steeply tilted and locally overturned along presumably listric faults. Ash- flow tuffs locally underwent secondary flowage over concurrently developing fault scarps and accumulated within structural basins as rheoignimbritic lava flows. Cogenetic batholithic granitic rocks, exposed over an area of 20 x 35 km, range from mesozonal quartz monzonite to epizonal porphyritic granite and aplite, with the shallower and more silicic phases most abundant within the caldera. Compositionally and texturally distinct granitic phases define a highly evolved resurgent intrusion within the caldera, an incomplete ring dike along its southern margin, and a large mass of less fractionated quartz monzonite south of the caldera. A negative Bouguer gravity anomaly is closely confined to the area of ex- posed granitic rocks; it also reflects boundaries of the Questa caldera. The gravity anomaly is interpreted as defining the extent of the underlying batholith, emplaced into lower parts of the volcanic sequence and underlying Precambrian rocks. Paleomagnetic determinations indicate that the granitic rocks were above Curie temperatures at the time of caldera formation and regional listric faulting, yet most are little different in radiometric age from the intensely deformed volcanic rocks. These relations indicate that the batholithic complex represents the source magma body for the volcanic rocks, into which the Questa caldera collapsed, and was largely liquid at the time of regional tectonic disruption. Compositions of the volcanic and plutonic phases changed from early calc-alkaline metaluminous rocks, to weakly peralkaline silicic rhyolite and equivalent afredsonite-acmite granite at the time of the caldera formation, then back to post- caldera calc-riebeckite granitic rocks. Maximum concentrations of alkalis and minor elements such as Rb, Th, U, Nb, Zr, and Y were reached at the time the caldera formed about 25-26 m.y. ago, but the major molybdenum mineralization of the Questa district took place when the late calc-alkaline granitic ring intrusions were emplaced about 23 m.y. ago, along the south margin of the caldera.

Jan 1, 2013

By S. Asokan, D. Rathod, Ch. V. G. K. Murty

Tata Steel, a steel arm of Tata Group, is Asia's first and India's largest integrated private sector steel company. Tata Steel’s turnover in fiscal 2004-05 was nearly US$ 3.25 billion. As part of its vision to grow in related industries, Tata Steel is poised to enter the Titania businesses in the Indian state of Tamil Nadu. The Titania project will involve mining, separation of ilmenite & other co-minerals, beneficiation of ilmenite to synthetic Rutile and further maximum value addition to Titanium metal. This paper outlines the journey from the concept to current findings of the Bankable Feasibility Study in developing Sattankulam Heavy Mineral Sands Deposits in the State of Tamil Nadu, India by Tata Steel.

Jan 1, 2005

By F. Freme

Coal production in the United States in 2009 de-creased to 972.8 Mt (1,072.8 million st), according to preliminary data from the U.S. Energy Information Administration (EIA). This is a decline of 8.5 percent, or 90 Mt (99.1 million st) below the 2008 record level of 1.06 Gt (1,171.8 million st) (Table 1). In 2009, U.S. coal consumption decreased in all sectors while total coal stocks increased for the year. Coal consumption in the electric power sector in 2009 was lower by 10 percent, while coking coal consumption decreased by 30.6 percent and the other industrial sector declined by 16.6 percent. The commercial and institutional sector (which prior to 2008 had been called ?residential and commercial?) is the smallest of all the coal-consuming sectors and it declined by 8.4 percent in 2009. (Note: all percentage change calculations are done at the short tons level.) U.S. coal exports fell from the 2008 levels, while coal imports decreased for a second year in a row. The decline in coal consumption during the year was the consequence of the domestic economic conditions combined with the weather in 2009, which resulted in lower demand for electricity. Preliminary data show that total generation in the electric power sector (electric utilities and independent power producers, including useful thermal output) in the U.S. decreased in 2009. Coal-based generation also decreased, resulting in a 94-Mt (104-million st) drop in coal consumed in the electric power sector. Coal use in the non-electricity sector decreased by 20.1 percent to a level of 57.9 Mt (63.9 million st). The international coal markets for most of 2009 were reflective of a worldwide economic slowdown. U.S. coal exports and imports both declined for the year. U.S. coal exports totaled 53.6 Mt (59.1 million st). This is a decrease of 20.3 Mt (22.4 million st) from the 2008 level.

Jun 1, 2010

By S. H. Jason Choi

The Systems Conveyance and Operations Program (SCOP) is being implemented to convey tertiary-treated effluent to Lake Mead near Las Vegas, Nevada. The Reach 3 Tunnel Project is part of SCOP. The tunnel?s planned location along and across the Las Vegas Wash creates challenging tunneling conditions. A number of feasible excavation and initial support methods are being considered during the final design stage. This paper describes how the tunnel construction options were refined based on anticipated tunneling conditions and compatibility between tunnel excavation and initial support methods. A brief description of the most significant characteristics of the anticipated ground conditions is included for the purpose of discussion.

By D. D. Harbuck

Previous studies at the U.S. Bureau of Hines have shown that only 70 to 80% of the germanium in domestic zinc process residues can be extracted during H2S04 leaching. To increase germanium extraction, the Bureau developed and researched the hypothesis that minor amounts of germanium and zinc silicate, both present in zinc calcine, dissolve during the leaching stages of zinc processing, forming soluble germanium and silica gel. This silica gel then selectively adsorbs germanium from solution, rendering the germanium insoluble. Testing showed that as the amount of silica gel formed increased, the amount of insoluble germanium in the zinc residue increased. Several processing alternatives are presented for overcoming this problem.

Jan 1, 1991

By J. Y. Hwang

Processing of fine mineral particles in a slurry is a difficult problem. Methods to make fine particles magnetic have been developed recently and may offer a solution to this problem. Particles of nonmagnetic materials can be selectively rendered magnetic through surface interactions with magnetic reagents. When adsorption occurs, the magnetic susceptibility of the material is increased. Magnetic enhancement at several orders of magnitude can be achieved. Selectivity of the adsorption can be controlled by the functional groups of magnetic reagents and various surface interaction mechanisms. This approach allows a new degree of freedom for the processing of fine mineral particles, even with conventional magnetic means. Separation of valuable minerals and filtration of slimes from tailing ponds and recirculated water are examples of the applications. Basic principles of this technology are discussed in this study.

Jan 1, 1992

By A. I. Johnson

The pegmatites of the Black Hills of South Dakota are the coarse-grained differentiates of the Harney Peak Granite. The Harney Peak Granite was intruded into the Pre-cambrian schist and quartzites and resulted in the Black Hills uplift. In the outer adzes of the granite intrusion occur the pegmatites. In the zoned pegmatites, representing the most highly differentiated portions of the parent magma, occur most of the minerals produced from pegmatites. These are of economic importance and they are the subject of this paper. The various mineral products will be taken up separately.

Jan 1, 1978

By Jr. Bacon

Kaolin clay is one of the yeoman minerals. It sees duty in almost every aspect of our lives: -in and on most paper products (from modern newsprint to National Geographic and packaging board) sometimes as much as 25% (by weight) of the product -40% of the tile (ceramic, rubber, and linoleum) you walk on. -15 % of the tires you ride on, -30% of the fiberglass filaments in circuit boards, bathtubs, boats, doors, and more, -25% of many housepaints, adhesives, grouts, caulks, and putty -30% of sparkplugs, power insulators, dinnerware. and toilets, -50% of most catalysts (both cracking and emission control) -20% of cosmetic powders. -20% of wire insulation, and animal feed to rocket insulation!

Jan 1, 1993

By S. Uihteenmaki

Pyhasalmi is a massive sulfide orebody located in central Finland. The mine has been in operation since 1962. The flotation concentrator produces Cu, Zn, Pb and pyrite concentrates. The plant has used an on-stream analyzer for process control since 1968. The original analyzer has overlived a few generations of minicomputers, but the analytical parts are essentially unchanged. The on-stream analyzer is a critical component in plant process control system, which has made Pyhasaltni one of the pioneers in the art of computer control and optimization of flotation plants. The paper summarizes the experiences gained from the use of the high performance elemental analyzer system and the proven benefits from the use of on-stream analyzers at a complex sulfide flotation. The aging analyzer is approaching the end of its useful life. A new state of the art analyzer system is undergoing testing at Pyhasalmi.

Jan 1, 1999

By Vincent Tricot, Daniel Altier, Roger Storry

"INTRODUCTION The Liantang / Heung Yuen Wai Boundary Control Point (BCP) project, located in the north-east New Territories of Hong Kong, will form the seventh land crossing between the Hong Kong Special Administrative Region (HK) and Shenzhen in China (Figure 1). The BCP project comprises an 11km long dual two-lane trunk road linking the border crossing facility to the existing road infrastructure in HK and when completed it will facilitate future regional development and alleviate frequent traffic congestion at the existing Boarder control points.In December 2013 Dragages Hong Kong (a member of the Bouygues Construction Group) was awarded the 5.4km long Contract 2 section of the project, including the 4.8km long Lung Shan Tunnels, by the Civil Engineering and Development Department of the Government of the HK SAR. To overcome the difficult ground conditions anticipated along the Contract 2 section of the project the tunnels will be constructed using mechanical and drill and blast (D&B) excavation techniques together with a 14.1m diameter multi-mode Earth Pressure Balance Tunnel Boring Machine (TBM). Land constraints imposed on the project alignment require that the final 500m section at the northern end of the Lung Shan tunnels, under Princess Hill (Figure 2), takes an almost 90 degree turn towards the north. The resulting 354m radius curve restricts the sight-line of road users to below the minimum 110m at 80km/hr hence, the internal span of the tunnels needs to be increased from 12.6m, in the standard straight section, to 15.4m in this curved section to accommodate a widened shoulder which will provide the required sight-line distance."

Jan 1, 2016

Tracer gases are an effective method for assessment of mine ventilation systems, but their dispersion characteristics can differ substantially as ventilation parameters, such as flow path and velocity, vary. This research utilizes Computational Fluid Dynamics (CFD) to model a simplified full scale model mine, details a sensitivity study examining mesh size for an underground coal mine simulation, and examines gas dispersion parameters to determine the optimal model methods for simulation of tracer gases in underground coal mines. These models can be used to determine how a given tracer gas profile might be generated in a mine or areas of a mine that are not accessible, for example, immediately following a mine disaster. Accurate simulation scenarios can allow for the remote determination of the status of the ventilation network, but the sensitivity of the simulation at mine scale must be carefully examined.

Jan 1, 2012

By V. Bush, T. G. Killingsworth, E. P. Ruffel

Effective and sustained corporate energy management programs are becoming a necessity for energy users as electricity deregulation laws are enacted on a state-by-state basis across the country and environmental regulations pertaining to emissions become more prevalent. The “Total Energy Asset Management” (TEAM) approach has been developed to assist energy end users with the development and implementation of corporate energy management programs designed to reduce energy risks and increase energy cost savings. This paper highlights the ways in which this approach can be applied to the mining industry while minimizing initial program implementation costs and increasing potential program benefits. Nearly the entire mining industry has become very focused on identifying opportunities to reduce costs per unit of yield. The industry as a whole has increasingly faced pricing pressures in large part due to the effects of global competition. The result of international marketplace participation and the emergence of higher efficiency recovery techniques have resulted in flat or even decreased prices for mining products. Thus, opportunities to reduce costs are actually opportunities to gain a competitive edge over similar mining operations. Due to the energy-intensive nature of many mining operations, the costs associated with energy are often a substantial percentage of operating costs. Therefore, it becomes very important to develop the corporate mentality that energy is an asset whose use should be optimized globally. In addition to the cost benefits of the TEAM approach, other benefits may occur such as reductions in facility greenhouse gas emissions.

Jan 1, 2002

By R. C. Ford, W. L. Niccoli, J. B. Finley

All mining operations are superimposed on natural hydrologic systems. As a result, mining operations are influenced by natural hydrologic processes and require water management systems to successfully conduct mining activities. Managing water and mining-related solutions is a critical task at all stages of the mine life because of the time-dependent nature of natural and mining-related flows. Effective operation of the mining water management system requires a “systems” approach that integrates the time-dependent effects of all water and mine solution handling components. This paper discusses the concept and application of dynamic systems modeling to address the time dependent nature of mining water management systems.

Jan 1, 2002

By Y. P. Chugh

During late 2010, a scientifically founded water spray system was developed for continuous miners (CM) (Patent Pending) that reduces respirable dust exposure for miner operator by about 30%. It includes engineered sprays around the cutting drum, outer bit-ring sprays, chassis sprays and side cutter boom sprays. About 3.6 ? 4.5m (12-15 ft) behind these sprays is additional sprays that spatially cover the area between the CM chassis and the mine roof and ribs. The spray system uses approximately the same volume of water as currently used on CMs with similar operating pressures. An Illinois mine decided to implement these concepts on a CM during rebuild stage. Dust control performance of the rebuilt CM was evaluated using gravimetric sampling and real-time monitoring using multiple personal dust monitors (PDMs). The average results based on about 105 cuts show about 30% and 20% reduction in dust exposure for the miner operator, and the haulage unit operator. Visibility in the mining areas was also significantly improved. The coal company has already decided to implement the system on all their CMs.

Jan 1, 2012

By K. W. Grubaugh

Indigenous people are nearly always affected when projects enter their territory. Crop and other asset compensation can help or undermine a project’s progress depending on the approach. When compensation is handled poorly, a technically viable project can get indefinitely entangled by local unrest. Stake holders associated with compensation issues include; the state, the indigenous people, non-governmental organizations, and the developer. Appreciation for the unique perspective of indigenous peoples and the influences affecting them can avert problems and prevent delays. A review of the compensation issues encountered in Ghana during its recent gold boom can assist in avoiding problems associated with handling poor and uneducated people.

Jan 1, 2002

By A. E. Koski

Two of the largest industries in northern Michigan, pulp and paper manufacturing and iron mining, formed a mutually beneficial partnership and collaborative research program to utilize paper mill residuals for waste rock stockpile reclamation. Historically, the majority of the paper industry’s residuals have been disposed of in landfills. The beneficial use of paper mill residuals for mine reclamation provides an environmentally sound recycling solution for the solids generated at northern Michigan paper mills and eliminates the need to strip additional overburden (glacial till) for final mine reclamation. Residuals offer a cost-effective source of organics and nutrients necessary for successful reclamation and waste rock stockpiles offer an economical and environmentally sound solution for disposal of residuals. The goal is to successfully pioneer technical development of paper mill residuals to accomplish vegetation of steep waste rock stockpile slopes and benches to establish a self-sustaining plant community that meets final reclamation requirements. Of the various types of iron mining wastes, rock stockpiles pose the greatest reclamation challenge. Success depends on incorporating sufficient organic matter into the rock stockpiles to produce a growth medium that can sustain vegetation without the need of overburden. This is an ongoing research program that is evolutionary in nature with numerous field trials, greenhouse studies, data collection and monitoring over multiple growing seasons. The program is a combination of innovative ideas and accepted reclamation practices that is proving to be a beneficial and economic approach to paper mill residual management and mine reclamation that will eventually lead from research to standardized reclamation procedures.

Jan 1, 2006

By Maurice Grieves

GC. Waterman Mr. Grieves' paper on "Shaft Sinking Today--A Boring Business Tomorrow" in the Dec. 1981 issue of MINING ENGINEERING is an excellent description of recent improvements in speed and costs of shaft sinking. However, shaft boring techniques are not a recent development. In 1935-36, the Idaho Maryland Co. (gold), Grass Valley, CA, bored the vertical 1.5-m-diam Idaho No. 2 ventilation and supply shaft to a depth of 346 m. The equipment was designed and perfected by Branner Newsome and was, I believe, described in "Transactions." Pickands Mather later bored a 1.8-m-diam shaft to a depth of about 305 m using Newsome's design. The Idaho No. 2 shaft cut through hard gabbro, diabase dikes, soft serpentine, very incompetent ankeritized serpentine and a strong fault zone. The completed shaft did not require timber support; the fault zone was cemented. Equipment consisted of a rotating 1.5-m or 3-m core barrel with a slotted bottom which cut a 76-mm kerf. The cutting agent was chilled steel shot introduced into the slot as needed. The driving mechanism and core barrel were lowered into the shaft, the former secured to the wall and the inshaft "engineer" operated the motors which controlled core barrel rpm and advance. After an advance of 1.5-3 m the equipment was lifted out of the shaft, a half(?) stick of powder cut off the drilled core, and it was hoisted to the surface with a cable attached to an eye bolt at the tope of the core. A "shift" consisted of three men: hoistman, equipment operator (down the shaft), and a surface laborer. Advance was variable as equipment and techniques were perfected. Near the end of the job advance was, as I remember, 1.5-3 m per shift. Costs were, as I recall, about $115/m. Up to 4 m cores were lifted out in one piece and swung to the dump by a stiff leg derrick. The Newsome equipment was relatively inexpensive to build and operate and his method should be (more than?) competetive with the methods described by Grieves. W.E. Hawes The author, in mentioning the South African developments of the cactus grab, ignores the parallel development of the Cryderman mucker in this hemisphere. Perhaps a slightly longer history of blind hold drilling would have been in order. Blind shaft boring got a major boost at the Nevada Test Site, as part of the nuclear weapons development, when it was essential to be able to quickly assess depth for weapons testing. One of the early civilian attempts to utilize this technology occurred when Kerr McGee drilled the shaft at the Section 19 Mine at Ambrosia Lake, NM. This twin masted drill rig belonged to a subsidiary of Kerr McGee, not Shaft Drillers. This was a difficult hole, due to bentonitic shales that decomposed. Later advances in drilling fluids eliminated this problem. The Conoco project referred to is not entirely correct, and needs minor amplification: The depth of the development (not pilot) shaft drilled was 684 m, at a diameter of 3.05 m, with a 2.16 m ID hydratatic casing being installed to a depth of 669 m. Conoco Inc., not Challenger, executed the drilling, however Conoco did use Challenger Drilling Company's Rig 14-S. Rig 14-S is unique in that it is specifically designed for shaft drilling, rather than being an oil field rig used for this service. All work was planned and directed by Conoco personnel. Deviation of the aforementioned shaft from vertical was 31 cm. Two smaller shafts (pilot shafts) were drilled with the same rig. These smaller ones were drilled 1.8 m in diameter, to depth of 665 m and cased with .91-m-diam casing, to depth of 650 m to be used as pilot holes for 5.5 m diameter shafts. The total elapsed time for all drilling, casing, cementing, and rig moves was 50 weeks. The constraints mentioned of vertical accuracy, torque, wall collapse, rig set up time, lining time etc., pumping out, etc., may not be as serious as the author implies. First, vertical accuracy: The record achieved by Conoco indicates that with reasonable care, good accuracy can be obtained, primarily by having a fair amount of weight in tension, rather than on the drill bit. Second, the amount of torque that can be applied to the drill stem has been greatly increased by the introduction of larger diameter drill stems, such as the new Hughes rig uses. Third, risk of collapse of shaft walls is minimal with the proper mud program. Basically, the walls are supported by the weight of the mud and it is not removed until some type of casing is installed and grouted in. Here in the real challenge of blind drilling shafts to devise a more economical method of lining bored shafts than using steel casing. The remaining issues were minor at Conoco, provided adequate planning and scheduling takes place. An excellent paper, "Shaft Drilling--Crownpoint Project" by Hassell H. Hunter, presented at the Fifth Uranium Symposium in Albuquerque in Sept. 1981 contains details of this project. A combination of blind boring, with enlargement by either mechanical means (boring machine, or tunneling type shield) or slabbing down, with muck removal through a larger bored shaft would seem to be the future trend in shaft development. The economics, especially for wet conditions, favor this concept over conventional sinking, as has been demonstrated at Kerr McGee --Churchrock, UNC--Churchrock and Conoco at Crownpoint.

Jan 3, 1983

By C. Restarick, R. G. Robins, R. M. Taylor, I. Ennis

Lime addition to acid mine drainage waters (AMD), possibly accompanied by aeration, has been the basis for their remediation by precipitation of predominantly metal hydroxides. An efficient novel alternative technique causes precipitation of double M(II)-M(III) hydroxy sulfates which readily precipitate and are easily dewatered. When the Fe(II)/Fe(III) + Al(III) ratio of the AMD is appropriate, the Green Precipitate (GP) Process provides a more effective alternative to normal liming/aeration. The process can be adapted to give a continuous in-line treatment by the choice of suitable computer-controlled reactors designed to improve the liming efficiency, reduce scaling and control the rate of treatment. The processes are described in terms of the chemistry involved.

Jan 1, 2000