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By Anibal Gajardo

Because of the Chilean Ministry of Mining's interest in the development of industrial minerals, the Chilean Geological and Mining Service (Servicio Nacional de Geología y Minería, SERNAGEOMIN) has carried out a research program during the last two years to identify projects that represent interesting investment opportunities for small- to medium-scale operations in Chile. Most important of these projects are: (1) Quebrada Lluta aluminum sulphate, for drinking- and industrial-water treatment, with a potential domestic and foreign mar- ket of almost 43,000 tonnes per year and investments of about US$1.8 million; (2) Quebrada Lluta-Quebrada Cardones pumice, for abrasives, filters, fillers, and light- weight aggregates, with a potential market of about 30,000 tonnes per year, and in- vestments of US$2.0 million; (3) El Maule dolomite, for soil conditioner and iron smelting, with a total potential domestic market of some 60,000 tonnes per year, and estimated investments of US$2.0 million; (4) Las Escaleras bentonite, for animal feed, pelletising, and oil absorbents, with a potential market of almost 6,000 tonnes per year, and investments of about US$2.4 million; (5) Laraquete-Carampangue andalucite, for alumina refractories, with a future total domestic and foreign demand of about 15,000 tonnes per year, and estimated investments of US$2-2.5 million; (6) Rio Lía garnet, for fillers and sand-blasting abrasives, whose domestic market represents 10,000 tonnes per year, with investments of US$2.3 million; and (7) Munilque pumice, for building bricks and panels, with a potential domestic market of 250,000 tonnes per year, and investments of US$1.4 million. The development of these projects will represent an important increase and a significant diversification in Chilean industrial-minerals production.

Jan 1, 1999

By Will Foreman, Douglas D. McLearie, Edwin K. H. Tong, William H. Hansmire

Hong Kong’s Strategic Sewage Disposal Scheme (SSDS) Stage I involves the provision of a system of deep tunnels for transporting to a central treatment works wastewater collected from a number of catchments around Victoria Harbour. For the SSDS Stage I works, about 24 km of tunnels have been excavated in hard rock at depths ranging from about 80 to 150 m below Victoria Harbour and the surrounding heavily developed areas of Kowloon and Hong Kong. Five tunnel boring machines(TBMs) with diameters ranging from 3.2 m to 4.3 m were used to excavate the tunnels. Tunnel excavation has been completed and tunnel linings are in progress. Major tunnelling issues such as ground stabilisation and water control encountered in the project are summarised. An overview of one of the possible future tunnel systems that might be adopted in subsequent stages of SSDS is also presented.

Jan 1, 2001

By L. H. Pye

For large mining sites in the west, the traditional method for performing an ecological risk assessment (ERA) provides little useful information for risk managers faced with selecting and designing sound remedial options. Current U.S. Environmental Protection Agency (EPA) risk assessment guidance largely supports quantitative risk characterization of individual species as surrogates for population and ecosystem-level effects. Developing a work plan for investigating and remediating ecosystem-level changes potentially caused by large-scale historic mining/smelting contaminant release requires a decision process that incorporates a more holistic ecosystem management approach. Some of the most wasteful efforts associated with mine site ecological risk assessments arise when the risk analysis and data collection programs are not specifically linked up-front to the risk manager's decision needs. The following paper discusses the importance of employing a decision-based, ecosystem management framework when conducting ecological risk assessments at large mining sites. A case study of an ecological risk assessment currently being performed at a large New Mexico copper mine site is presented.

Jan 1, 1999

By Dermot M. Ross-Brown

The more important factors controlling the design of pit slopes are related to the local geology over which the designer has little or no control. Nevertheless, there are some factors over which the designer does exert some control and these concern the say in which the rock is excavated and supported. They include blasting, face cleaning, water control, and the use of rock improvement techniques. The paper discusses these factors and relates the extra costs incurred to the steeper slope angles that can usually be obtained. It is demonstrated that even a modest increase in bench angle of 5° through improved excavation techniques can pay off in a single push-back.

Jan 1, 1975

By Peter Loehr

Full-face tunnelling machines were introduced into German coal mines 12 years ago. It was aimed to utilize these highly efficient systems to drive mine tunnels in rock so that the large demand for development work in some mines could be met. A characteristic feature of coal deposits in Germany - and particularly in the Ruhr Area - is a thick overburden strata. Access is therefore only possible through vertical shafts. A network of horizontal drivages leading from these shafts open the deposits between the different mine levels. The hardcoal-bearing formations are multi-folded and heavily tectonically stressed. Apart from a few extensive fault zones there are many single faults of different natures in the carboniferous strata. During the course of decades coal mining has penetrated to ever increasing depths. Nowadays coal is mined from depths of between 600 m and 1,200 m. The effects of ground pressure in connection with extremely varying rock strengths and high temperatures are particular difficulties which have to be overcome during drivage work. The first full-face tunnelling machines to be applied in the mines had originally bee deigned and developed for tunnelling projects. Not only the machines themselves, but also the back-up equipment had to be adapted to meet the special demands of German coal mines.

Jan 1, 1983

By Michael Rehbock-Sander, Romed Insam

"INTRODUCTIONThe idea of building a summit tunnel under the Brenner occurred to the Italian engineer Giovanni Qualizza as far back as 1847. But it was to be another 160 years to pass before a base tunnel was to be built.In 1971 the idea of a tunnel at the Brenner was dusted off again. The UIC, the International Union of Railways, commissioned a study for a new Brenner railway with a base tunnel. By 1989 three feasibility studies had been drawn up which formed the basis for further planning of the Brenner Base Tunnel.This was the start of the planning activities. In 1994, the European Union included the Berlin-Naples corridor in the list of priority projects. Ten years later, Austria and Italy signed a State Treaty to build the Brenner Base Tunnel. In that same year, what is today the BBT SE was established.PROJECT DESCRIPTIONThe Brenner Base Tunnel (BBT) with a length of 55 km is the centrepiece of the Helsinki-Valletta Transeuropean Traffic Corridor from Finland to Southern Italy. The BBT tunnel system connects in the north with the Innsbruck station (Austria) as well as to the feeder routes in the Lower Inn Valley, and opens to the south with the projected new line in the direction of Verona (Italy). The tangible design efforts have been underway since 1999; the start of construction of the first section was in the year 2007. The project is financed by the Italian and Austrian governments (each 30 %), as well as by the European Union (40 %).From 2027 onwards the Brenner base tunnel, including the existing lines connected with it, will carry a daily average of 330 trains (approx. 80% cargo trains and 20% passenger trains)."

Jan 1, 2016

By C. S. Kucukkaragoz

An ilmenite concentrate was reduced in the solid state with carbon under argon atmosphere at temperatures between 1000oC and 1400oC. The ilmenite concentrate and 50% excess carbon were reacted to achieve the highest attainable degree of reduction at each temperature and the reaction products were subjected to a series of analytical work by optical microscopy, X-ray diffraction analysis and SEM ( EDS) analysis. The ilmenite remained unaltered at 1000oC and had a slight change in its composition at 1050oC. A secondary oxide phase containing metallic nuclei was detectable at 12% reduction at 1100oC. The reduction of TixOy took place in a sequence changing the y/x ratio from 2.0 to a value less than 1.0 at 84% reduction at 1400oC. Metallic phase consisted of Fe and C initially and started to include Ti at the later stages. Complete reduction of TixOy to metallic Ti was not possible at these temperatures.

Jan 1, 2005

By D. Bernabe

The mine scheduling process defines a mining sequence across the life of the mine and stipulates the amount of ore, waste, and specific blocks to be mined each year so that the highest economic return can be obtained under a number of constraints. There are a number of mine scheduling software packages available. Each claims to be the best scheduler by maximizing Net Present Value (NPV) or by minimizing overall mining costs. These mine scheduling programs follow different procedures and scheduling philosophies based on either mathematical or heuristic principles. There was no study in which the mine production scheduling procedures applied by these packages were discussed and compared. This paper evaluates four open pit mine scheduling programs recently developed and compares them in order to determine if significant differences exist among them. The same input data, which consist of a 3-D block model, an economic set of parameters, and the initial surface topography for a operating copper mine in Southern Peru, was used to test each technique. The following programs were investigated with respect to their ability to optimize the NPV for the case study. 1) M821V1 Scheduler by Mintec; 2) NPV Scheduler by Earthworks; 3) Milawa Scheduler by Whittle Programming; and, 4) Fundamental Tree Scheduling Method (FTSM) developed at the Colorado School of Mines. The results from this case study demonstrate that the scheduling software packages, Mintec, Earthworks, and Whittle obtained similar NPV’s, while FTSM scheduler gave a six percent higher NPV than the other schedulers.

Jan 1, 2002

By Paul W. McGann

This paper presents a methodology for long-range studies of petroleum supply, to meet projected demands, that involves modifications of procedures used previously. This paper continues a series of papers on this general topic in the AIME, the most elaborate recent one being that by Warren Davis given in February 1958. The procedures considered here begin with the assumption that the governmental framework of regulations and taxes remains fixed- but that price changes. After .these procedures have been reviewed, the effects of changing certain governmental controls, will be considered in order to judge their potential effects on future supply. This is an essential step because controls cannot be expected to' remain static in a situation changing as much as the petroleum. industry and because such changes are within-the scope of alternative ways of adjusting to impending problems. The first procedure begins with: a) trends in drilling success, b) relation between field income from oil and gas and footage drilled, c) declines in capacity from production, d) trends in capacity of new and producing wells, e) all monetary values are in constant 1958 dollars, and f) target amounts of domestic crude petroleum production. 'From these components projections are obtained of: 1) numbers of future producing wells required, 2) footage drilled, 3) new wells drilled, 4) crude oil found, 5) capacity of producing wells, 6) completion costs, 7) finding costs, 8) production costs, and 9) average wellhead crude oil price consistent with the footage-field income relationship.

Jan 1, 1960

By M. S. Klima, A. Simard, M. L. Turek

Laboratory testing was carried out to evaluate several devices for recovering clean coal from bituminous coal refuse material. The bulk of the testing focused on using a dense-medium cyclone to process -0.6-mm refuse material. A hindered-settling column and a spiral concentrator were also used to process 1.2x0.15-mm material. Product yields and ash contents were obtained for all tests, while partition curves were generated for selected tests from which the characteristic performance parameters (relative density of separation and probable error) were determined. The results indicated that the dense-medium cyclone was capable of cleaning down to 0.037 mm, while the other devices were effective to 0.15 mm.

Jan 1, 2002

By William G. Pariseau

Few departments of mining, metallurgical or petroleum engineering in the United States have critical mass. Cost per student credit hour (SCH) in departments across the country are usually the highest among engineering departments, which are the highest on campus. Almost all departments are operating at fixed costs and enrollments could easily double without incurring much additional cost. However, the cost per SCH would remain unacceptably high and the probability of doubling enrollment is nil. Declining enrollment is a more likely future. The pressure to reduce SCH from university administration is unrelenting. And it has the potential for doing serious damage to program quality when standards and requirements are lowered in attempts to maintain enrollments and increase retention.

Jan 1, 2002

By Kirk L. Prather

Why discuss techniques of accident prod lot on? Would it not be more useful to discuss means to reduce accidents? This discussion will answer these questions by suggesting ways in which effective accident prediction techniques improve the ability to foresee and prevent accidents. Accident Prediction Process The secret to accident prediction is to utilize the tendency for history to repeat itself. The same circumstances and the same human behavior that produced accidents in the past tend to produce accidents in the present and the future. The ability to predict accident occurence in the future by projecting from the past is a statistical process. In a bookmaker's jargon this means "playing the odds" or "the percentages". A horse or a sports team may be beaten on any given day, but by skillfully assessing the factors of past performance and assigning odds, many clever bettors make money in the long run.

Jan 1, 1973

By G. R. Erdman

The industrial mineral filler plant of the Gouverneur Tale Company is equipped with a good dust collection system installed long before the recent popularization of environmental pollution. Credit for this fact is due to the foresight of Mr. R. S. McClellan, Project Manager and subsequent Vice President and General Manager of Gouverneur Talc, who recently retired as Vice President Engineering of the parent organization, the R. T. Vanderbilt Company. Also instrumental in the early stages of plant operation and the solution of start-up problems was J. A. Gustin who is now an engineering consultant located in Martinsville, Va. Credit is most certainly due to the late R. T. Vanderbilt, the company's founder, who favored and approved the investment in the necessary facilities that were far ahead of all competitors in the industry at that time.

Jan 1, 1972

By Lawrence Tsang, Conrad Ng, Tim Leung, Peter Poon

"The Mined Tunnel is part of the Central-Wan Chai Bypass and Island Eastern Corridor Link (CWB), which is a strategic road along the northshore of Hong Kong Island targeted to alleviate the heavy traffic congestion. The objective of this paper is to review the performance of construction of a 160m long Mined Tunnel with a trinocular cross-section area of 460m3 and a combined span of about 50m underneath the southern approach ramp of the existing Cross Harbour Tunnel (CHT) by sequential excavation method (SEM) in hard rock. Mechanical excavation of tunnel by adopting the New Austrian Tunnelling Method (NATM), together with the application of NGI Q-system allows observational approach and optimization of temporary rock support design. Furthermore, the good performance of optimized rock support and the stability of CHT are confirmed through instrumentation monitoring review. This paper also discusses the selection of different tunnel plant and equipment to achieve the planned rates of tunnelling by mechanical excavation in competent granitic rock. INTRODUCTION The works of the CWB mainly comprise construction of 4.5km dual three-lane trunk road, of which a 3.7km section is a tunnel connecting Rumsey Street Flyover in Central to Island Eastern Corridor at North Point (see Figure 1). The Mined Tunnel runs from the ex-Public Cargo Working Area (ex-PCWA), underneath the existing CHT, and through the Causeway Bay Typhoon Shelter. The Mined Tunnel passes at an oblique angle beneath the southern portal of CHT over a length of some 50m. CHT is the primary sensitive receiver of this project and is utilized with a daily throughput of about 120,000 vehicles that far exceeds the design capacity of 78,000 vehicles per day. Hence it is necessary to choose the most appropriate tunnelling method to preserve the structural integrity of the CHT. Other sensitive receivers in the vicinity include structures to the north of the Mined Tunnel, the Royal Hong Kong Yacht Club (RHKYC); and to the south of the Mined Tunnel, the Police Officers’ Club (POC)."

Jan 1, 2016

By D. G. Chedgy

Careful consideration is given to the type of cleaning equipment and control sys- teas to be used when selecting circuits for wash-ing fine coal (28M x 0 size fraction). However, the desliming, declaying and sizing procedures required to ensure efficient operation normally are not evaluated in sufficient detail resulting in disappointing system performance. This paper details desliming and dewatering circuit design which is extremely effective based on recent test data. The circuit maintains control of the 28M x 0 (declayed) size fraction with minimal misplaced material and maximized circuit efficiency. A discussion of circuit design parameters and control systems, as well as results from the testing program, are included in this text.

Jan 1, 1986

By Yinan Zhang, Yi Luo

The widely used R70 method is modified to measure the self-heating propensity of low-rank coals. This modified R70 method enables the introduction of controlled amount of moist oxygen into the reaction vessel. Three coal lumps were collected from three different locations in a surface mine in the Powder River Basin. The coal samples were tested in oxygen flow with controlled moisture content under adiabatic condition. By measuring the relative humidity at the exhaust exit point of the testing setup, the flux and cumulative wetting heat that is consumed by coal samples can be determined. Through a better way of determining the coal’s specific heat, the total heat, including heat of wetting and coal’s oxidation heat, required to raise coal to a given temperature can be determined. Then, the contribution of heat of wetting at the different stages of the testing is quantified. The effects of evaporative heat through a group of tests have also been quantified. From this research, a better understanding of the effect of wetting heat on inducing low-rank coal’s spontaneous combustion can be acquired.

Nov 30, 2022

By Thomas E. Howard

Engineers today face a tremendous challenge. Growing population and rising standards of living all over the world are creating unprecedented and accelerating demands on and for all kinds of technology. At the same time, the public is becoming more and more conscious of--and concerned with--the impact of technology on human welfare. The growing controversy over the Supersonic Transport is a case in point, It is clear that the modern engineer must expect to spend a growing share of his time considering this dilemma and evaluating the tools that are available to him, not only with respect to their adequacy for the job at hand but also their capability for meeting the increasingly demanding--and, in many cases, conflicting--requirements of the future. This meeting seems a particularly appropriate place to speculate about the future of mining technology. The summary of the state-of-the-art in surface mining contained in the papers scheduled for the International Conference, together with the recently published Surface Mining volume, constitute not only a major contribution to the technical literature but also form an impressive record of technologic progress. That record, and the advanced technology displayed in the exhibits, and to be discussed in the SME technical sessions demonstrate engineering achievement in which the mining community can justly take pride.

Jan 1, 1968

By T. E. Kobrick

When Ralph Banks called and asked if I would agree to present a paper on environmental health in the coal industry, I was reluctant because I have not been actively involved in coal mine dust control on a day-to-day basis for a number of years. Ralph reminded me that I am one of the few industry people with an industrial health background who remembers the pre-1969 Federal Coal Mine Health and Safety era. This marks the second time within the past year that I have had a similar request based on the same basic reasons. While I was pleased to have been remembered, I'm beginning to feel like the football player who has played one too many games. In responding to Ralph's request to present an overview of the past, present and future of environmental health in the coal industry, I have attempted to take the broad approach of someone who, having been intimately involved in an area of endeavor for a number of years and then leaves, has an opportunity to revisit that area at a later date to see what has changed and what remains the same, what have been the successes and the failures. Since none of us can foresee the future, trying to project too far ahead is fraught with frivolity, except that unless one is foolish enough to accept a future invitation to review those predictions compared to actual events, no one will recall how accurate or inaccurate those projections might have been. I can assure you that I will not ask to accept that challenge, so you can rest comfortably that five years from today you will not be asked to sit through a similar presentation by me - and that's a promise.

Jan 1, 1985

By Phillip J. Maddex

After the presentation of a co-authored paper, "The Cost of Transporting Ores and Raw Materials in World Markets", at the February SME meeting, one questioner commented, "You have been talking about the large shipper and ship loads. What does the small shipper do?" This paper will attempt to answer that question, at least in part. Probably the questioner hoped to hear about specific new tools and new techniques that he could apply. But one paper could only scratch the surface of the vast fund of information available; so rather than talk specifics we should take basics, that is, people, management and technology.

Jan 1, 1967

By C. H. Sheerin

Remotely located in the jungle near mount Puncak Jaya [16,500 ft (5,030 my), Irian Jaya, Indonesia rests Freeport's Indonesian copper mining operation. Shortly after start up of Freeport's copper concentrator in 1972, lower than estimated throughput was experienced within the crushing circuit. Within one year, Freeport had successfully engineered a solution, and was operating a 5,500 dmtpd wet screening circuit. Today, after 19 years of successful wet screening expansion and operation, the concentrator processes 57,000 dmtpd.

Jan 1, 1993