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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

When a thin film of volatile matter is deposited under vacuum on a polished coal surface, and the coated surface is examined microscopically in plane-polarized reflected light, colour changes are observed which are characteristic of the various macerals present. The colour changes appear to be mainly due to interference between light reflected at the upper surface of the film and at the film!coal interface. A variety of source materials for the volatile matter required have been tested, including powdered bituminous coal, coal tars, boron oxide, and certain resins. Bituminous coal gave the best results.

Jan 1, 1970

By Susanne Hering, Brent Kirby, Charles D. Litton, Tracy Allen, Kirk R. Smith, Rufus Edwards

In developing countries, high levels of particle pollution from the use of coal and biomass fuels for household cooking and heating are a major cause of ill health and premature mortality. The cost and complexity of existing monitoring equipment, combined with the need to sample many locations, make routine quantification of household particle pollution levels difficult. Recent advances in technology, however, have enabled the development of a small, portable, data-logging particle monitor modified from commercial smoke alarm technology that can meet the needs of surveys in the developing world at reasonable cost. Laboratory comparisons of a prototype particle monitor developed at the University of California at Berkeley (UCB) with gravimetric filters, a tapered element oscillating microbalance, and a TSI DustTrak to quantify the UCB particle monitor response as a function of both concentration and particle size and to examine sensor response in relation to changes in temperature, relative humidity, and elevation are presented here. UCB particle monitors showed good linearity in response to different concentrations of laboratory-generated oleic acid aerosols with a coarse (mass median diameter, 2.1 µm) and fine (mass median diameter, 0.27-0.42 µm) size distributions (average r2 = 0.997 ± 0.005). The photoelectric and ionization chamber showed a wide range of responses based on particle size and, thus, require calibration with the aerosol of interest. The ionization chamber was five times more sensitive to fine rather than coarse particles, whereas the photoelectric chamber was five times more sensitive to coarse than fine. The ratio of the response between the two sensors has the potential for mass calibration of individual data points based on estimated parameters of the size distribution. The results demonstrate the significant potential of this monitor, which will facilitate the evaluation of interventions (improved fuels, stoves, and ventilation) on indoor air pollution levels and research on the impacts of indoor particle levels on health in developing countries.

By N. Sutcliffe

Refractories and slags play a vital role in the production of stainless steel. They are in intimate contact with the steel at temperature, and chemical reactions between the three can and do occur. These interactions can be beneficial, in the case of active tundish and ladle slags, and negative in the case of refractory erosion and slag entrapment. This paper presents the results of both plant trials and laboratory investigations of steel/refractory and slag/refractory interactions. The interaction mechanisms observed are described leading to selection criteria for new refractory products. Keywords: slags, steels, refractories, reaction mechanisms.

Jan 1, 2004

This paper is a collection of thoughts and frameworks. It addresses a simple question: æIf we are to believe the large number of people and institutions indicating that humans are destroying the Earth and that the end is nigh, why do we bother trying to be sustainable?Æ The paper lays out evidence for the existence of multiple hazards to global society. The existence of a hazard alone is insufficient to make an assessment of risk. Risk estimates are required to support decision-making. An approach to assessing risk is provided and some limited data are presented. A new ædefinitionÆ or statement of what sustainability (in a broad sense) might have become is then given. A decision framework for guiding decision- making about the risks is developed. This framework includes a definition of leadership with inherent implications for what determines whether a leadership position by title is actually leading. The paper concludes by offering a view of minerals industry sustainability and considerations around maturity in the current economic situation. It is hoped that by placing this collection of frameworks around sustainability, a supporting structure emerges that will facilitate action. It is proposed that action taken in this way will be more effective than reaction to regulation or even social license to operate imperatives because it is driven by a more holistic view of the challenges and the potential roles of individuals û all of whom are potential leaders at some scale of action.

Jan 1, 2009

By Richard D. Short

The Pseudo Static Pile Load Test, PLT, is a rapid method for determining pile capacity. Pile design is usually based on theoretical calculations of ultimate load capacity using soil data from a field investigation. The pile capacity is confirmed during construction by analysis of blow counts using dynamic formulae, dynamic pile monitoring, and load testing. Load testing is the most direct and reliable method of determining the actual capacity of a pile. Conventional load testing procedures, however, are time consuming and expensive. A typical load test requires installation of two to four reaction piles, construction of a high-capacity steel test frame, hydraulic jacks, and dial gauges, and will typically take one to three days per pile. Costs for load tests range from $10,000 to $20,000 per test. The Pile Load Test machine features a 25-tonne weight mounted on a mobile test frame. PLT load tests can be performed in a matter of minutes once the equipment has been mobilized to the site. This paper examines three test sites where the PLT test method was used and compares the results to conventional load test results and theoretical capacity calculations.

Jan 1, 2000

The Round Hill gold-scheelite deposit is located three kilometres from Macraes Flat and approximately 60 kilometres due north of Dunedin, New Zealand. A mining feasibility study is currently being undertaken on the deposit by BHP Minerals (New Zealand) Limited, who are the managers and operators of a Joint Venture with Home Reef Mining Limited. BHP has a 70 per cent equity in the project area.

Jan 1, 1987

By S. H. Ward

Since the advent of the first airborne electromagnetic system, it has been evident that such systems were inherently limited to shallow depths of exploration of the orderof 100 to 200 feet. Hence in 1948 the author and his associates commenced a study of the feasibility of applying natural audio frequency magnetic fields to investigation of the electrical properties of the subsurface in order to provide a system capable of overcoming this limitation. This research culminated, in the summer of 1958, in the development of a new airborne prospecting device — AFMAG. This device has detected surface massive sulphide bodies while flown at heights as great as 3000 feet. Hence, by inference, it is deduced that it could find similar sulphide bodies if they were buried 2500 feet below surface and the aircraft flown at 500 feet. Thus a considerable improvement over conventional airborne electro-magnetic systems is obtainable with AFMAG. Airborne exploration in mountainous terrain involving deep valley fill now becomes possible. Examples are presented of the results of actual airborne AFMAG test surveys over known deposits of massive sulphide mineralization. Interpretation of the data is discussed with particular reference to the knowledge of size, dip, depth, depth extent, and conductivity of causative bodies as deduced from the flight records. The possibility of mapping major geologic structures, for both mining and oil exploration purposes, is discussed with the aid of examples of airborne AFMAG data. INTRODUCTION Electrical prospecting with natural audio frequency electromagnetic waves as a source has, within the last three years, become a practical reality. Both airborne and ground survey instruments under the trademark "AFMAG" (for audio frequency magnetics) have been used successfully in the search for conductive mineral deposits. It is the object of this paper to discuss the principles of airborne AFMAG and to illustrate its application by means of examples obtained over known geological situations. WHY AFMAG? In view of the large number of good airborne electromagnetic systems available for purchase or contract surveying, one may well ask, "Why another new system?". Primarily the answer lies in the fact that AFMAG does not suffer from the very limited depth of exploration available with, and inherent in, any conventional airborne electromagnetic system. AFMAG is not conventional insofar as an artificial transmitter is not required. Only a receiving and detecting device is employed. The electromagnetic fields measured are those from millions of electrical discharges in the atmosphere (e.g;..- lightning strokes). Their random distribution in time and space make these fields difficult to employ and it is only with recent advances in the electronics of geophysical instrumentation that this has become possible. A second reason for AFMAG and one of its

Jan 1, 1961

By W. J. Kroll

Jan 1, 1960

By Jean-Pierre Hamelin

Ground movements induced by underground excavation are always of critical concern, particularly in urban areas. Compensation grouting now appears as a safe means to control these movements. The paper presents new advanced systems developed by the specialist contractor to bring, at all stages of the project, an efficient control of operations and presents a case history taken from the project at Tren Urbano, Rio Piedras Section, constructed beneath an historic commercial section of San Juan de Puerto Rico.

Jan 1, 2000

By Ernest M. Spokes

For bituminous and lignite coals the economic picture continued to improve as it has each year since the low of 1961, with production at 480 mil- lion tons in 1964 compared with 1963's 459 million tons. The anthracite industry produced 16.3 million tons in 1964 and 18.3 million tons in 1963. The industry is looking toward a further expansion; among the new developments will be a mining wheel producing 3 million tons of lignite per year in South Dakota. It is expected that electric power generation will continue to provide the market for most of the increase in consumption, with exports second in importance in the expansion. Improvements in methods of mining and transporting coal underground and in strip mines, and the cooperation of carriers in finding ways to reduce transportation costs to distant markets, have made possible these expansions. Research continues to reduce costs of mining, transportation, steam generation of electric power and production of steam for space heating and manufacturing processes, to retain some markets and expand others. Other research seeks to expand markets by developing fuel from coal which will be more attractive than competing fuels, by reducing sulfur and other sources of air pollution. Public relations efforts of the industry are bearing fruit in a greater acceptance of coal as a modern fuel.

Jan 2, 1965

By K. Galovich, P. Krivokuca

"Quinsam coal mine is located about 25 km west of Campbell River on the east coast of Vancouver Island, British Columbia. Using continuous miners in a fully mechanized retreat room-and-pillar operation, it produces low sulphur, “super compliance” thermal coal for domestic and international markets at a rate of about 2600 t/d. Currently, 65 people work at the site, including some corporate employees.Opened in 1993, the Quinsam mine had a dismal safety record until 1997. Lost time injuries and medical aids were unacceptably high. In 1998, a change in corporate structure brought a change in safety attitudes; a total and unequivocal commitment to safety as job No.1 by corporate and site management. This commitment was clearly spelled out in a new mission statement, circulated to all employees by the new President and CEO, David Slater: “Safety is job No. 1; Production flows from safety; and Think safety at all times.” As well as re-defining workplace safety practices, QCC tightened engineering controls and enforced strict adherence to mine plans.This paper provides a general background to the mining operation, and describes the safety practices that have resulted in an enviable safety record in recent years, reflected by provincial and national recognition."

Jan 1, 2004

By Worner H. K

Education has always been a topic to rouse the interest of mining and metallurgical engineers, but the recent activities of the Education Committee of the Australasian Institute of Mining and Metallurgy 1, 2, together with the moves throughout the Commonwealth to extend the field of technological education, have made the subject a very live one at the present time. The authors have felt it would be appropriate that on the occasion of the First Ordinary Meeting for 1950, in Victoria, some contribution should be forthcoming concerning the history, present status and possible future trends of mining and metallurgical education in this State. As for the past, the time approaches when there will be none having personal recollections of the beginning of Victorian mining schools or of the men who started them. As for the future, it is obvious that rapidly expanding metal-producing and metalconsuming industries will demand a greater output of competent graduates and diplomates. The era immediately ahead seems to be bristling with opportunities, but mining educators need to temper their enthusiasm for various policies and programmes with the realisation that they are helping to train men who will be leaders 15-20 years hence when the problems of industry and trials of life generally may be very different from what they are to-day.

Jan 1, 1950

By Andy Schroeder

Located in Hamilton, Ontario Canada, Berminghammer Foundation Equipment, is a manufacturer of advanced foundation equipment with 30 years of experience. The company is represented in more than 20 countries world wide, maintains an extensive Research and Development team, and has earned a reputation for finding the most practical solutions to the most challenging projects. The vertical travel lead, referred to as "VTL" system, was first developed and patented by C.W. Bermingham in the 1970's. This lead system was developed in response to the fundamental limitations of either a fixed lead or hanging lead system. The fixed lead system is well suited to level job sites with few obstructions and has the advantage of faster positioning of the lead, the hanging lead is very adaptable to different elevations and batter piles but takes much longer to position. Therefore the Vertical Travel Lead was developed to combine the advantages of fixed leads, fast and accurate positioning, with the ability to adjust the height of the lead base up or down. The VTL lead is connected to the boom by a sliding connection which allows the lead to be elevated or lowered below grade. The advantages of the VTL system were recognized by many foundation specialists and they have become the Industry standard in Canada , US Railway Construction , and many parts of the USA.

Jan 1, 1997

By G. de B. van Niekerk

This paper briefly outlines some mining technology that is used with success in Australia but is not yet fully utilized in South Africa. The following aspects are discussed: improved rotary-drill bit performance, use of trucks and load haul- dump units underground, long-hole raising, blasting techniques, and the use of butterfly roofbolt plates for support.

Jan 1, 1989

By Allison

During the 1980’s, laboratories opened throughout the United States to serve the analysis needs of a rapidly growing asbestos abatement industry. The samples analyzed were either collected during the abatement of known asbestos-containing materials or were suspect asbestos-containing construction materials. Many asbestos analysts received minimal training and used analytical protocols that were industry specific. False positives (reporting a sample as containing asbestos when none is present) went unnoticed or had minor repercussions. The mindset of the industry was to err on the conservative side – it would be better to identify a non-asbestos fiber as asbestos than visa versa. With growing public awareness of the health hazards of asbestos, other materials began to be tested for asbestos content. Rock and ores began to be tested for naturally occurring asbestos by these laboratories using the same protocols or an in-house protocol. Analysts were given no additional training and accreditation, in most cases, it was not required. With no consistency in sample collection, testing protocol or expertise in analysis, significant discrepancies in final results can be expected. If we further complicate this scenario with misidentification of naturally occurring look-a-likes for asbestos, expensive false positives are likely. To avoid the repercussions of misidentification of naturally occurring chrysotile asbestos from look-a-like fibers in rock and ores, correct sampling and analysis protocols with more stringent scientific diagnostic criteria are needed.

Jan 1, 2005

By Don K. Smith

The Reclamation Program for the Northern Zone of the Indus Plains in West Pakistan involves the construction of 30,000 irrigation wells to serve 20 million acres with an annual pumpage of nearly 40 million acre-ft. Detailed hydrologic studies indicated that mild steel would be satisfactory for casing; however, within two years after construction, about 10% of the wells began to fail due to encrustation and corrosion of the casing. A search to find a noncor-rosive substitute for the steel casing disclosed that only fiberglass-reinforced plastic pipe satisfied all requirements. The results of initial use of fiberglass have been highly satisfactory and have resulted in a lower over-all well cost. Advances in technology pomise further reduction in prices and improvement in performance. The northern zone of the Indus Basin comprises a vast area of essentially level land in West Pakistan which is irrigated by means of a complex system of canals that distribute more water to more land than any other irrigation system in the world. In spite of the development of this extensive irrigation system, production of food and fiber has not met the requirements of the country. The major reasons that crop production has not reached anticipated levels are the lack of adequate irrigation supplies and effective subsurface drainage. As a result, yields per acre are among the lowest in the world for areas where irrigation is practiced, and many thousands of acres of valuable crop land have been removed from production or seriously affected by salinity and waterlogging. To rectify the problems of irrigation supply and drainage the Government of Pakistan has undertaken a program of Salinity Control and Reclamation which is being administered by the Water and Power Development Authority. The Authority retained Tipton and Kalmbach, Inc., of Denver, Colo., as engineers for the program in the northern zone of the Indus Basin. This program consists of the construction of about 30,000 irrigation wells to provide drainage for waterlogged lands and full irrigation supplies, including leaching requirements, for all cultivated lands. The program will ultimately ensure the productivity of 20 million acres and involve an annual pumpage from groundwater storage of nearly 40 million acre-ft of

Jan 1, 1970

By Gabriel S. Esterhuizen

A survey of pillar conditions was carried out at 21 operating limestone mines that use the room-and-pillar method. The surveyed pillars were all located in rock that was classified as ?Good? to ?Very Good? using the RMR rock mass classification system. The average pillar width was 14.5m and the width to height ratio varied between 0.53 and 3.52. Pillar conditions were rated using a visual rating system that accounts for the effect of geological structures as well as stress related fracturing. Nine cases of pillar instability were recorded. Pillar instabilities were typically limited to individual pillars or small groups of pillars within an otherwise stable layout. Local geological structures such as inclined discontinuities or weak bedding planes contributed to instability in seven of nine cases that were observed. Elevated pillar stresses contributed to instability in the two remaining cases. All the unstable pillars observed had width-to-height ratios of less than 1.5. It is concluded that pillar instability is most likely to be caused by unfavorable geological structures in pillars with width to height ratios of less than 1.5. Stress related instability such as rib spalling becomes more prevalent when the average pillar stress approaches approximately 20 MPa.

Jan 1, 2006

By Sparrow G. J

The effect of polyelectrolyte flocculants on the de-watering of a tailing suspension of very fine clay was investigated.Sedimentation and filtration experiments were carried out in the labqratory to characterise the de-watering properties of the tailing. The results were used to calculate the effect of flocculant additions on the drainage and vaporation components of the de-watering of a clay suspension ponded on to a sand drainage bed.A flocculant increased the drainage rate, but decreased the volume of water that could be removed by drainage leaving more water to be lost by evaporation.The sorptivity values measured in the laboratory were used in the de-watering equation previously established for the tailing to estimate the effect of flocculant additions on the time required to de-water the suspension from 18.2 to 60 per cent solids w/w. The calculated de-watering times were found to increase or decrease depending on the volume of water removed by drainage and the prevailing evaporation rate.

Jan 1, 1980

By K Kongolo, M K. Kalenga

It is well known that the electrochemical precipitation of metals from aqueous solutions is conducted by the electrochemical standard potential scale. This scale indicates the order of nobility of different metals. Consequently, the standard potential scale shows the nocivity of metals when they are present as impurities in aqueous solutions containing metals. In the hydrometallurgy of cobalt, nickel and zinc are co-deposited during cobalt electrodeposition. Nickel has almost the same chemical, physical and electrochemical properties as cobalt. Furthermore, the electrochemical potential of nickel is relatively higher than that of cobalt. For this reason nickel is preferentially reduced at the cathode in the presence of cobalt. The presence of small amounts of zinc in solution leads to contamination of cobalt electro won. In spite of its lower electrochemical potential in comparison to cobalt, zinc is reduced on the cathode because of its higher hydrogen-overvoltage. But, in the hydrometallurgy of zinc, small amounts of cobalt present into solution will contaminates the zinc reduced at the cathode. This is easily explained by the fact that cobalt is more electropositive than zinc. The co-deposition mechanism of sulphur at the cathode is not yet well understood. Great attention has to be paid to the mechanism of co-deposition of sulphur during cobalt electrolysis..This work aimed to investigate the influence of some parameters on the co-deposition of nickel, zinc and sulphur during cobalt electrowinning. The following parameters have been investigated : Co2+ concentration in the electrolyte, current density and ammonium sulphate (NH4)2SO4 additions. It has been established that important nickel, zinc and sulphur co-deposition takes place at relatively low Co2+ concentration in solution. The behaviour of these elements with regard to the cathodic phenomena has been established.

Jan 1, 2005