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By Peter Fullagar, Adel Vatandoost, Steve Walters, Toni Kojovic

"Traditional comminution tests are a vital component in every mine plant design. Comminution behavior governs both the cost of equipment and its operating efficiency. Most comminution tests are conducted off site on a limited number of samples, owing to the high costs and long lead times involved. Therefore a strong incentive exists to find alternative means for efficiently characterizing comminution behavior for a truly representative suite of samples. The potential for inferring comminution behavior from drill core is investigated in this paper. Our approach involves development of small scale comminution tests on the one hand, and measurement of a wide range of core attributes on the other. Our focus is the relationship between petrophysical properties and comminution behavior.Petrophysical properties of archival diamond drill core from the Ernest Henry Mine (Queensland, Australia) have been measured using a Geotek multi-sensor petrophysical core logger. We have investigated the relationship between the petrophysical properties and the corresponding small scale A*b and estimated Bond mill work index test results for 2m composites of the core. Core samples were petrophysically classified by means of cluster analysis. Comminution behaviour was then modeled for each cluster via multiple regression. The results suggest that prediction of the comminution behavior on the basis of petrophysics is viable at Ernest Henry.INTRODUCTIONMineral processing is the most important downstream operation for mining engineers and metallurgists since most mined materials are subjected to some type of comminution or beneficiation operation (SME, 1992). Comminution or size reduction is typically the first stage of processing. Size reduction steps (crushing and grinding) in any plant consume large amounts of energy, normally more than 50% of total energy (Weiss, 1985). Therefore, it is desirable to obtain laboratory results to design the size reduction equipment appropriately. One of the main factors that control the selection of hard-rock crushing equipment and the design of a crushing circuit is the mechanical character of the ore(s). Work index, density, abrasivity, compressive strength and clay content are essential parameters for ore characterisation (SME, 1992)."

Jan 1, 2009

By Carmel Bofinger, Maureen E. Hassall, David Cliff, Eric Stemn

e Springer Nature remains neutral with regard to jurisdictional claims in published maps and institutional affiliations.

By Carmel Bofinger, Maureen E. Hassall, David Cliff, Eric Stemn

e Springer Nature remains neutral with regard to jurisdictional claims in published maps and institutional affiliations.

By Les Johnston

_ BACKGROUND - About EPCOR - Genesee Generating Station - Phase 3 Expansion _ TECHNOLOGY SELECTION - Selection Criteria - Combustion Options - Flue Gas Emission Control Options _ STAKEHOLDER VIEWS _ PROJECT STATUS _ EPCOR is an integrated utility company for water, gas, electricity and technology services. _ EPCOR has about 1.6 million customers in Alberta, Ontario, Manitoba, BC, and the U.S. Pacific Northwest. _ EPCOR Generation Inc. operates three power stations in Alberta which were in operation before deregulation, including the coal-fired Genesee Generating Station. _ EPCOR Power Development Corporation owns generating stations in Alberta, BC and Washington State and will be building the Genesee Phase 3 expansion.

May 1, 2002

By William Reisz

Over the years as surface mining operations have become more sophisticated, angle drilling has become a more popular blast design technique, especially in areas where overburden and stripping ratios have increased. Another method of blast design is the staggered pattern, which greatly improves explosives distribution within the blast. While both methods present some engineering challenges, this paper will discuss how the two methods can be combined to enhance fragmentation, improve cast percentage, drill production ratios and highwall control. A practical engineering approach will be presented as well as a discussion on the discipline required to maintain a quality blasting plan.

Jan 1, 2002

By William G. Hedling

The operation of electric face equipment in underground coal mines has proven to be extremely hazardous to mining personnel, including equipment operators and others working in the vicinity of active equipment. Recent industrial engineering studies* of accidents and fatalities indicate that a major contributor to this hazardous situation is noncompliance with modern principles of human engineering, particularly lack of standardization of control configurations. Control configurations differ not only among different machine types, but also among the same machine types produced by different manufacturers. This lack of standardization can produce a high incidence of error in the operation of electric face equipment, thus creating a potential source of accidents. Other examples of non-compliance with human engineering principles are the widespread use of identical black, round control knobs (regardless of the function being performed), and the inappropriate location, spacing, and labeling of controls. Any or all of these factors may place the operator in a "negative transfer" situation, which means that control manipulations appropriate for one type of machine are different from (or even the reverse of) the control movements required to produce the same effect on other machine types. This situation increases the accident potential to the operator, as well as to others in the vicinity. Accident potential is further increased by circumstances which do not allow for large error tolerance-specifically, emergency procedures. Reports of accident statistics cite operator inexperience as a primary cause of most accidents involving underground electric face equipment. Several factors contribute to operator inexperience, including: 1. High personnel turnover 2. Employee absenteeism 3. Current union practice of bidding for jobs.

Jan 1, 1974

By J. C. Thornley

Service failures of seemingly conventional galvanized bolts, in normal operation, on transmission towers in New Brunswick have been found to be the result of hydrogen cracking. In both these cases, similar failures elsewhere can be avoided by suitable clauses in the purchase specifications. In the first case described, the manufacturing procedure was responsible for strengthening and embrittling a standard, soft, constructional steel. In this case, a fracture mechanics analysis predicted critical crack depths for final fracture very similar to those found in practice. This case reveals an apparent cooperative connection between hydrogen embrittlement and strain ageing in plain carbon steels. In the second case described, the steel was simply a high strength steel which should not have been made into galvanized bolts.

Jan 1, 1979

This paper discusses the social and economic impact of mining, and in particular goldmining, on New Zealand. The range of topics covered and their complexity has confined us in this paper to highlighting the main points of concern û a detailed report is under preparation. A major problem in undertaking this study was the lack of hard data on important environmental, economic and social issues and if there is to be effective planning in the area of natural resource use this situation must be rectified. The following conclusions were drawn: Goldmining was very important in shaping New Zealand's early social and economic development, providing wealth, employment and impetus for social change.Foreign investment and technology has been an essential element in New ZealandÆs economic development.Mining is a small industry at present by this must not be allowed to obscure its potential to broaden New Zealand's economic base and provide foreign exchange.With modern methods, development of mineral resources and environmental protection are not incompatible but certain unique and irreplaceable areas must be preserved.There are problems in evaluating mining and other projects because different groups hold different values, and arguments often hinge on the valuation of costs and benefits rather than the technical aspects of the analysis.Mineral exploration is a high risk business and the potential returns must be sufficient to attract capital if New Zealand's mineral resources are to be developed.A resurgence of goldmining will clearly have obvious benefits for Waihi but the local community must plan carefully for their future. New Zealand will also gain valuable foreign exchange required for higher levels of economic activity.

Jan 1, 1981

By C. A. Johnson, K. F. Unrug

The identification of the major subsidence areas in the Eastern Kentucky Coal Field has been made to distinguish the subsidence phenomena on the basis of geographical location. Further, this identification process is based upon selected critical geological, topographical, and mining features in the coal fields. The proposed identification of the regions is derived from a comparison of the subsidence potential in a particular area. The most likely severe subsidence areas are compared to those with the probable low subsidence severity. The combination of certain geological and mining parameters involved allows for the derivation of a classification of the subsidence potential.

Jan 1, 1986

By Arcy, D&apos Banister

The productive potential of the Nation's principal active and inactive silver mining districts has been evaluated, using 1964 economic conditions and assumed silver prices ranging up to $3 per ounce. On this basis, the United States has an estimated 5 billion ounces of unmined silver, excluding minor byproduct silver in gold deposits. Approximately 3.5 billion ounces are contained in deposits requiring higher silver prices to be economically minable, and about 1.3 billion ounces are in currently operating mines. An analysis of silver consumption trends since 1954 indicates that the free world industrial market will climb to nearly 800 million ounces annually by 1985. U.S. industrial silver consumption has been projected to increase at an annual rate of 4 percent from 1965 to 1985. Average annual increase for the remainder of the free world has been 8.1 percent since 1953; this is expected to level off with an estimated average increase of 5 percent to 1975 and 4 percent from 1976 to 1985. Foreign silver production has, in the past, exceeded consumption, but in 1960 the supply deficit was over 100 million ounces. U.S. production, also traditionally exceeding demand, was suddenly overtaken at the start of World War II. By 1964 the annual deficit, excluding coinage, was over 84 million ounces. World coinage requirements of silver are fast declining and expected to total only 25 million ounces annually by 1985. In fact, coins are already becoming major short-term source of silver to fill the large deficit between industrial demand and current production. The larger, long-term deficit (to 1985, the limit of this study) must be balanced by silver from the hoards and new production from silver deposits. Eventually all of the deficit must be met by new production or silver prices will rise until consumption is greatly curtailed. To balance free world supply and demand, it is estimated that the free world must produce an additional 85 million ounces by 1975 and 375 million ounces by 1985. The estimated proportion expected from U.S. deposits is 17 million ounces by 1975 and 74 million ounces by 1985.

Jan 1, 1969

By Z. Zhang, M. S. Gonzalez, M. de P. Bueno, P. Holopainen, S. Luukkanen

"Despite being a field of study that requires practical knowledge and experience, mining engineering education follows the same pattern in most mining universities around the world, consisting of theoretical courses and laboratory-based practical modules (Mischo, 2015). The possibility of having practical training in real mining conditions on actual mine sites or processing plants is limited, while the only contact that undergraduate students have with mining operations during their time of study is usually through shorttime internships or visits in the context of educational trips. Real integration between universities and the mining industry may be scarce, which does not help students to observe the actual processes and thus understand the whole picture of mining operations.Indirect practical training is now possible since that technology is shifting from mechanical to digital, and the use of virtual reality — in the context of Mining 4.0 — can provide additional experience to the learning process. However, virtual reality is limited to the visual impression and is also limited in actions (Binder et al., 2018). In any case, when there is not a proper pragmatic view of how the different disciplines link to each other, especially if there is a lack of communication, unfortunately the results could be seen at a later stage in the mines as a poor performance of professionals and workers.Another major challenge for educating specialists in the mining sector is that experimental mines suitable for practical education, where the skills and knowhow could be developed and/or enhanced, are rare worldwide. Such research and educational (R&E) facilities are practically former metal ore mines that have been transformed into experimental sites. Besides being limited in number, not all facilities of this kind serve both a research and educational purpose.An early example of asolely experimental mines is the Luossavaara-Kiirunavaara Mine site operated by LKAB in Sweden, where systematic research on rock mechanics and mining engineering was successfully carried out in the 1980s. As a result, the developed underground mining technology was applied in LKAB’s mines at a later stage. There have also been research mines within collieries such as the former Lake Macquarie Mine at New South Wales in Australia and the Zeche Tremonia Mine in Germany), but these are no longer in operation (Mischo, 2015)."

Oct 1, 2019

By Paul Voigt, Mike Hourn, Glenn Stieper

Sable Zinc Kabwe Limited ("Sable") is a base metal processing plant, two kilometres south of Kabwe Town in Central Province, Zambia. The region has a rich history in mining and minerals production, being a major lead and zinc producer from the 1900s up to the mid-1990s. In 2006, a copper plant was built at the Sable processing site to treat third-party copper and cobalt oxide ores and concentrates. The oxide leaching plant included whole ore leaching, solvent extraction and production of 8,000 tpa LME Grade A copper cathode. The plant was placed on care and maintenance in 2014, and Glencore Plc ("Glencore") took the opportunity to convert the plant using a minimal budget, to an Albion Process™ plant to treat local refractory copper concentrates unsuitable or uneconomic for smelting. The Albion Process™ plant comprises an M100 IsaMill™ operating in acidic conditions such that raffinate from the downstream process is recycled back to slurry the concentrate delivered to site thus maximising copper tenor in solution and reducing water consumption. The finely ground concentrate feeds an oxidative leaching plant using the existing stainless steel oxide leach reactors converted to Albion Process™ duty by fitting HyperSparge™ supersonic oxygen injectors and gas dispersing agitators. The leached slurry is then directed to the existing solid/liquid separation equipment, and the PLS is then sent to the existing SX/EW plant. The plant also allows for cobalt recovery from the raffinate. The plant was designed based on testwork on regional copper concentrates. The plant was designed to toll treat a range of concentrates, and so the design was flexible With the flexibility of the Albion Process™ being one of its distinct advantages, the plant was ideally suited for tolling regional concentrates. The plant was commissioned and ramped up in six weeks using low-grade Zambian copper concentrate, and produced exclusively LME Grade A copper with over 99% leach recovery in the Albion circuit. INTRODUCTION The Sable Zinc Kabwe Limited ("Sable") process plant is located 2 km south of Kabwe town and 140km north of Lusaka in Central Province, Zambia. In 1902, rich deposits of zinc and lead were discovered with mines and processing plants operating in and around the town until mid-1994. In 2000, the Kabwe Mine tailings dams were sold to Sable, a newly established company, as part of a purchase deal for other plots and facilities. Up until 2004, Sable produced zinc cathodes in an SX/EW plant treating wash plant tailing material. In 2004, Sable was acquired by the South African mining company Metorex Limited ("Metorex"), and in 2006 a copper/cobalt SX/EW plant was built to produce copper cathode from malachite ore supplied from the Democratic Republic of Congo. In 2011, Jinchuan Group International Resources Co. Ltd acquired Metorex and Sable was in turn sold to a subsidiary of Glencore Plc ("Glencore").

Jan 1, 2019

By NORMAN EBBLEY

NUMEROUS references have been made recently to "Alaska's oil reserves," and in view of the wartime petroleum situation sober thinking demands a dispassionate and scientific study and investigation of these reserves or supposed reserves. The question naturally arises, "Is there actually oil in Alaska, or are the reserves there a supposition?" True, in 1923 President Harding established Naval Petroleum Reserve No. 4 in Alaska, certainly implying that oil was there. This reserve, embracing about 35,000 sq. mi., was set aside on the advice of the Bureau of Engineering of the Navy Department and was based upon the existence of known petroleum seepages at Cape Simpson on the Arctic coast. The Cape Simpson seepages have been known for more than fifty years, but in spite of persistent rumors of other seepages in northern Alaska no definite evidence of their existence has been available.

Jan 1, 1944

By A. Nuric, S. Nuric, L. Kricak, M. Negovanovic, S. Mitrovic

"SynopsisRotary drilling with rolling tricone bits is the most widely used method for drilling large-diameter blast-holes in large surface mining operations. This drilling method is applicable to a wide range of soft to hard rock materials. This paper presents a fuzzy model for predicting the penetration rate of tricone rotary blast-hole drilling. The model is based on data obtained during the drilling of blastholes in rocks with various uniaxial compressive strengths in the Veliki Krivelj open pit mine, Bor, Serbia. The model was developed using the fuzzy logic toolbox of MATLAB with the Mamdani inference system. The fuzzy model was tested with 23% of the total dataset. The results obtained show the high reliability of predicting the penetration rates. Although there are possible limitations in applying the model to other open pit mines because of differences in rock properties, the prediction methodology applied in this paper can be used in many other predictions of the penetration rates.IntroductionAccording to Tamrock, rotary blast-hole drill operations depend on four important elements:•,Torque in the drill string drive sufficient to turn the bit in any strata encountered•,A high bit loading capability (pulldown force) sufficient for optimum penetration•,An air volume sufficient to remove chips generated during the drilling and to provide cool air to the drill bit bearings•,The selection of the proper type of bit for the material being drilled (Tamrock, 1984).The effects of rock mass parameters on the choice of the type of tricone bits were investigated by Kricak (1997)."

Jan 1, 2015

By Adrian Daniel

"Dating back to 1934, Con Mine is located directly south to the city of Yellowknife in the NWT, Canada. With mill operations ceasing in 2004, a challenging surface remediation situation resulted which required the treatment of close to 40,000 m3 of Arsenic impacted material.Through much of the period of 1941 to 1970, Con Mine treated their refractory arsenopyrite ore through the use of an Edwards Heath roaster. With mounting environmental pressure and through Canadian governmental studies during 1950 to 1970, attention was directed to the Arsenic Trioxide material being collected by two Doyle scrubbers on the Con’s roaster stack. In 1970, the roaster was decommissioned leaving the resulting Arsenic material in two containment areas on surface.As a result of Con Mine entering into remediation in 2004, the Con’s autoclave, commissioned in 1992, was dedicated to the immobilization of high impacted Arsenic material through the combination of excess Iron under high temperature and oxygen overpressure. Examined, herein, is the history and chemistry of the Con Mine autoclave as well as the two stages of chemistry for the Water Treatment Plant used to remove arsenic, heavy metals and WAD cyanide from tailings water. Simplified capping plans of the tailing containment areas and a high arsenic impacted area are also presented.INTRODUCTION TO CON MINECon Mine (Con) is situated just south of the City of Yellowknife in the North West Territories (NWT) Canada and is bounded locally by Yellowknife Bay (North Extension of Great Slave Lake) to the east and Kam Lake to the west (Figure 6). The discovery of gold at Con was made in 1934 and mineral rights were acquired by Consolidated Mining and Smelting Limited (Cominco) and Falconbridge soon thereafter. Nerco Minerals Limited (Nerco) took control in 1986 and in 1993, was subsequently sold to, Miramar Mining Corporation which in turn was purchased by friendly takeover involving Newmont Mining in November 2007 as a result of acquiring the Miramar’s Hope Bay project. Con’s underground operations ceased in September 2003 and have since entered into the remediation of the site. The current surface lease holdings are about 340 Hectares (Table 1) which sits on top of the Archean-aged Yellowknife Greenstone Belt."

Jan 1, 2009

By J. P. Powell

The increased costs of exploration and drilling of new oil fields and the continued success of water flooding in nearly depleted oil fields have created a demand for information on the results obtained from individual projects. The Bureau of Mines has published several reports concerning water-flood activity in the Mid continent area and at the request of the industry has continued to collect and disseminate this information. This report was written in response to these requests. It describes in detail the water-flooding projects in Anderson, Franklin, Linn, and Miami Counties, Kans., and includes methods of water treating and the results obtained. The production histories of each county and many water-flood projects are shown graphically from the date of the first development. Maps of most of the major projects, showing their status as of January 1, 1953 are presented also. The practice of injecting water to stimulate oil production was legalized in Kansas in 1935, and the first water-flooding project authorized in this four-county area was initiated by the Texas Co. in December 1935 in Linn County, Forty-nine projects2/ initiated in the area to January 1953 are estimated to have recovered approximately 10 million barrels of oil that could not have been produced by methods used previously. About 7,900 productive acres had been, or are, flooded by these projects, and approximately 1.36 million barrels of water had been injected.

Jan 1, 1953

By G. E. Pearse

Reports, discussions, a written contribution and two written replies are presented from 11 sessions on: Safety and compressed air; Ground movements; Geotechnical; Channel Tunnel (2 sessions); Machines; Case histories; Transport tunnels; Case studies; Site investigation; and Undersea tunnels

Jun 13, 1905

The Ocean Drilling Program (ODP) is the largest international geoscience project in the world, and the state-of-the-art drill ship, the JOIDES Resolution, is permanently at sea. Each year there are six scientific cruises (legs) which each last approximately two months. These legs are designed by geoscientists from the nineteen countries that subscribe to ODP.Australia and Canada presently share ODP membership under the banner of the AUSCAN Consortium. The benefits of Australia's involvement in ODP include internationalisation of Australian geoscience, advanced graduate training, and unique scientific investigations of the ocean floors in the Australasian region. In addition, visits to Australian ports by the ODP drill ship, the JOIDES Resolution, contribute up to $2 million per visit to the local economy. Amongst the many other aspects of ten years of scientific drilling, OOP has significantly contributed to our understanding of hydrothermal processes on the seafloor. To date, three hydrothermal sites have been drilled to date by the OOP, Snakepit (MAR), Middle Valley (Juan de Fuca Ridge) and TAG (MAR). Two more hydrothermal sites are scheduled for 1996.

Jan 1, 1995

By Ray Walton, Ron Colquhoun, Ken Thomas, Dwayne Fentie, Barney Burke

"The new Roasting Facility at Barrick’s Goldstrike Mine in Nevada, U.S.A. was developed to process 12,000 tons per day of refractory gold ore. The process consists of crushing, dry grinding, roasting, extensive gas purification, calcine quenching and leaching in the presence of activated carbon. The new plant is integrated into the existing Goldstrike facility, treating ore from both open pit and underground sources.The process design, procurement, construction and commissioning of the Roaster facility was performed successfully over a 3% year period with peaks of 400 engineering personnel and 950 construction personnel supporting the project. The US$330,000,000 project was completed ahead of schedule and under budget. The commissioning was well planned and proceeded smoothly through a rapid start-up to achieve all primary goals within three months of the start of processing of ore.BACKGROUNDAs early as 1992, Barrick’s Goldstrike Mine, located north of Carlin, Nevada had indications of the ore becoming ever increasingly carbonaceous in nature. As the open pit and underground exploration programs proceeded to step out over the years that followed, the accumulative amount of carbonaceous refractory ore and tons had become significant. By 1997, 29 million tons of double refractory carbonaceous ore containing an estimated 11.6 million ounces of gold had been identified. By 2000 the resource had increased to 14.3 million ounces."

Jan 1, 2001

By J. M. Ortiz

This paper shows the usefulness of geostatistical conditional simulation combined with the quantification of sampling errors obtained from the analyses of fundamental errors ? validated from duplicate data ? to assess the relevance of the quality and quantity of the information, for short-term mine planning purposes. Traditional blast-hole drilling equipment has been designed for efficient drilling, but not for obtaining high-quality samples. Furthermore, blast-hole sampling interferes with production, and thus usually produces poor-quality results. These results are the basis of short-term plans, where the grades of selective mining units are estimated and used for distinguishing between ore and waste. Under these conditions, misclassification (ore blocks sent to the waste dump and waste blocks processed at the plant) is inevitable, leading to significant hidden losses that can amount to millions of dollars per annum. Reverse circulation drilling with the latest automated sampling technology improves significantly the quality of the information used for short-term planning, and thus reduces misclassification, improving the financial returns of the operation. In this paper, we present the general methodology for assessing the effect of poor blast-hole sampling, as compared to advanced reverse circulation drilling grids at several spacings, in order to arrive at the most appropriate grid for short-term planning. This plan can be prepared well in advance using several additional variables that are usually not available when the plan is based on blast-hole samples. Furthermore, blending options can be analysed in order to optimize plant recovery, minimize the use of sulphuric acid, etc. Three case studies are presented, namely a typical porphyry copper deposit, an exotic oxide copper deposit, and a complex gold deposit, where mineralization is controlled by structures and lithology. This paper shows that in all cases, advanced reverse circulation drilling grids provide good-quality information that, coupled with the use of geostatistics for short-term mine planning, significantly improve the financial returns of the operation.

Jan 1, 2014