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By A. G. Fabbri

This paper aims at the application of quantitative criteria for evaluating the mineral potential of square cells representing areas in terrains being explored at a reconnaissance level. The assumption is made here that the evaluation methods used by an expert economic geologist can be organized into geological models for establishing associations within imaged areas, that correspond to pixels with similar characteristics. UTM-registered multiple data sets have been constructed which include seasonal LANDSAT 2 and 4 images, SEASAT scenes, selected airborne radar images, digitized aeromagnetic, gravity, bedrock geology and topographic elevation maps. The area of interest is located in the Bathurst Inlet, District of MacKenzie, N.W.T., where a preliminary mineral potential evaluation was performed by the Geological Survey of Canada to assess its suitability for a national park. The multiple data sets described in this paper can be used for many studies at different resolutions, for comparing processing methods in remote sensing and, most importantly, for evaluating the physical and spatial relationships between the different images in registered data sets.

Jan 1, 1989

By F. Bonnet, J. Lehmann, H. Gaye

A review of thermodynamic information and models of slags, including associated software when available, is presented. The pertinence and accuracy of these models is discussed by comparison of their predictions for various slag thermodynamic properties with the available experimental data. Practical industrial applications will be illustrated by a literature review of the dephosphorization process of ferromanganese alloys and by the description of Ti behavior during silico-manganese alloys production. This latter example will show how the thermodynamic models have been used to propose a flotation treatment at low temperature to enhance TiC removal.

Jan 1, 2004

The Lane Cove Tunnel (LCT) is an important infrastructure link in New South Wales (NSW) and runs from the end of the Gore Hill Freeway at Artarmon at its eastern extremity, to the end of the M2 at North Ryde at its western extremity.  The LCT is 3.6 km long and generally consists of twin two/three lane unidirectional tunnels running largely under Epping Road from just east of Mowbray Road, west to the western end of the Gore Hill Freeway. The tunnel opened in early 2007. The presentation will provide a summary of the traffic and emission modelling performed for selected representative surface road sections in the vicinity of the Lane Cove Tunnel. An assessment of the predicted impact of vehicle emissions on ambient air quality in the corridor as a result of changed traffic conditions due to the tunnel opening will be presented. The traffic modelling and emission calculations were undertaken for the following two scenarios: Year 2006 û Lane Cove Tunnel no-build option, and Year 2006 û Lane Cove Tunnel build option. Vehicle emission calculations for the four main pollutants from vehicles: CO, VOC, NOx and PM10 on the surface roads in the vicinity of the Lane Cove Tunnel were performed using the predicted daily traffic for the two cases (no-build and build). The analyses indicated that the vehicle emissions for all pollutants are expected to significantly reduce in the corridor with the building of the Lane Cove Tunnel, including the areas in the vicinity of all tunnel portals, when compared to vehicle emissions for the no-build case.  As a result of the decreased vehicle emissions on the surface roads, the study concluded that the actual ambient air quality is expected to improve in the corridor including the tunnel portal areas after the Lane Cove Tunnel opening.

Jan 1, 2008

By Knevitt L. T

PART 1Details of Kiewa Scheme.Introduction.Topography.Preliminary Investigations.Geology.Description of Project.Details of Main Works.Main Transmission of Power.Construction Facilities.PART 2Underground Works.Summary of Projected Works.Administration.Labour.Surveying.Safety and Accident Prevention.Medical Attention and First Aid.PART 3No. 4 Head Race Tunnel.Summary.Geology.

Jan 1, 1950

By Robert E. Barieau

The following zero pressure thermodynamic properties of nitrogen gas are tabulated: [C°p, H° -o, S°], These properties are tabulated in units of joules, gram mole, degrees Kelvin and in calories, gram-mole, degrees Kelvin for every degree Kelvin from 50° to 550°. The same functions are also tabulated in units of British thermal units pound-mole, degrees Rankine for every degree Rankine from 100° to 1,000°.

Jan 1, 1967

By A. A. Bustos

Four Air Liquide Shrouded Injectors (ALSI ) were installed and operated for over one year in a Peirce-Smith converter at the Falconbridge nickel smelter in Falconbridge, Ontario, Canada. A shrouded injector consists of an inner pipe and an annulus, through which high oxygen enriched air and nitrogen flow, respectively The nitrogen cools the injector and protects the refractory in the vicinity of the injector tip, allowing for substantial increases in oxygen flow rates to the converting reactions. Several injector designs were tested to study the effect of changes in the cross-sectional area and changes in the entrance geometry of the annulus. An optimum design would minimize the injection pressure required for a given flow rate to achieve choked flow conditions at the tip of the injector. The operation of the ALSI was simple and did not require any special care or maintenance, either between blows or between converter cycles. In particular, the shrouded injectors did not require punching, as is the case with conventional tuyeres. In terms of refractory performance, the ALSI, operating at 30-40 % oxygen enrichment, were superior or equal to the conventional tuyeres, which operated at 21-23% oxygen. The results of the demonstration program led Falconbridge Limited to implement the ALSI technology on a commercial scale The paper presents the demonstration program results in terms of gas flow rates, accretion formation, punchless operation and refractory wear.

Jan 1, 1999

By R Adofo

Underpinning the mining process is a continuum of prediction, specifically of tonnes, grade and recovery from exploration to grade control, through short-term mine design, to mining and processing. The interdependence of one activity on the other is so strong that it can be difficult to partition the activities and determine where there are issues, if any. Reconciliation is the process that compares the predictions of the various estimates to the actual product produced at the end of the production chain. Quite often, an attempt to understand the variances from one measuring point to the other creates a ‘wicked problem’.This study outlines the benefits of incorporating the principles of ‘systems thinking’ into the mining reconciliation process, by constructing a framework within which reconciliation is effectively managed. The philosophical base for any variances between successive links in the reconciliation chain cannot be attributed purely to the statistical variance between the predicted and the actual grades achieved, but should include the interrelationships between the technical and managerial professionals involved. Systems thinking, as an interdisciplinary approach, draws its ideas and concepts from a variety of disciplines, and in so doing can exploit their different strengths.The study described in this paper offers methodologies to analyse the task, in advance of developing a technical solution. Two systems thinking methodologies, Grounded Theory (GT) and Soft Systems Methodology (SSM) were employed. These methodologies, are geared towards dealing with relationships and interactions between individual parts and the whole. The GT coding in the study specified that the key activity that would drive the reconciliation process is through an effective reconciliation meeting, and the competencies of a ‘reconciliation team member’ This team member should be a good communicator and enjoy challenges, be open-minded and transparent, and have a broad perspective of the mining process and relationships across the different activities.CITATION:Adofo, R, 2017. A systemic approach to managing the Mine to Mill reconciliation process, in Proceedings Tenth International Mining Geology Conference 2017, pp 95–102 (The Australasian Institute of Mining and Metallurgy: Melbourne).

Sep 20, 2017

By W. Scheetz

The Brewer Gold Mine is an open-pit, heap leach operation that processes about 122 kt/m (135,000 stpm). The mine is operated by Brewer Gold Inc., a subsidiary of Westmont Mining Inc., and is located near Jefferson, SC, about 80 km (50 miles) southeast of Charlotte, NC and 80 km (50 miles) northeast of Columbia, SC (Fig. 1). All of the ore to date has been produced from a breccia body of hydrothermal origin and a related smaller body of fault-controlled ore, known as the B-6. Reserves at the time the mine commenced production were 4.6 Mt (5.1 million st) grading 1.4 g/t (0.042 oz per st) gold. History Although some reports of a pre-Revolution War shaft at the Brewer are in the literature (Lieber, 1856, Nitze and Wilkens, 1897), gold was first produced in earnest from the Brewer Mine in 1828. Production occurred primarily from placer deposits south of the present mine workings. Lieber noted in 1856 that “every branch, gulch, ravine or even declivity of the main hill has been washed and rewashed.”

Jan 1, 1991

The theory and practice of sampling of particulate material have been the focus of a continued attention on the part of the mining industry worldwide for almost a century now, because of its critical importance at all phases of a mining project, from exploration (bulk sampling, assaying) to production (grade control) and marketing (quality control). A powerful, complete theory was put together by P. Oy (1968 to i982), but its applications to gold ores have met with limited success to date, due to the inadequacy of its sampling variance and minimum sample mass determination formulae to the challenging case of gold ores. This paper presents a research project completed at Inco Exploration and Technical Services Inc., using a geostatistical approach, to shed light on the results of P.Gy's theory, and adapt them to the case of particulate gold ores. After a reminder of Gy's formulae and a simplified demonstration of the generic form of Gy's and more traditional formulae, an empirical approach, based on sampling experiments from four gold deposits, shows how Gy's formulae must be corrected to adjust to the case of gold ores. The generality of the results formula is then substantiated with a geostatistical analysis of the problem. A parameterized formula results, and indications are given on how to fit its parameters to experimental data. Application guidelines and charts to fit any case and budget are presented, along with a detailed practical example.

Jan 1, 1991

Start with your assessment of the minerals business —domestic mining as well as operational and consulting perspectives. As a third generation miner, I have been living the mining business for as long as I can remember. I have watched commodity prices produce boom and bust cycles in places like Price, Utah (coal), Douglas, Arizona (copper) and Eureka, Nevada (gold). It is unsettling to see how our industry has fluctuated, but it always seems to rebound if you can stick out the down cycles. However, our most recent dip in the cycle was, in my opinion, characteristically and permanently different. In the past, when prices went south, people hunkered down and waited out the cycle until things came back, much the same as they had every other time. Not this time. This time, we saw a consolidation of the industry in proportions never seen before. Mega-mergers like Exxon-Mobil, Phelps Dodge-Cyprus and Newmont-Normandy have changed the complexion of our industry forever. And that is true not just of the mining companies; it happened across the supporting business lines as well. As a midsized niche engineering and environmental service provider to the mining industry, companies like mine are few and far between these days. The lean cycle saw many of the small and midsized providers get gobbled up by consulting giants like URS and TetraTech. The mentality of a mega-company, whether a commodity producer or a goods or service provider, is different than that of their small- and medium-sized counterparts.

Jan 1, 2005

By Marcelo Macedo Fialho

No processo produtivo de aço, as empresas buscam continuamente a redução do custo de produção. Isto pode ocorrer através de diversas formas, tendo como as principais, o ganho de rendimento, o aumento de produtividade, a redução do homem hora aplicado e a redução do custo de matéria prima. Objetivando reduzir o custo de produção integrado placa bobina, a ArcelorMittal Tubarão busca aumentar o percentual de placas enviadas diretamente do Lingotamento Contínuo de Placas para o Laminador de Tiras a Quente. Os ganhos se dão, em primeiro plano, através da redução da intervenção nas placas aumentando o rendimento de placa e exigindo menos mão de obra para o corte e escarfagem de placa e, em segundo plano, através do aumento da temperatura média de enfornamento, propiciando maior produtividade no laminador de tiras a quente e menor consumo de energia para realizar o pré-aquecimento da placa antes do processo de laminação. Somado a isto, a maior disponibilidade de placas no pátio do LTQ, aumenta a chance de laminação exigindo menos paradas do LTQ e aumentando a produção. Os ganhos estimados com o projeto, apenas no que diz respeito a redução de custo de condicionamento são de 6MUSD/ano.

Jul 30, 2018

By A. Moyano

The development of the traditional converting process performed in a PeirceSmith or Hoboken converter is limited by the investment magnitude associated to the fulfillment of the environmental regulations. Thus, the continuous converting process rather than a conceptual process alternative is becoming a necessity for a smelter facing limited converting capacity and/or lacking of fulfillment of the environmental regulation with its maximum converting capacity. The objective of this paper is to present the progress of the Codelco continuous converting process evaluated at pilot-scale level when converting solid mattes or white metal into blister copper. These tests allowed for gathering of relevant data to be considered for a new stage of evaluating the Codelco continuous converting at industrial-scale test. The pilot-scale tests were done in a Teniente Converter pilot scale unit at the Codelco Norte Smelter. The results of processing solid copper mattes (65-75% Cu) and producing low sulfur content blister copper with production of a constant S02 gas concentration, and the production of liquid slag with low copper solubility was achieved and is discussed in the present paper.

Jan 1, 2007

By M. D. Cooper

FOr the purpose of obtaining some first-hand data in regard to the shooting clown of coal in bituminous 'nines, it was the writer's good fortune to be employed as a shot-firer for almost one year. In all, 6,020 shots were fired by him during this period. All of the work was clone in what is known as the South Main section of the No. 2 Mine of the Ellsworth Collieries Co., Ellsworth, Pa., a subsidiary of the Lackawanna Steel Co. Position of Shot-firing in the Cycle of Operations The established practice of the Ellsworth Collieries Co. calls first for the undercutting of the coal by electric chain machines across the face of the entry or room. This is followed by replacing any posts removed by the machine-runners, or the setting of new posts or timber, as may be required. After this has been done the machine cuttings are loaded into cars. Then the coal is spragged, and a shot hole drilled to the depth of the undercut. Next in order, the shot-firer loads the hole and fires the charge. The working place is then cleaned up, timbered if necessary, the sides and face squared up, and loose material taken down. The face is again ready to be undercut.

Jan 1, 1917

By J E. Askew

The rapid expansion of gold production in Australia over the last five years can be attributed in part to the development of selective mining techniques for open pit gold operations. These techniques allow an increase in head grade with a substantial reduction in mill feed tonnage, as compared with traditional open pit designs. As a result, the capital requirements for mine development and mill construction are substantially reduced, improving the cash flow profile in the early years of operations. To put such a design into effect, the emphasis of mine production must be on producing gold, rather than tonnes of ore. Mine planning at Martha Hill has been based on such a philosophy. After the quantity and grade of the resource had been defined, the exploration programme was increasingly concerned with the local variability of ore zones, and with determining the position of values within broad ore-definition envelopes. The purpose of this work has been to allow the prediction of the tonnages and grades achievable from various levels of the pit when mining selectively using hydraulic excavators. The studies have so far indicated that the Martha Hill deposit can be mined selectively during the early years of production. The additional costs for detailed grade control and a reduced digging efficiency are more than compensated by the exclusion from the mill feed of much valueless material.

Jan 1, 1986

By Peter Megaw

The paper point out that the carbonate Carbonate Replacement Deposits (CRDs) are epigenetic, intrusion-related, high-temperature sulfide-dominant Pb-Zn-Ag-Cu-Au-rich deposits that typically form lenses or elongate to elongate-tabular bodies referred to as mantos or chimneys. Recent studies have shown that CRDs do occur in predictable geologic environments, allowing focusing of regional exploration. In addition, they have mappable alteration patterns that can be used to determine the magnitude of a given system and elemental zoning patterns that greatly enhance the chances of drilling success. Several recent discoveries of “blind” replacement deposits have been made by careful field evaluation of host and capping rocks coupled with geophysics.

Apr 24, 2001

By K. L. Lownie

For research and test data to serve a useful purpose, it is essential that it be derived from some known standard test procedure that allows for comparative analysis as well as independent replication and verification. Fan performance data provided by manufacturers is not absolute, and is influenced by the geometry of the test installation. For these reasons, fan test standards have been prepared in order to establish a clearly defined test procedure that allows for comparison of different fan designs, and also allows for the independent verification of test data. Internationally recognized Standards such as BS848, ISO5801, and AMCA 210 etc. are highly prescriptive, and precisely specify test duct configurations, measurement procedures, measurement planes and instrumentation to be used. Provided the laboratory tests are conducted strictly in accordance with the relevant Standard, the performance data will accurately reflect fan performance within the appropriate tolerances for efficiency, pressure and flow when tested in the defined configuration. Major differences in performance exist between a fan tested in accordance with a Fan Test Standard, and an identical fan installed in a mine ventilation system. The aerodynamic performance of any fan will be influenced by the quality of the fan manufacture, the flow system within which it is operating, the location of measurement planes, and the system stability. The flow distributions present in a standardized Laboratory test are unlikely to be repeated in mine ventilation systems, and this will also disadvantage fan performance. Unless the fan supplier takes all of these influences into account, there will an inevitable reduction in fan aerodynamic performance, and the end user will experience a shortfall in expected flow through the mine. The effect on fan performance can range from minor inconvenience to catastrophic fan failure resulting in major rectification costs and significant loss of mine production.

Jan 1, 2009

By S. J. Rodgers

This report presents the results of in-mine studies to determine the severity of dust sources in conventional mining operations. Three underground coal mines were surveyed using gravimetric samplers and GCA RAM-1 continuous dust monitors. Two additional mines were surveyed using only GCA RAM-1 monitors. Data on dust control methods were acquired during the survey, also. The results indicated that cutting/drilling and loading out were the dustiest operations during a conventional mining cycle. Roof bolting, shot firing and product transport were less severe dust sources.

Jan 1, 1983

By Robert L. Davidoff

Growing domestic and global demands for mineral resources have established an imperative need for developing comprehensive, versatile mineral supply analysis evaluation tools. The Minerals Availability System (MAS) of the Bureau of Mines is meeting this need with its computerized Supply Analysis Model (SAM). This paper describes the SAM system and the quantitative methods used by the MAS for mineral supply analyses. The MAS evaluating process consists of deposit identification, tonnage and grade determinations, engineering and cost evaluations, financial analyses, and supply curve generation. MAS has developed this computerized system primarily to facilitate the maintenance of data information for the constructing of commodity supply curves. The SAM system presently has the analytical capabilities of simultaneously (I) evaluating many mineral deposits, (2) updating mineral supply information to reflect inflationary changes in costs and prices, and (3) conducting sensitivity analysis to determine impacts on mineral supply under various conditions. Many potential users in both government and industry will find the SAM system a valuable tool for policy analysis, forecasting, and planning. The SAM system has been constructed so that any types of information that are similar to the data elements in the MAS data base may be used to perform supply studies. The storage space needed for the SAM system?s programs, files, and output data is approximately 14 million characters.

Jan 1, 1980

Discovery of a deposit of magnetite ore estimated at 3 million tons and of quality sufficient to warrant mining has been located near Reading, Pa. by the Bethlehem Steel Corp. Last January; the company spent nearly $400,000 for about 1750 acres of farm land which had been valued at only about $50 per acre. It is expected that a pilot shaft 18 in. in diam will be sunk some time this spring. The ore body, delimited by diamond-drilling by Sprague Henwood, is said to measure roughly 2000 sq ft and 1000 ft thick, beginning 1500 ft below the earth's surface. In a continuing search for strategic minerals, the Atomic Energy Commission expects to put eight to ten diamond drilling rigs into the area 11 miles southwest of Blanding, San Juan Co., Utah early this year. The Commission's primary objective is the Salt Wash member of the Morrison formation. Holes 140 ft deep are expected to be drilled, with solid bit drilling through overburden, mudstone, shale and sandstone overlying the area.

Jan 1, 1951

By Fred R. Ingram

FOR the purpose of this discussion, let us consider that the Rocky Mountain region covers the area in the seven Mountain States, Idaho, Montana, Wyoming, Utah, Colorado, New Mexico, and Arizona, and before we discuss the needs of these states, let us define Industrial Hygiene. Industrial Hygiene is that branch of preventive medicine concerned with the protection of health, improvement of efficiency, and prolongation of life of the industrial worker; in short, adult health conservation. It includes in its broad meaning not only the prevention of occupational diseases, such as silicosis, lead poisoning, cadmium poisoning, and many others, but such relative problems as overcrowding, fatigue, and personal and mental hygiene; exposure to abnormal temperatures, pressures, and humidities; ventilation, heating, and lighting. It is a science which requires the combined activity of medical personnel (doctors and nurses), engineers, and chemists to evaluate the exposures and determine the means of eliminating the hazard. The engineer surveys the workplace, takes air samples at the breathing level of the workman, and analyzes the work exposure. The chemist determines in his laboratory the exact amount of toxic material collected in the sample, which represents the exposure of the workman. The doctor must diagnose the occupational disease, recognize its cause, and evaluate the disability. Together, all three must correlate the data obtained and devise efficient methods, medical or engineering or process changes, for controlling or minimizing the dangerous condition and for studying the effectiveness of these measures. The plant doctor, in addition, must aid in the readjustment of the incapacitated worker and provide facilities for prevention. Industrial hygiene, however, is of no avail without the understanding co-operation of management.

Jan 1, 1945