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By Bruce Macdonald

Operational monitoring of slope stability can be achieved by space based InSAR monitoring platforms. Natural and man-made rock slopes are monitored using a novel stack-based InSAR method that exploits both persistent point scatterers (PS) as well as coherent distributed scatterers (DS) such as areas of pavement and sparsely vegetated surfaces. The new method, Homogenous Distributed Scatterer (HDS)-InSAR identifies InSAR targets by using adaptive multilooking of statistically homogenous pixel neighbourhoods combined with thresholding the differential temporal coherence of each target candidate with respect to its surroundings. HDS-InSAR preserves PS and therefore forms a direct generalization to our proven DualScale-PSI method. The density of HDS exceeds that of PS by more than an order of magnitude often providing essentially continuous coverage over urban and industrial landscapes featuring a mix of infrastructure with mostly bare soils or rock surfaces. The improved coverage enables better definition of surface motion and underlying geology, which will lead to superior interpretation of the geophysical mechanisms causing the surface deformation, e.g. through improved integration with 3D deformation modeling. We illustrate the performance of our new HDS-InSAR method compared to DualScale-PSI using displacement results from Vancouver, Canada; Bingham mine, USA; and the Palabora mine, South Africa.

Jun 1, 2012

By D. Berkley

Off-gas systems often become the limiting factor in production increase and environmental projects. Any upgrade or new off-gas project needs to address control instability issues, instabilities that can result in safety hazards, significant loss of system capacity and/or emissions to the environment [1]. In addition, the design engineer must optimize system configuration and equipment size for the new operating conditions, to have a technically feasible and economically viable project. Dynamic simulations can be used for addressing both the control stability and the design optimization issues. This paper illustrates how the dynamic simulation of transient processes and of their control system can be used in "real life" situations for these purposes, presenting the example of an electric furnace off-gas system design.

Jan 1, 2005

By R. L. Brown

The burning sulphide ores in the Sullivan Mine generate sulphur dioxide gases. This paper is concerned with a description of the environmental impact of SO2 on air quality in the mine and on the surface in the vicinity of the mine. As a result of surface caving, SO2 has been able to vent to surface and winds have carried it into one residential area of Kimberley. Monitoring practices are described.

Jan 1, 1977

By N. Dave

"IntroductionIn the mineral processing industry, certain minerals such as uranium, thorium and vanadium, etc., are selectively extracted with high degree of purity from solutions containing variety of other impurities by solvent extraction process. This separation process consists of bringing two immiscible or partially soluble liquid phases in contact, where mass transfer of one or more components takes place by ion exchange under certain controlling parameters such as pH, salt concentration and temperature. The processes taking place are primarily physical because the solutes being transferred are ordinarily recovered without chemical change. For efficient extraction more than one stage is required and the solutions are recycled counter currently through other stages. A multi-stage counter current solvent extraction plants essentially consist of four circuits namely: extraction, water wash, stripping, and solvent scrubbing. In extraction circuit the desired mineral is extracted at a certain pH from an aqueous solution onto an organic solvent by bringing them in contact with mixing in large mixer-settler units. The mixed solutions are allowed to settle and separate into component organic and aqueous phases in horizontal settlers by providing sufficient residence time. The solutions are then moved counter currently to other units- the aqueous from the underflow and the solvent organics from the overflow of the settler. The solution streams coming out of extraction circuit are loaded organics and barren aqueous or raffinate solution. The loaded organics are washed with water in a water wash circuit to remove transported impurities from extraction circuit. In the stripping circuit, the desired mineral is stripped selectively from the solvent phase back into an aqueous phase with a stripping agent at a selected pH. The solution stream leaving, stripping circuit are stripped organics and pregnant strip (aqueous) solution. The stripped organics are scrubbed off other loaded impurities with a conditioning solution in, scrubbing circuit and the cleaned solvent is re-used in the extraction circuit.A typical solvent extraction plant for uranium extraction and purification at Agnew Lake Mine is described in this chapter."

Jan 1, 1989

By P. Sauriol

This work addresses the design challenges and demonstrates the capabilities of a novel water transfer factor measurement apparatus. Several measurement concepts were screened on the basis of their water transfer factor accuracy using Monte-Carlo generated virtual experiments. The most promising measurement concept was assembled and tested to assess its actual measurement accuracy. For these concept validation experiments, the polymer electrolyte membrane fuel cell was simulated by adjusting the water injection rate to corresponding levels. Combining the anode and cathode measurements, the water transfer factor accuracy was typically better than 0.01. Real-time measurements of the water transfer factor on both anode and cathode sides of a polymer electrolyte membrane fuel cell were achieved. The anode and cathode side measurements were in good agreement with each other; however the anode side measurements were generally more reproducible. A parametric study showed that stream humidification plays an important part in the water transfer across the membrane electrode assembly. Finally the water transfer factor along the channel of a 300cm2 co-current fuel cell was obtained by using a series of six 50cm2 sub cells. The results were in good agreement with predictions from a recently proposed model.

Jan 1, 2005

By W. R. Cowan

The availability of mineral aggregates for construction purposes is rapidly declining through inadequate resource planning. restrictive zoning and legislation , and competing land uses. The Geological Branch of the Ontario Ministry of Natural Resources has undertaken to provide aggregate inventory reports for all townships designated under The Pits and Quarries Control Act, 1971, and eventually for all towns hips in heavily populated areas. The reports contain maps and recommendations for extractive zoning by municipalities; of necessity only the largest deposits are given priority recommendations. It is intended that these reports should improve the resource planning in areas underlain by large aggregate deposits. The inventory is only possible because a concentrated effort has been made to map the Quaternary geology of populated areas over the last ten years. Future needs require that we develop methods to determine the extent of poorly defined and buried aggregates and that we look for natural alternatives.

Jan 1, 1978

By G. Eaton

Safety management is an important mortal and business function in construction. Contractors have traditionally tracked and reported lagging indicators, e.g. fatalities and lost-time accident rates, to measure their safety performance and stay in compliance with relevant regulations. Over the last several decades, contractors became more proactive in their approach to safety and developed programs that track leading indicators, e.g. safety audits and safety climate. In particular, safety climate measures workers? perception of safety management and its effectiveness in the workplace. Past literatures indicated that, while some industrial construction contractors ignore safety climate measures, others are limited by a lack of a formal means to measure safety climate. In this study, a survey approach is used to measure an industrial construction contractor?s safety climate through three key areas: management commitment, job control, and general safety climate. As a pilot study, a total of 214 individuals at a fabrication facility participated in the survey to verify the validity and effectiveness of the proposed survey approach. This survey study also confirms that job control and management commitment have a positive correlation and that worker demographics have an effect on respondents? perceptions of management commitment.

Aug 1, 2013

By D. E. Deegan, G. Holcroft, T. P. Johnson

"The rising cost of extracting metals from existing traditional deposits, increasingly stringent environmental regulations and a greater awareness of corporate social responsibility issues are all factors in stimulating the examination of mine tailings and small-scale alluvial deposits as a potential source of new raw materials. Furthermore, despite tougher economic times the demand for commodities remains strong, in no small part as a result of the growth of the world’s emerging economies.This combination of social and economic factors looks set to continue in the long term which will encourage greater recovery of materials from previously ignored sources such as mine tailings and ores from alluvial deposits.An expansion in the recovery of useful materials from mining-related activities is likely to require the use of robust and innovative techniques that have a built-in degree of future-proofing; DC plasma technology is one such technology.As a result of its ability to separate the valuable metal and minerals from the waste material while destroying hazardous compounds, Tetronics’ DC arc technology offers an alternative approach to resource recovery from a wide range of mine ores. Harmful cyanide compounds and the vast quantities of water used in conventional hydrometallurgical processing are avoided when plasma processing is adopted. DC arc technology also brings additional benefits, including: the extremely effective destruction of organic materials, the conversion of the inorganic material into a re-useable aggregate and the high tolerance of the process to fine and dusty materials. This paper presents details of Tetronics’ DC arc technology as one of the key pyro-metallurgical solutions available for the recovery of valuable materials from traditional mine ores and tailings, as well as giving specific examples of how the technology has been successfully employed in the recovery of enriched slags, ferroalloys and other metals."

Jan 1, 2016

By Helge B. Wurst, Michael P. Cipold, Jan F. Bachmann, Claus C. Bachmann

"In washability, the objective is to establish the set of maximum possible separation performance criteria for a given mineral feed. The method of choice for this has been the conventional sink-float analysis. Time, cost and safety aspects of the sink-float method have prompted the search for a new approach for establishing separation performance criteria, especially as performance levels of separator plants can be maximized if reliable information based on an analysis of washability in conjunction with particle size distribution, elemental constituency becomes readily available. The new method to establish washability and associated performance information utilizes at least two measurement technologies concurrently: single energy x-ray transmission and image processing. For porous or very inhomogeneous materials the results can be refined further by using dual energy x-ray transmission and image processing. The value of the collected data increases considerably if the washability data were additionally available in time to be considered in the control of the process plant. The incorporation of an automated washability monitor gives near real-time data that would impinge positively on the profitability of the plant operation. The method was extensively tested with a range of sample with different densities, varying from 1 g/cm³ (coal) to 5 g/cm³ (iron ore).INTRODUCTIONWashability of minerals like coal and iron ore is expressed by a curve or graph showing the results of a series of float-and-sink tests. Several of these curves are drawn to illustrate different conditions or variables, usually on the same axes, thus presenting the information on one sheet of paper. Washability curves are essential not only for the design but also for the operation of preparation plants.In determining the washability analysis, particle density is the underlying feature of all washability curves. Conventionally, the particles are separated into density fractions by immersing them in fluids of a predetermined density followed by skimming of those particles that stay afloat. The particles remaining afloat thus have a density lower than that of the fluid they were subjected to. The particles that remained at the bottom of the fluid container thus had a higher density higher than that of the fluid. By progressively increasing, for example, the density of the fluid and immersing the remaining particles so as to be able to skim the next density fraction, the particles would be fractionated into density groups. The liquids used range from aqueous solutions to organic liquids to suspensions. Unfortunately the liquids used for this separation process are often toxic and expensive. It stands to reason that a new method of determining washability is sought."

Jan 1, 2016

By Ron Hatch, M. K. Witte

"INTRODUCTIONThe proper selection of carbon for a gold carbon in pulp (CIP) circuit involves careful evaluation of several physical, chemical and economic factors. A series of evaluations are required to maximize gold recovery at the lowest capital and operating costs, whether the carbon is selected for an existing gold mill circuit or a new mill under design.Although evaluation may proceed through various stages, it is the intent of this paper to outline some of the preliminary testwork that should be carried out to screen potential carbons for a particular application.An examination of the specification sheets supplied by the various carbon manufacturers may indicate some desirable properties on which to make cursory selection. This exercise by itself will not provide the basic data needed for selecting the best carbon for a particular ore pulp and metallurgical circuit. The necessity of further metallurgical evaluation is indicated by the fact that different carbons perform differently depending on the physical and chemical nature of the leach pulp. In the case of an existing mill, actual leach slurries using mill water are available and should be used for testwork. In the case of new mills, leach pulps must be prepared to simulate the proposed circuit.Five coconut shell activated carbons were obtained from various suppliers, all reported to be 6 x 16 mesh carbons recommended for CIP circuits. A metallurgical evaluation was made utilizing two leach pulps with significantly different characteristics. This paper describes the test procedures utilized and the results obtained from the testwork."

Jan 1, 1985

By S. H. Ash

No single factor in modern civilization has played a more important part in the lives of our people than mechanization in industry and to it civilization owes much of its progress. In no industry has mechanization met more opposition than in coal mining, where ?the introduction of mechanical equipment has been opposed on many fronts for economic and social reasons. The term 'mechanization? as used in this report refers to the application of machinery to cutting, loading, and transporting coal from the face to the mine cars. During 1933, 84.7 per cent of the underground production of the bitu-minous-coal mines of the United States (1) was cut by machines, while in Washington only 17.6 per cent was machine-cut. Information in this report has been obtained from personal observations and from operating officials in the Roslyn-Cle Elum coal fields, especially D. R. Swem, manager of coal operations, and Thomas Murphy, superintendent, of the Northwestern Improvement Company, to whom the author is indebted for assistance. INTRODUCTION Although Washington coal-mining problems relating co mining methods, ventilation, drainage, and preparation of coal have been discussed in many publications, little has been published on mechanization in this region, principally because it has not been accepted generally that mining machines, mechanical loaders, and conveyors are necessary or economically adaptable to the variable and steeply inclined coal beds of Washington. Production of coal in Washington reached its maximum in 1918, when 4,128,424 short tons were produced; from that year, the trend was downward until 1934, when production was 1,383,103 short tons, the lowest since 1898; for the past two years, production has risen steadily.

Jan 1, 1937

By P. E. Cavanagh

Introduction A comprehensive study of the economics of processes for smelting iron ores has been made by the Ontario Research Foundation on behalf of the Ontario Research Commission. This survey has included investigations of all processes in commercial use, and proposed processes which are still in the experimental stage. The two main objects of this work were to discover (l) whether any known processes would be particularly suited to present and future Canadian conditions, and (2) whether any new process would be of assistance in solving the present scrap shortage in Canada. The future prospects of the Canadian iron smelting industry have changed radically in the past ten years. For nearly twenty years before 1939 no iron ore was mined in Canada. The ore used was imported, mainly from the United States and Newfoundland. The economics of iron blast-furnace smelting always force the location of blast furnaces near the source of coal for making high-grade metallurgical coke, and near the market for iron and steel, rather than near the iron ore. Blast-furnace installations in Canada are confined to the north shores of the Great Lakes with ready access to United States coal and ore and the major Canadian markets, and to Nova Scotia near the coalfields of that Province. This distribution of primary smelting capacity naturally results in relatively high prices for iron and steel in the West, the North, and in Quebec.

Jan 1, 1948

By Jason Palmer

"Water in mining is the commodity that has driven the mining industry for decades. Often used frivolously, modern economic and social pressures are forcing change to use less water and to improve the quality of water and effluents. Used in many processes, water is ultimately consumed in tailings disposal and technologies which can increase the recovery of water are constantly being developed. Filtration and thickening are often seen as competing technologies for water recovery however new cases are developing that show significant advantages can be achieved by combining the two technologies to develop the most effective solution. Supported by case studies this paper investigates the merits of each of the technologies and which strategies of combining the two produce the best outcomes.INTRODUCTIONMineral processing applications generally require water for the processing of ores, whether utilising physical or chemical methods. Water is first added in the milling stage and additional water added as required throughout the circuit. Water losses from the circuit are principally associated with the tailings stream. Optimised water recovery is necessary both because it is a scarce commodity and to minimise the environmental impact.Water recovery is usually accomplished through a sedimentation or filtration processes. Water can be removed from the tailings impoundment by evaporation but this does not improve the mine’s water consumption. The water recovery methodology also determines the water quality; increasing water recovery concentrates solutes in the process water and may create recirculating loads of fine solids."

Jan 1, 2016

By F. Habashi

Lead is an ancient metal. The alchemists related it to the planet Saturn. It was largely obtained by smelting galena which generally contains small quantities of silver. That is why the metallurgy of lead was closely related to that of silver and in some cases the ore was treated only for its silver content. It was also known during the Roman time that lead vapors were toxic. Lead has been produced exclusively by pryrometallurgical methods. Lead refining is a complex process because of the presence of deleterious impurities such as arsenic, antimony, and bismuth. In the nineteenth century lead played an important role as a material of construction in the manufacture of sulfuric acid. In the twentieth century tetraethyl lead was used exclusively as an anti-knock reagent. In recent years lead is mainly used for making batteries.

Jan 1, 2008

By J. W. Craig

THERE are, broadly speaking, three classes of refractories: acid, basic, and neutral. Fireclay, diaspore, silica, and the sillimanite group of minerals are included in the acid class, which for the most part are not very resistant to basic slags. The neutra! class includes chrome, graphite, and silicon carbide, while most important in the basic class are magnesite and dolomite. Although chrome is a neutral refractory, it has no sharp distinction from magnesitic refractoriness. The two are mineralogically (1) and chemically related, and there is available on the market a complete range of brick from straight chrome to straight magnesite. In many indus trial applications, one. type may be replaced by another. The present paper is confined entirely to such refractories. The following types of basic and neutra! brick, each sold under sorne special trade name, are available for use in Canada: (1) Burned chrome from crude ores (2) Burned chrome from treated ores (3) Chemically bonded (unburned) chrome-magnesite ( 4) Burned chrome-magnesite (5) Chemically bonded ( unburned) magnesite-chrome (6) Chemically bonded (unburned) high-iron magnesite (7) Burned high-iron magnesite (Regular) (8) Burned low-iron magnesite (9) Burned olivine-magnesite (10) Burned magnesitic dolomite-chrome (Magnecon) (11) Chemically bonded magnesitic dolomite-chrome (Magmecom) (12) Dolomitic brick

Jan 1, 1936

By J. R. Smith

"The Lake Dufault orebodies were discovered by deep surface diamond drilling. When a reasonable amount of outline drilling had been completed, the decision to go into production was made. The fact that shaft sinking, lateral development, the detailing of the orebodies and stope preparation were to be carried out as rapidly as possible necessitated very close scheduling.After a study of varions possible mining methods, an open-stoping system using long-hole blasting was chosen. Diesel-powered Transloaders were selected for the mucking and transportation of ore from the drawpoints to the orepass.At the time of writing, the choice of mining method appears to have been fully justified, although more time will be required to arrive at true operating costs and efficiencies."

Jan 1, 1966

The Cooperative Research Centre for Mining Technology and Equipment (CMTE) is funded by the Commonwealth Government, by its mining research members Ñ the Universities of Queensland and Sydney and the CSIRO1, and by its industry members Ñ BHP Coal, RioTinto R&TD, Hamersley Iron, Mining Technologies Australia, Pasminco, Shell Coal, WMC Resources, Advanced Mining Technologies, and Aberfoyle. The Centre conducts work aimed at improving the competitiveness of the Australian mining industry. The current work is focused in four areas: new mining and drilling systems, geological sensing, automation, and equipment maintenance and reliability. This paper describes much of the work in these program areas that relates to metalliferous mining.

Jan 1, 2001

By G. E. Norman, J. F. Jackson, A. L. Mckague

"The treatment of nickel-copper concentrate in the new smelter at Falconbridge Nickel Mines Limited, Falconbridge, Ontario, is described. The concentrate in a slurry form is partially roasted in a fluid-bed roaster and the calcine is smelted in an electric furnace. The roaster gases are treated in an acid plant. IntroductionSmelting began at Falconbridge in 1930 with the first blast furnace treating high-grade ore containing 2-3% nickel. In 1933, the Falconbridge concentrator was built and started producing a bulk sulphide concentrate containing 4% nickel. A sinter plant was built to agglomerate and partially roast this concentrate. The sinter was smelted in blast furnaces along with high. grade magnetic ore. Matte from the furnaces was treated in Pierce-Smith converters to produce shipping matte which was refined at the company's plant in Norway."

Jan 1, 1980

"The Cooperative Research Centre for Mining Technology and Equipment (CMTE) is funded by the Commonwealth Government, by its mining research members — the Universities of Queensland and Sydney and the CSIRO1, and by its industry members — BHP Coal, RioTinto R&TD, Hamersley Iron, Mining Technologies Australia, Pasminco, Shell Coal, WMC Resources, Advanced Mining Technologies, and Aberfoyle. The Centre conducts work aimed at improving the competitiveness of the Australian mining industry. The current work is focused in four areas: new mining and drilling systems, geological sensing, automation, and equipment maintenance and reliability. This paper describes much of the work in these program areas that relates to metalliferous mining. Mechanized Rock ExcavationThe disadvantages of the drill-and-blast excavation method are widely recognized and the last half of the 20th century has seen mining companies and mining research organizations aggressively pursue technology to excavate rock by other means. As discussed below, despite considerable effort and large amounts of funding, the quest for mining’s “Holy Grail” has been unsuccessful in all but the weakest rock types.COMRO (the Chamber of Mines Research Organisation) supported by the South African gold mining industry, spent three decades and (probably) tens of millions of dollars developing prototype drag bits and, later, impact breaking machines aimed at the mechanized stoping of narrow, tabular reefs. This work has not yet produced a commercially-attractive mining system. Work continues in South Africa to mechanize these stoping operations although now the emphasis is on the use of diamond-wire sawing techniques. This work remains in the experimental phase.Both British Coal and Germany’s Bergbau- Forschung spent many years developing techniques trying to extend the range of rock types which roadheaders could cut economically. Again, although new knowledge was produced, it is difficult to claim that any new commercial mining systems emerged from this work."

Jan 1, 2001

By J. Gray, J. Peck

As the turn of the century approaches, traditional open pit mining methodologies and processes are being modified through the introduction and use of new technologies. As in other industries, the personal computer is dramatically changing the traditionally conservative mining industry by allowing mines of varying size and capacity to increase their productivity and efficiency through the use of easy to use, office software. Computer-based monitoring and control systems are also being used more frequently to measure and optimize, in real-time, the performances of operating equipment. When communicated to an end-user, this information can provide accurate and timely answers to questions of how much, where, when, and by whom. This capability forms the foundation of a more comprehensive, proactive management and planning facility where, ultimately, information acquired from the producing equipment will be used to optimize and control machine and human activities. As these technologies mature and become essential tools in a mine, they will eventually serve as the basis for more robotic and autonomous mining operations.

Jan 1, 1999