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By R Salmimies

Choosing a ceramic capillary action filter is often favoured in processes where low energy consumption is important, such as the dewatering of iron ore. In addition, the performance of the filter medium is essential, and the possibility to regenerate the medium is an advantage compared to other types of filter media. Although low, roughly 8 - 9 w-per cent for iron ore concentrate, and even cake moisture is the primary goal of dewatering, the introduction of better filtration processes can result in significant improvements of water economy and material efficiency.As industrial beneficiation processes are often complicated in their chemistry due to impurities originating from the ore itself, from the up-stream processing equipment and from the process water used, the characterisation of the filter media after usage might provide relevant information on what actually takes place during long operating periods. The aim of this study was to obtain new information on the fouling of fi lter media in an iron ore process to enhance and develop the regeneration process of the media in the future.X-ray diffraction and scanning electron microscopy were used to characterise ceramic filter media used in the dewatering of magnetite. Principal component analysis and discriminant analysis were introduced to identify trends in the data. Two types of media blockages were found to play an important role in an acidic iron ore dewatering process: fouling by slurry particles and by in situ crystallisation of a calcium compound, of which the latter originated from the combination of process water and process chemistry.

Jul 11, 2011

By M Boon, M Franklin

This paper outlines the journey of cultural maturation and management system development at the Mt Rawdon (MRO) gold mine from its acquisition by Evolution Mining Limited (Evolution) in late 2011 to 2016.Evolution embarked upon a series of projects that aimed to improve the operational consistency and implementation of change on-site, while leveraging off the existing strengths of the operation. This document describes the gaps that were identified, the processes used to close them, and the resulting cultural change and production outcomes, with a specific focus on how to optimise the culture at any mining operation.MRO had a history of four owners in less than three years when it became a key asset of Evolution. The site leadership team (SLT) decided to influence the culture at MRO by reviewing and upgrading the existing management processes.The first priority was to improve transparency and collaboration at the SLT level, followed by improving competency in project management. The next phase was to strengthen the internal communication using a deliberately designed network of meetings, communication screens and other initiatives. Once there was some traction, the focus moved toward increasing production volume and decreasing cost per unit by improving short-term planning and execution capability. Together with other initiatives, this resulted in improved collaboration between all functions, which in turn netted over 37 per cent mining production uplift.Following solid success, a process of prioritisation and alignment management was implemented. This supported the ‘Mine to Mill one operation’ ideal and allowed the SLT to decide month-by-month what actions were to be prioritised. These priorities incorporated production realities and longer term imperatives of the balanced business plan.Much of this work was completed during a period of declining gold prices and a relentlessly strong Australian dollar, making it difficult to justify spending money on improvement projects. This work proved critical for the operation’s long-term survival.CITATION:Boon, M and Franklin, M, 2016. Improving consistency of delivery at Mt Rawdon Operation, in Proceedings International Mine Management Conference, pp 305-320 (The Australasian Institute of Mining and Metallurgy: Melbourne).

Jun 22, 2016

By W. William Culver

James Douglas became known in the nineteenth century for two reasons fundamental to his mining career: (1) his experimental work with copper hydrometallurgy, and (2) his grasp of the idea that the quantity of copper ore matters more than the quality. On the first reason, there is a moment for any technology that’s critically important—when it moves from an area of scientific interest to one that companies are founded on. This paper examines the original 1869 Hunt and Douglas Copper Process in the context of science and engineering as they were in the 1860 and 1870s. It was a “humid” process, developed at Quebec’s Harvey Hill Mine. Chemically, the Hunt and Douglas vat leaching process succeeded, but not the original companies using it. On Douglas’ understanding of ore quality versus quantity, luck had it that the first company to field test the Hunt and Douglas Copper Process was in Chile. The Hunt and Douglas patent made that transition from experimental model to operational plant in 1870 when the Compañia de Minas de la Invernada was organized in Valparaíso. As a joint-stock company, Invernada spread the risk of investing in the revolutionary, but untested, Hunt and Douglas Process. The company brought Douglas to Chile as a consultant in 1871. His experience with hydrometallurgy, combined with what he learned about the copper business while in Chile, set him off on a career in metal mining that both surprised Douglas and made him wealthy.

By R. White, C. Doyle, B. Martin, C. Díaz, J. Hrepic, G. Cuthbert

"A program initiated to improve the service life of the magnesite-chrome refractory in the top blown rotary converters at INCO’s Copper Cliff Nickel Refinery identified slag corrosion as a major wear mechanism. Target slag compositions were established to produce a non corrosive slag. A plant program to achieve this target slag by the addition of controlled amounts of do lime and MgO was instituted. Addition to rates of the slag modifiers was optimized based on the slag composition assays achieved and the requirement to address corrosion effects on the high alumina content ladle refractory. A60% gain in TBRC refractory performance was eventually achieved and has been maintained yielding a net annual savings of $700,000. A significant gain in available converter operating time has also been realized.IntroductionINCO’s Copper Cliff Nickel Refinery utilizes two top blown rotary converters (Fig. 1) to smelt a blend of semi-refined nickel concentrates, producing a granulated nickel matte suitable for the adjacent carbonyl based nickel refining operation. The converter, or TBRC, operation is a batch process composed of feed charging and melting, oxidation of the excess sulphur in the matte, and reduction of residual nickel oxide. The final matte, containing about 78% nickel, is tapped at 1600°C from the converter and is granulated in a sluice equipped with high pressure water jets."

Jan 1, 1997

Jan 1, 1897

By Joseph P. DuCarme

The U.S. Bureau of Mines explored new methods and technology for extracting coal from the Appalachian Mountain region of the Eastern United States. These methods were aimed at extracting coal from thin seams and focused on the use of "roof-fall-tolerant" (RFT) mining concepts. These methods could be used on existing, abandoned highwalls or in conjunction with new highwall mining. The research was conducted using small-scale and quasi-full-scale physical models to obtain experimental results. Details are provided on (1) the quasi-full-scale model for cross-ridge mining, (2) the quasi-full-scale model for down-ridge mining, (3) the test results of these models, and (4) recommendations for future research. Significant results include demonstration of the RFT concept, a discussion of expected coal produced from these methods, and recommendations for future research.

Jan 1, 2010

By P Guj, J A. Bell

The valuation of early-stage exploration projects requires a valuer to take into account a large number of uncertain value drivers, the interplay among which may be non-linear. This paper examines some of the key value drivers including geology, target metrics, project area and maturity, the market and the psychology behind the decision-making process. The commonly accepted valuation methods and their underlying logic are outlined, including a view on why they evolved, what value drivers they attempt to address and their potential shortcomings. These methods include the multiple of exploration expenditure, geoscience rating, expected values and market based methods. The potential future valuation methods of replacement values and neural networks are also introduced along with how to minimise heuristic bias and error within the market-based approach.CITATION:Bell, J A and Guj, P, 2012. Exploration value drivers and methodologies, in Proceedings Project Evaluation 2012 , pp 17-28 (The Australasian Institute of Mining and Metallurgy: Melbourne).

May 24, 2012

By L. S. Cates

THE war is now behind us. We in the mining industry feel a just pride in the part that our industry and our men and our products played in defeating the enemy on the fighting fronts around the world. In five years of mobilization and actual combat, our mines and oil wells produced over 3 billion tons of coal, a billion tons of petroleum, 500 million tons of iron ore, 21/4 million tons of lead, 31/2 million tons of zinc, 5 million tons of copper, 14 million tons of bauxite, 17 million tons of sulphur, 68 million tons of salt, and 3 million tons of potash. It was an unparalleled performance. But what of today? Why the present low production and high costs? Among the black clouds in the mining sky none are so black as that presented by the labor situation. We know it is the result of the legislation and the interpretation of that legislation in the past ten or fifteen years. Since the passage of the Norris-LaGuardia Act in 1932, we have had nothing but a succession of laws, regulations, and decisions that have intensified the strength of the unions and made the operators of the mines and the sources of their financing prartirally impotent

Jan 1, 1946

By C. G. McLachlan

INTRODUCTION The work described in the following paper was under-taken with a view to determining, if possible, the relative importance of some of the phenomena on which flotation seems to depend, in the hope that, if this information could be obtained, it would be of value in dealing with the problem as a whole. At the outset, brief reference will be made to three papers which had a considerable bearing on the course followed in the present investigation. In 1919, Langmuir, in a paper on 'The Mechanism of the Surface Phenomena of Flotation', showed that mono-molecular films of very great stability could be produced on solid surfaces with oleic acid, but that pure paraffin oil, though spreading readily on a dean dry surface, was easily displaced by water.

Jan 1, 1926

By O. Terichow

A pendulum sclerometer designed by the Bureau of Mines is described. Its method of operation is given, along with the results of tests made on representative mineral samples of Mohs' hardness scale to determine the applicability of the device for research on rock testing. The sclerometer hardness values obtained from the tests indicated that reproducibility and accuracy were good. A quantitative comparison of the pendulum hardness values with microhardness and surface energy values published by other investigators showed good agreement on minerals with Mohs' hardness numbers of 2 to 9.

Jan 1, 1967

By Raymond O. Dannenberg

The gas-combustion retort developed by the Federal Bureau of Mines at the Rifle Oil Shale Project near Rifle, Colo., is a continuous, gravity-feed retort. The heat required to convert the kerogen in the oil shale to liquid oil is generated by the combustion of product gas and carbonaceous residue remaining on the retorted shale after the kerogen has been converted to oil, gas, and residue. A study of the effects of the process variables on retort operation, product yields, and product properties is important to the successful solution of the problems encountered in the development of a satisfactory process. Statistical methods were used to design the experiments and analyze the effects of the rate of shale throughput, the composition of dilution gas, the height of the shale bed above the air entry, air-gas distributor design, shale size range, and the ratios of the flow rates of the various gas streams entering the retort to the rate of shale throughput.

Jan 1, 1960

By Daowu Yang, Zhuo Ren, Hui Liu

"In this paper, the photochemical catalysis degradation effect of photocatalyst obtained by charcoal-supported nano TiO2 (nano TiO2 / charcoal) on the formaldehyde in the air was studied. The influences of the nano-TiO2 loading and the photoreactor structure on the efficiency of photochemical catalysis degradation of formaldehyde was reviewed.The nano - TiO2 / bamboo charcoal adsorption of formaldehyde, as well as the influences of a certain amount of formaldehyde after adsorption on its photochemical catalysis effect were discussed. The sol preparation process of Ce-doped nano-TiO2 was described. Experimental results indicated that: the surface of bamboo Charcoal still has a strong formaldehyde adsorption capacity after Supported by Nano TiO2.After adsorbing formaldehyde, the photochemical catalysis degradation efficiency of formaldehyde of the catalyst at a steady state is basically the same with new prepared catalysts’. When the thickness of the catalyst layer of the multi-ladder-type structure photoreactor is 2mm, the interval is 20mm, the absorption efficiency of formaldehyde of Nano- TiO2 / bamboo charcoal is the best . Nano-TiO2 undoped Ce responded with no degradation of formaldehyde after 2 hours, while the degradation rate of formaldehyde of the Ce-doped nano- TiO2 reached 15% 2 hours late, and the formaldehyde decontamination of the equipment reached 94%.IntroductionEmerging out of home decoration in the distribution of formaldehyde, benzene, ammonia and other indoor pollutants have been proved to be very harmful to the human body. Photocatalysis can eliminate air pollutants, in particular, can effectively degrade the air volatile organic compounds, it is a new method of air purification developed in recent years. the biggest advantage of photochemical catalysis degradation is green, this method can be available at normal temperature and pressure to degrade formaldehyde and other organic matter into carbon dioxide and water without secondary pollution.Nano-TiO2 have become the most studied photocatalyst due to its stable, non-toxic harmless, superior photochemical catalysis properties [1]. Initially nano-TiO2 powder was used as a photocatalyst, but it’s difficult to recover and easy to wear and tear [2,3]. Later, the TiO2 was used in the form of film loaded on some carriers, such as glass beads [4]. As the photochemical catalysis reaction occurred on the catalyst surface, only the organic matter adsorbed on the catalyst surface can be degraded, so the catalyst was requested that must have a strong adsorption. Combined the adsorption properties of bamboo charcoal and the photochemical catalysis activity of nano-TiO2 together. Made the photocatalyst by loading the nano-TiO2 on bamboo charcoal to degrade organic matter in the air. Nano-TiO2 semiconductor photocatalyst has a strong catalytic oxidation due to the photo generated hole of the surface [5,6],and has a potential application. Some studies have shown that nano-TiO2 photocatalysis activity can be increased by doping certain metal ions [7,8].The aim of our work in this study was to use bamboo charcoal load Ce-doped nano-TiO2 photochemical catalysis oxidation to degrade formaldehyde,and design a multi-ladder structure photoreactor, also prove the availability of the device from the theoretical and experimental."

Jan 1, 2011

By R. L. Grayson

The health and safety of employees, efficiency of the operating system and production are paramount goals in underground coal mining. The section foreman assumes responsibility for making his part of the total system function to meet these goals. However, section foremen often have not been prepared to assume the full range of their responsibilities upon becoming a supervisor. This discussion addresses the full range of section foreman responsibilities and concomitant authority. Management principles that must be mastered by him are presented, and performance expectations as well as criteria for their evaluation are examined. The benefits realized from effective foreman training are discussed.

Jan 1, 1985

By J. Kevin Cotchen

The results of "submerged arc" electric furnace processing of a variety of materials is discussed with respect to the process and products, including the characteristics of the products (e.g. TCLP or Toxicity Characteristics Leaching Procedure). The materials melted include slags and wastes containing various metal oxides including copper, tin, lead, zinc, chrome, nickel and other associated elements. The findings of these tests are compared to those reported in the literature for other operations treating similar "wastes".

Jan 1, 1992

By Marco Olper

The Italian company Engitec Impianti has developed a new electrochemical technology for the treatment of Electric Arc Furnace (EAF) flue dust generated in steel mini-mills. This process is based on a new and completely different concept from the Waeltz technology applied at present and allows, due to its modular nature, for an erection on the steel producer's site. Engitec Impianti spent US $700.000 constructing a 500 t/y throughput pilot plant at Pittini Group's Ferriere Nord mini-mill in Osoppo, Italy in order to demonstrate the process capabilities and obtain the data for a commercial plant design. The paper describes the pilot plant performances and the engineering criteria for a commercial unit of 10.000 t/y throughput. The feasibility study demonstrates a pay-back period of 3 - 4 years for the commercial plant.

Jan 1, 1995

By Joel N. Van Sant

The rapidly expanding economy of the West, with its growth of heavy industry, and increased steel production, is primarily responsible for the refractory clay industry's concern over the adequacy of the clay supply in States of the Great Plains and Rocky Mountains. Hence, the investigation by the Federal Bureau of Mines of the occurrence and use of refractory clays in North Dakota, South Dakota, Nebraska, Wyoming, Colorado, Utah, New Mexico, and Arizona has been encouraged by the major consumers and producers of this commodity. The Wyoming investigation is a part of the national program devised to close gaps in the domestic supply of specific types of clays to determine their characteristics and properties and to provide information that will assist the refractory-clay industry. Forty-two locations of clay-bearing rock in 17 areas in Wyoming were examined (fig. 1). Location 3 was not examined during this survey. Its description was taken from an earlier report. Locations 20, 21, and 22 were previously reported but were, also, examined by the Bureau. No samples were collected from these locations because field examination indicated that the shales were not refractory grade. The Hulett, Aladdin, and Newcastle areas are discussed in the section on the Black Hills district; the other 14 areas are described separately.

Jan 1, 1961

By J Leem, S Mehrishal, J Kim, A Fereshtenejad, J Song

Rock mass discontinuity mapping plays a crucial role in developing a reliable Discrete Fracture Network (DFN), providing insights into the distribution of geometrical and mechanical properties of discontinuities. This enables an accurate assessment of geotechnical infrastructure and mining excavations. Data obtained through conventional mapping approaches are substantially limited by factors such as accessibility and subjectivity. Moreover, these conventional methods may pose inherent risks due to manual techniques, exposing practitioners to potential dangers. Recent digital developments in remote surveying techniques offer opportunities for safer and more reliable rock mass discontinuity surveys. These technologies allow extensive three-dimensional surveying and the production of high-resolution 3D surface models, applicable at any time. This paper presents a workflow for digital discontinuity mapping employing drone technology and photogrammetry. Additionally, the capabilities and challenges of applying artificial intelligence (AI) algorithms in the rock mass discontinuity characterisation process are discussed.

Sep 1, 2024

By T. E. Sterner

The Bureau of Mines investigated the use of a chromatographic gas analyzer in determining the concentration of combustion products in gas produced during field and laboratory thermal oil-recovery tests. Several parameters (carrier-gas flow, cell current, sample size, and temperature) known to affect quantitative analyses were studied using a commercially available dual-column, dual-detector chromatographic gas analyzer which had been modified to provide close control of these variables. The apparatus made possible a much closer control of air-and gas-injection rates and provided adequate data for performing material-balance calculations and for determining oxygen utilization during the laboratory and field combustion tests. The chromatographic analysis also aided materially in evaluating and measuring bypassing and gas travel times and in detecting high-permeability zones that were present in the reservoir.

Jan 1, 1965

By E. S. Malloch

THE Great War forced the peoples of the world to recognize the importance of the wise development and use of the world's natural resources. Not the least, and perhaps the most, important, is the world's fuel supply- solid, liquid, and gaseous. Without fuel our civilization would be impossible, and mankind would of necessity have to congregate in the torrid zones of the earth's surface for at least six months of every year. Of the three classes of fuels the solid ones are the most plentiful, as well as being the most widely distributed, since few countries are entirely devoid of solid fuels of one kind or another. Until a hundred years ago wood was the fuel most generally used in this country, but since then coal has supplanted wood as a fuel in all its uses, except in the outlying districts and among the farming communities. For many years the supply of coal was thought to be unlimited, but as years went by more thought and study were given to the world's coal resources, until today not only are the limits known, but in one instance at least their depletion is predicted to be almost within the age of living men, unless more provident methods are put into practice for their winning and utilization.

Jan 1, 1928

By Chulho C. Song, Liam Coleman

Alkaline pressure oxidation (POX) is an oxidative pre-treatment option that is commercially used for high-carbonate sulfidic gold ores. The high carbonate grades within the feed ore shifts the ideal operating pH to a basic regime. Compared with acidic POX, alkaline POX typically requires additional steam input due to a lower sulfur oxidation load and a high rate of in-situ carbon dioxide generation that needs to be vented along with steam. The cost of this steam addition is the largest differentiator between acid POX operation and alkaline POX from a cost comparison. However, alkaline POX can offset these costs through reduced acid usage for pre-acidulation and decreased alkali reagent consumption for subsequent neutralization. This paper reviews the specific operating cost impacts of acid/base consumption between alkaline and acidic POX with ores which require pre-acidulation, the overall economics of alkaline POX, and the regimes in which alkaline POX is economically favorable. The findings aim to guide industry professionals in making informed decisions for alkaline POX adoption by providing a summary view of its operational benefits and costs, contributing to the development of cost-effective and sustainable gold ore processing techniques.

Feb 1, 2025