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By Vitor Fonseca de Barcelos, Jair Carlos Koppe

Our society is experiencing a digital revolution. Technology is demonstrating its significant potential for mining industry. In this paper are presented the measured and estimated impacts of applying new technologies on blasting operations in a copper mine.

Feb 1, 2020

By R. D. Brittain

In order to analyze and control the transport of harmful trace-element impurities in various smelting processes, it is necessary to have fundamental information about the chemical thermodynamic properties of the pertinent condensed and vapor phases. This paper describes recent thermodynamic studies of the gaseous arsenic sulfides and of the activity of arsenic in a copper-iron sulfide matte phase. These studies were carried out by high temperature mass spectrometry and by effusion vaporization techniques, which permitted clear identification of the molecular species involved, a decided advantage in such complex systems. The nature of the results obtained and comparisons with previous interpretations will be described.

Jan 1, 1983

By S. Seetharaman, Du Siehen

"In the processing of molten metals, it is extremely important to monitor continuously the concentration levels of various minor elements. In the production of common metals like copper, iron and aluminium electrochemical sensors involving solid as well as liquid electrolytes are being increasingly used to measure the concentrations of minor elements. The present paper deals with the electrochemical principles underlying these measurements and the possible errors involved. One of the major difficulties in the case of the solid electrolytes is to correct for the consequences of the electronic contribution to the conduction of the electrolyte.The application of the electrochemical sensors for molten metals processing involves designing of these probes to withstand the industrial operating conditions. In this respect, significant achievements have been made with respect to the design of oxygen probes for liquid metals in general and liquid copper in particular. Some of the salient design features are discussed in the paper. The application of auxiliary electrodes for impurities in molten metals like phosphorus in copper and silicon in iron are taken up. The development of oxygen sensors for slags is given special attention. Recent developments in the field of sensor technology, as applied to metals processing are highlighted.1. IntroductionThe rapid technological advancement today require precise control of the process parameters and the impurity levels. Most of the molten metals processing in industrialized countries are often steered by suitable computer models, either phenomenological or simulations based on theoretical principles. These models often require that the process parameters are continuously monitored so that the progress is followed and modified suitably as and when required. It is common practice to measure temperatures by incorporating temperature sensors at the various strategic points of the reactor. In the case of monitoring the composition changes in the various phases, the method of sampling followed by routine chemical analysis involves a time lag as well as uncertainties in sampling and analysis. In this respect, electrochemical sensors have the advantage of generating accurate data when properly applied and increasing attention is being paid in the development of electrochemical sensors for various common species in molten metals processing. In the present paper, the developments in this area over the years are outlined and typical process applications are discussed. A greater emphasis will be laid on sensors based on oxygen conducting electrolytes and their application to the production of common metals like iron and copper."

Jan 1, 1996

By J S. Kuszmaul, T O. Aspinall

The applicability of environmental geotechnics for erosion management is increasing in importance worldwide. The environmental impact of mining and evolving environmental legislation has been receiving increased attention worldwide in the last two decades (Bradfield, Shultz and Stone, 1996). The potential impacts associated with unstable spoil dumps from mine operations is the focus of concern both by the mining industry, environmental legislative agencies and members of the public. This is because of the need to increase the reliability of erosion prediction and in the minimisation of costs for spoil dump design. Engineered slopes of mine spoils may be stable at the end of construction, but they can deteriorate over time. Engineering design of mine spoil dumps seeks to reduce the potential for such erosion damage through correct selection of an initial stable landform scheme (Goh, 1997). The design of mine spoil dumps must also conform to the specifications of evolving legislation. The Queensland Environmental Management Overview Strategy (EMOS) states that, for minimised degradation of the surface area due to erosion during the development of a project, the erosion rates should be between 12 - 40 tonnes/hectare/year and that the depths of rills and gullies be limited to less than 30 cm (QDPI, 1988). The aim of engineering design is to ensure the long-term stability of the spoil dumps. The implementation of effective planning and operating procedures through recontouring and grading assists in the reshaping of spoil dumps to a safe, stable and non-erodible environment.

Jan 1, 1998

By Q. Han

A modified cast-on method has been developed to reinforce aluminum castings with steel insert. Defect-free bond between the steel insert and the aluminum casting has been consistently obtained. Data obtained from a push-out experiment indicated that the bond strength was much higher than that obtained using the Al-Fin approach. This paper introduces this modified method in four sections: the coating of the steel pins, the cast-in method, microstructure characterization, and the bond strength. The section on the coating of the steel pins contains coating material selection, electro-plating technique for plating Cu and Ni on steel, and diffusion bonding of the coatings to the steel. The section on cast-in method deals with factors that affecting the quality of the metallurgical bond between the coated steel and the aluminum castings. The results of microstructure characteristics of the bonding are presented in the microstructure characterization section. A push-out experiment and the results obtained using this method is described in the section of bond strength/mechanical property.

Jan 1, 2015

By A. Gronningsater

Introduction As is well known, the fight between the blast furnace and the reverberatory furnace in copper smelting during the second decade of the century ended with a victory for the latter, a result which must largely be attributed to the introduction of flotation methods. To my knowledge, no new blast furnace has been blown-in at any American copper smelter since the War. As the metallurgy of nickel, up to and including matte smelting, is generally considered a close parallel to that of copper, the introduction of reverberatory smelting in the big new smelter of the International Nickel Company at Copper Cliff, built in 1928-30, seemed a logical adherence to a well established trend. In view of these facts, considerable comment was made when Falconbridge Nickel Mines decided to retain the blast furnace in their smelter built about the same time, in 1929. A presentation of the reasons governing this choice should therefore be of interest. The basic principles underlying the Falconbridge practice, and the considerations guiding the successive steps in the operations, will be discussed in the following. To understand the problems involved, the character and mode of occurrence of Sudbury ore must be kept in mind. Large amounts of disseminated ore are generally present. Although the gangue usually runs only about 50 per cent Si02, the ore hoisted as a rule contains more silica than needed in the smelting operation; until recently this excess was removed entirely by hand picking (in later years supplemented by magnetic sorting methods), a difficult and not very satisfactory method, in which 'the border line between ore and waste is entirely arbitrary, and therefore too much depends on the judgment of the picker.

Jan 1, 1934

By Frank B. McKune

This is something new in my life. A lot of you men here today I do not know, and some I do know. So if you have any remarks to make, I wish you would give your name and the name of your company. This is the first Acid Meeting which has been held under the auspices of the National Open-Hearth Steel Conference, and I hope it is a success. Whether it is a success or not depends entirely upon the support we get. If it does get good support, I have the idea it will be continued as a regular feature of the National Open-Hearth Steel Conference. We all think we have pretty good practices. But we can all learn and I hope that you, gentlemen, who take issue with the things someone else has said will stand up and give your opinions. Otherwise, the meeting will fall rather flat, and we won't get a great deal out of it; and there will not be enough interest shown by the National Committee to continue to place the meeting on the regular yearly program.

Jan 1, 1940

By H. Kenworthy

Small batches of fluorspar flotation concentrates were made into nodules and pellets on a laboratory scale. Several of these were rated acceptable by laboratory evaluation methods. The most satisfactory pellets were produced by mixing fluorspar with about 12.5 percent of water, by weight, and 4 percent of organic binders. These binders) for the most part) originated from petroleum and wood-pulp industries. They were generally difficult to handle and were not easily incorporated with the fluorspars tested. Most of them seemed to have an aversion for damp fluorspar and had to be forcibly mixed with the fluorspar; which was then formed into pellets by pressure. Substitution of fuel oil in varying amounts in the binders enhanced the mixing and penetrating qualities of these binders but at the same tire tended to make the pellets more porous. Tall oils performed the same function to a lesser degree and usually decreased the water absorbency of the finished pellets. Heat-treating temperatures to set up these binders were moderate -about 5000 F. for 30 to 50 minutes was usually enough for both drying and heat treating. Nodules made with 1-1/2 to 2 percent of bentonite as a binder were easily mixed and formed. They required a high degree of heat (about 1,500° F.) to develop their strength and were quite water-absorbent when finished. Two fluorspars were examined for weight and fluorite loss after heat treatment at similar temperatures. Both showed a definite wej.ght and analytical loss of fluorite. Bentonite was used also as a binder to successfully nodulize finely ground oxides of iron, manganese, and nickel.

Jan 1, 1951

By H. Tomlinson

Fatalities from falls of roof and coal are responsible for the death Of more than 1,000 miners annually in the bituminous coal mines of the United States, or practically one-half of the total fatalities In and about these mines. The men are killed by falls singly or in small groups and little or no publicity is given these accidents as they lack the spectacular features of gas and dust explosions. As a result, the public and even the miners have the impression that accidents from falls of roof and coal are just one of the unavoidable hazards of the coal-mining industry. This belief is not true. Accidents caused by falls can be avoided largely by the application of sound engineering principles, by education, and by proper leadership in the industry, just as gas and dust explosions and accidents caused by explosives have been reduced in recent years. The necessity for studying falls of roof and coal becomes apparent by referring to the following data from a table by Adams and Chenoweth:3

Jan 1, 1933

By Joklik, G. F.

Most publicity about the copper industry nowadays is focused on the adequacy of ore reserves and on excessive mining capacity. These concerns, stemming from public awareness of actual and potential shortages and oversupplies, relate to production rather than consumption. Perhaps the reason for this one-sided view is that copper is thought of as a commodity which is conspicuously traded in world markets, rather than as one of many industrial materials that serve today's rapidly changing technology. Copper differs from other widely traded commodities in that its real cost of production has progressively increased since World War 11. The reasons for the increase are identifiable by analyzing operations in one of the world's large producing centres, the copper province of Arizona. Another respect in which copper differs from some other commodities is that increases in demand occur less automatically in the case of copper than they tend to in commodities whose consumption is more directly related to population growth. The copper industry's current inability to generate and attract needed investment capital is attributable to these differences between copper and other commodities; it suggests that the concept of copper purely as a commodity is outdated. The key to the problem is better integration between the activities of copper producers and users. Depending on circumstances, integration takes various forms- for example, investment tied to long-term sales con- tracts between producers in developing countries and consumers overseas; common ownership of producing and manufacturing facilities in industrialized nations like the U.S.; and consumer-oriented research and marketing by the copper producers.

Jan 1, 1978

By Julian Malnic

The emerging marine minerals exploration and mining industry is currently focused mainly on the technical elements for its success such as developing exploration and mining technologies. However, in one sense, the technical challenges are quite soluble whereas those arising in the fields of the environment and public opinion could present this new generation of miners with problems that are far more difficult to overcome. One need only look at the issues currently faced by mining projects on land to see how powerful the new forces of so-called ?civil society? are in stopping mineral developments in many countries. From the geographic viewpoint, there are many countries but there is just one ocean, so the impacts experienced by any one operation are likely to have pervasive repercussions throughout the industry. A well-oiled NGO development protest lobby will see leverage in resisting this new industry and will seize on the single-ocean angle. The Australian Minerals Industry has established a voluntary Code for Environmental Management that provides an active and valuable model for satisfying the ?court of public opinion? and in delivering economic results to industry that are in current jargon, sustainable. An explanation of the Code for Environmental Management, and the reasons behind 44 companies representing more than 300 operations and 85% of Australia?s sizeable mineral production being signatory to it will be given. Participants see it as a means to future shareholder wealth.

Jan 1, 2000

By Gerald H. Luttrell, Mohammad Rezaee, Roe-Hoan Yoon, Rick Q. Honaker, Aaron Noble, Abhijit Bhagavatula, Michael J. Kiser

A field study was undertaken to experimentally measure the concentrations of rare earth elements (REEs) contained in the process streams generated by a group of 20 coal preparation plants located in the eastern USA. For each site, representative samples of clean coal product, coarse refuse, and fine refuse were collected. Each sample was then partitioned into preselected size and density classes by wet screening/sieving and float-sink testing. The resultant products were dried and subjected to laboratory analyses to determine ash contents and rare earth element concentrations including Yttrium and Scandium. A detailed analysis of the database generated by this exercise showed that coal-based products from these preparation plants contained significant quantities of rare earth elements. In particular, the coarse refuse streams currently discarded by the 20 plants examined were found to contain a sufficient tonnage of REEs to satisfy the current domestic demand for these important elements. The data also showed a strong positive correlation between ash content and REE concentration, which suggested that the primary association of REEs in eastern USA bituminous coal sources is likely within fractions containing inorganic impurities. This association was well described using a simple power equation relating ash content and REE concentration. The ratio of heavy-to-light rare earth elements was discovered to be significantly higher in organically rich fractions of clean coal, suggesting that mineral impurities intimately associated with carbonaceous matter have elevated concentrations of heavy rare earth elements. A similar trend was observed for a grouping of rare earth elements (Y, Nd, Eu, Tb, and Dy) that are likely subject to near-term supply shortages. Finally, the database showed that a linear correlation existed between La for many REEs of interest, although there were several notable exceptions for some high-value REEs (Lu, Pr, and Tb).

By A. C. Smith

The U.S. Bureau of Mines conducted a study to evaluate the effect of ventilation on the water spray patterns of automatic sprinkler heads. Experiments were performed in a rectangular tunnel with pendent, upright, pendent sidewall, and horizontal sidewall sprinkler heads at air velocities of 0, 150, 300, 500, and 800 ft/min. As the air velocities were increased, there were significant shifts in the total coverage areas, density distribution patterns, and the maximum coverage densities for all types of heads. The pendent and upright heads exhibited upstream shifts in total coverage in the direction of the air-flow ranging from 4 to 6 ft, while the downstream coverage distances were extended up to 14 ft at the 800 ft/min airflow. The shift in upstream coverage distance for the sidewall heads ranged from 6 to 12 ft, while the downstream coverage was extended up to 22 ft at 800 ft/min. The results showed that airflow can have a significant effect on the coverage characteristics of automatic sprinkler heads and needs to be considered in the design of effective sprinkler fire suppression systems for ventilated areas.

Jan 1, 2010

By John B. Knaebel

This paper, describing the milling operations of the St. Joseph Lead Co. at Balmat, N. Y., is one of a series of similar papers being prepared by the United States Bureau of Mines on practice at various mills in the United States, Canada, and Mexico. The company also operates a mine end mill at Edwards, 12 miles northeast of Balmat. Mining practice in the district, as exemplified at the Edwards mine, is described in another information circular of the Bureau of Mines.3 The writer gratefully acknowledges the generous cooperation of the company officials which made this investigation possible, and wishes to thank R. J. Mechin, manager, P. W. Wolf, mill superintendent, and F. G. Kuehl, assistant mill superintendent, for their helpful assistance. Especial thanks are due J. S. Brown, geologist, for supplying information on the characteristics of the ore, and to C. F. Jackson, principal mining engineer, U. S. Bureau of Mines, for helpful suggestions.

Jan 1, 1932

By C. Van Den Heuvel, C. B. Van Buuren

BIOX® has been successfully demonstrated over the past 2 decades for the recovery of gold from refractory sulphide concentrates. To date 12 successful BIOX® plants have been installed in 8 countries spanning 4 continents with the 13th installation currently nearing completion in the Philippines. In 2010 BIOMIN introduced the ASTER™ process for improved water balances in commercial BIOX® applications by supporting tightening environmental legislation on water usage and availability in both arid and tropical regions. Previously, a common challenge for BIOX® plants was the inability to recycle thiocyanate containing water due to the low tolerance of the organisms. ASTER™, a biological thiocyanate and cyanide destruction process, renders a non-toxic solution for re-use in BIOX®. Two commercial ASTER™ plants are in operation with the 3rd ASTER™ plant under construction in the Philippines. A 3rd BIOMIN technology, specifically developed for double refractory ores is available for implementation. The HiTeCC process has shown considerable success on ores where competition from disseminated carbon has rendered ineffective gold recoveries. Through HiTeCC, gold is desorbed from the carbonaceous matter by manipulating the ionic strength and temperature of conventionally treated CIL product. One Australian commercial plant utilises HiTeCC while a 2nd installation is set for commissioning 4th Quarter 2014. BIOMIN’s premier solutions for refractory gold processing are described herein.

Jan 1, 2014

By E. Gaucher, D. C. Gagnon

"The paper refers to methods and concepts used in the computer treatment of banks of geophysical, geochemical and geological data, relating to the exploration of massive sulphides. In particular, a data bank of 400 drill holes on independent conductors can be used to calculate probability levels of intersecting a certain quantity of sulphides according to the characteristics of the conductor. Inversely one can, using the data bank and some cost assumptions, simulate and optimize the cost of intersecting a certain quantity of sulphides by selecting drill targets among conductors according to conductivity, magnetism or gravity. Problems of noise, inherent in any simulation, are illustrated in this paper by the results of a study of the nomenclature of volcanic rocks of 27 drill holes by forty geologists. Compilations of data banks are long and timeconsuming, and it would help to standardize to allow exchange of data. We believe that such efforts may result in the discovery of more mineral deposits and at a lower cost. The present study is supported jointly by SOQUEM The New Jersey Zinc Co. and Cominco Ltd."

Jan 1, 1973

By C. Tasker

Introduction In the Early part of 1930 the Ontario Research Foundation was asked by the Minister of Mines, the Hon. Charles McCrea, K.C., M.P.P., to undertake a technical and economic investigation of the Northern Ontario lignite deposit. This investigation has been under way since June, 1930, and has necessitated considerable work at the deposit, in the laboratories of the Foundation, and at test plants in Europe. All the work has been carried out in active co-operation with the Provincial Department of Mines, the Deputy Minister, Mr. T. F. Sutherland, and several of his technical colleagues being associated with members of the staff of the Foundation on the Advisory Committee, which has met at frequent intervals to co-ordinate and direct the various lines of research. An interim report was made to the Minister of Mines by the Director of the Foundation, Dr. H. B. Speakman, at the end of December, 1932, and is at present under consideration by the Minister. This report deals with the extent and character of the deposit, the methods and costs of mining, and the methods and costs of processing raw lignite, the characteristics of certain lignite products, and the technology and economics of present fuel utilization by railways, industry, and domestic users in northern Ontario. It is not the purpose of the author to discuss in this paper either the geology of the deposit or the economics of the mining, processing, and utilization of lignite, but rather to deal briefly with some of the technical problems investigated by the Foundation during the study of the characteristics and methods of utilization of Northern Ontario lignite. Some mention, however, of the work carried out to define the extent of the deposit is a prerequisite to any discussion of the nature of the lignite.

Jan 1, 1933

By Bart de Graaff, Victor van Straaten, Edo Engel

The hot blast system is key ancillary plant equipment with respect to safe and stable operations during a long blast furnace campaign. Hot blast stove designs have been optimized to such an extent that in some cases, their lifetimes have surpassed the campaign lengths of the associated blast furnaces by a substantial margin, with the exception of the burner and a few critical areas. This article presents recent developments with respect to designing, building new and operating existing hot blast systems for a long lifetime and at optimized performance. These developments include fundamental improvements such as dome combustion designs as well as increasingly comprehensive packages for inspection, assessment and maintenance techniques. Examples of such techniques are burner replacement with the hot blast system at operating temperature, improved double shell approaches and TOFD measurement applications.

Oct 1, 2019

By N. S. Phala

Declining gold grades, mineralogical complexity of ore bodies, increasing input costs, more stringent conditions in the licenses to operate, and uncertain gold price dynamics combine to exert significant ongoing pressure on margins of gold producers. Innovative approaches of extracting the metal from its ores are required to realize value from existing and future assets. In a conventional gold processing plant, size reduction of mined ore to produce floatable or leachable product is a significant cost contributor. A step change in cost reduction will be attained if radically energy efficient grinding approaches can be developed, replacing tumbling mills. In the path towards that goal, some quick wins are possible through waste rejection before grinding, and pre-treatment of mill feed to reduce grinding energy demands. Gold locked in complex mineralizations puts pressure on margins by increasing cost per oz (typically high $/t and low metal recoveries) in the hydrometallurgical steps. Gold miners are primarily price takers. The current narrow range of gold uses (predominantly investment and jewellery) is not an entirely desirable state. Some diversification into commercial uses would potentially be a price stabilizer. In this paper, promising research directions, some not always fully explored in the gold metallurgy research space, are highlighted to stimulate radical innovation for substantial value enhancements. The author strongly believes a shift from a traditionally conservative and incremental innovation approach to a more aggressive one, across all aspects of the gold metallurgy value stream (processes to products), is what the industry needs. Keywords: gold metallurgy value stream, thiobaccilus ferroxidants, HPGR

Sep 1, 2012

By John W. Stevenson, Ted L. Sartain

Underground booster fan installations are currently employed in hundreds of coal mines throughout the world. Such installations, when properly designed and maintained, have proven to be safe and effective tools to provide desirable airflow volumes on sections or in areas of mines where the ventilation requirements exceed the capacity of the main fan system. In cases where an airshaft cannot be justified due to surface topography, depth of cover, or limited reserves a booster fan can serve the same purpose, be operational in a fraction of the time and at a substantially reduced cost. Booster fans are currently non-existent in U.S. coal mines. This is primarily due to lack of acceptance by the Mine Safety and Health Administration (MSHA), which has failed to acknowledge the merits of a booster fan system. Also, the absence of booster fan provisions in Part 75 of the federal regulations has led to the misconception that booster fans are legally prohibited in U.S. coal mines. In 1986, Jim Walter Resources, Inc. (JWR) developed and submitted to MSHA a plan to install and operate an underground booster fan at the No. 7 Mine. Detailed computer simulations were used to substantiate JWR1s position, that the booster fan could effectively provide the needed airflow on a developing section without adversely affecting ventilation in other areas of the mine. JWR also realized that numerous safeguards and operating procedures were essential for providing a safe system. Thus, safety features such as electrical interlocking, independent power supply, remote atmospheric monitoring, etc., were incorporated into the plan. This paper is a case-study that discusses JWR's proposed plan to install and operate an underground booster fan at No. 7 Mine. Unfortunately, MSHA's continued negative response has prevented implementation of the plan.

Jan 1, 1989