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By Stanley M. Jarrett

Operating one of the world's largest underground copper mines, Braden Copper Co. has been able to reduce its total accident frequency rate per million manhours by 84 pct, from 27.4 pct in 1945 to 4.45 pct for the first ten months of 1958. It has also won the Inter-American Safety Trophy for 12 consecutive years. The record may seem to indicate a secret formula, but there is none. The results stem only from hard work, and more and more of it.

Jan 11, 1959

By E. Wysocki

In the production of magnesium oxide, dolomitic lime and magnesium chloride are reacted to produce an intermediate product, magnesium hydroxide. Consistent product quality requires close monitoring of the soluble calcium hydroxide level during the reaction. Traditionally, this analysis has been done by manual titration; however, the product quality could improve with more frequent analysis and better control. A feedback control system was developed based on frequent automatic titrations, and reactor modelling was used to discern a control strategy. The system development and implementation are described.

Jan 1, 1984

By S. N. Sharma, William Davis

Because of diminishing energy resources and rising energy costs, every industry is forced to carefully examine its pattern of energy consumption. The copper industry is no exception; current smelting practice begs for technological innovations that would improve the efficiency of its energy utilization. The thermochemical simplicity of copper metal production, as shown in Fig. 1, is deceptive. Designed from the same basic principles, there are four major commercial processes either in use or under construction; and others, such as the Mitsubishi process, are being developed.

Jan 5, 1977

By J. D. Raulerson, J. M. Williams

This paper presents a comparative evaluation of several system currently being used or proposed for the transport of matrix from an open-pit mine to a large fixed plant. The matrix is a sticky, wet clay to be carried from 8-16 km (3-10 miles) at 910 t/h to 1.8 kt /h (1,008-2,000 stph). The system is complicated by frequent moves of the open-pit mine site and other factors, such as use of the clay component in land reclamation.

Jan 1, 1984

By D. R. Weir, R. M. G. S. Berezowsky

Pressure oxidation of gold containing concentrates and ores is an effective pretreatment for liberating refractory gold. This is particularly true when an appreciable portion of the gold is associated with sulfides and is not amenable to conventional cyanidation. A brief review of the literature on pressure oxidation of refractory gold materials is presented. The chemistry of the aqueous oxidation of arsenopyrite and pyrite is discussed. Data obtained on pressure oxidation and subsequent cyanidation of concentrates and ores tested at the Sherritt Research Centre are also presented.

Jan 1, 1985

By John W. Tieman

Coal is a term applied to vegetable matter (trees, grasses, etc.) which was subjected to heat and pressure through geologic ages. This resulted in a change in both the physical and chemical properties. Because its chemical composition is variable, geologists classify coal as a heterogeneous mineral rather than a homogeneous mineral. Peat represents the initial, unconsolidated stage in the development of coal. This coalification continues with time and the application of temperature and pressure to lignite, subbituminous, bituminous, and anthracite toward the theoretical graphite end member.

Jan 1, 1981

By Michael McDougall

"Suncor Inc. Oilsands Group, Mining Operation in Northern Alberta, Canada, has beenblasting to loosen the oilsands to increase production and decrease maintenance of the hugebucketwheel excavators for over twenty years. In 1991 an area of the mine wasencountered which had a working face in excess of 130 feet. In order to maintain theproduction objective, the blasting department took on the task of providing as much of ablasted face to work with as possible. In doing this Suncor has exceeded several knownrecords in production blasting."

Jan 1, 1993

By D. Lelinski, X. Nie, J. D. Miller, J. Hupka, K. Bukka

A preliminary characterization of soil components contaminated at a low level (7 nanocuries per gram) with toxic/radioactive metals has been carried out. Most radioactivity and metals content were present in the minus 100 mesh (<150 µm) size fractions. None of the size fractions examined qualified for uncontrolled disposal at dump sites, thus all material would have to be moved to discharge-controlled landfills. The metal content of the sample was below the limits for economical recovery, therefore eventual processing would be dictated by environmental concerns.

Jan 1, 1992

By R. Sainath, Wils L. Cooley

Continuous monitoring of ground bed resistance is essential to insure a low-resistance path for fault currents, lightning strokes, and electrostatic discharges. This paper explains the salient features of the continuous ground bed monitor and its applications. The importance of a low-resistance path to ground is highlighted. Sample readings obtained with the ground bed monitor are included, and typical applications of this instrument are illustrated. This effort was supported by the U.S. Department of Interior&apos;s Bureau of Mines under USBM grant G0144138.

Jan 1, 1979

North Stradbroke Island is a large sand mass offshore from south east Queensland. Dredging for mineral sands commenced there in 1956 and the rehabilitation discussed in this paper was commenced in 1967. The frontal dunes have a long history of instability, with little vegetation prior to mining. Re-establishment of the naturally stable contours is essential, and their rehab- ilitation is described. Vegetated high dunes present different problems requiring attention to regeneration of the native species. Methods developed over the past eight years are proving successful.,

Jan 1, 1976

By A. Cavero, M. Diaz

The annual rainfall at Minera Yanacocha&apos;s gold mining operations in northern Peru averages 1.2 meters. The influx of water into the operations is higher than losses to evaporation and by ore absorption which results in a positive water balance. To minimize water intake and maintain a balance, some special operating procedures are required, and a system involving diversion ditches, storm ponds, heap skirting and detoxification and treatment of excess water is practiced. An operation background is also reviewed at the beginning of the paper.

Jan 1, 1998

By P. Somasundaran, Yee-Ho Wang

Carrier flotation of anatase impurities from clay using oleate is compared in this study with conventional flotation. The role of relevant parameters such as carrier size, carrier amount, dissolved calcium and carbonate, conditioning speed, pH, time and temperature and collector concentration is investigated in order to elucidate the mechanisms involved in carrier flotation. Addition of coarse calcite particles is found to contribute towards the enhanced separation of anatase from clay mainly due to aggregation of anatase fines with calcite and the subsequent flotation of the aggregates.

Jan 1, 1980

Ask any mineral industry executive what he considers one of the most expensive aspects of getting a product to the ultimate consumer and invariably the answer will be transportation. Some company officials say that transportation charges alone account for over half of the total cost of most products. If these judgments are correct and a recent invention turns out to be the long-awaited breakthrough that shippers have been looking for, then many producers can look forward to slashing their delivery costs by 90%.

Jan 9, 1969

H. N. EAVENSON, Gary, W. Va.-Judging from our own experience, the statement that only 40 per cent. of the accidents are caused by the human element is very low. We have adopted all the measures that Mr. Wilson recommended, such as systematic timbering, use of permissible expolsives and practically everything that anybody has suggested or can think of, and even after all that has been done, done for several years, and a systematic campaign maintained all the time to reduce accidents, we still

Jan 4, 1918

By Alexander Filimonov, Yury Bloshteyn

The development of a high-efficiency control system for mine ventilation is a complicated scientific and engineering problem. As a result of high-costs and difficult conditions involved in experiments for the development and investigation of mine ventilation systems, simulation is a critical task in cost reduction and productivity. The paper presents the description of a universal simulation model for controlled aerodynamic processes in an Underground ventilation Network (UVN). The high-efficiency programming tool to design and investigate mine ventilation control systems (MVCS) is also suggested.

Jan 1, 1991

By C. E. Brechtel

Cooperative research efforts by the Bureau of Mines and Agapito & Associates, Inc., Grand Junction, CO, used a one-dimensional, finite-element computer model to simulate turbulent mass transfer in face ventilation of oil shale mines. The objective was to study the dilution of methane released by rubbled oil shale during blasting. A methane release rate function was developed from the back-analysis of field measurements, and the finite-element model was calibrated using tracer gas characterization data from tests of full-scale face ventilation systems.

Jan 1, 1989

By Upfold RW, Nguyen VU

The extraction and utilisation of metals and materials is the basis of modern civilisation, and will remain so for many decades, Traditional metals are facing some challenges and research is needed in specific areas, to improve metal extraction processes, to develop processes for newer metals and minerals, and to develop new applications, The shortage of metallurgists now becoming apparent in Australia is a further significant problem that needs urgent attention, and much more publicity is required for the Mineral Industry, as well as for the utilisation Industries,

Jan 1, 1986

By R. D. Hansen, R. R. Klimpel

This paper discusses the influence of frother type and dosage on recovery/selectivity in coal/sulfide mineral flotation as a function of particle size. It is shown that different frother structures exhibit quite different but consistent performance characteristics depending on the underlying particle size ranges involved as well as the dosage levels of both the frother and collector. The data presented on existing commercial frothers and some new special purpose experimental frothers is used to illustrate some general operator guidelines on proper frother selection and use.

Jan 1, 1987

By S. M. Brabyn

The wear in mild steel pipelines used to convey rod-milled waste backfill was determined and then compared with that obtained using a laboratory rig designed to simulate the wear condition in slurry pipelines. The relative importance of corrosion and abrasion was investigated under various conditions of water quality and particle size distribution. The laboratory rig was then used to evaluate other possible materials of construction for backfill pipelines. A preliminary assessment of the economic viability of pipelines made of alternative materials is included.

Jan 1, 1988

By W. Joseph Schlitt, Kenneth J. Richards, John D. Prater

Kennecott Minerals Company has developed a leach-hydrolysis route for treating flue dusts from copper smelters The flue dusts are acid leached in an oxygen atmosphere to solubilize copper and fix the arsenic, antimony, and bismuth as stable compounds Copper is recovered by cementation with Iron and the barren solution is recycled Molybdenum and other values may be recovered by modification of the basic flow sheet Results of bench scale and pilot plant tests are discussed in terms of the effect of operating parameters.

Jan 1, 1981