Search Documents

By L Clarkson, D Williams, P Redcliffe, F van der Wal

This research presents a snapshot and insight into the trends, patterns, and common considerations identified in the current standing of real-time tailings dam monitoring practice. Based primarily on information derived from concurrent research by the author (in form of a Catalogue of Real-time Instrumentation and Monitoring Techniques for Tailings Dams), challenges and opportunities when transitioning to a real-time monitoring system are discussed. Learnings and key considerations between different monitoring approaches are explored, including themes of limitations and advantages that were observed consistently through global supplier feedback.

Jul 1, 2021

By C. Kunze

ABSTRACT Although closure sureties cover works that are carried out during the existence of a mining company, certain liabilities are not known when the surety is established and become apparent only in a late stage of the closure phase, or even after the site has been relinquished. This paper supports the concept that these financial risks lend themselves to insurance solutions. Making insurance for unknown liabilities mandatory while defining unambiguous legal conditions could create a viable market for insurance products, provide a sufficient statistical basis for the calculation of premiums, and reduce costs.

Jan 1, 2013

By H. Reimer

The rates of return on investment are examined for several major Canadian mining companies. Because we are dealing with a highly cyclical industry, subjected to widely fluctuating metal prices, rates of return are examined over a 20-year period. Conveniently, the first decade examined reflects the period when the industry enjoyed incentives to develop deposits; during the second decade, incentives were reduced and the industry became the most heavily taxed industry in Canada. The high rates of inflation since 1973 have distorted the real rates of return on investment if one considers replacement cost.

Jan 1, 1977

By R. L. Unger

Restricted fields of vision are a common problem with underground mining equipment. Also, when lighting systems are provided, they may be positioned where they cause glare. This restricts the visibility around the machines even further. To help address these problems, the U.S. Bureau of Mines has developed a PC based software package to aid in the analysis of certain human engineering aspects of mining equipment design. The software is available for use by equipment manufacturers and mining companies for design work on new machines, as well as for evaluating proposed modifications to existing machines.

Jan 1, 1994

By Ph. D. Favreau, Favreau Patrice B. Eng, R. F.

Geology is important in mining by helping to identify the rocks which contain sufficient valuable ore to justify their excavation. Geologists give a geological name to each rock type, so geology is a player in blasting; when a blaster has successfully blasted rock of a given geological name at a former site, and he later has to blast rock at another site whose rock has the same geological name, then his first trial often is the same method as he used at the former site, since the geological name of the rock is the same

Jan 1, 2019

The Bureau of Mines performed cratering experiments in a homogeneous granite to test scaling laws for charge weights of 0.00476, 0.0220, 0.0900, 0.304, and 1.03 lb. Agreement among the data was best when empirical scaling exponents greater than one-third were assumed. Although the analysis showed that the best empirical scaling exponents were 0.37 for crater volume, 0.38 for crater radius, and 0.39 scaling for crater depth, all three crater dimensions could be scaled with a 0.38 scaling exponent.

Jan 1, 1970

By K. Duckworth

The treatment of Turam data by conventional procedures does not permit the interpreter to make any estimate of induced current magnitudes. This problem may be overcome by using an alternative data treatment procedure. It is shown that the conventional and alternative procedures are equally satisfactory in terms of their ability to provide the location of line currents and estimates of conductor quality. A full description and evaluation of both procedures is presented in conjunction with field examples to show how the alternative procedure may assist interpretation when used to complement the conventional approach.

Jan 1, 1973

By H. E. Wyslouzil

The highly competitive nature of the international iron ore market has forced producers to improve the quality of their pellets. The demand for low acid pellets suitable for direct reduction has resulted in an increase in the number of plants utilizing reverse froth flotation for silica reduction. Column flotation is being favoured for this service due to the low capital and operating cost of the equipment, as well as improved metallurgical performance when compared to conventional flotation cells. This paper describes the benefits of column flotation and discusses some important aspects of circuit design.

Jan 1, 1993

By P. M. Sullivan

Galvanizers' sal skimmings have been treated by two methods of leaching in attempts to produce preflux solutions suitable for use in galvanizing operations. Both water-leaching and acid-leaching procedures are effective, except in severely exhausted skimmings when water-leaching becomes impractical. A preliminary analysis of the skimmings is not required. Solutions in the recommended concentration range can be produced conveniently by control of pH, specific gravity, and chlorine content. A technician would require only a short period of training to be able to perform the operations described.

Jan 1, 1958

By K. A. Natarajan

The utility of yeast, Saccharomyces cerevisiae, in the separation of quartz from hematite is demonstrated. Yeast cells, as well as their metabolites, functioned as flotation collectors, depressants or flocculants and dispersants for hematite and quartz. Interaction between yeast and the above minerals resulted in significant surface chemical changes, rendering quartz surfaces hydrophobic and hematite hydrophilic. Mineral-specific extracellular proteins and exopolysaccharides were secreted by yeast cells when grown in the presence of quartz and hematite, respectively. Quartz could be efficiently separated from hematite through microbially induced flotation and selective flocculation.

May 1, 2012

By D. A. White

A simple model for hydrocyclone classification based on the crowding theory first put forward by Fahlstrom is presented. This is a mechanistic theory that postulates that the behaviour of a hydrocyclone is the result of an ordered process that is independent of its dimensions. The main variables that describe the process are the fractions of feed solids and water that are ejected from the underflow. A simple model is developed from basic properties of the classification process and is compared with theory. Agreement is good but improves when the cyclone has a high solids content

Dec 1, 1991

By R. Svensson

Mill linings play an important role in all comminution processes with tumbling mills. The selection of the lining profile and the lining material has a great impact on over-all grinding cost and mill throughput. The cost of the lining itself is minor in comparison with media cost, energy cost and the value of the material produced in the mill. The total scope must be considered when mill linings are selected. This paper presents case stories and explains the technology behind: -different lining profiles in rubber and steel -OREBED magnetic lining -Steel-cap rubber lining

Jan 1, 1994

By Webster S. Anderson

The design, development, and testing of hydraulic props to provide a lightweight, high strength, recoverable unit is described. Modifications in design incorporating threaded components resulted in the development of a lightweight hydraulic prop fabricated from aluminum alloy tubing. This new design facilitates interchange and replacement of component parts, and the physical properties of the material are not changed as they are when welding is required. The new prop is 65,000 pounds and has a maximum load capacity of a lower weight-to-load capacity ratio than the hydraulic props now available.

Jan 1, 1967

By David K. Sitler

Continuing advances in manufactured diamond materials used in rock cutting tools have created a new generation of high production tools for mining. This paper will review the three major manufactured diamond products available for the mining industry as supplied by General Electric Company, Specialty Materials Department, and examine the ways in which these materials are employed. As an integral part of this examination, the economic impact of manufactured diamond tools will be evaluated. Time and again, one will find that the premium price of these tools is economically justified when compared to traditional tools.

Jan 1, 1985

By Phil Dakin, Rajiv Chandramohan, John Lo Grande, Greg Lane

Crushing and grinding circuit availability is a critical design factor defining the installed equipment selection and the process buffers required to maintain throughput during maintenance. The comminution circuit typically accounts for a process plant’s largest capital expenditure and energy use. Effective process and equipment selection and layout optimization are crucial steps when combining the objectives of cost-effective design and high circuit availability in operation. This paper outlines fit-for-purpose design principles for optimizing process flow, eliminating standby equipment and reducing buffer residence time whilst improving maintainability and operability.

Feb 1, 2025

By F. L. Wideman

This report describes a computer program that is used for the calculation of the coordinates and elevations of subsidence survey pins located by intersection. This program was developed for the Federal Bureau of Mines by the Numerical Analysis Laboratory, University of Arizona. These calculations, although relatively simple, are both tedious and time-consuming when computed with a desk calculator and trigonometric tables. In this survey, a large number of pins were surveyed repeatedly, and it was evident that both time and money could be saved by using a digital computer.

Jan 1, 1962

By Cody Edwards, Ross Webb

5 miles of soft ground tunnel excavation for the SAWS W‑6 project finished months early despite difficult conditions. Success was achieved using TBMs and other equipment built long before most of the crew was even born. The old school means and methods easily adapted to the conditions encountered and were key to the project’s success. Unfortunately, an industry trend is to specify more “advanced” equipment which can sacrifice adaptability or productivity for a perceived reduction in risk. This case history discusses when traditional methods may be the best option.

Dec 1, 2022

By W. R. SHAHAN, W. R. Reed, J. P. Rider

Roof bolter operators may be exposed to high respirable dust concentrations on continuous miner sections with blowing face ventilation when bolting is performed downwind of the continuous miner. One solution to reduce the high respirable dust concentrations is to use a canopy air curtain (CAC) to deliver clean air from a filtered blower fan directly to the bolter operators under the canopies. The influence of CAC installation on the airflow and dust dispersion around the location of the roof bolter operator can be evaluated by using computational fluid dynamics (CFD). 

John Malcolm Fraser became Prime Minister in December 1975 when Australian voters gave him the biggest landslide victory in the history of the Federation. From the previous administration, Mr. Fraser has inherited an atrocious economic mess: a staggering budget deficit, an unrealistically overvalued currency, a 14% annual rate of inflation, mounting unemployment, and a demoralized business community. He has already tackled some of these problems with some measure of success; but he has been in power for barely a year, and it's too soon to see a turn-around.

Jan 1, 1977

By A. C. Rice

Aminopolyacetic acid chelating agents were added to separatory-funnel-scale solvent-extraction systems to determine the effect on separating rare-earth elements. Average values for separation factors between adjacent elements obtained with Primene JM-T2 increase 36 percent when EDTA is added to the aqueous phase. Adding HEDTA or DCTA also improves separation factors for certain rare-earth elements. Percentage of extraction and the separation factors exhibit marked sensitivity to concentrations of amine, chelating agent, and hydrogen ion. The chelating agents improved separation in Primene JM-T, BHDA, and Primene 81-R extraction systems.

Jan 1, 1963