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By Paul G. Greenhill

The Australian Mineral Industries Research Association (AMIRA) was established by the Australian mineral industry in 1959 to develop and manage collaboratively funded research projects. Owned and managed by industry, it coordinates research that answers questions defined by the sponsoring companies of the projects. Now over 35 years old, the Association is an excellent example of what can be achieved through collaborative research and an industry - backed research organisation.

Jan 1, 2000

By A. V. Glembotsky, N. A. Greshnova, V. P. Seregin, V. A. Glinkin

Based on a new alternative depressant of zinc sulphide - dimethyldithiocarbamate- modern technology has been developed for the treatment of complex polymetallic ores. In addition to its general function (depression of sphalerite and iron sulphides to some extent), this double-acting reagent is a promoter for galena and silver minerals. Laboratory and plant tests, as well as industrial experience have all shown consistently higher silver recovery to the lead concentrate as compared with sodium cyanide, resulting in less pollution and a safer environment

Jan 1, 1995

By Ahmed I. A. Salama

The problem of estimating separation characteristics by utilizing mass distributions of feed and products is considered. The separation characteristics include mass yield and partition curve. The cases of mass balance and partition functions balance are identified. The developed techniques can handle the cases of two- and three-product separation. Actual data are utilized to demonstrate the proposed techniques.

Jan 1, 1992

By M. Karmis

The Virginia Center for Coal and Energy Research is leading an interdisciplinary coalition to identify potential carbon sequestration sinks in unmineable coalseams as part of the U.S. Southeast Regional Carbon Sequestration Partnership. The Virginia Center for Coal and Energy Research and the Eastern Coal Council are leading education efforts for the project, as well as specific outreach efforts in Central Appalachia in order to develop a process for stakeholder education and engagement in sustainable energy.

Jan 1, 2007

By John D. Welsh

Heap leach pad liners are important to leach operations for maximizing recovery of gold bearing solutions and minimizing potential environmental impacts. Liners must be designed so that they can be built economically, but careful attention must be paid to the potential for liner damage during installation or placement of ore on the completed pads. This paper summarizes field experience gained on several leach pad construction projects in Nevada. Both soil and synthetic membrane installations are discussed. Emphasis is placed on principles that should be considered during design to provide economical and practical leach pads.

Jan 1, 1987

By H. H. Murray

New and improved beneficiation techniques are available to allow the production of clay minerals of exceptionally high purity. This is particularly true for kaolins and smectites. Wet processing techniques include particle size separation, high intensity magnetic separation, chemical leaching ,flotation, and selective flocculation. The blending of clay minerals with other minerals provides opportunities to make special ceramic materials such as cordierite and other minerals that have very special ceramic properties including low heat expansion, high fired strength, low absorption, and other desired qualities.

Jan 1, 1990

By Debbie Nakamura, Daniel Tempelis, John E. Shamma

The Metropolitan Water District of Southern California established a Board of Consultants to assist them in administering the design and construction of the Inland Feeder Program tunnels. The Board acts as an expert review body for the owner, looking at key issues that can potentially impact the success of the program. The use of the Board evolved over the life of the project, and its composition was modified to better address the needs of the owner, and the Program requirements. The experience, function, and value of such a board is analyzed and discussed in this paper.

Jan 1, 2003

By K. D. Allen, M. J. Blattman

The problem of measuring the amount of rock removed during a given time interval is faced by most mining operations. Many methods have been developed with varying degrees of success, dependent upon the mining method and the availability of usable data. The Rosebud Mine has been in production for nearly two years, employing several techniques to estimate monthly production from underground production stopes. The use of three-dimensional solids generated from survey data has greatly improved the reliability and confidence of monthly production reports. The authors will summarize the methodology currently being utilized at Rosebud.

Jan 1, 1999

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 overall 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, 1995

By C. R. Rinschler, G. R. S. Smith

A high-strength, industrial-grade membrane filter- cloth capable of high flow rates and sub-micrometric particle retention has been developed. A filtration system using this filter- combined with special filtration techniques and using tubular-filters makes possible the filtration of many difficult-to-jilter slurries. Small, discrete, slowly-settling particles are formed into filter cakes that when pulsed of the membrane filter cloth do not redisperse but settle rapidly to form a dense filter under- flow. A positive separation of solids from liquids is obtained.

Jan 1, 1991

By Leonard A. Eros

In many mining applications it is not practical to use gravity takeups. In these situations hydraulic takeups are often utilized. Performance specifications are often compromised by designs which have inherently high internal friction and inefficient hydraulic designs. This results in performance which does not match the requirements of the conveyor system. A computer model has been built to check unit efficiencies and field measurements have been taken which verify the results.

Jan 1, 1993

By Michael C. Montoya, Craig Hopper

It has been well established that the ability to soft start a conveyor will give many benefits to the conveyor user. The effects of deceleration on belt tension have not been as extensively studied. This paper presents the findings of field measurements on the belt tension of a conveyor undergoing various rates of deceleration. The control of conveyor drive motors by Variable Frequency Drives (VFDs) allows the conveyor to be controlled during both acceleration and deceleration. The conveyor is allowed to ramp to a stop without putting unnecessary stress on the belt or conveyor structure.

Jan 1, 2000

By G. Jeffrey Taylor

The environment at the lunar surface is drastically different from the one we are used to on Earth. The Moon has one-sixth of Earth's gravity, virtually no atmosphere, a surface bathed in radiation and micrometeorites, large temperature gradients, low seismicity, and a dusty, rubbly surface. To successfully mine and process materials on the Moon and to mitigate degradation effects in the hostile lunar environment, these factors require new designs for equipment and development of new techniques and technologies.

Jan 1, 1990

By Thomas W. Camm

A WINDOWS-based object-oriented expert system for prefeasibility evaluation of hard rock mines is being developed at the Western Field Operations Center (WFOC) of the Bureau of Mines. Designed for use with the Bureau's Cost Estimating System (CES), this expert system assists an evaluator in choosing an underground mining method, and the related design parameters. The system provides the engineering and design guidelines necessary for an evaluator to perform a prefeasibility type cost estimate.

Jan 1, 1992

By Isiah M. Warner, Philip Oldham, John Kennedy, Bennett D. Lass

A new method for determination of residual flotation oils on beneficiated kaolin clays has been developed The method, which yields qualitative information, is based on fluorescence measurements employing a spatially resolved, polychromatic illumination source for excitation, and a two-dimensional detection scheme using a silicon-intensified, video imaging device The method was used to identify residual oils on a beneficiated, Washington County, Georgia, crude clay The results were compared to a similar qualitative analysis performed via capillary column gas chromatography using a flame ionization detector The video fluorometry was the preferred method of analysis

Jan 1, 1983

By L. A. Panek

A new pillar strength formula is presented. It incorporates a function [IF] of size and shape that takes into account the size-shape interaction effect as well as the enhanced strength exhibited by wide pillars. Existing pillar formulas, lacking these capabilities, are not suitable for extrapolating small-specimen test results to mine-pillar sizes and shapes. Interpreting compressive strength test results as function of [Y] reveals wide-pillar behavior in much old test data. Model relationships are discussed, along with their scaling implications.

Jan 1, 1995

By Ronald J. Doll

The selection and matching of the conveyor drive components (Figure 1) determine the initial cost, long term costs, and how well the drive performance is matched to a project's long term production goals. This paper will cover the specification criteria and considerations that should be included in a conveyor drive specification. It will also review the practical aspects of the specification's intent and the solicitation of alternatives.

Jan 1, 1998

By J. L. Post, L. Borer

Small seams of fibrous tremolite and actinolite commonly occur in many California counties. A number of larger seams of this fibrous material were mined from 1882 until about 1955. The fibers from these mines were used for making acid filters, battery cases and fire-resistant paint. With increasing population, new residential areas are being developed in the foothill regions, leading to increased contact with seams of fibrous amphiboles. These forms of asbestos can be particularly dangerous to human health. Thus, it is necessary to determine the locations of these mines and adjacent veins and to identify the specific amphibole minerals present.

Jan 1, 2003

By B. Govindarajan, T. C. Rao

A simulation of batch-flotation experiments was carried out using a simple empirical model to identify the process parameters that would give maximum yield at any given ash level. The relationship between the maximum yield values and the percentage ash-reduction ratio (ARR) has shown two regions where the collector and the frother dosages have individual influences on the flotation performance. Based on this observation, a simple "selection-criterion diagram" is proposed. This diagram can he used to select the process parameters to achieve maximum yield, for a given ash content of the concentrate and at any given flotation period.

Jan 1, 1997

By Dennis A. Beiter, William J. Francart

Barometric pressure changes have been an important consideration in the sealing of mines, especially in the case of mine fires. These changes are caused by storm fronts and regularly, on a daily basis, by atmospheric heating and cooling. In many cases, anticipation of these fluctuations in a mine sealing operation or recovery can be an important consideration when scheduling activities. The barometric pressure changes create pressure differentials across sealed areas, inducing airflows which may create explosive mixtures of mine gasses, cause intensification of fires, and create irrespirable atmospheres outby seals. These effects of barometric pressure fluctuations on mine fire sealing and recovery operations are discussed. Data available from the National Weather Service is also discussed as a tool for predicting barometric pressure changes.

Jan 1, 1997