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By Mitchell J. Willis

Recovery of fine particles has been considered to be a major limitation of the classical flotation process. However, the beneficiation of kaolin, a naturally occurring fine ore, via flotation has been practiced over the last 40 years. Kaolin is valued as a white pigment, and therefore, the goal in kaolin flotation circuits is to remove the colored impurities to result in an acceptable brightness product. Kaolin flotation originated with a novel carrier flotation process, and later on carrier less flotation techniques were developed. The collector chemistry utilized to beneficiate kaolin is based on fatty acids, and recently hydroxamates have been successfully used. The purpose of this paper is to cover the flotation practice in the kaolin industry in terms of the history and the reagent schemes.

Jan 1, 1999

By P. C. Thakur

In gassy coal mines, some methane drainage is essential for mine safety, but the ratio of total methane drained to total methane produced by the mine can vary from 10 to 70 percent. The volume of methane not captured is diluted by ventilation air and vented to the atmosphere. Since captured methane can be processed and sold, it makes sense to maximize methane drainage from coal mines. This paper describes ventilation and methane drainage schemes to achieve these goals.

Jan 1, 2003

By Alberto Sarmentero

Venezuela, once a world's top gold producer until 1886 Witwatersrand discovery, did let fall its role then because of a serious lack of infrastructure and population, and lately (since World war II times), because of discouraging mining and taxation laws, laying upon an oil prizes bonanza. Recent research leading to estimates of about 5.000 mt. of gold, mainly related to the greenstone belts of the Guiana Precambrian shield outcropping in Venezuela, are opening the scope for both Government and international investing and mining companies, for gold exploration and development projects in the country. This paper overviews Venezuelan Gold mining industry, as seen from the point of view of a participating mining company.

Jan 1, 1989

By M. M. Veiga, M. Koehoorn

This paper reports on recently completed research that investigated the health fabric of mining communities in British Columbia (BC), Canada. The project, funded by two national funding agencies and the BC Government, and supported by numerous provincial organizations, marked a collaboration between mining engineering and health researchers. The study employed mixed-methods. First, a quantitative phase merged census, mining industry and health data to investigate the relationship between declining economic conditions and health outcomes (mental illness and stress-mediated cardiovascular disease). Second, a qualitative phase investigated community health issues associated with the mining boom-bust cycle from the perspective of health and social service providers working in a northern BC coal mining community. Third health research findings were disseminated to potential knowledge users in the hope of enhancing mine impact assessing and integrated mine planning. The paper provides a synthesis of the research methods used in this project, and highlights the main indicators used and key findings. It concludes by identifying recommendations, and future research needs considered to be of particular importance to the health and sustainability of mining communities in BC, Canada and around the globe.

Jan 1, 2011

By R. Simon

Strain-burst phenomena are generally characterised by sudden releases of energy in a volume of highly stressed rock. Strain bursts are encountered in situations such as crown pillar bursts during cut-and-fill mining, face bursts at development headings cord floor bursts in deep shaft sinking. This paper describes a simple two-dimensional linear elastic FE modeling approach that leads to the calculation of the energy-release rate (ERR) and the total energy storage rate (TESR) in the rock-mass around the openings. The merits of using such energy parameters in the analysis of strain-burst problems for identifying areas of high energy release/storage are discussed through a case stud v. However, much site-specific back analyses are needed to better understand how strain bursts and energy parameters are interrelated.

Jan 1, 1999

By Andrew F. McKown, Lewis L. Oriard

Advances in explosives engineering are moving forward in several different aspects. These include improvements and new development in explosives products, the application of these products to blasting technologies, and the study of the peripheral effects of the use of explosives, such as ground vibrations and airblast. Topics of special interest in the last several years include new explosives and detonators, cap timing, explosive casting, high-speed photography, perimeter and slope control, air decking and mathematical modeling of blasting processes.

Jan 1, 1988

Information Technology has addressed those problems unique to senior management in the mineral industry. In general, these problems are those concerned with decision-making. Peter Drucker in his discussion of making effective decisions identifies five phases: (1) define the problem, (2) analyze the problem, (3) develop alternate solutions, (4) decide the best solution, and (5) convert the decision into effective action. The scope of the chapter by Guernsey addresses the first three phases which provide input to the decision-maker. The decisions to be made relate, in most instances, to the economics related to a mineral property or process. Computer models have been designed to generate these economic and financial evaluations. No one model is appropriate to the solution of all management's problems. In this chapter several applications are identified and summarized; a model for the economic evaluation of a mineral property is described in greater detail. The implementation of such models is dependent on the unique needs of management.

Jan 1, 1979

By S. C. Suboleski, J. W. Oberholzer

This paper describes research being undertaken by the Chamber of Mines Research Organization (COMRO) to assist the continuous miner operator and section foreman in the performance of their jobs. The project will initially provide visual assistance to the miner operator, and later it will semiautomate the mining (cutting) process. Using a technique known as "RF tagging," the project will also provide the section foreman with real-time or near-real-time information about the performance of the loading and hauling units. This data will allow the section foreman to quickly detect problems and take action where appropriate. The project is based upon the application of currently available technology, and in-mine testing results from the first phase are now available.

Jan 1, 1994

By Ernst Raphael

Mechanical drives of belt conveyor drives have experienced a huge amount of improvements concerning technology, manufacture and product structure that reduced investment and maintenance cost significantly. Most of these improvements were of technological nature in the'70s and '80s of this century; whereas, the present decade requires products that meet technical excellence as well as commercial advantages such as quick delivery, low cost and reliable spare parts supply. The best approach to meet these requirements is a highly modular and standardized system of reliable components that cover all demands a conveyor drive might require.

Jan 1, 1998

By D. R. Nagaraj

The practice of nonsulfide minerals flotation can be best characterized as an evolutionary blend of scientific theory and art. Although extensive fundamental studies have been carried out in the past several decades, and significant theoretical aspects have been developed, plant practice has developed the art form, often ahead of the theory, which is somewhat in contrast to sulfide minerals flotation. Several excellent review articles have been published in the past highlighting both the theoretical aspects and plant practice. An overview of nonsulfide flotation is presented here. Major differences in sulfide and nonsulfide flotation are highlighted. An assessment of the state of nonsulfide flotation, recent advances made in flotation processing, and industry needs are also given.

Jan 1, 1999

By Welland L. Ott, Hans J. Rumland

The Falconbridge Dominicana laboratory receives samples from all parts of the operation. Ore, metal and oil samples are taken by operating departments, gas and water samples by the laboratory staff. Physical sample preparation is essentially standard and produces comminuted samples for wet-chemical analysis and X-ray fluorescence analysis (XRF). T he main operating sections of the laboratory are described indicating in each case the type of instrumentation and method used, sample types analysed and comments on problems experienced. Emphasis is given to the sample preparation and X-ray sections especially with regard to the difficulties caused by our heterogenous ore material, calibration of the instrument and operational malfunctions. General problems related to our remote location and the tropical climate are discussed. Limited statistics on instrument availability, and stability, accuracy, precision, etc., are given.

Jan 1, 1979

By John A. Herbst

Mineral processors have evolved from "handbook-based" decision makers to "model-based" decision makers. With this evolution have come significant improvements through increasing productivity, decreasing capital and operating costs and increasing product quality. This paper traces the development of model-based decision-making technology over the last 40 years and documents the benefits resulting from systems optimization using these tools. Some speculation is ventured concerning the future of model-based decision-making tools and their use in the field of mineral processing.

Jan 1, 2000

By Richard H. Adams

INTRODUCTION With the discovery and depletion over the years of near surface ore bodies, exploration targets are tending to be at greater depth or overlain by various types of overburden which in some cases extends to considerable depth or is heavily water bearing. Access to these types of deposits for exploration and development often requires vertical shafts. This paper discusses the concept of small shaft engineering and construction, primarily for underground exploration but also for use as a low tonnage production facility or for mine ventilation. The option of a small shaft may be attractive in a number of cases, some of which are: The underground exploration of a deposit at depth where minimal expenditure is desirable until the potential of the deposit has been determined. The exploration shaft in many cases later serves as a ventilation way and second means of egress. Production of ore in a small tonnage/high-grade operation where decline access is impractical. For ventilation where other types of openings are impractical or would delay start-up of mine operations.

Jan 1, 1987

At periodic intervals-typically at the end of each month, quarter, and year- the accounting department in each division of a company distributes a set of reports to the division's managers. These reports describe the financial performance of the division and its major departments over the time period. They identify the revenues generated from the division's products and the costs incurred in their production. The results from individual departments are combined to determine divisional results, and the results from individual divisions are in turn consolidated to determine the results for the overall corporation. Cost reports for each of these activities show actual amounts, budgeted amounts, and the differences between the two. This reporting is carried out for the individual period and for the year to date.

Jan 1, 1999

By Steven Brown, Richard Stephenson, Richard Partch, Hongyu Wang

Filler technology has enjoyed a revolution in attention and achievement in the past half century. The genesis of the advancements is greater find a mental understanding of the synthetic chemistries for and physical properties of colloidal matter and instrumentation capable of characterizing particle size, shape and surface features. Several advanced chemical methods for processing powders are now employed in ceramic, electronic, imaging, medicinal and plastic technology. This presentation will highlight solution phase synthetic methods for in situ coating of fillers such as SiC, Al2O3, AlN and SiO2 and some properties of the product solids.

Jan 1, 2003

By L. G. Austin, R. C. Klimpel

Batch breakage kinetic tests were performed in a mill of 0.3 m diameter for a range of mill conditions. Accurate simulation required the measurement and use of factors which accelerated the specific rates of breakage of the top sizes as finer material accumulated in the slurry. These factors depended on the size distribution expressed relative to the top size, not the absolute size, suggesting that they are due to a packing effect not a rheological effect. The data simulated correctly a series of steady-state continuous tests in a mill of the same diameter providing values were corrected to the hold-up, ball load, slurry density, and size distribution measured in the continuous mill tests.

Jan 1, 1990

By J. M. Mutmansky, Aiping Wang

This paper outlines the patterns of methane emission in both longwall and room-and-pillar operations and discusses the effects that these patterns have on the decision as to whether the methane is most economically handled by ventilation alone or by means of a methane-drainage system in addition to ventilation. The costs of handling the methane in the ventilation system and the costs of implementing the methane-drainage system are discussed, as well as the costs related to the production of coal. The important issues of production slowdowns and gasouts are also discussed, as well as the proper response of mine management to such a situation. Suggestions concerning the keeping of production records related to methane problems are made, and the justification for more intensive economic analysis of coalbed methane extraction and utilization is discussed

Jan 1, 2000

By B. Elevli, M. D. G. Salamon

Production scheduling of an open-pit mine is one of the most important steps in open-pit mining. The mine's production schedule defines the distribution of cash flows and, as a result, directly influences the net present value (NPV) and overall economic feasibility of a project. The need to plan and operate a mine with an optimum production schedule has been obvious for some time, but the methods used to obtain such a schedule have not been so obvious. The current practice is to do a trial and error analysis by hand. In an attempt to improve the way production scheduling is currently done, a new computer based production scheduling algorithm was developed. This paper describes the fundamentals of this newly developed heuristic scheduling algorithm and its application to a gold deposit. The results of this case study show that the schedules, based on the new method, provide improved cash flows compared to production schedules done manually.

Jan 1, 1992

By K. V. K. Prasad

Stochastic simulation has been routinely used for performing risk and sensitivity analyses in a variety of fields. The commonly used means of generating the simulations has been the Monte Carlo approach, which usually employs a Simple Random Sampling (SRS) scheme of the variable distributions. This method is prone to sample clustering and requires a large number of samples to represent the distribution faithfully. This can become problematic for simulating complex processes where it is impossible to run an arbitrarily large number of replicate simulations. The Latin Hypercube Sampling (LHS) method uses a stratified sampling approach that assures representation of the input distributions for any given number of samples. In this paper the LHS and SRS approaches are compared, using a petroleum resource estimation example.

Jan 1, 1994

By Richard Engelmann

The mining industry, in particular the coal industry, has experienced the implementation of some major environmental regulatory programs during the past two decades. Over the coming decade the coal industry will probably experience only "fine tuning" of the regulatory programs they now operate under. The rest of the indus- try, however, appears to be on the verge of coming under a major new regulatory effort by the Environmental Protection Agency. Litigation and resulting court decisions will be the main force driving further changes in the SHCRA (Surface Mine Control and Reclamation Act) regulatory program. These changes are anticipated to be minor in compar- ison to earlier changes. EPA, however, is preparing a regulatory program which may carry as much impact to the rest of the mining industry as SNRA was to coal. Details of this program have yet to be worked out. Changes in the way EPAts Clean Air Program is applied to mining could also significantly impact the mining industry.

Jan 1, 1989