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By Robert Hopler

This article, advocating having employees whose specific job would be to fire blasts in underground coal mines in llinois, was written 5 years prior to the establishment of the U.S. Bureau of Mines, and 2 1/2 years before the worst month in U.S. coal mining history, when 692 miners were killed in three separate explosions in December 1907. Obviously something had to be done to improve safety in the use of explosives, and having dedicated shotfirers was a good first step.

Jan 1, 2006

By Christopher Cloete Uys, Luis Manuel Poinha Valentim

The purpose of this workshop is to describe and demonstrate the use of SPEEDWAVE, a high speed data recorder, its VOD enhancements, and the software which binds the system together. The system was designed by TLC Sohware, SOUTH AFRICA. TLC is a company spedalising in the solution of engineering problems, using computertechnology as a base. TLC was founded in 1987, and has since been involved in many different.measurement, control, simulation and modelling projects. Wth respect to the blasting industry, TLC has, in conjunction with AECI South Africa/ICI, developed a tunnel mining design aid, a ring blasting design aid, a multkhannel seismograph and a laser surveying program. In 1989, TLC designed and built the BA800. a microcomputer-based high speed recorder. These recorders are still in use and are producing valuable results. Based on improved technology and with the field experience of the BA800, TLC has designed and developed the data recorder SPEEDWWE.

Jan 1, 1995

By Rosaire Emond

Le concept du forage horizontal a été développé voilà de nombreuses années. Différents types de plate-formes permettant le forage horizontal depuis une cheminée ont été conçus par divers manufacturiers ou opérateurs miniers. Entre autres, on connaît bien la griffe de montage Alimak à laquelle peut être fixée une plat-forme sur laquelle est montée une foreuse. En 1992, Ross-Finlay a développé sa propre plate-forme de forage qui à notre opinion améliore la flexibilité du concept du forage horizontal, en augmente la productivité et en diminue le coût d?ensemble tout en assurant une sécurité accrue des travailleurs. Tel que montré à la figure 1, la plate-forme employée à la Mine Kiena est composée d?un toit de protection contre les chutes d?objets et de deux passerelles de forage de forme carrée. Le toit et les passerelles sont fixées à une structure de 6.5 m de longueur équipée de deux assemblages de rouleaux (non montrés à la figure) permettant de faire glisser l?ensemble sur des rails Alimak. L?angle du toit et des passerelles peut être ajusté pour des cheminées dont le pendage varie de 65 degrés à 85 degrés.

Oct 1, 2001

By B. R. Reddy, Y. V. Swamy, B. V. R. Murthy, H. S. Ray

The Ni oxide was reduced with a CO-CO2-N2 gas mixture and the effects were observed of process variables such as roasting temperature, time and CO partial pressure. Extraction of over 90% of Ni was achieved by ammoniacal leaching of ore that had been reduced for 1 h at 760 degrees C under a gas mixture with a volumetric CO/(CO+CO2) ratio of 0.57. The kinetic data were found to conform to the Ginstling-Brounstein equation. The applicability of this model was confirmed by evaluating the apparent activation energy with the use of independently constructed differential and integral plots, which showed an excellent match

Dec 1, 1995

The Government signalled its intention in the Economic Statement on 17 December 1987 to improve the fairness of the taxation system and to facilitate the process of economic adjustment by: removing tax concessions that benefit some taxpayers at the expense of other taxpayers,ensuring that those who can afford it shoulder their fair share of the tax burden,securing a revenue base which will provide sufficient resources to maintain effective social services,reducing artificial protection and concessions that discriminate against some sectors, and encouraging confidence through an economic environment with a medium-term orientation. The Government has clearly stated to all sectors that tax preferences will be phased out and businesses need to look inwardly to their investment policies if they are to survive in an open economy. This paper will address the effect of these Government objectives on the taxation structure for all forms of mineral exploration in New Zealand. The present tax structure will firstly be analysed, in particular setting out the tax advantages available to the industry. The effect of changes to the tax system within the recent past which relate to mineral exploration will then be examined. Finally the paper will address the question of possible future changes, particularly in the light of Government's intention to move towards a tax system which does not provide an advantage for any one sector of the economy.

Jan 1, 1988

By Jean-Guy Levaque, Robert Ethier, Ron J. Elliot

This paper presents data gathered during a comprehensive study on the impact of improvements to fragmentation in a major Limestone quarrying operation. The full impacts of gains in fragmentation are tracked through the mucking, crushing, and grinding phases of the operation.

Jan 1, 1999

By Ken Norris

"Campbell Mine which has been in continuous operation since 1949 has undergone numerous operational changes in the past 3 years. This paper describes the process changes which have occurred at the Campbell Mill since 1991. The paper discusses the engineering, construction and startup of the effluent treatment circuit, the new oxide filtering and merrill-crowe precipitation circuit, and the changes to the pressure oxidation circuit. Particular attention is paid to startup problems and solutions to these problems. A review of the benefits and results of these process changes is also discussed. Future changes are also briefly reviewed with anticipated goals and expectations.IntroductionCampbell Mine is a gold mine 100% owned and operated by Placer Dome Canada. It is located in Balmertown, Ontario which is located 300 kilometres northeast of Winnipeg, Manitoba. The Campbell Mine has been in continuous operation since 1949, producing nearly 8,000,000 ounces. In 1993 Campbell Mine is budgeted to produce 289, 750 ounces of gold at a cash cost of $157 US/ounce. Daily mill tonnage is budgeted for 1,430 tons/day but has milled as high as 1,600 tons/day on a consistent basis. Recovery in 1993 is 93.4% and is budgeted to average 94.5% in 1994.In the 1992 edition of the proceedings of the Canadian Mineral Processors conference I described the changes that were made at Campbell starting in 1989. This paper continues where the 1992 paper ended and discusses the changes to the Campbell mill since that lime. The changes to Campbell since January 1992 have been numerous with capital expenditure in the mill exceeding $14.1 million. This paper describes three primary projects since that lime: the effluent treatment project ($5.5 million), the oxide leach/filtering and merrill-crowe project ($4.6 million) and the pretreatment project ($2.81 million). The focus of this paper is to highlight the justification of each project, the design and engineering, and some of the initial operational problems and solutions applied to those problems."

Jan 1, 1994

By R. K. McLimans, C. Knudsen, S. Bernstein, D. Frei

Computer Controlled Scanning Electron Microscopy (CCSEM) is used to analyze indivdual mineral fractions in heavy mineral sands. CCSEM is a fully automated particle analysis technique for the determination of physical and chemical properties of a large number of individual particles. CCSEM enables the precise and accurate determination of the modal abundances of individual mineral fractions (e.g. ilmenite, rutile, zircon, or garnet), their average chemical composition (and compositional variation), as well as their physical properties such as size (e.g. diameter and perimeter length) and shape (aspect ratio and circularity). A unique sample preparation procedure is used to produce representative polished sections from cylinders of raw sand samples such that thousands of grains are present in a polished cross section, but grains are not touching. The combination of this sample preparation technique with CCSEM enables the fully automated analysis of individual grains without the application of de-agglomeration or erosion steps to separate touching particles. Hence, CCSEM yields information representative of the entire area of analyzed grains without systematic bias due to neglect of rim areas by de-agglomeration or erosion steps. Therefore, the resulting data are determined with high accuracy, precision and statistical validity. Because the sample preparation is relatively straightforward, using raw sand samples, and all chemical and physical properties are determined in one analytical session per sample, CCSEM is a powerful cost and time efficient tool for characterizing chemical and physical properties of minerals in heavy mineral sand deposits.

Jan 1, 2005

By J Graaf, R A. Murrell

Gold Fields Australia is constructing two major ventilation shafts at the Wallaby gold mine in Western Australia. The new ventilation shafts are required to facilitate the long term ventilation strategy for the mine, thereby allowing continued extraction of ore beyond 1000 m below the surface. The construction work has involved all of the challenges that shaft construction can throw up, including challenging geotechnical conditions, unexpected high water inflows and major circulation loss during pilot hole drilling for raise boring. An extensive geotechnical and hydrological investigation program was undertaken prior to awarding the shaft construction contracts. While most of the risks were identified, several proved to be much more challenging than expected. The shaft construction methods included conventional sinking into the fresh rock profile in each shaft, followed by raise bore pilot hole drilling and reaming. A headframe was constructed for the first shaft, which was sunk to 92 m with a stage suspended in the shaft to facilitate the concrete lining and provide rope guides for the kibble winding. Drawing from experience when sinking the first shaft, additional ground pre-conditioning was implemented for the second shaft, which was pre-supported with continuous piles to 28 m followed by sinking to 50 m using a crane instead of winders and a headframe. Following the conventional sinking through the weathered zone in each shaft, the shafts were completed using a raise bore. The first shaft utilised a riser pipe and rotary vertical drilling system (RVDS) with the second shaft having utilised a dual rotary rig for pilot hole drilling. This paper reviews the site investigations undertaken, construction methodologies applied, the results achieved and the lessons learnt.CITATION:Murrell, R A and Graaf, J, 2017. Shaft construction at the Gold Fields Wallaby mine, in Proceedings 13th AusIMM Underground Operators’ Conference 2017, pp 321–334 (The Australasian Institute of Mining and Metallurgy: Melbourne).

Oct 16, 2017

By Ivan Carrasco, Benjamin Cebrian

Mining companies have traditionally organized their structure around a scheme easy to manage: Mining Department and Mill Department. In a challenging landscape for mining, with decreasing grades, increasing rock hardness and more expensive energy, this way to organize departments has resulted in internal disputes and often contradictory targets between both mine and mill. These compete for individual, separated budgets whose Key Performance Indexes often damage each other’s output. The results are increased total production costs and reduction of profits. Some companies have completed the first step in eliminating these inefficiencies by creating Fragmentation Engineers and Fragmentation Superintendents. With all the knowledge available on the overall fragmentation process and costs, in this document an overhaul of the traditional management structure is proposed. Is a step further Mine-to-mill and mine-to-leach programs. Since comminution is the most expensive step of the mineral exploitation, it should be taken as a whole, not divided into competing departments. Thus, mining departments should be re-grouped into: transportation, fragmentation and flotation.

Jan 1, 2014

By T. Bertke

This document assesses the environmental aspects of a preliminary design for processing kaolin clay as the domestic resource for recovery of alumina by a hydrochloric acid leach-HCl gas induced crystallization process. The report covers waste sources, control measures, and potential environmental and health effects applicable to the process technology.

Jan 1, 1980

By F. C. Gennari, D. M. Pasquevich

With the gradual exhaustion of natural rutile, there has been extensive research into its synthesising from lower-grade titanium minerals. The removal of Fe from pseudobrookite (Fe2TiO5) by chlorination was studied, using both isothermal and non-isothermal thermogravimetric measurements. Correlation of the results obtained from element distribution maps, scanning electron microscopy, energy-dispersive X-ray analysis and phases detected by X-ray diffraction in the chlorinated samples showed clearly two associated processes. First, the pseudobrookite particles reacted with chlorine and iron was removed selectively as FeCl3(g), leaving a solid residue rich in the TiO2 phases anatile and rutile, separated from an inner layer of unreacted pseudobrookite by a distinct interphase boundary. Second, chlorine allowed TiCl4(g) to form in the reaction bed, where it removed iron from the Fe2O3 crystals as FeCl3(g) and substituted Ti through a pseudomorphic reaction

Jun 21, 1905

By Zou Dingxiang

Rock blasting in the project of “Site Formation and Associated Infrastructure Works at Choi Wan Road and Jordan Valley” is the largest urban blasting project in the history of Hong Kong and also is rare in the world. More than 6.2 million of in-situ rock has to be excavated by blasting. The site is located in the center area of eastern Kowloon peninsula, surrounded by highways, registered cut slopes, high-rise residential buildings, MTR subways and the public utilities. The complex situations bring great difficulties and risks to the blasting works. A bird-view photo of the site is shown on Picture 1.

Jan 1, 2007

By Northcutt Ely

This volume summarizes mining and petroleum legislation in 25 jurisdictions of East Asia and the Pacific. Within these jurisdictions, primary attention is given to requirements that must be met in each country for acquisition of rights to permit development of mineral resources. Coverage includes: First, identification of the controlling laws or statutes governing minerals acquisition and reference to the administrative authority; second, analysis of the laws governing mines and quarries and their products; and third, analysis of laws applicable to natural gas, petroleum, and related materials. Where pertinent, sections dealing with historical background or administration have been added. In countries where minerals are subject to control of States or Provinces, those areas are considered separately from the central government.

Jan 1, 1971

By Nuno Cruz, Saúl Rodríguez

"When executing offshore bored piles there are several specific factors and problems to consider in order to guarantee excavation stability. One of the methods employed to carry out this type of work consists in setting up a floating work platform, typically a barge, and implementing a soil stabilization system that combines a partial steel guiding casing with third generation polymeric drilling fluids. The main aspects to take into consideration when performing offshore pile boring works are soil stabilization, project design, work methodology and operational aspects. An example of a work methodology problem arises before any pile boring work takes place as the steel guiding casing contains water, sometimes salt water. What to do with this water in order to replace it by an adequate polymer fluid will determine the stabilization capacity as soon as the shaft advances below the protection of the casing. Another example of operational problem may derive from barge movements while executing boring activities. This study is the result of extensive field data collection and concrete logging analysis from marine projects using polymers in different continents. The bored pile stability target was set ranging between 2% to 15% of concrete overbreak. Values above 15% or below 2% mean that there is a stability problem. Then the off-target pile’s data is collected, analyzed and classified under categories. Thus, a direct correlation is established between the problem category and the final results. Modifying steps in the pre-established construction methods or operational variables guarantees target results without the need to replace the approved construction methods. As a general conclusion, the worldwide experience in large diameter marine works, allows to provide truthful information and solutions for these problems. In knowing how to follow a logical sequence of work and applying adequate work methodology will be the key for success.GENERALBackgroundTo carry out the drilling process of offshore bored piles there are two main options to take into consideration: drilling the pile by using full guiding casing until final depth; or using a combined system of partial steel guiding casing and support drilling fluids.The knowledge and situations described in this paper come from the experience acquired in different projects where the second method was employed. This construction method consists in installing a steel guiding casing by vibration and thus covering the water table and further stabilizing the soil below it with polymeric fluids until reaching the pile’s final depth. The Fig. 1 schematic shows an example of this method where H corresponds to the length of the steel guiding casing whereas the remainder of the shaft’s length is stabilized by polymer fluid. The entire bored length is full of slurry up to top of casing.In most cases this kind of civil works results from the need to build a bridge or executing port structures in places where the creation of temporary artificial peninsulas with fill material is impracticable or not allowed. Hence the need to use floating work platforms, commonly referred to as barges."

Jan 1, 2017

The following pages discuss the objectives, the background, and scope of work of an industrial engineering analysis of far-,n haulage systems in underground retreat coal mining. This study ran concurrently with an existing industrial engineering study of methods of improving safety and production efficiency in underground pillar extraction. 1. OBJECTIVES The objective of this project was to provide basic data inputs that will inpart knowledge as to the major constraint to pillar extraction sections. Furthermore, the industrial engineering study will suggest ways to optimize haulage systems and to develop more efficient work practices and operational techniques that will maximize equipment utilization.

Jan 1, 1975

By M. E. Poad, J. K. Whyatt, T. J. Williams

Researchers at the U.S. Bureau of Mimes monitored rock mass response to mining of an experimental underhand longwall stope in Hecla Mining Co.'s Lucky Friday Mine, Mullan, ID. This stope design, the Lucky Friday underhand longwall (LFUL), was proposed as a means of controlling rock bursting while also allowing increased mechanization of mining operations. Instruments were specifically manufactured to monitor three geomechanical factors (backfill performance, ramp stability, and rock mass response) that directly affect the success of stope design. Despite considerable difficulties with instrument installation and survival in the harsh mine environment, especially within the stope fill, sufficient information was collected to suggest that the LFUL method was successful in achieving project goals. This conclusion, in addition to favorable economic and operational evidence, led the mine to adopt the method throughout the mine. Indeed, this study and mining experience suggest that underhand longwall mining could be considered a feasible mining method for rock-burst-prone ground throughout the Coeur d'Alene District. Further Reports of Investigations (RI) in this series present in-depth analyses of the effects of backfill on rock bursting and calibration of a stope numerical model.

Jan 1, 1992

Ontario Operaations Mining Garson Stobie Copper Cliff North Copper Cliff South Creighton Mcreedy East Milling Clarabelle Mill Smelting Smelter Matte Processing Anode Casting Refining Copper Cliff Nickel Refinery Port Colborne Cobalt Refinery

May 1, 2007

By Frank Cappuccitti, Stephen Chryssoulis, Stamen Dimov

Surface organic microanalysis of platinum (Pt) and palladium (Pd) minerals by TOF MS1 is an attractive complement and potential alternative to conventional collector screening methods. Its attractiveness lies on its ability to focus on individual Pt and Pd mineral particulates, therefore providing a more targeted approach. The only requirement is knowledge of the occurrence (mineral composition, grain size and association) of Pt/Pd in the feed sample. This newly developed technique can detect, and identify collectors and quantitate loadings on individual Pt/Pd mineral particulates at plant concentration levels. Using this technology, collector loadings were measured on Pt and Pd metal plates and on PtS2 and PdS particulates which had been exposed together to aqueous solutions of different collectors. Thus, data were obtained on collector selectivity, the effect of sulphur; and of depressants, the latter in combination with TOF-LIMS2 results. Staged rougher tests on North American and UG-2 ores linked Pt/Pd flotation kinetics with collector loadings and ultimately grade/recovery.

Jan 1, 2003

By Stephen C. Tadolini, Raymond A. Mazzoni

The International Ground Control Conference in Mining has always provided an open forum for the publication, presentation, discussion, and often heated debate on roof bolting systems mostly with attention to how, when, and why they work. During the last 24 Conferences at least 170 papers have been presented by International Experts on these “simple” devices that range in length from 30-inches to 20 ft and from 5/8 to 2 inches in diameter. Roof bolts are primarily mechanically anchored, glued, cemented, or driven. Bolts are placed vertically, angled, or tied together with special fixtures (trusses and slings). They have been termed active, passive, stick-slip, and several other descriptive acronyms or mining slang expressions. This retrospective paper will present the changes in bolt types and usage, point out some of the biggest myths and hail the most significant advances (according to the authors’ opinions of course).