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By W. J. Witte, M. K. Witte

"INTRODUCTION A pilot heap leach project was conducted on the B. P. Selco Hope Brook ore located in southwestern Newfoundland. The pilot heap leach was undertaken to assess and confirm the following:1) To confirm that heap leach technology now currently used in the United States could be applicable to Canadian sites.2) To confirm gold recovery by the Heap Leach technology3) To assess and study potential heap leach environmental concerns in cold and wet climate.PROJECT LOCATIONThe Hope Brook Project is located near the southern coast of the island of Newfoundland, approximately 100 kilometers southeast from Stephenville, approximately 25 kilometers west of Burgeo, Newfoundland. Access to the property is limited to helicopter, float plane or by sea through Couteau Bay. The property was covered with muskeg and very few trees. Surface relief was moderate with many poorly drained boggy sections confined to small areas. Many small unnamed lakes were located on the property which provided water to small brooks and streams flowing to Couteau Bay.Several locations were reviewed for the installation of the pilot heap leach facility. Important parameters used to select a suitable location included sufficient land area, close proximity to but not on the ore body, reasonable protection from wind, sufficient supply of fresh water, close to a suitable location for a portable crushing plant, reasonable access to aggregate material for preparation of the test pad and ponds and suitable contours to minimize site preparation."

Jan 1, 1987

"In mills, metallurgical efficiency is important in every step of the operation through to the tails. Different problems which hinder metallurgical efficiency exist in different mills. One such problem occurred in the Bralorne mill at the tailings end of the circuit, where the washing efficiency of the filters was so low that serious losses in dissolved gold occurred.The new cyanide plant at Bralorne went on stream in August 1961. Test work done showed that: a flowsheet of grinding in water, jigging, thickening, agitating, followed by double filtration, gave satisfactory results and was more economical than a counter current plant. Two filters, 141 x 161, with approximately 700 square feet of filtering surface on each, were purchased and installed in series. Test work showed that this was ample filtering area for 500 tons per day.When the plant started up a density of 45% solids was maintained in the agitators, and a 20 ounce cotton dl1ck was used on the filters. Vacuum was between 23 - 25 inches. Under these conditions the filters would not work and only picked up a very slight skim of pulp. Various speeds were experimented with, 4 minutes per revolution being the most efficient. At this speed the thickness of the pulp on the filters increased to about 1/8”• It was therefore quite apparent that, under these conditions, the filters would not handle very much tonnage and the mill tonnage would have to be reduced drastically until the problem was solved."

Jan 1, 1967

"The Kidd Creek concentrator is situated adjacent to Highway 101, twenty-four kilometres east of the center of the city of Timmins, Ontario. Sulphide ore, received by train from the minesite twenty-nine kilometres away, is processed at a rate of twelve thousand metric tonnes per day. Saleable concentrates of copper, zinc, lead and tin are produced.The concentrator contains secondary crushing, grinding, flotation, gravity separation and concentrate handling facilities. The total concentrator manpower complement is one hundred and sixty-four which includes supervision and operating personnel. Twenty-one shift personnel are required to operate the processes involved and they occupy fifteen different operating positions in addition to that of the supervisor. These positions include:1 Central Control Operatorl Metallurgical Leader1 Dryer Control Operatorl Crusher Leader3 Copper-Lead-Zinc Flotation Circuit Operators1 Pyrite Flotation Circuit Operator1 Tin Plant Operator2 Grinding Operators1 Concentrate Operator2 Crusher Operators1 Spare Operator1 Tailings Area Operator1 Automatic Sample System Operator1 Dryer Area Helper1 Crusher Helper1 Tin Plant Helper"

Jan 1, 1981

By G. E. Agar, R. Stratton-Crawley

"The applicability of a hydrocyclone model to simulation of the cyclone banks in a multi-stage sandplant circuit producing mine back fill has been demonstrated. The model ha~; been used in conjunction with a modular computer program for circuit simulation in order to study the effect of changes in the operating conditions. It has been shown that weight recovery to sand fill increases as feed percent solids decreases, and, to a lesser extent as pressure drop across the banks increases. An increase in apex diameter also causes an increase in weight recovery. Increased weight recovery must, however, be balanced against sump an1l cyclone capacity and dilution of sand fill by fines. The predicted results from circuit simulation were in good agreement with plant data.The model has been found to be applicable to widely different ores."

Jan 1, 1979

By M J. Daniel

Comminution is the science of size reduction of brittle materials. It is integral to mineral extraction and is one of the most energy intensive processes in the mining industry. There are a number of tests used to quantify the strength of ore, which are then used to size the AG / SAG mill in circuit design. The calculated energy utilized for breakage in these devices is based on the assumptions that the materials treated are of average shape and that the processing equipment is designed to break the ore as efficiently as possible under the given operating conditions. In drop weight tests, it was found that shape significantly influences the measured rock strength. Controlled experiments with variations in blends of rock shape show that mill throughput increases with the addition of weaker shaped rocks.

Jan 1, 2012

By W. S. Urbanski, A. L. Devernoe, R. W. Stuart, M. S. Walker

"Although many investigators have successfully achieved separations using variations of a concept wherein particles are buoyed upwards against gravity in a magnetically attracted fluid, none have succeeded in separating fine particles in a manner that is practical tor mineral beneficiation. This paper describes laboratory tests and preliminary economic analyses for a new mineral separation process which provides enhanced magnetic buoyancy and separation capabilities. The process provides a means of gravity separation in a regime where conventional gravity separation is inadequate; that is for small differences in mineral densities and for very fine particles. Although early interest centers on gravity separation, the process has also been successfully used for precise magnetic separation.Tests were conducted on a variety of mineral mixtures, ore samples and concentrates including; a sphalerite ore, pyrochlore ores and concentrates, cassiterite pre-concentrates, a chromite pre-concentrate, and heavy mineral placer samples. Separations requiring high discrimination between fine particles narrowly different in density or weak magnetic properties were obtained. Of particular interest is the ability of the process to concentrate or remove oxide minerals or gangues, especially silicates. Potential applications are discussed."

Jan 1, 1985

In-Country Business Development Agenda ?Siting/Permitting/Operational Planning ?Securing, maintaining, enhancing social license to operate ?Biodiversity conservation and ecosystem services ?IFC Performance Standards ?Environmental, Social, Risk Governance (ESG) ?Climate change plan

Aug 1, 2013

By R. C. Snider

The Roy Lloyd Mine in northern Saskatchewan is a high-grade underground gold mine which is currently supplying ore to Golden Band Resources Inc. (Golden Band)?s Jolu mill. Prior to the operation of the mine, an underground exploration program was conducted intermittently at the site. During both the underground exploration phase and mining, Golden Band has implemented water recycling to reduce freshwater usage within the mine in order to address concerns over the potential for impacts associated with freshwater usage and to reduce the volume of effluent discharged from the site. Golden Band initiated an underground exploration program at the Roy Lloyd Mine site (formerly called the Bingo Project) in October 2007 to better delineate the mineralization of the Bingo gold deposit. The exploration program provided geological information required in order to improve the confidence level of the geological resource model and also provided information to aid in the mining of the deposit, such as the determination of groundwater inflow rates. Underground production mining started in March 2011. This paper provides an overview of the mine water recycling methods implemented at the site during both the exploration and initial mining phases of the project, and the success/drawbacks of these measures to date, including the potential cost savings in the form of reduced treatment and monitoring costs inherent in a reduction of the volume of effluent discharged from the site. The paper will also discuss options that are currently being evaluated in order to further assist Golden Band?s ability to recycle water and reduce the volume of effluent discharged to the environment, while ensuring effluent discharged from the site to the environment meets criteria.

Nov 1, 2011

By E. Marcotte

"Technology developments and improvements are imperative to maintain a viable mineral processing industry. In order to achieve optimum implementation of technology in processing plants, safety conscious and efficient work forces are required. Effective management methods are required to prevent employee injuries, equipment or environmental damage and process losses. Good leadership also provides for employees to perform their work in the safest and most efficient manners to attain optimum recoveries of the valuable minerals and produce high quality mill products. Equipment and processes must be designed, operated and maintained as required to assure safe and efficient mineral processing.INTRODUCTIONThe Canadian mining industry must contend with many challenges to attain and maintain a competitive position in today's global market. Canadian Mineral Processors play a vital role in meeting the challenges and achieving optimum mineral productivity.Ongoing technology developments and improvements continue to be imperative to maintain a viable mineral processing industry. The efficient implementation of technology developments requires a safety conscious, skillful and productive work force.In addition to technical and human resources, challenges may also include governments, labour unions or environmental advocates who at times may appear to be misguided or unrealistic. Canadian Mineral Processors must not allow themselves to be overwhelmed by these apparent obstacles but must use their demonstrated ingenuity to achieve successful solutions.It should be recognized that the majority of the Canadian work force are, in fact, a potentially talented and skillful people with ambitions to excel. As leaders of people, we must provide the methodology, incentive and direction that will allow our work forces to realize their ambitions. If the potentials of our work forces are not recognized and leadership is not properly exercised much loss will occur. That is, safe effective and efficient work will not be achieved."

Jan 1, 1993

By M. Muinonen, A. R. Barnes, R. Pandher, M. J. Lavigne

Over the past three years, Ring of Fire chromite ores have been tested extensively at both the bench scale and pilot scale at XPS Consulting and Testwork Services. Following bench scale testwork, two smelting campaigns were completed using a 300 kW DC arc furnace on different chromite deposits from the Ring of Fire. A ChemSheet model was developed to aid in the design and optimization of the recipes, and its predictions were confirmed with both the bench scale and pilot scale tests. A total of 7.5 tonnes of chromite ore was smelted at XPS. The results of the testwork demonstrate excellent reducibility for the ores tested with good reduction kinetics when compared with South African chromites.

Jan 1, 2014

By M. Moghadami

Design and construction of underground openings are associated with many uncertainties with regard to input data. In the construction process of underground openings various levels of risks exist and these affect the safety and profitability of the project. The development of underground openings can be broadly categorized into three major phases of data collection, design, and construction. A significant level of uncertainty is associated with some of the key parameters involved in the aforementioned development phases. Moreover, it is very difficult to evaluate and quantify the effects of uncertainties on the underground project construction process. Additionally, the interactions between important risk elements are typically not well understood. The intention of this study is to develop a general risk model for underground opening projects located in soils and weak rock masses. The goal of the research is to identify and quantify important geotechnical risk elements. Moreover, a weighting procedure will be proposed for the identified risk elements. Finally, all important risk elements will be assembled into a general model with emphasis on geotechnical parameters. The final objective of this study is to apply the proposed model to a real underground project scenario and verify it for actual field conditions. The proposed model, once calibrated properly, will provide a useful support tool for the decision making process.

Aug 1, 2013

Everybody would agree that a good roadway leads to more efficient haulages by reducing haul times, smoother and safer operation for operator and less wear and tear on tires and equipment, thus improving availability and overall costs efficiency. There is a number of factors that come into play to achieve this especially when developing a mine. Excavations of Ramps and Headings: Operators should follow surveyors and layouts accurately while driving ramps. To maintain constant grades on ramps, which leads to better design control of water and easier grading of roadways. Dips and dives lead to needless over excavations and unnecessary cost and disposal of waste rock. When dressing a ramp some areas may require 2 to 3 feet of material to correct the dips and perfect to constant grade. You may ask yourself, is this all necessary? A small exercise is to follow a loaded haulage truck up ramp. At the first hump, grade change, notice the down shift and notice how far the truck travels to regain the up shift and his speed. The difference is remarkably noticeable when the grade is constant. All this leads to less driveline shock, less horsepower demand, better fuel efficiency and more productivity. Drill & Blast Patterns to control water for Ramp Headings: The drill pattern needs to allow for a ditch. A slight cross fall to form a ditch can easily be done with the lifters. The preferred side of the ditch is always the inside curve of the ramp as it has less tendency to erode roadbed material. On a level, the ditch is dictated by the sump location. A blasted ditch will eliminate water pounding and keep the roadbed dry. Water trapped in roadbed is the major cause of rollout and de-stability of roadbed. If the water is allowed to drain in the middle of the ramp it will cause erosion, movement and loss of fines and an increase in grading intervals.

Feb 1, 2008

By Kadir Sariiz

Abstract - The Akçayir-Yürükakçayir Miocene-Pliocene basin in the Central Anatolia hosts ancient lacustrine sepiolite deposits. The succession in this basin consists of conglomerate (Yürükakçayir conglomerate), clayey and silty limestone, dolomitic marl, sepiolite beds and lenses, and dolomitic limestone (Kepeztepe formation). The main impurities within the sepiolite rock are dolomite, opal-CT, calcite, smectite and feldspar as sepiolite + dolomite and sepiolite + opal-CT are the main mineral assemblages. Smectite and feldspar are thought to be of detrital origin. Calcite is found as a secondary filling in root tubes and casts. Sepiolite samples studied display root-marks and root tubes, soapy and massive structure indicating direct precipitation. Sepiolite deposits probably formed at a pH of 8 to 9, and Mg+2 and SiO2 concentrations in moderately saline environments of internal facies of an alkaline lake.

Jan 1, 2000

By Y. A. Grinin, M. A. Liamina, V. A. Shumskij, Y. I. Sannikov, M. V. Radashin

"A brief history of the development of the Kivcet flash smelting process is presented. The broad scope of the process with an ability to treat high grade lead sulphide concentrates, as well as oxidized lead-zinc residues, is emphasized. Fine coal in the charge serves two purposes, one as auxiliary fuel and the other as a pre-reductant for ferric iron in residues. Current Kivcet operations incorporate a layer of coke or “coke checker” at the surface of the slag in the reaction shaft that acts as a reducing agent for flame products or slag that flow through it. Details of this invention, are given. IntroductionFor many years, the sinter-blast furnace lead smelting process has been the main internationally accepted method used for the production of primary lead metal. In recent times, this process has been unable to meet legislated environmental restrictions and it became clear in the mid-1960s that a new and cleaner process would have to be developed. The present level of Kivcet performance was developed in three main stages:1. flash smelting natural sulphide lead raw materials with the attached electric furnace for production of lead bullion and crude zinc;2. natural raw material smelting with lead and zinc separation in a “coke filter” or “coke checker” at the surface of the slag in the reaction shaft to produce lead bullion and ZnO-bearing slag that can be fed to conventional slag fuming; and3. processing of oxidized lead-bearing raw materials, such as low grade zinc plant residues, with the production of lead bullion and ZnO-bearing slag periodically directed to slag fuming."

Jan 1, 1998

By Roger Reed

It is well known that the performance and carbon emissions associated with the modern gas turbine engine depend critically upon the properties of the nickel-based superalloys, particularly those used in single crystal form. However, the design of all alloys in current use has been essentially empirical, or at best heavily reliant upon regression/neural network analysis of experimental datasets. In this paper, alloy design approaches [1] are described which are able to identify new alloy composition spaces which are worthy of experimental study. It is shown that a large amount of design data can be generated, which can be interpreted in different ways. Of course, the success of the approach depends heavily upon the accuracy of the underlying sub-models. Estimates of the creep resistance, cost, castability, density and oxidation resistance are made. It is demonstrated that these methods allow quantitative trade-offs to be made between the properties of interest.

Jan 1, 2010

By M. R. P. Snow

"This paper outlines geotechnical conditions that commonly exist in underground, hardrock mines and the challenges posed for ground-support steel, specifically rockbolts, used in these environments. A model is proposed whereby the in-situ stress and rock-mass classifications (based on Bieniawski’s rock mass rating) form the basis of determining the desired steel properties of the rockbolts used. Based on the ASTM F432 bolting specification, recommended minimum steel properties are defined for three ranges of in-situ stress levels, each with their own six ranges of RMR values. Heat treatment for the steel can be specified once these minimum steel properties are known.RÉSUMÉ Le présent article décrit les conditions géotechniques qui existent fréquemment dans les mines souterraines de roches dures et les défis que cela pose pour le soutien de terrain en acier, plus spécifiquement les boulons d’ancrage utilisés dans ces environnements. Un modèle est proposé dans lequel les contraintes in situ et les classifications de la masse rocheuse (selon la classification de la masse rocheuse de Bieniawski) servent de base pour la détermination des propriétés désirées pour l’acier des boulons d’ancrage utilisés. En se basant sur les spécifications de boulonnage de l’ASTM F432, les propriétés minimales recommandées pour l’acier sont définies pour trois plages de niveaux de contraintes in situ, chacune avec sa propre plage de six valeurs de classification de la masse rocheuse (RMR). Un traitement thermique pour l’acier peut être spécifié une fois que ces propriétés minimales pour l’acier sont connues."

Jan 1, 2016

By Zhigao Xu, Ruan Chi, Zhenyue Zhang, Yaoyang Ruan, Zhengyan He

Weathered crust elution-deposited rare earth ore is a specific rare earth resource in China that is rich in middle and heavy rare earths. From surface to bottom, the weathered crust elution-deposit rare earth ores can be divided into humic layer, completely weathered layer, partly weathered layer, and bedrock. The exchangeable rare earth ions mainly exist in the completely weathered layer and partly weathered layer, and the exchangeable aluminum ions mainly exist in the humic layer. A novel solution injection method for use in the in-situ leaching technology of weathered crust elution-deposit rare earth ores was put forward based on the different distributions of RE3+ and Al3+ in the four layers. Avoiding the humic layer, only the completely weathered layer and partly weathered layer were leached by controlling the height of the leaching solution liquid level. In this way aluminum, the primary impurity in the RE leaching solution, can be decreased and the purity of the RE product can be improved. Meanwhile, the choices of available leaching reagents were broadened and the possibility of landslide disasters could be reduced.

Jan 1, 2014

By Gordon. I. M., J. Blackshaw

"The wet part of the Hollinger mill is housed in two buildings, the grinding plant and the treatment plant. In the grinding plant there are four 7xl5 ball mills which grind the ore to 60 per cent through 200 mesh. There is also one 7xl5 ball mill which grinds table concentrate to 9 5 per cent through 200 mesh.The primary classifier overflow is pumped to the treatment plant where it passes over shaking tables, producing a concentrate and a tail. The concentrate pulp is pumped to the grinding plant for secondary grinding. The secondary classifier overflow is pumped back to the treatment plant where it is thickened in two 40xl 5 tray thickeners and agitated in four 20x24 mechanical agitators arranged in series of two (with 2 spares).The table tail pulp is thickened in nine primary 40xl5 tray thickeners (with 2 spares). The thickened table tail pulp and the concentrate agitator discharge pulp are mixed and pumped to four rows of 15x45 pachuca agitators, arranged in series of five tanks.The pachuca discharge pulp is divided. The smaller part goes to two rows of 3-step decantation using 40xl5 tray thickeners (with 2 spare rows). The larger part goes to six 14xl6 drum filters. The repulped primary filter cake and the thickened pulp discharged from the decantation rows are fed to eight 14xl6 drum filters. The secondary filter cake is mixed with water and pumped to the tailing line."

Jan 1, 1968

By Jason Prno

Context ? Climate change an issue of global significance ? Research is lacking ? Study initiated by the David Suzuki Foundation, led by ArcticNorth Consulting Industry Surveying ? 34% and 48% of respondents indicated climate change is already affecting operations ? Majority believed climate change would have negative impacts in the future ? Cost and uncertainty of Future impacts are major barriers to adaptation

May 1, 2010

By D. Houghton

"I am very pleased to be a member on this panel today because abrasion and wear in mills has been part of my life over the past forty years. My presentation will deal with the role Ni-Hard has played in combating wear and abrasion in mills. Before Ni-Hard came along, unalloyed white iron was used in ball mills and one of the most popular types of white iron liners was the pocket liner. Slide #1 illustrates the design of the pocket liner used at Dome Mines in their 5' x 22' pebble mills. The pockets filled with grinding media and it was on this that the wear took place. The concept is not unlike the new magnetic liner which utilizes the ore and grinding media to form the wearing surface. In this slide please note the tapered pocket type of cored bolt holes. If cored bolt holes do not fill with grinding media there could be excessive grooving or wear at that area. Therefore all cored bolt holes should be tapered in this manner.Before Inco patented the name Ni-Hard several foundries were making the alloy iron under different brand names such as Diamond Alloy, Mitchelloy and Specialloy. In the early days some of the Ni-Hard was poor quality. Inco provided foundries with technical knowhow and provided assistance to licence them to sell under the name of Ni-Hard. This was in the late 1920's. The material we are discussing is Ni-Hard type I with the following analysis (slide #2). It is a martensitic white iron with BHN of 550 - 600 and is a relatively easy alloy to produce in either a cupola or electric furnace. The annual average production of Ni-Hard in North America is 90,000 tons with mill liners making up 25,000 tons and grinding media 30,000 tons, according to Warren Spear of Inco."

Jan 1, 1983