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By Marko Lampi, Ross Andrews, Jouni Pihlasalo, Robert Matusewicz

With widespread discussion on reducing carbon, sulphur and other emissions, use of sustainable energy sources and the pivotal circular economy theme, consideration needs to be given to pyrometallurgical operations broadly and more specifically, non-ferrous metallurgy. These themes present a number of challenges in terms of current operations and the view of processing the metals which are largely taken for granted in day to day living. This paper considers how these themes will impact pyrometallurgical flowsheets using the non-ferrous base metals as an example. It will examine the flowsheet chain to offer views on the boundaries of flowsheet optimization and the application of available tools to meet these future goals and challenges. INTRODUCTION The themes of reducing footprint through lowered CO2, S and other emissions, together with process sustainability (e.g. lowered energy) and links to the circular economy are well known to everyone in the metals industries. Whether it is reducing greenhouse gas emissions or analysing the importance of metals recycling in the circular economy, all these themes carry with them the fundamental premise of any change being considered; how can you best optimize a system to meet your aims? Of course, this depends on the available tools and the approach used for optimisation.

Jan 1, 2019

By Mitchell Gordon

"In almost all thickener applications the highest possible solid/liquid separation efficiency is what is desired by the user. There is a trend in the industry due to monetary restraints and environmental pressures to look at ways to extract this maximum performance by either retrofitting existing thickeners or installing the most cost effective new thickener. This paper looks at some of the common problem areas and presents a range of solutions developed by Outokumpu Mintec in North America and outokumpu's subsidiary Supaflo Technologies Pty. Ltd.The Emerging PictureAfter many hours of discussions with a large number of plant personnel over the last two years a picture began to emerge regarding current thickening operations in the industry. Initially, it seemed that everybody had their own unique process problems and therefore needed a correspondingly unique solution. Looking more closely at all the cases and the ideas that we had either implemented or suggested, it gradually became apparent that the majority of operators all had one and the same process need ....""Better Separation Efficiency""The range of operational problems that were uncovered in the survey were much more varied than expected and often were not even considered initially to be thickener problems. Often, it was only after the rejection of many solutions to the problem, generally due to capital cost, that the actual cause of the problem was looked at and found to be a thick-ener.A summary of the problems that have so far been identified is presented in Table 1. They are subdivided under three major categories of environmental, process and paste fill to highlight the wide range of mining activities that can be affected by poor thickener performance. These seem to be the major areas where the need for better separation efficiency is rooted."

Jan 1, 1995

By A. J. Hyett, N. Hedrick, J. Blackall

The Garford bulb anchor is a modified cable geometry developed and patented by Garford Ply Ltd. of Australia, and which has recently become widely available in Canada. It is produced by deforming the seven wires (including the central kingwire) of a standard cable into a bulb" (Fig. 1). Laboratory cable pull tests indicate that the bond capacity of the 25 mm Garford bulb anchor is comparable to the nutcase cable, in excess of the birdcage cable, and significantly higher than standard 7-wire strand. Its comparative advantage over the latter is most significant for tests at low radial confinement and high water:cement ratio grout, which corresponds to operational conditions of low quality rock (i.e. weak, highly fractured rock masses, foliated hanging walls, failed ground, etc.) and poor installation quality control (perhaps the most common explanation for cable bolt failures). It is under such conditions that cable bolting is often ineffective. The most impressive result is that for a reduction of the effective rock mass modulus by a factor of five, the Garford bulb cable capacity remains virtually unchanged.

Jan 1, 1995

By Wouter Bleeker, Isabelle Cadieux

"Abstracts of theses related to mineral deposit studies and exploration, completed at geology or earth science departments of Canadian universities, have been compiled for the period 1991 to mid-I993. Part I, presented in the June, 1994 issue of the ClM Bulletin, gave a listing of thesis titles. Part II, which consists of edited abstracts of theses considered to be of direct application to mineral deposit studies and exploration, is presented under various themes as follows:A. Kimberlites, Other Alkaline Intrusions and Related Studies;B. Volcanogenic Massive Sulphide Deposits and Related Studies;C. Mineral Economics;D. Mesothermal Gold Deposits, Other Gold Deposits and Related Studies;E. Magmatic Nickel-Copper, Platinum Group Element, and Chromite Deposits and Miscellaneous Platinum Group-related Studies;F. Granite and Pegmatite-related Deposits and Porphyry Deposits;G. Diverse Hydrothermal Deposits. Sediment-hosted CopperDeposits and Mississippi Valley Type Lead-Zinc Deposits; andH. UranitnlHeiated studies, Evaporites and Exploration Geophysics.Abstracts related to themes A to D were presented in previous issues of the ClM Bulletin, abstracts related to themes E and F are presented in this issue. The remaining abstracts will be presented in a future issue."

Jan 1, 1994

By R. Prioul, J. Kear, D. Chuprakov, A. P. Bunger

"Hydraulic fracture (HF) growth through naturally fractured rocks challenges the development of accurate predictive HF models. The authors present laboratory experiments differentiating behaviours associated with orthogonal and oblique intersections between HFs and natural fractures (NFs). HFs were created in sandstone and crystalline (gabbro) rock specimens, impinging orthogonally or obliquely on an unbonded machined frictional interface. Ultrasound monitoring was used to observe the rate of propagation through the interface. A contrast was observed between direct and offset crossing for orthogonal and oblique intersection, respectively. The stresses required to promote crossing depended on the intersection angle between HFs and NFs.RÉSUMÉ La propagation des fractures hydrauliques (FH) dans les roches naturellement fracturées pose un défi pour le développement de modèles prédictifs. Nous présentons des essais en laboratoire qui différencient les comportements associés aux intersections orthogonales et obliques entre les FH et les fractures naturelles. Des FH ont été créées dans des spécimens de grès et de roches cristallines (gabbro), heurtés de manière orthogonale ou oblique sur une interface machinée, non liée, de frottement. Un suivi par ultrasons a servi à observer le taux de propagation à travers l’interface. Un contraste a été observé entre un croisement direct et un croisement indirect des intersections respectivement orthogonales et obliques. Les contraintes requises pour promouvoir le croisement variaient selon l’angle d’intersection entre les FH et les fractures naturelles."

Jan 1, 2016

By François Robert, Rex Brommecker, Don S. Bubar

"The Orenada Zone 4 deposit is a small vein-type gold deposit occurring directly within the Cadillac Break southeast of Val d' Or in southeastern Abitibi Sub province. Mineralization is hosted by the Piche Group which, on the Orenada property, consists of talcchlorite- carbonate, chlorite-carbonate, and sericite-chlorite schists, derived from ultramafic volcanic, mafic igneous, and intermediate to felsic volcaniclastic rocks, respectively. All these rocks have been carbonatized.Rocks of the Pichi Group display a strong east-west, subvertical S1foliation, which is superimposed by asymmetric, intrafolial F2folds with shallow to moderate plunge to the east and to the west. F2folds are accompanied by an S2, subvertical axial planar cleavage, and are interpreted to result from dextral transcurrent shearing along sr.The Zone 4 deposit occurs within a large F2 fold, 60 m wide and plunging at 45 to the east, down to a depth of at least 300m. The auriferous zones consist essentially of zones of closely spaced, parallel quartz-tourmaline-albite-carbonate-arsenopyrite veins concordant to Sr these veins have been folded by the large F2fold and may pre-date the folding. A few discordant quartz-tourmaline-arsenopyrite veins, post- dating the F2 folding, also contain gold. Wallrocks adjacent to concordant veins have been carbonatized, albitized and contain significant amounts of tourmaline and arsenopyrite, with which gold is intimately associated.The Orenada Zone 4 deposit is a unique example of a deformed vein- type gold deposit, and exemplifies one of several types of association of lode gold deposits with folds."

Jan 1, 1990

By D. A. Bordin, C. J. Newman, R. J. St. Eloi

"The requirements for a metallurgical acid plant treating smelter gases are both unique and demanding in terms of sulphur dioxide treatment and emission control. Since start up in 1981, the copper smelter at the Kidd Creek Division of Falconbridge Limited has undergone several major expansions. The expansion and modification of the acid plant has been an integral part of this process. Both production demands and government regulations dictate that this metallurgical acid plant be unique in terms of operating flexibility. The variable capacity to treat a wide range of sulphur dioxide concentrations, and the operating flexibility to control emissions are the topics of this paper.INTRODUCTIONThe Kidd Creek Division of Falconbridge Limitied is a base metal mining and metallurgical complex located in Timmins, Ontario. The discovery of the original copper-zinc-silver orebody was announced in April, 1964. Mining operations began in 1966 with a 9000 tonne per day concentrator coming on stream in November of that year. In April 1972, a 108 000 tonne per year zinc plant was commissioned. Over the years the facilities have been expanded, such that the concentrator now has the capacity to process 13 000 tonnes of ore per day . To expand zinc production, the world's second installation of the Cominco/Sherritt pressure leaching facility was completed in 1983 to bring total zinc production capacity to 125 000 tonnes per year. In 1973, serious planning for a smelter operation began. In early 1975, after studying both continuous smelting and flash smelting processes, a decision was made to proceed with the technology offered by Mitsubishi Metal Corporation of Japan. The Mitsubishi Continuous Smelting Process was to be used for the smelter and the Onahama No.3 tankhouse technology for the copper refinery.The smelter, which uses the Mitsubishi Continuous Smelting Process for the continuous production of blister copper from concentrate, went on line in June 1981. It has been expanded from its original capacity of 60 000 tonnes to 100 000 tonnes per year of copper.From the very early design stages for the metallurgical complex, the company had adopted a policy of constructing and operating modern plants which would meet existing and anticipated environmental standards. With this in mind, the decision was made to utilize the proven technology of fixing sulphur dioxide emissions, in the form of sulphuric acid. A 636 tonne per day single absorption contact acid plant was built to serve the zinc plant in 1972. In 1981, an 883 tonne per day double absorption contact plant was built to serve the needs of the copper smelter. The copper smelter acid plant has since been expanded to a design capacity of 1692 tonnes per day and it is the main focus of this paper."

Jan 1, 1989

By Maureen A. McGuinness

Kidd Mine, an Xstrata Copper operation in Timmins, Ontario, operates a 400 t/h pastefill plant that provides paste backfill to stopes at the depth of 9000 ft. This paper will cover the operating practices of the pastefill plant both on surface and underground, highlighting tailings excavation, paste mix design and the pipe maintenance program. Kidd Mine, une opération d'Xstrata Copper à Timmins, Ontario, opère une usine de remblai d'une capacité de 400 t/h. Le réseau de distribution permet d'acheminer le remblai en pâte juste qu'à une profondeur de 9000 pi. Cet article couvrira le mode opératoire de l'usine de remblai tant à la surface que sous-terre en mettant l'emphase sur l'extraction des rejets miniers, la recette du remblai en pâte ainsi que le programme d'entretient du réseau de distribution.

Feb 1, 2008

By Masaharu Moteki

At present, the Unmanned Construction System (UCS) is adapted on initial operation against the disaster. For instance, it has been used in Unzen. When the scale of the disaster is big, or the danger to a person is big, the UCS is expected as a quick and safe construction technology. The Remote Controlled UCS is introduced into construction site to repair earth-fill embankment or to remove rock, as urgent measures after the disaster outbreak. For improvement of the operability, shortening of the skill time, reduction of the fatigue, examination of the most suitable system (placement of a monitor and the joy stick) of the remote system is a main theme in the Public Works Research Institute (PWRI). In the report of this year, when the operator controls construction machine directly or he controls it using remote system (he can check the situation of site only via monitor), the degree of achievement, construction efficiency and construction precision were inspected. The remote system which is based on the system used at Unzen was developed at PWRI.

Aug 1, 2013

This paper generalizes open stopes into elliptical cross sections and applies the results of calculations based on the mathematical theory of elasticity to indicate stress distribution on the boundaries of such stopes. These show both compressive and tensile stresses and provide an ex-planation for the development of excessive dilution in shrinkage toping. Introduction T HE stress pattern around shrinkage stopes is identical with that around other stopes under the same physical conditions. However, a shrinkage stope ends as an unsupported open stope, and the method i limited to the stress range within which the rock is generally self-supporting. If it is acceptable to generalize the outline of a shrinkage stope into an elliptical cross section, then the graphs of Geldart & Udd (1) (see also Panek (2) and Denkhaus (3)) provide a good base for approximating the stress distribution as mining progresses. However, with failure conditions in the walls, the axis ratio, as cut

Jan 1, 1964

By D. Bai, F. Hamad, S. Abraham

For the integrity of welded structures such as pipelines, the toughness of the heat-affected zones (HAZ) is an important property. This property is often specified in terms of Charpy V-notch (CVN) impact toughness and determined by the standard test method. An experimental study has been conducted in an industrial laboratory to measure the impact toughness of the coarse grain heat-affected zones (CGHAZ) of an X80 line pipe material. The field girth welding conditions in terms of heat input were simulated, together with special edge preparation to improve the targeted testing of the CGHAZ. The effect of toughness of the neighboring regions, in particular the weld metal, on measured impact toughness of the CGHAZ was investigated. The fracture paths of the CVN tested samples were examined by both optical and scanning electron microscopy. The deviation of segments of the fracture path into the weld metal was found to have a significant effect on the measured impact toughness of the CGHAZ.

Jan 1, 2005

By Audrey Wagenaar

Introduction ?? Rising public pressures are being placed on companies worldwide to protect the environment and the health and safety of their workers and local communities. ?? International bodies and shareholders want to make sure developments and companies can meet internationally acceptable standards for EHS. In 2005, Golder Associates was asked by the IFC to conduct a comprehensive review and update for their Environmental Health & Safety Guidelines including the mining sector.

May 1, 2008

By J. W. Scott, G. G. R. Falkenberg

"The Syncrude project is an integrated complex designed to mine, extract and upgrade bitumen from the Athabasca tar sands to produce 129,000 barrels per day of synthetic crude oil. This paper provides a brief general description of the location, history and geology of the tar sands and the overall organization and structure of the project. The major emphasis and the bulk of the detail presented deals with the extraction plant; a material handling and mineral processing installation designed to treat 312,000 tons per day of tar sand feed.History of the Tar SandsThe Athabasca tar sand deposit was recorded in 1788 by Peter Pond, however the first serious geological mapping and exploration did not begin until 1915. Little interest was taken in the deposits until the Second World War, when the governments of Canada and Alberta conducted an extensive exploration program. In addition a number of pilot plants were sponsored during the 1940 -1950 decade. The hot water separation process was successfully demonstrated on the pilot plant scale during 1948 -49, and was established commercially in 1967 in the G.C.O.S. plant. The Syncrude plant, due to come on stream in April 1978, also employs the hot water separation process."

Jan 1, 1978

By X. J. Guo, H. X. Li

The biological heap leaching at Zijin copper mine is currently the largest industrial application of biohydrometallurgy and one of the earliest mines to develop biological metallurgy technology in China. Since 2001, through demonstration plant and different expansion stages, it has been developed to produce 20,000 tons cathode copper annually. However the ore grade of heap leaching gradually decline year by year with copper grade average at around 0.23% now. The copper mineral is mainly the secondary copper sulfide, and symbiosis with higher content pyrite, the sulfur and iron contents is about 15 times as copper in the ore (S/Cu>15), so the acid and iron treatment of leachate, extractant and acid mine waste water is a great challenge. Combined with located in the rainy area of southern China, huge amounts of over 10 million cubic meters acid drainage need to be treated every year, so the recovery of copper from waste water as well as low grade ore is one of the characteristics of this process. This paper in general introduced the operation of heap leaching, solvent extraction, stripping and electrowinning process in Zijin mine, summarized the experience of production and technical practice, and discussed the methods of heap construction, leaching rate enhancement, third phase formation and treatment, mine effluent treatment, resource recovery and heap slope reclamation. INTRODUCTION The Zijinshan gold and copper mine is located in southeast China, Fujian province, and the typical distribution characteristics of gold and copper deposit are "upper gold and lower copper", both are large porphyry deposits. By the end of 2017, the accumulated proven reserves of available gold resources were 318 tons, copper are 2.15 million tons, and the prospective reserves of copper are more than 5 million tons. The gold mining is open pit while the copper mining is open pit and underground. The cut-off grade of gold mining is 0.15 g/t, and that of copper mining is 0.15%. A large number of very low-grade gold ores (grade <0.30 g/t) adopt a combined ore-dressing process of “partial crushing/ore washing/reprocessing/heap leaching (overlying)/ carbon slurry" independently developed, while flotation and bio-heap leaching are adopted for copper mine. Among them, copper ore with more than 0.25% copper content enters the flotation system to produce copper concentrate, while that of less than 0.25% copper content is processed by bio-heap leaching, solvent extraction and electrowinning. Zijin biological heap leaching plant is the first mine in China to achieve the scale of annual output of ten thousand tons of cathode copper since 2006. In 2008, the solvent extraction and electrowinning system were expanded, now with a daily processing capacity of 20,000 tons of ores, an annual output of 20,000 tons of cathode copper, the expanded plant is the largest biohydrometallurgy plant in China.

Jan 1, 2019

By J. Locat, G. Parker, D. Turmel

ABSTRACT Since 1964, the Iron Ore Company of Canada has deposited iron ore tailings into Wabush Lake in western Labrador, Canada. From 1999 to 2008, the authors completed multibeam bathymetric and sampling surveys and an airborne LiDAR survey. These data were integrated to study the evolution of the tailings delta shoreline and lakebed elevation. Subaqueous channels evolved between surveys, influencing the tailings depositional pattern. With this analysis it is possible to evaluate the effect of disposal strategies on the delta topset and tailings accumulation. This project uniquely couples marine and terrestrial techniques to follow the fate of tailings in a dispersal system.

Jan 1, 2014

By John Keay, Douglas R. Shaw, Gregory J. Olson

"The results are presented herein of on-going laboratory investigations of heap bacterial oxidation as a pretreatment method for the recovery of sulfide-encapsulated gold from ore samples of the Rhodes Mining Lahoca deposit, located in northern Hungary. The ore contains just over 2 g Ault and as much as 6% sulfide, mostly as pyrite. Laboratory aerated column tests conducted at Colorado Minerals Research Institute (CMRI) showed that mild to moderate biooxidation of the finely crushed ore occurred rapidly in approximately three months, with cyanide gold recoveries of up to approximately 60%. The results contrast cyanide gold recoveries of less than 30% from non-pretreated ore. Mineralogical examination of biooxidized residues indicated that the mechanism of biooxidation of crushed ore was related to microorganisms following pathways along structural anomalies in the pyrite grains. Such selective biooxidation is an important result to minimize the biooxidation and aeration time and effluent neutralization costs in a commercial operation.IntroductionThis paper describes the development of a heap biooxidation process for the Lahoca gold project The Lahoca deposit is situated in northern Hungary, at the site of a former copper mining area. Lahoca is a large tonnage, relatively shallow, deposit amenable to open-pit mining Lahoca has the potential to produce I 00,000 ounces of gold annually for at least ten years at its minimum reserve base.The laboratory test work conducted initially by Rhodes Mining NL demonstrated that the Lahoca refractory ore is amenable to whole ore and concentrate oxidative pretreatment and cyanidation. Capital and operating costs, however, for such milled ore treatments were considered relatively high. Rhodes Mining subsequently evaluated heap leaching methods, particularly heap biooxidation pretreatment, as a process route that promised superior economics suitable for exploiting lower gold grade refractory ores.This paper focuses on the laboratory column (simulated-heap) biooxidation test work, particularly the proposed mechanism of selective microbial oxidation, wherein only a small amount of the sulfides are oxidized sufficient to allow commercially acceptable gold recoveries by conventional cyanide heap leaching. Selective or minimal biooxidation of sulfides is considered important to minimize biooxidation time and aeration requirements, as well as acid effluent neutralization costs."

Jan 1, 1998

By F. Boudreault, C. Hendricks, M. Scobie

Drilling accuracy represents an important quality control factor in minimizing dilution. Apart from geology, the factors governing drilling accuracy are largely within the control of the mine. Setup location and alignment, as well as actual drilling accuracy, can all be monitored toward their improved control. Trajectory deviation during drilling, although usually beyond the control of even the most experienced and conscientious driller, can be accounted for (if not full controlled) by down-hole surveying of blastholes prior to explosives loading. This paper reviews the available instrumentation for improved drill setup and recent field experience with several commercial systems designed for monitoring borehole deviation. It reports on a recent survey of 50 Canadian mines which use blasthole stoping and addresses the reasons for the apparent lack of interest in instrumentation: i.e. does this reflect a lack of awareness of the technology, perceived inadequacies in its performance or a predominant reliance on productivity (drilling and mucking) as a measure of operational efficiency? The survey findings supported the latter viewpoint and showed that very few Canadian mines operate drilling incentive programs that are related to drilling accuracy.

Jan 1, 1994

Fiabilité Totale d?Usine (FTU) Plan de la présentation ?Théorie de l?entretien ?Analyse comparative juin 2005 ?Session de travail 2005-2006 ?Suiviet Résultats(IndicateursdePerformance)

Feb 1, 2008

By Dwayne D. Tannant

The Fox Pit at EKATI Diamond Mine reached a depth of approximately 150 m as of September 2005. The pit is designed with 11 m wide benches excavated using a double benching technique leaving 30 m high bench faces. A series of blasting tests were conducted to improve catch bench reliability and increase the percentage of benches that meet an 11 m catch width. The design changes focussed on reducing damage to the bench crest because maintaining the bench crests is the most important factor in achieving good bench reliability. The most significant improvement was obtained by raising the bottoms of the lower trim blastholes by 0.5 m. This change decreases the depth of broken rock below the final bench elevation, and consequently reduces damage to rock that forms the bench crest below. Another improvement was the use of smaller diameter (165 mm vs. 270 mm) blastholes in the A and B rows for the upper trim blast. This change reduces the charge per delay during detonation, reduces the powder factor slightly, and reduces the energy affecting the final pit wall and crest. As mining and the blast testing progressed, the portion of the bench with crest achievements (>11 m) increased from 57% to 75%.

May 1, 2006

TIPS FOR SUCCESSFUL WASTE MANAGEMENT ? WASTE MANAGEMENT PLANS ? Define the question to be asked in waste characterization studies ? Calibrate assessments and designs with field conditions ? Ensure consistent with short, medium and long-term mine plans ? Design robust plans - goalposts and expectations will change ? Fully assess and integrate costs into economic models ? Integrate waste specialists into the feasibility and design teams ? Keep it simple and when you can?t, communicate it in simple terms ? PLAN EXECUTION ? Integrate the waste management plan into daily mine operations ? Identify the critical KPI?s , track them and set clear action triggers ? Know the difference between knowledge and data ?make sure you retain knowledge and document the important Maintain management, engineering and operational focus through the mine life

May 1, 2010