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By G. R. McMeekin

"THE TOPIC suggested for my contribution to this Symposium was ""Lead-Zinc Smelting - 40 Years of Pollution Control"". The history of the development of smelting industry at Trail and the control of sulphur dioxide could make quite an interesting historical study. However, in the field of environmental control, the public is not particularly interested in what you did yesterday, but rather what you are doing today and what you are planning to do tomorrow. I can't fault this approach, but because there are some subject lessons that history can demonstrate, I would like to tell enough of the story (under three headings) to bring a focus on matters of contemporary concern in regard to public relations and ecology. The three general headings suggested are: (1) time before the capture of by-product sulphur; (2) the capture of sulphur; and (3) the ecological and public relations conclusions from these."

Jan 1, 1972

By J M. Anderson

The cable belt conveyor installation at Craigmont Mines Limited, Merritt, B.C., has the greatest one-stage vertical fall of any conveyor installed overland in Canada. Since the late summer of 1961, this conveyor has carried more than 5,000,000 tons of copper ore from open pit to concentrator site. When the conveyor is loaded, the drive motor acts as an induction generator, delivering power to an external circuit. This paper covers the selection, the operation, the performance statistics, and the installation and operating costs of this conveyor system. Introduction T HE Craigmont mine is located in the south-western interior region of the Province of British Columbia, approximately 240 miles northeast of Vancouver. A moderate climate, good roads, service by the Canadian Pacific Railroad, power from the British Columbia Hydro Authority, gas from the nearby main line of the Inland Natural Gas Company and close proximity to the village of Merritt provide a favourable location for this mining operation. The ore occurrences at Craigmont have a vertical extent of 1,500 feet,

Jan 1, 1965

By François Robert, Steve Green, Tyson Birkett, Dan Richardson

Abstract -Detailed sampling using a portable diamond drill, and interlaboratory comparison of selected samples have been combined with statistical studies of truncated populations to establish the gold content of several outcrops in the Val d'Or area. The outcrops chosen are non-mineralized. The background gold concentration in the rocks of the region is 5 ppb or Jess. Gold is distributed relatively homogeneously within the outcrops studied except for slightly increased concentrations within quartz-tourmaline veinlets. Three samples, of which 20 grams of powder are analyzed for each, can adequately determine the gold concentration of a structurally simple outcrop in the Val d'Or area.

Jan 1, 1992

By M. J. Fairweather

"The nature of minor element values and impurities are important both in the assessment of new properties and in the continuing improvement of operating plants. Impurity elements are frequently present as fixed solid solution impurities in association with the constituent minerals of a deposit or process streams in a concentrator. This paper uses five case studies to illustrate the application of simple regression analysis to the evaluation of minor element distribution in both operating mines and new deposits using analytical information readily available. This information maybe used to determine opportunities for improvements to the performance of an operating mine, to the economic assessment of anew deposit, or to the subsequent planning of an experimental study.IntroductionThe nature of minor element values and impurities are important, both in the assessment of new properties and in the continuing improvement of operating plants. Minor element values often contribute appreciable incremental revenue to a complex base metal deposit. Examples of valuable elements include precious metals, but may also include elements such as indium and bismuth which can be recovered at a profit by smelters provided with the necessary recovery circuits. During preliminary metallurgical studies of a new property there is usually a strong incentive to maximize the recovery of such valuable by-product elements. For example, the extent to which the by-product gold in a porphyry copper deposit is associated with chalcopyrite rather than pyrite may determine theeconomics of developing a new property.The nature of impurity elements in base metal concentrates is correspondingly important in minimizing the penalties which may be imposed by smelters in the treatment of such concentrates. Penalty elements include silica, dolomite (magnesia), arsenic, antimony, mercury, nickel and cobalt. The mineralogical association of these minor elements determines the ability of the mine to remove them in the concentrating process. This paper discusses means of assessing the mineralogical nature of such impurities without the use of sophisticated micro-analytical techniques."

Jan 1, 1997

By A. Longval, Q. Jiao, T. Shannon

In 2000, Xstrata Zinc (former Falconbridge Ltd.) Brunswick Smelter commissioned a modified lead blast furnace. Since then, efforts have been made to improve its operation in order to achieve optimal operation in terms of coke consumption, lead loss to slag, and improved environmental and hygiene conditions. This paper will review the important step changes in operational philosophy, undertaken since 2004, for the control of the blast rate, oxygen enrichment in blast, slag chemistry and charge level. Furthermore, a review of the improvements made in secondary materials consumed at the blast furnace will be made. This paper will also discuss the significant reduction of the frequency of accretion removal as a result of improved furnace operation.

Jan 1, 2008

By S. Perez

Core drilling is a fundamental process in the mineral exploration industry. As deep exploration in hard rocks is accelerated due to the depletion of near ground mineral resources, deep-drilling operations need to reduce their reliance in operators experience and begin to implement new technologies in order to increase efficiency and cost-effectiveness of the overall process. Currently, lack of real-time information on the bit/rock interaction is a major problem. Therefore the mechanism behind the acoustic emission, which is a proven technique for remote monitoring, generation in mechanical rock cutting must be understood in order to provide real time information about the rock. This paper aims to identify the influence of mineral composition of granitic rocks on the acoustic emission (AE) during rock abrasivity test with a single contact tool and to evaluate the feasibility of AE as a means to infer Cerchar Abrasivity Index (CAI). Single contact tool will provide precise and accurate description of the source of AE. To provide constant grooving speed Cerchar apparatus was modified to monitor AE during rock/tool interaction. Tests on the modified Cerchar apparatus are carried out under the static load of 70N and cutting speed of 1 mm/s. A Scanning Electron Microscope (SEM) is utilized to visualize the groove in the rock and to identify the mineral composition through Back-Scattered Electrons (BSE) reflected from the rock sample. Based on the microscope images, it was found that biotite shows a larger groove area and plate-like fractures accompanied with burst-type AE signal, whereas plagioclase and quartz, which are characterized by similar hardness and BSE brightness, possess shattered-like fractures and more continuous-type AE signals. In addition, a-value of the Gutenberg-Richter scale has been found to well correlate with Cerchar Abrasivity Index (CAI).

Jan 1, 2015

By Douglas R. Schmitt

In general, knowledge of the state of stress within the Antarctic lithosphere remains largely unconstrained due in part to Antarctica?s inaccessibility and because of the paucity of seismic focal mechanism solutions. As such, an important component of the ANDRILL project was to acquire new information on the stress directions and magnitudes within the upper crust. Extensive fracture mapping of the core and oriented ultrasonic televiewer logging were carried out to provide strong constraints on both stress orientations and the faulting regime. The first hydraulic fracturing stress determinations in Antarctica were also carried out to provide complimentary stress magnitudes. These measurements were accomplished using a wire-line transported hydraulic fracturing system consisting, essentially, of two synthetic polymer packers that were inflated to isolate the 1-m long pressurization interval. The tests were conducted at the end of the drilling and logging in a ~130-m section specially drilled below 1000 mbsf (nearly 1500 m from the rig floor) for hydraulic fractures. This zone was drilled primarily through competent, dense, and low permeability diamicts. The core fracture and televiewer logging information was used to site twenty separate measurements. Classic hydraulic fracturing pressurization records with unambiguous breakdown and fracture closure pressures were obtained in about half of the measurements. The remaining tests provided fracture propagation and closure pressures that are consistent with the classic breakdown curves, but they did not include a clear breakdown pressure and are indicative of the reopening of either natural or drilling induced fractures in the wellbore wall. The preliminary analysis of the results are in generally good agreement with the stress directions indicated by the core fracture logging and the stress regime suggested by the character of the drilling induced core fractures.

Jun 1, 2012

By Dao Dac Tao

The Vietnam coal industry in recent years has achieved the rapid growth. However, in the process of industrialization and modernization of the country, the demand for coal for energy is constantly increasing. This paper presents the Vietnam coal industry in the last stage: the opportunities and challenges facing the coal industry as it strives to become modern, highly effective and capable of meeting the demands of national energy security, all in harmony with socio-economic and environmental needs.

Aug 1, 2013

By J. Warner, K. A. Hughes, P. E. R. Blanchard, J. Esslifie-Dughan, J. W. Reid

Tailings management plays an important role in reducing the environmental impact of Orano Canada’s uranium mining operations in Northern Saskatchewan. Uranium ores mined from Northern Saskatchewan are often associated with large amounts (10-20 wt%) of other harmful elements, such as arsenic and nickel. The JEB Tailings Management Facility (TMF) located at McClean Lake, Saskatchewan is designed to prevent potentially harmful water-soluble elements, particularly arsenic, from contaminating the surrounding environment by promoting the formation of water-insoluble minerals. It is therefore important to determine which arsenic-containing mineral species are present in the TMF and how they evolve over time. Researchers at the Canadian Light Source (Saskatoon, Saskatchewan) were successful in identifying the arsenic mineral species present in tailings samples collected from the TMF in 2013 using X-ray absorption near-edge structure (XANES) spectroscopy. XANES analysis verified that the majority of arsenic species in the TMF existed as amorphous and crystalline ferric arsenates with minor amounts of arsenite and arsenide species. Herein, XANES is again used to analyze a new set of tailings samples collected from the TMF in 2018, specifically focusing on the difference in the distribution of arsenic species in old and new tailings.

Jan 1, 2020

By S. Harvey

The McArthur River deposit is a structurally-controlled unconformity-related uranium deposit. The mineralization is situated at the intersection of a pronounced fault zone, referred to as the P2 fault zone, and the unconformity between Paleoproterozoic Wollaston Group metasedimentary rock and Paleoproterozoic to Mesoproterozoic Athabasca Group. Mineralization is variably hosted within the Athabasca Group fault wedge and the faulted basement, consisting of twelve zones covering a strike length of 2,700 m. The main P2 fault zone consists of several reactivated foliation-parallel faults containing narrow seams of graphitic clay gouge that are separated by highly cleaved, graphitic wall rock. The mine grid east-dipping P2 fault zone is characterized by reverse offset of the unconformity surface. It varies from a single discrete fault to splay offsets consisting of two to three individual splays. The combined vertical offset along the P2 fault zone is a maximum of about 80 m. The fault has emplaced a wedge-shaped sequence of Wollaston Group metasedimentary rocks into the Athabasca Group. Foliation-oblique faults occur throughout the McArthur deposit trend. Steep east-northeast trending faults generally exhibit apparent oblique dextral sense of shear. Less common, and possibly conjugate, are steep faults trending east-southeast with an apparent sinistral sense of shear. Offsets are generally less than 10 m on these structures. South-trending and shallow west-dipping brittle faults with offsets less than 1 m are also observed while rare steep, north-trending faults are also noted locally and played a critical role in development of the Zone 2 basement-hosted mineralization.

Jan 1, 2020

By V. G. Papangelakis, J. E. Dutrizac, G. Azimi

A new model capable of predicting the solubility of calcium sulphate solid phases in zinc sulphate processing solutions from 25 to 95°C was developed. The model uses the Mixed Solvent Electrolyte (MSE) model of the OLI systems software to calculate the mean activity coefficients of the electrolyte species. The model was tested using recently developed experimental measurements. It was shown to predict accurately the solubility behaviour of calcium sulphate in multi-component zinc processing solutions containing ZnSO4, H2SO4, MgSO4, MnSO4, Fe2(SO4)3, Na2SO4 and (NH4)2SO4. The model can also explain the complex effect of coexisting metal sulphates on the solubility of the CaSO4 phases. The model is a practical tool for assessing the process chemistry of a wide variety of complex aqueous processing streams.

Jan 1, 2008

By Ernest A. Hodgson

A SERIOUS hazard which must be faced in some mines, though quite absent in others, is that of rockbursts. Bursts cannot be wholly avoided in such mines, but the hazard would largely disappear if they could be predicted. The problem of prediction resolves itself into that of measuring pressure in the mine and determining when that pressure nears a critical value. The geophysical approach to the problem lies in discovering some physical property of the rock, which varies with pressure, which can be measured for rock in place, and for which the indication of critical conditions is sufficiently definite and open scale. A physical property, suggested first in connection with earthquake pre-diction, is that of sub-audible snapping. It was argued that, as the pressure grows, the rock probably yields microscopically and that minute snapping occurs which is so faint as to be inaudible to the unaided ear. Experience has proved this to be the case. Following other earlier work begun early in 1939, experiments with this method were initiated at Lake Shore Mines in 1941, and equipment was slowly being developed in practice when, fortunately, it was found possible to by-pass this tedious development programme. Experiments with sub-audible snapping in mine rocks had been carried out by Dr. L. A. Obert of the U.S. Bureau of Mines and his associates over a period of about four years. An amplifier and a recorder were developed, each reasonably satisfactory in practice. Lake Shore Mines offers a tempting field for rockburst research. Dr. Obert was invited to test his equipment in this and other mines in Ontario and did so. As a result, he and the administrative personnel of the Bureau became interested in the Lake Shore experiments co the extent of most generously arranging for the manufacture of sets of their own designed equipment for use in this programme. The first three sets of recorders were ordered at once and were delivered in May, 1942. A second group of three sets, incorporating various improvements indicated by experience both in the United States and in Canada, reached Kirkland Lake in April, 1943. The pick-up devices, known as geophones, were made in the electronics laboratory at Lake Shore by Mr. Zack Gibbs, who has had charge of all the instrument development in this re-search.

Jan 1, 1943

By F. Vagnon, A. M. Ferrero, M. Pirulli, A. Segalini

"The topic of this study is the design of flexible fences to mitigate the risk due to debris flow phenomena by means of theoretical and experimental studies analysed in framework of the Rock Engineering System (RES).The study of the interaction between debris flows and flexible barriers is a major challenge since many different aspects concerning both the slope characteristics and the structure features are involved. Debris flows are often triggered by the mobilization of debris deposits that are generated by rock fall of adjacent rock walls. The rock debris deposits are difficult to be characterized by the physical and mechanical point of view due to their large variability in volume distribution and, moreover, when dealing with high mountains environment, they are also strongly affected by the presence of water at different phases (solid or liquid) depending on the temperature. The debris deposit turns unstable in relation with the geotechnical and environmental features of the areas and the instability evolution in high mountain steep valley is often a debris flow. Debris flow destructive potential is very high and protections are often needed to reduce the debris flow risk.This complexity determines the needs of comprehensive study able to include the global basin dynamic and the environmental conditions. An a-priori analysis of the influence of the different aspects can be useful to focus on the real driving aspects of the problem. Due to the complexity of the system the application of the RES methodology is recommended in order to clearly define the different assumptions needed, their influence on the simulations and a comparison among them.RES allows investigating triggering criteria, flow and depositional processes and interaction of flows with protection fences in a rational way. For this purpose, an interaction matrix is created: it summarizes the key geotechnical parameters that influence debris flows, their interactions and debris/engineering protection opera behaviour. The goal is to quantify the diagonal-off terms to assess the residual risk after barrier construction, using back analysis from real debris flow event and data collection from literature.This methodology is applied to analyze a debris flow event in the Italian Western Alps where numerical analyses are carried on to assess flow characteristics to be used for fence design through the application of an analytical and numerical model developed by the authors (Brighenti et al, 2013). In particular, the velocity and deposition heights have been estimated using the numerical code RASH3D (Pirulli, 2010), which is a single-phase model based on depth-averaged Saint Venant equations. Pathways of different lengths are studied to assess the input data necessary to design the protection barrier and to determine the associated risk. Simulation of the barrier at different places along the valley will also allow to determine optimal barrier location in terms of minimum residual risks by comparing the velocity, the volume and the energy of the debris after the barrier impact.The work will produce a possible design scheme to be adopted in this environment."

Jan 1, 2015

By Erik Q. Dahl

The strength of green and sintered pellets during reduction under various conditions in a laboratory kiln has been investigated. Equipment and test methods are described, together with the results obtained. The strength of sintered pellets drops sharply when the reduction starts, and goes through a minimum at the 70 per cent oxidation level. At more advanced reduction, the strength increases with increasing metallization. Successful use of green pellets as kiln feed requires that more attention be paid to the pellet preparation than is necessary when producing pellets for separate sintering. In particular, the ores have to be ground to a greater fineness. The initial strength of green pellets is low. Below the 70 per cent oxidation level, however, the strength of these pellets is about the same as the strength of sintered ones. Additions of such materials as silica, limestone and anthracite coal; within reasonable limits, affect the strength only slightly.

Jan 1, 1966

By Jamal Asfahani

Abstract - Natural gamma ray well logging, an effective tool in geophysical prospecting, is used to investigate the radioactive and phosphatic layers in the Khneifiss mine in Syria. The interpretation of the gamma ray measurements, using numerical methods of analysis developed previously and applied successfully in some phosphatic areas in Syria, make it possible to define precisely the phosphate thickness from place to place in the study area. This technique has been successfully applied while studying seven boreholes in the area. Sixty-three core samples from phosphatic layers in the boreholes have been analyzed, using gamma ray spectrometry for the determination of P2O5 , U, Th, and K. Good correlation between P2O5 content and U concentration has been found. The total count gamma logs correlate reasonably well with the U core analysis, suggesting that radioactive equilibrium exists in the U decay series. These gamma logs can be therefore used effectively to quantitatively map the distribution of P2O5 and U. The characteristics of both subsurface phosphatic sand and phosphatic rocks have been investigated and outlined using a statistical approach. The affinity of uranium to some trace elements such as V, Sr, Cu, and Ni has been verified using correlation matrices of these elements.

Jan 1, 2002

By M D. Winning

The historical development of the elemental sulphur recovery industry in Western Canada is reviewed for the period 1952 to 1965. A brief technical description of a typical modified Claus sulphur recovery unit is presented. Some predictions are made concerning the future of the elemental sulphur recovery industry in Western Canada. THERE are evidences of sulphur or its compounds having been used for religious and medicinal purposes as far back as we have a recorded knowledge of history. As typical examples, sulphur was burned as a sort of inverse incense to drive away evil spirits at religious festivals, sulphur ointments were used by the early Egyptians to cure eye ailments, and hot sulphur-spring water was used as a cure for a variety of ailments. Thermopyle was called "Hot Gates" be-cause of its fame as a spa as well as a mountain pass. The Romans discovered the sulphur deposits in Sicily and mixed sulphur with bitumen for incendiaries; and, of course, anyone familiar with the travels of Marco Polo knows about the Chinese development of gunpowder, which contains sulphur. In some aspects things haven't changed much today. We still use sulphur-bearing ointments, and we still use the hot sulphur springs such as the one at Banff in Western

Jan 1, 1965

By B. G. Cousins, L. Racine, R. S. MacPhail

"FLEX 31 is a chemically enhanced sodium isopropyl xanthate that has shown improved collection properties over SIPX for copper-bearing and copper-activated minerals. Characteristics such as improvement of recoveries with lower dosages and high pyrite and pyrrhotite rejection capabilities have all been exhibited by FLEX 31.The most improved results have been seen insphalerite flotation. Plant trial work carried out in the zinc circuit at the Louvicourt Concentratorin northern Quebec has produced data showing superior grade and recoveries from rougher concentrates that previously had not been attain-able with other reagents effectively. The improvement over SIPX adds up to an almost$1,000,000 annual improvement on the mine’s bottom line at present zinc prices.IntroductionSodium Isopropyl Xanthate (SIPX) is one of the most popular flotation chemicals on the market today. Somewhat more specific than amyl xanthates, SIPX is used in a variety of ores like copper/zinc, lead/zinc, arsenopyrite/pyrite, and many others (Melis et al., 1991). An investigation carried out by Tennants Research Technology Applications (TRTA), a division of Charles Tennant & Co. (Canada) Ltd., produced a chemically enhanced SIPX that has shown all the advantages of normal SIPX along with improved recoveries of copper and copper activated minerals. The new product has been named FLEX 31. Currently, FLEX 31 is manufactured at the Prospec Chemicals, another division of Charles Tennant & Co. (Canada) Ltd.A large amount of laboratory testing pro-grams have been carried out with FLEX 31 todate (MacPhail and Cousins, 1995; Cousins and MacPhail, 1996). One of the minerals that has a defnite affinity to improved fotation is sphalerite (ZnS). Once activated with copper sulphate, sphalerite has produced some of the most spectacular test work when FLEX 31 is compared directly to SIPX. Plant trials of FLEX31 at Aur Louvicourt Inc. carried out in 1995show that FLEX 31 is far superior to SIPX for activated sphalerite flotation."

Jan 1, 1997

By Andrew Gillam

Outline of Presentation ? AMEC overview ? Benchmarked companies ? GRI 3.1 Guidelines ? Best practice examples ? Report content and boundary ? Strategy and profile ? Environmental ? Social GRI G3.1 ? Gold Standard for Reporting ? GRI ? Global Reporting Initiative ? 1997 outgrowth of Coalition for Environmentally Responsible Economies (CERES) and UN Development Program (UNDP) ? Official collaborating centre of UNDP and works in collaboration with UN Global Compact ? Coalition of companies, business organizations, accounting firms, CSR consulting firms and nogovernmental organizations (NGOs) ? Mission: develop and disseminate globally applicable Sustainability Reporting Guidelines ? Now de facto CSR reporting standard; appeal lies, in part, with supported flexibility in reporting approach and scope ? Latest generation G3.1 (March 2011); includes expanded guidance for reporting on human rights, local community impacts and gender

Aug 1, 2013

By K. Meshinchi Asl

In this study the effects of T4 and T6 heat treatments on microstructural characteristics of AZ91 alloy containing Rare Earth elements have been investigated. Formation of intermetallic Al1 1RE3 needle shape particles which have a good thermal stability reduces both formation of ß(Mg17A112) and discontinues precipitation in AZ91 alloy which are dominated at the grain boundaries and are responsible for poor mechanical properties specially in elevated temperatures. For AZ91-RE samples both T4 and T6 heat treatments led to a continuous precipitation of ß particles at the grain boundaries after aging. However, in AZ91 samples (with no Rare Earths) precipitation was discontinuous at grain boundary areas. This type of precipitation is one of the main reasons of poor mechanical properties of this alloy at elevated temperatures.

Jan 1, 2007

By E. G. Langille

"The Premier mine; owned by Silbak Premier Mines; Limited; is 14 miles from Stewart at the head of Portland canal. Development of the property began in 1918; and since chat time a very large amount of gold and silver as well as some lead and copper have been produced from the mine.The area in the vicinity of the mine is underlain by greenstones tuffs, and sediments of Mesozoic age, belonging to the Bear River formation of the Hazelton group. These rocks are intruded by a stock 2 miles in diameter, composed of orthoclase porphyry and called the Premier porphyry. It sends numerous sill-like and dyke-like tongues into the Bear River formation, and is intruded in turn by a granodiorite outlier of the Coast Range batholith. The orebodies occupy fractures and fracture or shear zones. Primary ore consists chiefly of pyrite, galena, and sphalerite, with some chalcopyrite. The upper 300 feet, or locally 600 feet, contained presumably secondary silver minerals."

Jan 1, 1954