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By Kent Zehr

Suncor Energy Inc. is an integrated producer and refiner of oil and gas headquartered in Calgary, Alberta. The bulk of revenue comes from the Oil Sands Group (OSG) operating in the McMurray formation of the Athabasca Oil Sands. Located some 25 kilometers north of Fort McMurray, Suncor OSG began life in 1967 as Great Canadian Oil Sands, the first operator to successfully enter commercial production of synthetic crude oils from the area. For most of the last decade, dramatic growth has been the standard mode of operation for Suncor OSG. Production of synthetic crude first reached 100,000 barrels per day in 1997 and less than five years later is averaging in excess of 200,000 barrels per day. Within this dynamic organization, Suncor Extraction is the business unit that processes run-of-mine ore into clean diluted bitumen for Upgrader feedstock. Extraction also delivers and places the barren sand and process affected water into tailings storage in one of several ponds from which water is recycled to support the various processes. For reference purposes, Extraction on a typical day currently receives more than 400,000 metric tons of oilsand ore, which is all processed to water based slurry for separation in one of two extraction plants. Separated tailings are disposed of as a slurry and the cleaned bitumen froth is diluted with naphtha and sent to tankage for storage until required by the Upgrading Unit. As a consequence, on a typical day Suncor Extraction pumps more than 1,000,000 tonnes of aggressive slurry into and out of the two extraction plants.

May 1, 2003

By Zohreh Kazemi Motlagh, Virginia T. McLemore

Critical minerals are nonfuel minerals, essential to the U.S. economy and national security, whose supply chain may be disrupted. Mine wastes are potential sources of critical minerals. The goal of this project is to estimate and characterize critical minerals endowment in three mining districts in New Mexico: Black Hawk (Grant County), Hillsboro (Sierra County), and Magdalena (Socorro County), and assess their acid-generating potential. The Black Hawk district is an arsenide five-element vein deposit (Ag, Ni, Co, As, U, Bi, and local minerals like Pb, Cu, Zn, W, and Sn). The Copper Flat mine in Hillsboro district is a copper porphyry deposit. The Kelly mine in Magdalena was first mined at 1878 and are carbonate-hosted Pb-Zn deposits. Mine waste rock piles and tailings are sampled using USGS Beta sampling procedure. Geochemistry results show that Black Hawk district mine wastes samples are elevated in Ag (>200 ppm), Co (290 ppm), Ni (2,130 ppm), and Zn (8,463 ppm). Copper Flat mine tailing is elevated in Bi (111 ppm), Cu (7,453 ppm), and Zn (2,360 ppm). Downhole profile plots in Copper Flat show the positive correlation between Cu, S and Te values. Magdalena samples are elevated in Cu (5,700 ppm), Zn (129,500 ppm), and Pb (58,100 ppm). Determination of acid-generating potential in these areas suggests that Black Hawk district mine wastes are non-acid-forming while high S present in some Copper Flat and Magdalena samples can potentially cause acid mine drainage.

Feb 1, 2025

By Jacques Ouellet, Ferri Hassani

"Within the mining industry paste backfill technology has evolved over the last two decades. This technology aims at producing safe and cost effective backfill of high strength. When used as cemented backfill underground the usual practice in the mining operations was to consider the backfill as a component under the production engineer responsibility. With its growing use in various site conditions some problems were encountered. Over time the mechanical characteristics of paste backfill could deteriorate. Investigations on these problems brought an increased understanding of paste backfill chemistry. Effectively, paste backfill is produced with tailings slurry having sometimes very complex chemistry and mineralogy. The bonding agents can be sensitive to the chemistry of these slurries. Today, a new understanding of the complex chemical reactions involved in cementing paste backfill is derived from concrete research literature. Cemented paste backfill is a manufactured product and as thus all steps involved in its making must be looked at. Both the processing engineers and mining engineers need to be involved. The proposed paper will go over the various developments and new understanding gained over the years on paste backfill chemistry. The authors had the opportunity to work with various Canadian mines that implemented paste backfill in their operations. Chemical alterations case study will serve to illustrate the importance of a good understanding of cement and paste chemistry. The authors will then conclude on research orientations needed to bring a more efficient use of paste backfill technology. The crucial role of the processing engineers in the paste backfill manufacturing will be discussed.INTRODUCTIONPaste backfill is usually prepared from a mixture of solids and water containing at least 15% particles smaller than 20 microns with the addition of binders for mechanical strength. Historically, tailings had been classified to extract the fines and only the coarse part was placed underground as sand slurry. Paste fill was researched in the last three decades to enable mining operations to use all the tailings, including fines, in backfill. The outcome of the early studies showed that paste fill provides high strength but due to preparation complexities and transportation problems is expensive. A greater understanding of the transportation mechanisms and advances in dewatering technology in recent years has resulted in more practical use of paste backfill."

Jan 1, 2002

By Emmanuel Pornillos

Dado que en el Perú, la actividad minera utiliza el minado subterráneo para la explotación de minerales, se revalúa el uso de estos en pasta cementada para el relleno de las labores subterráneas, así como los relaves desaguados para su disposición superficial. En ese sentido, el presente texto señala las experiencias de diseño y operacionales de sistemas múltiples para la aplicación de relaves en superficie y subterráneo en el Perú, de forma que se pueda optimizar la selección de equipamiento y una operación robusta.

Sep 1, 2013

By W. B. Timm

Introduction In preparing this paper on Recent Developments in Gold Milling Practice, the idea occurred to me that possibly the best way to deal with the subject would be to take you in thought on a visit to the principal gold mining camps of the Dominion, starting at the east and finishing up in the west, and noting, as we go, the outstanding improvements that have been made in the last few years in the practice of gold milling. Before beginning this tour, I desire to emphasize the debt this country, and particularly our mining industry, owes to that body of trained and experienced men, little heard of, but who, working quietly on their problems, are responsible for these improvements. The metallurgists, to whom I refer, have solved many difficult problems for the mining industry, in connection with the treatment of our complex ores; for instance, the silver-cobalt ores of the Cobalt district, the gold ores of the Porcupine district, the gold-telluride ores of the Kirkland Lake? district, the copper-gold ores of Noranda, the arsenical-gold ores of the Beattie mine, the copper-zinc ores of Flin Flon, and the lead-zinc ores of Kimberley. In doing so, they have maintained the high technical standards of the profession, and the practices thus evolved are noteworthy for their high degree of efficiency. When the price of gold increased from $20.67 to $35.00 an ounce, what had formerly been thought to be a low tailing became almost an ore, so that the metallurgists are now busily engaged upon the problem of putting this railing back in its proper place of being a tailing once more, or from its value, at the present price, of anywhere from 50 cents to a dollar or so per ton, to a few cents per ton. Owing to the changing prices of the metals in the world's markets, still greater improvements in metallurgical practices are imperative. An important contributory factor towards improvement in ore dressing is the aid furnished by the microscope in the examination of ores and mill products. By making possible the determination of the mineral constituents of the ore, their association, and grain size, it gives the investigator a knowledge of his problem, before he does any actual test work. In the Mines Branch laboratories at Ottawa, its use has enabled us to predict how an ore should respond to various methods of treatment.

Jan 1, 1935

By C. W. Davis

During the second year of its existence, the Ore-Testing Section has actively prosecuted work in the standardization of testing methods, in conducting routine tests and analyses for other Government agencies, and in the determination of recommended processes for the treatment of representative ores from mining districts. Close cooperation has been maintained between the members and units of this Section and those of other Sections, J. A. Woolf and J. B. Clemmer have continued to act in an advisory capacity and R. E. Head has contributed valuable assistance in the microscopic examination of ores and metallurgical products that did not respond readily to standard treatment methods.

Jan 1, 1938

By C. W. Davis

During the second year of its existence the Ore-Testing Section has actively prosecuted work in the standardization of testing methods, in conducting routine tests and analyses for other Government agencies, and in the determination of recommended processes for the treatment of representative ores from mining districts. Close cooperation has been maintained between the members and units of this Section and those of other Sections. J. A. Woolf and J, B. Clemmer have continued to act in an advisory capacity and. R. E. Head has contributed valuable assistance in the microscopic examination of ores and metallurgical products that did not respond readily to standard treatment methods.

Jan 1, 1938

By E. Fried

Cemented paste backfill (CPB) is an innovative tailings management method that consists in returning considerable amounts of mine tailings into the underground mine openings. The filled stopes thus participate to the ground support that allows maximizing orebody extraction and a safer environment for the mine workers. There are also significant environmental advantages of using CPB. Indeed, up to 50% of the concentrator tailings can be backfilled, leading to a smaller volume of problematic waste materials to be managed at the surface. Once the CPB is placed, or when the mine is flooded at its end-life, the backfill is subjected to underground water flows that may leach and spread the pollutants (mainly metals, sulphates, and acidity) which can contaminate the underground waters. The aim of this study is to characterize the leaching properties of CPB material and to identify the cement phases that ensure the metal fixation. A laboratory procedure was implemented consisting in the preparation of various paste backfill mixtures using sulphide-rich and sulphide-free materials, different types of binder, and mixing waters having various sulphates, copper and zinc concentrations. After 90-days curing time, the samples were submitted to column leaching tests. The CPB materials were flushed each day with 100 ml of deionised water during 100 days. The collected leachates were then analyzed for pH, Eh, electric conductivity and chemical composition. For some samples, a differential acid neutralisation test was carried out. The objective of this experiment is to dissolve selectively the hydrated phases by adding incremental acid concentrations. By analyzing punctually the equilibrated solutions, the composition of the dissolved phases and their metal content can be estimated. The leaching test results showed that the pH of the leachates remains alkaline during the test period. When the pH decreases under 10 (after 30 days), different behaviours in terms of chemical element release (especially for zinc) were observed. During the test, the oxidation of pyrite seems to slow down, probably due to passivating phenomena. Moreover, the differential acid neutralisation test results allowed a better understanding of the CPB mineralogy and the Zn-bearing cement phases. Zinc and the other metals seem to be fixed within a calcium-magnesium silicate.

May 1, 2007

By William Cochran

The mineral waste disposal system at the Grace Mine, Morgantown, Pa., was designed to minimize environmental effects while allowing much of the waste from the iron mine, mill, and concentrator to be utilized. Standard cost estimating procedures were used by the Bureau of Mines to determine waste disposal costs. Mill tailings and rock waste disposal costs were estimated at $0.151 and $0.276 per ton, respectively, for the 1965-67 production period. Total waste disposal cost was reduced about $0.015 per ton by utilizing part of the waste as aggregate. The net average cost for disposal of all mineral waste was $0.189 per ton.

Jan 1, 1969

By Hao Zhang, Dezhou Wei, Qiang Zhao, Caie Zhang, Baoyu Cui, Xuetao Wang

"Nowadays, long periods of relatively low iron ore prices have made the steel industry get the greater pressure. To develop appropriate processing technology based on characteristics of the iron ore, so as to reduce the beneficiation costs, is crucial to the improvement of iron and steel enterprise competition. For a typical low-grade iron ore from northeast China, beneficiation process research was conducted based on the in-depth studies of ore characteristics. Results show that the iron grade of the ore was 31.56%, the content of FeO was 6.59%, the main iron minerals were hematite and magnetite with fine dissemination sizes and partly scattering in gangue; With the grinding fineness of 65% passing 0.074mm, and regrinding fineness of 90% passing 0.074mm, the concentrate with 66.80% iron and recovery of 82.90% was obtained via the combined flowsheet of stage grinding – classification – gravity concentration – low and high intensity magnetic separation – reverse flotation. Ratios of gravity concentration and low intensity magnetic separation were 70.21% and 7.57% respectively in 40.42% of total concentrate yield; The loss of micro-size fractions can be reduced by feeding spiral tailings into magnetic separation and flotation; It’s helpful in reducing the dosage of reagents and beneficiation costs by increasing the throughput of gravity concentration and outputting concentrate of low intensity magnetic separation.INTRODUCTION Iron and steel industries are facing the increasing pressures in the continued falling iron ore prices. In order to improve the competitiveness, it is extremely urgent for them to develop more appropriate separation process for the reduction in iron ore beneficiation cost. As a typical low-grade iron ore, Anshan-type iron ore is one of the most important iron ore resources in China [1-3]. The flowsheet of stage grinding and separation contained the classification of the coarse particles and the fine particles, the gravity concentration, the magnetic separation and the anionic reverse flotation has been widely applied for Anshan-type iron ore. With the appropriate separation progress as well as equipment, satisfactory separation results had been obtained, and mineral particles with different size were recovered separately [4-7]. However, the low recovery of fine mineral particles and the relatively high beneficiation costs still prevented the efficient application of the process [8]. For a Anshan-type low-grade iron ore, a typical process flowsheet, as mentioned earlier, with stage grading, classification of the coarse particles and the fine particles, gravity concentration, magnetic separation, anionic reverse flotation was adopted currently. And the concentrate with 67.10% iron and recovery of 75.50% was obtained and the gravity concentrate accounted for 39% of the total concentrate. However, a large amount of fine liberated iron ore particles were lost in the tailings."

Jan 1, 2018

By I. G. L. Sinclair

The Selbaie deposit is located in northern Quebec. It is comprised of three distinct, but genetically related, Cu-Zn-Ag ore bodies which also contain economically significant amounts of Au. The deposits are Archean in age and volcanogenic in origin. At Selbaie, ore microscopy has been employed to aid in planning of ore beneficiation methods and to monitor the ongoing performance of the concentrator. Examples of both types of study are described. Early in the life of the mine, excessive amounts of Zn appearing were found to be appearing in the Cu concentrate. Microscopic examination of concentrates showed that this was being caused by the presence of coatings of supergene chalcocite on sphalerite grains. Fine coatings of supergene galena and chalcopyrite were also observed on some sphalerite grains. The presence of Ag and Au in the ores makes an important contribution to the revenue of the mine. The various modes of occurrence and mineralogical relationship of these two metals are described and discussed. Monitoring of the ongoing concentrating process at selbaie is done by qua-litative and quantitative examination of products collected at various points along the circuit. Causes of such problems as excessive loss of metals to the tailings or inefficient recovery of individual metals, can often be identified and possible solutions proposed.

Jan 1, 1989

By Laros T, Schoenbrunn F

Deep paste thickeners have been proven capable of consistently producing medium to low slump material for disposal without the need for filters. However, proper design of the entire system is critical for a paste project to he successful. Some of the factors that must be carefully considered in design of a paste system include thickener sizing, tailings inipoundineni design, underflow pumping, and control system.

Jan 1, 1998

By N Haque

Base metal ores contain low levels of toxic/hazardous elements such as arsenic, antimony, bismuth, cadmium, lead and mercury. Given the large tonnage of base metal ores mined and processed each year globally, the accumulated mass of minor elements introduced into the biosphere is large and could be expected to have a significant environmental impact. Life cycle analysis (LCA) is a methodology that has been developed to assess the environmental impacts of material supply chains over their entire life cycle. Assessing the toxicity impacts of metallic wastes and incorporating these impacts into LCA methodology is not a simple task given the complexity of the issue. However, research and methodology development is in progress internationally to address this. Despite limitations concerning the lack of a coherent framework for characterising the toxicity impacts of metals, including issues such as bioavailability, a study was carried out to give first estimates of the relative toxicity impacts of various waste streams from metal production processes. The wastes considered were: red mud; sulfide tailings (copper, nickel, lead/zinc); lead/zinc slags; synthetic rutile residue; iron oxide residue; and copper slags and anode slimes. These toxicity estimates can be considered the æworst caseÆ scenario for these wastes, where all the metals present are bioavailable. Combining estimates of the amounts of the various waste streams produced in Australia each year with the toxicity results showed that despite their relatively low human toxicity impact per unit mass compared to some other waste streams, red mud and the various sulphide tailings had the highest annual human toxicity load on the environment, along with copper smelting slag and dust. Data from the pH dependent leaching test reported in the literature were assumed to represent first approximations of metal bioavailability and used to compare the two approaches to estimating the toxicity impacts of red mud.

Jan 1, 2009

By W. W. McClintock

A column flotation system was designed to conduct release analyses of a very finely disseminated, stratiform, copper ore from the Denali Copper Prospect, Alaska. Chalcopyrite is finely disseminated in a carbonate matrix and pyrite is disseminated in both the chalcopyrite and gangue, requiring grinding to 20 microns for adequate liberation. A 25 mm x 2.4 m glass flotation column was designed. The ore and its flotation tailings were repeatedly floated to obtain a rougher concentrate, which was repeatedly floated to produce release fractions. These were analyzed for copper, iron calcium and magnesium. Release curves were plotted. The procedure was replicated at each of two grinds; 99% and 88% passing 37 microns (400 mesh), and should find application for flotation characterization and process selection. Bond grindability work was also conducted.

Jan 1, 1994

By C. W. Davis

This report follows the same general scheme as did its predecessors; it begins with a dissertation on some phase of ore-testing, continues with results of investigations of ore-treatment methods and of metallurgically important analytical processes, and concludes with an exposition of tests made by established methods on typical ores selected as representative of certain mining districts. One of the first things that is done after an ore has been received is to look at it under the microscope. Microscopic examination serves as an important complement to chemical analysis in interpreting the percentage composition in terms of minerals. If it has been found difficult to treat an ore, the reasons for this action and indicated methods to overcome the difficulties may be ascertained by testing with a microscope. For example, failures in selective flotation have been traced to intimate mineral association and changes in mineral surfaces through incipient oxidation. The importance of surface stains or tarnishes and the presence of adhering slime particles have been found to be responsible for the difficulty experienced in the treatment of certain gold ores.

Jan 1, 1938

By C. W. Davis

This report follows the same general scheme as did its predecessors; it begins with a dissertation on some phase of ore-testing, continues with results of investigations of ore-treatment methods and of metallurgically important analytical processes, and concludes with an exposition of tests made by established methods on typical ores selected as representative of certain mining districts. One of the first things that is done after an ore has been received is to look at it under the microscope. Microscopic examination serves as an important complement to chemical analysis in interpreting the percentage composition in terms of minerals. If it has been found difficult to treat an ore, the reasons for this action and indicated methods to overcome the difficulties may be ascertainedd by testing with a microscope. For example, failures in selective flotation have been traced to intimate mineral association and changes in mineral surfaces through incipient oxidation. The importance of surface stains or tarnishes and the presence of adhering slime particles have been found to be responsible for the difficulty experienced in the treatment of certain gold ores.

Jan 1, 1938

By P. L. Dunn

Automatic control of fine coal cleaning circuits has traditionally been limited by a lack of sensors. Although several nuclear-based analyzers are available, none have seen widespread acceptance. In this investigation, image analysis is used for on-line determination of ash content in fine coal slurries. The ash content of a flotation tailings stream is correlated to the mean gray level of the slurry. Based on a 90% prediction interval, an analysis of sensor performance indicates an accuracy of 73 ± 4% ash over a range from 65-90% ash. While this result is comparable to existing nuclear-based analyzers, the video-based system is only a fraction of the cost. The sensor is currently installed at the Middle Fork preparation plant owned by Pittston Coal Company.

Jan 1, 1997

By Aixiang Wu, Minjie Zhang, Zhuen Ruan, Yiming Wang

 The paper combines theoretical and experimental analysis to improve the accuracy of predicting paste yield stress by slump flow. It derives an analytical model of slump flow for yield stress, providing a theoretical basis for quantifying the rheological properties of paste with slump flow. The study uses three different tailings-prepared pastes and constructs an empirical yield stress model, showing high accuracy and good generality.

Aug 1, 2023

By J. A. Holmes

Due to varying and complex mineralogy, the flotation tailings from the Chingola Concentrator have, for some years, contained upwards of 0.4% acid soluble copper. In 1968, an investigation was initiated, to determine a method for recovering this acid soluble copper. This initial investigation concluded with a recommendation to install a leach-solvent extraction-electrowinning plant at Chingola, to treat up to 900 000 tonnes of material per month, for an additional copper production of some 4 500 tonnes per month. The process consists basically of six stages :- Materials reclamation handling and preparation, acid leaching in air agitated pachucas, solid-liquid separation by countercurrent washing in thickeners, solution concentration and purification by solvent extraction, copper recovery by electrowinning, and residue neutralisation and disposal. This paper describes the development of the main parameters for design of each of the six sections, and gives details of the final plant design. Problems encountered in commissioning and initial operations are commented on, particularly insofar as they indicated any errors or misjudgements in the design. The choice of materials of construction is commented on in some detail.

Jan 1, 1976

By R. T. Erskine

"The No. 6 orebody is located 6 miles from the main op.eration of Brunswick Mining and Smelting Corporation Limited and includes open-pit and primary gyratory crushing facilities. Ore is transferred by truck to the secondary crushing facility at the main plant. About 3,500 tons of ore per day are crushed to minus % in. and ground to 68 per cent minus 400 mesh in rod and ball mills for flotation feed. Conditioning and aeration precede rougher flotation, and four stages of cleaning bring concentrates to a grade of 42 per cent Pb + Zn + Cu. Middling products are reground and refloated in a secondary flotation circuit, producing a cleaner feed and a final tails product. Primary bulk concentrate is treated with sulphur dioxide and steam-heated to l 70°F and the majority of the gangue is floated off, leaving a product that assays 57 per cent combined Pb + Zn + Cu and is suitable for marketing. This material is thickened, filtered, dried and loaded into railway cars for shipment to the smelter. Reagent use on flotation is conventional, with many compromises in dosage required to maintain the recovery of lead and zinc in the most advantageous proportions. Many refinements in the flowsheet have been made since start-up in 1966, and more may be made as laboratory and plant testwork indicate possible improvements."

Jan 1, 1971