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By J. G. Peacey, G. Csicsovszki

The target of this study was to clarify the role of lead on the dissolution of gold in the (NH4)2S2O3-Cu leaching system via chronopotentiometry, linear sweep voltammetry and chronoamperometry. It was found that the dissolution of gold was significantly increased with lead concentration up to 10 mg/1 Pb in the system of 0.1 M (NH4)2S2O3 and 50 mg/1 Cu. \/oltammograms suggested that the anodic dissolution of gold was virtually independent of lead concentration in the range of 1-10 mg/1 in 0.1 M (NH4)2S2O3 solution while in solutions containing copper as well, addition of lead increased the anodic dissolution of gold.

Jan 1, 2011

By Jacek Paraszczak

As the deposits located closer to the surface are getting depleted, more and more Canadian mines produce ore from considerable depths. Deep mining represents a number of serious challenges including high rock temperature. Conventional diesel powered loadhaul- dump machines and trucks so widely used in metal mines constitute an additional source of heat and noxious gases. Due to this, they have a substantial adverse impact on a quantity of fresh air required and a cost of ventilation, particularly since the mines have to meet more and more stringent regulations in this respect. In this context, the paper examines possible alternatives for diesel powered equipment, both these commercially available as those at the stages of prototypes or under development. They are reviewed with regards to their principles, required infrastructure, stage of technology development and its progress. The questions of their flexibility, practicality and economic viability are also addressed. Following the above a potential for their implementation and possible benefits (if any) in the conditions of deep Canadian mines is discussed. The paper concludes with short to medium term predictions concerning the most promising drive alternatives for vehicles destined to operate in deep metal mines.

Feb 1, 2008

By J. L. Jambor, M. J. Baker, M. J. Logsdon

"Abstract - Prior to the development of the Diavik Diamonds Project, baseline studies were conducted to determine the geochemical characteristics of four kimberlite orebodies as an aid in the design of both the water-management system and the facilities for containment of processed kimberlite and ore stockpiles. Materials tested included field samples of volcaniclastic and pyroclastic kimberlite, processed kimberlite (i.e., kimberlite ore which had been screened and washed as part of the processing procedure), and sedimentary mudstone (a minor xenolithic unit which was assimilated during kimberlite emplacement). Approximately 200 samples of kimberlite materials were collected as part of the geochemistry program. Test-work included whole-rock chemical analyses, acidbase accounting, kinetic leach tests using columns, and mineralogical analyses. Diavik kimberlite has major oxide and trace-element concentrations consistent with global averages for kimberlite. The mean total-sulfur content of the kimberlite material is 0.22 wt% S, but with a significant range. The kimberlite has an excess of carbonate minerals over sulfide minerals (average CO2 = 4 wt%, present mainly as calcite), and has a mean neutralization potential of 311 kg CaCO3 equivalent/tonne. A reactive form of framboidal pyrite associated specifically with the mudstone xenoliths is the primary source of sulfide-sulfur. Long-term kinetic tests confirmed the preliminary interpretations that were made from the static-test results. Kimberlite and processed kimberlite are net acid-consuming materials that produce alkaline drainages and have low but detectable leaching rates for SO4 and specific trace metals such as Al, Co, Cu, Ni, and Zn. If segregated from the kimberlite, mudstone xenoliths are acid-generating (pH = 3) and produce an effluent with elevated concentrations of SO4, Fe, Al, Cu, Ni, and Zn. The study demonstrates that xenolithic units in Diavik kimberlites have an important effect on the environmental geochemistry of the ore rock. The mineralogy and aqueous geochemistry of the kimberlite materials are such that they may not be suitable for general earthworks or as an alkaline agent and should report to an engineered facility to protect site water quality."

Jan 1, 2001

By D. Nower

"The supply of copper is expected to be at a large deficit in 2012. To recover from these deficits mining companies are required to maximize production and there is no better way to accomplish this than to optimize the use of their mobile mining equipment fleets. To optimize these fleets, each equipment type has to be monitored in its own unique way. Automation would not only improve production, but also minimize the safety risks and eliminate planning errors. The automated vibration monitoring of multiple systems on the shovel can determine the machine’s condition at all times. This reduces unplanned downtime and keeps critical shovels in production. This paper will discuss the details of how shovels can be successfully monitored, continuously. INTRODUCTIONP&H Mining, part of Joy Global, is the world’s largest manufacturer of above-ground mining equipment. Its electric rope shovels, such as Figure 1, with capacities up to 115 tons (104.3 metric tons), are used for high production loading in surface mines; its draglines, such as Figure 2, have bucket capacities to 160 cubic yards (122 cubic meters). P&H also produces blasthole drills, mobile mining crushers and other essential mining equipment. Headquartered in Milwaukee, WI, the company does business on every continent, except Antarctica. ECONOMIC FACTORSDue to the global demands for metals and power, mines are required to operate at full capacity. Mine operations cannot afford any critical assets to shutdown unexpectedly; depending on the ore type and quality, downtime for a single shovel can be as much as $300,000 per hour.Electric rope shovels are one of the most critical assets in open pit mining. They are very large, complex machines with DC or AC motors, multiple reduction gearboxes (some of them complex planetary) and multiple large rolling element bearings. This complexity, combined with the tough 24/7 service, results in too much unplanned shovel downtime, which can affect the entire downstream process."

Jan 1, 2012

By Edward R. T. Tiekink

Metal complexes continue to find therapeutic applications for the treatment of a wide variety of human ailments. Amongst these, gold(I) thiolates are used to treat rheutmatoid arthritis but, usually in combination with other treatment or as a last resort. New therapeutic uses of gold, both as gold(I) and gold(III), are being sought, including against cancer, the focus of the present contribution. It will be demonstrated that certain gold(I) complexes show exciting cytotoxicity profiles, rivalling those of cisplatin and standard chemotherapeutic agents. More importantly, anti-tumour activity is demonstrated in vivo, albeit in a mouse model. The presentation will give a brief overview of ?metals in medicine? with a focus on gold and will summarise some recent advances in the development of goldbased anti-tumour agents.

Oct 1, 2003

By Somchet Vongpaisal

This paper presents the R&D results on the development of a new knowledge-based system for predicting stope instability and associated unplanned dilution in deep underground mining operations. A new prototype was developed based on databases generated from 3D non-linear elasto-plastic finite element stress analysis, heuristic rules, and case histories. This prototype aims to assist mine operators to make decisions on strategic mine planning and feasibility in a quick and efficient manner thereby minimizing risk on ground failure and optimizing mining costs.

Jun 1, 2012

By Joseph J. Poveromo

The blast furnace today continues as the primary production method of hot metal in large-scale steel production. The blast furnace process has been the target of repeated attempts to replace it with various process options, including direct reduction and coke-free smelting reduction. While these new technologies are being adopted in appropriate niches, the blast furnace has responded to the challenge by being amenable to continuous improvement. I will review the role of the blast furnace, major developmental and improvement trends, and then list the current important issues in ironmaking. I will outline the challenges to be faced by the blast furnace to maintain its position as the primary hot metal production process. The material presented here is an update of earlier presentations made in Stockholm, Sweden, 1996, Duluth, 1998 and Chicago, 2000.

May 1, 2003

By M. Matsuda

The Hitachi refinery of Nikko Smelting & Refining Co. Ltd. began its electrolytic copper refining operations in 1911. In December 2002, the refinery changed its operation scheme by introducing the ISA permanent cathode technology for the first time in Japan. The change resulted in higher productivity, better cathode quality, and lower operational costs. The operation has been continuously improved to reach a 20% higher production capacity than the original one. For the electrolyte purification process, the Hitachi refinery has developed a new process for removing impurities. The process involves As, Sb and Bi adsorption from the electrolyte by means of chelating and ion exchange resin. The new resin process will achieve higher efficiency in removing impurity.

Jan 1, 2007

By Y. Thibault, L. Morin, R. Cameron, D. Gould

"There are an estimated 50 to 100 million dry metric tonnes of low-grade nickeliferous pyrrhotite tailings in the Sudbury area alone, with an average nickel grade ~0.8% (plus cobalt). Pyrrhotite is a highly reactive sulphide mineral that has the potential to generate acidity; consequently, it is stored in large tailings ponds that require perpetual treatment to avoid the production of acidic drainage. Re-processing this material using bioleaching technologies has the potential to recover valuable metals, while reducing the toxicity, reactivity, and acid generating potential of the remaining residues. CanmetMINING is currently developing a stirred-tank bioleaching process to recovery nickel and cobalt from pyrrhotite-rich tailings. Stirred-tank experiments have been conducted with one tailings sample over a range of pH and temperature conditions, resulting in 80 to 90% and 70 to 80% leaching of nickel and cobalt respectively in 10 days.INTRODUCTION Sulphide tailings may represent a significant financial liability for mining companies as these wastes may produce acidic drainage under some disposal conditions. As a result, the companies must post financial bonds large enough to ensure there are sufficient funds for perpetual management of these wastes. At the same time, there are billions of dollars in metals incorporated into these mining wastes waiting to become valorized. Many sulphide tailings are amendable to bacterial oxidation for metal extraction. Re-processing of tailings using bacterial leaching has the potential to recover valuable metals from waste; and reduce the toxicity, the reactivity, and the acid generating potential of the remaining residue. By reprocessing these wastes there is an opportunity to significantly reduce liabilities and financial assurance bonds, while recovering metal values. There are an estimated 50 to 100 million dry metric tonnes of low-grade nickeliferous pyrrhotite-rich tailings in the Sudbury area alone with an average nickel grade ~0.8% (Peek et al., 2011) plus cobalt and copper. Pyrrhotite is separated from pentlandite concentrates by magnetic separation and flotation. It is already finely ground and has often been segregated from other tailings material, making „mining? relatively inexpensive. This represents roughly (> $100/ton) in contained value, with negligible mining costs. This paper reports on the development of a stirred-tank bioleaching process for recovering nickel and cobalt from pyrrhoitite-rich tailings, which is currently underway at Canmet MINING."

Jan 1, 2017

By S. Glen

Cyanide management practices on modern gold plants are becoming more onerous, due to environmental pressures, particularly for signatories to the International Cyanide Management Code. Operations are therefore seeking to reduce levels of weak-acid dissociable (WAD) cyanide reporting to spigot discharge as well as to any eventual discharges from the tailings storage facility (TSF). Current gold industry standard processes primarily include the oxidation of cyanide by means of sodium meta-bisulfite (SMBS, or SO2) with air, Caro&apos;s acid (H2SO5) or hydrogen peroxide (H2O2). These processes require the transport and usage of expensive oxidizing reagents, along with the safety and environmental issues associated with these corrosive and toxic chemicals. Maelgwyn Mineral Services (MMS) has developed the MMS CN-DTM process, which utilizes the Aachen ReactorTM, a high-energy mass-transfer superoxygenation system, in conjunction with an activated carbon-based catalyst and no additional reagents, to increase the rate of cyanide oxidation to cyanate, the thermodynamically more stable form. Testwork conducted at the Maelgwyn Australia testwork facility in Perth Australia is described, at both pilot scale and continuous bench-scale, on a sample of tailings effluent obtained from an Australian gold plant. WAD cyanide is demonstrated to be lowered using the MMS CN-DTM process from an influent of 130 mg/L to the required levels for discharge to TSF (<50 mg/L). The continuous test results showed stable operation over three residence time turnovers. The pilot-scale results demonstrated the efficiency of the process at the reasonably large scales required for engineering cost estimation.

Jan 1, 2011

By M. Nakai, G. Itoh, R. Yamada, A. Kurumada

In order elucidate the mechanism for poorer fatigue properties of 7000 series aluminum alloys than those of 2000 series alloys, the effect of the test environment on the fatigue crack growth of the two series alloys was investigated, considering the relationship to hydrogen embrittlement. Two 7075-type and four 2024-type alloys were T6-tempered and T4-tempered respectively, and subjected to fatigue crack growth tests in moist and dry environments. When tested in moist air, fraction of intergranular crack path was higher in the 7075-type alloy with coarse equi-axed grains than in the 2024-type alloy with similar microstructure. This was in accord with the larger crack growth rate in the 7075-type alloy. Both the intergranular crack path fraction and the crack growth rate were decreased by changing the environment to the flow of nitrogen gas. Thus, the large fatigue crack growth rate of the 7075-type alloy is attributable to hydrogen embrittlement.

Jan 1, 2015

By I. Clauzier

"A new method of managing electricity to reduce costs andimprove profits is discussed. Before taking steps to better manage electricity, it is essential to understand the terms peak demand and energy and their effect on an electrical bill. Knowing how electricity is presently used in the plant is the important first step. This goes beyond knowing how much electricity is used at each time of day, the individual contribution of every plant process to the total plant load must be known. At this point, each process is ranked according to importance to production in order to identify possible savings opportunities. These improvements can then be implemented by simply improving operations or in some cases, through the use of an automatic control system. IntroductionIn today&apos;s competitive environment, controlling costs is becoming increasingly important. All costs associated with operation must be controlled in an effort to improve competitive position. Electricity is a cost component that can and should be managed.Although the term management can mean different things to different people, the intent is always the same: to make the best possible use of existing resources, whether labour, equipment or electricity.The simple approach to managing electricity presented in this paper consists of four steps.I. Understand Peak Demand and Energy. It is essential to understand the terms, peak demand and energy and their effect on your electrical bill.2. Know Your Present Electrical Use. The present use of electricity in the plant must be known. This goes beyond simply knowing how much is used at each time of day, to accurately knowing how each process is contributing to the total plant electrical load, and ultimately to the electrical bill.3. Identification of Savings Opportunities. With this information, energy savings opportunities for reducing the electrical bill and improving profits can be identified.4. Implementing Improvements. Having identified areas of potential savings, improvements can then be implemented in order of their significance. This could be a matter of simply improving operations, or in some eases may mean the use of an automatic control system.These four steps can result in significant dollar savings."

Jan 1, 1987

It?s a pleasure to be with you in Vancouver today to reinforce the good work you and your companies do to develop and operationalize new technology as a lever to improve operational performance and reduce our impact on the environment in absolute terms. Although I will use the work we do at Shell to reinforce this perspective, the principles apply to all of us in this industry regardless of whether you are a producer or supplier. I?d like to help demystify the future of Canada?s oil sands based on Shell?s view of global energy developments, including forecasted demand. One of the incontrovertible truths of this era of global energy defines change as an unchangeable law of progress. Another tells us that the art of progress is to preserve order amid change and to preserve change amid order. These axioms help frame the increasingly public debate about the future of Canada?s oil sands. I hope to illustrate how Shell?s commitment and investments create positive progress that embraces change amid order in the oil sands. I?m going to spend a little time today to focus the spotlight on the future of the oil sands to help demystify Canada?s hydrocarbon energy future. To do that, I?ll identify the features of our future energy security, including three hard truths about global energy that drive Shell?s business imperatives. Then, it?s instructive to examine Canadians? current consciousness about oil sands sustainability.

Oct 1, 2009

By S. Simukanga, J. Masinja, P. A. Bepswa, A. N. Mwale

Screening is an important operation in dry and wet closed circuit mineral processing applications. Most of the operations have seen the benefits of using fine wet screens in primary grinding sections where the product is relatively coarse, and screens can handle the tonnage. Although many models are available, most of them are confined to dry and wet coarse screening applications. Most models do not give good predictions for wet fine screening. To facilitate model development, pilot plant tests were performed using a single deck Derrick Screen at aperture sizes of 45µm, 75µm, 106µm, and 150µm. Experimental data for a range of feed solids concentrations and flowrates was collected and used to calibrate the performance of the screen under the different operating conditions. The results showed that the performance of the screen deteriorated with an increase in feed solids concentration, and, similarly with an increasing feed flow rate. The percentage of fines carryover also increased with the reduction aperture size. The carryover was even more pronounced at higher feed rates and solids concentrations. A model was developed for predicting the performance of fine wet screening. Data from the test work was used to compare the actual and predicted results, and to calibrate the model. Additional independent data was used to validate the model and assess its limitations. This model will give an expected screen performance based on the initial feed conditions. It incorporates screen design parameters that allow for an estimation of a suitable screen size for a desired performance based on given feed conditions. This paper discusses; the results from the test work performed, the model development and its limitations.

Jan 1, 2016

By Theo. Koulomzine

"The property of Consolidated Central Cadillac Mines, Limited, consists of 1,103 acres formerly held by Central Cadillac Mines, Limited, and Wood Cadillac Mines, Limited. Both mines have been partly developed to depths of 565 and 1,000 feet respectively, and from 1939 to 1943 they produced gold, with small amounts of silver and tungsten, having a total value of $2,208,528 from 377,489 tons of ore. The average grade of the ore was $5.85 a ton . Less than 10 per cent of the ore hoisted was discarded by sorting. New development work, carried out since the former Wood property has been purchased by Central Cadillac, has shown that the tonnage indicated by mine workings and diamond drilling exceeds 2,000 tons per vertical foot.The property lies between the claims of Kewagama Gold Mines, Limited, and Pandora Cadillac Gold Mines, Limited, and straddles the Cadillac 'break' for a length of nearly 1 ½ miles. The main workings are 1 3/4 miles east of the well-known O'Brien gold mine.GEOLOGYOutcrops are very scarce, with none at all of the most important horizons, so that the general geology shown in Fig. 1 is deduced mostly from underground workings and diamond drilling. Fig. 2 is a vertical cross-section and Fig. 3 a longitudinal section through the ore zone.The ore lies within a belt of Blake River volcanics which is approximately 600 feet wide and is flanked on the north and south, respectively, by Cadillac and Kewagama sediments. All the formations have a nearly vertical attitude. The Blake River belt consists essentially of well sheared volcanic tulfs, but associated with these in the northern part are a number of bands of iron formation and the central part, to a width of 100 feet, is occupied by talc schists, making the Cadillac fault proper. Intruding the volcanics south of the Cadillac shear zone are dykes of two types- finegrained aplite or quartz albitite, and porphyry; both consist essentially of albite and quartz and are distinguishable only by the grain size. They have the general east-west trend of the formations they intrude."

Jan 1, 1954

By H. G. Harper, R. C. Hart

"The Mississagi quartzite is the basal formation of the Quirke Lake trough. As it is traced around the rim, a gradual change in dip is observed, as follows:Northwest corner 50 degrees south.Algom Quirke mine 34 degrees south.Quirke Lake 25 degrees south.Whiskey Lake 22 degrees west.Pecors Lake 25 degrees north.Algom Nordic mine 18 degrees north.Elliot Lake 11 degrees north.Pistol Lake 5-7 degrees west.Thus the apparent synclinal axis is a curving east-west line lying closer to the north limb than to the south. The axis appears to plunge west at about 5 degrees.The Huronian sediments lie on a basement of granites, gabbros, and volcanics. Diamond drill evidence indicates that this basement has a surface of peneplanation, and that the areas of soft basic rock have a smoother topography than the granite. For the most part the orebodies at the Quirke and Nordic mines overlie a basement of soft basic rock.The Mississagi formation is the host rock of the deposits, and its primary structures are suggestive of the conditions under which the conglomerate beds were deposited. Cross-bedding is common, although normal bedding varies from thick to thin to essentially lacking. Grain gradation is not common. Where coarse and fine grains occur together, the coarse tend to be more rounded than the fine. These features are characteristic of shallow-water deposits, laid down above the lower limit of wave action. Therefore, the quartz-pebble conglomerates probably represent ancient water courses, bays, beaches, and bars.The causes governing the creation of the trough can only be conjectured, but there is evidence that both subsidence and compressive stresses played active roles. Drag-folds in argillite beds near Whiskey Lake indicate compressive stress. On the other hand, gentle crumpling in thin-bedded limestones on Quirke Lake is probably due to pre-induration slumping and folding. If strong compression had been widespread within the trough, one would expect drag-folding and shearing of the incompetent beds to be more general. Two large-scale, fold-like structures were mapped by Collins, but their axes do not parallel the trough axis, and they are therefore not related to the major structure."

Jan 1, 1949

By Shuo Zhang, Wenying Liu

"In dump leaching, the efficiency of metal extraction from ores is strongly influenced by the mechanisms of fluid flow. Particle size distribution acts as a fundamental parameter in the determination of fluid flow properties in packed ore beds. In this study, we investigated the particle size distribution in dump leaching by using image analysis technique. The results showed that the particles in the dump varied from smaller than 2 cm to larger than 200 cm in diameter. P80 was calculated to be 200 cm, which was significantly higher than the historical data used by the operation. P25, P50 and P80 were found to increase non-linearly with increasing depth towards the toe of the dump, suggesting the segregation of fine and coarse particles. The image analysis results were verified by applying the rock fragmentation models. The model with the Swebrec function was found to be in better agreement with the image analysis results. Future research will investigate the effect of particle size distribution on the behaviour of fluid flow.INTRODUCTION Fluid flow plays an essential role in the extraction of valuable metals using heap/dump leaching (Amos et al., 2009). The rates of the chemical leaching reactions and microbial activities determine metal concentrations in the leachates and therefore the efficiency of the metal extraction. The reaction rates are influenced by two fundamental processes: transport phenomenon and reaction kinetics (Bouffard & Dixon, 2001). The transport phenomenon refers to the percolation of fluids through channels and pores in a packed ore bed, which carries lixiviants and reaction products to/from ore surfaces by convection and diffusion. The percolation rate of the leaching solution is determined by the hydraulic conductivity of the packed ore bed, which is a function of the permeability and the degree of saturation (Guzman et al., 2008). Permeability, an intrinsic property of a packed ore bed, is strongly influenced by the particle size distribution of the ore grains (Bouffard & Dixon, 2001). Hence, the objective of this study was to investigate the particle size distribution in dump leaching."

Jan 1, 2017

By T. Donkin, B. Patterson, M. I. Guthrie, J. T. Ross

"The interest in the use of sensor-based particle ore sorting has increased significantly with the recent advances in the sorting technologies and higher capacities per unit. This technology has the potential to provide great value in processing lower grade ores from the mine whilst delivering higher grades to the mill as well as in upgrading waste rock into ore. Typically, the focus is on the amenability of the ore to ore-sorting and associated reductions in the consumption of energy, water and consumables. However, layout has a significant impact on the installed cost of a concentrator and the layout impacts from fitting an ore-sorting circuit into the concentrator plan need to be carefully considered. This paper examines layout considerations that play an important role in ore sorting projects. These include additional crushing and screening requirement, transportation of the rejected material back to the waste stockpile (mine fleet requirements) and effects on concentrator footprints.INRODUCTION Ore sorting has been practiced throughout history with an early report by Agricola in 1556. Metallic and non-metallic minerals were extracted from rocks by laboriously breaking them with hammers and picks and hand-picking selected material with higher grade off a table. The concept has not changed but the sorting technology has evolved significantly over the last 20 years. Ore sorting is usually a dry process in which a portion of the material is rejected based on mineral properties and/or grade. The methods used for sensing ore particles cover a large range of physical properties. A variety of sensors are available that differ on the discrimination technique that is used, which include: photometry, radiometry, conductivity, magnetism, microwave, X-ray transparency: X-ray transparency and luminescence and UV fluorescence (Sivamohan and Forssberg, 1991; Wotruba, 2006). There are two main ore sorting techniques: particle ore sorting and bulk ore sorting. According to Nadolski et al (2018), the potential for sorting is determined though analysis of grade heterogeneity within the orebody (greater heterogeneity represents more opportunity to add value to a project) at the scale of the intended sorting unit size."

Jan 1, 2019

By Adam Turcotte

Mining operations consume a considerable amount of energy, and while reduced energy consumption is desirable, it is not always clear how to achieve this goal. Understanding the opportunities to optimize energy consumption is crucial, and the key to understanding is visualization. One option is the Sankey diagram, which has been used for over 100 years to visualize the flow of energy, materials, or cost through various processes. However, there are drawbacks to this approach that must be addressed. In a Sankey diagram, each flow is represented by an arrow possessing a width proportional to the magnitude of the flow it represents. The diagrams show input flows, how energy is converted and into what form, and also output flows. As per the first law of thermodynamics, the total energy output is equivalent to the total energy input, so any energy that is not transferred to another process is considered to be wasted. These waste flows are depicted in Sankey diagrams and make it straightforward to associate energy sources, sinks and waste flows. Unfortunately, Sankey diagrams do not convey all information required to support practical decision making for redirecting individual energy flows. Based only on a Sankey diagram, it may become evident that a significant flow of waste heat is of the appropriate grade (temperature) and volume to meet an on-site heat demand currently being met with paid-for, possibly carbon intensive fuel. However without augmenting the Sankey diagram with 3D spatial, true geometric analysis, the practicalities of the concept or idea may not be fully appreciated. Another issue with a Sankey diagram is that the magnitude of the energy flowing between processes may have temporal fluctuation or variability on different timescales (diurnal, seasonal, interannual). Currently, Sankey diagrams only provide a static picture of energy conversion and consumption, so that, for example, 4 separate diagrams could have to be prepared for each season. A new energy flow visualization technique which we have called Sankey Trees has been developed. Process locations are defined within a 3D model of the site being studied, and the magnitude of the flow between each pair of processes considered is replaced with a time series. Branches of sustained and diminishing flows are represented through variation of the geometric properties of the branches of the trees. These branches are animated to indicate the direction of flow, and branch joints are used to indicate that a process is transporting one form of energy to multiple processes.

Aug 1, 2013

By R. W. Lawrence

Sulphide is an effective reagent in the precipitation of base metals for both metal winning and environmental control. BioteQ Environmental Technologies Inc. has successfully demonstrated in industrial plants that biogenic sulphide reagent can be generated cost effectively and used to win metals such as copper, zinc and nickel from low-grade leach solutions and wastewater. Commercial plants in which sulphide reagent is used to produce high quality treated effluents for discharge directly to the environment are also in operation. Operations utilizing biogenic sulphide reagent for copper recovery from acid drainage and low grade leach solutions are discussed, including those at Bisbee, Arizona, commissioned in 2004 and at the Dexing mine in China, scheduled for commissioning in 2007. In addition, a new application of BioteQ&apos;s technology for the recovery of copper from gold-cyanide solutions, and the regeneration of cyanide, utilizing biogenic sulphide in place of chemical sulphide reagents in the SART process is described.

Jan 1, 2007