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By D Marshall

The sub-level blasthole benching method of mining has been proved to be economical at Willroy Mines. How-ever due to the nature and attitude of the wall rock, this method is susceptible to serious hanging-wall dilution of the ore. Attempts to solve the dilution problem by various means were not satisfactory until long Stressteel bars were employed as rock bolts. The adoption of this de-vice does not require any special skill, and has become routine in the under-ground operation. Since the inception of this method, the dilution of the ore has been greatly reduced and the ov1!r-all costs of controlling this dilution are much lower. INTRODUCTION T HIS is a report describing the successful use of long Stressteel bars as rock bolts in preventing l1anging-wall failure and consequent dilution in open stopes. Willroy Mines Limited is located (Figure 1) near the town of Manitouwadge, Ontario, approximately l1alf-way between Sault Ste. Marie and Port Arthur.

Jan 1, 1963

By R. I. Iacobescu, Y. W. Chiang, A. Van Audenaerde, R. M. Santos, T. Van Gerven, P. Knops

In this work, we explore a novel mineral processing approach using carbon dioxide to promote mineral alterations that lead to improved extractability of nickel from olivine ((Mg,Fe)2SiO4). The precept is that by altering the morphology and the mineralogy of the ore via mineral carbonation, the comminution requirements and the acid consumption during hydrometallurgical processing can be reduced. Furthermore, carbonation pre-treatment can lead to mineral liberation and concentration of metals in physically separable phases. In a first processing step, olivine is fully carbonated at high CO2 partial pressures (35 bar) and optimal temperature (200 °C) with the addition of pH buffering agents. This leads to a powdery product containing high carbonate content. The main products of the carbonation reaction include amorphous colloidal silica, chromium-rich metallic particles, and iron-substituted magnesite ((Mg1- x,Fex)CO3). Carbonated olivine was subsequently leached using an array of inorganic and organic acids to test their leaching efficiency. Compared to leaching from untreated olivine, the percentage of nickel extracted from carbonated olivine by acid leaching was significantly increased. It is anticipated that the mineral carbonation pre-treatment approach may also be applicable to other ultrabasic and lateritic ores.

Jan 1, 2014

By B. S. Prosser, K. G. Wallace, A. Akansobe

"This paper describes a ventilation project at the Wassa gold mine in Ghana. Golden Star (Wassa) (GSWL), a subsidiary of Golden Star Resources, owns and operates the mine. Golden Star holds a 90% interest in GSWL, while the Ghanaian Government holds the remaining 10% ownership, earning a 5% royalty on the gross revenue of GSWL’s gold production. Construction of the underground mine began in mid-2015 and pre-commercial production started in June 2016. Commercial production from the underground mine was achieved in January 2017. This paper describes the ventilation studies performed to support the initial development and production at the mine. The initial ventilation design included four, parallel surface exhaust fans. Future designs will include booster fans, new primary fans, and additional connections to surface. The paper describes the long-term ventilation planning goals and expectations as the mine achieves a production of 4,000 tpd with truck haulage to surface.INTRODUCTIONThe Wassa Gold Mine is located in the southern portion of the Ashanti Greenstone Gold Belt in Ghana, northwest of Tarkwa as shown in Figure 1. The mine has been in production as an open pit since 1998, with some minor disruptions, but the surface minable reserves have become exhausted and the mine started a transition to an underground operation in 2015. The underground mine was initially developed with twin decline accesses extending from the base of the open pit to the mining areas. The mining method selected was sub-level open stoping with cemented rock backfill. The original production level for the mine was 2,500 tpd with ore and waste transported by trucks hauling in the ramps to surface. In 2017 the production goal was set to increase to approximately 4,000 tpd. This resulted in an increase in the truck haulage fleet in addition to a significant increase in ventilation requirements. This paper describes the ventilation upgrades at the mine as it transitioned from a surface to an underground operation and the adjustments the ventilation system needed to make in order to accommodate a significant increase in production"

Jan 1, 2019

By Allan A. Este, Bruce Arthur

"Rio Algom's Stanleigh Mine and Mill Operation Was' officially started up in August 1983. In September 1982, Rio Algom contracted Estonix International Inc. from Lively, Ontario, to develop and implement two innovative programs: (1) Work Renovation Planning, and (2) Systems Performance Training. This paper deals with the development and implementation of these two concepts relative to the plants technology from start-up to present and the exceptional results achieved. This paper discusses how a small but motivated workforce resulted in the smooth transition from startup to full production. It also deals with how these concepts were applied elsewhere in the organization which permitted a successful transition and downsizing of the over-all operation.IntroductionRio Algom Limited produces uranium in Elliot Lake, Ontario. In the late 1970s Rio Algom entered a contract with Ontario Hydro to supply uranium from its Stanleigh property, which had been idle since 1960. The mine was subsequently upgraded, and a new modem mill was designed and built, commencing operation in 1983.From then until September 1990,Rio Algom had three producing mines and mills in the Elliot Lake area. Quirke mill, with a capacity of 6350 tonnes per day, operated continuously from 1968. The Panel mill with a 3000 tonnes per day capacity, operated since 1979. Stanleigh mill continues to operate under long-term contracts, although at a production rate about 25070 lower than its rated capacity of 5000 tonnes per day.Both the Quirke and Panel mills, although not entirely similar, were conventional uranium mills utilizing crushing, grinding, leaching and ion exchange. As such, and in keeping with the traditional management style, there was a rather large mill operating workforce, which utilized a line-of-progression job classification system."

Jan 1, 1993

By Pierre Sauvé, Alex Makila

"The Camflo stock of porphyritic quartz syenite is an irregular pipe-like body 200 metres in diameter injected along the axial plane of an E-W trending F2 fold, near the contact between the. Kewagama and Malartic groups. The stock plunges 55° to the NE, almost parallel to the fold axis. The stock, exhibiting pervasive, weak cataclasis with numerous, locally auriferous quartz veinlets, is cut by minor faults striking WNW and dipping about 45°NE.Two types of gold ore are distinguished at Camflo: ""porphyry"" ore and ""fault zone"" ore. ""Porphyry"" ore, accounting for 90% of the gold produced, forms wide zones within the stock. The zones are irregular in shape but tend to be oriented E-W in plan view (on a horizontal plane) and are elongated paraliel to the plunge of the stock. These zones are more abundant in the northern part of the stock. Differences between ore and barren porphyry are not obvious. ""Fault zone"" ore occurs outside the stock along minor faults, particularly in differentiated sills offer rodiorite and felsic granophyre. Gold grade is roughly proportional to the pyrite content which in turns depends in part on the original magnetite content of the host rock. Although both types of ore show some correlation between Au and S, the Au/S ratio is considerably higher in porphyry ore.The bulk of the gold is in quartz syenite and in felsic granophyre, the most brittle lithologies at the mine. Presumably, the vertically continuous, pipe-like stock, made up of shattered rock, provided the main channelway for the ascending mineralizing solutions."

Jan 1, 1990

By K. W. Major

"This chapter outlines the organization of mine/ mill complexes in Canadian mining companies. Many factors unique to the Canadian mining industry will affect the design of the organization in the future: geographic location, the size and the type of orebody, etc. Mining companies cannot choose where new operations will be located, that is dictated by the location of the orebody. New mines are seldom started near established communities. Rather, the towns usually grow up near the mines. The remoteness of most Canadian mining operations has caused severe problems in attracting and/ or retaining all levels of employees. This means that training has a high priority within each operation.Another factor affecting mine/ mill organizations is the size of the operation. Larger operations generally require more departments and increased specialization to manage equipment and manpower effectively. Thus, for mine/mill complexes, organizational charts are less standardized than in other industries. It is often necessary to organize around the work force rather than develop a chart and then acquire the trained personnel to fill the diagrammed positions.The information presented in this chapter has been derived from the responses received from a survey of Canadian mining operations.Principles of OrganizationOrganization can be defined as deployment of personnel to accomplish definite goals. In the mining industry, the major goals are typically the projected number of tons and grade of ore mined on a daily, weekly, monthly and yearly basis. Organizing involves establishment of authority relationships with provisions for both vertical and horizontal co-ordination within the company structure. Vertical co-ordination is the delegation of responsibility and communication of goals and reporting of progress between the supervisor and subordinate. Horizontal co-ordination is communication between departments at positions of equal authority to determine methods of achieving predefined goals. The organization structure must reflect the objectives and plans of the company, and must clearly define areas of authority.Two criteria for effective organization are departmentalization and manpower planning."

Jan 1, 1989

By S. Banisi, J. A. Finch, A. R. Laplante

"A technique for on-line simultaneous estimation of gas and solids holdup (volume fraction), based on a combination of conductivity and pressure difference measurements, is proposed and tested in a laboratory flotation column (10cm in diameter and 447cm in height). Fundamental concepts underlying this technique and the effect of relevant parameters are discussed. In the studied range, 3-30 %v/v gas holdup and 2-18 % v/v solids holdup, experimental results showed good agreement between the estimated and actual holdup values (as determined by an isolating technique). The relative accuracy of the solids holdup estimation increased when solids density or solids concentration increased. Frequent re-calibration of pressure transducers was found necessary for accurate phase holdup estimation.IntroductionGas holdup is a key parameter in controlling the performance of flotation columns. For example, flotation rate is affected by bubble size and gas rate both of which, in turn, affect gas holdup. Moreover, gas holdup also determines the slurry residence time which indicates a direct influence of gas holdup on recovery.Gas holdup determination has been the focus of many studies (e.g., Castillejos, 1986; Marchese et al., 1992). Some of the techniques which have been used are given in Table 1."

Jan 1, 1994

By R. W. Boyle

"The concept of using chemical methods in prospecting dates back at least to the middle of the 16th century. Modern methods of geochemical prospecting, however, based on secondary haloes and utilizing trace-element techniques, were first practised in the U.S.S.R. and the Scandinavian countries in the 1930's. After 1945, methods based on soils, stream sediments and vegetation were rapidly developed in the U.S.A., the United Kingdom, Canada, France and other countries.The modern methods of geochemical prospecting owe their rapid development in the 20th century to the following:1.-Recognition of the primary and secondary dispersion haloes and trains that are associated with all mineral deposits. 2.-Development of accurate and rapid analytical methods utilizing the spectrograph and the various specific sensitive colorimetrie reagents, especially dithizone. 3.-Development of polyethylene laboratory ware of all types and the development of resins. This permitted greater freedom of field analyses and reduced the incidence of contamination.4.-Development of gas chromatography. This permitted the rapid and accurate determination of hydrocarbons in petroleum prospecting.Future research in geochemical prospecting should be focused on the following tasks: 1.-Definition of geochemical provinces and their relation to mineral deposits. 2.-Development of methods for discovering large low-grade deposits. 3.-Development of methods for discovering deeply buried deposits. 4.-Further development of methods to outline primary haloes. 5.-Eiucidation and formulation of techniques to relate the size and intensity of anomalies to the grade of the deposits. 6.-Development and refinement of biogeochemical methods, especially those based on indicator plants, chlorotic or toxic effects, and microbiological techniques. 7.-Definition of the types of primary and secondary haloes associated with accumulations of oil and gas."

Jan 1, 1967

By R. L. Dunsmore

Introduction If one had been called upon to describe petroleum oil refining seventy-five years ago, he could have acceded to the request quite satisfactorily in about fifteen minutes. Fifteen years ago, an hour and a half would have been sufficient to give a general idea of oil refining, and of the equipment used for this purpose. Today, so extensive has been the research into all phases of the refining and manufacturing of petroleum products, and so rapid the strides in improvement in technique and equipment, that I doubt if a week would suffice to give an adequate outline of ail the ramifications of present-day oil refining. I propose to only 'hit the high spots', dealing particularly with the equipment and methods employed at the Imperoyal refinery, which you are to visit. Crude oil, the refiner's raw material, contains essentially only two elements, hydrogen and carbon. These are not present in the free state but are combined in various proportions as 'hydrocarbons'. A given crude oil is not made up of just one hydrocarbon, but of myriads; some solid, others liquid, and still others gaseous at atmospheric temperature and pressure, ail dissolved one in the other. Moreover, the nature and the relative amounts of the several hydrocarbons vary very considerably in crude oils from different sources. That is, a 'crude' from Oklahoma will contain hydrocarbons not present in crude from Mexico, and is different again from the Venezuela crude. Not only this but oil in a certain well in, say, Peru may be differently constituted from that in a well half a mile distant from it.

Jan 1, 1931

By Patrick S. Hudd

Traditionally in hard rock mining, large diameter raise boring was thought of as 3.04 metre or 3.66 metre diameter holes 300 metres deep. Mine and ventilation engineers were challenged to design systems either incorporating such holes, or slashing and modifying to suit. Now, 5.49 metre diameter holes up to 1,000 metres deep are being excavated. The ability to pilot and ream such holes not only creates new options for mine engineers in mine ventilation system design, but also creates new opportunities in mine access. By combining holes of this diameter with the ability to accurately drill long pilot holes within the diameter of the pilot hole through the entire length of the hole, borehole hoisting systems are now fully capable of being main production or service accesses for mines. This paper will review the present day capabilities of large diameter raise boring, potential applications for such excavations and some considerations for companies contemplating using large diameter raise boring in their operations

Oct 1, 2010

By W. E. Oching, M. M. Ghomshei

Attracting and retaining workers in mining industry has become an uphill battle to many mining companies. As workers with significant experience retire, it is getting more difficult to attract not only new workers but also top talent to the mining industry to replace professionals exiting the workforce. To make matters worse, students’ enrolment in the post-secondary mining programs in Canada and USA is continuously declining year after year for reasons not directly linked to job market. This raises a question of how can the future needs of mining be met? This paper focuses on avenues for collaboration of industry and educational institutions to meet the current and future needs of mining. It provides effective approaches that mining institutes can engage with program advisory committees, role of the mining industry in supporting both faculty and students, how to harness the benefits of diverse workforce in the country and use of innovative technologies to attract young workers in mining. This work presents Human Resources (HR) professionals with tools that they can use to hire and retain skilled workers with strong interest to work in the mining industry. It also provides HR professionals with an opportunity to re-evaluate their restructuring practices during economic downturns as they reduce number of employees on temporary or permanent basis. The paper stresses the need of working together of the mining stakeholders including mining industry, academic institutions, First Nations’ communities and provincial(state) and federal governments to meet the current and future demands of mining as the industry experiences shortage of labour and low students’ enrolment in post-secondary mining programs. It is shown that mining educational institutes can enhance their programs and recruitments through establishing a better communication with all stakeholders. This communication can be facilitated by creating a national advisory board, to work with all mining programs at the national level for sustainable mining.

Jan 1, 2023

By M. Mohan Rao

A Sievert ' technique was used. The few determinations made on 10 per cent and 20 per cent V alloys did not show any deviations from Sieverts' law up to I>N2 = 1 atmosphere. The same held true for alloys of 0.2 per cent Ti. Nitrogen absorptions in Fe-Ti alloys, containing from 0.50 to 0.77 per cent Ti at 1,600°C, follow Sieverts' law at low PN2 values, but, due to the formation of a delta titanium nitride phase, deviate from this law beyond critical values of PN2? There is evidence that this phase is Ti1.1N. The behavior observed can be described by the followmg equations: Ti,.,N(o) = 1.7Ti + N K = (fT; ? % Ti)1?7 (f;;.? %~_) = 0.0020 K = fN. %~ = 0.042 '\)-:>N 2 I NTRODUCTJON Nitrogen's solubility in liquid iron-vanadium alloys was investi-gated briefly by Brick and Creevy ( 1), and more extensively by Kash-yap and Parlee (2) and by Pahlke and Elliott (7). Nitrogen's solubility in liquid iron-titanium alloys

Jan 1, 1963

By H. L. Cheng, C. H. B. Leitch, C. T. Hood, A. J. Sinclair

"Epithermal Zn-Pb-Cu-Ag-Au quartz-carbonate-barite veins at the Silver Queen mine near Owen Lake, west-central British Columbia, are hosted by Late Cretaceous Tip Top Hill andesitic volcanic rocks. The veins form a rectilinear northwest-northeast pattern that differs slightly from regional structural trends. The main northwest-trending veins are oriented very close to the trend of regional northwest faults, but the crossing veins tend to be more east-north-easterly (070 degrees)compared to a regional north-easterly trend (040 degrees). The character of the veins suggests they are extensional features formed by dextral slip related to Paleogene oblique subduction, or intrusion of magma at depth, or both.In detailed exploration at the mine, the veins cannot be modelled as simple tabular sheet-like bodies. Instead, they are complex structures that divide and rejoin, forming multiple veins or stringers, or are found in shear zones as replacement features with quartzsericite- clay-carbonate-pyrite alteration haloes of variable width that make definition of vein margins and correlation from hole to hole ambiguous. In addition, individual veins within each of the main structures have en echelon characterboth along strike and down dip.Geological and assay data must be carefully studied to define the margins of these complex veins before any estimation of ore reserves may be made. Where multiple veins occur in a section, ore/gangue mineralogy, assays, character of wallrock alteration, and thickness of vein and mineralized hangingwall, median and footwall zones must be used to evaluate continuity of mineralized structures. Well-defined sections are projected into areas of increasing complexity. Once the vein boundaries are defined, metal concentrations, important metal ratios(Au/Ag, Pb/Zn, Cu/Zn), and true thicknesses of the vein provide the basic data for reliable ore reserve estimation."

Jan 1, 1991

By T. Feldmann, G. P. Demopoulos

The feasibility of chloride leaching processes depends on interfacing them with cost-effective HCl regeneration technologies. This paper summarizes the most important findings of research conducted in the past 3 years concerned with a novel process to regenerate high-strength HCl from concentrated CaCl2 solutions at temperatures below 100°C, via reaction of CaCl2 with H2SO4 resulting in the formation of calcium sulfate phases (gypsum, a-hemihydrate or anhydrite). From constant supersaturation semi-batch experiments in pure solution it was found that the crystal growth rate of hemihydrate, and hence the particle size, was influenced by the rate of reagent (Ca2+, SO4 2-) supply to the reactor. Additionally, growth studies of DH in presence of impurities (K+, Mg2+, Sr2+, Ba2+, Fe2+/3+, Al3+, La3+, Y3+, F- and PO4 3-) showed that specifically Sr2+ and PO4 3- are taken up during crystal growth. Furthermore, it was found that decreasing water activity (via different HCl/CaCl2 concentrations) and increasing temperature reduce the metastable life-time of DH and HH by increasing the phase transformation speed. The DH/HH transformation was identified to be dissolution-precipitation based, while HH to AH is a topochemical process. Finally, continuous experiments on bench scale are underway to confirm the feasibility of the process to obtain super-azeotropic strength HCl with up to 9 mol/L (~30wt.%) from 5 mol/L CaCl2 (~40wt.%) solution.

Jan 1, 2014

By I. S. Thompson

"The discovery of low-grade copper-silver mineralization near the town of Tipperary, Ireland, by Gortdrum Mines Limited was the result of reconnaissance geological and geochemical exploration followed by target delineation from induced polarization surveys.Initially, orientation studies at the Tynagh lead-zinc orebody showed that such deposits could be readily detected in stream sediments and soils using cold extraction analysis for total heavy metals. Numerous areas showing stratigraphical and structural similarities to Tynagh were then selected for reconnaissance geochemical prospecting.The Gortdrum deposit was detectable through the presence of anomalous metal values in stream sediments 3,000 feet downstream; soil sampling indicated an area of 2,000 by 700 feet containing 2 Yz to 20 times background cold-extractable metal values. Induced polarization surveys defined the dimensions and attitude of mineralization.Drilling to date has outlined (under 10 to 20 feet of till) low-grade copper-silver mineralization within Lower Carboniferous limestones and shales which have been faulted against Devonian sandstone. Mineralization ex-tends from surface to depths of 250 to 450 feet and consists of bornite-chalcocite-tetrahedrite and some chalcopy-rite in altered limestones and intrusive dikes.The deposit is geologically analogons to the Tynagh and Silvermines orebodies, but in contrast exhibits a predom-inant structural control. Provisionally, it is postulated that mid-Carboniferous folding and faulting produced the pre-mineralization high porosity via recrystallization, shearing and brecciation. Subsequently, hydrothermal solutions from the west, with a probable eommon origin to the volcanic dikes, were introduced along the fault planes. Although syngenetic causes cannot be exempted, the field relationships favour an epigenetic origin."

Jan 1, 1967

By N. M. Steven, J. M. Moore, J. L. Kuyper

Abstract - Mineral exploration and research has led to the identification of four types of tungsten mineralization in the NE-trending, largely ensialic, inland branch of the late Proterozoic/early Paleozoic Pan-African Damara Orogen. The mineralization (mainly scheelite) occurs in a terrane (the Central Zone) that is characterized by multiple deformation, greenschist/amphibolite-facies metamorphism and numerous peraluminous S-type granitic and pegmatitic intrusions. The four major types of scheelite mineralization are (in ascending stratigraphie order of host rock): (1) thin (5 cm to 2 meter) quartz+ plagioclase+ diopside ± scapolite cale-silicate granofels with finely disseminated scheelite (scheelite-bearing granofels; SBG) developed as discontinuous intercalations within the cale-silicate rocks of the Khan, Spes Bona, Oberwasser and Kuiseb Formations (Nosib and Swakop Groups); garnet+ pyroxene ± vesuvianite + scheelite ± fluorite replacement skarns hosted by Okawayo, Karibib and lower Kuiseb Formation marbles in the aureoles of late tectonic, unmineralized leucogranites; metaturbidite-hosted scheelite- (and possibly wolfrarnite-) bearing tourmalinites, both stratiform and crosscutting, in the Kuiseb Formation located in the 'cleavage fronts' of late tectonic granitoids; scheelite-bearing vesuvianite +quartz+ garnet skarnoid rocks (several hundred meters in length) in the calcareous metaturbidites of the upper Kuiseb Formation. These scheelite occurrences were discovered by the follow-up of a large number of tungsten anomalies located during a regional stream sediment sampling program. Detailed mapping, ultra-violet surveys and rock sampling proved to be the most effective surface exploration techniques for locating mineralization; soil sampling and geophysics were of almost no use. The largest, continuous scheelite-bearing skarn of economic interest, Otjua, has a drill-indicated reserve of 250 000 tonnes at 0.53 wt% W03 and 8 wt% CaF2.

Jan 1, 1994

By D. Sagara, V. G. Makhado

"A model based control strategy was implemented at Loulo Gold Mine in Mali, to stabilise the thickener underflow stream density. This stream acts as the feed to the leaching circuit. pH control of the leaching circuit was integrated with the model-based controller due to slow process dynamics that are not suited to PID control. The controller performance was quantified over a period of 6 months, and was compared to the performance before implementation. The model based controller reduced process variability for both thickener underflow density and pH considerably, and resulted in a reduction in flocculant and lime consumption of 9.32 and 6.55%, respectively. INTRODUCTION Reagent consumption in gold processing plants significantly contributes to the total operational costs. In a typical Carbon-in-pulp (CIP) circuit, the reagent consumption associated with leaching, adsorption, elution and regeneration contribute to approximately 15% of the total operational costs (Stange, 1999). At Loulo Gold Mine, the reagent consumption associated with leaching, adsorption, elution and regeneration contributes to 6% of the total operational costs. As such, a reduction in reagent consumption will present a significant opportunity for savings on operating expenditure. Variability in feed ore characteristics results in continuous changes in steady state operating regions, which presents process control challenges as a result of the long residence times in some of the process units associated with gold processing plants. Overdosing often occurs in the presence of process variability to ensure safe operation and to maintain recovery targets. As a means of reducing reagent consumption and accounting for significant changes in the feed to gold plants, some of the plants have resorted to improving their process control strategies around their circuits. This paper focuses on the implementation of a model predictive based controller at Loulo Gold Mine on their thickener and Carbon-in-leach (CIL) tank to: •,stabilise the thickener underflow density, and •,the CIL tank pH."

Jan 1, 2017

By R. B. Paine, B. M. Wright

"Syncrude has entered a new era involving the use of pipeline slurries to convey oil sand to the extraction plant. Hydrotransport operations and base plant operations encounter vast performance differences when processing different types of oil sand. This paper describes the hydrotransport process, its history at Syncrude, methods of describing the source ore characteristic and plant performance. The use of this information within Syncrude and how it will be managed on an ongoing basis will also be described. IntroductionThe Syncrude Canada Ltd. site is located 43 km north of Fort McMurray, Alberta, on the Athabasca oil sand deposit. The Syncrude operation consists of mining, extraction, upgrading, utilities and other support facilities. The mined ore is sent to the extraction plant where water and solids are removed from the bitumen. The bitumen is then sent to the upgrading plants to be further processed into Syncrude Sweet Blend (a light sweet crude oil). Syncrude produced 73.5 Mbbls of Syncrude Sweet Blend in 1996 and produced 75.7 Mbbls in 1997. Prior to 1993, Syncrude moved ore from the pit to the extraction plant via four dragline / bucketwheel/ conveyor systems. These systems, supplemented by auxiliary ore crushers, satisfied the feed requirements of the extraction plant. Ore was conveyed to the control tower area and placed in the dump pocket via four radial stackers. Various blending scenarios occurred at this point, using feed from the four mining quadrants and from auxiliary feed crushers. Upon entering the extraction plant from the base mine, the oil sand passed through a series of tumblers where it was mixed with hot water and caustic. It then proceeded to one of four primary separation vessels where bitumen froth was floated off and the middlings and coarse fractions were recombined and sent to the tail oil recovery vessels, or TORs, for further processing."

Jan 1, 1999

By Wilson Pascheto

One of the main outcomes of a capital project is the reliability of a new plant, system or equipment. During 20 years of experience working in various capital projects for the mining industry, the author experienced failures which have caused significant losses to Owners, in many cases amounting to millions of dollars and almost jeopardizing entire projects. Often, failures were related to faulty design, shop fabrication and/or construction. Therefore, significant opportunities exist in the Mining Industry to improve the success rate of capital projects, improve on-line time at start-up, minimize the occurrence of unplanned maintenance due to equipment failures, and all this with positive contribution to health and safety. This paper presents some examples of failures and how they could have been prevented by proper Quality Assurance methodology. It also discusses some of the main challenges in the implementation of such methodology, including awareness of the Materials discipline and availability of trained Engineers.

Jan 1, 2015

By Z. X. Cui, X. D. Ma, L. Contreras, X. Jiang

The bath smelting process is one of the key techniques applied in the current copper smelting production, which includes bottom-blown and side-blown furnaces differently from the direction of gas injection. Liquid matte and slag form the bath in the smelting furnace. To better understand the fluid dynamic of the bath and further optimise the operational efficiencies in the smelting furnace, physical simulation of the bath in the horizontal cylindrical reactor was investigated. The mixing behaviour and wave motion of the bath in the bottom-blown and side-blown furnaces have been studied systematically. The mixing time is reduced with increasing gas flowrate and height of the lower layer, while it increases significantly with increasing the height of the upper layer. The wave motion in the furnaces can be suppressed with the presence of the upper layer, but the bath with a lower density generates higher wave amplitude. Overall, in comparison to bottom-blown mixing, side-blown mixing shows better mixing efficiency and lower wave amplitude. In addition, the plume eye and splash phenomena occurred in the bottom-blown furnace have also been studied. INTRODUCTION The bath smelting process is one of the principal techniques used in the current copper making industry. The bath smelting techniques have some advantages of high smelting efficiencies, low capital costs, low energy consumptions and reduced dust generations. From the direction of gas injection, the bath smelting techniques can be classified into five general types: (1) top-submerged blown, e.g. Ausmelt and Isasmelt; (2) top-suspended blown, such as Mitsubishi smelting; (3) top direct-to-copper smelting, such as Outokumpu smelting; (4) submerged side-blown, such as Noranda and Teniente smelting; (5) bottom-blown, such as Dongying Fangyuan bottom-blown copper smelting furnace (Schlesinger et al., 2002; Zhao, Cui, & Wang, 2013; Perez-Tello et al., 2018). In many metallurgical processes involving bath smelting situations, the objectives of agitation are to accelerate the bath homogenization inside the bath which makes a significant contribution to process efficiency and product quality. Extensive mixing studies have been performed for ladle refining and tundish associated to steelmaking processes through water physical models. Mixing time is the parameter used to quantify the efficiency of mixing in the liquid bath and the first empirical equation predicting mixing time was proposed by Nakanishi, Fujii and Szekely (1975). Later on, more systematic studies have been carried out on ladle mixing and researchers realized that the geometry of the vessel could also have a significant impact on mixing (Khajaviand & Barati, 2010). However, the investigations using ladles which are vertical cylindrical vessels, cannot be directly used in the study of mixing behaviour in horizontal cylindrical reactors. Understanding the fluid dynamics inside horizontal cylindrical bath smelter is useful from the industrial perspective. Recently fluid dynamics of horizontal cylindrical smelter related to copper smelting have been studied by the authors’ group (Shui et al., 2015a, 2015b, 2018a; 2018b; Xu et al., 2018, 2019).

Jan 1, 2019