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By Xiong Tong, Jiushuai Deng, Yingbo Mao, Lingyun Huang

Ammonium carbamate has been used as a reagent for the leaching of copper from the copper oxide ore found in the Honghe state, Yunnan province, China. In order to find the optimal conditions for the leaching of copper from this copper oxide ore,the effects of several processing parameters, including the concentration, time, temperature, particle size and stirring intensity have been investigated. The results of these optimization experiments showed that the leaching rate of copper reached up to 72.76% under the following conditions: liquid-to-solid ratio of 10:1, ammonium carbamate concentration of 2.5mol/L, leaching temperature of 45 °C, stirring speed of 300rpm, a reaction time of 1.5 h and 85% by weight thereof passes through a sieve having 0.074 mm.

Jan 1, 2015

By F. Czerwinski

Mechanically fragmented chips of an AZ91D magnesium alloy were transformed into a semisolid slurry within the Thixomolding® system. Microstructural analysis of a material at various processing stages revealed that the cold deformation of the alloy, experienced during chipping, led to the recrystallization and growth of equiaxed grains which were subsequently converted to the globular structures by melting the grain-boundary network.

Jan 1, 2004

By M. Choy, A. Kadiayi, E. Magdzinski

"Design of engineering controls to limit occupational noise exposure rely on accurate calculation inputs. Sound in mines can carry considerable distances. Mine ventilation engineers rely on noise propagation calculations to estimate silencer performance criteria for key mine fan installations that are often in proximity to occupied areas of a mine and can remain in service for decades. The blasted and rockbolted walls of hard rock mining tunnels have unique acoustical properties. Underground testing in an operating metal mine in Sudbury, Canada was performed and results processed to characterize noise propagation in mines, with the goal of improving the accuracy of noise calculations.INTRODUCTIONAs mine operators continue to improve and promote workplace safety, addressing noise at fixed infrastructure locations is observed as increasingly common. Underground fans are important to consider in this context, as they are typically loud, in proximity to occupied and sensitive workplaces, and operate nearly continuously. Predicting noise propagation from ventilation fans within underground mines has long been a challenge, with few available resources documenting acoustical properties as calculation inputs. Other factors in addition to rock face absorption properties include tunnel geometry and distance from the fan, which play critical roles in characterizing the noise level at any given point away from the fan. By understanding and establishing methods to better predict noise dissipation along underground mining tunnels, engineers can design noise controls with a greater degree of precision and confidence to effectively protect workers from over exposure to noise.This paper investigates classical methods of predicting reverberant room and direct field noise propagation. These prediction methods are then compared to noise measurements taken within the Fraser Mine of Glencore’s Sudbury Integrated Nickel Operations (Sudbury INO) Measurements were taken at a depth of ~881 m (2,889 ft), along an ~300 m (984 ft) long blasted hard rock mining tunnel. The noise along the mine tunnel resulted from the intakes of two 900 kW (1,200 hp) ventilation fans with a combined exhaust capacity of 300 m3/s (630,000 cfm)."

Jan 1, 2019

By Ron Zevenhoven

In Finland one opportunity for large-scale CO2 capture, utilisation and storage (CCUS) is CO2 mineralisation, i.e. mineral carbonation. A process route under development towards industrial application involves production of magnesium hydroxide or sulphate from serpentinite rock (serpentine = 3MgO·2SiO2·2H2O), followed by conversion either in a pressurised fluidised bed (PFB) reactor, giving magnesium carbonate, or in an aqueous solution process giving magnesium hydro-magnesites. Iron present in the rock is typically obtained FeO(OH). Results obtained with these process routes and progress towards industrial demonstration is addressed, process heat integration and operation on flue gases (without CO2 pre-separation!) being key features for economic viability. A process route utilizing calcium-containing slag by-product from iron- and steelmaking under development towards large-scale application is the so-called slag2pcc concept. It converts an industrial by-product into valuable material, reduces use of natural material and streams to landfills while binding CO2 produced by the process generating the slag. Using ammonium salts, calcium is extracted from steel converter (BOF) slags and subsequently carbonated in a two-stage aqueous process (at ambient temperatures and pressures). Precipitated calcium carbonate (PCC) is produced while regenerating the ammonium salt. Process performance and scale-up while guaranteeing a certain PCC quality are presented.

Jan 1, 2015

By Richard D. Moffett

The MineSight® Implicit Modeler arms geologists, engineers and surveyors with a better approach to 3D modeling. Use the tool to quickly retrieve a 3D wireframe from drillhole data and onscreen interpretation. Generate faster and more informed decisions to guide future work and improve reproducibility of results. Implicit Modeling is a mathematical surface fitting method that interpolates points to give a smooth and realistic fit. Control results by mixing planar, sectional and non-orthogonal polygons or polylines, as well as drillhole information to create solids or surfaces. The outcomes are particularly valuable to identify ore body trends, generate 3D contours of drillhole intercepts, or produce cut-off 3D maps. MineSight Implicit Modeler (MSIM) is fully integrated in MineSight?s robust and versatile suite of products, allowing you to interpret, interpolate and calculate while moving between applications. It connects seamlessly with the MineSight Torque SQL database, offering access to extensive filtering options. MSIM makes modeling much faster, allowing geologists more time to analyze data and test theories. The presentation will reveal how MSIM complements MineSight?s geomodeling workflow.

May 1, 2013

By Neo Molelekeng, Jocelyn Bouchard, Rebecca Monnapula, Martin Émond

"Xstrata Alloys – Eland Platinum concentrator (South Africa) has recently been commissioned and is now initiating a challenging optimisation program encompassing the entire operation. Process control improvements are key elements of the program and initial results have demonstrated how leveraging from current assets can bring significant improvements through overall reduction of variability. This paper gives a brief overview of the operations and details how Eland is striving to become a top tier leader with advanced regulatory control strategies recently implemented. Results reveal that what can be achieved in a standard control system (PLC or DCS) should not be underestimated as the first interventions led to a steadier operation of the primary ball mill circuit. Following the improvements, significant and sustained reductions of standard variation were observed for key process variables around their set-point: primary ball mill feed rate (72 %), rougher feed density (58 %), and rougher feed flow rate (47 %). A path forward has been identified to tackle further opportunities around the primary grinding circuit: water balance management, throughput optimisation as well as charge and power draw control.INTRODUCTIONThere are numerous approaches to mineral processing plant optimisation. As the benefits of determining the right reagent types, mix, dosage and addition points, or the proper charge of grinding media in a mill are fully appreciated, there is still nowadays some misunderstanding and misconceptions about process control in general and how it can contribute to the whole optimisation process. The confusion between the various disciplines involved, i.e. instrumentation, control system programming, automation and process control, certainly does not serve the best interest of the industry with this regard."

Jan 1, 2010

By K. Sakaguchi, T. Yokoyama

"In-situ rock stress measurement was carried out in the Kamaishi mine of Iwate Prefecture to quantify the variation of the shallow crustal stress field associated with the 2011 Tohoku-oki earthquake. Stress measurement was conducted by the Compact Conical ended Borehole Overcoring (CCBO) technique, which is one of the stress relief method. The CCBO technique is the one of the suggested method of ISRM. Measurement period is from 1991 to 2014. Main results obtained in this study can be summarized as follows.The direction of the maximum principal stress did not change much before and after the earthquake. However, the directions of the intermediate principal stress and the minimum principal stress of one year after the earthquake changed from those of before earthquake. Namely, the direction of intermediate principal stress was East-West horizontally, and the direction of minimum principal stress was vertically. This state of stress is reverse fault type and was maintained for three years after the earthquake.The magnitudes of principal stresses and the vertical stress of one year after the earthquake became more than the double before the earthquake. However, the magnitudes of the maximum principal of two year after the earthquake became smaller comparing with those of one year after the earthquake. Furthermore, the magnitudes of the intermediate principal stress and the minimum principal stress of two year after the earthquake became almost same as those before earthquake, and the vertical stress of two year after the earthquake became almost equal with the overburden pressure. And the magnitudes of three principal stresses of three year after the earthquake became the same level before the earthquake."

Jan 1, 2015

By A. J. Hyett

Due to the ongoing revolution in electronics and communications more cost-effective geotechnical instruments can be manufactured using digital technology. This new generation of digital instruments have embedded microcontrollers that provide highly accurate and reliable measurement of geotechnical behaviour in real world units that can be immediately interpreted. Digital measurements can be transmitted across existing mine-wide wireless communication networks, interfaced directly with infra-red enabled PDA?s or PC?s, and parsed to memory by low-cost data-loggers.

Oct 1, 2004

By Manouchehr Oliazadeh

Talc is used as a gelating, diluting, antimould and softening agent in the pharmaceutical industries. This article reviews efforts made for producing pharmaceutical grade talc from a mine located in the west of Iran, called Masoud Abad. Reaching to the pharmaceutical standards, was the principal goal of the talc beneficiation. Methods such as flotation and leaching were applied to eliminate the impurities. Considering to the negligible Fe content of the ore, the major impurity was calcium carbonate and to some extent dolomite. Depressants used in froth flotation were dextrine, quebraco and sodium silicate. Variation of collectors such as oil petroleum, paraffin, stearic acid were also used. After optimization of the effective parameters, followed by two stages of flotation (rougher and cleaner) acid leaching process was also applied as a complementary step to remove the impurities. CaO impurities in the sample was 11.63% which reduced to 1.03% after two stages of flotation, and finally reached to 0.03% CaO by leaching process. This figure is more lower than the world pharmaceutical standards (i.e. <0.6 % CaO). The highest recovery was 55% at the best conditions. Other impurities (i.e.As, lead, heavy metals ,?) which were at standard levels, confirmed by the authorized health organizations.

May 1, 2001

By Jerry M. Whiting, Neil J. Duncan

"Does Canada need a mining industry? Isn&apos;t it a chronically depressed collection of businesses that pollute the air and water and tear up the countryside? Wouldn&apos;t it be better if Canada&apos;s investors devoted their attention to high-technology endeavours, tourism, and other relatively pleasant tasks?Probably the answer to whether Canada needs a mining industry in the 21st century is to look at the real mining industry that is in operation today. The facts indicate that mining is a very important contributor to Canada. It has certainly encountered some challenging times during periods of recession, and it face s severe and continuing problems of cost and competition in world markets. However, uneconomic mines have been closed, others suspended, and productivity has risen dramatically with employment at 77 000, down from 101 000 in 1981. The country&apos;s metal and non-metal mines, metallurgical plants and semi-fabricated metals industries employed an estimated 378000 workers in 1986, and paid wages than any other sector of the Canadian economy. This effort resulted in the production of 60 different metals, non-metals and structural minerals valued at $13.5 billion.The trade aspects of the mining industry are of paramount importance. If there is a reason for this situation to change during the next century. it eludes the authors. Canada has the well-developed expertise to discover, evaluate, develop, operate and profit from existing and new businesses based in an enormous area endowed with a nearly unbelievable variety of mineral resources. Many countries throughout the world must rely on producers like Canada, if they are to maintain and/or improve their standard of living."

Jan 1, 1988

By A. J. Hyett

Due to the ongoing revolution in electronics and communications more cost-effective geotechnical instruments can be manufactured using digital technology. This new generation of digital instruments have embedded microcontrollers that provide highly accurate and reliable measurement of geotechnical behaviour in real world units that can be immediately interpreted. Digital measurements can be transmitted across existing mine-wide wireless communication networks, interfaced directly with infra-red enabled PDA?s or PC?s, and parsed to memory by low-cost data-loggers.

Apr 1, 2005

By Rolf Andreas Lauten, Adam Pratomo, Dani Ramdani, Helminton Sitanggang

A universal challenge for the mineral processing industry is the diminishment of high grade ores. Instead, low grade ores, sometimes also containing problematic gangue minerals is the reality. With lower head grades the industry has to put more effort into processing to maintain the output and achieve suitable recoveries. In an effort to reduce the impact of declining head grade, a biopolymer was evaluated as an additive in the gold leaching operation at Antam Pongkor in Indonesia. Laboratory testing revealed that biopolymer usage lead to an increased gold recovery without apparent negative impact on the other parts of the process. Further plant trials revealed both a recovery increase around 1.3% and higher throughput (9%) in the presence of the biopolymer. Some scenarios that can explain these findings will be discussed.

Jan 1, 2014

By J. O. G. Sanderson

THE Brazeau river is a relatively short foothills stream in western Alberta and its drainage area is limited to approximately 2,400 square miles. It rises near the head of the North Saskatchewan river, about two-thirds of the way from Banff to Jasper, and is confluent with the North Saskatchewan at a point about 40 miles north of Rocky Mountain House. It is not the purpose of this paper to describe the geology of all of this area. Only the central portion, which lies east of the outer limestone ranges and takes in the outer folds of the foothills belt, will be dealt with. This area is shown on Figure 1. A small portion of the area described lies in the drainage basin of Pembina river, which flows into Athabaska river. The area to be discussed may conveniently be termed the &apos;Brazeau area&apos;, since Brazeau is the name of the river basin referred to above, of an out-lying limestone range, and of the only large settlement or community in the region, the mining town Brazeau. One of the first Factors of the fur trading post of Rocky Mountain House in the early years of the nineteenth century was Louis Brazeau. Coal mining during the past 25 years, and more recently exploratory drilling for oil, have brought the district into some prominence. The Brazeau area was visited by D. B. Dowling for the Geological Survey of Canada in 1906 and 1907 (1). His traverses and reports dealt mainly with the Kootenay coal deposits. It is doubtful if he traversed the outer foothills area with which the present paper deals. His reports on rich coal deposits in the Bighorn Basin area attracted commercial interests, and in 1908 large tracts were leased as coal lands. James McEvoy mapped and studied the coal seams in that year, and G. S. Malloch, of the Geological Survey of Canada, made a complete survey of the whole of the Bighorn basin. His report (2), published by the Survey in 1911, describes the stratigraphical geology and names the formations. Further references to the geology of the district, mainly in relation to coal, are made by D. B. Dowling (3) and by J. S. Stewart ( 4). In the period between 1913 and 1920, the area was traversed by private interests in search of likely oil structures. A well was started in 1914 along the Saskatchewan river about 19 miles west of Rocky Mountain House, and drilling was undertaken by Imperial Oil, Limited, in 1921 at Coalspur.

Jan 1, 1939

By James R. Kuipers

Center for Science in Public Participation CSP2 ? Organized in 1997 to provide technical assistance to public interest groups on mining and water quality issues ? 80%of effort devoted to direct support of grassroots groups and tribal governments ? 20% of effort devoted to public-oriented education for public, tribal, state and federal regulators, and for industry ? Board represented by public interest groups, at large citizens, and academia ? Professional staff with experience from mining industry, academia and government ? website: www.csp2.org CSP2 Mission Statement The CENTER for SCIENCE in PUBLIC PARTICIPATION provides training and technical advice to grassroots groups on water pollution and natural resource development issues, especially those related to mining. CSP2 seeks to focus the debate on factual issues, as brought to light by its technical analyses, and whenever possible to seek consensus and win-win solutions. CSP2 also performs policy related work with federal and state regulatory agencies on the implementation of water quality, waste disposal, and mining reclamation regulations.

May 1, 2002

By J. P. Mogan, E. D. Dainty, K. Katsuyama

"The Volvo BM 861 U articulated truck is one of the few underground diesel units manufactured by an organization which shares the same corporate roof as the engine manufacturer. As a consequence, the unit has provided an opportunity for the characteristics of the entire system- turbocharged aftercooled engine, transmission and exhaust scrubber- to interact to minimize emission levels. The performance of the components of the system, as evaluated by full-scale dynamometer testing, is summarized. The over-all effect of the various innovations was a 38% reduction in the recommended ventilation level over that of the bare engine.IntroductionThe Mining Research Laboratories of Energy, Mines and Resources Canada is required, as part o f the certification service of the Canadian Explosive Atmosphere s Laboratory, to test the exhaust emissions of diesel engines, and to recommend appropriate amounts of fresh ventilating air to minimize the risks to health of underground personnel working with, or in the vicinity of, such diesel engines. Volvo BM AB of Sweden made application for the certification of the BM 861 U truck during a period in which EMR personnel were engaged in a number of research projects concerned with improving the environment in dieselized mines. One such avenue of research was the venturi or high-energy scrubber; as the BM 861 U was equipped with this type of scrubber , EMR and Volvo BM agreed to cooperate in a considerably more extensive investigation than would be normal for a certification application. The outcome of some of this research is summarized in this paper."

Jan 1, 1981

By Taisuke Sakakibara, Shinya Suzuki, Tatsuya Kato, Chiharu Tokoro, Kenichi Muto

Surface complexation using a diffuse layer model were constructed for arsenic (As(V)), zinc (Zn(II)) and silicate (Si(IV)) for aluminum hydroxide in the co-precipitation process. From experimental investigations using isotherms, zeta potential measurement and XRD analysis, it was confirmed that co-precipitation involved not only surface complexation but also surface precipitation. However, surface complexation was major mechanism for As(V), Zn(II) and Si(IV) removal under the target removal level of the Japanese effluent standard. In surface complexation modeling, exchange capacity of aluminum hydroxide was determined from specific surface area obtained from experimental measurement and site density obtained from reference. Surface complexation coefficients were determined by fitting the removal property and sorption isotherm obtained from co-precipitation experiments. These parameters were in agreement with the numerical parameters found by Karamalidis and Dzombak (2010) who reported a database of adsorption equilibrium constants for gibbsite. The surface complexation models constructed in this study were applied to neutralization process of an actual AMD treatment. Our model could successfully represent the pH edges for As(V), Zn(II) and Si(IV) in the neutralization of AMD.

Jan 1, 2015

By Tibor Horvath

Dust abatement is possible on bulk materials, whether conveyed or stockpiled. Minimum (ppm) quantities of chemical additives can efficiently and rapidly control dust of conveyed substrates with no effect on floatation chemistry. Top coating of large surface areas can control surface dust and wind erosion. Environmental and toxicity impact must be considered in any treatment, especially on areas with percolation runoff, leachates, or limited containment. The most effective dust control is preventing release of substrate fines rather than trapping and removing air borne dust. Techniques to prevent release of fines from conveyed substrates will be discussed. Dust control dynamics are a very complex combination of solid phase physical and chemical interactions between the substrate and the fines. ?Smart Technology? products permit dust abatement of stockpiled substrates and tailing fields with no environmental impact. Using ?Smart Technology?, the dust abatement products remain active and can re-seal damaged areas. Efficient, low environmental and toxicity impact, dust control will be demonstrated through case studies where these principals have been applied.

Oct 1, 2010

By H. C. Boydell

Introduction Situated in the district of South Lorrain, some 16 miles southeast of Cobalt, Ontario, and reached from that centre either by branch line of the T. & N. O. railway or by what, for a mining camp, is a reasonably good road, the Keeley mine, owned by the Keeley Silver Mines,&apos; Ltd., has had its history recorded by C. W. Knight (1). Silver was first discovered in South Lorrain, in Woods&apos; vein, on Keeley property, in 1907, and the Keeley mine has been described by Knight (2) and Bell (3). The total production to February 28th, 1930, has been 10,760,107 ounces of silver and 1,285. 434 pounds (weight) of cobalt.

Jan 1, 1931

By A. Taylor, M. Blanchette, J. Doucet

"A Z1600 Jameson Cell Test Rig was rented for test work at Vale’s Clarabelle Mill operation. This paper discusses the evolution of renting the unit for test purposes to owning the unit and operating it as a revenue generating process component. The paper focuses on three aspects of the Z1600 project; the initial rental and installation, the test work performed in the cleaning circuit, and the business factors which led to the unit being permanently incorporated into the copper circuit.INTRODUCTION Clarabelle Mill is located in Sudbury Ontario (approximately 350 km north of Toronto) on the southwest rim of the Sudbury basin a meteoric impact crater that is 62 km long and 30 km wide. The result of the meteoric impact was concentrated nickel (Ni), copper (Cu) and platinum group metal (PGM) ore bodies in the outer perimeter of the basin; described in more detail by Hanley (1957). Vale currently has seven operating mines in the Sudbury basin, from which nine distinct ore types are mined. Ores are also received from two QuadraFNX mines. Clarabelle Mill processes all of these ores for the Ontario Operations of Vale. The mill, commissioned in 1971, was originally built as one of four mills operated by then Inco Limited. Between the late 70’s and the early 90’s process changes were made to consolidate the Sudbury Operations milling processes into a single operating mill, Clarabelle Mill. In 1990, the SAG mill was installed resulting in peak mill throughput of 11.9 million short tons per annum (Mstpa), with typical throughputs of ~10 Mstpa. Mill average feed grades were 1.4% Cu and 1.2% Ni. During the resources boom, plans were developed to increase the mill capacity at Clarabelle Mill in stages to a final capacity of 13.5 Mstpa. The project known as the Clarabelle Mill Expansion and Recovery Project (CMERP) included expansion and reconfiguration of the grinding and flotation circuits. The first stage was a planned increase in grinding capacity with the reallocation of existing mills, the existing flotation capacity would be required to treat higher throughput until the new flotation circuit was constructed."

Jan 1, 2012

By A. W. Jolliffe

DESPITE the widespread occurrence of scheelite in Canada, domestic production of this strategic mineral is still quite insufficient to meet wartime needs. Two difficulties have invariably arisen in prospecting for or developing scheelite deposits: scheelite is a difficult mineral to identify, and secondly, its distribution is commonly so erratic that the value of a deposit cannot be determined without arduous and expensive methods of sampling and wet assay. Scheelite&apos;s property of fluorescing under certain ultra-violet lamps overcomes the first difficulty and is the basis for a quantitative method developed to overcome the second. It is found that, by use of an ultra-violet lamp, the value of many scheelite deposits may be accurately and speedily determined. The method requires neither elaborate apparatus nor exceptional skill on the part of the operator, and is most applicable to those deposits where the bulk of the scheelite occurs in fairly pure aggregates that are at least one-tenth of an inch across. It has been used in grading some two hundred scheelite-bearing veins in the Yellow-knife-Beaulieu region, Northwest Territories, and various occurrences in the Porcupine district, Ontario. The method requires the measurement of the total area of scheelite exposed in any reasonably large measured cross-section of a deposit. From the areal percent of scheelite so obtained, the tungstic oxide (WO,) content of that part of the deposit may be calculated by means of equations of simple derivation.

Jan 1, 1942