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By Michel Dostie

Un séchoir à vis chauffé par induction électromagnétique a été développé et implanté chez Mines Niobec pour le séchage d?un concentré de niobium. Ce séchoir a permis une réduction des émissions de poussières et des gaz à effet de serre de l?usine. Il offre une grande souplesse de contrôle, une meilleure efficacité énergétique et peut être utilisé pour le séchage de granulats, de poudres ou autres substances habituellement traitées dans un four rotatif ou à l?aide de vis chauffées par un caloporteur. Le principe de fonctionnement du séchoir est simple. Trois inducteurs opérant à la fréquence du réseau électrique assurent le chauffage des parties métalliques du séchoir, dont des vis qui servent à convoyer le matériel. Le contact du matériel avec les parties métalliques chaudes permet le transfert de l?énergie requise pour le séchage. La conception de ce type de séchoir requiert un équilibre adéquat entre les besoins associés au chauffage par induction et ceux liés au transfert de chaleur par contact et au transport du matériel dans le séchoir. Cette première implantation industrielle a nécessité des efforts de développements importants et une collaboration des différents intervenants. Une revue des principes de conception, des difficultés rencontrées et des performances obtenues sera présentée.

May 1, 2007

By D. B. Smith

DURING the summer of 1953, test work commenced at the Sullivan Concentrator with a view to the modification of filtration practice by the inclusion of wet cyclone classification of the lead concentrates, with separate filtration of the underflow and overflow products. Formerly, practice was conventional and the equipment employed comprised one 50-foot diameter thickener ?with the underflow routed via a 20-foot stock tank to two 8-foot by 12-foot Oliver filters. Heating of the filter feeds to 40° C. and the use of mechanical slappers on the filter drums ?have both been standard features of Sullivan practice for years. Both of these have been retained. Currently (February, 1956), lead concentrates are being classified into sands and slimes by 12-inch cyclones with the underflow, at 75 per cent solids, being fed to No. 1 Oliver filter. The overflow is thickened to 75 per cent solids and filtered separately by a No. 2 Oliver filter . The tonnage split is approximately two of underflow to one of overflow. The overflow contains 75 to 80 per cent of the total minus I 500 mesh slimes in the feed.

Jan 1, 1956

By S. J. van Rensburg

Competition for resources, including water and arable land, refocused attention on water and gold tailings management with respect to quantity and quality. MINTEK established and validated an "Advanced Leach Facility" to record kinetic leach information aimed at gold refractory sulphide ores. This facility was developed because of the need for additional leach process information to enable proactive decision making. Instead of focussing on optimised gold recovery only, the impacts of pre-oxidation methodologies were evaluated by considering key parameters, including cyanide speciation, reagent consumption, thiocyanate, arsenic, heavy metals, salt loads, water quality and residue stability. Results from oxidative leaching of a refractory gold ore employing oxygen, ozone, ultra-fine grinding, high shear and pressure oxidation are discussed. The relative cyanide and lime costs and environmental and sustainability effects associated with these technologies are briefly outlined.

Jan 1, 2011

By F. O. Verret

Several grindability tests were developed over the years to design grinding circuits or optimize existing operations. Each test has its own strengths and weaknesses and it is imperative to select the proper test procedure(s) to meet project deliverables and minimize the risk of a project. Pilot plant testing of large bulk samples historically constituted the traditional approach for AG or SAG design, but was gradually replaced by small-scale tests. Nowadays, conducting grindability tests requiring only a few kilos of material on several samples is a more typical approach to grinding mill design. This paper summarises the requirements and deliverables of various bench-scale test procedures, their strengths and weaknesses, and cases where AG/SAG pilot testing should still be performed.

Jan 1, 2012

By Pingyang Zhang, Caichu Xia, Shuwei Zhou, Yu Zhou, Yongsheng Hu

A lined rock cavern (LRC) is an alternative container for compressed air energy storage (CAES) to store high-pressure air that is later used to produce electricity. A critical requirement of CAES in LRCs is that the inner seal should provide adequate sealing capacity to prevent air leakage from LRCs. In many studies, rubber sheets are applied to build the inner seal. However, air leakage through rubber seals has not been given much attention and rubber seals are usually assumed to be absolutely airtight. Given that rubber is permeable especially under high air pressure, such as in CAES, air therefore leaks through rubber seals during CAES operations. In this study, a numerical analysis was conducted based on the permeation equation of polymers and the governing equations of thermodynamics of CAES caverns to analyze the characteristics of air leakage from CAES caverns through rubber seals. A planned CAES plant in China was considered as a case study. Results show that air leakage rate increases with increasing cavern temperature and pressure during air injection and decreases as cavern temperature and pressure decline during air withdrawal. However, in total, the daily air leakage percentage is in the order of magnitude of 10-3% in a typical operation cycle, which is much smaller than the critical value of 1%. Under a common range of realistic operations conditions, the daily air leakage percentage is still of the order of 10-3%. Therefore, rubber seals can be used to prevent air leakage in LRCs for CAES. However, the experience of Japanese pilot cavern indicates that the specifications for the on-site vulcanization jointing and installation methods of rubber seals still need improvement.

Jan 1, 2015

By W. J. Cherones

This paper describes the history of the development and application of the electric mining shovel in open-pit mining, dea1ing particularly with far-reaching advancements in three primary areas: metallurgy, mechanical design and electrical systems. Hoist drives and crowd drives, including the Magnetorque and Electrotorque systems, and the integral propel drive are given close attention.

Jan 1, 1972

By A. Michalkow

DELN ITE Mines Limited is located in Deloro township, on the west end of the south break of the Porcupine Camp. Mining operations are currently being carried out on the downward extension of a system of quartz veins in an andesite zone. This zone has been followed from surface to the present bottom level of 5,250 feet. The changing mineralogy of the vein system has involved an increase in tourmaline content from the surface downwards, so that the veins at the lower levels are composed of dark brown quartz-tourmaline. The drilling problem presented by these extremely hard veins was partially alleviated by the development and adoption of a one-inch drill bit. All blast-hole drilling is now done with the one-inch bit, without any difference in hole spacing.

Jan 1, 1962

By Limao Zhang

This paper presents a novel model to assess the risk of adjacent buildings in tunnelling environments based on Extended Cloud Model (ECM). ECM is an organic integration of Extension Theory (ET) and Cloud Model (CM), where ET is appropriately employed to flexibly expand the variable range from [0, 1] to (-8, +8), and CM is used to overcome the randomness and fuzziness during the gradation of evaluation factors. The risk level of a specific adjacent building is assessed by the correlation with the cloud models. A confidence indicator ? is proposed to illustrate the rationality and reliability of evaluating results. Ten buildings adjacent to Wuhan Metro Line Two (WMLT) are randomly chosen among hundreds of adjacent buildings for a case study. Results have proved to be consistent with the actual situation. Compared with other traditional evaluation methods, ECM has been verified to be a more competitive solution with high calculation accuracy, wide adaptability, as well as simplified computer programming. There are no stringent requirements on the quantity of training data during the modelling process, and the original data can be directly entered into ECM without a normalization procedure, avoiding the potential information loss. ECM can be offered as a decision support tool for the risk assessment in urban tunnelling construction and worth popularizing in other similar complicated projects.

Aug 1, 2013

By Binbin Luo, Northeastern University, Chuanyao Sun, Jie Liu, Yimin Zhu, Yanjun Li

"A series of new type collectors a-bromo-saturated fatty acids, CH3(CH2)5CHBrCOOH (a-BHA), CH3(CH2)7CHBrCOOH (a-BDA), CH3(CH2)9CHBrCOOH (a-BLA), CH3(CH2)11CHBrCOOH (a-BMA) were synthesized from saturated fatty acids and bromine by solvent-free method (Hell-Volhard-Zelinski reaction) in laboratory. The micro-flotation tests of quartz mineral were conducted at a relatively low temperature of 15 °C. The adsorption mechanism of such collectors on quartz mineral surface were established by zeta potential measurements, in conjunction with the results of quartz micro-flotation tests. The flotation results showed that the collecting ability is in the order of a-BMA > a-BLA > a-BDA > a-BHA for the flotation of quartz mineral, which also demonstrating that the a-bromo-saturated fatty acids (a-BFAs) are new selective collectors for reverse flotation to remove quartz mineral from iron ores at a relatively low temperature.INTRODUCTIONThe requirement of higher pulp temperature to maintain the activity of fatty acid anionic collectors which have been widely applied in technological process of iron ores reverse flotation lead to a great deal of energy consumption.The purpose of this paper is to synthesize a new modified collector with carbon chains from eight to fourteen atoms, with strong electronegativity bromine atom introduced into a-carbon position to improve the activity and solubility of the reagent so that it can be adopted at a comparatively low pulp temperature. The collecting performances of these new collectors on quartz surface were studied, and the structure - properties were discussed in light of zeta potential measurements and quantum chemistry calculations."

Jan 1, 2016

By H. Son

The three-dimensional (3D) reconstruction of as-built industrial plant models plays an important role in revamping planning, maintenance planning, and preparation for dismantling during the lifecycle of industrial plants. Recently, the 3D reconstruction of existing industrial plants was conducted using laserscan data to make surveying processes more efficient. However, the current 3D reconstruction process from laser-scan data is still limited due to the need for significant human assistance. Although a great deal of effort has been made to efficiently reconstruct 3D as-built industrial plant models, the presence of objects?such as equipment, pipelines, and valves of different sizes and shapes?in existing industrial plants significantly increases the complexity of laser-scan data and makes automating the reconstruction process more challenging in practice. The purpose of this study is to propose a knowledge-based approach for the 3D reconstruction of as-built industrial plant models from unstructured laser-scan data. First, pipelines were extracted from laser-scan data based on surface curvature information and knowledge about pipelines' sizes from existing piping and instrumentation diagrams (P&ID). Once entire pipelines were extracted, they were modeled based on skeleton features. Then, the remaining objects were clustered and grouped separately via the region grouping process. Afterward, clustered objects were retrieved and modeled based on global feature-based matching from the 3D database. Finally, the resulting model was checked to ensure that it was well-reconstructed according to the information regarding the relationships among objects abstracted from the existing P&ID. The preliminary results on actual industrial plants show that integrating knowledge into the reconstruction steps played an important role in the proposed approach and that this approach obtained accurate as-built industrial plant models from unstructured laser-scan data. The proposed approach could be successfully utilized to assist in many applications during the lifecycle of industrial plants.

Aug 1, 2013

By J. M. Belland

This paper deals with the geology of the Smallwood mine in relation to its influence on mining and milling operations. Structure within the orebody, and variations in ore grade and material types, will be described and associated with the various drilling, blasting and milling operations. The orientation of planes of weakness, either bedding or jointing planes, and contacts between extremes in material types influence the size of the broken material. Generally speaking, variations in grinding rates and recovery can be associated with stratigraphic sequence and metamorphism.

Jan 1, 1966

By T. B. Williams

Most geologists have felt the need of a longer base than is ordinarily available when using a Brunton compass or other convenient instrument for taking strikes and dips in the field. To overcome this difficulty a lath or stick with straight parallel sides is frequently used. This accessory adds to the accuracy of the work, but it is a decidedly inconvenient one for the geologist to carry, especially if he be heavily loaded or is travelling on horse-back or through thick brush on foot. The writer has abandoned its use in favour of a sturdy two-foot carpenter's rule. The rule preferred is manufactured by J. Rabone and Sons, Birmingham, England. It is provided with a good level-bubble set in one of the limbs, and a scale, of the protractor type, graduated to five degrees through 180 degrees, attached to the main joint at the middle of the rule. (See Figure 1). For an instrument of its kind it is very accurate, and, in addition to the uses mentioned below, it 'is a handy thing to have around any camp. It is frequently used when plotting roughly in the field and for a protractor when one is not available. When not in use it may readily be carried in the top of the high-boot or legging. Ordinary strikes are measured as illustrated in Figure 1, the compass being held against the rule, which is in a horizontal position. Dips may be measured in a corresponding way by holding the Brunton compass against the extended rule, which is thus used merely as a straight edge. It is usually much more convenient, however, to ? use the rule only for this purpose, in which case one foot of the length rests as a straight-edge against the rock surface. This adaption is shown in Figure 2.

Jan 1, 1929

By John F. Gartner

"Traditionally, the geologists of Canada have been occupied with the tasks of finding new mineral bodies, locating gas and oil fields or hunting for economic deposits of industrial minerals. A very minor percentage of graduate geologists have applied their skills to solution of the ""urban blight"" or employing their understanding of ""Nature"" for the optimum use of land by mankind. However, things are changing quickly. The role of the geologist in the planning process is being established. It is an exciting time! Geologists are now being consulted on a wide range of urban planning problems. These vary, tor example, from assessment of the geological environment for the new communities of Erin Mills and Meadowvale, which will have total populations in excess of 100,000 people (truly a satellite city), to a complete geological/ geohydrological assessment of the new sanitary landfill for the city of Guelph.Use of geologic techniques and methods for urban studies must be enhanced with certain skills not taught, in the past, to the geologist. These include airphoto interpretation, soil mechanics, geohydrology, municipal engineering and highway engineering to mention a few. The geologist has the unique training to assess the natural environment and to discover, warn and explain the implications of man's attempt to command his environment."

Jan 1, 1972

By Saravarim A.

"The aim in flotation systems is to control the grade and recovery of the product., numerical method or sampling and analysis is used to achieve this goal. Weakness of measuring instruments, lack of process knowledge, deficiencies in management and data processing in the control of flotation cells, has led the academic and industrial units to use numerical models. In this regard, using the results obtained from the experimental design carried out in the DTP line of Gol Gohar industrial and mining complex, a regression model was developed based on the analysis of variance. To present this model, after variance analysis of factors and interactions, all models were investigated and the final model was created based on 75% of the data. The model was tested with the remaining 25% of the data to confirm the goodness of the fit. The coefficient of determination for training and testing resulted 71% and 74%. Moreover, a feed forward back propagation neural network with different layers and neuron was used to model the results. The best network structure was 6-27-1 and the coefficient of determination for this network was 99% and 98% for training and test respectively. Given the complexity of neural network models and the relatively low accuracy of the regression model, neural network has a priority assuming we have access to a specialist. In addition, the results obtained from neural network can be used as expert systems to control and optimize the flotation cells.INTRODUCTIONThe primary objective of the flotation cell control is to maintain the product's (in this case tailing) recovery and grade, which represents the index for process efficiency and product quality. Continuous estimation of these indexes requires a significant amount of maintenance, and calibration of the continuous analyzers, in order to maintain an acceptable level of accuracy. Weakness of measurement equipment, lack of process knowledge and the general deficiency in management and processing of data in the flotation cell control, will lead industrial units to use smart methods such as mathematical models, regression and neural networks in near future (Panahi, Abdollahzadeh, & Sam, 2010). Artificial neural networks are inspired by the very complex structure of human brain in which millions of nerve cells solve problems or store information by communicating with each other. The duty of neural networks learning. It should be noted that learning in artificial neural networks is limited, and what is practically considered is the computing power of the network. A neural network consists of units called neurons, and has the capacity to handle a set of input data to produce a desired output data set. Each of these input and output data sets can be assumed as a vector (Soltanmohammadi & Noparast, 2006)."

Jan 1, 2016

By K. Mayhew, R. Bruce, A. Heidel, G. P. Demopoulos

"Teck and Aurubis are working together to commercialize a technology for the processing of copper arsenic sulphide concentrates that is economic and sustainable with regards to the environment and community. The pressure hydrometallurgical approach is a desirable option as mineral extraction and arsenic fixation can take place in a single autoclave vessel. A test work program was carried out where a range of copper concentrates with varying arsenic grades was processed under CESL leach conditions. This paper discusses the stability character (in terms of arsenic) of the resulting residues and their mineralogy. The basic ferric arsenate sulphate phase (BFAS; otherwise known as type 2) was identified as the main arsenic carrier. All CESL residues demonstrated high stability (<1 mg/L As) through a range of aggressive (pH and ORP) environmental leach conditions.INTRODUCTIONArsenic deportment and control in the copper industry needs an integrated approach involving each stage of the value chain, i.e. exploration, mine operation, refining process and mine closure. Teck Resources Limited (Teck), Canada’s largest diversified mining company and Aurubis, Europe’s largest copper producer, have formed a partnership to advance the application of CESL copper-gold technology for the development of high arsenic bearing copper resources (Bruce et al., 2011).Among the options for arsenic control in the metallurgical treatment of copper concentrates is the precipitation of ferric arsenate, which is widely accepted as the most suitable method for stabilizing arsenic (Ferron and Wang, 2003). The pressure hydrometallurgical approach to processing arsenic bearing copper concentrates is a favorable option as mineral extraction and arsenic fixation can take place in a single autoclave vessel. Under CESL pressure leaching conditions (150 °C, 1380 kPa) high copper extraction and arsenic (V) fixation is possible.Within the pressure leach autoclave, arsenate and ferric iron react to form scorodite type phases. The precipitate formed under CESL conditions is dependent on the Fe (III) /As (V) ratio and the tenor of cations and anions, particularly excess sulphate (Gomez et al., 2011a). Previous studies on CESL residues have found arsenic to be present as crystalline scorodite (FeAsO4.2H2O) (Bruce et al., 2011), basic ferric arsenate sulphate (BFAS: Fe(AsO4)1-x(SO4)x(OH)x·(1-x)H2O, where 0.3<x<0.7), and/or arsenate adsorbed on to hematite (Gomez et al. 2011b). Although not a focus of previous work, scorodite was the predominant precipitate formed when the concentrate Fe/As was <1.5 (Mayhew et al., 2010), and BFAS was the predominant precipitate when the concentrate Fe/As was >10 (Gomez et al. 2011b)."

Jan 1, 2012

By B. Surender Mohan

Mining lignite pollutes the environment and causes ecological damage if unattended. Being conscious of the importance of environmental resources for the well-being of the living system, the Neyveli Lignite Corporation (NLC) adopts the policy of environmental regeneration as the foundation on which productivity is built. NLC started investing on Eco Care and Environment Protection long ago and it continues. Early investment in environmental protection has resulted in steady growth of the Company along with a healthy environment. The future vision of NLC is to be in the vanguard among the contributors to the community, environment and the nation by developing and utilizing industrial and human resources to the optimum. Untiring efforts are being put in mines (NLC as a whole) to maintain and sustain the ecological balance arising due to continuous mining activity. NLC?s Environmental Management System is becoming a symbolic role model for many of the opencast mines in Southeast Asia. NLC has been bestowed with number of prestigious Environment and Sustainability awards in recognition of the mammoth contribution in maintaining a clean and green environment.

Aug 1, 2013

By J. A. Relf

The construction of refineries and gas conservation plants in the general Edmonton area in the early 1950's made available large quantities of by-product liquified petroleum gases (LPG). These gases, together with discovery of increasing reserves of natural gas in the Edmonton area, provided Canadian Chemical Company with two of the necessities for petrochemical production, namely, available and reasonably priced raw materials and fuel. This paper outlines the development of the $83 million Edmonton plant from its origin, together with a brief description of the processes and some of the interesting features involved. Several economic aspects of the petrochemical industry are high-lighted including its importance to the local community and the province. The paper reviews the relationship between the oil and gas industry and petrochemical manufacturing and indicates some of the factors that may affect the future growth of the petro-chemical industry in Wes tern Canada.

Jan 1, 1962

By Nav Dhadli

Tailings from Oil Sands MiningWhat are they? Challenges Solutions Regulatory Environment Definition of the AFD Tailings Treatment Process 2010 AFD Pilot/Demonstration ProgramTechnical challenges Performance and Results Next steps Oil Sands Industry Collaboration on Tailings Technology TAILINGS ?WHAT ARE THEY? Mixture of remaining water and solids following bitumen extraction process Composed of water, sand, silt, clay, small amounts of hydrocarbon (bitumen, solvent, and asphaltenes) A necessary part of production in excavation of oil sands and removal of bitumen

May 1, 2011

By O. G. Olvera, D. G. Dixon, E. Asselin, L. S. Quiroz

Dissolution rates of chalcopyrite (CuFeS2) were calculated using electrochemical impedance spectroscopy (EIS). The calculated dissolution rate decreased by a factor of 3.2 after the electrode was passivated. The results presented in this work indicate that the reduction of Fe3+ was the rate-controlling step for fresh CuFeS2 electrodes while the transport of cations within the passive film limited the dissolution rate for the passivated electrode. The transfer of cations at the electrode/electrolyte and passive film/electrolyte interfaces did not affect the dissolution rates of the fresh and passivated CuFeS2 electrodes, respectively. The catalytic effect of pyrite (FeS2) on the dissolution of CuFeS2 continued after the passivating treatment. The contact of fresh and passivated CuFeS2 electrodes with different FeS2 particles resulted in increased dissolution rates, due to an increase in the reduction rate of Fe3+.

Jan 1, 2014

By R. H. Beaton

"About 1905, a plant was constructed at C1ayburn, in the Lower Fraser valley, 4'5 miles east of Vancouver, to process shales from Sumas mountain into heavy clay products. In time, mining operations were found to be more favourable on the opposite side of the mountain, and by 1913 a plant, which soon became the centre of activities, was completed at Kilgard. Destroyed by fire in 1949, the plant was rebuilt on modern lines, and a second plant was established at Abbotsford, six miles to the west. The Company, from its beginning, has grown with development of the Province. In recent years, operations have kept abreast of latest developments, particularly in materials handling. Latest innovation has been the complete conversion of fuel from Bunker C oil to natural gas. In 1957 the Company became associated with Harbison Walker Refractories, Limited, a leader in its field in the United States, and its title was changed from Clayburn Company, Limited, to Clayburn-Harbison, Limited. Currently, the Kilgard plant produces sewer pipe, agricultural tile, and flue liner; the Abbotsford plant, refractories and facebrick. Improvement of products and development of new ones are tasks of a recently-completed testing and research laboratory.Almost all ware produced is marketed in Western Canada or Washing-ton State. The Vancouver area absorbs the bulk of structural clay products."

Jan 1, 1959