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By F. Vahdatikhaki

Simulation techniques have offered significant boosts toward a cost-and-time-optimized planning of construction projects by enabling project managers to effectively comprehend the behavior of projects. Using historic data from projects of like nature, simulation considers uncertainties involved in a project through accommodating the stochastic modeling parameters. However, the heavy reliance on the statistical data and not taking into account the context-specific features of the project cause the degradation in the realism and accuracy of the simulation models. Similarly, the extent to which a historic pattern could be retrofitted to new projects will decrease in line with the growing uniqueness of the projects and the novelty of construction methods. Furthermore, the existing real-time simulation frameworks are not capable of distinguishing the transient environmental changes, with minimal long-term impacts on the productivity, from the influential changes that will greatly impact an operation. In addition, existing simulation tools are devoid of location awareness, resulting in the inability to consider safety threats in their representation of the project. To address these issues, this research proposes a framework based on the integration of new tracking technologies used in Automated Machine Guidance (AMG) with simulation-driven 4D modeling methods. The proposed framework automates the adjustment of the simulation model based on the updated data from the site, and thus transforms simulation from a predictive tool used at the planning phase to a proactive monitoring platform usable throughout the planning and construction phases. A prototype is developed to test and demonstrate the effectiveness of the proposed approach.

Aug 1, 2013

By D. H. Stonehouse

Of the f ive Canadian cement producing regions- Atlantic, Quebec, Ontario, Prairie and Pacific-Ontario has the greatest capacity and normally produces the most cement. However, during the last 5 years the greatest activity within the industry in Canada has been in the Prairie and Pacific regions where major capacity increases have taken place. Most Canadian cement companies produce normal Portland, high-earlystrength Portland and sulphate resisting Portland cements. Some companies also manufacture moderate Portland cement, and low-heat-of-hydration Portland cement. Escalating energy costs highlight the need for technology research into more energy-efficient equipment for the energy-intensive cement industry. The industry is well integrated and plants are well situated to support construction in Canada. Expansion into the United States has become common during the past decade.

Jan 1, 1984

By H. B. Farnam

"THE IRON ORE Company of Canada has been using do-it-yourself type explosives for three years. During the last 12 months we have used over 10 million pounds of ammonium nitrate-fuel oil explosives and either purchased or formulated one million pounds of slurried explosives.W e have been moving approximately one million cubic yards of stripping and ore per month and we expect our production rate to in-crease. Eighty per cent of our strip-ping and ore is soft enough to be blasted successfully with ammonium nitrate-fuel oil mixtures. Twenty per cent of our material is extremely hard and requires an explosive having greater strength than an AN-fuel oil mixture.W e had been using canned am-monium nitrate base explosives and TNT pellets to give maximum bottom loading density to fracture hard rock. As AN -fuel oil became widely used, it was apparent that other types of explosives could be formulated to fit our blasting requirements. Dr. M. A. Cook of the University of Utah was consulted regarding new explosives and together we developed the blasting slurries.Figure 1 shows a general view of one of our hard rock pits. The foot wall is on the right-hand side and this material is called iron forma-Figure 1.-General view of hard rock pitstion by our Company but is called 'Taconite by the operators on the Mesabi Range. This material runs 35 to 45 per cent iron and many pieces are hard enough to scratch glass. The formation is tilted at an angle of 55 degrees as can be seen in Figure 3.The bedding planes of this rock are about 24 to 36 inches apart and if the material is not well broken or fragmented, large chunks or slabs must be handled by the shovels which reduces shovel capacity and efficiency and increases maintenance costs."

Jan 1, 1960

By A P. Powell

This paper deals with the power plant at Cassiar Asbestos Corporation Ltd., Cassiar, B.C. It discusses the units installed in the plant, the distribution of power and the costs involved. The efficiencies and economics of this power plant are considered to be somewhat better than average. Introduction C ASSIAR Asbestos Corporation's power plant had its inception in 1952 with a 15-by 15-ft. log cabin containing two International Harvester diesel generator sets of 50 kw. total generating capacity. Over the years, it has grown to its present size -an 80 by 82 ft. by 35-ft.-high rigid-frame Butler building housing eight 2,300-volt diesel generating sets, a 2,300-volt distributing switchboard, a 550-volt auxiliary panel, three air compressors, six heat exchangers and other related equipment. The units in the power plant, numbered according to their order of placement, are rated as shown in Table I. The total generating capacity of the plant is 3,673 kw. All of the generators are of the open vertical design except that on No. 7 engine,

Jan 1, 1965

By M. O. Makwarela, M. W. Erwee, K. Bisaka

"Energy efficiency in mining and minerals processing forms part of Mintek’s long-term research strategy which includes a specific programme designed at overcoming the challenges faced by the South African pyrometallurgy industry.The electric smelting industry is currently severely constrained by the global economic downturn as well as by the availability and increasing cost of electricity. Efficient utilisation of electricity through energy recovery systems and improved smelting process flowsheets can significantly contribute towards creating sustainable operations.Apart from efficient engineering design and solid process control, smelting of either cold or hot pre-reduced ores has been shown to decrease furnace electricity consumption by more than 40%. Various methods of solid-state reduction tests have been carried out at Mintek in order to select the most appropriate process option in the context of the South African industry. This paper summarises a subset of the results obtained, specifically on pre-reduction tests done on South African chromite and manganese ore pellets.In this set of tests, it was found that the use of an organic binder, together with B2O3 as flux, promotes manganese ore pre-reduction, but retards the pre-reduction of chromite. By pre-reducing the manganese ore feed, significant cost savings can be achieved in subsequent smelting processes and there is potential to minimise manganese losses as a result of fuming, due to possible lower operating temperatures."

Jan 1, 2016

By Alain Simard, André Gobeil, Sylvain Lacroix, Maurice Rive, Denis Racicot, Pierre Verpaelst

"The Abitibi volcano-plutonic belt forms the major portion of the Abitibi lithotectonic subprovince in the Superior Province. The Abitibi belt is composed essentially of"" (1) approximately 2.7 Ga old volcanic and sedimentary rocks; and (2) gabbro, tonalite, granodiorite and syenite intrusions occurring in well-defined prekinematic ( synvolcanic ), synkinematic and post-kinematic plutonic suites. Most of these rocks are metamorphosed to greenschist facies. Regional multi-phase deformation affects the volcano-sedimentary rocks. Deformation was initiated as these rocks were formed, and peaked at the end of the Keno ran orogeny with the emplacement of granitic batholiths.There are 145 former and current mines in the Quebec segment of the belt. To date, more than 420 Mt of ore have been extracted yielding 1,600 tonnesof Au, more than4,000 tonnesof Ag,4,400,000 tonnes of Cu and 5,300,000 tonnes of Zn. Mineral production is concentrated in geologic domains that approximately coincide with the boundaries of lithotectonic domains. We have compared the geology and mineral deposits of different domains to illustrate their distinct metallogenic signature. Certain domains are dominantly gold-producing (Cadillac-Malartic, Val-d'Or, Caopatina), others are base-metal producers (Matagami and Normetal), while others produce both gold and base metals ( Rouyn-Noranda, Chibougamau, Casa-Berardi-Joutel).Gold is extracted from quartz-rich vein deposits (for example, Val-d' Or), sulfide-rich veindeposits(Cadillac or Chibougamau) and from volcanogenic massive sulfide deposits ( Rouyn-Noranda). Base metals are generally mined from volcanogenic massive sulfide( RouynNoranda, Matagami, Normetal), although certain vein deposits yield base metals (Chibougamau) . Certain sectors are dominantly zincrich (Matagami, Normetal)."

Jan 1, 1990

By Alain Simard, Andre Gobeil, Sylvain Lacroix, Maurice Rive, Denis Racicot, Pierre Verpaelst

"The Abitibi volcano-plutonic belt forms the major portion of the Abitibi lithotectonic subprovince in the Superior Province. The Abitibi belt is composed essentially of"" (1) approximately 2.7 Ga old volcanic and sedimentary rocks; and (2) gabbro, tonalite, granodiorite and syenite intrusions occurring in well-defined prekinematic ( synvolcanic ), synkinematic and post-kinematic plutonic suites. Most of these rocks are metamorphosed to greenschist facies. Regional multi-phase deformation affects the volcano-sedimentary rocks. Deformation was initiated as these rocks were formed, and peaked at the end of the Keno ran orogeny with the emplacement of granitic batholiths.There are 145 former and current mines in the Quebec segment of the belt. To date, more than 420 Mt of ore have been extracted yielding 1,600 tonnesof Au, more than4,000 tonnesof Ag,4,400,000 tonnes of Cu and 5,300,000 tonnes of Zn. Mineral production is concentrated in geologic domains that approximately coincide with the boundaries of lithotectonic domains. We have compared the geology and mineral deposits of different domains to illustrate their distinct metallogenic signature. Certain domains are dominantly gold-producing (Cadillac-Malartic, Val-d'Or, Caopatina), others are base-metal producers (Matagami and Normetal), while others produce both gold and base metals ( Rouyn-Noranda, Chibougamau, Casa-Berardi-Joutel).Gold is extracted from quartz-rich vein deposits (for example, Val-d' Or), sulfide-rich veindeposits(Cadillac or Chibougamau) and from volcanogenic massive sulfide deposits ( Rouyn-Noranda). Base metals are generally mined from volcanogenic massive sulfide( RouynNoranda, Matagami, Normetal), although certain vein deposits yield base metals (Chibougamau) . Certain sectors are dominantly zincrich (Matagami, Normetal)."

Jan 1, 1989

By P. R. Cook

Thunder Bay Terminals' plant, now in operation, cost about 70 million dollars and was completed on time and under budget. The paper is the project manager's account of this accomplishment. From site selection through feasibility, engineering and construction to realization, he emphasizes the necessary philosophies for the control of time and money. The computer as a tool is discussed, as well as techniques for procurement.

Jan 1, 1979

By Richard J. H. Barclay

The Lac Otelnuk iron property is located in the Province of Québec in the Northern Labrador Trough. The Labrador Trough is an extensive geosyncline of Proterozoic rocks, unconformably underlain by Archean gneisses. The Lac Otelnuk iron property hosts two significant magnetite iron-formation taconite deposits that outcrop, are sub-horizontal and are known to extend for at least 25 kilometres along strike. The host sedimentary rock package that includes a cherty iron formation is weakly metamorphosed to greenschist facies.

May 1, 2007

"Mining with blast holes drilled upwards may be done to recover sill pillars, or for economic reasons when the distance between the levels is relatively large. If the rock is sufficiently competent to accommodate large stope size, the distance between sublevels could be increased to as much as drilling accuracy allows. The same drill drift can be used for the drilling of both down holes and up holes. In the case of down holes, the initial opening of the stope (drop raise) is not as much a problem as for the inverse drop raise for mining with up holes. This is because, with a drop raise, a lot of space is available at the toe for the blasted rock to expand. In addition, the raise can be blasted in many shots, thus allowing smaller blasts each time. Inverse drop raises are generally much more difficult to blast because of the limited space for muck flow, and must, therefore, be taken down in a single blast, requiring special considerations in order to ensure a success. A case study of a 29 m (95 ft) inverse drop raise successfully blasted in a single shot at Heath Steele Mines is described. The paper covers technical considerations such as drilling accuracy, hole deviation survey, delay extension and protection, initiation methods and initiation sequence. Finally, a novel method for creating the initial opening called ’slot drilling’ is presented. This method, inspired from LKAB in Sweden, consists of drilling a row of interconnected holes using a special guide mounted on a regular production drill hammer.With a case study of blasting an inverse drop raise of 29 m (95 ft) in one blast, this paper further discusses some technical issues that are critical for the development of inverse drop raises. A novel method for creating the initial opening with a slot of interconnected holes is also presented with the experience acquired at different mine sites across the Noranda group."

Jan 1, 2000

By M. Wittke

"In the course of the extension of the railway network in Israel, currently the two 4.6 km long tubes of the Gilon Tunnels on the line from Akko to Carmiel are being constructed. The tunnels run through the limestones of the Bina- and Yirka-formations, which locally are karstified. The maximum overburden amounts to 160 m.The limestones are mostly horizontally bedded and vertically jointed. Occasionally also inclined joints exist. The tunnels cross various fault zones, which mostly strike at an acute angle to the tunnel axis and are steeply inclined. The karstic cavities which were encountered during tunneling have partially been filled by clay. In the vicinity of the fault zones, the rock has often been strongly jointed and weathered respectively. The two single-track tubes have a cross section with vertical walls and an open invert. The tubes are connected by cross cuts with a spacing of approx. 250 m.During the tender phase, WBI has elaborated the tender design for a joint venture of a Chinese and an Israeli construction company. After the joint venture had been awarded the contract, the preliminary and the detailed design have been elaborated by WBI and the construction works have been guided. On the basis of the geological description, rock mechanical models have been elaborated, followed by stability analyses on the basis of the Finite Element method. The tunnels have been excavated according to the shotcrete method. The support in most areas only consisted of a very thin shotcrete lining and radial bolts in the area of the roof. Depending on the degree of jointing and weathering, locally advancing support by means of spiles has been applied.The internal lining of reinforced concrete has been constructed in parallel to the heading of the tubes. Mucking and delivery of materials was carried out through the cross cuts.The breakthrough was achieved in April 2014 and thus within schedule. The predicted distribution of the excavation and support classes along the tunnel has been in good agreement with reality."

Jan 1, 2015

By Charles G. Kemsley

MR. C. R. WHITTEMORE: It is interesting to note that the mining industry is making increased use of alloy steels for drilling. They will undoubtedly lead to greater footage at lesser cost. Mr. Kemsley states that, for use in hard ground, the shanks are brought to a hardness of 435 to 440 Brinell by heating them to approximately l,800°F. It seems to me that this temperature is excessively high-it is considerably above the critical point of the steel. The only effect of such a high temperature is to lessen considerably the impact resistance of the steel. The possibilities of an oil quench, followed by a tempering draw which does not lessen the hardness of the steel too much but increases its toughness, might well repay further study; also the temperature control, a factor which depends on the composition of the steel. However, service results are undoubtedly the best criterion of practice. MR. KEMSLEY: I would like to point out that the steel is not quenched at 1,800°F. After heating to this temperature, it is laid aside to cool gradually; this high temperature is necessary to produce the required hardness by simple normalizing-cooling in still air. We all know that ideal conditions for hardening steel demand salt baths and furnaces with automatic temperature control, but for most companies the cost of such equipment having sufficient output capacity is prohibitive. The end we are trying to attain is to make good drills at a cost that will be within the means of any mine.

Jan 1, 1942

By P. M. Shibley

"IntroductionMine drainage, surface. drainage and process liquors are the principal mine and mill effluents. The quantity and quality of these flows varies according to mineralogy, type and scale of mining, the process, tailing disposal, local ground conditions and climate.Typical contaminants remaining after solids sedimentation are colloidal or semi-colloidal particles, acids, alkalis, metals in solution, cyanides and thiosalts. Environmental regulations and guidelines have been issued in detail by the appropriate government agencies and will not be reviewed here. Revisions and additions are being made as our comprehension and abilities increase. Some contaminants of consequence have not been specifically regulated as practical treatment technology has not been identified. Thiosalts fall into that category as do the derivatives of the first stage of cyanide oxidation - cyanates.Most mining activities have present or foreseeable water treatment requirements. Because process economics can be adversely skewed by the environmental factor, the acknowledged objective of every operation must be to identify and anticipate those requirements.The evaluation and selection of water treatment techniques for mine-mill applications is complicated by the fact that most mine-mill effluents are high volume, dilute and chemically complex systems. Treatment processes applicable to most contaminants are: chemical or biological oxidation; neutralization and/or precipitation; liquid/solids separation. Other processes such as ion exchange, electro-deposition, foam fractionation, freeze crystallization and reverse osmosis offer the possibility of selective removal or concentration of contaminents. The latter tediniques, representing a slightly higher level of technology, are less suited to the large, low value flows usually encountered in the mine environment."

Jan 1, 1989

By C. A. Hardie, G. F. Leichtle, J. A. Finch, J. A. Watson

"The recycling of wastepaper has become an important and common process worldwide. Techniques similar to those used in the mineral processing industry are used to produce high quality recycled fibres for use in newsprint. The mineral processing group at McGill University, in conjunction with the Pulp and Paper industry (Mechanical and Chemi-mechanical Wood Pulp Network), has adapted one of these techniques, column flotation, for the purpose of deinking wastepaper. This article describes the typical process of recycling wastepaper from a mineral processing point of view. It also presents results from McGill University’s flotation column test work at a Québec wastepaper recycling facility. IntroductionThe recycling of wastepaper has become an important and common process worldwide, including Canada which is now the world’s largest importer of wastepaper (CPPA, 1996). Much of the current drive to increase the utilization rate of recovered paper is a reaction to the solid-waste disposal problem that faces many Canadian and United States municipalities. The real problem in the disposal of solid waste is not the absolute amount of garbage that must be disposed of each year, but this amount in relation to available disposal capacity.Environmental restrictions on the creation of new landfill sites and incinerators (the two main options for disposal of municipal solid waste) have tightened the demand/supply balance in the solid waste disposal market. This shrinking availability of waste disposal sites in the face of increasing population with greater disposal requirements defines the Developed World’s solid waste crisis. Not only are there fewer disposal sites available, but the costs of using them is skyrocketing. These factors have increased government regulations mandating recycled paper content in newsprint. Conservation and environmental issues make the current drive for wastepaper recycling a real issue and business opportunity."

Jan 1, 1999

By N. Samman, S. N. Lau

"A series of new, grease-based, solvent free open gear lubricants were developed to meet the demanding service requirements of mining equipment. The use of these products has resulted in better performance under conditions of temperature extremes and in terms of longer component lives. They have gained widespread acceptance within the mining communities for such applications as the lubrication of mining shovels, draglines and ball mills.These products are WHMIS non-controlled and are environmentally acceptable. The benefits and advantages of using this type of product to lubricate mining equipment as well as the field evaluation and experience will be discussed."

Jan 1, 2002

By G. Scott Zimmer

Mine planning at Cassiar consists of an annual cycle of projection, control, evaluation and revision following completion of annual diamond drilling during the summer months . The inherent difficulty in evaluating fibre grade and distribution, combined with a high-wall phase or push-back mining system, requires continuous modification to designs and schedules based on a cumulative evaluation of equipment performance and prediction versus production. To expedite the planning sequence, a mini-computer system has been introduced which allows emphasis to be placed on optimizing designs, exempting personnel from manual calculations and tabulations.

Jan 1, 1978

By J. Seo

We propose a dynamic biomechanical simulation method that uses motion capture to evaluate the risk of Work-related Musculoskeletal Disorders (WMSDs). Statistics show that WMSDs accounted for 33% of all non-fatal occupational injuries and illness in construction in 2009, and were a leading cause of temporary and permanent disability. Present methods rely largely on self-reports from workers, observational techniques, and direct measurements of motion and muscle activity to assess awkward postures, physical loads, repetitiveness, and the duration of exposure. While these methods have helped to prevent WMSDs in construction work, they may not be suitable for estimating the internal tissue loads associated with WMSDs. We propose a dynamic biomechanical simulation method to estimate internal forces and moments at each body joint of construction workers with motion capture data. Particularly, we explore the biomechanical loads by simulating active 3D musculoskeletal models based on measured postures and movements. To demonstrate the feasibility of this approach, we studied a ladder climbing task using a portable ladder under controlled laboratory conditions. Postures and motions were determined with a commercial motion capture system (e.g., VICON). The results were analyzed to investigate the feasibility of identifying risk factors based on biomechanical simulation. The results show that the proposed approach allows us to determine the biomechanical basis for WMSDs, and to identify postures and movements associated with excessive physical demands on each body joint. When combined with marker-less motion capture which is our ongoing work, the proposed approach has the potential to assess an individual?s motions and to provide personalized feedback for the purpose of reducing biomechanical loads and WMSD risk in real workplaces.

Aug 1, 2013

By D. J. Bowen

"Abstract -The Great Dyke extends for 540 km along strike, to unknown depth, and varies in width from 3 km to 11 km. Rb/Sr age determinations gives values of approximately 2470 Ma.The Dyke consists of a variety of mafic and ultramafic rocks, many altered to serpentinites. These include, from top to bottom, successions of gabbro/norites, pyroxenites, peridotites/harzburgites, and dunites/picrites.The layers dip in from either margin, steepest at the edges (20°) and flattening toward the central sections. Four separate complexes are present. From north to south these are termed the Musengezi, Hartley, Selukwe and Wedza Complexes, and are described as 'boat-shaped' or 'pig-troughed'. All are similar in petrological sequences. Physiographically, the Dyke is spectacular in the north, where as a mountain range it meets the Zambezi Escarpment. Elsewhere in the central parts there is little surface expression and wide open treeless vleis. Dyke rocks cut through granite and schist belt terrain and are termed 'The Magnesia Belt'.Vast mineral resources exist. These include chrome, asbestos, platinoids, nickel, copper and gold. Up to eleven chrome seams numbered from top to bottom occur in the lower ultramafic sequences. Seams are narrow at 10 cm to 30 cm but of high grade. The platinum occurs 10 m to 40 m below the norite/pyroxenite contact.A 60 m wide zone of Light Sulfide Mineralization (LSM) of Jess than 1% sulfides extends from the lower gabbronorites into the upper pyroxenites. In this LSM, four enriched zones carry up to 5% sulfides. The most widespread is termed the Main Sulfide Zone (MSZ), below which is No. 2, No. 3 and No. 4 Sulfide Zones. The MSZ carrying pyrite, pyrrhotite and chalcopyrite is a multi­ element ore with components of PGE (Pt-Pd-Rh), nickel, copper and cobalt, and gold and silver.Extensive exploration programs have been carried out and the intention is to begin large-scale mining. However, with Russia supplying metals to the western markets, South Africa's cutback on production, and an end to the Cold War, delays have arisen."

Jan 1, 1994

By Jr. Arcand

Canadian Economy ? Getting Results ???? A stronger Canadian economy ???? National debt cut ???? Taxes reduced, tax-free savings account, support for manufacturing sector ???? Assisting with infrastructure Aboriginal issues affect all Canadians ???? Aboriginal prosperity is in everyone?s interest ???? Conditions for Aboriginal success include: - Indian residential school settlement - resolving outstanding specific claims

May 1, 2008

By F. McCarthy, R. McDonald, G. Woodbridge, G. Brock, D. Robinson

"The Direct Nickel process is a hydrometallurgical technology being developed to treat nickel laterite ores by leaching at atmospheric pressure. The leaching process uses nitric acid in a relatively large excess, is thus non-selective, and much of the soluble iron goes into solution. The first stage of solution purification is iron hydrolysis and the Direct Nickel process utilises the colligative properties of the pregnant leach solution (PLS) to enable the removal nitric acid of varying concentrations via distillation. Once sufficient acid has been removed, the boiling point of the solution is increased allowing high temperatures (up to ~170°C) to be achieved under atmospheric pressure. The higher temperatures initiate the precipitation of the iron primarily as hematite and allow the removal of the acid generated by the hydrolysis reaction. The rejection of the iron is near complete with solution tenors typically falling from 65 g/L Fe, or more, to less than 50 mg/L Fe. The separation of clean nitric acid from the PLS at this stage allows for relatively simple acid recycling. A hematite product with iron content above 60% could also provide an extra revenue stream.INTRODUCTION The Direct Nickel (DNi) Process is a novel hydrometallurgical processing route designed to treat all types of nickel laterite ores in a single flow sheet using nitric acid under atmospheric conditions. A simplified flow sheet is shown in Figure 1.Between 2007 and 2012 the process was developed and refined at Direct Nickel’s laboratory within the CSIRO Minerals’ facilities in Perth, Australia, and in 2013 a series of pilot plant trials were run under continuous operating conditions. The process is designed to treat both limonite and saprolite in the same flow sheet, and after comminution, the blended ore is mixed with nitric acid and leached just below boiling point in agitated atmospheric leach tanks. The acid is added in excess, so typically for a blend of limonite and saprolite the acid addition can be in the order of 1.8-2.0 t acid/t dry ore. After a residence time of between 4-6 hours the majority of the soluble metals have leached into solution and the insoluble leach residue is separated from the pregnant leach solution (PLS) via counter-current decantation."

Jan 1, 2016