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By George B. Saunders

The mines in western Canada producing steam coal will find a better opportunity this year to market their product in Winnipeg - for two reasons: First, the new wage schedules, signed with local unions at each mine, have enabled them to reduce the selling price materially. Second, the duty on slack coal coming in from the United States has been raised to 50 cents, which is equal to the duty on run-of-mine coal. This has had the effect of raising the cost of mine-run to .the importer. Formerly, it was the practice to bring in slack coal under a duty of 14 cents and lump coal under a 53-cent duty and, by judicious mixing of the two, manufacture a mine-run coal at an average duty cost of about 22 cents. Fortunately, through efforts of the Alberta Government, and other friends of the Canadian coal trade, the Federal Government was persuaded to adjust the duty on slack coal as indicated. While it will be found that the Manitoba market, this season, is slightly more easy of access we have still a long way to go before we reach the desired goal. Geographically and economically the Manitoba market should belong to western Canada. However, it has been found a very profitable market for United States mines because large tonnages of coal can be shipped, practically at the convenience of the mines, via the Great Lakes, during seasons of slack business. They will therefore not relinquish this market without a struggle.

Jan 1, 1925

By E. Peters

Roasting processes are divided into several elementary mechanisms, any of which could be significant or pre-dominant in a particular roast. The elementary processes considered in-elude beat transfer, gas-solid inter-actions with accompanying mass transfer between the bed and furnace atmosphere, vapor phase transport processes in solid-solid interactions, and solid phase diffusion processes. Examples are chosen of processes in which one of these mechanisms pre-dominates and some recently obtained data is presented to support the existence and significance of these mechanisms. Proposals are also made for future research in these areas, and for utilizing the information in the improvement of roaster capacities’ OASTING of ores as a preparative treatment for smelting or leaching has been practiced for so long that its origin has been lost in antiquity, but little has been under-stood of its basic nature until fair-ly recent times. The nominal chemistry of roasting processes is now understood; that is, the initial chemical com-pounds present in the ores or con-

Jan 1, 1961

By T. G. Joseph, M. Bolster, M. Curley

"High tirerim loading on haul trucks operating on rough ground frequently manifests as mechanical separations and rim base cracking caused by cyclic fatigue. This paper provides an understanding of the impact of high loads on rim component life and tire footprint, bulge, and deformation behaviour; and develops a maintenance planning tool to predict strain implications of high g loading for a given rim location. Loading tests and analyses were conducted for a tirerim arrangement under increasing load and internal tire pressure. Graphical models were developed, allowing higher g load extrapolation predictions for specific rim components.KEYWORDS g load, Mining, Model, Prediction, Rim, Strain, Tire bulge, Tire footprint, Ultra-class vehicleRÉSUMÉ L’application d’un chargement élevé sur le système pneu/jante de camions de transport rou¬lant sur des terrains accidentés se manifeste fréquemment par des séparations mécaniques et une fissure à la base de la jante engendrée par une fatigue cyclique. Cet article nous permet de mieux comprendre l’incidence de l’application de charges élevées sur la durée de vie des composantes de la jante ainsi que sur l’empreinte, la hernie et le comportement de déformation des pneus. Il développe également un outil de planification de l’entretien visant à prévoir l’incidence des contraintes en cas d’application d’un chargement g élevé sur un endroit donné de la jante. Des essais et des analyses de la charge ont été effectués pour un agencement pneu/jante soumis à une charge et une pression interne du pneu croissantes. Des modèles graphiques ont été développés, ce qui a permis d’établir des prédictions sur la base d’une extrapolation du chargement g plus élevé appliqué à des composantes spécifiques de la jante.MOTS CLÉS charge g, contrainte, empreinte du pneu, exploitation minière, hernie du pneu, jante, modèle, prédiction, véhicule ultralourdINTRODUCTION The purpose of this paper is to report on a proposed and trialed tire performance test based on data obtained from controlled testing that is used to predict the impact of high g loading on hauler rims and tires with greater accuracy. For example, for many years oil sand mining operations have expressed qualitative beliefs that an impact load of the magnitude experienced by a rim and tire arrangement is not detrimental to a rim as a stiff component; however, mining equipment components are subjected to cyclic loading where failure can result from repeated load/unload activity, truncating the peak region of a stress–strain response and resulting in fatigue failure at a stress value that is less than the peak value. The outcome reported by oil sand haul truck maintenance groups indicates they have realized that most high g impacts—such as those experienced by hauler tires and rims operating on poor ground conditions—can result in failure due to cyclic loading, where higher loads require fewer cycles for failure. This high-level loading and the resulting strain transmitted to the rim is evident in the results of the laboratory testing presented in this paper."

Jan 1, 2019

By J. W. McCammon

CRANGES in construction ideas and the continually rising costs of labour and conventional building materials, particularly since World War II, have prompted widespread investigations into the development and adaptation of new materials to meet the new requirements and to help reduce costs. Lightweight aggregates have been prominent in these investigations. The lightweight aggregates most commonly used today are foamed slag, cinders, pumice, diatomite, exfoliated vermiculite, expanded perlite, and bloated clay or shah. Lightweight aggregates contribute to the building industry in several ways: ( 1) in large structures the reduction in deadweight effected by the use of lightweight materials reduces the amount of reinforcing and structural steel necessary to support the structure; ( 2) the decrease in weight of lightweight blocks makes handling easier and faster; (3) pre-fabricated floor and roof slabs and tilt-up walls of lightweight concrete have become feasible and popular; ( 4) lightweight aggregate concrete has good nailability and is easily channelled; (5) concrete and plaster made with lightweight aggregate have good heat and sound insulation properties.

Jan 1, 1957

By Earl Gebhardt

The planning and design of mining panels in the Potash Corporation of Saskatchewan Inc., Lanigan Division mine Block B involved a number of investigative techniques. The techniques utilized to gain insight into the viability of mining included 2-D and 3-D seismic surveys, longhole drilling, exploration wells, photolineament, magnetic and gravity surveys, and actual room excavation.

Feb 1, 1993

By J. B. Hinzer, J. D. Harvey

"Noranda's Lyon Lake property in the Sturgeon Lake area of Northwestern Ontario was staked by Mattagami Lake Mines Limited in May 1969 to cover airborne Input anomalies. Subsequent ground geophysical and diamond drilling programs resulted in the disco very of the Boundary Extension, Lake and Creek ore zones. As of December 31, 1978, ore reserves were estimated at 3,945,000 tons assaying 6.53 per cent Zn, 1.24 per cent Cu, 0.63 per cent Pb, 3.42 oz/ton Ag and 0.010 oz/ton Au.These deposits are hosted within the South Sturgeon Lake volcanic pile of Archean age, which consists of several cycles of basic intermediate and felsic volcanic materials overlain by a sedimentary iron formation and built upon a plutonic base (Franklin , ' 1975). The top 50 m of the second felsic cycle, according to mine terminolo gy, contains the mineralization within Quartzphenocryst- bearing felsic lapilli tuff and underlying thin discontinuous graphitic sediments and altered coarse pyroclastics. The basal andesitic member of the overlying cycle forms the hanging wall to the ore deposits.Although there is no alteration pipe below the deposits, the coarse footwall rocks are permeated by chlorite, garnet, carbonate, iron sulphide and magnetitie-bearing veins intensifying from west to east.Immediate host rocks are alkali depleted and MnO, FeO, Zn and Cu enriched compared to Goodwin's (1972) average Archean rhyolites. Bedded pyrite-pyrrhotite-chalcopyrite lenses with sphalerite-rich tops are underlain by weakly developed stringer mineralization.Traversing eastward from the Lake Zone to the Creek Zone and toward the Sturgeon Lake Mine deposit, more rapid facies changes, more pronounced chloritic and carbonate alteration, the presence ofgarnets, greater MnO, FeO, CaO and Ag abundances, and increasing Zn/Cu and MnO/FeO ratios are apparent."

Jan 1, 1981

By E. W. Garner

THE greatest problem confronting business managers in modern times is not production, but distribution. It would be easy to expand productive output, but it is difficult to find markets for all that is produced. The fundamental source of economic difficulty, in the view of many observers, is a lack of proper balance between productive capacity and consumptive capacity. The studies conducted by the Brookings Institution on the general subject, "The Distribution of Income in Relation to Economic Progress", have led to conclusions of far-reaching significance, which may be summarized briefly as follows: (1) We have never lived beyond our economic means or capacity. (2) We have not been suffering from general overproduction. (3) We have not as yet reached a stage in our economic evolution at which it is possible to provide adequate standards of living for everybody. ( 4) It would require less than a 25 per cent increase in purchasing power among the masses to absorb our full productive capacity. (5) Production-curtailment programmes-whatever their merit in meeting temporary maladjustments-can only lead to national impoverishment. (6) Our inability to find markets adequate to absorb the full output of our productive establishments is explained by the unequal distribution of income and consequent restricted flow of purchasing power through consumptive channels. (7) The slow rate of growth of consumptive demand serves to retard the rate at which new capital is constructed, and hence the rate of economic progress. (8) The primary need is a rapidly expanding total income, and a broader diffusion of this income among the masses of the people. (9) A broader diffusion of income can best be achieved by reducing prices as rapidly as increasing efficiency will permit. That is to say, the benefits of technological progress, mass production, and low unit costs must be promptly passed on to consumers in the form of lower prices-giving more for each dollar.

Jan 1, 1936

By Adam Jordens

Along with gravity separation and froth flotation, magnetic separation is one of the most common techniques for separating minerals. Minerals are separated by a magnetic force that is dependent on a combination of the applied magnetic field, the magnetic field gradient and the magnetic properties of the minerals themselves. Minerals may be classified as diamagnetic, paramagnetic or ferromagnetic based on the way they interact in a magnetic field. The magnetic susceptibility of a material may be determined by using a vibrating sample magnetometer to determine the magnetic moment of the material in an applied magnetic field and then converting this measured moment into the material?s magnetic susceptibility. In the case of rare earth minerals, magnetic separation is commonly used to remove ferromagnetic iron-bearing gangue minerals and to concentrate paramagnetic valuable minerals such as monazite and xenotime. These magnetic separation steps are frequently preceded by a gravity separation step as many iron oxides and rare earth minerals have specific gravities that are much larger than those of typical gangue minerals. By varying the magnetic field intensity it may be possible to use magnetic separation to selectively separate the paramagnetic and ferromagnetic minerals that report to the concentrate after gravity separation. Test work on a Canadian rare earth ore has shown that a gravity concentration step using a Knelson concentrator was able to selectively concentrate heavy magnetic minerals as evidenced by increased recoveries, relative to the Knelson tailings and fresh feed, after processing through a wet variable intensity magnetic separator. Mass pull to the Knelson concentrate was 4.5 % and the magnetic recovery of this concentrate, at 0.94 T, was approximately 40 % higher than the magnetic recovery from the Knelson tailings (70 % versus 30 %). The products of the wet high intensity magnetic separation were also analysed using a vibrating sample magnetometer to determine the magnetic susceptibilities of the various concentrate and tailings products.

Aug 1, 2013

By J. U. MacEwan

Introduction The equilibrium between copper, zinc, and chlorine may be considered as the simultaneous equilibrium of the two separate chemical reactions of formation of the stable chlorides of copper and zinc at the temperature of the reaction i.e., l440°K. (1,167°C., 2,133°?F.)§ [Zn(g) +Ciz(g) ZnCl2z(g). ... (1) ] [2Cu(l)+Cbi'g) Cu2Cl2(l 1 ....... (21 ] Subtracting, [Zn(g) +Cu2(Clz(l i ZnClz(g) +2Cu!l) ... . (3) ] If this reaction is carried out with a copper-zinc alloy at some constant temperature above the melting point of brass, and at a total pressure of one atmosphere, the equilibrium concentrations obtained will depend on the free energy decrease .of the reaction as written in (3) and on the activities of the various components in. the reaction mixture. If the equilibrium is examined from the point of view of the phase rule, it is a three-component system, and if it exists in two phases (liquid and gas) it will have three degrees of freedom. If the restrictions of constant temperature and pressure are imposed, the degrees of freedom are reduced to one. This means that, in a two-phase system under these conditions, each different alloy phase will be associated with a gas phase of constant composition.

Jan 1, 1951

By G. Kordosky

The experience of one plant regarding degradation of copper solvent extraction reagents in the presence of 20 to 30 g/1 nitrate in the leach solution was described at Cobre 2003. However, little information is available about the degradation of copper solvent extraction reagents where the nitrate concentration of leach solution is much lower. Analysis of plant organic samples taken from an operating copper SX plant over a long period of time shows that small amounts of nitrate in the leach liquor can be a significant contributor to reagent degradation provided certain other conditions are present. These conditions are discussed and cautionary suggestions on copper SX plant operations in the presence of even low levels of nitrate in the pregnant leach are made based on industry experience with copper solvent extraction plants and copper solvent extraction reagents.

Jan 1, 2007

By C. T. Dzgoev, S. S. Gudkov, IRGIREDMET JSC, S. G. Schtoick, A. V. Yepiforov, S. V. Balikov, I. I. Yevtuschevich

The pressure oxidation (POX) and pyrometallurgical process comprises POX of gold containing sulfide and polymetallic lead-zinc concentrates prior to reduction smelting of POX products to generate a lead-silver-gold alloy. Refined lead and gold-silver alloys are then obtained using conventional processes. Zinc and other base metals are recovered from the POX solution. In the course of POX, zinc dissolves in the solution and lead concentrates in a solid residue in the form of sulfate compounds. Sulfur forms the major iron sulfates and jarosites. In order to dissolve sulfur and arsenic from solid residues to the solution, the slurry hot curing was carried out at the temperature of 95°C within 2 hours. After filtration of the slurry, zinc was recovered from the solution. The resulting cake was washed with water and subjected to hot alkaline treatment. After alkaline treatment, the cakes were blended with fluxes and subjected to reduction smelting to generate lead concentrate containing precious metals. This concentrate was refined to obtain refined lead and gold-silver alloy. After iron and arsenic were removed from POX solutions using sodium carbonate, zinc was precipitated as carbonate. After thickening and filtration, zinc precipitate was roasted to generate saleable zinc oxide. Using this process, the recoveries of values to saleable products were 97% Au and 95% Ag to the alloy, respectively, 91% Pb to refined lead and 5% Pb to lead and antimony alloy and 94% Zn to zinc concentrate. The features of the technology is that it has high recovery indices of precious and base metals to saleable products and can be used to process various polymetallic ore and technogenic raw materials.

Jan 1, 2016

By G. W. R. Kuzyk

"Hydraulic drills, recently implemented at the Tantalum Mining Corporation of Canada, Limited, Bernie Lake Mine, are proving to be an economic alternative to pneumatic drilling systems. The paper describes the application of an electric-hydraulic drill jumbo to the mechanized room-and-pillar mine and its performance. The application of these drills resulted in improved environmental and working conditions.Drill rods and bits are a major cost centre in hard-rock mining applications. The paper also discusses the performance of one manufacturer's product used on the hydraulic drills.IntroductionThe Tantalum Mining Corporation of Canada, Limited (TANCO) started producing tantalum ore from its Bernie Lake pegmatite in 1969. The pegmatite, encased in amphibolite, is shallow seated and flat lying. It is defined by diamond drilling along 4,000 feet of strike and 1,500 feet down dip, ranging in thickness from 60 to 280 feet. Relatively well defined zones of mineralization occur within the pegmatite and form separate orebodies of tantalum, lithium and cesium."

Jan 1, 1981

By Tim Gitzel

Thank you for your introduction, and thank you to the CIM for inviting me to make a presentation to you today. This is my first opportunity to report to you on the status of the Canadian uranium industry and I am pleased to tell you that the industry is in good shape, and well positioned for the future. As you will no doubt be aware, Saskatchewan benefits from the world?s largest known highgrade deposits of uranium as well as from a high level of provincial, public and northern community support. It is within this unique combination of geology and community that our industry operates. Uranium markets have been extremely competitive for a number of years for several reasons. First, deregulation in the nuclear electric power industry has tended to encourage fuel buyers to use up their large inventories built up at a time when rapidly increasing demand was anticipated. Second, alternate sources from surplus commercial stocks, military materials and reprocessed fuel have presented a major additional source of uranium supply. Today, these secondary supplies are meeting about half of uranium reactor feed requirements. Canada (that is, Saskatchewan) is the world?s largest ?natural? uranium producer with about a third of the global production. Saskatchewan?s mines produced more than 30 million pounds of yellowcake in 2002. Despite low prices, steady demand for uranium will continue. In fact, an increase in world uranium production in 2002 helped feed a more than 3 per cent increase in reactor fuel demand. Low cost production is important for surviving low market prices, but investments are based on longer-term strategies rather than simply responding to market cycles. Cost is not the only issue. In these times of increasing regulatory and public scrutiny we must continue to earn the trust of our stakeholders by adopting the highest standards and staying on the leading edge of technical, social and environmental developments. Managing these issues is as important as traditional concerns of ore grade and cost of production. The last two decades of the 20th century saw the Province of Saskatchewan rise to prominence as the leader in uranium production from facilities, which were at the time deemed world class. These facilities are now either at - or nearing - the end of their production years. We are now bringing on new facilities that will position Saskatchewan to remain the world leader in uranium production for many years to come.

May 1, 2003

By Egon Berger

"In recent years the trend in underground metal mining has been toward ever increasing blasts (often in excess of 100 000 tonnes per blast). The Canadian mining industry has been in the forefront of these developments (VRM, LBHand cable bolting to stabilize the surrounding rock /avoid dilution).In order to move these large tonnages, efficient loading systems have to be developed. This paper shows the technical and economic implications of various loading scenarios based on a predefined (however typical) stoping layout by:1 . discontinuous loading using scoop trams;2. discontinuous loading using scoop trams in combination with low profile dump trucks;3. continuous loading (based on loading performance/operating costs of the AL-60) in combination with low profile dumptrucks.The cost advantages of production concentration (loading large tonnages from one drawpoint}, made possible by continuous loading as opposed to sea tiered mining (small tonnages), using discontinuous loading in tunnelling will be presented, based on actual results obtained in a decline development project using the A L-60 continuous loader. At as pacing oj150m between turning bays, it was found that continuous loading was out performing discontinuous loading in approximately80% of the overall decline development.Fuel consumption and total cycle times are compared, and a cost assessment is presented.INTRODUCTIONThe subject of this paper deals with the introduction of continuous loading in underground metal mining and single heading tunnelingContinous mining has been widely introduced both in underground and surface coal mining. Mechanized longwall mining, utilizing moveable shield supports in combination with double drum- shearers, has resulted in a tremendous increase of coal production per working face.This has led to very concentrated mining operations. In a typical German coal mine two mechanized longwalls nowadays would produce the same amount of coal as 12 to 15 longwalls in the 1950s. One longwall in a South African coal mine has recently set a world record with 120 000 tonnes of coal in a single month.In underground metal mines-often due to the irregular nature of the ore body and the mining methods used-mining is far less concent rated. Ore is often produced from a large number of stopes and production sections. Sometimes, a substantial amount of ore may be obtained from development in the orebody (40070 at a German base metal mine)."

Jan 1, 1989

By Earl Gebhardt

"The planning and design of mining panels in the Potash Corporation of Saskatchewan Inc., Lanigan Division mine Block B involved a number of investigative techniques. The techniques utilized to gain insight into the viability of mining included2-D and 3-D seismic surveys, longhole drilling, exploration wells, photo lineament, magnetic and gravity surveys, and actual room excavation.IntroductionPotash Corporation of Saskatchewan Inc. (PCS) owns and operates four potash mines in the province of Saskatchewan. The Lanigan Division mine is located 110 Ian east of Saskatoon, Saskatchewan, near the town of Lanigan.The Lanigan Mine commenced production in August 1968under the ownership or Alwinsal Potash of Canada Limited. The mine was purchased by PCS in 1977.Lanigan Division's productive capacity is 3.4 million tonnes of product per year. Ore is extracted from the "" B"" zone or Layer III or the Patience Lake member of the Prairie Evaporite, more than 1000m below surface . The Patience Lake member (approximately 20 m thick) consists of potash interbedded with salt. The average run-of-mine ore grade is 21070 K20 (Fig. I).The mine was initially developed using the room-and-pillar technique. Improvements in mining resulted in the use or extensible conveyors in long panel rooms."

Jan 1, 1993

By Mohan R. Srivastava

- OUTLINE - apologies and explanations - a quick bit of history - the wisdom of Wikipedia - ?Matheronian geostatistics continued to convert Bre-X?s bogus grades and Busang?s barren rock into a massive phantom gold resource?? - variogram analysis for Busang - would variogram analysis (or variance analysis) have revealed the fraud? - what went right, what went wrong

May 1, 2007

By Peter Chmara

The measurement of dust concentration in Ontario mines since 1926 has been accomplished by konimetry, based on South African experience and methods. The introduction of a voluntary program of semi-annual surveys of air conditions at all operations throughout Ontario mines created a need for an instrument that would assess konimeter spots rapidly and accurately. The development of the Electronic Scanner, it is felt, answers this need. A program whereby all konimeter spot samples taken at Ontario mines will be counted at the MAP AO field offices in North Bay is described.

Jan 1, 1969

By Robert B. Parsons

"The Department of Finance introduced draft amendments to the resource allowance regulations on July 23, 1992 that effectively nullify the decision in the Gulf Canada Limited case. Prior to the amendments it appeared that only ""directly"" related general and administrative, capital cost allowance and scientific research expenditures had to be deducted from resource profits. Now ancillary expenditures are required to be deducted. Consequently, the ability of taxpayers to claim the resource allowance is curtailed.IntroductionOn October 25, 1990 it was almost certain that taxable mines were going to get a break. The Federal Court-Trial Division had just decided in Gulf Canada Limited's favour to allow it to claim resource related tax benefits larger than what Revenue Canada evidently wished. Revenue Canada appealed first to the Federal Court of Appeal and then to the Supreme Court of Canada. On January 10, 1992 the Federal Court of Appeal agreed with the Federal Court decision and on July 2, 1992the Supreme Court declined to hear any further appeal. A mere three weeks later, on July 23, 1992, the Department of Finance issued draft ""clarifying"" measures to amend the calculation of the resource allowance. These measures effectively nullify the benefits that arose under the decisions of the Federal Court."

Jan 1, 1992

By J. Manchisi

This study has investigated the use of blast furnace slag as functional adsorbent for metal ions in acid mine drainage treatment. This opportunity has not yet been developed into a practical process partly because of limited understanding of rates and mechanisms of adsorption process and inconsistency in interpretations of adsorption data. The overall objectives were to determine the efficiency and mechanisms of sorption process of metal ions in a multiadsorbate system. We employed standard materials characterisation techniques to analyse composition, structure and surface morphology of the slag. Batch adsorption experiments were then conducted to study the mechanisms, kinetics and efficiency of metal sorption as a function of pH, phase ratio, mixing time, mass and particle sizes of slag. Both XRF and adsorption data suggested the slag to possess acid neutralising capacity. This slag is non-crystalline based on XRD pattern, has adequate porosity and pore volume comparable to similar commercial adsorbents but it has inferior pore structure, pore size distribution and BET surface area to be effective under wide applications. Metal sorption increased with decrease in slag particle diameter, decrease in initial metal concentration and increase in the mass of slag. Although slags have demonstrated to efficiently treat low concentrations of single and multiadsorbate effluents using fine particle sizes, they have limited capacity to treat multiadsorbate systems for some metal ions. This is probably due to low affinity, competitive adsorption or limitation in material?s adsorptive properties. Sorption mechanisms probably involve precipitation and ion exchange on the basis of alkaline pH and exchangeable slag surface ions. Sorption preference is proposed as Fe2+>Cu2+>>Cd2+>Co2+>Mn2+. Despite these limitations, deeper understanding of sorption behaviour of metal ions by slags for application in dilute and large volumes of effluents is necessary where precipitation and other standard techniques are either inefficient or uneconomic. Thus, this study has established that sorption capacity of slag to remove metal ions from acidic effluents is selective, limited to certain metal ions and for other ions only at low concentrations. Further adsorption studies in multiple solutes under various experimental conditions or those that can propose an economic slag activation process are needed that improves or widens adsorption window.

Aug 1, 2013

By M. D. Griffith

"Ventilation models are a vital tool to ensure ventilation designs can provide airflow to all work areas in a mine. Airway resistance and variations in natural ventilation pressures will affect simulated airflow and heat distribution through a mine. Validating ventilation model resistances and pressures to the exact underground conditions can be difficult and the variances can contribute to significantly different simulation results depending on the structure of the ventilation design. The study will use sensitivity analysis to explore examples of variability of simulated airflow due to small resistance, heat and natural ventilation changes and thereby help the user identify both trustworthy and potentially unreliable parts of a mine ventilation model. INTRODUCTION Mine ventilation network modeling is a vital tool for ventilation professionals and has become increasingly relied upon during the design and operation phase of mine ventilation systems. However, they provide only an approximation of reality, and caution must always be exercised when drawing conclusions or making decisions based on simulated data. Ventilation modelling should be performed by persons with a sound fundamental knowledge of ventilation and ideally should be validated with field data, but in large mines, or mines which are yet to be mined, accurate input of the simulation variables can be difficult, and errors and inaccuracies may be difficult or impossible to avoid. This study discusses and investigates the sensitivity of the mine ventilation simulation results to input errors. In addition, there are limitations to what steady-state airflow and heat simulations can model, regardless of the accuracy of the model inputs. In some situations, steady-state solvers cannot capture the dynamic changing behavior of a ventilation system. This study will also describe and apply techniques to analyze the natural variability of mine conditions on ventilation models. The consequences of poor accuracy in some parts of a mine model may impact on the health and safety criteria of ventilation designs. For example, if an airway is required to flow in a particular direction and quantity, then despite a ventilation model showing correctly designed conditions, small errors in input values may result in incorrect prediction of the direction or quantity of airflow. This may create unexpected buildup of heat or gases during operational activities, causing safety issues or operational delays. The ability to know which parts of a mine ventilation model have increased potential for poor simulation results will allow engineers to consider the ventilation design and make changes if required to better guarantee the required design flows."

Jan 1, 2019