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By J. A. Organiscak

Enclosed cab filtration systems are typically used on mobile mining equipment to reduce miners? exposure to airborne dusts and diesel particulates generated during mining operations. Various filter configurations can be used within the heating, ventilation, and air conditioning (HVAC) systems of cabs to remove the airborne contaminants. The air cleaning performance of cab filtration systems is highly dependent on the efficiency of the air filters, the number of filters used, and their placement within the HVAC system. This paper shows how to mathematically model cab filtration systems and illustrates a methodology for developing other cab filtration system design models. Node diagrams of several filtration system circuits are illustrated with their mathematical models at steady state airflow and concentration conditions. Laboratory and field data are presented to demonstrate the validity and utility of modeling enclosed cab air cleaning performance. The paper concludes that incorporating multiple filters throughout the HVAC system improves the air cleaning performance and robustness of the cab filtration system design.

Feb 23, 2014

By D Cooke

In 2010, Kalgoorlie Consolidated Gold Mines (KCGM) was Australia’s largest gold producer, with total annual production of 788 000 ounces. Of the gold produced by KCGM in 2010, 95 per cent was extracted from the Fimiston open pit, also known as the Superpit. The Fimiston operation encompasses the historic Golden Mile, from which more than 55 million ounces of gold have been extracted from the world-class Fimiston lode style mineralisation.The operational performance of the KCGM Fimiston open pit was reviewed for the period between 2005 and 2010. Key performance metrics reviewed included mined tonnes and grade, cost per ounce of gold produced and the mine to mill reconciliation trends. The years 2007 and 2008 were characterised by a decline in performance against key performance metrics. The ore zones were diluted, with the excess tonnes mined resulting in lower grade and an increase in the cost per ounce. Poor reconciliation between ore mined, the ore reserve model and the grade control polygons was also observed.A series of improvement initiatives were implemented in late 2008. As a result of changes made to the grade control and mining practices, the site performance recovered. Unplanned dilution was reduced, which had a positive impact on mined grade. The lower tonnes combined with higher grade reduced the cost per ounce to below budgeted levels in 2009 and 2010, enhancing the profitability of the operation. The operational performance between 2005 and 2010 was compared to the turnover statistics for the KCGM geology department over the same period. Turnover accelerated between 2005 and 2007, peaking at an annualised rate of 43 per cent. With the onset of the Global Financial Crisis and the implementation of retention initiatives, turnover reduced significantly between 2008 and 2010. A strong consistent correlation was observed between the turnover trends in geology and the performance of the grade control function and resultant site metrics.The cost of turnover is known intuitively, however, rarely quantified. To evaluate the benefit of the improved performance, a detailed financial model was used to quantify the impact of the grade control function. In 2010, the headgrade exceeding budget by just four per cent contributed an additional A$24 M of value to KCGM. In contrast, if the 2008 performance had been replicated in 2010 (-9 per cent on headgrade), the result would have removed A$61 M in value from the business. The KCGM experience between 2005 and 2010 demonstrates the value of human capital in a mining operation and the importance of a high performing geology grade control team to the profitability of a mining operation.

Aug 22, 2011

By V. L. SKITSKY

Geophysical Abstracts are published by the Division of Geophysical Explo- ration of the U. S. Bureau of Mines as an aid to those engaged in geophysical research and exploration. Inasmuch as geophysicists in the field may have little opportunity to consult libraries, the policy of the Division is to provide abstracts suffi- ciently informative in themselves to keep readers abreast of literature and patents published in the United States and abroad. - DISTRIBUTION. Abstracts 1-86 were issued as Information Circulars by the Burca of Mines; Abstracts 87-111 appeared as Bulletins of the Geological Survey; Abstracts 112-127 have been published as Information Circulars by the Bureau of Mines; succeeding issues will be resumed by the Geological Survey.

Jun 1, 1947

By Norman R. Paterson

"Under certain conditions useful gravity information of a reconnaissance nature can be obtained with-out measuring elevations by spirit level surveys on the ground. Gravity surveys can become part of a practical exploration program where high cost and slow progress previously hindered their utility. The advantages of the new elevation procedures are realized mainly in remote areas, in areas where ground transportation is slow and difficult and on surveys where the station spacing is large in comparison with the distance of the average optimum level shot. To utilize the advantages, transportation by helicopter or light plane is usually necessary. Methods of obtaining elevation control without leveling include: barometric altimeter survey; photogram-metric -APR spot determinations; methods involving the measurement of gravity gradients. The accuracies of these methods have been tested and compared with the normal accuracy of level surveys. It is felt that each method has its place in reconnaissance gravity work, particularly in the open areas of Northern Canada."

Jan 1, 1960

By J de Witte

When used in suitable ground conditions, rock bolts can have advantages over other permanent tunnel lining solutions. Permanent rock bolts offer flexibility in tunnelling profile and rapid rock bolt installation can enable time and cost savings. There are also disadvantages when considering the suitability of rock bolts for permanent support installations. These generally concern achieving the specified durability requirement over the specified design life. By investigating alternate approaches to rock bolt installation, quality assurance (QA), monitoring and design life it may be possible to alleviate some of these concerns.The design and construction benefits that can be realised through the use of rock bolts are primarily related to reducing project program time. This time reduction could be realised if rock bolts are considered as a permanent solution, with the installation being completed as a part of the primary excavation cycle. Any reduction of the program could allow direct and indirect cost savings and in the case of a major project, allow the revenue stream to be realised earlier.Currently ambiguity exists where the treatment of rock bolts as permanent support components is inconsistent with that of (often identical) ground anchors, as utilised in stabilising cut and cover structures. The ground support design process, implementation and testing are generally similar, though the acceptance of rock bolts as long-term support elements is treated differently to ground anchors in technical specifications.This paper discusses some of the benefits available through the use of rock bolts. It offers different solutions to the concerns surrounding durability, including alternate approaches to installation, Quality Assurance practices and monitoring solutions. The selection of an alternate design life is also investigated as another means of alleviating concerns around long-term durability. The paper will also provide an indication of savings that could be expected through the use of rock bolts as part of a long-term support system.

Mar 8, 2011

By Ernest Bohnet

Each mining operation is unique in some aspect ownership; ore body location, size, geometry, grade, mineralogy, hydrology, or geotechnical parameters; or constraints such as environmental regulations. However, all mining operations are alike in one aspect; the prime objective of any mining project is to maximize the return on the investment. This is the golden rule, or in the language of mining, the investor?s law of conservation. A mineral resource, by definition, does not become a minable reserve unless the mineral or minerals can be extracted economically (and legally). The three preceding sections have covered the various types of surface mining options. The choice of the most economic method is dictated primarily by the type of de-posit to be mined, the mining rate, and the physical characteristics of the deposit.

Jan 1, 2008

By V. M. S. R. Murthy, Biswaraj Dash, Somnath Chattopadhyaya

Tunnel boring machine (TBM) has been in focus for the last few decades and is currently the most preferred excavation method for metro, hydro and irrigation tunnels. Tunnelling in hard and abrasive rock conditions, in particular, is adversely affected by a very low advance rate coupled with increased TBM disc cutter failures and cutterhead jamming, seeking an in-depth understanding of the design and operational processes of the boring components of the TBM. The cutterhead and disc cutter are the critical boring components of the machine, influencing the boring process significantly. These components directly interact with the rock and hugely influence the machine’s efficiency. This paper encapsulates a review of prior studies related to disc cutter design and the cutterhead design for hard rock TBM tunnelling. A design methodology for designing and selecting a disc cutter and a cutterhead is suggested. The design methodology has been applied for a hard rock tunnelling case, and suitable design specifications for the boring components were arrived at. The disc cutter and cutterhead specifications designed based on the suggested methodology closely match with that of deployed TBM specifications. It may be observed that except for the case of high-strength and high-abrasive rock (greyish quartzite), for the rest of the rocks, the suggested design can meet the desired advance rates.

Jan 31, 2024

By T. C. Campbell

This Bureau of Mines publication presents an analysis of information related to the transportation of bituminous coal by unit trains and slurry pipelines. Even for short hauls from mines to markets, transport costs frequently account for between one-third and one-half of the delivered price of coal. Minimizing these costs has become an even more critical objective for hauls from the western mines than for hauls from farther east. Factors related to minimizing costs and transporting the western coal receive special attention. Although no general rule of preference is likely to be developed that can be applied to all shipments, both rail and pipeline service will be needed on an increasing scale. The study should provide useful background information and analysis for government and industry in approaching investment decisions in the mining and transportation industries.

Jan 1, 1975

By Daniel Hodouin

Artificial neural networks (ANN) are of growing interest in a wide variety of applications. Pattern recognition, speech processing, financial analysis, signal processing and process control are at present the most successful ones. This paper is an attempt to illustrate the potentiality of ANN applied to mineral processing. An introduction to the technology of ANN is first proposed to describe the various components and to explain the various phases encountered in setting up a network. Then examples are given to illustrate the use of ANN dynamic modelling of mineral processing units or plants and in process control.

Jan 1, 1991

By Mackenzie Burnett

Quick-Fix Blowout Stoppings were evaluated in several underground mines as an alternative to conventional ventilation control bulkheads. Blowout stoppings offer considerable savings in bulkhead construction and repair costs if the 0.1 inch H20 of differential pressure required to inflate them is available. The Quick-Fix Blowout Stoppings were utilized successfully in uranium mines in the Southwestern United States where savings in bulkhead construction and repairs to blast damaged bulkheads are estimated to equal $9,500 over the projected 2 year average life of a blowout stopping. Two types of material were evaluated. Five methods of anchoring the stoppings to drift walls were evaluated. Three methods of anchor attachment to the stopping material were evaluated. Blast pressure measurements were made in conjunction with the evaluation of the blowout stoppings.

Jan 1, 1978

By N Steenkamp, L Furstenberg, W Cele, M Richter

Managing productivity and improving efficiency for a healthy return on capital employed have become key mining industry strategies under prevailing tough global market conditions. However, achieving this in a multisystem environment such as a mining operation can be daunting. The field of discrete event simulation offers some relief, giving engineering teams insight into multivariable systems and stochastic processes. It allows for integrated system thinking and domain expertise to be woven into project thinking fibre. Directed system optimisation and therefore improved efficiency becomes possible. Furthermore, capital discipline accrues from optimal upgrade investments. This paper illustrates the practical application of this approach by reviewing a typical case study for a direct shipping iron ore operation. Dynamic simulation was used to establish maximum processing plant capacity under varying material characteristics and identify capital-efficient upgrades for increasing production.The study started with descriptive statistical analysis of existing data. Discrete equipment and system capacities were defined, followed by static plant mass balance calculations to establish bottlenecks and overall static capacity. Equipment ‘uptime’ and ‘downtime’ analyses established system and overall plant availability and utilisation. From this information, a dynamic simulation model could then be developed and initially calibrated against actual plant performance to verify its robustness. Once confirmed to accurately represent existing plant dynamics, system capacity response to variable changes could be tested to ultimately determine maximum plant capacity. Additionally, plant optimisation was incorporated to arrive at optimal upgrade points. Maximum capacity and necessary upgrades were established as a function primarily of feed size distribution. Additionally, the interfacing effects of rehandling feed material to the final product grade and potentially to life-of-mine were established as important outcomes. The results of the study illustrate the value of using dynamic simulation models to realistically and cost-effectively increase throughput.CITATION:Cele, W, Furstenberg, L, Richter, M and Steenkamp, N, 2015. Capacity evaluation of iron ore processing facilities utilising dynamic simulations, in Proceedings Iron Ore 2015, pp 597–604 (The Australasian Institute of Mining and Metallurgy: Melbourne).

Jul 13, 2015

By C. F. McCarroll

[Laboratory research and, control in the u?odnction an; utilization of petroleum and its product s have eqLmde& greatly during the past decade, rind much of the routine control and experimental equipment noirr requires the con-stant daily use of liquid nercury. In spite of this greater use, very little consideration has becn given to the hazard that might be occasioned by the toxic vapors of mercury unavoicl.a~l.p spilled or otherwise exposed to the atmosphere during the normcl 2rgced1u.e of ln30r~tor;~r operations. A sfmple visual exami~stion gf' sone of the laborztories reveals the prescnce of a considerable quantity of mercury in the craclcs of floors, on work tebles, ad on and mo7md eql~ipmeilt st.ads. Usually this yercurj ie contaminated with oily and dirt BO th~t it remint; in R finely divided state and a srnarl amount presents a relativell- lag? surface for evaporation. Since mercury shows meas~rable vo!-atility st a tempero.turc as lor^ 2s 8.5O F., mercury vapor will bo present in the atnosphere of anjr laboratory wbr.e mercury is exposed. promiscuously]

Jan 1, 1939

By Clayton Williams, Dale M. Hata, Glenn M. Boyce

The Upper Llagas Creek Flood Protection Project in Northern California encompasses portions of the communities of Morgan Hill and Gilroy, and unincorporated areas of Santa Clara County. The project provides for flood protection improvements along Llagas Creek and two of its tributaries, West Little Llagas Creek and East Little Llagas Creek. Llagas Creek is one of the tributaries of the Pajaro River and drains a watershed of approximately 104 square miles. The river system has a history of flooding the watershed communities, and the project’s goal is to provide 100-year flood protection by creating a bypass infrastructure, including channels, cut-and-cover culverts, and a tunnel. The project has been divided into several phases. This paper describes Phase 2A, which consists of approximately 2,150 linear feet of lined horseshoe-shaped bypass tunnel measuring 14 feet wide by 12 feet high. The bypass tunnel was sequentially excavated using a combination of roadheader and controlled blasting through colluvium and weathered to fresh greenstone. The tunnel was mined near residences, requiring strict noise and vibration controls. Phase 2A also includes the construction of twin bypass concrete culverts, portal shoring, and dewatering systems. It features the use of a Design Review Board and partnering for project delivery. This case study discusses the bypass tunnel design, progress of tunnel construction, plans to complete the work, construction risks, and the software and procedural tools being used to manage the project, including ProjectWise construction management software.

Jun 13, 2023

By M Brockman, M Cowan, A Robeson

"Sunrise Dam Gold Mine (SDGM) is located 820 km from Perth, 220 km from Kalgoorlie—Boulder and 55 km south of Laverton in Western Australia. The SDGM main pit had successfully operated since 1997 and was due to be completed during 2012. An opportunity existed to extract the high-grade crown pillar – 600 kt @ 7 g/t for 135 koz by either open pit or underground methods.The crown pillar was the 60 m (vertically) thick remaining part of the high-grade Cosmo orebody between the top of the paste filled underground mine stopes and the planned base of the final open pit shell.There were two major difficulties being considered when choosing the underground or open pit options:a major wall failure in the upper section of the main pit wall directly above the crown pillar restricting access from the base of the open pit to the top of the crown pillarimpact of a high rainfall event while the crown pillar was being mined from either surface or underground resulting in flooding of the underground mine workings.This paper will discuss the following issues:the process to identify and evaluate the risks in both options using knowledge based modelling software; this technique allowed the evaluation of a complex set of assumptions to arrive at the preferred optionremediation of the Watu failurethe selection of the preferred option and the challenges encountered before, during and after the extraction of the crown pillarthe planning and geotechnical work to ensure the safe extraction of the crown pillarsuccessful outcomes transitioning from open pit operation to a solely underground operation.Citation:Robeson, A, Cowan, M and Brockman, M, 2016. A Case Study on the Assessment, Planning and Extraction of the Crown Pillar at Sunrise Dam Gold Mine, in Proceedings Ninth AusIMM Open Pit Operators' Conference 2016, pp 115–136 (The Australasian Institute of Mining and Metallurgy: Melbourne)."

Nov 15, 2016

By William Gleason

"Modern society demands much more from the mining industry than just the raw materials it produces. In addition to providing copper, gold, coal and other minerals that make society function, the industry must conduct its operations in a safe and environmentally sustainable manner. This includes the equipment used and the engines that power the machines.In the United States, Tier 4 diesel engine standards that were set by the U.S. Environmental Protection Agency (EPA) are the strictest emissions requirement for off-highway diesel engines. This requirement regulates the amount of particulate matter (PM) and nitrogen oxides (NOx) that can be emitted from an off-highway diesel engine. In Europe, the Euro V standards are driving technology advancement in the sector.The European Euro V standards are required for new equipment manufactured beginning in January 2019. U.S. Tier 4 standards for heavy-duty off-road engines came into effect with model-year 2014 vehicles and equipment. China 6 standards come into effect in July 2020. India’s Bharat Stage VI standards will take full effect in 2020, and the phase-in of BSVIcompliant clean fuels began in April 2018.Caterpillar, Cummins and MTU are three of the leading manufacturers of engines for the mining sector. Each company is working toward creating efficient engines that can function in the often harsh environments found at openpit and underground mines around the world. In short, society is placing demands that are challenging engine manufacturers to deliver a product that can do more work while consuming less fuel and emitting fewer emissions.Technologies range from selective catalytic reduction (SCR) and diesel particulate filters (DPFs) to other engine strategies and emissions control technologies, which deliver near-zero black carbon and nitrogen oxide emissions, and lower greenhouse gas emissions. Caterpillar’s investmentCaterpillar, the world’s largest producer of mining equipment and mining engines, has been at the forefront of the changing demands placed on the industry and has remained on the cutting edge of engine development over the years, thanks to its investments in the sector.“Caterpillar made the choice to fund major engine and machine development work — even during a deep trough in the mining industry — so that Cat machines would meet Tier 4/EU Stage 5 mandated compliance dates of Jan. 1, 2018 / Jan. 1, 2019, respectively. For Caterpillar, these efforts enabled our mining trucks to provide improved engine component life to help our customers’ total cost of ownership (TCO) and produce a neutral TCO compared to our Tier 2 products,” said Jeff Castleman, new product introduction manager, large mining trucks for Caterpillar."

Aug 1, 2019

By Herbert H. Einstein

The innate variability of natural materials and processes causes uncertainty in the models representing the natural phenomena and uncertainty in estimating the parameters that are used in these models. Reliability analyses, in contrast to the traditional factor of safety approach, are well suited to a rational incorporation of uncertainty in design and exploration decisions. Probabilistic kinetic and kinematic analyses were developed and combined to form reliability analysis methods. With one method the reliability, i.e.) the probability of failure, of an individual 2-plane wedge in a slope can be determined. The other method is aimed at slopes with a single slope parallel set of joints. In each case two approaches were developed, an encompassing one relying on computer codes and a simplified or summary approach relying on charts or pocket calculator computation. A major contribution of these approaches is the treatment of joint persistance. Instead of having to assume a certain persistence, it is now possible to use exploration data on joint geometry and to include the persistence effect rigorously.

Jan 1, 1979

By K Knorr

Desktop X-ray powder diffraction using a D2 PHASER equipped with fast linear detector was performed on several iron ore and mill scale samples. Data were analysed using cluster analysis and Rietveld quantitative phase analysis. The quantitative mineralogy of both materials could be established. Thus the input is provided for understanding the energy consumption and the CO2 emission during iron production. Furthermore, tabletop XRD allows to distinguish iron ore from mill scales and to quantify their mixtures.

Jul 11, 2011

By Ross. C. Barkley

A computer program has been written to simulate ground vibrations induced by multiple-hole surface blasts. The program is an inexpensive and relatively easy to use tool for predicting the principal blast vibration characteristics that determine damage and annoyance potential: peak particle velocity, frequency content and pulse duration. The program generates a complete ground motion history by superposing, at any surface position, the vibrations induced by each individual explosives charge. It requires specification of (hence allows accounting for) the blast geometry, initiation sequence (including random delays), position with respect to blast, pulse characteristics induced by each charge, and propagation laws. A methodology is outlined to determine the necessary variables either on the basis of site investigations (e.g. velocity, attenuation, pulse), or by backcalculation from measured blast vibration records. The latter procedure has been applied to blasts from two coal strip mines. Main difficulties are backcalculating individual pulses, propagation (especially dispersion) parameters and delays. A normal distribution of delays, based on published results, has been shown to influence the results and the response of a single degree of freedom structure significantly. Broadening of the wave types included and additional verifications with field results are required.

Jan 1, 1983

By Armine F. Banfield

The Purpose of the Paper It is fitting that the first paper of a session on the Financial Aspects of Mining should be on the basic data upon which any financial discussion of a mining project must be based. The history of a mining project starts with exploration in an area considered geologically favorable for mineralization and culminates in the discovery of a body of valuable mineral material commonly known as a mineral deposit. Subsequently more detailed exploration establishes the approximate size, shape, tonnage and average grade of the deposit by surface and/or underground drilling, -surface trenching and/or underground workings. Some preliminary metallurgical testing and other studies, as required, are made at this time. Development work is then carried out to provide representative samples for determining flowsheet and metallurgical balances, preparing the deposit for production and establishing more firmly the grade and mining characteristics of the deposit. A feasibility study is then made of the engineering aspects of the project including the estimation of operating coats, the capital required to place the deposit into production, profit and return on investment. A valuation of the deposit

Jan 1, 1972

By V. V. Morozov, Ganbaatar Zorigt, Delgerbat Lodoy, Y. P. Morozov

"At the processing plant Erdenet, a new facility for advanced ore diagnostics in-stream (at the conveyor), based on optical analyser of mineral composition, was tested. Such systems provide highly accurate in-stream measurements of ore properties. The system provided information on the ore mineralogical composition, the particle size distribution and the impregnation of minerals. A special flatbed facility for optical spectrum-based estimation of fine-crushed ore has been developed, being incorporated into the existing system of ore sampling and analysis. Application of the flatbed facility renders possible a high accuracy of determining ore mineralogical composition. High precision of the optical spectrum-based estimation is achieved using special devices, installed in the sampling and the sample analysis flow sheet, applied by the technical control department. Modern systems for optical spectrum-based estimation of ore grade provide a basis for effective automated control of ore benefication processes, based on the principle of advanced ore grade control. Process management task of grinding and flotation was to choose options that take into account the composition and grade of the ore coming. The calculation data array comprises consumption of reagents, ore processing, grind size etc. The systems implemented at the processing plant contributed to increasing copper and molybdenum recovery. INTRODUCTION In-stream ore grade analysis is a new trend in effective control of ore benefication processes. This is realised based on radiometric measurements in the X-ray and visible spectrum regions, in which mineral components of the initial ore (Sbárbaro and Villar, 2010) or the benefication products become apparent (Hyotyniemi and Ylinen, 1998; Haavisto and Hyötyniemi, 2010). An important advantage of such methods is in-stream measuring ore parameters, including mass fractions of individual minerals, which makes it possible to use the information obtained in the processes of automated control."

Jan 1, 2018