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The information age has definitely arrived and in fact has only begun to affect our business processes. Traditionally mining companies have been innovators and leaders with technology, but applying information technology systems to machines directly working on the mining extraction process poses challenges to those introducing the technology. Caterpillar is now presenting machine guidance and information systems for dozers, graders, blast hole drills, shovels, excavators, wheel loaders and trucks. These systems simply increase the flow of real information in real time and deliver it to the end users who can make informed decisions that effect real productivity gains and at the same time eliminate the role of the middle manager who used to monitor and control these activities. Technology also offers cultural changes that appear intangible, but offer significant gains to those that implement technology. Critics state that these intangible benefits are still available to traditional processes, however these intangible elements are never identified nor managed without the introduction of technology enhanced processes. The benefits of these technologies are real and dramatic, existing users offer impressive testimonials, but still the technology can be disproportionate in the time it takes to introduce to an operation. Caterpillar finds that senior to executive management needs to be a part of the technology introduction, to coordinate all departments and set technology strategies.  

Jan 1, 2000

By T van der Meer, A Salokannel, M Martikainen, L M. Nevatalo, J McCulloch

Water use and wastewater management is becoming a focus for many industries around Australia and the rest of the world. Good quality water is increasingly being recognised as a precious resource, and regulations on the bulk storage and discharge of waste streams is becoming more stringent in order to protect the environment, existing water reserves and the communities that use these resources. Components such as heavy metals, arsenic, cyanide, and sulfate from acid mine drainage are some that occur at mining and metallurgical processing sites. Removal of such components can allow safe re-use of these streams, reducing the new water requirements of the process, or else allowing acceptable discharge to the environment. Re-use or discharge of treated water eliminates or reduces the risk associated with storage of large volumes of contaminated water on site.Technologies where a contaminant is selectively precipitated and removed as a sludge are used for many of these treatments. Selection of the best treatment option for wastewater must depend on what is suitable to each site, and consider not only the nature of the contaminant, but also other aspects, including the location and situation of the site, local regulations, cost of reagents, the sensitivity of the local environment and waste sludge disposal options. To outline how an effective and economical solution can be designed and delivered, this paper will present a case study for the removal of arsenic from a site wastewater, from assessment of the problem, selection of suitable technology, design and implementation, to the benefits delivered to the site.CITATION:Salokannel, A, Nevatalo, L M, Martikainen, M, van der Meer, T and McCulloch, J, 2013. Technology selection for removal of contaminants from an industrial wastewater, in Proceedings MetPlant 2013 , pp 531-538 (The Australasian Institute of Mining and Metallurgy: Melbourne).

Jul 15, 2013

By Gieskieng, D. H.

Published tables of jaw crusher capacities are compiled for the most part from field performance data, interspersed with interpolations, extrapolations, various safety factors, and other modifications. Such a table attempts to balance and equalize field data from widely different materials, with differences of crushability, efficiency of feeding, sizing of the feed, and so on. The tests described in this paper were undertaken with the objectives of checking previously reported capacities; of studying the effects of various factors upon the capacity, including jaw plate curvature; and, if possible, of deriving a general capacity equation. Such an equation has been derived from the data obtained in these tests. It is given together with factors for its use. While more accuracy than is usually required may be obtained by careful application of the equation, it is of simple form and provides a convenient reference plane upon which the potential capacity of various crushers may be compared, and with which operating adjustments may be made on existing installations. The principal deviation in these tests from the usual approach consists of a laboratory technique which has been developed for the production of selected

Jan 1, 1949

By M. J. Hart

Today, aggregate producers in the Denver Metropolitan area, herein defined as Denver and surrounding communities in Adams, Arapahoe, Boulder, Douglas and Jefferson Counties, are scrambling to secure their future reserves. The Denver market is somewhat unique among the larger metropolitan markets in that the source of needed aggregate for the future is very much undecided. 2. Present Aggregate Resources Presently, the annual consumption of aggregate resources in the Denver Metropolitan area amounts to approximately 16 million tons of sand, gravel and crushed stone of which the later accounts for about 20%. Based on population growth projections for the front range, by the year 2000 the annual rate of consumption for aggregate in the Denver Metro area could be in the 25+ million ton range.

Jan 1, 1987

By C. M. Clapperton, K. E. Darke, A. J. Boyce, C. M. Rice, S. D. Redwood

"Abstract - The Kori Kollo gold deposit is hosted by a c.15 Ma sericitized dacite stock in the La Joya district on the Bolivian Altiplano. The mineralization is of the Bolivian polymetallic vein (BPV) type, with a significant amount of the gold reserves contained in the oxide cap. Field and microscopic studies, K-Ar dating, ??34S values of pyrite, alunite and jarosite, and ??18O values of alunite and jarosite demonstrate that some of this gold is supergene. Two types of supergene gold are present: minute gold grains, 1 to 10 microns across, of high fineness and associated with jarosite and iron oxy-hydroxides; and ‘invisible’ gold, which is probably sorbed onto minerals such as jarosite and iron oxy-hydroxides.Pyrite ??34S values fall in the limited range -3.5 ± 0.6‰, consistent with a magmatic origin. Sulfate ??34S values are homogeneous and overlap closely with those of pyrite (-1.2 ± 2.1‰), which supports petrographic evidence that sulfates replaced pyrite. By contrast, sulfate ??18O values are inhomogeneous with a large range (alunite +2 to 26‰, jarosite -5 to +18‰). These data are interpreted as reflecting kinetically controlled reactions involving various proportions of atmospheric oxygen and local meteoric water. This is typical of supergene alteration and is due to the seasonally dry climate of the Altiplano.The oxide-zone mineralogy is dominated by sulfates and iron oxy-hydroxide minerals with some phosphates and halides, which indicates that the groundwaters were acidic, oxidizing and relatively saline. Under these conditions the most likely complexes responsible for gold mobilization are halides.Geological data and K-Ar ages indicate that oxidation of the BPV deposits began at least around 11 Ma and possibly up to 15 Ma ago, and that supergene alteration lasted until around 4 Ma. During this period, erosion was minimal. Although supergene processes have been active on the Bolivian Altiplano since the Middle Miocene, in contrast to Northern Chile, enrichment of gold has not occurred."

Jan 1, 1997

By C. M. Clapperton, K. E. Darke, A. J. Boyce, C. M. Rice, S. D. Redwood

"The Kori Kollo gold deposit is hosted by a c.15 Ma sericitized dacite stock in the LaJoya district on the Bolivian Altiplano. The mineralization is of the Bolivian polymetallic vein(BPV) type, with a signi?cant amount of the gold reserves contained in the oxide cap.Field and microscopic studies, K-Ar dating, ??34S values of pyrite, alunite and jarosite, and ??18O values of alunite and jarosite demonstrate that some of this gold is supergene. Two types of supergene gold are present: minute gold grains, 1 to 10 microns across, of high fineness and associated with jarosite and iron oxy-hydroxides; and ‘invisible’ gold, which is probably sorbed onto minerals such as jarosite and iron oxy-hydroxides.Pyrite ??34S values fall in the limited range -3.5 ± 0.6‰, consistent with a magmatic origin. Sulfate ??34S values are homogeneous and overlap closely with those of pyrite (-1.2 ± 2.1‰), which supports petrographic evidence that sulfates replaced pyrite. By contrast, sulfate ??18O values are inhomogeneous with a large range (alunite +2 to 26‰, jarosite -5 to +18‰). These data are interpreted as reflecting kinetically controlled reactions involving various proportions of atmospheric oxygen and local meteoric water. This is typical of supergene alteration and is due to the seasonally dry climate of the Altiplano.The oxide-zone mineralogy is dominated by sulfates and iron oxy-hydroxide minerals with some phosphates and halides, which indicates that the groundwaters were acidic, oxidizing and relatively saline. Under these conditions the most likely complexes responsible for gold mobilization are halides.Geological data and K-Ar ages indicate that oxidation of the BPV deposits began at least around 11 Ma and possibly up to 15 Ma ago, and that supergene alteration lasted until around 4 Ma. During this period, erosion was minimal. Although supergene processes have been active on the Bolivian Altiplano since the Middle Miocene, in contrast to Northern Chile, enrichment of gold has not occurred."

Jan 1, 1997

By J R. Taylor, J A. Muchan, S M. Pape, B S. Davis

Acid and metalliferous drainage (AMD) is routinely derived from waste rock, tailings, pit wall rock, underground mine voids, heap leach pads, ore stockpiles, concentrate stockpiles and even slag piles. In many jurisdictions, there is an assumption that tailings materials represent the highest AMD risk. This is likely due to their highly sulfidic and ultra-fine grained nature, and the fact that they occur in large tonnage, partially unsaturated deposits. These characteristics are not unreasonably associated with reactive and therefore highly polluting mine waste materials. Interestingly, however, the high sulfide content and highly reactive nature of tailings achieves the rapid consumption of oxygen in tailings pore spaces. This oxygen depletion can limit or halt sulfide oxidation throughout much of the tailings pile. Oxygen can only be resupplied to the tailings via atmospheric exchange at the air-tailings interface. The grain size of most tailings materials limits this resupply to a diffusion related process that only affects the uppermost 100–2000 mm. Hence sulfide oxidation in tailings can be inherently self-limiting. Unfortunately, the same cannot be concluded for waste rock materials.Using a unique site assessment strategy that focuses on quantifying acidity fluxes from various domains at a mine site, it has become increasingly evident that sulfidic waste rock produces the majority (typically 60–80 per cent) of the soluble acid and metalliferous pollution at most active and decommissioned sulfide-bearing mine sites. Whether sulfidic waste rock is disposed in engineered above ground facilities, backfilled into pits or even underground voids, it remains the primary source of pollutants for decades to centuries.Conventional end-dumping waste rock practices result in angle-of-repose pathways for air and water, and these internal fabrics exacerbate sulfide oxidation (ie pollution generation) and discharge from waste rock materials. The primary aim of many cover systems is to retard the access of air and water to these conduits. Recent thinking is that more emphasis needs to be directed at strategic waste rock pile construction practices, and less reliance placed on thin soil cover systems to prevent AMD.Waste rock pile construction approaches that minimise porosity and permeability but raise the retained moisture content and enhance water residence times have the potential to lower sulfide oxidation rates and thereby improve water quality outcomes. For example, innovative base-up, layered and compacted (BULC) waste rock piles have the potential to avoid or minimise the generation of AMD, supersede the need for treatment and facilitate successful closure and relinquishment across the mining sector (Figure 1).CITATION:Taylor, J R, Pape, S M, Davis, B S and Muchan, J A, 2016. Waste rock pile construction to lower closure and relinquishment costs, in Proceedings Life-of-Mine 2016 Conference, pp 97–99 (The Australasian Institute of Mining and Metallurgy: Melbourne).

Jun 28, 2016

By Irving Hartmann, Bernard Lewis, John Nagy, H. P. Greenwald, H. C. Howarth

"ORIGIN OF INVESTIGATIONThe Federal Mine Safety Code for Bituminous Coal and Lignite Mines of the United States, July 24J 1946, contains the following provisions with regard to rock dusting: Article VI. - Section 2. Rock dusting.(a) All mines, except those mines or those locations in a mine which are too wet or too high in incombustible content to propagate an explosion, shall be rock-dusted to within 80 feet of the faces of rooms and entries; however, if the mine or any part of it is wet but becomes dry, the mine or portion of the mine so affected shall be rock-dusted as ·soon as it becomes dry. (b) In mines partially rock-dusted or in mines that are required to start rock dusting, haulageways and parallel entries connected thereto by open crosscuts shall be rock-dusted. Back entries shall be rock-dusted for at least 1,000 feet outby the junction with the first active entry. Inby this junction, the rooms, entries, and crosscuts shall be rock-dusted by generalized rock dusting as provided for in section 2(a).(c) Where rock dust is applied, it shall be distributed upon the top, floor, and sides of all open places and maintained in such quantity that the incombustible content of the mine dust will not be less than 65 percent. In trackless entries and air courses, protection in lieu of generalized rock dusting may be had by using bags filled with rock dust, if they are placed at regular intervals and staggered as described in Bureau of Mines Report of Investigations 3411."

Feb 1, 1948

By N. B. Gray, A. E. Guerra, D. E. Morton

"The formation of splash in pyrometallurgical operations that involve the injection of gases into a liquid has been the subject of a number of studies over the last few decades. Given the complexity of the phenomena, there have been some advances in understanding the microscale formation of splash but the ability to accurately predict the amount and character of the splash formed is still in its infancy. First, the macroscale mechanisms for splash formation is very varied. Second, the timescales for splash formation are very small, usually less than 100 milliseconds, making experiments elucidating the formation of splash difficult and costly. Work at the GKW CRC has shown that the microscale mechanism of splash formation is primarily is due to the Kelvin-Helmholtz instability. Substantial progress has been made in understanding the behaviour of large bubbles in effecting splash formation and a simple model has been developed to estimate the behaviour of splash formed from a top submerged lance. Direct numerical computation of splash formation using the GKMAC codes developed at the Centre has been successful in simulating the impact of liquid drops onto a liquid bath.IntroductionInjection of gases into melts is used in the metallurgical industry to promote mixing to ensure acceptable heat and mass transfer rates, conveying solids for alloying, provide efficient contact for gas-melt reactions, and as a reactant. High gas injection rates bring about the formation of splash and slop. Extensive splash formation leads to loss of valuable product, creation of safety hazards, formation of accretion on refractory lining and exhaust ducts, and increased load on dust removal equipment. Many operators and researchers have claimed that splash formation is the limiting factor in many gas injected processes. The problems listed above lead to loss of production and increased maintenance, adding to the cost of processing base metals. Over the last five years, the GKW CRC has been studying the formation of splash from a number of sources. They include the impingment of drops on liquids[ l·2.31, slopping of bath liquidI4.51, breakup of gas bubbles at the liquid-gas interfacel61, shearing of liquids by gases[7·81, and impact of packets of fluids on solidsl81. Theoretically, the extreme deformation of fluid shape and the influence of surface tension makes the simulation of flow resulting from only a drop impacting on a liquid surface a very challenging computational fluid dynamics problem. Recently, we have been successful in simulating the formation of the Rayleigh jet resulting from a drop impact showing the effect of drop Froude number on the shape of the Rayleigh jet."

Jan 1, 1996

By A. C. Richardson, G. D. Coe, B. M. Bird

"The Hull mine of the De'Bardeleben Coal Corporation is located in the Warrior field, in Walker County, Ala., about 25 miles northwest of Birmingham. The Mary Lee bed at this point is coking coal and has been used in the manufacture of by-product coke, but at present it is sold exclusively as a domestic and locomotive fuel.The data in this paper, which is the third in a series on the washability of Alabama coals,5 have been obtained in connection with an exhaustive study of coal preparation in Alabama now being conducted by the U. S. Bureau of Mines and the University of Alabama with the cooperation of the different coal operators. The paper contains screen-sizing and float-and.-sink tests of a representative sample of run-of-mine coal, and flakiness tests and crushing tests of certain sizes.In addition, complete analyses of the ¾-inch to 3/16-inch size, raw coal, together with ash fusibility tests of the float-and-sink fractions have been made; those results are given in Tables 1 and 2. Since they indicate that the pr ration problem, like that at Lewisburg, Ala., is one of ash reduction, the further tests and the discussion have been restricted to that subject."

Apr 1, 1931

By D J. Bradshaw

It is well known that the chemical environment determines the success of the flotation process, however its characterization and control is difficult to achieve. This work evaluates the use of various measurements, including mineral potential measurements, in gaining an understanding of the influence of varying parameters such as the milling media and the reagent suite composition on the flotation performance of a platinum group metal (PGM) bearing ore. The results showed differences in the response of the various mineral electrodes to the different conditions, however the changes in flotation performance of the different minerals in the ore could not be wholly described by the electrochemical changes, demonstrating the limitations of these measurements.

Jan 1, 1999

By Michael Mann, Kenneth K. Eltschlager

The International Society of Explosives Engineers (ISEE) Standards Committee has recently updated both the Field Practice Guidelines for Blasting Seismographs and the Performance Specifications for Blasting Seismographs. The revisions are the result of public and industry input along with recommendations of the ISEE Blast Vibration and Seismograph Section. The committee is comprised of blasting seismograph manufacturers, users and general interest personnel. On an as needed basis, subject matter experts are enlisted to advise the committee. Three phases of activities are necessary for each revision cycle: request for comment on the existing standard, first draft revision of the standard based on public input, and final draft approval by the ISEE Board of Directors. The ISEE standards revision process will be explained and each standard will be discussed along with the significant revisions from the latest revision cycle.

Jan 1, 2018

By R. A. Pyper

Laboratory leaching experiments were conducted to ascertain the effectiveness of acidic solutions of thiourea, CS(NH2)2, for dissolving gold from finely disseminated gold ores. The ore tested was from the Chipmunk orebody of the Northumberland mining district in Nye County, Nevada, USA. Extractions of up to 90 percent were attained from the ore. Extraction was shown to be dependent on thiourea concentration, ferric sulfate oxidant concentration, acid concentration, and leaching time. Optimum conditions were an ambient temperature leach near pH 1.0 utilizing 100-200 kg/t thiourea and 50 kg/t ferric sulfate for 8 to 24 hours.

Jan 1, 1981

By Javier Enrique Basurco Cayllahua

In this work, a gram-positive bacteria was used as biosorbent to elucidate the aluminum load capacity under different conditions related to metallurgical and chemical plants. The sorption data followed the Langmuir, Freundlich, Dubinin-Radushkevich isotherms. In order to determine the best isotherm fit, three error analysis methods were used to assess the data: correlation coefficient (R2), residual root mean square error (RMSE) and Chi-square test. The error analysis established that the Dubinin-Radushkevich model fits better the aluminum biosorption data. The maximum sorption capacity was found to be 41.59 mg.g-1. The maximum removal of aluminum was 95% at pH around 5. The experimental kinetics data was evaluated considering two models (pseudo-second order and pseudo-first order). This study indicated that the R. opacus is an environmental friendly biosorbent.

Jan 1, 2009

Reliable predictions of the long-term water quality and water level fluctuations in a final void are vital if mine operators propose to decommission final voids in open cut mining operations. The catchments feeding final voids typically comprise a large proportion of coal placed or re-shaped spoil piles. Spoil piles from open cut coal mining operations have distinctive hydrological characteristics, which result in unique run-off behaviour. There is a need to understand the nature of spoil hydrology processes in order to predict the long-term hydrological behaviour and water quality responses of such systems. Preliminary estimates indicate that it may take 20 or more years for a void to flood. It is impractical for mine owners and operators to wait until long-term hydrological and water quality conditions have been established in a void, before reaching agreement with regulators about mine closure conditions. Reliable simulation of the long-term water quality and water level fluctuations in a void are therefore. The adoption of an agreed modelling approach and sharing of results from field data programs could result in the establishment of a database that could be used, with regulatory approval, for assigning parameter values, without the need for a specific data collection program for every individual void. Industry and regulators should agree on the model adopted for predicting post-closure behaviour of spoil/void systems. This will require reliable, robust methods for field data collection. This paper describes the field monitoring, data collection, model preparation and simulations undertaken over a three year period for Australian Coal Association Research Projects (ACARP) Project C7007. It presents the findings of that research, and provides comment on aspects of the project that were undertaken well and on aspects that could have been done better. Limited data is presented in this paper due to confidentiality arrangements with the relevant mine sites.

Jan 1, 2003

By G. A. Davidson, P. G. Williams

"New developments in centrifugal slurry pump technology are discussed in relation to their importance for improving pump operation and reliability.Experimental data obtained by measuring the velocity of liquid flows in a slurry pump casing using Laser Doppler Velocimetry are presented. This demonstrates the importance of selecting pumps with the proper hydraulic design to provide optimum efficiency, maximum part life and minimum operating cost.The paper also discusses the use of new wear resistant materials, such as ceramic/metal composites, which can significantly improve the life of parts exposed to abrasive media. The results of laboratory attrition tests are presented. IntroductionCentrifugal slurry pumps are of primary importance for the hydro transport of abrasive and corrosive media in the mineral processing industry. As for all process equipment, slurry pumps must be carefully selected and operated to provide optimal performance. To achieve this, it is necessary to select equipment which will provide efficient and reliable operation for the specific service conditions and incorporates the best materials available to obtain maximum parts life.Abrasive wear of liquid end components is the most important aspect that distinguishes the design and application of slurry pumps from other types of pumps. It is therefore necessary to have a fundamental understanding of the mechanical interaction between pump components and the media being handled, as this will impact significantly on hydraulic design, mechanical reliability and selection of wear resistant materials. Recent advances in computational approaches'» have greatly improved the prediction of wear rates in pump casings by facilitating the solution of complex equations which describe the wear mechanisms mathematically. In conjunction with this, new experimental techniques allow researchers to measure flow fields in pump casings using non-invasive devices such as Laser Doppler velocimeters."

Jan 1, 1992

By Andreas Siegmund

During the decade of the nineties the conventional method of primary lead smelting (sinter machine/blast furnace) was successfully challenged by the introduction of novel direct and continuous smelting processes. In combination with a significant shift in market structure, as well as more stringent government regulations these modem technological innovations like the QSL, Kivcet, and Isa/Ausmelt processes became more than major competitors. They have proven to be economically and environmentally viable. The intensification of the metallurgical reaction by applying oxygen enriched or pure oxygen bath or flash smelting principles resulted in cost savings and a higher flexibility with respect to raw materials and additives usage. By synchronizing individual auxiliary plant sections with the smelting process a virtually waste-free production and low-emission mode of operation with nearly optimum energy exploitation is achieved. The primary lead industry will gradually substitute the sinter -blast furnace operation with novel high-energy efficient technologies in the new millennium.

Jan 1, 2003

By T. E. Swigart

In connection with experimental work by the Bureau of Mines to determine effects of back pressure . on oil wells * , data were compiled on the engineering conditions in the oil field selected , in order to afford a more complete understanding of the wells tested , and to illustrate the extent to which underground conditions should be studied when making oil -field experiments of this nature . This report , containing the data mentioned, may be of interest to the oil industry , as it describes briefly the methods of operation employed in developing and exploiting shallow well territory .

Feb 1, 1923

By H. D. Kline

This publication describes methods and techniques of mining and crushing limestone at 3 of 11 small quarries operated by Anderson-Oxandale Rock Co. in northeast Kansas in 1959. It is one of a series of reports by the Bureau of Mines on methods and costs of mining in various mining districts in the United States. The three quarries selected for study -Bosse quarry, Pottawatomie County; Hansen quarry, Morris County; and Huston quarry, Dickinson County (fig. 1) -were in many respects similar to many others that had been developed solely to fill local and usually transitory demands for crushed limestone for use as concrete aggregate, roadstone, and soil conditioning. Factors governing the choice of quarry sites were quality of limestone, shallow overburden, and proximity to points of consumption of the crushed stone.

Jan 1, 1962

By Essie Esterhuizen, Michael M. Murphy, Chris Mark

"The response of the surrounding rock mass to the creation of mining excavations determines the ultimate load on a pillar support system. In conditions where the ground is relatively soft and weak, the full overburden weight can be transferred to the pillar system. However, in stiffer and stronger rocks, a greater portion of the overburden load is transferred to the unmined coal barriers or abutments, and the pillar stress is reduced. This paper makes use of numerical models to examine the interaction between typical pillar systems and the surrounding rock mass for weak and strong geological conditions at various spans and depths of cover. The concepts of structural failure and functional failure of pillars are used to assess pillar performance when pillars are deformed beyond their peak resistance. The results show that the span-to-depth ratio is an important factor in determining the pillar stress and the ultimate deformation of pillars. The ultimate pillar strain appears to be closely related to the functional success of pillar systems.INTRODUCTIONThe National Institute for Occupational Safety and Health (NIOSH) was requested by Congress to study the safety of retreat pillar mining following the Crandall Canyon Mine disaster that took place near Price, Utah in August, 2007. As a part of this study, an investigation was made to better understand how the rock mass responds to the creation of mining excavations and how the loads are distributed among the pillars and the surrounding abutments or barriers. The outcome of these investigations contributed to the development of a modified loading model for the ARMPS-2010 (Mark, 2010) method ofretreat mining pillar design.Structural and Functional Failure of PillarsPillar design is typically conducted by estimating the pillar strength and stress, and then sizing the pillars so that an adequate margin of safety exists between the expected strength and stress. The pillar strength can be defined as the maximum resistance of a pillar to axial compression (Brady and Brown, 1985). If a pillar is loaded beyond its peak strength, load shedding or yielding can occur, and the pillar is considered to have failed as a structure. Structural failure generally refers to a loss of loadcarrying capacity."

Jan 1, 2010