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By D. W. Partridge, W. Lamb, A. E. Lamb, S. Bird

Due to the constant need to improve SAG mill performance and efficiency, extensive research into all aspects of SAG mill optimization has been performed. This paper will review the current evolution of SAG mill shell liner design and their performance at the Copperton Concentrator. The effect of these liner design changes will be discussed with respect to: • Liner configurations • Mill operating performance, i.e., throughput, power draw, mill control • Mill mechanical performance, i.e., liner wear profiles, liner life, liner breakage, liner hardness • Foundry manufacturing considerations • Economic evaluation of throughput versus liner life This paper will discuss the results of Kennecott Utah Copper’s (KUC) and ME International’s (MEI) test work, providing an insight into the past, present and potential future opportunities of SAG mill liner design.

Jan 1, 2002

By W. A. Gibson, A. D. Trujillo

The Santa Rita copper deposit first served as a source of native copper for Indian implements and weapons. In 1801 Santa Rita copper, trans- ported by mule train to Chihuahua, began to be used commercially for making coins. It was a small- scale operation made difficult by Indian raids, transportation costs and depletion of the higher grade ores. There was, moreover, no known method for economically extracting copper from the under- lying low grade sulfide ores. Originally, copper and copper oxide ores were mined by underground methods, but there was virtually no development of the deposit-which became United States territory after the Treaty of Guadalupe Hidalgo in 1848-for almost a hundred years. A number of small underground mines had been started during that time, but it was not until 1873 that all the principal claims were consolidated under one control.

Jan 1, 1966

As part of its research on advanced mining technology, the U.S. Bureau of Mines emphasizes studies on in situ leach mining. This research enables the Bureau to develop technical information that can allow mining companies to adopt in situ leach mining methods. Research results should help to remove the technical and economic barriers currently hindering the development of commercial in situ leach mining operations. This report contains papers summarizing results of Bureau research on various aspects of in situ leach mining. A featured topic is the cooperative field experiment of the Bureau and Santa Cruz Joint Venture in a copper deposit near Casa Grande, AZ. Discussions in-clude an overview of the entire project, cost modeling, environmental permitting, laboratory core-leaching experiments, petrographic studies, and an evaluation of the geologic structure in the region. In addition, papers describe hydrologic modeling and geophysical studies of solution flow during leaching. Preliminary geochemical modeling studies are also summarized. A final paper describes a nonionic chemical additive with potential for significantly reducing the high costs of drilling in in situ leach mining.

Jan 1, 1989

By R. J. Matetic, J. S. Peterson, P. G. Kovalchik

The National Institute for Occupational Safety and Health (NIOSH) has initiated a study of a roof bolter to reduce noise exposure to mine roof-bolter operators. An important segment of this research entails determining the affect of various drilling configurations on the performance (penetration rate) and sound power emissions when drilling into granite. Test conditions included using various combinations of rotational speeds and thrusts, using 2.54- and 3.49-mm- (1- and 1 3/8-in.-) diameter hexagonal and round drill steels, using vacuum and wet conditions and using drill media of differing compressive strengths. This paper details the affects of each of these variables on the performance and sound power level emission. When drilling into granite, it was found that wet drilling generated lower sound power levels and performed better than vacuum drilling.

By B W. Riddol1s

The 1983 Energy Plan calls for an increase in North Island coal production from both underground and opencast sources from the 1982/1983 production of 843 000 tpa to approximately 3.4 Mtpa within the ten year period to March 1993. This increased production is scheduled to come from the following sources: Huntly West No 1 underground mine reaching full production of 1.26 Mtpa. Huntly East underground mine increasing production to 750 000 tpa. The proposed new Huntly West No 2 mine producing 100 000 tpa in its first year of operation û 1992. The proposed Ohinewai opencast producing 920 000 tpa for supply to the steelmaking plant at Glenbrook, replacing Weavers opencast which will be worked out in 1990. Rotowaro opencast producing at 220 000 tpa (currently being achieved). Two additional sources of supply which are not scheduled to begin production for at least ten years, and both of which have been designated for coal fired thermal power generation, are the Maramarua and Mokau coalfields. It was originally envisaged that development of both coalfields would be a combination of underground and opencast mines. The form of development is yet to be confirmed by detailed feasibility studies. The location of the Maramarua, Ohinewai (Waikare Coalfield) and Mokau deposits is shown on Figure 1. Worley Consultants Limited, in conjunction with their partners Rheinbraun Consulting GmbH (Germany) and Longworth McKenzie Pty Limited (Australia) have been involved with investigations and mining assessments for the Maramarua, Mokau and Ohinewai prospects. The Maramarua and Mokau studies form part of the New Zealand Coal Resources Survey programme of updating information to the Pre-Feasibility Mining Assessment level before proceeding to detailed feasibility studies. The Ohinewai study was commissioned directly by Mines Division to investigate the feasibility of mining coal by 1989 before reserves at Weavers opencast are depleted. This paper describes typical studies which are now being commissioned by Mines Division to investigate large-scale mining development and the effect geotechnical-conditions may have on coal recovery. The magnitude of these projects is reflected in the proposed outputs û up to2 Mtpa from individual mines û and the introduction of new continuous mining systems for both underground and opencast mines on a scale which has not previously been contemplated.

Jan 1, 1984

Keywords: Pyrometallurgy, Pretoria University Substantial research in pyrometallurgy at the University of Pretoria started in 1980 with the appointment of Rian Dippenaar to the Iscor Chair, a position that he held until 1996, when Chris Pistorius became the leader of this pyrometallurgy group. This paper reviews the main research themes over the quarter-century from 1980 to 2005, as well as some of the industrial developments that have shaped the research approach. The main topics have been the use of electrochemical sensors for equilibrium measurements, ilmenite smelting, steel processing, and reduction.

Jan 1, 2006

By Tianjiao Luo

Some literatures discussed on how to recycle the various reagent, but the discussion on how to reuse the waste liquid directly is very little. How to reuse the waste liquid directly was researched in this paper. Firstly, the waste liquid should be filtrated to remove the impurity; then some quantity of H2O2 solution was dripped into the waste liquid to pretreat it; finally, CuSO4solution was added into the treated waste liquid and the pH was adjusted to about 12, then some HCHO solution was added into the waste liquid, in which the treated carbon fiber can be plated. The morphology and composition of coatings were investigated by means of Scanning Electron Microscopy (SEM) and Energy Dispersive X-ray Spectroscopy (EDS), the deposition rate was mensurated by the way of dissolution. The results indicated that, the plating effect was basically identical with new plating solution, and the solution is stable, and the plating rate is still about 0.8µm/h, and the copper coating is even and combines closely with carbon fiber. According to this way, the waste liquid can be reuse 5~7 times.

Jan 1, 2006

By G. S. Rice, H. O. Howarth, Greenwald. H. P.

"Electricity as a means of transmitting power was introduced in coal mines of the United States about 1891 for both haulage and coal cutting, only a few years after electrical haulage was first installed on street cars. At first, the hazards of electrical ignition ere not appreciated and the general use of open lights and black blasting powder made the possibility of electrical ignition of fire damp seem small by comparison.5 The possibility of igniting coal dust directly by electric sparks or arcs had not been considered.In the nine years prior to 1900, the progress of introducing electricity underground was slow, except that it was used for lighting shaft bottoms. Electricity had to contend with the more general use of compressed air for coal-cutting machines and, in mainline haulage, with the use of mule-teams and endless and tail-rope systems. During this period, great improvements were made in electrical apparatus, in surface installations as well as in mines. By 1900, therefore, the technique of applying electricity in mines had so far developed that it rapidly drove out the use of compressed air in coal mines because of the comparative ease of its installation and the marked economic advantages of its use over that of compressed air in practically all kinds of mining machines except percussion. rock drills.At this time, however, little thought was given to the hazard of indiscriminate use of electricity causing explosions and fires, and the possibility of electricity causing direct ignition of coal dust had not been considered. On December6, 1907, however, the Monongah, West Va. mine explosion occurred. This was the greatest mine disaster this country has over had, 361 men being killed. Although: there was much diversity of opinion, as to the origin of the explosion, many well-informed engineers concluded that the cause was ignition of coal dust do to wreckage of a runaway trip in a rope haulage entrance slope. This slope also served as a ventilating and it extended from the level of the coal bed to the surface. The runaway trip tore down electric cables and stirred up a cloud of dust when it was wrecked at the bottom of the slope. The dust was probably ignited by the electric arcing that occurred when the wires were knocked down. (Another but less probable source of ignition was the open flames of miners lamps.) From the foot of the slops the explosion appeared to have travelled into the mine, spreading as it went. If this ignition of coal dust was the origin of the explosion, it occurred on pure intake air entering directly from the surface."

Oct 1, 1930

By E. G. King

As low-temperature heat-capacity and entropy data were available for only one sesquisulfide (cerium sesquisulfide), it appeared desirable to augment the information for this class of compounds by measuring the sulfides of antimony and indium. In addition a pressing need existed for data on indium sulfide to supplement vaporization studies in progress in the Department of Mineral Technology, University of California. This Bureau of Mines paper reports low-temperature heat-capacity measurements and entropy evaluations at 298.15° R. of antimony sesquisulfide of stoiehiometric composition (Sb2S3) and of indium sesquisulfide which was somewhat deficient in sulfur (In2S2.93). The data for the latter substance were adjusted to correspond to the stoichiome tric composition (In2S3 ) . Indium sesquisulfide has a lower entropy at 298.15' K, than either antimony sesquisulfide or cerium sesquisulfide, in line with the higher atomic density of the indium compound.

Jan 1, 1962

By Steven Putt

Seismic While Drilling (SWD) is a newly developed technology in the mining industry. Improving upon Measurement While Drilling (MWD) systems, SWD measures mechanical properties of the rock at incremental depths down a blast hole at a much higher resolution. SWD is also immune to common failures and inconsistencies of MWD such as operator and drill specific variation. Seismic While Drilling records the velocity and elastic modulus of the rock with centimeter accuracy in real-time. These properties measured while drilling blastholes are then used as a proxy for density which can be used for: • High resolution geologic modeling • 3D ore control • Drill and blast optimization • Drill to mill tracking One of the distinct challenges with SWD systems is the sheer volume of information acquired. With thousands of measurements per blasthole, the data can be overwhelming for even an experienced engineer. To overcome this complex challenge, the latest cloud computing and analytics models have been simplifying and organizing the data. These newer technologies can amplify an engineer’s capability by delivering actionable insights into their drilling and blasting workflows. The paper presents new results from Datacloud during recent Seismic While Drilling trials in iron ore, metallurgical coal, and hard rock mines around the world. The measurements are compared with wireline geophysical logs, core data, drill cuttings, and conventional measurement while drilling (MWD) systems to validate the technology and show how the data can be used.

By W. P. Roux

Owing to decreasing high-grade ore reserves, there is a need for better understanding of the jigging process to improve the recovery efficiency of finer, lower grade material. The use of positron emission particle tracking (PEPT) was examined as a technique to study the motion of iron ore particles inside a laboratory batch jig. PEPT is a non-invasive method that can provide three-dimensional kinetic data on a particle in laboratory-scale processing units and has been successfully used to study mills, hydrocyclones, and flotation. Experiments were conducted to determine whether PEPT would be a viable technique to study iron ore jigging and what valuable information could be obtained. The results indicated that detailed information on the stratification rate of a particle could be obtained, with adequate resolution to track the particle?s movement through an individual jig pulse.

Jan 1, 2014

By Thomas Z. Jones

Deep mining within the Sewell Coal member of the New River Formation in southern West Virginia has exposed several small-scale thrust faults and related features. The faults were en- countered in Westmoreland Coal Company's Eccles No. 6 Mine located near Beckley, West Virginia (Figure 1). The purpose of this paper is to: 1) describe the nature of these faults and the effect they have on mining, 2) discuss the roof support methods used in the fault zones, 3) establish a mechanism for the origin of the faults. and 4) demonstrate how the mechanism was used to forecast fault trends across the mine property.

Jan 1, 1986

By Huilan Yang, Feng He

This paper intends to introduce the development of copper smelting and converting technologies in China in recent years, with a particular emphasis on the introduction of various continuous converting technologies, and moreover, it analyzes the advantages and disadvantages of those technologies, including their impact on the downstream anode refining from different points of view. INTRODUCTION At present, many converting technologies are used in copper pyro-metallurgical plants in China, including Peirce-Smith (PS) converter, flash converting furnace, multi-lance based top blowing, bottom blowing and so on. These technologies have spanned a wide range of time. PS converter technology has been applied in copper smelters for many years and most of the blister copper have been produced by this technology; flash converting technology has been developed since 1990s and been maturely applied in several plants up until now; top blowing and bottom blowing technologies have been revived in China in the past decade and boast good environmental protection performance, energy efficiency, throughput capacity and short process flow. All of the said technologies have reference operations in treating high-grade matte. As more and more attention is paid to environmental protection globally and copper smelters continuously seek for cost reduction, it is necessary to share those converting technologies, especially those new converting technologies derived in China, with copper smelting practitioners in the world. This paper aims to analyze the advantages and disadvantages of various technologies from a macroscopic view and discuss their actual application effects, current developments and future improvements. BRIEF INTRODUCTION OF VARIOUS CONVERTING TECHNOLOGIES IN CHINA China has seen a rapid development in copper smelting industry in the past 30 years and has become the largest gathering place of copper smelters in the world, most of which are operating with PS converting furnace technology, however, with the increasingly strict environmental requirements of the Chinese government in recent years, the low-level pollution issue and the disadvantage of large gas exhaust amount per unit of copper of converting furnaces are particularly prominent.

Jan 1, 2019

By Gordon R. Sima

This contract is concerned with the construction of a Time Resolved Audio Dosimeter System consisting of one readout unit and several dosimeter units. The Time Resolved Audio Dosimeter System was designed and developed by the Bureau of Mines with the purpose of this contract aimed at obtaining additional units for further field testing and evaluation. All construction was in accordance with the Bureau of Mines design and/or Bureau approved drawings produced during the course of this contract. This report contains a summary of the construction efforts, problems encountered, recommendations and all drawings produced under this contract.

Jan 1, 1977

The Pilbara Block is a nucleus of Archaean rocks which lies in the North West Land Division of Western Australia, and it constitutes a mineral province that has been divided into two areas-the West Pilbara Goldfield and the Pilbara Goldfield.In the West Pilbara Goldfield two contemporaneous environments are represented by laterally equivalent volcanic and sedimentary successions which together comprise the Roebourne Group. The two successions are lithologically similar to the classical Warrawoona (volcanic) and Mosquito Creek (sedimentary) successions of the Pilbara Goldfield; but in the West Pilbara Goldfield there is no sign of the erosional break which separates the Warrawoona Succession from the Mosquito Creek succession. The Roebourne Group and the igneous rocks which have intruded it belong to the Archaean Pilbara System.Evidence of preconsolidation movement and igneous intrusion into unconsolidated sediment suggests that tectonism and igneous activity, localized along lines of fracture in an unidentified basement, beganbefore lithification was complete. Movement was primarily vertical, and persisted into the Lower Proterozoic.Vulcanicity and chemical sedimentation, accompanied by a diminution of detr:tal sedimentation, is thought to have caused a relative enrichment in the metal content of the middle part of the Roebourne Group; and the metal may have been remobilized during diagenesis and metamorphism, and localized in zones of dislocation formed both before and after consolidation of the sediments.INTRODUCTIONThe name "Pilbara" has been widely applied in the area under discussion, and to avoid confusion the various uses are summarized below.1. The town of Pilbara, now abandoned, was a centre of mining between 1888 and about 1914. It lies some 90 miles FJSK of Roebourne (Fig. 1).2. The original Pilbara Goldfield was modified several...

Jan 1, 1965

By M. Karimi

Artificial neural networks (ANNs) have found their applications in the modelling of unit operations of mineral processing plants. In this research, laboratory-scale tests were conducted, using a three-inch diameter Mozley hydrocyclone. Main parameters included pressure drop at inlet, solid per cent, vortex and apex diameter were adjusted. The corrected cut size (d50c) and the flow rates of underflow and overflow were determined. Multi layers perceptron (MLP) feed forward network architectures were designed to predict the responses. The results showed a good correlation between experimental and network output, for corrected cut size and flow rates. Keywords: hydrocyclone, artificial neural network, corrected cut size, flow rates.

Jan 1, 2010

By Chris Bennett, Drupad Desai, Kirit Mevawala

INTRODUCTION The design/build (D/B) philosophy of contract delivery is neither new nor unusual when it comes to at-grade, elevated or high-rise structures. But when it comes to constructing underground facilities, there were no examples to be followed in early 90sin the continental United States or its territories. When DMJM+HARRIS was selected as general architectural and engineering consultant for the Tren Urbano (TU) project in Puerto Rico, one of the requirements of the Federal Transit Administration (FTA) for funding commitment was to use TU as a demonstration project utilizing design/build contract delivery method. Now fifteen years later, New York City Transit (NYCT) has instituted a similar requirement for their first Tunnel Boring Machine (TBM) contract for the Second Avenue Subway. As with most construction mega-projects, lots of things have happened and there were several lessons learned from the TU experience that are now being applied to Second Avenue. Both of these projects require building tunnels and underground transit facilities in heavily traveled corridors of an urban city, in the vicinity of active business and commercial enterprises. To enhance the challenge, there are noise and vibration sensitive and historic urban receptors either over or along both the transit corridors. Column free Tren Urbano station caverns over18 m (60 ft.) wide were built in soft ground conditions within 3.6 m (12 ft.) of the surface under an aging heavy utility corridor, while NYCT tunnels with station structures stretching the limits of rock caverns to 34.8 m (100 ft.), were planned in rocky geology with the presence of shear and fault zones and some mixed face conditions. BACKGROUND During the early period of design/build experimentation, the speed with which the contract procurement packages could be put together enabled the owners to take advantage of the major efforts underway to rebuild the infrastructure that was suffering from post-World War II neglect. Use of design/build for new starts was unheard of and most of the projects were smaller in nature in order to allow the methodology to be tested. Development of functional design packages with the understanding that the D/B

Jan 1, 2005

By J Wesseloo and Y Kim, Y Potvin, G Mungur, D Grant

At the previous MassMin conference held in Sudbury in 2012, the authors proposed a new framework going beyond dilution and equivalent linear overbreak sloughing (ELOS) for stope reconciliation in relation to the planned stope design. More specifically, the new process investigates performance outcomes including rock overbreak (OB) and fill overbreak (FOB), rock underbreak (UB) as well as geomechanical and operational aspects such as blasting, fragmentation and other production data.Based on the findings of the original 2012 study, a comprehensive data gathering program has been undertaken involving design and reconciliation data from 43 stopes mined between September 2012 and October 2014 at BHP Billiton’s Olympic Dam (OD) operation. The new database structure was based on four types of data:stope definition and performance datastope geometrygeotechnical parametersoperational parameters.The new database allows a more in-depth investigation of stope performance. It is now possible to quantify and analyse UB and OB performance from each wall individually as well as the crown. In this paper, the influence of several parameters on recent stope performance at OD is analysed. The underlying reasons for stope wall performance outcomes are discussed in this paper.CITATION:Potvin, Y, Grant, D, Mungur, G, Wesseloo, J and Kim, Y, 2016. Practical stope reconciliation in large-scale operations part 2, Olympic Dam, South Australia, in Proceedings Seventh International Conference and Exhibition on Mass Mining (MassMin 2016), pp 501–510 (The Australasian Institute of Mining and Metallurgy: Melbourne).

May 9, 2016

By John S. Ball

[A system of analysis for sulfur groups in petroleum distillates has been developed as one phase of the Bureau-of Mines investigation of the more economic utilization of the so-called "black oils" of Wyoming. This problem is being studied by the Bureau of Mines under a cooperative agreement with the University of Wyoming at the Bureau's Petroleum Experiment Station , Laramie, Wyo. Wyoming black oils have high sulfur and asphalt content and usually yield only small percentages of straight-run gasoline. A more detailed description of the properties of black oils has been given in a previous publication (3)3/. The preparation and properties of asphalts from those oils have been described (1, 2), and the effect of thermal cracking and the use of ordinary methods of treating wore discussed in one Bureau publication (4), Although these studies gave considerable insight into the properties and characteristics of black- oils; it was thought t that a more fundamental attack would assist-materially in, the problem of sulfur removal.]

Jan 1, 1941

By G R. Mould

The paper presents a general background to the subsidence research program being undertaken by the Department of Mineral Resources and Development in New South Wales. The results of the studies undertaken over the last ten years are summarised. The differences between these results and those obtained by the National Coal Board are discussed. The results of a study carried out on the effect of total extraction beneath a freeway in the southern coalfields are discussed in some detail. The procedures developed for the construction of a 500 mm diameter natural gas pipeline crossing a number of collieries in the northern coalfields are also outlined. The future direction of the Department's subsidence research program is discussed.

Jan 1, 1980