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The Department of Resource Industries regulates and oversees safety and environmental standards for the mining and related industries in Queensland, and provides scientific support through its effort in the geosciences.The geoscientific data base accumulated over more than 120 years is very large. Therefore, accessibility to and utilisation of the data base in the most effective manner is an issue to be addressed in terms of modern information technology. The Department has developed a strategy whose implementation is progressing rapidly.

Jan 1, 1990

By Mahoney M

For gas content analysis in recent years, it has been standard procedure to report results on a 'dry ash free' (daf) basis, under the assumption that gas only adsorbs onto coaly material. In order to test the relationship between ash and sas content, samples of various rock types were taken from two drillholes in the Newcastle Coalfield. The results of this study confirmed the correlation between gas content and ash, providing an accurate means of relating gas contents for all carbonaceous rock types.

Jan 1, 1995

By M. J. Sheriff, D. H. Smith, W. Macdonald

The paper outlines the basic procedure used in electrical system planning and design. Consideration is given to the use of applicable codes and standards, development and use of a system One Line Diagram, power availability, load requirements and power factor. Also discussed are the factors influencing the selection of power supply and distribution arrangement, voltage levels, system grounding, distribution and utilization equipment such as switchgear, transformers, motor control, cable systems, motors. Short circuit calculation methods and system protection are discussed.

Jan 1, 1978

By A Murphy, D Lauder, J Miranda

Minera Alumbrera Limited operates the Alumbrera concentrator, treating a nominal 80 000 tpd of porphyry gold/copper ore. It is located in Argentina, 1200 km north-west of Buenos Aires in Catamarca Province, at an elevation of 2550 m above sea level. Treatment facilities consist of crushing, SAG and primary ball mill grinding circuits, rougher flotation, ball mill regrinding, gravity recovery and cleaner flotation. It is one of only a small number of concentrators in the world, which uses Jameson Cells alone for cleaner circuit flotation. Plant design was started in June 1995, with commissioning commencing in July 1997. Following a successful ramping up to design tonnages and recoveries, a number of options were reviewed to improve gold and copper recoveries. This paper concentrates on a detailed size by size flotation recovery project, commenced in May 1999. Utilising optical microscopy, scanning electron microscopy and analysis of surface chemistry it has allowed losses by size fraction to be quantified and options for enhanced recoveries to be developed. Coupled with extensive circuit surveys it has also provided an insight into previously unknown properties of Jameson Cell operation. Among these are unique residence time and bubble formation reactions to reagent and pulp flow variations, which has permitted a number of novel changes to the operation to maximise capacity and recovery.

Jan 1, 2000

By M. A. Trevits, G. W. Luxbacher, L. D. Patts

"It is almost a given that post-disaster mine conditions will have compromised the mine ventilation system, resulting in a hazardous atmosphere in portions of the mine, and often complicated travel through debris fields and roof falls. Robotic technologies provide the opportunity to gather valuable information to assist decision making or lessen exposure to dangerous conditions. MSHA's Mine Emergency Operations Division (MEO) has utilized a fully permissible mine robot, the V2, for a number of years, constantly updating the unit as new technologies became available. The National Institute for Occupational Safety and Health, as part of the MINER Act Extramural Contract Program, examined the need for additional robotic units and ultimately funded three different types of prototype technologies: two robots, the Snake Robot and the Gemini-Scout, and a mine rescue robotic assist vehicle known as the ""Mule"". The Snake Robot is designed to be lowered through a borehole and to conduct surveillance (gas monitoring, video and audio) in the immediate vicinity, while the Gemini-Scout, designed to be deployed in the mine opening, serves as a more mobile and agile exploratory tool as compared to the MSHA V2 robot. The Mule was developed in response to needs expressed by mine rescue teams for a versatile remotely operated support vehicle and it will move from prototype to MEO utilization in the near future. This paper describes the development of the robot prototypes and discusses their limitations in the prototype stage, possible enhancements and potential applications, as well as the utilization of the Mule. INTRODUCTION The conditions in a coal mine may be dramatically altered after a mine fire or explosion. For example, the ventilation system may not be functioning correctly as control devices may be compromised or damaged beyond repair. The visibility in the mine opening may be limited due to accumulated smoke and dust. Roof support systems may be damaged or no longer functional. Equipment and materials may be strewn about the mine opening. Debris fields, blocked openings, roof falls, flooded areas, gas accumulations and active burning make it very difficult or impossible for those managing the post-event emergency to permit mine rescue teams to enter the mine to conduct search and rescue operations. With the evolution of robots and robotic assist technology there has been a proliferation of purpose-built units for the military, police and law enforcement agencies, urban search and rescue and those contending with hazardous environmental conditions. In each case, the technology used is designed to limit human exposure to the unsafe conditions or to provide access to areas under difficult conditions. For example, a specially-designed marine robot has been deployed into the damaged core of the Japan’s Fukushima Daiichi Nuclear Power Plant to assess the conditions of the containment vessels, where melted fuel is believed to have accumulated. Human access to the area is prohibited due to dangerously elevated levels of radioactivity [1]. Multiple robots were deployed in Amatrice, Italy, to assist in the response after the 6.2-magnitude earthquake devastated the town. The robots were used to explore two medieval churches that were severely damaged and deemed too dangerous for human entry [2]. Tactical robots are regularly used by police and law enforcement agencies when the conditions of the emergency place intervening officers directly in harm's way [3]."

Jan 1, 2018

By D. G. Lynch, M. R. Martin, R. J. Coutts

"Broadmeadow Mine is an underground longwall mine located in Central Queensland, Australia. The mine introduced a top coal caving (TCC) longwall face in 2013 but since then has experienced severe convergence events at the start of each panel after 60–70m of retreat, resulting in equipment damage and the longwall almost becoming iron bound. A significant geotechnical monitoring effort during LW10 and LW11 to characterise the caving mechanics and operational changes during LW11 were successful in mitigating the risk posed by these initial convergence events. This paper describes the geotechnical monitoring programme undertaken during LW11, the operational methods used to mitigate these initial convergence events, and the contribution to these events of the TCC technique.A thick sandstone unit close to the extraction roof was likely the cause of the convergence events at the start of each longwall panel. However, stress change monitoring cells, surface extensometers, an inclinometer, and the blockage of holes designed for pre-conditioning using hydraulic fracturing indicated that the convergence events were not caused by the sudden collapse of sandstone bridging across the goaf. Rather, they were caused by the propping action of strong units within the overburden strata. Equipment design modifications were made to allow the longwall to remain operational during the convergence events and an operational strategy was implemented to mitigate convergence in LW11. The initial convergence event was successfully negotiated, and Broadmeadow went on to be the highest producing longwall for CY16 in Australia.INTRODUCTIONBroadmeadow Mine is an underground longwall mine located in Central Queensland, Australia, owned and operated by BHP Mitsubishi Alliance (BMA). The mine is a punch longwall mine using open cut pit access provided by Goonyella/Riverside Mine. Broadmeadow commenced longwall operations in 2005 using a conventional high reach longwall, but later changed to the top coal caving (TCC) method of extraction. Broadmeadow extracts the easterly dipping 5.5–7.5m-thick Goonyella Middle Seam in ranging in depth from 90m to 330m. The coal is washed and blended at the adjacent Goonyella/Riverside open cut mine to produce a premium coking coal product for export."

Jan 1, 2018

By Ben E. Lindsly

The recovery or partial recovery of the oil remaining in oil sands after the usual methods of production have become unprofitable is perhaps the greatest problem in the petroleum industry today. The amount of this oil remaining in the sand is variously estimated by those familiar with the subject to be 25 to 90 per cent of the original content.2 Lewis3 states, "The estimate of 80 to 90 per cent of the oil left underground does not seem incredible."

Jan 1, 1926

By D R. Seaman, R P. Tooher, B A. Seaman

"Several mine scheduling tools exist for use in optimising and scheduling the reserve according to in situ value. These tools generally value the ore on a per block basis according to regressed recovery models based on ore grade and type. It is then the task of the plant metallurgist to ensure that these ore blocks are fed to the plant in a manner that satisfies the prevailing plant constraints. This task is often completed in complex Excel® spreadsheets that are modified over time with factors applied to account for plant modifications or limitations.It is the authors’ experience that this approach is difficult to audit and replicate in a consistent manner. Furthermore, operational decisions, such as primary grind size or autoclave oxidation are made on the metallurgist or managements’ perceived optimum value and does not necessarily represent a cash flow based optimum.Many processing plants contain multiple internal constraints. As ore feed grades and properties change over the life-of-mine (LOM), processing-bottlenecks shift from one unit process to another and different operating strategies need to be adopted to maximise cash generation from the process.This paper presents a unified optimisation approach to scheduling ore based on a circuit mass balance to describe the process plant with individual models for each significant unit operation. The approach allows for optimisation over multiple input variables and the inclusion of linear and non-linear constraints.This optimisation process has been applied to different complex gold operations. The end result is an automated scheduler that selects the optimum blend of ores as well as plant operating conditions that satisfy all internal plant and shutdown constraints while maximising the objective of choice (metal production or cash flow). The models are also valuable for evaluating expansion or debottlenecking opportunities of individual processing units. These models are coded in Matlab® R2016a provided by MathWorks®, and can be deployed to end users in a compiled version with significant savings in time to run different scenarios over the Excel®-based systems.Citation:Seaman, D R, Tooher, R P and Seaman, B A, 2016. Optimisation of Complex Gold Processing Plants with Multiple Unit Operation Constraints - the Newcrest Planning Scheduler, in Proceedings 13th AusIMM Mill Operators’ Conference 2016, pp 191–198 (The Australasian Institute of Mining and Metallurgy: Melbourne)."

Oct 10, 2016

By W. Tse, D. Wong

Dense medium separation (DMS) is one of several preconcentration methods used for early waste rejection from run of mine ores at relatively coarse particle sizes prior to additional milling and beneficiation. DMS has been used extensively in the coal, diamond and iron ore industries but lab scale and pilot test work has demonstrated successful separation and upgrading of other minerals such as lead, zinc, copper and lithium based ores using DMS. This paper reviews historical dense media systems, results from the pilot scale Condor DMS system as well as associated laboratory heavy liquid separation (HLS) test work.

Jan 1, 2014

By James A. Bloom

To operate the Morris Fork Preparation Plant with a closed water circuit has been an elusive goal for Union Carbide. The benefits of a closed circuit have never been questioned. The removal of fine solids from washery water makes possible the recirculation and reuse of the water. Heavy media drag tanks and other separating machines perform better and more consistently with washery essentially free of fine solids. Finally, the production of a clarified effluent makes unnecessary the sludge ponds usually associated with a coal preparation plant. Why then do I say elusive? Because, since plant design was completed in 1970 we have been in hot pursuit of an ever-growing fine solids problem. In four years the minus 28 mesh material in the plant feed has nearly doubled. The replacement of conventional sections with continuous mining machines has led to a lowering in size and quality of product from the mine. In addition, increasing emphasis underground on roadway clean-up has contributed to the fines problem.

Jan 1, 1975

By Thomas W. Smelser

A full-scale geotechnical model of a 15-foot (4.6 m) wide coal mine entry in correlation with computer finite-element analysis (FEA) is being employed at the Bureau of Mines Spokane Research Center for basic research on roof-bolt support systems. Physical and computer modeling of various coal mine roof-bolt reinforcement systems will increase our basic knowledge of how roof supports function. This information, in correlation with computer FEA and underground verification tests, will provide a basis for establishing safer, more cost- effective roof control plans and help establish guidelines for employing fully grouted and conventional bolting systems. The basic rationale for the research, research approach, methods and equipment employed, results to date, and future research plans are described in this paper.

Jan 1, 1982

By J. Álvarez, J. Mesías, C. O. Gómez

"Operations routinely run flotation tests in laboratory mechanical cells to determine adjustments to plant operation based on feed flotation response or the effect of new reagents and dosages. The metallurgical results of these tests are certainly affected by changes in bubble size, which simultaneously impact the recoveries of the collection and froth zones. It is known that bubble size depends on the characteristics and operation of the machine in use, particularly on the gas flow rate delivered to the unit and the selected frother type and dosage. Although flotation rate constants have been related to bubble size, bubble surface area flux seems to be a more fitting variable to correlate flotation kinetics and cell performance, as it integrates bubble size and superficial gas velocity effects. However, although some evidence has been provided, a categorical relationship between cell recovery and bubble surface area flux has not been established. Our interest is to demonstrate this relationship to use it as a basis for developing soft sensors to track on-line collection zone recovery in cells. Flotation tests were designed to produce Cu concentrates for a range of bubble surface area flux values, obtained through changes in frother concentration at a constant gas flow rate, and by increasing gas flow rate at the same frother concentration. The tests were run on samples prepared from an ore batch supplied by a local operation, following strict grinding and flotation procedures, with a shallow froth to approximate cell recovery to that in the collection zone. Bubble sizes were determined using the sampling-for-imaging technique developed at McGill. The results unequivocally showed a consistent positive correlation between cell recovery and bubble surface area flux, and significant variations in performance when frother addition and gas flow rate were changed.INTRODUCTIONMineral flotation is a separation process to produce concentrates of valuable minerals by selective attachment of particles to the surface of bubbles. The process is carried out in machines where air is injected through a mineral pulp to form bubbles, and operated to create two zones: a bottom one (collection zone) where bubbles are continuously generated under conditions adequate to form bubble-particle aggregates by collision of the rising bubbles with suspended particles; and a top one (froth zone) where bubbles and bubble-particle aggregates continue to rise while concentrating and forming a froth layer for water and entrained particles to drain back to the collection zone, before overflowing as a concentrate stream. The phenomena occurring in these zones are complex and, in many cases, interactive, as they simultaneously affect stages of the particle separation sequence occurring in both zones. Although there have been significant advances in instrumentation to characterize particle and bubble populations, these have not resulted in knowledge to explain or models to describe phenomena from fundamental principles. Measurements continue to be limited to the development of empirical models for predicting the effect of operating variables on performance."

Jan 1, 2016

By M. H. Govett, G. J. S. Govett

"The current American ""energy crisis"", occurring in the midst of a global debate on the adequacy of mineral supplies to support present and projected levels of world consumption, has focused attention on Canada as a major world producer of minerals. Exports of minerals account for approximately one-third of Canadian foreign earnings; more than half of these exports are to the United States. Although the United States is a net importer of most industrially important metals, with the exception of nickel and zinc, only a small part of American mineral imports are from Canada; these imports are minerals for which geographical proximity and strategic considerations are important. In the short-term, Canada is more dependent on her exports to the U.S. than America is on imports from Canada. It is argued that Canada, far from indulging in economic nationalism to preserve her resources, should expand her exports while the markets are available."

Jan 1, 1973

By H. M. Chance

Jan 1, 1886

By Y. J. Son, S. S. Nageshwaraniyer, K. M. Kim

"This paper reports on the development of a simulation-based framework for obtaining optimal blast design parameters for a hard-rock mine. To do this, a conventional medium-sized hard-rock mine was taken as a case study. The mine has two pits containing hard and soft rock types. The proposed framework contains a combination of regression analysis using Excel software by Microsoft and discrete-event simulation using Arena software by Rockwell Automation, applied to construct a model of the material-handling network of the mine. Specifically, blasting parameters are estimated by Excel-based regression analysis, processes including blasting and haulage from pits to crushers are modeled by a Forward Blasting simulation submodel, and material-handling operations including crushing, storage in stockpile, and haulage via conveyors and into SAG and ball mills are modeled by a Crusher to Ball Mill simulation submodel. A Reverse Blasting submodel is then used to obtain the optimum blast design corresponding to a target P80 particle size. Using the proposed framework, an economic analysis was performed to demonstrate the cost savings that could be realized for each rock type as a function of specific explosive energy. IntroductionIn a modern hard-rock mine, various processes such as drilling, blasting, crushing, grinding and mineral liberation are optimized to increase productivity, a practice known as mine-to-mill (MTM) optimization. Blasting is important in MTM optimization as it is the first comminution process and has an impact on all downstream processes (Julius Kruttschnitt Mineral Research Centre, 1996; Nielsen and Lownds, 1997; Nielsen and Malvik, 1999; Chung and Katsabanis, 2000; Kim and Kemeny, 2011a; Kim and Kemeny, 2011b).Two main research topics have emerged in the area of blasting design: (1) identifying the optimal target blast fragmentation at each shot and (2) controlling the blast fragmentation for that target. As part of an MTM optimization study, Kim and Kemeny (2011a; 2011b) developed a site-specific blast fragmentation prediction model that can be used to identify the target blast fragmentation and can be incorporated into MTM optimization. They also reported methodology for assigning model parameters easily and with minimal human bias."

Jan 1, 2015

By M. Nilmani, J. Sofra

The transverse distributions of the solids discharge velocity and mass flux at the discharge end of vertical and inclined lances were measured in order to detennine the transverse distributions of the axial momentum flux, which is a dominant factor influencing the penetration behaviour of particles into melts during submerged injection. The effects of gas velocity (10 - 30 m/s), solids loading (5 - 10), lance length (0.15 - 1.0 m), lance inclination (vertical downward - horizontal) and particle density (2500 - 8900 kg/m3 ) were investigated, while the lance diameter and particle size were fixed at 10 mm and 220 µm respectively. The particle velocities and mass fluxes were measured by image analysis of particles illuminated in a laser-generated light sheet aligned vertically through the axis of the lance at the discharge point. The particle discharge velocity profiles for vertical downward flows were synunetrical about the centre-line of the lance, with the maximum velocities occurring at the centre-line. The velocities increased with increasing gas velocity, increasing lance length and decreasing particle density in accordance with previous observations. The transverse mass flux profiles were also synunetrical for vertical downward flows, however at the lower gas velocities the peaks in the profiles were displaced from the centre-line of the lance by a fractional diameter of about 0.15. The particle discharge velocity profiles become increasingly asynunetric as the lance orientation was changed from vertical to horizontal, with higher particle velocities present near the top wall of the lance. The mass flux profile also became asyrrunetric as the horizontal orientation was approached, however in this case, the profile became biased towards the bottom of the lance. The effect was much more pronounced for a gas velocity of 10 m/s than for 30 m/s, showing the relatively stronger gravitational influence as the velocity was reduced.

Jan 1, 1996

By Ryan L. Veenstra

This paper presents a modelling study of a cemented paste backfill in an underground stope. The model was developed to help provide a better understanding of what is happening in the stope during the filling stage of the stope. In order to do this, the model incorporates the paste rise rate, stope geometry, and time-dependent input parameters. This paper looks at the effect of geometry in two parts. The first part compares a series of simple rectangular stope models. These models differ in size both in two and three dimensions. The second part compares the results of four 2D models together and then to the field instrumentation data. Part of this section introduces the geometry and instrumentation within the test stope.

Jun 1, 2012

By G. Clarkson, M. Hitch, R. Clarkson

"A novel reagent-free method of extracting gold from gravity middling concentrates in the Yukon placer fields is presented in this paper. This method exploits the malleability of gold by submitting concentrates to grinding in a rod mill. Brittle waste minerals are effectively reduced, whereas malleable gold particles are flattened and are then extracted by classification through sieves. Recoveries in the field using a laboratory-sized rod mill regularly exceeded 90%, whereas correlation laboratory tests indicated recovery to be most sensitive to the mill charge size. This method has broad potential, including application to the gravity circuits of large hard-rock processing circuits.RÉSUMÉ Cet article présente une nouvelle méthode sans agents réactifs d’extraction de l’or dans les concentrés gravimétriques mixtes que l’on trouve dans les districts placériens du Yukon. Cette méthode exploite la malléabilité de l’or en broyant des concentrés dans un broyeur à barres. Les déchets miniers cassants sont bien réduits, alors que les particules d’or malléables sont écrasées puis extraites par classification au travers de cribles. Si les récupérations sur le site à l’aide d’un broyeur à barres de laboratoire excèdent 90 %, les essais de concordance en laboratoire indiquent que la récupération est très sensible à la taille de la charge du broyeur. Cette méthode présente un grand potentiel, notamment une application possible aux circuits gravimétriques des grands circuits de traitement des roches dures.INTRODUCTIONExploiting the high density of gold to separate it from waste materials is the oldest known mineral processing technique. This basic technique is still widely used in gravity concentration circuits today; however, gravity processing invariably results in high-value middlings, especially in the Yukon placer gold fields. In addition to having a uniquely high density, gold is also the most malleable metal. This unique malleability can be exploited to extract gold from otherwise inaccessible gravity middlings.The Yukon placer gold industry has been continuously ongoing since the 1860s, and today produces approximately 60,000 oz t (1.87 million grams) of crude gold annually, most of which is from the Klondike region near Dawson City (Van Loon & Bond, 2014). It is important to note that Yukon placer miners do not use any chemical extraction methods; rather, gravity upgrading methods are the sole processing techniques used. Placer deposits are typically coarse, well liberated, and naturally gravity concentrated and recoverable, thus making more expensive chemical extraction unnecessary (Mitchell, Evans, & Styles, 1997). Furthermore, a strict permitting regime, environmental concerns, lack of expertise, and fear of repercussions from regulators prevent miners from attempting more advanced processing methods, such as flotation or cyanidation. Even simple chemical extractions like mercury amalgamation have not been implemented for decades, with one observer noting that, as many as 30 years ago, “the art of mercury for amalgamating appear[ed] to be dying [in the Yukon]” (Osler, 1983)."

Jan 1, 2017

By Ralph M. Foecking

The disposal of the phosphate slimes produced by Florida beneficiation operations is perhaps the biggest single problem of the phosphate mining industry. This is an old problem which has not been solved and which is becoming increasingly severe. In a typical phosphate mining operation, the phosphate rock mined is initmately mixed with sand and clay, constituting what is known as matrix. During the beneficiation, the clay and other fine materials are separated usually at -150 mesh, and washed from the phosphate rock in a form of diluted slurry known as phosphate slimes. The quantity of slimes solids and their composition vary considerably with the location but usually represent from 25 to 35% of the ore mined. Because of the affinity that clays have for water, large volumes of water are required to separate the granular material in the matrix forming a dilute slime suspension (1.5 to 3% solids) of colloidal material, which settles very slowly, and thus requires immense impounding areas, which never becomes totally usable land. These ponds also contain about 25 to 35% of the total P205 values mined. The magnitude of the problem represented by the slimes can be appreciated better if we realize that there are around

Jan 1, 1971

This paper talks about the experiences of groups we have worked with over the last few years in the Asia-Pacific region (Australia, Canada, New Zealand and Papua New Guinea) and the ways that they have worked to bridge the divide between traditional and introduced structures, governance at a regional level and the introduction of traditional values into monitoring and evaluation practices. In doing this these groups have created structures and processes which have helped them engage both more effectively with external stakeholders while maintaining the legitimacy of their own operations with their own constituents. These are important ideas for those involved in the mining industry that could provide a number of very tangible benefits to mining firms and their engagement with these kinds of groups.

Jan 1, 2009