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By D J. Hill

"Mining companies routinely invest in improvements to their processing operations, but often these enhancements do not work to full effect.Improvements can be ineffectual because underlying process problems are not identified or prioritised for correction or repair.This is frequently because ‘black box’ solutions deployed to implement process control improvements typically rely on instrumentation to provide data for algorithms to work effectively, and these solutions are often ineffective or disabled at mineral processing sites.There are three key reasons they can fail to deliver: vital instrumentation is not calibrated or functioning as required basic process control and loop tuning was not implemented correctly or is in need of tuning there is an inability to support the ‘black box’ solutions on-site.Many of these problems can be overcome by implementing operational analytics that identify where problems are occurring and prioritise where improvements need to be made.Incorporating operational analytics into process improvement is not a new methodology. It is more a back-to-basics approach to make more efficient use of capital and systems already deployed.Data collection systems, such as the OSIsoft PI System, provide real-time and historical process information for process control experts to analyse and identify areas for improvement. However, most systems are not used effectively. With some simple enabling, data collection systems can provide evidence for prioritising investments in improvements and determining an investment’s effectiveness.MIPAC advocates that the initial step, with analytical evidence, is that clients review the control strategies and implement small influential instrument repairs/calibrations and operator training. This can significantly boost process productivity without the need to spend large sums of money on new capital or employing expensive, difficult to maintain ‘black box’ solutions.A simple Stage-Gate®-style approach ensures that small investments in evidence-based process improvements deliver significant benefits to mining operations.CITATION:Hill, D J, 2014. How to prioritise process improvements, in Proceedings 12th AusIMM Mill Operators’ Conference 2014, pp 307–314 (The Australasian Institute of Mining and Metallurgy: Melbourne)."

Sep 1, 2014

By Robert E. Murray

It's indeed a pleasure for me to speak to you today about the development and operation of large-scale surface coal mining projects in the western United States. It is an exciting story about American business working to solve a critical national problem -- the energy shortage -- through research, new technologies, financial innovation, and imaginative management. The North American Coal Corporation -- the second largest independent mining company and ninth largest United States coal producer -- is proud to be a part of this story. Our operations in North Dakota reflect the coal industry's Western activities. So, today, I would like to focus on our planned involvement in that state. I'll briefly survey why North American is developing large- scale surface mining in North Dakota, and I will outline the many problems associated with this coal development and how we are working to solve them. Finally, I will look at the financial and management techniques we are using to make it all work. In short, I'm going to present a case study of Western coal mining. Let's begin by looking at the reasons we are in North Dakota. The United States Bureau of Mines estimates that 44 per cent of the nation's total recoverable coal deposits underlie the three Northern Great Plains States of North Dakota, Montana, and Wyoming. We estimate that North Dakota alone has about 25 billion economically surface-mineable tons of coal with today's technology. North Dakota has the energy that could keep our factories running and our homes lighted In the years ahead.

Jan 1, 1975

By C. J. Kirkland

25th Julius Wernher memorial lecture given at Tunnelling '91, sixth international tunnelling symposium held in London, 14-18 April 1991. The title gives the lecturer a chance to share some of the lessons he has learnt in a lifetime of tunnelling and particularly in the last six years of his involvement with the Channel Tunnel and the International Tunnelling Association. These included: the difficulties of split contracts but the problems arising with Eurotunnel over the need to create a single owner to whom the banks could lend; the peripatetic nature of tunnellers who built London's underground in the 1960s and returned to build the Channel Tunnel from Egypt, Singapore, Hong Kong and Australia; the increasing requirement for strategic planning resulting in tunnels between European countries and the need for engineers to deal with decision-makers; EU work on harmonising regulations so that there need no longer be, for example, arguments over which regulations should be followed for temporary electrical equipment in the section of the UK tunnel that is technically in France; the huge improvements in safety standards and attitudes; the enormous increase in the scale of undertakings and individual contracts, with an accompanying change in attitudes to logistics; technological advances to cater for the high performance now required of equipment; and the rising importance of environmental issues. The lecturer also briefly touches on the work of the International Tunnelling Association

Jun 13, 1905

The ventilation of a mine is one of the key elements to a successful mining operation. It is, or should be, one of the primary concerns of the mining engineer at an underground mine. Too frequently, however, insufficient thought is given to future requirements. As a result, the mines suddenly find themselves with ventilation problems that cannot be corrected economically, or in short order, and have to suffer the consequences of being on the verge of having units shut down from time to time until the venlilaltion system can be improved. Insufficient ventilation in capital-intensive mining can cause production losses, the values of which far outweigh the significant costs of providing and operating an adequate ventilation plan. Many theories, and techniques in planning and control of underground ventilation systems have been developed over the years . It is the intent of this paper to point out some of the fundamental concepts, from the practical point of view, in the design and operation of a ventilation system, with special reference to underground mines using a room-and-pillar method.

Jan 1, 1986

IN 1932, the No. 4 shaft at Wright-Hargreaves mine was completed to a depth of 4,000 feet, and the lowest operating level at that time was at 3,900 feet. It was realized that the existing pumping system, using triplex plunger pumps at somewhat irregular depths in the mine, would be in-adequate to take care of the increasing volume of water that would have to be handled as mining operations expanded. Accordingly, in February, 1932, after a thorough study of the whole matter, it was decided to instal an entirely new, automatically controlled, system of pumping, employing centrifugal pumps, with their characteristically trouble-free performance, operated by off-peak power.

Jan 1, 1939

Mine site rehabilitation is the repair of the disturbance caused by mining on the immediate mining area and also on the surrounding environment. The long-term objectives of rehabilitation can vary from simply returning an area to a safe and stable condition, to restoring the mined land to a state as close as possible to its pre-mining condition, capable of being self-supporting and having a beneficial final land use. This paper investigates the importance and benefits of environmental planning, in particular for rehabilitation, and how input into daily operations can allow mining to progress with limited impact on the surrounding environment. It will also identify some of the key mistakes currently made during mining which could be averted by implementing prior planning and incorporating environmental consideration into daily operations. A number of rehabilitation opportunities will also be detailed for the different stages of the life cycle of a coal mine.

Jan 1, 2007

By C. Blais, G. L’Espérance

Characterization of second phase particles is important with regard to their influence on mechanical properties of materials. Analytical electron microscopy offers the possibility to achieve complete characterization of inclusions. Complete characterization of inclusions means quantitative evaluation of their chemistry and the stereological parameters. A characterization technique based on integrated microscopy and involving scanning electron microscopy, image analysis and energy dispersive X-ray spectrometry is presented. A discussion of the use of transmission electron microscopy and electron energy loss spectroscopy is also presented for the characterization of very small particles and compounds (>100 nm).

Jan 1, 1998

By Arthur M. Whiteside

Discussion of the laws bearing upon the economics of mining in this province at once resolves itself under three headings: (a) The rights and obligations of holders of mineral bearing lands; (b) Taxation of mines; (c) Regulation of methods adopted in financing mining operations. Titles: The law relating to titles is contained in the Mineral Act, Placer Mining Act and Coal Mines Prospecting Act. Origin: Mining laws in force in this province and elsewhere on the continent had their origin in the rule-of-thumb regulations adopted by prospectors themselves, when, far from the centres of civilization and the seats of the courts of justice, they found it necessary, for mutual protection, to fix the conditions of possession by right of location, and to prescribe the duties to be performed in order to enable the individual to maintain his ground against all comers. These regulations have been codified and added to by legislatures, until we find adequate protection and safeguard to property in the laws of this province.

Jan 1, 1924

By Robert H. Raring

Viewed abstractly, a mill may be defined as a mineral processing facility located somewhere between the mine and the tailings storage area, Just how mining operations and the demands of tailings storage affect mill design is, the subject of this paper. At the outset, it will be readily acknowledged that no two installations can, or ever will be the same. At one extreme is the bucket line dredge where the distance between the ?mine? and the tailings area is measured in terms of tens of feet. At the other extreme, the large open pit copper mines are frequently spread across twenty, miles or so of countryside with the ore moving to the mill, as exemplified by the operations at Bingham Canyon, Ray, or Ruth - the "upstream" counterparts of Garfield, Hayden and McGill. In each of these cases, mill location was largely determined by requirements for tailings storage and/or water supply.

Jan 1, 1961

By P. van der Steen

This paper examines the historical developments in diamond beneficiation technology and the impacts on the industry. The art of diamond beneficiation has given way to the application of scientific process, but at considerable capital expenditure. The shift in beneficiation methodologies has been disruptive to the traditional skills set of the industry, but evolutionary change continues and has been beneficial to the quality of the final product.

Jan 1, 2010

By E. K. Albert

In 1977, Congress enacted Title IV of the Surface Mining Control and Reclamation Act (SMCRA), providing for an "abandoned ml.ne reclamation fund". This fund, taken from a fee collected from operating coal mines, provides capital for the reclamation process. However, given the number and extent of abandoned mine sites in some states, the question of project selection is important. This paper describes a project in progress to create a Management Information System application for project ranking under multiple objectives. The benefit of this project for the need of new environmental control technologies will be discussed.

Jan 1, 1990

By I. Govender

Positron-Emission-Particle-Tracking (PEPT) has enabled the non-invasive observation of charge and slurry transport in model mills under operational conditions. We use high quality PEPT data to infer that the charge motion can be effectively described by a non-Newtonian granular fluid. An improved theory for slurry transport, including inertial effects, is presented.

Jan 1, 2012

"Hecla Limited has been investigating the potential benefits of using a Spendrup/Compact Filter Technic (CFT) diesel filtration system to remove diesel particulate matter (DPM) from the mine atmosphere to optimize use of the available air. The National Institute for Occupational Safety and Health (NIOSH) has evaluated the scrubber efficiency for dust and DPM which is to be presented in another report. This paper reports on a new mining application of a carbon particulate sensor’s ability to continuously monitor long-term mine DPM levels in conjunction with the scrubber evaluation. Magee Scientific is the manufacturer of the Aethalometer®, a continuous black carbon monitor which has been used extensively in worldwide ambient air quality monitoring networks. Two Aethalometers were used at the mine to assess their potential to continuously track underground DPM levels. In this first underground mine application, the Aethalometers were used to continually monitor black carbon (BC) in the intake and exhaust of the CFT scrubber system. Results showed that an off-the-shelf Model AE33 Aethalometer could continually track underground BC levels for extended periods of time over the course of the six-week trial. Data at the scrubber intake over 14 days of testing showed that DPM filtration would be required less than half of the time to maintain BC levels below 50 µg/m3. If the Aethalometer BC data output were “smart coupled” to control a 200-HP in-mine scrubber, significant electrical cost savings would be realized. INTRODUCTION Mine ventilation airflow quantities are calculated to maintain a safe and healthy environment for miners. Dilution of diesel particulate matter (DPM) is often a key factor used to determine the required quantities of ventilation air (Bugarski et al. 2011). DPM emissions and exposure levels are highly variable depending on mine schedules and activities (Janisko & Noll 2010); however, lacking technology to continuously monitor levels, mine ventilation systems are often over-designed in order to handle worst-case scenarios to ensure that DPM levels are maintained at or below regulatory limits. As mines go deeper it becomes more difficult to supply air, and the development of new shafts for air is not economically feasible (Basu et al. 2008). Cleaning and reuse of available air then becomes an attractive option to maintain good air quality."

Jan 1, 2016

By Peter Rubie

For many years, optimising the relining of hard rock grinding mills has been complicated by: ?? the large number of variables; ?? the low frequency of relines (slow feedback loop); ?? the potential economic risk associated with some changes. A technology that has its roots in the automotive manufacturing industry is being utilised to construct a statistically accurate, configurable, and dynamic simulation of the mill relining process. The effects of various mechanisation and process changes can be rapidly modelled and compared. This technology will provide mill maintenance managers and contract relining companies with the opportunity to benchmark current performance against world?s best practice. It will also provide an opportunity for concentrator plant designers and mill manufacturers to plan for maximum plant efficiency, by designing an infrastructure and equipment combination that maximises annual plant availability. This simulation tool and its associated data set, has been developed using recent grinding mill performance data from mills of varying dimensions, liner configurations, mill relining equipment, operator and tool variables. The simulation will provide an output that the various stakeholders can utilise to make optimal decisions within the given financial, physical and technological constraints of the individual concentrator plant.

Jan 1, 2012

By D M. Frantois-Bongarton

"A few situations are first reviewed where practical shortcuts lead to acceptable solutions where none seemed to be possible. These include: The solving of many complex sampling optimisation problems with the simple approach of the worst case policy (WCP). A simple approach to single-stage sampling problems will be mentioned at continuation. In the plants, minimising the impact of border effects in incorrect samplers, so that the resulting samples are approximately correct and acceptable in practice because the bias risk attached to them is controlled. Examples are given, as well as practical tools and a general methodology.Finally, some sources of undue conservatism are reviewed with general recommendations aiming at eliminating them.CITATION:Frantois-Bongarton, D M, 2012. Practical considerations and shortcuts in sampling, in Proceedings Sampling 2012, pp 171-174 (The Australasian Institute of Mining and Metallurgy: Melbourne)."

Aug 21, 2012

The mining industry is quite often faced with declining selling prices for its products in the face of rising prices for the input cost resources that it uses. Blasting is a key activity within the mining system and has a vital role to play within the Mine to MillTM concept. It is therefore important that blasting makes a positive contribution to mine profit and productivity. There are several variables involved in considering the profitability and productivity of blasting. The rock types and structures, the bench height, the blast hole drill rig specifications, hole diameter, spacing and burden, explosive loading and initiation and blast size fragmentation. Productivity accounting is a methodology which is used elsewhere to give additional insights into the productivity and pricing factors that drive the financial performance of a business. Miners know intuitively that productivity and pricing influence costs and profit, but only with productivity accounting can the dollars involved be calculated. Drilling and blasting are part of a chain of unit operations in a mine. For an owner-miner, drilling and blasting would be considered as cost centres and a productivity accounting cost model approach would be relevant. On the other hand a contractor is likely to consider drilling and blasting as a profit centre, in which case a productivity accounting profit model approach would be appropriate. Both of these will be explained. The paper provides a basic outline of deterministic productivity accounting and demonstrates its application to blasting. Drilling and blasting data from a mine was obtained for a two-month period. The change in productivity and prices was calculated to obtain the dollar contributions from them towards the change in cost. It was determined that although there had been productivity dollar gains these were offset by larger pricing dollar losses, the net effect being that total drilling and blasting costs increased. The productivity accounting analysis gives the facts and the mine is in a position to establish priorities based on knowing the dollar contributions of each input used.

Jan 1, 2001

By D. Brunner

System simulation is an increasingly popular technique for analyzing and improving existing as well as newly designed underground mining operations. An engineering firm that specializes in simulation helped a major metals producer build a long-range planning model of an existing underground mine. Subsequently the team adapted this model to assess technology alternatives in the design of a new mine. The two models differ in the level of detail used for modeling the development process. This paper discusses the differences in approach between the models along with the experiences gained and challenges faced during the construction and use of the models.

Jan 1, 1999

By M Scoble, E Rubio

The re-engineering of manufacturing production systems has demonstrated the benefits from using production information for optimising processes. This paper explores the techniques and issues in the acquisition and analysis of mine production data for tactical decision making in production control. The use of information and operations management tools is presented in the context of block caving studies, with particular focus on the relationship between secondary breaking and LHD production performance.

Jan 1, 2000

By Iain Sommerville, Hugh Mountford, Dawid D. Smith, Claude Dube, Brett Hixson

JW Aluminum use lean and Six Sigma techniques to continuously improve their target of reliable, repeatable and reproducible (3R) manufacturing. Six Sigma’s second stage gate, known as "Measure" involves identification and qualifying appropriate measuring systems. Metal quality (inclusions) are known in the industry to be an important element in 3R casting. The measurement of inclusions at JW Aluminum historically depended on outside vendors. In order to establish real time inclusion measurement ability within JW Aluminum, inclusion measurement systems in the marketplace were investigated. The qualification of a MetalVision MV20/20 ultrasonic inclusion analyzer are discussed as well as the subsequent application of the system in melting and casting improvement projects.

Jan 1, 2015

By C. Pritchard

John Marks said in his acceptance of the Hartman Award in 2008, "I guess that without the occasional complaint, your mine is probably over-ventilated" (Marks, 2008). Miners are seldom in this situation and spend much of the time trying to find enough air to keep an operation running. With examination, there are usually changes that can be made to increase the efficiency of ventilation systems. Mine ventilation air is a costly commodity, especially by the time it has been heated or cooled and moved to the bottom of the shaft and through the mine airways. Modifications that result in surplus mine ventilation air could bring financial and environmental benefits. Some issues mine operators have needed to address recently are increased airflow requirements to dilute diesel particulates in metal and nonmetal mines, to ventilate reserves that are deeper, hotter, and further away from fans and shafts, and to meet demands from increased production. This paper discusses successful methods to find additional usable air when there is no extra ventilation capacity. Most of the options presented in this paper are useful for metal/ nonmetal operations but some may be applicable to coal as well.

Jan 1, 2010