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By R. Niechcial

As populations grow and industry expands, the limited fresh water resources available are increasingly under stress. This situation creates conflict between communities and industry; and the sustainability of both is threatened. The symbiotic relationship between community and industry highlights the need to develop innovative solutions to these water shortages. The sea may hold the key to providing the resource to permit the development of industry, the sustainability of communities, and the protection of the dwindling legacy water resources around the world. Desalination technologies have developed to where it is now economically viable to create industrial and potable water quality from seawater. Nowhere is this development more important than in the arid region of Northern Chile, where high copper prices have encouraged a boom in mine development.

Jan 1, 2007

By R. W. Thompkins

The two largest contributors to silicosis in machine men are dust from drilling and dust from blasting. With the advent of the shatter-cut method of blasting, the evils of blasting dust were greatly reduced. The problem of dust from drilling has been attacked from two different angles: (1) The adoption of dustless frontheads or enlarged water tubes, both of which have proved capable of reducing dust concentrations; and (2) The adoption of better ventilation. Many operators are loath to adopt dustless frontheads or enlarged water tubes on Leyner drills because of the increased repair costs on drills, and also because it has been found difficult to enforce 'the proper usage of dustless machines: for example, workmen sometimes plug the vents in the fronthead.

Jan 1, 1943

By Michael Bowker

Au/TiO2 catalysts were prepared by incipient wetness impregnation and tested for the room temperature photocatalytic reforming of methanol in aqueous solution. These catalysts proved to be more active, on a molar basis, than Pd/TiO2. The dependence on loading of gold was different from that of palladium, showing a double maximum in yield at 0.1 and 2 wt. % with low rate below 0.01% and above 10%. A model is proposed for the reaction involving band gap excitation of titania electrons which are used to oxidise the methanol via adsorbed CO. With palladium, photoreforming of CO and water can be achieved, but this is much less effective on gold, presumably due to the much weaker bonding of CO on Au.

Oct 1, 2003

By M. Hamamoto, M. Furuta, S. Tanaka

The Tamano smelter and refinery has expanded its production from 228kt/y to 260kt/y since 2006. It was not a big jump, but efficient and economical improvements were executed. These were not only de-bottlenecking and modernization of the smelting plant, including the acid plant, but also additional processes were commissioned, e.g. slag cleaning furnace and steam dryer. On the other hand, a conversion to permanent cathode process in the #2 tank house made the biggest impact on production efficiency for the refinery plant. In order to overcome the drastic change of copper business, although each scale is not so big, continuous improvements are very important to survive. This paper mainly describes the recent improvements of the smelting plant.

Jan 1, 2007

By C. G. Kemsley

THE ore as hoisted is very wet, and difficulty was experienced i~ screening it to remove the fines before going to the secondary crusher. In fact, the fines had a tendency to form balls and roll down the screen, and only a small percentage was removed. Their inclusion with the other ore going to the Symons secondary crusher caused excessive spring action and pounding between the adjustment ring and main frame, resulting in abnormal wear between the two. To overcome this, it was decided to wash the fines through the primary screen, and use an Akins classifier to de-water the screenings, pumping the overflow from the classifier up to the mill and discharging the oversize onto the mill-feed belt.

Jan 1, 1945

By K. Adham, C. T. Harris

Arsenic is often associated with copper, nickel and gold in sulphide deposits. This paper describes a two-stage high-temperature fluid bed reactor for the removal and fixation of As from ores and concentrates. The first (bottom) stage of reactor removes the As through a neutral roast, by volatilization as mostly sulphide species. The second (top) stage of reactor captures the As from the gas phase through oxidative fixation, as a stable iron arsenate, by reaction with an appropriate iron source (sulphide or oxide). The second stage is placed on top of the first, so that their combined function can be achieved in a simple two-stage fluid bed arrangement, with the bottom stage off-gas providing the top stage fluidization.

Jan 1, 2014

By Mario A. Morin

The last few years have seen considerable consolidation of the mining software industry and a trend towards greater planning and production control system integration, particularly for surface mines. The mining industry is starting to realize the benefits of system integration and will continue to drive the evolutions of these systems. Several trends can now be observed. The trends include application and system integration, data portability, ?intelligent? systems for support of decision-making activities, mine process-control and automation. While many planning systems are moving in this direction, there is room for considerable improvements. This paper will discuss these trends, examine the current state-of-the-art in mine design software, and identify areas where improvements should be made and why.

May 1, 2004

By Arne Renström

A fleet management system such as Minestar with CAES and Aquila could basically be defined as a tool for production control and distribution of drill and load maps, but should also be considered as continuous improvements and a never ending production study. The objective of production studies is to establish facts to be used for production improvements. In a mine operation there are many issues to improve and they spread from achieving productions plans, drilling precision, improved spotting while loading to equipment utilisation. This gives that there is not one single key value to present; we need to manage information presented on maps, as trends, graphs, tables and pre-calculated data for ?free-use? normally in spread-sheets to be able to turn data into useful information.

May 1, 2003

By Y. Mitsuda, Y. Kayanuma, T. H. Okabe, M. Miyake

A new process to recover platinum group metals (PGMs) from automotive catalyst scrap using metal vapor was developed. To improve the efficiency of the acid dissolution process of PGMs, metal vapor of reactive elements such as magnesium or calcium were contacted with spent automotive catalyst. It was expected that metal vapor would react with metal selectively and form intermetallic compounds. The specimen of the spent catalyst was treated at 1173 K for 3 h, and it was then dissolved in aqua regia for 1 h to recover PGMs. After the reactive metal treatment, 88% of Pt, 81% of Pd, and 72% of Rh in the catalyst scrap was dissolved, while only 77% of Pt, 69% of Pd, and 38% of Rh was dissolved from untreated scraps.

Jan 1, 2004

By E. Paransky, M. Rigaud, G. Paschek, S. Palco

Some of the negative impacts of carbon addition on the strength of castables are yet to be overcome in order to fulfill its potential benefits for oxidation resistance. This paper reports the results of recent studies conducted at CIREP on the effects of different types of carbon additives on the thermo-mechanical properties of magnesia-based castables. Experimental techniques included measurements of the hot modulus of rupture (HMOR), hot modulus of elasticity (HMOE), as well as the wedge-splitting test (WST). The comparison of evolving microstructures was carried out employing scanning electron microscopy with microanalysis attachment (SEM/EDS) and X-ray diffraction (XRD). HMOR values of 12 MPa at 1300°C have been reached in MgO-Si02-C castables containing up to 7% carbon.

Jan 1, 2004

By L. Jacobsson, J. E. Lindqvist

A series of laboratory tests were conducted to study stress-induced spalling on medium to coarse-grained granite specimens. The specimens made from cylinders had two manufactured notches on opposite sides aimed to represent the tangential loading around a circular opening. Specimens of three different sizes were tested with notch radii, 98.5, 225 and 375 mm, representing 197, 450 and 750 mm diameter holes, to study the effect of notch radius on the spalling initiation stress. The cracking was monitored by acoustic emission sampling. The fracture patterns were investigated visually on polished slabs and by microscopy on thin sections. The crack analysis describes how the cracks propagate in relation to the grain structure in the rock and to the macroscopic stress field.

Jan 1, 2015

By Barbara Kirby

Mining Industry HR Challenges Mining industry needs to hire approx. 100,000 workers by 2020 Attraction and retention of talent in all occupations Mobility of skilled workers between mine sites 70 percent of employers expect labour shortages over the next 5 years. Largest shortages: -physical sciences and engineering occupations -trades and ?undesignated? occupations ?Undesignated? Occupations ?Undesignated? Occupations -eg. mill operators, production / development miners and heavy equipment operators More than 20,000 workers will be needed by 2020 in the undesignated occupations and another 11,500 tradespersons Turnover rate for trades and undesignated occupations at mines is high: 8.3% compared to 5.6 % for all other occupations There is no system to recognize the skills of high-demand undesignated occupations

May 1, 2010

By Tom Shumka

INTRODUCTION ?This bull gear inspection technique was developed to provide more accurate data and faster inspection times than current techniques used today. ?Eddy Current Array (ECA) is a non-destructive testing technique that provides the ability to electronically drive multiple eddy current coils, which are placed side by side in the same probe assembly. Each individual eddy current coil in the probe produces a signal relative to the phase and amplitude of the structure below it. ?This data is referenced to an encoded position and time and represented graphically as a C-scan image. Most conventional eddy current flaw detection techniques can be reproduced with ECA inspections; however, the remarkable advantages of ECA technology allow improved inspection capabilities and significant time-savings.

Oct 1, 2010

TIPS FOR SUCCESSFUL WASTE MANAGEMENT ? WASTE MANAGEMENT PLANS ? Define the question to be asked in waste characterization studies ? Calibrate assessments and designs with field conditions ? Ensure consistent with short, medium and long-term mine plans ? Design robust plans - goalposts and expectations will change ? Fully assess and integrate costs into economic models ? Integrate waste specialists into the feasibility and design teams ? Keep it simple and when you can?t, communicate it in simple terms ? PLAN EXECUTION ? Integrate the waste management plan into daily mine operations ? Identify the critical KPI?s , track them and set clear action triggers ? Know the difference between knowledge and data ?make sure you retain knowledge and document the important Maintain management, engineering and operational focus through the mine life

May 1, 2010

By K. J. Mintz

Conveyor belts installed in an underground mine can be a potential source of a major fire, thus the need for fife-retardant belting. A Canadian Standard, CAN/CSA-M422-M87, incorporating a small-scale flame test, a drum-friction test, a flame propagation test and an electrical surface-resistance test, has been developed to meet the varied needs of the mining industry. It is recommended that mines use Types A and B belting described in that Standard, because they will have passed the large-scale flame propagation test, rather than Type C, which does not require that test. Belting that has been approved by the U.S.A. Mine Safety and Health Administration (MSHA) may be much less fire-retardant than any Canadian approved belting.

Jan 1, 1992

By Nelson C. White

This paper summarizes the present state and future prospects of the potash industry, with special reference to its impact on production in Saskatchewan.

Jan 1, 1968

By Jeremy P. Richards

Key inputs are volatiles and heat: Slab dehydration: Breakdown of amphibole and serpentine in hydrated oceanic crust releases fluids into mantle wedge, causing metasomatism.

May 1, 2008

By Charlie Graham

Our Approach ? Industry Trends ? New Forces at Work in Mining ? Deep Mining ? Energy projects ? Air power ? Hydraulics ? Electric alternatives ? Drilling ? Productivity ? Conclusions ? Transportation ? References

Oct 1, 2010

By DALE MacGREGOR, VERA TUREK

The Blue Mountain nepheline syenite deposit has been the subject of several detailed studies. It has been variously referred to as an intrusive stock, a metasomatic deposit, an intrusive sill and a metamorphic-metasomatic body. The body is divided into six mineralogical zones, the first five being based on the characterizing accessory mineral; muscovite, muscovitemagnetite, biotite-muscovite, biotite, hornblende and pink syenite. Mining currently takes place only in the biotite zone. Foliation is particularly prominent in the central (hornblende) zone and near the margins of the nepheline syenite. Majic bodies within the nepheline syenite may represent basic rocks that have been less altered by metasomatism, metamorphosed basic dykes or sloped blocks of metasediments. The most prominent structural features are the northeast-trending folds that have been modified by later north west-trending folds.

Jan 1, 1984

By L. Sun

Recently, micro-tubular solid oxide fuel cells (SOFCs) have attracted the attention of many researchers because of their numerous advantages over larger tubular and planar SOFCs. These include excellent thermal shock properties giving rapid startup/shutdown capability, a high volumetric power density compared to larger tubular SOFCs, and reduced sealing problem compared to planar SOFCs. In order to screen cathode materials for micro-tubular SOFCs, the perovskite cathodes were deposited, using a variety of methods, on 10.5 mol % yttria-stabilized zirconia (YSZ) tubes. Their electrochemical properties were then evaluated by using electrochemical impedance spectroscopy and steady-state polarization methods, based on a three electrode configuration, and with the reference electrode position carefully optimized. The oxygen reduction reaction kinetics at the cathode/electrolyte half cell were then investigated in detail.

Jan 1, 2005