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By C. A. Campbell

"There has been a significant reduction in maintenance hours and improved performance by maintenance crews at the MacLeod mine since the introduction of a Maintenance Control system which includes the use of maintenance standards. This paper deals with the steps taken to develop and implement the program. The objectives of the program and the organization and training of the control group are outlined. The work-order system, standards application, classification of work and the preventive maintenance procedures will be discussed.All maintenance information is processed on a Model 360-20 IBM computer, which turns out maintenance records and control reports for management action. Information in these reports, and reasons for reporting, will be discussed and the benefits resulting from the program reviewed."

Jan 1, 1973

By S Sokhanvaran

Electrodeposition of silicon from a cryolite based electrolyte at a relatively low temperature (1000°C) is a promising approach to generate high purity silicon. In order to obtain fundamental data pertaining to electrowinning of silicon from Cryolite?SiO2 melts, density and electrical conductivity measurements were made. A range of temperatures and SiO2 contents was studied for each property. It was found that while density has an inverse relationship with temperature, the dependence for electrical conductivity is direct. Increasing silica content up to the saturation limit (~ 5 wt%) increases the density whereas further increase in SiO2, lowers the melt density. On the other hand, the conductivity is lower for the melts with greater SiO2 content, at any temperature.

Jan 1, 2011

By R. H. Knudsen

"In view of the chronic overcapacity problem in the world potash industry and Saskatchewan's recent emergence as a major producer, the long-term outlook for potash productive capacity and consumption is of importance and interest to both the Saskatchewan Government and the potash industry. This paper is based on a report recently published by the Saskatchewan Department of Mineral Resources on projected world potash productive capacity and consumption for the ten-year period 1970 to 1980. Potash productive capacity and consumption are estimated on a country and regional basis and projected annually to 1980. Tables and graphs are included which summarize projected capacity and consumption for the period and illustrate the impact of Saskatchewan's capacity upon the North American and world potash industries."

Jan 1, 1973

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 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 P. D. Soares, H. R. Bullis, R. A. Hureau

"Echo Bay's Lupin Operation has produced more than 2.15 million ounces of gold since start-up in 1982. The mining method used to the£ present time has been longhole open stoping using trackless equipment. Because direct measurement of the open stopes has not been possible until recently determining the exact quantity of unplanned dilution in previously mined stopes has not been possible. Estimates of dilution hove been mode using comparisons between production tons and grades against ore reserve tons and grades.This paper discusses tracking of grade and tonnage measurements from reserve estimation through production. Comparisons between estimated and actual tons and grade are presented~ along with a brief description of methods used at the Lupin operation to control dilution."

Jan 1, 1994

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 K. G. Davies, M. J. Royea

"A major program of pillar recovery at the Sullivan mine has been assisted for the past several years by a concerted series of rock mechanics investigations. The object of these investigations is to measure the parameters of rock behaviour which influence pillar mining. This quantitative information is then used in the design of mining methods appropriate for various conditions.Instrumentation to measure absolute rock stress, changes in rock stress and the gross deformation of rock masses has been developed. Various instruments are described, as are instrument evaluation procedures and typical test results. The data from underground measurement projects have been used to modify pillar extraction sequences along re-treat fronts. Rock mechanics information from individual pillars has been incorporated into the design of mining methods to suit particular circumstances."

Jan 1, 1968

By Yoshimasa Funakawa, Kazuhiro Seto, Akio Kobayashi

A new hot rolled high strength steel consisting of ferrite matrix and nanometer¬sized precipitates was developed. The ultra fine precipitates were identified as TiMoC2, and the strengthening by the precipitates was evaluated more than 300MPa in case of TS/800MPa grade steel. Due to the strengthening effect of the ultra fine precipitates, alloy elements for solid solution hardening can be reduced. It is notable that the steel shows very high yield strength (730MPa in case of TS/800MPa) and very high local elongation leading to excellent stretch flange formability at the same time. The mechanical properties of the steel are attractive for chassis parts and structural parts of auto body. The steel has been produced commercially, and applied to the parts successfully.

Jan 1, 2004