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By James J. Holmes

ACCIDENT prevention as we know and understand it today is of comparatively recent origin. As a matter of fact, the Industrial Accident Prevention Association of Ontario, which is the oldest organization of its kind in the Dominion, celebrated its thirtieth anniversary only this year. On the other hand, one could say that the history of accident prevention is almost the history of mankind itself. In a general sense, every forward step that man has made throughout the centuries has been largely due to two things: (1) a desire for increased comfort, and (2) the need for safety; and, always, the need for safety has taken precedence over the desire for comfort. While it is true that hundreds of volumes have been published, dealing with the many aspects of accident prevention work, you cannot go to a library and pick out a book that has all the answers in it. Such a book has never been published-we are still looking for some of the answers. However, a good deal of real progress has been made.

Jan 1, 1945

By Manoj Khandelwal, Bright Akuinor Tsidi, Newton Amegbey, Daniel Mireku‑Gyimah

One of the ambient effects of production blasting is flyrock. To effectively manage flyrock throw distance in mining, there is the necessity to successfully envisage blasting output without sacrificing the hazardous impact of flyrock which may result in fatality and operational shutdown. For flyrock throw distance prediction, velocity of detonation (VOD) and charge per bank cubic meter (CPBCM) are not usually included. This paper focuses on the use of support vector machine (SVM) regression to ascertain the impact of VOD and CPBCM on flyrock throw predictions. The machine learning models were linear support vector machine (LSVM), quadratic Gaussian support vector machine (QGSVM), fine Gaussian support vector machine (FGSVM), medium Gaussian support vector machine (MGSVM), and cubic Gaussian support vector machine (CGSVM). The outcome indicates that FGSVM was the most sensitive with a 4% improvement when VOD and CPBCM were included. As a result, the LSVM model provides a suitable AI competitive alternative tool for flyrock throw prediction in mining operations by incorporating VOD and CPBCM.

Feb 10, 2024

By M. Kane, B. Bissonnette, D. Hodouin

"A laboratory cell has been designed for a careful investigation of gold ore cyanidation using mathematical modelling of the process kinetics. The cell is a stirred vessel with continuous monitoring and control of pH, oxygen and free cyanide contents. Samples are automatically extracted for gold analysis. The instruments are connected to a microcomputer which records all the measured variables and calculates the reagent consumption (air or oxygen, cyanide, lime). For cyanide control a sample is automatically extracted and filtered and the solution analyzed, using a specific electrode, by a flow injection technique. The rate of gold dissolution is modelled using a kinetic model the parameters of which are calculated by a non linear least-squares technique. The parameters of an empirical model of reagent consumption are also estimated. The resulting model is used in a simulator for gold cyanidation plant design, tuning and control.INTRODUCTIONThe leaching of gold ores in a cyanide solution is the usual method for gold extraction from raw ores. This process requires long reaction times and leads to very significant consumption of cyanide. The optimization of the cyanidation plant operation is a very important aspect of gold ore processing for increasing gold recovery and decreasing operating costs. The key parameters to the improvement of gold extraction are the selection of an efficient solution chemistry, the design of the size and the arrangement of the equipment and the correct tuning of the operating variables. Automatic control strategies can then be applied to maintain industrial operations at their optimum setpoints.Two approaches can be used for optimizing design and control of cyanidation circuits, either empirical trials for improving process performances or mathematical modelling of the process kinetics for subsequent analysis, simulation and optimization. The advantages of the second approach, which is used in this study, is that it gives a systematic pattern to interpret data and reliable tools, in as much as the models are good, to improve operation performances. In order to determine the structure and the coefficients of cyanidation models, well controlled measurement and calibration procedures must be used. The purpose of the paper is to present an equipment and a test procedure for modelling the kinetics of gold ore cyanidation."

Jan 1, 1990

By K. Duffy, W. Valery, L. Pyle, P. Holtham

A conceptual scoping study was conducted to investigate pre-concentration options for upgrading ore from an Ag-Pb-Zn deposit. The low grade of the ore would result in only modest economic returns, given current market conditions. Several pre-concentration options were considered. These included: selective mining, crushing and pre-screening (following either standard or high intensity selective blasting), bulk ore sorting, particle sorting, jigging, dense medium separation, or combinations of these approaches. Flowsheets were developed for each option, and the upgrade performance was modelled using Limn to determine mass balances and stream tables. Due to the limited availability of test work data, the models were based not only on what test data was available but also on case study data found in the literature. The Bazin technique was used to derive assay by size data for different streams following crushing. Equipment lists and preliminary layouts were established based on the stream tables, and capital and operating costs were estimated for each flowsheet. This information was used to carry out a preliminary economic evaluation using net present value and sensitivity analysis. In this case, the most economically attractive process was found to be particle sorting; although further benefits may be realised by combining with bulk sorting. This paper describes the methodology used and the key findings of the study. Keywords: Pre-concentration, pre-screening, ore sorting, jigging, Ag-Pb-Zn, particle sorting, bulk ore sorting

Jan 1, 2020

By Jose Maria Rodriguez-Ibabe, Ronaldo Antonio Neves Marques Barbosa, Douglas Glenn Stalheim

Major costs in the production of both flat and long commodity grade structural steel products include alloy, labor and energy. Flat and long commodity grade structural steels such as ASTM A36, ASTM A527Gr50, S235, S275, S355 and other equivalent world societal standards represent over 500 million annual tons worldwide. These simple commodity grades consist of a minimum of three base common alloying elements, carbon, manganese, silicon and then can be supplemented with microalloying elements of either vanadium or niobium. Since 2016 raw material costs for two of the five alloying elements in these commodity grade structural steels, FeMn and FeV, have risen significantly and/or have become volatile making it difficult to maintain stability in profitability for these commodity grades. For steel plants producing hundreds of thousands and in some cases over a million tons annually of these common structural steel grades because of the significant alloy cost increase for Mn and V alloy additions has squeezed profitability of these grades. These grades typically represent the base loading for cost controls in most all steel plants and hence a significant cost increase or volatility in two of the five elements used for these grades having a negative effect on overall production costs. However, with a proper strategy for alloy designs working in conjunction with the mills existing processing capabilities to achieve the desired end metallurgy/mechanical properties, alloy costs and operational efficiencies can be realized.

Oct 1, 2019

By Partha Sircar

"For Berth 22 modifications at the Port of Oakland, nearly 600 octagonal 24-inch ‘diameter’ precast-prestressed concrete piles were driven, some piles over 160 feet long. Prior to production pile driving, an indicator/test pile program was performed, which included extensive use of dynamic load testing with (Pile Driving Analyzer (PDA) & CAPWAP analyses. The indicator test-pile program resulted in requiring significantly longer piles than the original design based on subsurface borings. The cause of this discrepancy is investigated in light of the available geotechnical information, soil mechanics principles and standard techniques for pile capacity computations. Several interesting phenomena emerged. These include relatively low resistances offered by crushed rockfill than would conventionally be assumed, non-homogeneity of an apparently uniform formation and the effects of jetting on pile side friction. Also revealing was the significant increase in capacity between 1 and 3 weeks of driving for long piles in clay. Recommendations were developed for pile capacity for future use as “lessons learned”.IntroductionThe foundation for the replaced Berth 22 structure at the Port of Oakland in California involved driving approximately 570, 24-inch octagonal precast prestressed concrete piles. A plan and a section for the pile locations are presented in Figure 1.The ultimate loads on the piles used in the design are presented in Table 1 – the loads are quite heavy.The foundation design was followed by an extensive Indicator Pile Program. The contractors (Manson Construction Co. of Richmond, California) opted to use a Delmag D62-02 diesel hammer (Rated Maximum Energy – 165 kip-feet). Per the project specifications, the same hammer was used for both indicator and production pile driving. The production piles of appropriate lengths were ordered based on thr results of the Indicator Pile Program. A number of interesting results were found from the Indicator Program, which is discussed in this paper."

Jan 1, 2015

By Oliver Bowles

[Simple systematic accounting that adequately records all transactions has long been regarded as essential to the welfare of any business enterprise. Some of the defects that detract from the prosperity of the slate industry are attributable to a lack of effectiveness in cost keeping. This condition has promoted the United States Bureau of Mines to make a detailed study of accounting methods for the slate industry, and to present for consideration a system of accounts, which it is believe would enable the industry to attain more economical management and operation if accepted by a fair proportion of its important units. The method of accounting presented herein has been worked out with the assistance of leading slate producers and the recommendations are tentative and are submitted in this form as a means of developing constructive criticism. Believing that cooperative effort in this, as in many ether problems will bring the most enduring benefits to the industry as a whole, the writer urges that the cost earnest consideration be given to this vital problem now facing the slate industry.]

Jan 1, 1929

The AusIMM came into being to foster the spread of professional knowledge within its client industry. It has evolved along with the Australian mining industry for more than a century. If the AusIMM is to become the world's premier mining professional body (whether by design, or by default), then draw up a strategic plan to get there. Define your strengths and market them Define the priority areas for professional competence which we most need, Target the groups within Australia who can produce the people, Create an industry peer group to speed technology transfer.

Jan 1, 1994

By T Elms, R Beckman, M Sampson

"In today’s mining industry, the pressure of reducing costs and increasing production while maintaining high safety standards is at the forefront of operational endeavours. A combination of specific mining knowledge and technological advances has helped enable this notion. Fleet management systems have been developed to enable sites to better measure and manage production to improve operational efficiency.The integral part to managing production is having accurate, readily accessible data. This empowers key stakeholders in the management team to drive production reporting, materials tracking and budget forecasting.If a site does not run a fleet management system, manual input is heavily relied upon for production data, which introduces increased risk of human input error. Errors can drive outcomes that don’t achieve increased production at a reduced cost. Alternatively, a fleet management system can have improved accuracy but involves a high monetary investment. Such an investment is not always feasible for smaller mining operations subject to current industry cost pressures.The Emeco Operating System has been developed in alliance with sites such as the Mungari White Foil Operations by satisfying the criteria of a low intensity hardware installation, material tracking data validation processes, remote monitoring, identification of metrics to improve overall operating efficiency and providing the right information to key stakeholders.Citation:Beckman, R, Elms, T and Sampson, M, 2016. Getting Accurate Mine Information to the Right Teams to Drive Production Improvement, in Proceedings Ninth AusIMM Open Pit Operators' Conference 2016, pp 203–211 (The Australasian Institute of Mining and Metallurgy: Melbourne)."

Nov 15, 2016

The first grant of land rights in Australia was pursuant to the Aboriginal Land Rights (Northern Territory) Act 1976. That Act has been at the core of the dispute between land rights and miners' rights. The mining industry believes that the Act, in giving a right of veto to Aborigines with respect to exploration and mining on Aboriginal land, has been responsible for a stagnation in exploration amd mining activity in the Northern Territory. In February 1985 the Commonwealth Government released for public comment its preferred model for national land rights legislation. The model has been opposed by the mining industry because it believes, first, that land rights is a matter which should be left to the States and, secondly, that the detailed mechanisms contained in the model constrain the industry in the manner of the Northern Territory legislation. Aboriginal leaders have opposed the model because it does not, in their view, measure up to undertakings given by the Commonwealth Government and, in addition, it provides for amendments to the Northern Territory legislation which are likely to result in the loss of the Aboriginal veto right. Are land rights and miner's rights compatible? The answer is yes provided all parties, including Governments, are prepared to talk and compromise and Governments recognise that the grant of land rights and any control by the Aboriginal people of exploration and mining on their land is not a substitute for raising the living standards of Aborigines as a significant group of disadvantaged Australians.

Jan 1, 1986

By Didier Fohlen

Three Policy Shifts to enhance IFC?s Accountability ? Comprehensive and dynamic treatment of social, health, safety and environmental risks ?Covers a range of risks encountered by clients in emerging markets ?Framework to anticipate risks and to address them as they arise ?Includes community development, biodiversity, human rights ... ? Effective principles to guide an outcomes-based approach ?By clients and IFC ?Focus on broad community support and value-added sustainable development initiatives Enhanced governance, transparency and disclosure

May 1, 2006

By Chad W. Brown

"A study of five commercially available solvent-extraction diluents in combination with three commercially available extractants under sub-Saharan African copper solvent-extraction conditions yielded intriguing results. A variety of physical and chemical property analyses showed that the diluents have some property differences, but overall the properties are similar and provide comparable solvent-extraction performance. Although each physical chemical property technique provides useful information, no individual test result suffices for prediction of diluent performance. Furthermore, a diluent should be evaluated within the conditions for which it is targeted to determine a true measure of performance. Overall, the diluents studied possess appropriate physicochemical properties for sub-Sahara Africa copper solvent-extraction conditions and can be utilized to achieve efficient, safe and reliable operations. INTRODUCTION Background Today, commercial SX diluents are available globally from a limited number of manufacturers. Production quality and consistency of these diluents have improved tremendously over the past 20 years. For example, diluent flash points have been increased incrementally to improve transport and handling while reducing fire hazards. In addition, properties have been successfully modified to minimize evaporative losses, ultimately reducing SX plant raw material costs. Diluent manufacturers have also focused on meeting performance requirements of SX plants, including eliminating components detrimental to SX operations, such as olefinic groups that can react with various species resulting in changing phase-disengagement properties over time, as well as ensuring that proper hydrocarbon components are present within diluent mixtures to maintain good reagent–metal complex solubility. These challenges have been met in the midst of ever-increasing stringent environmental regulations. Sub-Saharan Africa copper SX operations pose a unique set of conditions for diluents due to inherent ore compositions and the associated high reagent concentrations required for complete copper extraction. Chevron Phillips Chemical Company, LP has been manufacturing hydrocarbons and hydrocarbon-based diluents since the mid-80s, applying this experience to identify the physical properties considered crucial for proper performance in SX operations. This paper documents the findings of a study utilizing commercially available diluents in combination with extraction reagents commonly utilized in African SX operations to evaluate the relative performance of the diluents under sub-Saharan Africa copper SX conditions."

Jan 1, 2015

By Siyabonga Malevu

Chemical Initiatives? Umbogintwini plant is the production facility of Chemical Initiatives? business. Umbogintwini?s J Plant manufactures sulphuric acid. The plant was designed and built by Simon Carves, and was commissioned in 1974. The plant was designed to produce 500 tons/day of Sulphuric acid (H2SO4) at maximum rates. The Sulphuric acid manufacturing is through the famous contact process whereby liquid Sulphur is injected through dried air in a burner operating at 1000 °C to form sulphur dioxide (10.5% SO2). The SO2 gas is then cooled in waste heat boiler no. 1 before being fed to a four pass converter which provides 99.5% SO2 conversion to sulphur trioxide (SO3). The SO3 gas is the absorbed by 98.5% H2SO4 through the inter-pass & final tower to make more concentrated acid and dilute it with water back to 98.5% H2SO4 in acid pump tanks and dispatched to storage tanks. The manufactured Sulphuric acid is supplied to a variety of industrial manufacturing customers includes Pulp & Paper industry, Mining industry, Chemical manufacturing industry etc.

Jan 1, 2009

By D. Noort, M. Dawborn, D. O. del Castillo

This paper was originally presented at the North American/9th US Ventilation Symposium, June 2002, Kingston, Ontario, Canada. Reprinted with permission of the publishers, A.A. Balkema Publishers, Rotterdam, Netherlands. This paper is a study of the ventilation, cooling and refrigeration system design of the Mindola copper mine in Zambia. The challenges that were addressed varied from the restrictions imposed by an ageing infrastructure to the requirement for increasing the annual production rate, coupled to the introduction of a higher level of mechanization while maintaining acceptable conditions and limiting total ownership costs. A description of how the ventilation, refrigeration and cooling systems were modelled in order to obtain the projected heat loads associated with two different mining methods over the life of the project. The methodology included a number of iterations to optimise the design and include aspects such as the expected inrush of hot fissure water, the operation of diesel machinery at depths in excess of 1500m below surface, developing a cost-efficient cooling strategy and selection of the refrigeration machinery to meet the requirements imposed by the cooling strategy. This paper demonstrates the successful implementation of an integrated design approach.

Jan 1, 2005

By K. J. Cathro

A hydrometallurgical process is described for the recovery of copper from chalcopyrite concentrates. The process is based on a cupric chloride leach, the concentrate having first been "activated" by heating it with sulphur at a temperature near 400°C. This activation process converts most of the iron of the chalcopyrite to pyrite, which is insoluble in the cupric chloride leachant. The copper is converted to the mineral idaite, which dissolves readily in hot cupric chloride: at 106°C, 98% of the copper is extracted in a three-stage countercurrent leach, the leaching tirqe being 1 hour per stage. The sulphur of the chalcopyrite appears as elemental sulphur, which is recycled for the activation of further concentrate, the final leach residue consisting of pyrite, plus the gangue present in the original concentrate. The copper extracted can be recovered by electrowinning, using a diaphragm cell. Current efficiency (one-electron basis) is about 70% but the cell voltage is only about 1 V, so that power consumption is three times lower than for the conventional sulphate electrowinning process. The leachant is simultaneously regenerated in the anode compartment. The behaviour of minor elements in the concentrate has also been studied.

Jan 1, 1976

By Lloyd A. Morley, Robert Stefanko

This report was prepared by The Pennsylvania State University, College of Earth and Mineral Sciences, ' Department of Mineral Engineering, University Park, Pennsylvania, under USBM Grant No. GO-133077. The grant was initiated under the Coal Mine Health and Safety Research Program. It was administered under the technical direction of the Pittsburgh Mining and Safety Research Center with Mr. G. J. Conroy acting as the technical project officer. Mr. J. A. Herickes was the grant administrator for the Bureau of Mines. This report is a summary of the work recently completed as part of this grant during the period 19 June, 1973 to 17 June, 1975. This report was submitted by the authors on 18 July, 1974. This technical report has been reviewed and approved.

Jan 1, 1974

By T. Owen

Not since 1917 has a foreign company developed a standalone, grass roots gold mine in Russia. With. Russia's political changes of the late 1980s, development of mineral prospects once again beckons foreign investors. In 1990, Cyprus Amax began aggressively searching for such an opportunity. Early in 1997, production will commence at the Kubaka gold project located in the Russian Far East, near the Arctic Circle. The Kubaka project is a 1,750-tonne per day open-pit operation that will produce more than 300,000 ounces of gold per year. This paper discusses the challenges of locating such a prospect, doing business in Russia, developing supply lines, identifying work force capabilities, gaining government approvals, securing financing, arranging for gold sales and ultimately building a facility in this arctic region.

Jan 1, 1997

By Charles B. Kenahan

Vanadium is subject to only light corrosion in phosphoric acid at temperatures up to 60° C. and has a moderate corrosion rate in this acid at 100° C. It is relatively corrosion resistant in sulfuric and hydrochloric acids up to 60° C, but corrodes rapidly at 100° C. It corrodes rapidly in dilute nitric acid at 35° C. Vanadium is almost inert in 10-percent solutions of formic, acetic, lactic, tartaric, and citric acids; in 9-percent oxalic acid it corrodes slowly up to 60° C. and rapidly at 100° C. Vanadium is resistant to corrosion in substitute ocean water, tapwater, and in 3-percent sodium chloride and 10-percent sodium hydroxide solutions. It is readily attacked, however, by 20-percent ferric chloride, 20-percent cupric chloride and 5-percent mercuric chloride solutions. Vanadium is protected by contact with magnesium, aluminum, and steel SAE 4130 in substitute ocean water, by magnesium and aluminum in 3-percent sodium chloride solution, and by magnesium in tapwater. Vanadium protects copper in substitute ocean water. When vanadium and stainless steel are coupled in sulfuric acid solutions, both metals are usually unaffected by contact, whereas the corrosion rate of titanium in sulfuric acid is greatly reduced by contact with vanadium.

Jan 1, 1962

The Cadia Mine is located 25kms South West of Orange in the central west of New South Wales (NSW), Australia (Figure 1). Orange is a major regional centre with a population of 35,000 people. Cadia has a history of mining and exploration dating back to 1851 and shortly after the first Australian gold rush at Ophir, north of Orange. Newcrest Mining commenced an exploration program at Cadia Hill in 1992. This identified a substantial zone of copper and gold mineralization. Subsequent resource definition drilling defined an orebody with a mineable reserve of 200 million tonnes of ore with an average gold grade of 0.74g/t and 0.17\ copper. A full feasibility study commenced in 1994, approvals to proceed with development were granted in September 1996 and the processing plant was commissioned in July 1998. The project came in on budget at A$440 million and on time, 24 months from design to construction. The estimated operating cost at the time of commissioning was A$8.85/t of mill feed.

Jan 1, 1999

By Edwin H. Bentzen

Talc, as a mineral, is rather widespread, but as an ore sultable for mining, it is rather limited. Materials sold as "talc" range from the impeccable white material from Italy to a gray-green-bluish material from Virginia. Some uses of the material called "talc" seem to be determined by the color of the material, some by the chemistry of the material, and some by the particle size of the ground material. But, there seems to be some overlapping of criteria used to judge the acceptability of a raw material. So then, any producer of talc material that is not a consumer of this raw material is faced with the age-old problems: "what do I call the stuff, and to whom should I try to sell it?" The answer to the first part is easy: if you want a high price, call it "talc"; if you want a low price, call it "soapstone". This may seem like a very simplified answer, but it is apparent that some of the products sold as "talc" have more than a minor amount of impurities in them; whereas, if they were called "soapstone", these same products would probably get a lower price.

Jan 1, 1973