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By C. A. Grandison

The economic evolution from an agrarian society to an industrial and service-oriented economy is apparent to most students of history. The long-term trend is almost taken for granted, it does not require explanation — it is accepted as the nature of man to improve his standard of living. However, there are fluctuations around this trend line which have provoked a great deal of thought. The ability to understand and control these fluctuations would yield many benefits, it would eliminate economic waste and public hardship, and would no doubt make a few fortunes. I f it is not possible to control or eliminate these fluctuations, then a reasonable forecast of the tinting, rate of change and magnitude of the fluctuations would be invaluable to industry and government.

Jan 1, 1976

By J M. Wallis

Heavy mineral sand exploration drilling prior to the 1970s generally utilised open hole auger and air-blast type drilling. However, mining reconciliations were poor and limitations on accuracy and precision of drilling results were severe.Working with the exploration companies, Wallis Drilling principals designed various systems, including what was termed the ‘Eneabba System’ and then the ‘Capel Twin-Tube System’. Eventually the company with its improvements developed and patented the Aircore Drilling System.Aircore drilling has subsequently become recognised as an excellent drilling system for exploration and mine-sample drilling that gives good precision and accuracy in sampling both above and below water. Its use has also been extended to many other commodities and is used in a number of overseas countries.This paper documents anecdotally the development of the system, identifying problems encountered during the times it was evolving and of the means to overcome the problems as being the documentation of the story by the inventors and developers in Wallis Drilling Company. Aircore drilling system is a Western Australian technological development owing its existence to the designing and incorporation of a number of discrete improvements along the way and recognises the tenacity and inventiveness of all who contributed to the system, in both Wallis and also in a number of companies that gave the impetus to succeed.

Oct 5, 2011

By David Conover

Technological advancements in electronic sensors and mine-wide monitoring systems have improved remote monitoring and analysis of underground mining information. The effective use of . these systems for ground control applications, however, remains a challenge facing the mining industry. The U.S. Department of Interior, Bureau of Mines is conducting research, utilizing real-time acquisition of rock mechanics data, to provide mine operators the means to rapidly identify and manage potentially hazardous ground conditions. The Bureau has installed a remote monitoring network in a Colorado coal mine to record Pressures from instruments installed in the roof and pi1lars of gateroads and from transducers on shield-legs along the face. The field data are being monitored at the Denver Research Center, 150 mi from the mine. A computer at the Center analyzes the field data and generates graphic displays, which permit detailed examination of mine-wide ground conditions in real-time. For the first time, Bureau researchers are able to perform real-time monitoring and analysis of rock mechanics data while mining is in progress. The data collection and display capabilities of the system were effectively used to identify and evaluate face stability problems at the mine.

Jan 1, 1990

By T. Rigg, J. N. Stone

"The process described has been developed to utilize low-grade scrap -turnings, borings, tin cans and other types of ferrons scrap which currently has been of limited or no use in conventional steelmaking processes. If scrap of this type can be converted into high-purity iron by chemical means then there is a potential saving of several million tons of metal annually in North America.The process is chemically quite simple and consists of dissolving ferrons scrap in hydrochloric acid, followed by evaporation and crystallization of the resultant solution to yield ferrons chloride crystal.s. These crystals are dries, briquetted and converted to non sponge by reduction in hot hydrogen. The HCl produced from the reduction step. is absorbed in water and the hydrochloric acid so produced is returned to the dissolver circuit. The hydrogen produced from the initial dissolution of the scrap is used to reduce the ferrons chloride. Purity is maintained by bleeding off impure chloride solutions from the evaporator-crystallizer circuit, and converting these chlorides to oxides and HCI in a high-temperature spray roaster. The HCl produced in the roaster is absorbed in water and the hydrochloric acid returned to the dissolver."

Jan 1, 1970

The extractive industry has the potential to impact the health and well-being of workers, families and surrounding communities. In the current environment of social performance, project planning considers that activities should be conducted in the best environmentally, socially and economically acceptable way across the development cycle (i.e. from exploration ? post-closure). In this context, health impacts of mining can be mapped and extend over the Life of the Community and can encompass worker injury and disease, exposure to communicable and non-communicable diseases, and health outcomes specific to family and community health and well-being outside the fence. To contribute to an emerging field focused on Health and the Extractive Industry, this paper reviews and compares health activities extracted from social and environmental reports published by selected major mining, oil and gas companies with operations in Australia and Canada. The objective of this review is to map corporate approaches to public health management across our previously developed Life-of-Mine within Life-of-Community (LOMLOC) framework in order to identify and compare trends and behaviour in corporate health investments across the project cycle, as well as identify the level of prevention targeted by this investment activity (i.e. primary, secondary and tertiary prevention of detrimental health impact). With the extractive industry facing ongoing rapid growth worldwide, this paper provides preliminary comparative information about corporate health spending by some companies in Australia and Canada. This information serves as a resource for minerals industry managers, civil society and regulators regarding current health management approaches in this sector.

Aug 1, 2013

By G J. Delemontex, N J. Grigg

Pre-concentration of precious metal and base metal ore types is becoming more relevant with the discovery, development and operation of many lower grade deposits around the world. The fluctuations in metal prices expose many mines to risks especially dealing with low and variable ore grades.Pre-concentration, the process of concentrating the valuable metal into a smaller mass yield, effectively results in the introduction of higher feed grades to milling circuits. Gangue Rejection, the removal of lower S.G. waste rock from the circuit not only results in higher downstream grades but also potentially removes harder, non-valuable mineral, providing significant power savings within the circuit. The pre-concentration or ‘gangue rejection’ process offers a number of benefits when considering the treatment of marginal ore deposits, especially if it can be performed at a coarse crush size; these benefits include a reduction of the operating costs and the feed of more metal units to the mill.Gekko Systems has effectively utilized the Inline Pressure Jig (IPJ) to pre-concentrate the valuable metal, achieving high primary recoveries into a range of mass yields resulting in upgrade ratios between 2 and 10 times.This paper explores the benefits of pre-concentrating ‘marginal’ ore deposits prior to the milling circuit; the selective rejection of ore types that may affect either the recovery or comminution process, and also looks into the potential to effectively reduce the ‘cut-off’ grade when considering the mine planning process. Case studies of projects using the IPJ to pre-concentrate and reject gangue are also included.Pre-concentration and gangue rejection provide the potential to develop marginal ore deposits, thus providing higher grades, less gangue and more metal at a lower operating cost to producers.CITATION:Grigg, N J and Delemontex, G J, 2015. The pre-concentration of precious and base metal deposits using the Inline Pressure Jig – higher feed grades and more metal, in Proceedings MetPlant 2015, pp 296–310 (The Australasian Institute of Mining and Metallurgy: Melbourne).

Sep 7, 2015

By Gareth Barnes

Traditional approach to improvement is driven by good ideas from good people, but whilst the business case may sound good, when the project is complete, we often have not delivered on expectations.  Why not? The best way to successfully predict the outcomes of an improvement effort in a complex process is through using statistical modelling, which considers the impact of uncertainty within interacting processes.  Applying Theory of Constraints in a model helps leaders to quickly determine: Where the constraining process(es) is/are Where improvements will add the most value How much improvement should be targeted - before the next constraint takes over The confidence level of achieving a given target, which gives us a clear pathway to improvement. This paper presents an analysis of statistical modelling applications at Vale’s Manitoba Operations to achieve the 2025 targets. Using statistical modelling of the Business Structure, the team identified a series of process improvements through a Theory of Constraints Analysis. Value Stream Maps (VSMs) were used to define the required data, apply statistical modelling, and conduct training sessions enabling the Manitoba team to identify the constraining influences. Scenario testing in the Statistical models helped identify the Hierarchy of Constraints and specify the pathway to improvement. How to Improve a Business Video link https://vimeo.com/344418155

May 4, 2025

By W. C. PAGE

AS the pioneer operation treating the mixed lead- zinc-iron ores from the district tributary to the Salt Lake Valley, the International Smelting Co.'s plant has offered an extremely interesting and instructive opportunity to study some phases of this problem. Basically, there were two main reason for our attempting to work out a successful operation for the separation and concentration of the values contained in the rather widespread deposits of these so- called lead-zinc ores. In the first place, the time was ripe and demanded some method of curtailing the economic waste resulting from the costs of past and present practice of smelting ores of this character, or rather, those ores which could stand the charges inherent with smelting them. Secondly, but rather primarily with us, we believe that such a solution would greatly in- crease in general the production of lead in the district tributary to the Salt Lake Valley. It is generally known that there were and are three relatively large lead smelting plants in the Salt Lake Valley and the decreasing production of correspondingly clean lead ores was not efficient to justify the existence of all three. We could not hope for better lead smelting metallurgy nor more efficient business management than was being practised, so the only prospect was to at- tempt to work out some way to increase the primary production and thus widen the scope of operations.

Jan 1, 1926

By Walter R. Storms

This paper, which describes the mining methods of the Potash Co. of America in Eddy County, N. Mex., is one of a series being prepared by the Mining Branch, of the Bureau of Mines on mining practices and methods in various mining districts of the United States. 4, T. The mine and plant of Potash Co. of America are situated in sec. 20 S., R.. 30, E.,. N. M. P. M., about 22 miles by paved road northeast of Carlsbad (fig. 1). A spur line of the Atchison, Topeka & Santa Fe Railroad also connects the mine with Carlsbad.

Apr 1, 1948

By Joseph Sofra

It has become increasingly evident that sustainable metals production in the 21" century requires producers to balance the needs of cost effective, high value production with that of responsible plant operation. This is becoming more difficult as lower grade and more complex feed materials, including recycled scrap and residues, arc being processed to reduce production costs and decrease exposure to primary metal market fluctuations. One particular facet of the metals industry facing these challenges in the 21 st century arc copper producers. The recent steady decline in the copper price has seen the industry cut expenditure, tighten control on income streams and focus on high returns on capital investment. For these reasons copper producers arc looking towards flexible technologies that can deliver high value products, with minimal environmental impact at low capital and low sustainable operating costs. Ausmelt's Top Submerged Lancing (TSL) technology for copper production is a low cost, proven technology for the processing of both primary and secondary copper materials. Both the smelting and converting operations introduce significant advantages in environmental performance, improved process efficiencies and high rates of metal recovery. Ausmelt has made significant gains in the past 4 years in establishing a strong market position for its copper technology. New installations in China, South Africa and India as well as existing operations in Zimbabwe and China have demonstrated its effectiveness. This paper reviews the application of Ausmelt Technology for both smelting and converting of primary and secondary sources. It discusses Ausmelt's design and implementation philosophy, and how this philosophy meshes with the needs of the end user.

Jan 1, 2003

By K Fiedler, A Newell, P D. Munro

Test work is the foundation upon which the success of projects and subsequent operations is laid, reflected in Professor Arthur Taggart’s pithy observation: ‘Make your mistakes on the small scale and your profits on the larger scale’. Indeed, Professor AllanTrench has succinctly noted that ‘Get the metallurgical characteristics wrong and you don’t have a project’.With deposits becoming lower grade, more structurally and mineralogically complex, final products requiring lower levels of impurities and tailings management demanding more attention, test work now assumes even greater significance in the acceptance and successful execution of a project. This paper is the first in a series aiming to stimulate thought on the metallurgical test work process by getting back to the fundamental basics through exploring and providing some guidelines for the metallurgical testing world, noting preferred practices as well as precautions and mitigations. This covers the key characteristics of metallurgical test work programs, including what needs to be done, sample selection, quality control and associated drivers, and most importantly, selecting, assessing and managing test work facilities. CITATION:Newell, A, Munro, P D and Fiedler, K, 2018. Metallurgical test work – between a rock and a hard place, in Proceedings 14th AusIMM Mill Operators' Conference 2018, pp 15–32 (The Australasian Institute of Mining and Metallurgy: Melbourne).

Aug 29, 2018

By Renato Affonso de Lima

As colunas utilizadas para a produção de hidrogênio em fornos de reforma a vapor são submetidas a temperaturas da ordem de 900°C. Dessa forma, os aços inoxidáveis austeníticos da classe HPNb se mostram adequados, devido ao endurecimento por precipitação de carbetos de cromo e de nióbio. Sob determinadas condições de serviço, os carbetos de nióbio podem se transformar em um siliceto conhecido como fase G. A interface desta fase com a matriz austenítica é citada na literatura como local preferencial para a nucleação de danos de fluência. Sendo assim a quantificação das fases presentes é importante para a avaliação do acúmulo de danos em serviço. Diante disso, a simulação termodinâmica computacional se mostra uma importante ferramenta, para a previsão das fases presentes. Técnicas como a analise quantitativa das fases presentes por meio de imagens são consolidadas, porém demandam amostras devidamente preparadas e um alto custo de equipamentos na execução destas análises. Isto posto, o objetivo do trabalho é comparar as simulações termodinâmicas computacionais com o resultado obtido por meio de análise quantitativa de imagens geradas por microscópio eletrônico de varredura.

Oct 30, 2017

By B Jones, M Chappell

Permanent rock bolts used to support rock tunnels are required to perform for the design life of the structure as a minimum. Quality of installation is critical to the performance over the life of the rock bolt.This paper will present the findings from an in investigation into the integrity of rock bolts installed in an underground hydroelectric power station cavern and access tunnel. The 25?mm diameter rock bolts were installed 50 years ago, tensioned and post cement grouted. Due to a major machine upgrade the whole facility was subject to an asset survey. The owners are responsible for managing the risks associated with the failure of these rock bolts and ensuring the structural integrity of the tunnels and caverns is maintained to continue operations, protect machinery, assure production and more importantly maintain a safe working environment for all employees and visitors.To help manage risk a proactive approach is desired. To this end a test schedule using a non-destructive testing (NDT) system was carried out by Independent Integrity Testing Pty Ltd (i2t). The system used in this application was RokTel™. The system operates by applying a small axial impact to the rock bolt end and measuring the resultant acceleration response. The rock bolt characteristics affect the acceleration response.The data output from the system is analysed principally using Fourier Analysis (FFT) and sinusoidal waves. The energy generated in the bar, the rate of damping and changes in frequency are all assessed. Testing was carried out on 70 rock bolts within the tunnel and cavern. A selection were then over cored, photographed and documented. The data gathered from the testing is then correlated with physical evidence to establish a calibration for the remainder of the rock bolts and assess if this is a viable method for identifying defective elements, and what degree of accuracy can be achieved. The findings will assist with the future assessment of similar hard rock underground?facilities.CITATION:Jones, B and Chappell, M, 2014. The use of non-destructive testing to identify defective rock bolts – a case study, in Proceedings 15th Australasian Tunnelling Conference 2014 , pp 275–280 (The Australasian Institute of Mining and Metallurgy: Melbourne).

Sep 17, 2014

By Edward L. Beutner, Robert M. Crump

Benson Mines low-grade iron ore reserve is a replacement deposit within the Grenville gneisses of the Adirondacks. The average grade of the crude ore is about 23 per cent iron. The iron minerals are principally magnetite and hematite disseminated throughout the gneisses as discrete grains about 1 mm in size. Both the ores that are beneficiated by magnetic means and the non-magnetic ores that are treated by a gravity method of concentration are found in stratigraphically different positions but are mined from one open pit, which is about 2.5 miles long and 800 feet wide and are treated separately. The gneisses are described and named according to the distinctive mineralogy of each. Recognition of the gneissic types permits the interpretation of the structure as a northward-plunging syncline overturned to the west. A large subsidiary anticline-syncline complex occurs on the east limb of the major syncline. Iron minerals in sufficient quantity to be considered ore are confined to areas where the footwall rock has been overturned to become the hanging wall.

Jan 1, 1968

By E. Gybbon Spilsbury

THE introduction of underground machinery in mines, and especially the invention of the rock drill, called attention to the necessity for some motive power to drive them. The use of steam generators underground is as a general thing inadmissible, owing to the, difficulties of ventilation and the transportation of fuel, and the great loss of power by condensation in the pipes, when surface generators are used, added to the inconvenience of getting rid of the exhaust steam, has precluded the direct use of steam for this class of machinery. Water as a power has with very few exceptions proved a failure, owing to its weight and incompressibility, and there-fore the attention of mining engineers has very naturally turned to the use of compressed air. This agent not only answers all the requirements for power, but has the double advantage of greatly assisting in thoroughly ventilating remote workings, and in cooling the underground atmosphere. It is therefore clear that the successful introduction of underground machinery is dependent on the economical production of good and efficient air-compressing machinery. Although many improvements have of late years been introduced in this class of machines, the most of them are open to serious objections, the chief of which are the very small duty they perform for the power expended, and their great expense, due to the complexity of their construction. This latter fault is the chief reason why the introduction of rock drills and other underground engines is so limited, as comparatively few mines can afford to expend the required capital for the installation of a complete compressing plant. But with the introduction of a cheap and effective compressor, there is no doubt that power drills will become as generally used in mines as the hand drills are now. The great excess of power required in most machines to compress air over that given out again by the use of the air thus compressed (amounting as it does in most cases to sixty per cent.) is well known to all mining engineers. Of course a portion of this loss is due to the friction of the air through the pipes, and will always occur however effective the machine used maybe, but the chief cause -of the

Jan 1, 1880

By F. S. Crawford

This study was made to find methods of preventing back strains, among workers in brick plants, however, the information should apply to other industries that employ hand labor too process materials. The report is based on information in letters from. Bureau of Mines engineers and other safety men in the United States who visited numerous brick plants. Back strains, as wall as hernias and other muscular strains, result when certain body structures are subjected to strains greater than, they can withstand. Such breakdowns may be prevented simply by not straining these body structures. This is simple in theory but complicated in practice. It requires primary education of new workers and reeducation of older workers in the best method of lifting, preemployment physical. examinations to select employees for the jobs that require constant lifting, all possible mechanization of material-handling operations, relocation of machinery, and elevation of working surfaces to reduce to a minimum the muscular effort the workers must exert to perform operations impossible to mechanize. Accidents of any kind are a total bee for the American economy and decrease productivity; whereas mechanization raises the level of productivity and constitutes progress toward total safety. Heavy lifting should be done mechanically whenever possible, saving the men to direct the machines. This is an essential step in preventing strain accidents.

Jan 1, 1953

By D. P. Venter

When Oryx Mine down-scaled in 1994, focus was placed on development, with the primary aim being the exposure and proving of ore reserves. In order to achieve this aim, development ends had to be advanced to reef at the maximum possible rate. This in turn called for support methods which could keep up with the advancing faces, taking up minimum space and time for installation, while providing on the face a real coverage and effective long-term support. In the majority of the development ends which were located in fairly competent ground, the grouted rod development support proved to be adequate until such time as secondary support in the form of meshing and lacing could be installed. The ends developing towards the eastern boundary of the mine, especially in the ?C? block, encountered extremely adverse ground conditions due to the presence of smectite zones within the footwall quartzites. Smectites are a group of montmorillonite clay materials, mainly composed of hydrous aluminosilicates. They occur as minute platy crystals in the rock mass and are especially notable for their ability to absorb liquids. Generally, the zones are found in between the bedding planes of the host rock, and may vary considerably in thickness over short distances. Wherever the smectites were exposed by the development blasting, the rockwalls weathered as the smectites absorbed water and the condition of the tunnel rockwalls deteriorated rapidly. When the smectites were left exposed and allowed to weather, it became almost impossible to install secondary permanent support such as meshing and lacing at a later stage. To minimise the exposure time and subsequent deterioration of the smectite zones, it was recommended that all development ends encountering smectites be shotcreted as soon as possible after blasting. In developing a shotcreting support methodology, both a drycreting and wetcreting system were investigated. The situation at the time ruled out the use of a wetcreting system on the basis of the extensive and costly infrastructure required, as well as its limited manoeuverability. Instead, it was decided to opt for as maller scale but more manoeuverable drycreting system. The system utilized a number of portable drycrete machines with pre-bagged cement, which could support several development ends in close proximity. Initial trials using normal 30 MPa shotcrete on 19level proved successful and the system was implemented.

Jan 1, 1998

By J. A. Saunders, E. L. Rowan

It is now widely accepted that the metal-rich waters found in the oil wells are possible present-day analogues of the mineralising solutions that formed the Mississippi Valley-type (MVT) deposits throughout mid-continental USA and elsewhere. A study characterising the trace-metal content provides additional circumstantial evidence for a genetic link between sediment-hosted mineral deposits and basin brines: Ag, Co, Ni, As and Mo, detected in the scale, are locally present in accessory minerals in MVT deposits and the levels of Ag found in the wells support the conclusion that sedimentary sources for silver should be considered in evaluating the origin of Pb-Zn-Ag deposits in sedimentary terrains

Jun 12, 1905

By Rclssell Gibson, F. S. Turneaure

The tin deposit of Monserrat; Bolivia, consists of one major vein 1600 m in length. The ore is unusual because of the notable quantity of teallite, even though cassiterite is the principal tin mineral. The deposit, formed at shallow depth under a wide range in temperature, may be classed as xenothermal. Polished sections reveal a complex history of replacement, with low-temperature minerals deposited before high-temperature minerals.

Jan 1, 1950

In 1984/85 financial year Australia produced 529 thousand barrels per day (kbd) of crude oil. By far the major contribution (453 kbd) was light waxy oil from offshore Gippsland, Victoria. When these discoveries were made in the latter 1960s, imported oil was available in abundant supply and at low prices. Because of this, the Gippsland producers persuaded Government to control the marketing and pricing of their crude, and thus provide the required security of offtake. Political events in the middle East created supply shortages during the 1970s, and dragged up government selling prices for OPEC crude oil. Thus Arab Light crude that sold for less than US$2/barrel (bl) in 1970 reached $34/bl in 1981. Following the consequent decline in world oil demand, in 1982, Australian refiners sought to evade their obligation to lift Gippsland crude. Hence, in 1983, the Government was forced to introduce a floor quota of 385 kbd of Gippsland crude liftings and to allow producers to export any additional production refiners did not require. On expiry of the old arrangements, Government introduced a partial free market from January 1985, whereby the balance in excess of 350 kbd may be sold to Australian refiners at negotiated prices, or exported as before. In 1984/85 exports were some 90 kbd and will be higher in the current year. About half this total has been exported by BHP, providing valuable experience and lessons which are described in the paper.

Jan 1, 1986