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By R E. Conder

A major initial and ongoing cost component in many mining operations is that of transporting mined materials and processed ore from the point of extraction or processing to the next operation. For various reasons the transport distance can be significant or in some cases the route may be particularly challenging. The trend to higher production rates to gain economy of scale benefits and capitalise on sales opportunities means that optimisation of transport can play a significant part in profitability. Apart from the cost criteria, increasingly there are other criteria such as environmental restraints, land ownership and security of supply that can have a significant impact on determination of the optimum route and transport vehicle. The paper aims to briefly highlight the important selection criteria and the benefits and disadvantages of the most commonly utilised transport vehicles. It then moves on to looking in more depth at belt conveying, highlighting the unique capabilities of the Metso MRC Cable Belt Conveyor system.

Jan 1, 2004

The paper outlines the philosophies and the methods applied to resource estimation by North Flinders Mines Limited at The Granites. These are based on recognition of the prime importance of quality data, accurate geological perception of the deposit, and the judgement of the estimator. With reference to one particular deposit, East Bullakitchie, the series of resources statements published over a 5 year period is compared with the corresponding history of discovery and development. The comparison Illustrates:

Jan 1, 1990

With the proclamation of the Environmental Protection Act, 1971-80, the Environmental Protection Authority and Department of Conser- vation and Environment were established to enhance the quality of the environment. Proposed gold developments of all scales can be referred to the Authority in the form of a Notice of Intent. Environmentally significant projects might then require preparation of an Environmental Review and Management Programme. Current environmental issues include the'effects of clearing by prospectors,, mine dewatering and tailings disposal. INTRODUCTION In the past, the environmental aspects of gold industry related activities have received little attention. However, with the proclamation of the Environmental Protection Act, 1971-80, mechanisms were instituted which allowed both for referral of projects to the Environmental Protection Authority (EPA) and establishment of the Department of Conservation and Environment. As well as providing assistance to the EPA on referred projects, the Department is concerned about a number of environmental issues associated with the gold mining industry.

Jan 1, 1982

The Hodgkinson goldfield contains over 50 separate lodes which have produced 9.7 tonnes of gold from ore averaging 37 g/t. The gold-quartz.lodes are spatially separate from tin and base metal mineralisation, associated with Permo-Carboniferous granitoids in the province. Host rocks consist of sub-greenschist metamorphic grade shale, conglomerate, sandstone, spilite, chert and melange. Oreshoots average 100 x 30 x I m in Size and are contained in cross-cutting quartz. filled with steep-dipping shear zones. Mineralisation in the quartz. consists of gold with minor arsenopyrite, pyrite, galena, and sphalerite with rare calcite. Scheelite and stibnite are aSSOCIated locally but are not necessary proximal or coeval. Alteration is restricted to centimetre-scale phyllic selvedges adjacent to the veins and veinlets.Most of the lodes and vems occur within six main 1.5 x 0.25 km mineralised areas whIch may indIcate separate areas of fluid flow and precipitation. Ore controls differ m melange- and sandstone-hosted lodes but several features are common to all the oreshOOlS. Most of the lodes occur within zones of duauon that are caused by splaymg, refraction through carbonaceous shale-sandstone contacts, or by rolls and changes in strike and dip.Lithologic contacts may act as areas of permeability and chemistry contrast which focus fluid and precipitation. Tensional veins are common between parallel shear zones and curved spur veins occur both in the hangingwall and footwall of the main fissure. Intersections and contacts may have enhanced local fluid flow in many of the areas.

Jan 1, 1991

One of the most praninent Bouguer anomaly features in the Broken Hill District is the long wavelength high of 10-15 ngals above background which forms a northeast trending, oval zone sane 15 km by 45 km with Broken Hill on its northern gradient. Rock density measurements and modelling indicate that this anomaly can be explained by the presence of generally relatively higher density meta- sediments extending from the surface to a depth of about 2000 m. The regional Bouguer anomaly data show that the Willyama Block and Euriowie Block are mostly overlain by a fairly smooth Bouguer anomaly high in the range 5-15 mgals, whilst the surrounding younger sediment covered areas, including the Mundi Mundi Plain, Murray Basin fringe and Bancannia Trough, are mostly overlain by lows which range to minus 30 mgals. Thus in terms of the gravity pattern the Willyama and Euriowie Blocks form a fairly continuous and haogeneous entity. However, the 5-10 mgals relative low over part of the Torrowangee Synclinorial Zone indicates that the Adelaidean System metasediments are in aggregate slightly less dense than the Willyama Supergroup metasediments. The low can be modelled to indicate a basement link between the Broken Hill and Euriowie Blocks at 1000-2000 m depth.

Jan 1, 1983

Australia had an active uranium mining industry in the 1950s with uranium oxide being supplied under contract to the atomic energy authorities of the U.K. and U.S.A. In the 1960s, when these con- tracts concluded, domestic production ceased, apart from Rum Jungle, whose production until 1971 was stockpiled. By the 1970s, the demand for uranium from the electrical utility industry had risen sharply and the effects on Australia were notable. The Mary Kath- leen mine re-opened in 1976 but, more significantly, exploration activity suddenly expanded with the re- sult that several world-standard deposits were locat- ed. Western world requirements for uranium based on increasing energy consumption and a changing energy mix, will warrant the development of Aust- ralia's resources. By 1985 our mines could be pro- ducing 9,500 tonnes of uranium oxide yearly and by 1995 the export value from uranium could reach that from wool. In terms of benefit to the community the economic rewards are considerable but, in terms of providing energy to the world, Australia's uranium is vital.

Jan 1, 1978

By J F. C L Costa, J C. Koppe

The goal of this study is to characterise co-processed clinkers by identifying the most common minor elements, their distribution in the clinkers and possible effects on the mineralogical properties of the same. The results show the presence of an elevated content of transition metals, especially manganese concentrated in the matrix (up to three per cent) of the clinkers. Anomalous concentrations of arsenic have also been detected, especially at silicate crystal edges. The results indicate that the tracer elements can perfectly be associated to the mineralogical characteristics of the clinkers.

Jan 1, 2008

By Kupper T

Firstly, electric analog models are discus- sed to show fluid streaming conditions. In these models the depth of blast at tuyere level, the height of the bath, the influ- ence of different angles of the furnace zones and the different possibilities of the root of the cohesive zone have been changed. Tests to define the influence at a large blast furnace are given. Secondly, the wear of carbon bricks in the hearth is examined under the influence of gas, slag and pig iron. Oxidation tests in a special scanning microscope with the pos- sibility of heating and gas treatment are shown. Wear mechanisms are discussed fora large blast furnace and proposals for im- provement are given. Finally, the possib- ilities and value of the temperature meas- urement in the hearth block are discussed.

Jan 1, 1981

By B Taylor

Although the underground mining environment is arguably safer now than at any time in history, as underground mining operations across the globe increase in-depth, magnitude, and complexity, protecting workers from harm becomes increasingly challenging. In deep, stressed, seismic mines the development face is one of the most hazardous work areas. The active face is usually the furthest extent of the underground workings, so ventilation can be difficult to maintain, exposing workers to high temperature and humidity while working on foot and doing manual labour. While mechanisation has made many tasks easier in modern times, the reality of underground mining is that development charge-up workers still spend long periods directly exposed hazards at the face. In 2019, Orica and Epiroc partnered to co-develop the world’s first fully mechanised development charging unit using fully wireless initiation, called Avatel™. Built on Epiroc’s M2 Boomer carrier platform, the system is designed to allow one person to charge a development face from the safety of a fully enclosed cabin, thereby reducing exposure to hazards at the face. The system was prototyped in Europe before entering commercial introduction in 2022. This paper reviews earlier attempts to mechanise underground charge-up and describes the development journey and engineering challenges of building a mechanised development charging machine.

Mar 29, 2023

By Jankowski P

The Bannockburn gold deposit is located 67 km north-west of Leonora in a poorly exposed part of the Norseman-Wiluna belt of Western Australia. The deposit consists of narrow, complexly shaped orebodies which have presented a challenge to find successful grade control and mining methods. The deposit also presents an opportunity to examine in detail the geology of this part of the Norseman-Wiluna belt.This paper discusses the geology and structure of the Bannockburn gold deposit as well as the grade control and mining systems developed to define the ore and extract it with minimum dilution. We discuss the different techniques employed for grade control in the past and their shortcomings, and the evolution of the present system of doing grade control in cross section from blast hole assays.

Jan 1, 1993

By S M. Arndt, D Tyler, F Reusch

Although significant advances have been made in understanding the mechanics of pit slopes, numerical modelling hasnÆt significantly impacted on the reliability of the design process. It is well known that legacy modelling approaches donÆt simulate large slopes well. In recent times, the emergence of very large finite element (FE) models with more than ten million degrees of freedom and the ability to simulate a large number of discrete structures, has allowed a step change in the simulation precision for slopes. The model size allows global and local effects to be realistically simulated in one model for the first time and the process can be better integrated into normal open pit slope engineering processes. Some examples of simulation of very large open pits are shown that demonstrate the challenges and some recent advances in modelling large slope behaviour. Significant limitations in the current measurement and observation regimes of open pits have been identified.

Jan 1, 2007

By E Rubio, N Morales

Currently, mine plans are optimised by using several criteria as objective functions, like profit, life-of-mine, concentration of some pollutants, mining costs, confidence level or ore resources, with consideration of constraints related to production rates, plant capacities and grades. Whilst this approach is successful in terms of producing high value production schedules, it uses a static opening sequence of the drawpoints and therefore the optimisation is made within the level of freedom left by the original opening schedule, and as a result it is far from the true optimal value of the project. This paper presents a model to optimise the sequence of drawpoint opening over a given time horizon. The emphasis is in the precedence constraints that are required to produce meaningful operational sequences considering the exploitation method (panel or block caving), physics considerations and logical rules. Further on, while it applies the standard approach of maximising net present value (NPV), it considers other targets for optimisation, like the robustness and constructability of the plans. Finally, it applies the model to real data to obtain feasible plans by means of this model. The first tests were done varying the production capacity of the mine.

Sep 26, 2011

By S Khadhraoui, T Yusuf, C Kirmse, E Hecker, R Degel, A Akouch, N Borowski, M Reuter

For an optimal design and control of metallurgical processes, a deep understanding of the thermodynamics of the governing reactions is required. Modelling the thermochemical behaviour of those reactions is complex, as it involves multi-component and multi-phase systems. For this purpose, thermodynamic computing systems such as FactSage™ (Bale et al, 2016), which combine Gibbs energy minimisation routines with large databases of optimised thermodynamic data of solutions and compounds, have been used within the SMS group GmbH. Recently, the successful integration of those thermodynamic computing systems into the digital platforms of SMS has been achieved through ChemApp, which made running complex thermochemical calculations in Python-integrated development environments possible. ChemApp is a programmer’s package for thermochemistry and incorporates the Gibbs energy minimiser of FactSage™ as reported by Petersen and Hack (2007) as well as by Zietsman and Petersen (2018). The digital platforms link the fundamental and the industrial aspects together and can be applied as a process advisor, or for the evaluation of the environmental footprint and the economic implications of different process routes, as discussed by Reuter (2023). Two examples illustrating the progress of the developments in this regard will be introduced: 1. The Tilting Refining Furnace (TRF) for copper scrap recycling and refining to anode copper (the BlueControlApp). 2. Dephosphorisation control for the oxygen steelmaking process (Basic Oxygen Furnace (BOF)).

Jun 19, 2024

By R J. Butcher

Many deposits have been evaluated as potential block caves over the last 20 years due to the perceived benefit of low operating costs. However, block cave projects are typically capital intensive, with mass mining providing high throughput rates that required large investments in mining, processing and utilities infrastructure. While the key economic metrics in deciding to proceed with a caving project are typically net present value (NPV) or internal rate of return, these may not represent the best decision metrics for some companies. Where a caving project is competing for scarce capital amongst other projects in a company’s portfolio or where the caving project is the only project being evaluated by a company trying to raise capital, other metrics may be more appropriate. This paper explores the use of present value ratio and the minimising of maximum negative cash flow as suitable metrics in determining alternative strategies. Trade-offs between optimising for economic value and capital efficiency measures allow for decision-makers to evaluate potentially higher-risk, higher-capital and maximum NPV projects against lower-risk, lower-capital projects.CITATION:Stewart, C A and Butcher, R J, 2016. Block cave evaluation, in Proceedings Seventh International Conference and Exhibition on Mass Mining (MassMin 2016), pp 809–816 (The Australasian Institute of Mining and Metallurgy: Melbourne).

May 9, 2016

By Nye P. B, Fisher N. H

At the second Empire Mining and Metallurgical Congress held in 1927, the Empire Council of Mining and Metallurgical Institutions was formed and it was proposed that the Council take steps to prepare a "Review of the Mineral Resources and Industries of the Empire." At the third congress in 1930, it was resolved that the proposal to institute the review should be submitted to the Imperial Conference held in 1930. This was done, and the Minerals Committee, of the Imperial Economic Committee compiled, an interimreport which was based on statistics of imports and exports, and did not consider resources and consumption.In 1942 the Institution of Mining and Metallurgy, London, wrote to the Empire Council and stated that it was desirable that the Council should be in a position to take part in decisions affecting the future of the mining and metallurgical industries. The Council communicated with the constituent Institutions regarding the nominations of two members then in England. Subsequently the Mining, Geological and Metallurgical ,Institute of India prepared a review of the mineral resources and industries of India and their post-war development, and the Empire Council forwarded a copy to the Australasian Institute of Mining and Metallurgy and asked if that Institute would submit a review on simjIar lines for Australia. The Australasian Institute arranged that the Australian review should be prepared by...

Jan 1, 1946

One of the great attractions of academic life, for those who enjoy the opportunities of university teaching, is the continual contact with some of the most able young minds which each rising generation produces. So when I was asked to give a paper at t

Jan 1, 1994

By Rosentreter N

Difficulties with froth flotation recovery and vacuum de- watering equipment for the treatment of fine coal have been investigated. Mechanical alterations to cyclone desliming banks, and flotation cells are described. A large disc filter has been replaced by two drum filters for dewatering, and the improvement in plant. operation is discussed:

Jan 1, 1978

By Y Li, B Shen, S Zhang

Jointed rock mass is often encountered in rock engineering and its stability has always been a major concern in underground engineering. To analyze the stress characteristics and their variations in jointed rocks, in this study, a new concept of sub-instability stage before rock failure is defined, and a new experimental method is used to investigate interaction between defects and intact rock of the jointed rock mass during the subinstability stage., Firstly, external characteristics of stress and failure mode of the whole jointed rock are investigated systematically by conducting uniaxial compression tests on red sandstone samples with a set of preexisting open flaws of different sizes, and the interactive damage of intact parts and defects in the subinstability stage was further studied. Secondly, rock-like material samples made of bonded plaster blocks were tested and internal data from stress sensor between the strong and weak segments were collected. The transforming processes from independent activity of the individual segment to overall interactive movement of jointed rock before the unstable failure were analysed. The test results indicated that the subinstability stage marked the beginning of interactive failure between the intact rock and defects. In the early subinstability stage, the relatively intact parts bore most of the load in a jointed rock mass, and the defects were damaged firstly which caused high strain around it. The areas of high strain increase rapidly, extending and migrating, causing damage to the intact parts. In the later sub-instability stage, the interaction effect reached its maximum, and a large number of cracks appeared in the intact rock and they propagated and coalesced. Intact parts experienced rapid failure and then the jointed rock failed. The experimental method used in this paper to identify the sub-instability stage could be used to identify failure precursors of jointed rock masses and to develop technology for disaster prevention in rock engineering. CITATION:Zhang, S, Shen, B and Li, Y, 2018. Experimental studies on interactive failure characteristics of jointed rock, in Proceedings The Fourth Australasian Ground Control in Mining Conference (AusRock), pp 453–461 (The Australasian Institute of Mining and Metallurgy: Melbourne).

Nov 30, 2018

By Turner W. G, Trundle R. S, Medland D. G

Contracting has evolved from basically a tradesman providing a service for an `employer' to a multi disciplined organisation providing an all compassing service for a client.Having commenced its activities as Thiess Bros Pty Ltd, providing simple earthmoving services in rural Queensland, Thiess Contractors Pty Ltd which provides a wide range of services for Governments and Industry is used as an example of an experienced multi-disciplined Contractor.

Jan 1, 1992

Natural Gas has been available in New Zealand for twenty years. During that time the gas share of the energy market has grown and now natural gas forms a significant part of New Zealand's energy scene, helping consumers to achieve a higher standard of living, and reducing dependence upon imported oil.Natural gas is now used for petrochemical manufacture and power generation in addition to direct supply to consumers.As concern for the environment continues to build, natural gas will have an increasingly important role to fill in these markets. This paper sets out the background to the development of natural gas in New Zealand and identifies the current markets. It then looks at those matters which are likely to influence the role of natural gas in the 1990s.

Jan 1, 1990