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The paper explains the genesis of the Ballarat College of Advanced Education to its unique position in mining engineering education. A description follows of the development of the Graduate Diploma in Occupational Hazard Management which commenced in 1979 in the cooperative mode of four groups of three weeks full- time study followed by twenty-three weeks in industry. In particular an analysis will be given of the state of origin of students, ages and employing industries. Given the experience from the evolution of this course a similar process is described for the Graduate Diploma in Mining which has been accredited to commence early in 1987.

Jan 1, 1986

Selective open pit mining for gold has been in progress at Harbour Lights since the onset of mining in March 1985. Selective mining techniques used are similar to those in other recently opened gold mines in Western Australia. However certain practices have been introduced to accommodate the irregular distribution of mineralisation and comparatively high mill tonnage throughput. These include selective mining with large bucket excavators, sequential waste stripping - ore mining normal to the strike of the orebody and sample line preparation and ripping on bench floors. Application of these selective mining practices at Harbour Lights enables the operation to maintain delivery of approximately forty by 50-tonne truck loads of ore to the mill crusher everyday, with limited rehandling of material through ore stockpiles.

Jan 1, 1986

Preparing for automated sample preparation has two facets; the need for better procedures as seen by the laboratory Manager and the approach to be adopted as envisaged by the equipment manufacturer. Both have many options and during the 1990s some at least of these options will be tried. As automation of sample preparation is only just beginning, can it be said that there is a real need for better procedures. What does automated sample preparation have to offer? Does it have real advantages or is it just a marketing tool to sell equipment?

Jan 1, 1976

By Best R, Poulos H

This paper discusses the results of an Australian Coal Association Research Program project into the development of a routine analytical design method for roof support in underground mines. Simple design tools have been developed using a combination of elastic solutions, free body diagrams, and pile theory. An approach to the design of roof support in layered strata based on the ability of bolts to resist shear stresses is outlined. It is shown that pre-tensioning and angled installation are effective ways of increasing the effectiveness of bolts in such a situation. In highly stressed strata, macroscopic failure is predicted and a design based on the support of surcharged rock wedges is proposed. The methods are applicable to both coal and metalliferous mines.

Jan 1, 1995

By Dickson T. J

Slag cleaning is an important part of the pyrometallurgical operations at the Kalgoorlie Nickel Smelter. It is a complex system with many streams of different phases and composition. Some of these streams are very difficult to control and/or monitor. Through the use of a statistical computer package, called Minitab, key relationships affecting the economical operation of the slag cleaning process have been found. Data for the statistical analysis was collected from all possible variables around the appendage.

Jan 1, 1991

The characteristics and causes of the spoil pile failures at the Goonyella Mine are described, and research results from investigations of spoil pile instability are discussed. Some effects on spoil stability of the development of deep strip mining projects are considered and recommendations are made for relevant research.

Jan 1, 1981

By Quast K. B

The effects of metal ion addition rates and contact time on the activation of synthetic sphalerite using copper, cadmium and silver ions were determined in order to investigate the exchange characteristics at the mineral surface. The stoichiometry of the adsorption indicated that the activation of sphalerite involved both a simple ion exchange and redox process in which the activating ion and oxygen were reduced, and the mixed-sulphide surface was oxidised to produce elemental sulphur and a metal-deficient sulphide surface. Unactivated sphalerite was shown to be relatively hydrophilic, with recoveries usually less than 20 per cent for a five-minute float. Activated sphalerite could be readily floated without the use of a conventional collector. This inherent flotability of the activated sphalerite had previously been associated with the formation of a metal-deficient sulphide layer; however, this study emphasizses the significance of the surface oxidation processes occurring.

Jan 1, 1993

By G Stephenson, G MacDonald, A Yeomans, S Sinclair, V Knott

Rio Tinto has actively committed to progressive reclamation, concurrent with commercial operations, at its Diavik Diamond Mine. The most significant piece of progressive reclamation undertaken at Diavik to date has been the construction of an engineered thermal rock cover for the mine’s largest waste rock storage area. This 80-metre-tall and 2000-metre-long area is known as the Waste Rock Storage Area – North Country Rock Pile (WRSA-NCRP) and contains the operationally segregated potentially acid-generating waste rock mined over the last 20 years. As part of the mine plan, an opportunity was recognised where a limited 1.5 per cent of the WRSANCRP surface area was required for storage of the balance of life-of-mine generated waste rock and a decision was made to advance the closure design almost a decade ahead of final closure. With over 12 860 000 tonnes of material placed and 57 443 dozer hours logged since cover construction, progressive reclamation on the WRSA-NCRP is scheduled to be complete in mid-2023, three years before planned cessation of commercial operations in 2026. The progressive closure of the WRSA-NCRP demonstrates Rio Tinto’s commitment to not only closure, but modern best practices with integrated mine closure. Over the past seven years, Diavik has overcome multiple implementation hurdles for this project including the psychology of operational standby, the financial mechanisms required to support closure, working within the constraints of a mine plan and the associated operational organisational structures. This paper outlines the lessons learned to provide an example of successful integrated mine planning for closure. The North Country Rock Pile project had three major learnings which resulted in an effective organisational structure that allowed for the execution of an integrated planning model for progressive closure. The initial hurdle the project faced was adapting the psychology of an operational open pit mining team. The team was an experienced mining group who came in with the perspective to target the shortest haul possible resulting in the initial perception that the longer haul of material to the NCRP was an un-necessary task impacting operational performance metrics. After the installation of an improved dispatch tracking system and performance metrics, it was possible to demonstrate that the mine was shovel constrained. This showcased the short haul was generating an increase in queue time not production. With updated performance metrics, the team was aligned to target a decrease standby through haulage to the NCRP. These performance metrics had to be reinforced by financial mechanisms. The operations team was able to offset costs by charging time to the capital project set-up for the closure of the NCRP. This allowed the operations team to receive credit for time that would have otherwise likely been standby. As well, the progressive closure project was able to receive the benefit of not having to incur costs for the drill, blast and load as that was done as part of the operation. This was a significant benefit to the project and one of the primary drivers for the early approvals of the work as the project costs were limited to the incremental haulage distance and placement of the material. Life of Mine Conference 2023 | Brisbane, Australia | 2–4 August 2023 114 While the combined operational and progressive closure approach provided financial advantages, it did result in the project being constrained by the operational activities. A traditional capital project is managed through a linear execution plan where the deliverables within a project are within the realm of control of the project execution team. However, the NCRP project had to be continuously adapted to the outcomes of the pit operations. This included geotechnical constraints, ore delivery, and other operational delays. To adapt, the planning module had to be dynamic but not reactive to allow for adjustments on a shift-by-shift basis. Based on this requirement the Diavik Closure Projects structure adopted a mine planning format. The team executed a similar planning timeline and reporting structure as the mine operations team, allowing planning to be integrated into the operational planning structures on a daily, weekly, monthly and quarterly basis. This resulted in the Projects team as a core pillar of the mine planning team. The process of continuous improvement spanned six years and has resulted in the project being ahead of schedule and under budget for the project’s scheduled progressive closure completion date of June 2023. The North Country Rock Pile project supports the argument that bulk earthworks progressive closure projects should be integrated into the operational mine plan. If the project is aligned the mine plan it allows for dynamic adjustments which capitalise on evolving opportunities inevitable in an operating mine. These cultural and organisational alignments should be supported by appropriate performance metrics and financial mechanisms to ensure united priorities. The result of this alignment provides long-term financial savings for the business as well as delivery of closure objectives.

Aug 2, 2023

Computers are playing an increasing role in the management of technical data in mines. Companies are re-assessing the role of their data processing departments as users demand computer resources in non-accounting areas. Data of all kinds is now being seen as a, company resource, and the role of computing professionals is to help to manage the data flow, not merely to manage computers. The concept of distributed data bases puts the responsibility for data entry, editing and updating with the user. This challenges conservative views of centralized control of computing, suggesting, instead, centralized co-ordination. A survey of the possible applications of computers in technical areas points up the special requirements of handling raw, processed and consolidated technical data. Technical data bases have become flexible as mini- computer hardware and software have rapidly developed. Management has the ultimate responsibility for efficiently administering corporate data bases, and it must ensure suitable policies are developed for this purpose, with enough flexibility to cope with the impact of fast changing technology.

Jan 1, 1980

By Sauer P

The features of Banana screens have been known for some considerable time and recently considerable interest has been generated in the performance of these units. This paper reviews screening principles on Banana and conventional units and demonstrates the capacity and effic- iency of these units. Furthermore, the behaviour of modern Banana screens and modem screens in general, are examined with respect to life, vibration isolation, noise emission and maintenance requirements.

Jan 1, 1978

By Shrivastava P

The iron orebodies of the Pilbara region are formed by supergene enrichment of banded iron formation and rarely do such processes produce orebodies with uniform grade distrib- utions. The orebodies being mined or developed have to be worked to grade/quality constraints imposed by contractual agreement rather than natural characteristics. Hence it is imperative to use a non-biased ore reserve calculation method. The geostatistical study of a typical iron orebody is presented. Emphasised are the geological characteristics of the orebody manifested as a variable grade distribution of iron and impurities; the determination of variogram model; subsequent uses of the model for computation of ore reserves and kriged lock estimates; computation of dispersion variance and conditional simulation of orebody.

Jan 1, 1977

By R. A. Frith, M D. Goodz

Ore-bearing minerals that are located along microfractures are always susceptible to loss during the breakage and sampling of the material. Further losses occur with on-site sample preparation and splitting prior to laboratory analysis. In these cases solid whole rock channel or core samples should be handled with due care to ensure all fines and loose particles are collected and included in the sample for total chemical analysis.Similarly open hole and reverse circulation drill methods are not usable in areas containing old mine workings, heavily fractured ground or highly degraded/oxidised mineral assemblages. Nor are these methods usable to assess a bulk mineable target where the enriched zones were peripheral to or between old mine cavities.

Jan 1, 1993

By Orrock G, McKee DJ

Mathematical models of autogenous and semi-autogenous grinding mills have now reached a stage of development where they can be usefully applied to practical problems. In particular, the models are suitable for inclusion in simulations of grinding circuits to study the effects of cir- cuit changes, variations in ore type and changes in throughput. The paper describes a simulation study of the Elura grinding circuit where the empha- sis was on investigating methods of reducing product size from an autogenous mill-ball mill grinding circuit.

Jan 1, 1988

By Sroka J

A comprehensive feasibility study should be submitted as part of the loan application to a financial institution for debt funding of a proposed project. Its scope should include technical, costing, marketing and other aspects pertinent to the project. The technical presentation should be sufficiently detailed to show that the assumpt- ions concerning future performance are realistic. A lender needs to be convinced that the capital and operating cost estimates are conservatively based with adequate allowances included for contingency and escalation. The marketing assumptions determine the level of revenue from which operating cost, debt servicing, and other commitments are to be met. The foregoing aspects establish the economic viability of the project, and are therefore relevant to the risk assessment and cash flow analysis carried out by a potential lender which determine his ultimate lending Decision

Jan 1, 1978

The Government Mining Engineer of South Africa has decided to legislate that Self Contained Self Rescuers (S.C.S.R.) become a mandatory piece of equipment for all those persons proceeding underground. It is envisaged that: * employees in underground coal mines will be fully equipped with S.C.S.R.s during 1988; * those persons employed in gold mines during 1988/89; and * personnel in all other mines by the end of 1990. It is the intention of this paper to discuss the introduction of these auxiliary life support systems, and to give an update on current market developments.

Jan 1, 1988

By Burnett C. C H

GEMNet, (Grade Estimation using Mapping Networks), is a grade/reserve estimation software system that uses the artificial intelligence technique known as neural networks to perform reserve estimates from both two- and three-dimensional data samples from a mineral deposit. The system is the result of research carried out over the past three years into the feasibility of using neural networks for reserve estimation at the AIMS Research Unit in the Department of Mineral Resources Engineering at the University of Nottingham. This paper describes the architecture of the GEMNet system including details of the neural network components of the system. The performance of the GEMNet system is then compared to several other widely used reserve estimation techniques on two reserve estimation examples. The results produced by the GEMNet system compare favourably with more conventional estimation techniques, but require fewer assumptions to be made about the form of the data used, and do not require the use of complex mathematical modelling.

Jan 1, 1995

Techniques and results achieved during the excavation of the Melbourne Underground Rail Loop (HURL) are summarised and discussed in the context of the various restraints present in a typical urban construction project. Mechanical methods (as distinct from those utilising blasting)accounted for the bulk of the excavation. Ground support was critical in this particular geological excavation setting, but is not discussed in detail except insofar as it constitutes a restraint to excavation progress.

Jan 1, 1978

By Wilson GR

Pellets were produced from carefully sized iron ore and silica sand fractions, under controlled moisture conditions, using a sealed balling drum. The strength of these pellets was measured as a function of moisture content and particle size. The results showed that the strength of the pellets could be adequately described by a model which equates the strength of the pellets with the negative pressure developed within the porous mass, provided that the particle size distribution was narrow and the mean particle size relatively large. However this model failed to account for the observed strengths of pellets produced from systems containing even small quantities of ultrafine particles (

Jan 1, 1972

By D La Rosa, K Caron, H Mamani, W Valery, R Diaz

The Gold Fields Cerro Corona copper-gold deposit in Peru has heterogeneous rock characteristics in terms of its mineralogical, geological and geotechnical properties. Blast design variations in these conditions directly impact the run-of-mine (ROM) fragmentation, which in turn influences downstream process efficiencies. In particular, when harder ore is processed, throughput and circuit performance may be limited.To evaluate the potential to increase throughput and improve overall plant performance by optimising blasting practices and comminution circuit operation, Gold Fields La Cima engaged Metso Process Technology and Innovation (PTI) to conduct a full process integration and optimisation project at Cerro Corona. Blasting, crushing and grinding processes were reviewed to identify the potential to achieve substantial improvements in productivity when treating the most competent ore types.Site-specific models of the blasting, crushing and milling processes were developed using SmartTagTM ore tracking technology for calibration and validation. Ore tracking permitted locations in the blast volume to be queried against the geotechnical block model to determine the hardness and structural parameters of the feed to the comminution circuit. They also ensured surveys were conducted when ore from the audit blast was flowing through the crushing and grinding circuits.The predictive models developed enabled PTI to demonstrate how changes in blast design influenced both ROM fragmentation and the performance of downstream comminution processes. Outcomes of the project suggested changes to blast designs and comminution practices, and these were partially implemented for a validation trial. The trial demonstrated a 14.8 per cent increase in mill throughput for the specific ore selected for the study, and an average increase of 5.7 per cent for all ore types. There is potential to further increase throughput and process performance if all recommendations are implemented. This paper describes the methodology used and benefits to the operation from the mine to plant.CITATION:La Rosa, D, Caron, K, Valery, W, Diaz, R and Mamani, H, 2015. Blast fragmentation impacts on downstream processing at Goldfields Cerro Corona, in Proceedings 11th International Symposium on Rock Fragmentation by Blasting, pp 333–342 (The Australasian Institute of Mining and Metallurgy: Melbourne).

Aug 24, 2015

By Gadsden R. W

Physical and chemical requirements are defined for coke and ferrous materials used in modern high productivity blast furnaces operating in Australian conditions. Recent developments in the type of equipment required to be installed at the steelworks to ensure these requirements are described with illustrations from current plant practice provided.

Jan 1, 1976