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By F Mwijage

"The benefits of measuring blast movement to reduce ore loss and dilution have been recognised by many people for many years and various methods have been used with limited success. Geita Gold Mine is running the pilot study on the blast movement monitoring (BMM) system which is a revolutionary method developed and patented by the University of Queensland and Blast Movement Technology (BMT). The system consists of directional transmitters placed within the shot prior to blasting, which are then located after the blast with a special detector and then the data is processed with purpose-designed software.As part of continuous improvement on grade control, Geita Gold Mine is running a research project in all operating pits with the objective of: quantifying the three-dimensional blast muck pile movement and finally utilise the movement data to define post-blast ore polygons and incorporate the movement dynamics during block modelling,quantify the potential savings for ore loss and dilution,improve mine geologists knowledge of blast dynamics, andstimulate greater co-operation between drill and blast engineers and geologists to achieve optimum blast designs.To any operation with selective mining, it is critical to the economics of an operation to control ore loss and dilution; getting it wrong will result in significant lost revenue. Implementation of ongoing pilot study on electronic balls as determinant on blast movement dynamics on ore would be of longer term solution and big investment pay back.CITATION:Mwijage, F, 2012. Pilot study on blast movement monitoring at Geita gold mine, in Proceedings Narrow Vein Mining 2012 , pp 49-58 (The Australasian Institute of Mining and Metallurgy: Melbourne)."

Mar 26, 2012

A new bench blast design method and its realization with the assistance of the computer is introduced. The basic design principle is to define a rhomb cell, called fully- fractured zone, through a series of full scale bench crater tests and apply this geometric pattern in multi-hole, multi- row blast design. To illustrate the design method, the optimization process and assessment of blast performance are presented in the context of a case study.

Jan 1, 1992

By K Zic, P Pickering, P Fraser

Water is a defining feature of the Pilbara. Its management was and remains vital for the pastoral industry which European settlers established when they first came to the Pilbara, and for the mining industry which now dominates economic activity in the Pilbara. Water availability in the Pilbara is, however, problematic. Severe droughts and major floods can occur at close intervals. In response to this uncertainty, the Department of Water undertook a Prefeasibility Study to determine, at a high level, the water requirements and opportunities in the Pilbara region. This paper reports on the outcomes of this study and the water integration opportunities in the region, identifying the sources of water supply and offers possible options for managing this water sustainably for the present and future demand. A range of supply opportunities is reviewed including: dewatering from mining operations, surface water, and desalination. All opportunities were subject to order of magnitude costing, including capital, whole of life and retail unit pricing with preferred options receiving further interrogation through triple bottom line (TBL) analysis to prioritise solutions. Options were also subject to intangible quantification (IQ) including benefits from the reduction of carbon emissions to ensure that the preferred option is based on factors other than just the least cost. Demand analysis was undertaken to identify current and future requirements and were assessed through review and integration of regional and sub regional master plans and consultation with mining, agriculture, industry and the community. The paper concludes that the viability of a Pilbara integrated water supply scheme depends on the development of a financial mechanism involving both government and industry participation models. The agreed scheme formed the basis of a submission to Infrastructure Australia for funding assistance.

Jan 1, 2009

By K L. Silversides

Shales form distinctive peaks in natural gamma downhole logs, which are used to manually identify the location of ore boundaries. These shales form important lithology markers that can potentially be automatically identified using Gaussian processes. This approach is trialled using data from a typical iron ore mine in Western Australia which contains the Marra Mamba sequence of the Hamersley province.The method uses Gaussian processes (GPs) with a single length scale squared exponential covariance function. A library of 8 m sections, where natural gamma measurements were taken at 10 cm intervals down the hole, was used to train the GP model. This library was iteratively improved and was tested using natural gamma logs that were not included in the library. Areas that were misclassified or were not clearly classifi ed were added to the library. The new library was then used to train the model and improve the results. The trials used a double gamma peak from the NS3 and NS4 shales at the boundary between the Newman 1 and Newman 2 ore zonesin the Newman member and the AS1 and AS2 shales at the base of the West Angelas member. The results show that both boundaries can be identifi ed with an accuracy of over 99 per cent. The classification has the highest accuracy on undeformed shales. This method provides a fast, accurate and objective identifi cation of shale and ore boundaries and can potentially replace the current manual detection.

Jul 11, 2011

By Jensen B

The approach of using the Coward Triangle for the analysis of flammable mine gas mixtures has been examined for its application, to the flammability of coal dust/gas/air mixtures. Explosible lean limit and rich limit concentration data for dust/methane/air mixtures are examined and illustrated using co-ordinate geometry. It is concluded that a three-dimensional envelope representing hybrid explosible mixtures can be drawn. The dimensions of this explosive zone will vary with the characteristics of the coal dust and the gaseous composition of the mine atmosphere. Further research is needed to establish these dimensions for important mined seams.

Jan 1, 1994

By Sun Y. L, Jiang J. J, Lu S. L

A distinguishing feature of tunnels in squeezing rocks is that a large deformation of the surrounding rocks takes place slowly and gradually, often called squeezing phenomenon. It is different from the rocksbursting phenomenon during which the deformation of tunnels occurs instantaneously when the resulting stresses exceed the strength of the surrounding rocks. The squeezing phenomenon has received great attention in the field of rock mechanics and tunnelling recently. The mechanism and various factors related to the large deformation and failure of tunnels in squeezing rocks are discussed in this paper on the basis of field investigations and laboratory model tests. The relationship between the deformation of surrounding rocks and support of the tunnels in squeezing rocks is presented in the form of numerical modelling.

Jan 1, 1995

The published safety policy of Mount Isa Mines Limited, together with details of the organisation and control techniques adopted by management to pursue an active safety programme within the company, is presented. The importance of communication by management through the organisational hierarchy and procedures instituted to ensure rapid and concise feedback on safety concerns are detailed. The paper also describes the role of the occupational health department and safety committees in assisting management to monitor the safety effort of supervisors and employees. Current safety performance levels are tabled together with details of some aspects of the programme on which safety effort will be concentrated in the future.

Jan 1, 1975

The Central West of New South Wales is emerging as a significant metallogenic province. The development of Northparkes Mines (North Limited) and the Cadia Hill deposit (Newcrest) are establishing NSW as a highly prospective porphyry copper-gold province. Exploration in the area has been further buoyed by the Ridgeway discovery by Newcrest near Cadia. The fact that the Ridgeway prospect was discovered 300 m below surface under Tertiary basalt cover indicates that surface prospecting can no longer be considered alone as an adequate method to find significant new deposits.

Jan 1, 1997

By J Player, K Braddon

High productivity mining is the key to the financial success and stability of modern mines. This can be achieved through the use of new technologies, the development of innovative work practices andoptimisation of the mining method to suit the mining environment.Big Bell Mine is a 1.7 Mtpa longitudinal sublevel caving operation at a head grade of 3.14 g/t. Annual production is 170 000 ounces of gold. The selection and implementation of bulk emulsion explosives was seen as the logical progression from blow loaded ANFO for the high tonnage rate required from the longitudinal sublevel cave.Prior to the implementation of bulk emulsions an investigation wasrequired to examine the technical and financial benefits available with the introduction of bulk emulsion. This paper examines the review process and the successful implementation of bulk emulsion explosives at Big Bell.

Jan 1, 1999

By Woodlands W. K

A 3D graphics modelling system has been applied to longhole stope ring design at Z.C. Mines, Broken Hill, NSW. This has been in operation for a four month period (January, 1988). The purpose of this application was to provide computer assistance to mine planning engineers and blasthole design draftsmen for the longhole design process, particularly by: 1. reducing the- volume of tracing, drafting and geometric manipulation which is a significant feature of the manual design process, 2. providing additional design drawings to enhance the conception and implementation of stoping design.

Jan 1, 1988

By J Bohm, B Csoke, I Tarjan

In process technology, especially in coal preparation, it is often necessary to have a continuous knowledge of the average density of granular material in order to achieve both quality control and process control. The paper presents a new method and means supported by laboratory measurements for the rapid, practically continuous, determination of the average density of continuously supplied granular material through frequent sampling.

Jan 1, 1993

By M Balamurali

In mining, grade control generally focuses on blasthole sampling and the estimation of ore control block models with little or no attention given to how the materials are being excavated from the ground. In the process of loading trucks, the underlying variability of the individual bucket load will determine the variability of truck payload. Hence, accurate material movement demands a good knowledge of the excavation process and the buckets’ interaction with the environment. However, equipment frequently goes into off-nominal states due to unexpected delays, disturbances or faults. The large amount of such disturbances causes information loss that reduces the statistical power and biases estimates, leading to increased uncertainty in the production. A reliable method that inferences the missing knowledge about the interaction between the machine and the environment from the available data sources, is vital to accurately model the material movement. In this study, a twostep method was implemented that performed unsupervised clustering and then predicted the missing information. The first method is Density-based spatial clustering of applications with noise (DBSCAN) based spatial clustering which divides the diggers’ and buckets’ positional data into connected loading segments. Clear patterns of segmented bucket dig positions were observed. The second model utilised Gaussian process regression which was trained with the clustered data and the model was then used to infer the mean locations of the test clusters. Bucket dig locations were then simulated at the inferred mean locations for different durations and compared against the known bucket dig locations. This method was tested at an open pit mine in the Pilbara region of Western Australia. The experimental results demonstrate the advantage of the proposed method in inferencing the missing information of bucket-environment interactions and therefore enables miners to continuously track the material movement.

Jun 22, 2022

By Scott A

The object of most blasting operations is to destroy the insitu structure of the rock mass so that mechanical equipment can efficiently excavate the rock fragments. In achieving this objective the blasting engineer is also concerned with minimising damage to the adjacent rock which forms the mine structure relied upon to provide support. Damage to this "structural" rock is undesirable but usually occurs as a result of two distinct processes: ò readjustment of stresses around the excavation as a result of the mining process itself ò impact of vibration and high pressure gases from blasting operations. Gross damage to mine structures from either cause is observed as visible alteration to the appearance of the rock structure in the form of cracking, slabbing, back or over break and visible displacement. Recent work at the Julius Kruttschnitt Mineral Research Centre (JKMRC) has shown that significant reduction in the strength of a rock mass can take place well before the onset of these obvious signs of damage. It has been demonstrated that the effect of blast damage on the behaviour of the rock mass can be many times more prominent than the effect of stress redistribution. This offers the blast design engineer the opportunity to significantly reduce blast induced damage to rock structure by modifying blasting practices. This paper introduces the current JKMRC postgraduate research projects investigating the evaluation and control of blast damage.

Jan 1, 1990

It is not often that mines have as much warning of the approach of bad ground conditions as was the case at the Western Mining Corporation, Kambalda Nickel Operations Lafranchi/Schmitz Decline. Most aspects of this operation are in fact quite unique and like the best solutions, the answer to the problem of weak and foliated ground conditions was relatively simple; requiring the use of readily available explosives although the idea of using it in this manner may not be the most obvious.The use of high shock energy POWERGEL 2131 cartridges proved to be the correct answer, in conjunction with small changes in drill pattern design. The resulting lack of overbreak bears testimony to the success of the concept and the commitment of the miners to achieving a safe working environment.

Jan 1, 1992

By V Salamakha, K Tang, G Si, J Oh, X Wu, Z Yu

The development of machine learning (ML) algorithms has led to promising advances in lithology classification from geophysical logs, which is indispensable in various underground engineering applications. Due to the resolution and availability of logging data, ML models can recognise lithology change in a definitive form at a fine scale (0.01 m). While the results from previous models indicated promising performance in the classification, the robust capability of generalising lithology prediction to unseen data may not be true for those models due to: (1) data bias caused by borehole selections, and (2) logging data mismatches among boreholes. To this end, this paper aims to investigate the generalisability of ML models and seek potential improvements. Four ML models were selected to be trained on single reference boreholes to test the other (as unseen) in the same region, which includes Support Vector Classifier (SVC), Random Forest (RF), eXtreme Gradient Boosting (XGBoost) and Residual Neural Network (ResNet10). The data set involves 11 boreholes from a coalmine in north-western Bowen Basin (Queensland, Australia): density, gamma ray, neutron, and sonic logs are selected as inputs. Additionally, a data adaptation method is applied for better generalisability. The results show that there is an accuracy trade-off between the same borehole and unseen boreholes across the models. It also indicates a 16–43 per cent reduction in model performance when generalising the predictions (in marco-F1 score), while the adapted data sets can contribute to a around 12 per cent improvement. This study provides a fundamental understanding of the model generalisability when using a single borehole, essential for further correlating boreholes for regional lithology classification; the adaptation method can improve the generalised accuracy, and reduces the labour to label lithology, which facilitates the identification of gas storage mechanisms, geological/geophysical modelling, and stratigraphic analysis.

Sep 1, 2024

By Andrews JRG

Chrysotile asbestos is a valuable resource. Used as a reinforcement in asbestos cement, products are obtained which are cheap, are not attacked by vermin, do not rot or support growth of fungi and are unaffected by water or humid conditions. Such products are of great value in the developing countries where inexpensive and durable building materials and pressure pipe are very important to development, housing and water supplies. Concern over the adverse effects of inhaling asbestos has led to the introduction of increasingly stringent controls world wide on the quantities of airborne asbestos per- missible in the occupational situation. Wet processing has the potential for virtually eliminating the environmental concerns with asbestos dust both in fibre production and in the materials handling section of the manufac- ture of asbestos cement products. In addition, high efficiencies associated with wet process- ing mean that better yields are obtained and that the tailings which are dumped have a lower residual asbestos content. Since early 1977, ICI Australia and Woodsreef Mines have been engaged in a programme of research to develop and evaluate a wet mill- ingprocess to produce, from ore and existing tailings, high grade fibre suitable for use in asbestos cement products. The process has been developed through microscopic studies, labora- tory bench scale experiments, work in a small scale semi-continuous plant and product evalua- tion on experimental size Hatschek asbestos cement machines. A prototype mill with a normal feed rate of 1z tonnes per hour and capable of producing pipe grade asbestos from Woodsreef ore has been constructed and was operational from January, 1982 to July, 1983. A range of asbestos cement products have been made successfully on full scale Hatschek machines using fibre from ore and tailings milled in the prototype mill. Economic evaluations indicate that a wet process mill would be cheaper to build, operate and maintain than an equivalent dry process plant. A commercial plant has been designed 1. Manager New Process Development, Woodsreef Mines Limited, Barraba, Australia. 2. Senior Lecturer, Department of Chemical Engineering, Monash University, Vic, Australia. formerly Senior Research Officer, Research Department, ICI Australia Limited

Jan 1, 1986

By R Dimitrakopoulos

The development of mineral resources is based on a spatial model of the orebody that is only partly known from exploration drilling and associated geological interpretations. As a result, orebody models generated from the available information are uncertain and may require the use of stochastic conditional simulation techniques. Multiple-point methods have been developed for petroleum reservoir modelling, enabling reproduction of complex geological geometries. This paper considers a multiple-point approach to capture the uncertainty of the lithological model. The implementation of the method at the Yandi channel iron ore deposit in Western Australia and performance characteristics are discussed. The uncertain lithological model translates into considerable grade-tonnage uncertainty.

Jan 1, 2007

By D Dickson

The properties along Ida Avenue in Mosman stand 10 m above the road on an outcrop of Sydney sandstone. Access to the houses is generally via a long steep staircase. The owner of 22 Ida Avenue identified an opportunity to use the natural strength of the rock beneath his property to excavate an underground garage and to provide access to the basement of his property via a 10 m elevator shaft from the back of the garage. This paper will describe the design and construction of this unique and innovative urban development.

Jan 1, 2008

INDEX OF CONTENTSIntroductionChemical compositionsNormally Cooled MattesPort Kembla mattesMount Lyell matteMount Morgan matteGranulated MattesConclusionsIllustrationsINTRODUCTIONIn a previous paper in these Proceedings(l) an account was given of the composition of some copper-lead mattes from the Port Pirie Smelters. The research programme of the Mineragraphic Section of the Commonwealth Scientific and Industrial Research organization has since been extended to copper-iron mattes from Port Kembla (The Electrolytic Refining ana Smelting Co. of Australia), Mount Lyell (The Mount Lyell Mining and Railway Co.) and Mouilt Morgan (Mount Morga:p. Ltd.).Chemical Composition of the Mattes.The mattes examined have a considerable range in chemical composition, as is shown by their analyses (Table 1).

Jan 1, 1949

The use of the heavy media cyclone (HMC) Separation process for the treatment of ores in a particular size range is comparatively new to Australia. The paper describes briefly the principles of HMC operation. Reference is made to early development work, the pilot plant trials and the acceptance of the technique as a mineral dressing process. The Mitchell Cotts pilot plant at Amdel is described briefly and the results of test work on this unit for the processing of a wide variety of ores and ore types are given. Comments are made on the ob- jectives aimed at in the investigation and results are discussed with particular reference to behaviourial differences between ore types. The process is easy to operate, possesses a high capacity-to-unit-size rating and is capable of a high degree of flexibility. Further developments such as specially prepared and graded media for specific applications, automatic media density control and regulation of media consistency by the use of surface ac- tive agents and polymers have increased versa- tility and sensitivity of control to the point where products differing by as little as 0.02 of a specific gravity unit can now be separated with ease.

Jan 1, 1973