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By G Cooper

The Société Nationale Industriel et Minière (SNIM) is expanding its ore and concentrate production capacity in Mauritania, West Africa. This government-controlled mining company has been in production since 1963 and currently exports some 12 Mt/a.SNIM is presently doubling its magnetite concentrate production at the Guelb el Rhein mine. An existing processing line will have a second parallel production line of 4 Mt/a added. The mine is located some 600 km inland from the Atlantic coast in the heart of the Sahara Desert.The metallurgy of the ore is reasonably straightforward. It is a magnetite banded iron formation that is amenable to magnetic separation. While the existing plant uses semi-autogenous grinding and dry magnetic separation, the new processing line will use HPGRs, dry magnetic separation, and a wet milling and magnetic separation circuit for treating middlings.The process choices refl ect the scarcity of water in the region, the high cost of locally generated power and the operating experience and preferences of SNIM. Dust control in the desert environment has been a particular challenge.The metallurgical design aspects as well as the infl uence of the environmental and commercial aspects of the project are presented.

Jul 11, 2011

By K Tungpalan, E Wightman, M Edraki, E Manlapig, L Keeney

The depletion of easily mined high-grade ore bodies resulted in the industry having to exploit lower grade, complex resources (Albanese and McGagh, 2011; Darling, 2011; Randolph, 2011). The trend is now towards mining and processing of low-grade and complex ores (Darling, 2011; Yingling, 1990). Variable geological and mineralogical characteristics, and complex mineralogy and texture can result in large variations in metallurgical response and also cause challenges in processing. (Carson, 1995; Lorenzen and Barnard, 2011; Yingling, 1990). Variability and the complex nature of ores are fundamental sources of risk that often cause the greatest economic impact (Dusci et al., 2007; Williams and Richardson, 2004). Hence it is important to effectively characterise these types of ore bodies and assess their processing performance (ie recovery, grade). To enable this, there is a need for the following: (i) characterisation of geological, mineralogical and metallurgical variability in the ore body; (ii) effective selection of drill core with characteristics that represent the range of ores in the entire ore body. CITATION: Tungpalan, K, Manlapig, E, Keeney, L, Wightman, E and Edraki, M, 2018. A systematic approach of sample selection to predict processing performance of an ore body, in Proceedings Complex Orebodies Conference 2018, pp 67–70 (The Australasian Institute of Mining and Metallurgy: Melbourne).

Nov 21, 2018

This paper outlines the thermodynamic and mass balance principles which affect the distribution of cobalt between matte and slag during the pyrometallurgical treatment of nickel - copper sulphides and considers the implications with regard to maximising the recovery of cobalt from the smelting and converting circuit.

Jan 1, 1992

By Weller KR, Restarick CJ, Stewart PSB

Following a detailed assessment of concen trator performance at Broken Hill South Limited which was reported in a previous paper, the fine grinding section was changed from a parallel arrangement of the two grinding circuits to a series arrangement, and the concentrator per- formance re-assessed. The change to series grinding had virtually no effect on the actual or potential capacity of the circuit to make a final product with 80% passing 100 mesh. However, the fresh flotation feed contained significantly less +150 mesh lead and +65 mesh zinc (material which was shown to float poorly), without an increase in the quantity of poor-floating ultra-fine lead and zinc. From the size-by-size flotation recovery data, it was shown that overall recoveries of both lead and zinc were approximately 1% higher than they would have been without this change in size distribution and it was concluded that this was a direct result of the change in grind- ing procedure.

Jan 1, 1972

My paper presents a discussion of the legislative and departmental requirements in connection with the acquisition of exploration rights for minerals (other than petroleum and coal) in the Independant State of Papua New Guinea, the Solomon Islands and Queensland and he practical problems associated with land entry and land ownership associated therewith. In general there are many similarities in the methodology and philosophy behind the legislation in each country and the contractual requirements established thereby between the exploration company (the explorer) and the government and the mines department or equivalent in each place. There are also a number of differences. I have prepared the paper on the basis that my audience will largely consist of -experienced explorers and the paper is intended to act as a brief refresher and a guide to the philosophy and the practicalities behind the legislation and practices in ground entry in each case. I will deal in turn with New Guinea, the Solomon Islands and then Queensland.

Jan 1, 1987

By D Piason

Newstan Mine commenced mining operations in 1887 and has since undertaken extensive mining within the Young Wallsend, Great Northern, Fassifern, Borehole and West Borehole coal seams using a range of mining methods including board and pillar mining and longwall mining.Newstan Mine is planning to extend the existing mine workings using longwall and miniwall mining methods to produce up to 4.5 Mt/a of run-of-mine (ROM) coal for at least 25 years. The planned extension in the Main East and South West sections will involve developing new longwall panels and related mains headings. The new area contains higher specific gas emissions (SGE) than previously experienced at Newstan Mine. To achieve the optimum ventilation requirements for the longwall operation in this new area, a new ventilation shaft was designed to be constructed using the blind boring method in the South West Headings section.This paper presents the shaft design parameters and selection criteria for the construction of the new ventilation shaft, including the construction phase and the holing process to connect the shaft to the underground workings. The paper also discusses future ventilation requirements for Newstan Mine.CITATION:Piason, D, 2015. South-west ventilation shaft project at Newstan Mine, in Proceedings The Australian Mine Ventilation Conference, pp 229–238 (The Australasian Institute of Mining and Metallurgy: Melbourne).

Aug 31, 2015

By MacDonald AJ, Raffield MP

The South Deep massive orebody consists of 20 to 30 in of payable conglomerates ranging in dip from 11¦ to 20¦ and at depths of between 2400 in and 34(10 in. The mine design process selected a mining method with a proven record of application that could be adapted to overcome the inherent difficulties associated with the depth, thickness and structural influences of the South Deep orebody. A modified cut and fill mining method provides a concentrated and highly flexible method of extraction. An integrated destressing cut will enable the modification of the stress environment such that it is suitable for massive mining operations. The choice of backfill type and stoping width in the destressing cut ultimately determines the characteristics of the stress modification and, as such, is critical to the success of the cut and fill operation. This paper discusses the decision process undertaken to determine the optimum backfill type and stoping width combination in terms of, conditions in the destressing cut faces and in the massive mining environment. Numerical modelling has been extensively used to analyse arious scenarios to aid in the decision process.

Jan 1, 1998

By Hunsaker R. D

The description, characteristics, advantages and application of a new bulk explosive for medium to large diameter dry blasthole conditions is described. A brief outline of the delivery system for the product is also included. This explosive has been designed to provide an alternative to ANFO, currently the most common bulk dry hole product available to the mining and quarrying industry. The selection of the optimum explosive for any blasting operation is of prime importance. It is a major factor contributing to the production of the desired results in terms of muckpile fragmentation, shape and diggability. The optimum explosive can be defined as the most cost-effective in producing satisfactory breakage and displacement of the material. ANFO satisfies this prerequisite for a significant proportion of dry hole applications. This unique, low density and low velocity of detonation explosive has been developed to provide the industry with a cost competitive alternative to ANFO. Typical loading or average inhole densities nominally range between 0.40 g/cc to 0.70 g/cc, depending on the application. Characteristics of this explosive allow for specific and common applications in open cut coal and metalliferous operations. These include ore/waste control operations, prestripping and presplitting applications, sites confronting cap rock problems, and large hole diameter quarries.

Jan 1, 1995

By B M. H Sharp, R P. Hide, S P. Devine

Uncertainty and debate currently pervade the mining industry in New Zealand. The operational uncertainties, whether external (eg gold prices, the exchange rate), or internal (eg coal expansion difficulties), are large. In addition, many wider factors which influence mining are in a state of flux. State Coal Mines, the operating branch of the Mines Division of the Ministry of Energy I may be made a state corporation, with the remaining Mines Division functions being revamped. The agencies administering environmental legislation are to be restructured. Mining legislation amendments have been proposed and then dropped, and the area is now to be reviewed (The Press, 31 July 1985). Some mining licences have been withdrawn, and become the subject of heated debate in the community (The Press, 19 July 1985, and subsequent letters to the editor).

Jan 1, 1985

By P Lukic

The definition of the working sections that will be used in a mine is usually initially made in the field by the geologist supervising the drilling program. These initial definitions are often made on the basis of rules of thumb such as æcoal less than 30 cm thick cannot be mined separatelyÆ; æpartings more than 30 cm thick will be mined separatelyÆ; and æif a coal seam is less than 50 cm thick and the parting above or below is thicker than the coal, the coal will be wastedÆ. These decisions are also often made based on the requirement for a minimum sample mass for analysis, and the desire to collect data at the minimum resolution to conserve the exploration budget.In many cases the geological models based on this data are produced at a resolution that is inadequate to allow the mining engineer to produce a mine plan that will maximise project value. This problem is generally unrecognised.Where data is collected to a higher level of resolution the subsequent processes employed in the production of geological models and mine plans often discards the inherent value that is hidden in this data. Again this problem is generally unrecognised.This paper highlights this problem and then presents a methodology that ensures that the optimal working section is selected and compares the outcomes of applying this methodology versus adherence to the usual rules of thumb.

Sep 26, 2011

By J Boshoff, D Reid

It has been recognised worldwide that the liquefaction risk of unconstrained tailings stacks or cyclone underflow embankments requires careful consideration. The stability of a tailings deposit where the perimeter embankments are made up of hydraulic fill is often governed by post-liquefaction stability.Cyclones are frequently used around the world to classify tailings into a coarse underflow for building a tailings impoundment wall and a finer fraction that is disposed of into the basin. The shear strength of the tailings that form the outer embankment of a tailings storage facility (TSF) and the location of the phreatic surface are the two most significant factors influencing the structural integrity of the facility. The coarse underflow is placed in such a way as to contain the overflow, which is finer, has low strength and is often poorly consolidated.A cyclone field trial was undertaken at a gold mine in Western Australia to assess the feasibility of using the cyclone deposition method to optimise and increase the capacity of an existing tailings cell. The aim of the cyclone trial was to collect information to demonstrate to the client and the regulators that cyclone deposition was a feasible option for raising TSF embankments. The cyclone trial provided an opportunity to assess the cyclone under field conditions and the quantity and quality of the underflow fraction produced on-site. A variety of methods were used to assess the flow liquefaction susceptibility of the tailings underflow sample produced during the cyclone field trial.The field trial, laboratory testing and analysis will be discussed in this paper.CITATION:Boshoff, J and Reid, D, 2015. The resistance of cyclone underflow material to flow liquefaction, in Proceedings Tailings and Mine Waste Management for the 21st Century , pp 151–156 (The Australasian Institute of Mining and Metallurgy: Melbourne).

Jul 27, 2015

By A Mokhtari, S Gatehouse, N Rutherford

Geochemical exploration continues to play a significant role in new mineral discoveries inAustralia and elsewhere, including terrains where mineralisation is buried or otherwise obscured by regolith cover of various types. Transported regolith commonly restricts the migration of trace elements to surface, especially in arid terrains, presenting a range of problems for traditional geochemical exploration methods that employ surface samples. Regions dominated by transported cover include the northern parts of the Tasmanides in eastern Australia and the Yilgarn Craton which are variably covered by thick alluvium and Mesozoic to Cainozoic sedimentary rocks (Anand and Paine, 2002). An EXTENDED ABSTRACT is available for download. A full-length paper was not prepared for this presentation.

Jan 1, 2008

By Chitombo GPF

The dilution of blasted ore with cemented backfill materials has been recognised as a significant factor influencing the economics of some underground metalliferous mining operations. Several mechanisms have heen identified as possible causes of fill failures. The purpose of this study was to determine the possibility of damage as the result of one mechanism, that of production blasting adjacent to bodies of cemented hydraulic fill (CHF). A vibration amplitude transfer function has been developed to model the transmission of blast vibrations from the source, through ore, across the ore to CHF interface and into the CHF mass. The model may be applied in the near field. The model has permitted estimation of vibration amplitude at a point in a CHF mass, to which damage criteria may be applied. A number of assumptions and simplifications have been made to render the problem relatively tractable. Ore and CHF material characteristics recorded by a number of authors were utilised to formulate preliminary damage estimations. A simple application of the amplitude transfer model indicated that a zone of plastically deformed CHF would be produced, and would extend to a distance of approximately 0.5 metres from the interface into the CHF. A sensitivity analysis was also conducted, that indicated that the zone of plastic deformation would be more extensive given appropriate conditions. Recommendations for further model development and future laboratory and field investigations have been made.

Jan 1, 1998

To discuss this relationship both the problems of the mechanisms of ore accumulation and the origin and cause of volcanism must be faced. Volcanic activity is associated with hydrothermal activity but the causes of volcanism are inseparable from the problems of the origin of magmas generally. To be more in accord with the inevitable reaction between water and silicates at high temperature, it is suggested that reconsidera- tion be given to the role of water in magmas such that our general concept of magmas becomes one of hot hydrous pastes rather than melts with water in them. It is claimed that a general concept of magmas as gelatinous hydrosilicate masses is a far better assumption because the rheological and diffusive properties of such materials enables an adequate explanation of a greater number of observations. It is consistent with the mergence of magmatic and metamorphic rocks and requires low to modest temperatures at the time of liquifaction allowing convergence with mobilised and disturbed sediment masses. The physical and chemical properties of both wet sediment pastes and magmas envisaged as hydrolised silicate masses are entirely dependent on the enormous internal surfaces of their disordered solvated components. Mechanical disturbance, such as reliquifaction

Jan 1, 1974

Although AustraliaÆs coal mining industry is currently experiencing a pleasing period of price relief, long-term trends toward lower real prices will surely continue. Higher price levels attract expansion by existing operators and market entrance by new operators. History clearly demonstrates the relentless long-term march toward ever lower real prices. Therefore, the need for economic returns applies constant pressure to improve productivity. To be sustained, high productivity requires a systematic response based on a solid understanding of critical productivity determinants. The most powerful determinant of productivity is now widely understood to be workplace culture. Culture largely comprises a combination of behaviours, symbols and attitudes. This paper will examine and review scienceÆs latest discoveries in human behaviour. It will provide a proven, practical framework for understanding behaviour and applying this knowledge. Significantly, it will highlight why conventional approaches toward improving productivity often provide disappointing economic returns. The modern understanding of behaviour factors will cover coal face operations. More importantly, because executive and managerial levels in coal mining have significantly greater impact on industry and mine productivity the paper will concentrate on leadership. Particular emphasis will be placed on use of modern systems and in particular use of what are by far the most powerful drivers of behaviours û measurement, analysis and reporting systems. The paper and presentation will show how conventional systems rooted in antiquated American legislation from the early 1900s stifle productivity improvement and drive suboptimal and even counterproductive behaviours. These commonly used systems will be compared with accurate and effective modern methods for assessing performance to improve productivity. These principles are proven in all industries and effective application in mining will be highlighted. Actual results will be used to demonstrate practical approaches successfully applied in both metal and coal mining in Australia and overseas.

Jan 1, 2005

By M Paakkunainen

Sampling is often the most critical part in process analysis. When the mean of a continuous lot, such as a process stream within a given time interval, is estimated by calculating the mean of several samples, the uncertainty of the estimated mean depends usually on the sampling strategy. Three different strategies can be used: systematic, stratified or random sample selection. The standard deviation of the lot mean is different for these methods so that systematic sampling usually gives the smallest and random sampling the largest standard deviation. Pierre Gy developed a method where the sampling errors of one-dimensional lots for these three strategies can be estimated from a variogram, which is calculated from a variographic experiment, ie from a set of one-dimensional time series measurements with fixed sampling interval. While variogram is an excellent tool for characterising and displaying the variability of autocorrelated processes as function of time, the sampling error estimation from it is quite laborious, however. In this work an alternative method for estimating the sampling errors was developed. The process is divided into strata of equal sizes, varying the length of strata similarly to variographic analysis. For stratified sampling the standard deviation estimates are obtained by analysis of variance and for systematic sampling by fitting a linear regression line to each stratum and calculating the residual variances. By pooling the individual variance estimates the variance estimates that are corrected for autocorrelation are obtained. The new method was tested with simulated and real data sets having periodic, random and/or drift fluctuations. For stationary processes the results agreed well with the results of the GyÆs variographic method. The method can probably be generalised to estimate the sampling variance of higher-dimensional lots.

Jan 1, 2005

During the first five years of operation, the Lihir gold mine has steadily increased plant throughput rate to over 4 Mtpa, well above the original design capacity of 2.8 Mtpa. Understanding how future variations in ore type impact on plant performance has been an integral part of LihirÆs development program. This paper discusses the key drivers for significant improvements to the plant, including a second oxygen plant, a pilot flotation plant, an autoclave heat recovery circuit, a pebble crushing circuit and additional autoclave feed pumping capacity. The result is a process plant with the flexibility to accommodate variations in ore type without significant loss of throughput.

Jan 1, 2003

We all live in professional silos û comfort zones, where we talk to like-minded people with the same training, experience and view of the world. We note in passing the existence of other disciplines, but they are tolerated rather than embraced. To the geologist, the metallurgist is a mad scientist conjuring gold out of some foul solution about which the less said the better. To the metallurgist, the geologist is a bearded, self-appointed sage who guesses what is under our feet by sniffing the air, and drives a Land Rover badly. As to the view of mining engineers held by both geologists and metallurgists, this is best left to the imagination. And of course we are all confused by the term æmetallurgistÆ. I am called a metallurgist though my skills are in mineral processing not metal processing, but I canÆt be called a mineralogist because that definition is already taken. *Please note that this is available as an extended abstract only*

Jan 1, 2005

By Moskovits EE

Spodumene was recovered from pegmatite by flota.ticn in lAoretory tests and ;pilot-plant, operation using an anionic collector e1 ulsi3.n. i sir_tilar process applied to beryl pegmatite g^.ve encouraging results.

Jan 1, 1963

By F Ouchterlony

Soviet precursors to Cunningham’s Kuz-Ram model from 1983 are described. They are rooted in the mean fragment size and Rosin-Rammler (RR) fits to sieving data and rely on approximations. Three versions of the Kuz-Ram model are presented and all three are de facto based on the median fragment size x50, even if the term mean is used in the papers. This discrepancy caused Spathis in 2004 to suggest a correction procedure for the Kuz-Ram rock factor A, which was said to explain some of the missing fines in the model. This correction, while applicable to Cunningham’s 1983 paper, does not apply to his 1987 paper, in which he presents his own A factor.Common fixes of the Kuz-Ram model’s fines issue are fragmentation models where the fines are mainly generated in a crushed zone around a blasthole. This is contradicted by careful model blasting tests. The lack of a largest block size in the RR function may lead to spurious values of the uniformity coefficient n, eg in conjunction with image-based fragmentation measurements or crusher modelling. These issues may be solved by using the transformed RR function, which has a largest block size xmax or its replacement by the Swebrec function, such as in the KCO model.The mean to median issue is investigated in some detail and it is found that using x50 instead of the mean:has a sounder theoretical backgroundis less prone to errorsis not contradicted by the original Soviet data.It is finally suggested that future work on fragmentation prediction equations focus on the use of distribution independent quantities like percentiles, eg x50, x20 and x80. Some previous work in this direction is briefly analysed and one consequence is that the n-value of the Kuz-Ram model should depend on specific charge.CITATION:Ouchterlony, F, 2015. The median versus the mean fragment size and other issues with the Kuz-Ram model, in Proceedings 11th International Symposium on Rock Fragmentation by Blasting, pp 109–120 (The Australasian Institute of Mining and Metallurgy: Melbourne).

Aug 24, 2015