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This paper briefly reviews the history of mine haulage trucks. It reviews producti- vity limitations with respect to size or speed. Changing haul requirements once again create the need for more flexible mechanical drive power transmission equipment. The new equip- ment however is designed to provide extended life between overhauls as compared with previous mechanical transmissions.

Jan 1, 1981

By Goodheart B

The Australian Mineral Sands Industry has expanded from the initial export of mixed concentrates in the 1930s, through various development stages, to its current position as a leading world producer of individual mineral products and some further processed products. Opportunities for downstream processing of the separated minerals and locating such developments in Western Australia are reviewed, along with the role of the Western Australian Government in assisting resource development projects.

Jan 1, 1986

By Javad Koleini S M

The sources of arsenic compounds vary from As(lll) oxide produced from roasters to wastes containing arsenic from chemical or mineral processing plants. The removal of arsenic via co-precipitation with iron is currently proposed as an acce

Jan 1, 1994

By Mankosa MJ, Yoon R-H

A reliable scale-up procedure for column flotation must address three important areas of column design, ie column geometry, sparging system and wash water distribution network. The column geometry is dictated by the maximum froth carrying capacity (which determines column diameter) and the bubble-particle attachment rate and particle retention time (which determines column length). The most important factor in the scale-up of an air sparging system is the ability to produce small bubbles in both laboratory and full-scale columns. Other factors, such as energy consumption and maintenance requirements, should also be considered in the scale-up of bubble generators. It is also important to design a wash water distribution system that can properly control the froth stability and maximise the column throughput. Based on these criteria, a successful scale-up example is given.

Jan 1, 1993

By Hoffmann CF, White NC, Tedder IJ, Wood DG

Since the discovery of Pajingo in 1984, the northern Drummond Basin has emerged as a significant new gold province, and has become the focus of intense exploration for epithermal gold mineralisation. Prospects in the Conway area are hosted by felsic to intermediate lavas and volcaniclastic rocks near the base of the Drummond Basin sequence. These Drummond Basin rocks appear to represent favourable hosts to mineralisation because they are cut by structures which could have focussed and channelled fluids on a regional scale, and because they constitute a possible source of gold and, perhaps more significantly, sulphur for the transport of gold. Prospects in the Conway area are up to 15 km2 in area, and are of the adularia-sericite type. They illustrate many of the classic features (siliceous sinters, alteration mineralogy, and fluid characteristics) recognised in epithermal deposits. K-Ar dating of sericite alteration in three of the prospects has produced a range of ages from 283 to 334 Ma, suggesting that the systems are the product of multiple hydrothermal events.

Jan 1, 1990

By A Domanti, C Jewkes

This paper describes the design and constructability issues investigated in the selection of a trenchless solution in comparison to trenched construction options as part of a scoping study for the augmentation of the existing Bulimba Creek Trunk Sewer in Brisbane. Initial work involved the planning of alignment options vis-a-vis ground geology, geotechnical conditions, location and depth of shafts considering potential construction technology, flotation and stability of the tunnel, availability of construction sites and the influence of construction works on neighbourhood properties and the immediate environment. Two design pipe sizes, DN1200 and DN1500, were considered, and factors including jacking forces, specification of product pipes, pipe joints, pipe jacking methods and the associated impacts of ground settlement were carried out. Of particular interest was research on suitable lubricating fluids with the potential to minimise jacking forces and maximise the length of pipeline between launch and reception shafts.

Jan 1, 2008

Traditionally, the development of a mineral resource project goes through a fairly set pattern of decisions from what commodities to search for; where to look; how to locate; what are the reserves; how can they be exploited with optimum returns for all stakeholders; where are the markets and what will be the price received; what financing arrangments? However, due to the unique nature of most mineral resource properties, the relative significance of individual parameters on the ultimate development decision will vary from project to project. Sensitivity analysis in its formal sense is most frequently related to the economic analysis of a project particularly in conjunction with the ultimate development decision making process, and acknowledges the uncertainty of the actual values with their impact on the corporate decision making yardsticks. In many cases, this analysis merely adds more values to confuse the decision makers who may well opt for some subjective rationale to overcome the numeric confusion. However, sensitivity analysis should be used more frequently to exploit the development dollar to its maximum, THROUGHOUT the phases leading to the development decision. It is essential to identify the critical inputs to the various decision tiers in a project as early as possible and direct the funds to ensure that these parameters are determined as accurately as possible. Examples are used to illustrate the need for an even-handed quantification of the parameters which affect the outcome of decisions en route to the final one while minimising the risk in making an optimum assessment in relation to development funds Available.

Jan 1, 1983

In Finland fogging in mine ramps is a common problem. Fog forms when warm and humid exhaust air moves upwards the ramp, where the skin temperature of surrounding wallrock decreases to about 10¦C. Changes in fog thickness and lengths of fog-filled parts of the ramp depend at least on climatic conditions outside, diesel equipment usage in the mine, and the length of working sequence at a time. In this study fogging problems in three different mines, namely Orivesi mine, Louhi mine and PyhSsalmi mine, with different ore types, different layouts, and different depths are presented and compared. All these mines use diesel equipment and the ramp is used as an exhaust air route. In two of these mines the ramp is used as a haulage road and in the other for supply and repairing, checking, and surveying purposes. Measurements of humidity, temperature, air velocity, and dust content were performed in these mines. The measurement results, as well as field observations are presented, compared, and discussed. The results show that fog is observed in areas with high relative humidity values when air temperature and dew point temperature are less than 3¦C apart from each other. Air velocity values were high in many areas. In addition, measured particle concentration values were mainly high in areas, where fog was observed. A short literature review of recent fog formation studies is also presented. It demonstrates the complicacy of the fog formation process. Similarities and differences concerning fog problems in the ramps are found and presented. As already a lot of new information is gained, the continuation of research is considered plausible to find more economical ways of solving and preventing this problem in the future.

Jan 1, 2005

By S C. Dominy

A high nugget effect and the presence of coarse gold characterises many vein-gold deposits. The effective sampling of these deposits is often difficult because of the relatively low concentrations involved and erratic nature of the gold. Geological complexity often compounds this effect. Underground development, in-fill drilling and bulk sampling/trial mining are often required to delineate Ore Reserves. Winzing is an historical technique that was used to gather geological and sampling data during underground exploration. It permits access to the mineralised structure below the current datum to help determine viability. Winzing has always been considered an arduous and dangerous task. Modern technology has led to the development of the Mobile Supersucker, essentially a giant vacuum cleaner. This system permits safe and efficient winzing activities, and allows the collection of bulk samples for grade estimation. Bulk samples from horizontal development have long been collected to help define mineable grade. However, when defining blocks below current development, there has been over-reliance on ineffective æsmall sampleÆ drill data. The Mobile Supersucker permits safe and cost-effective development of winzes and off-winze sublevels.

Jan 1, 2003

By Jepsen L, Gifford M, Thomas G. S

Mine planning requires careful prediction of both the head grade and tonnage of mineralisation. As part of the planning process, operators of the Murrin Murrin nickel/cobalt orebodies (located in the Eastern Goldfields province of the Yilgarn

Jan 1, 1998

By Staunton W. P

The presence of cyanide soluble copper in gold ores can give rise to serious operational and economical difficulties in CIP and CIL operations. Cyanide consumption can result in the ore being uneconomic to treat by conventional means. Loading of copper onto carbon can also have deleterious effects on gold recovery and subsequent stripping and bullion recovery. The recovery of gold from high copper ores has been previously reviewed by Muir, LaBrooy and Cao (1989). Work undertaken for Mt Gibson Gold Project by Australian Mining Advisors with the assistance of the Chemistry Centre (WA) resulted in the patenting of a process and subsequent construction of a plant at Mt Gibson to overcome some of the difficulties encountered with copper. This paper discusses some of the work which was undertaken during laboratory investigations prior to commissioning of the plant and some further considerations for the treatment of high copper gold ores.

Jan 1, 1991

By Gao K, Wu C, Langley J. M, Waugh B, Farrell K

The dissolution of carbon from carbonaceous materials into molten iron is a key step in various ironmaking operations. For example, in new direct smelting processes, carbon in the form of coal is injected into the molten iron bath, which leads to the dissolution of carbon. In foundry operations, typical recarburizer materials can range from high purity graphite to chars. The dissolution performance of these" materials is critical to the operation and could dictate the efficiency and economics of the process.Dissolution kinetics has been studied by various investigators to explain the influence of melt conditions and carbon type (Sahajwalla et al, 1994; Shigeno, Tokuda, and Ohtani, 1985; Orsten and Oeters; 1988; Ganguly and Reid, 1992; Wright and Taylor, 1993). The influence of melt sulphur content on the dissolution kinetics has been characterised (Sahajwalla et al, 1994), with sulphur retarding the rate of carbon dissolution. The carbon dissolution from different sources is seen to vary significantly even under similar melt conditions. This observation has been explained by investigators on the basis of the varying ash content present in the carbonaceous materials. However, ash content alone cannot account for the variability in dissolution kinetics reported in other studies. One such study is presented below.In a recent study (Sahajwalla et al, 1994), pulverised carbonaceous materials were injected into the molten iron bath and the" dissolution kinetics was established. The dissolution of graphite and glassy carbon, which contain almost 100 per cent carbon, was seen to be significantly different when the molten iron contained sulphur. The influence of melt sulphur content was explained on the basis of different wetting behaviour observed.Importantly, the study showed that even pure carbon sources dissolved at significantly different rates. Hence, their performance could not be explained on the basis of ash content.The key difference between graphite and glassy carbon is in their atomic structure. Graphite is highly ordered whereas glassy carbon has relatively poor ordering in its atomic structure. This study showed that the atomic structure in carbonaceous materials can have a significant effect on their dissolution performance.The focus of the present investigation which stems from the past study described above (Sahajwalla et al, 1994), is to investigate the influence of atomic structure of carbonaceous materials on their dissolution into Fe-C-S melts.The specific objective of this study is to determine the relationship between dissolution kinetics and crystallographic character of carbon sources. In order to accomplish this goal, a range of different materials representing a spectrum of carbon sources have been chosen for the investigation. These materials include brown coal char, two types of Auscarb (A and B), and commercial graphite. Auscarb is prepared by calcining Auscoal at 1000°C. Auscoal is made from chemically cleaned Australian coals (Bowling, Chandler and Waugh, 1990). Part 1 of this paper details the dissolution performance of the materials studied, while Part 11 describes the X-ray diffraction study. The relationship between the atomic structural dimension and dissolution rate constant is discussed in light of the results obtained.

Jan 1, 1996

After extensive testing and a period of plant trials to establish the benefits of Caro's acid (H2S05) as an alternative oxidant, Queensland Mines Limited (QML) decided to replace pyrolusite with Caro's acid in its acid leach uranium treatment plant at Nabarlek. The decision was based on the reagent savings and environmental gains associated with the removal of manganese from the process liquors, as well as the labour savings and improved oxidation reduction potential control possible in leaching using the Caro's acid system. The permanent Caro's acid generating plant was designed by Interox Chemicals Pty Ltd of Australia (IC) to suit QML's require- ments and differed from the unit used during the plant trials. Commissioning of the plant was completed in April 1983 and it has been continuously used since that date.

Jan 1, 1984

By Osborne V. J, Urbank W

An explosion occurred at Moura No. 4 underground coal mine in Queensland on 16 July 1986 and resulted in the loss of 12 lives. The official report of the accident concluded that the most likely source of ignition was the flame safety lamp. This paper describes an investigation of the behaviour of a flame safety lamp, similar to the one involved in the Moura explosion in atmospheres of methane, coal dust and air, carried out at the Queensland Department of Mines . Testing and Research Station. The behaviour of the lamp is described in conditions of varying methane and coal dust concentrations in air, and varying air velocity. Particular emphasis is given to the 'phenomenon of burning which occurs inside the gauze and which is capable of causing the ignition of an external explosive atmosphere.

Jan 1, 1988

By K H. Esbensen

The critical role of representative sampling is featured and illustrated by selected examples from the geosciences and beyond. As there already are many demonstrations of the potential (and potentially large) economic consequences of ignoring proper standards with respect to representativity, eg for mining and minerals processing companies, which æstand to lose millions of dollars by failing to optimise exploitation of their mineral resourcesÆ, such need no further iteration here.This keynote lecture, rather, takes a point of departure from the opposite perspective: what is to be gained by a scrupulous stand for representativity? Honesty, reputation, credibility, market advantage - is what!CITATION:Esbensen, K H, 2012. The critical role of representative sampling, in Proceedings Sampling 2012 , pp 9-12 (The Australasian Institute of Mining and Metallurgy: Melbourne).

Aug 21, 2012

By Eaton R. A

The design of most underground mining machines shows little evidence of regard for ergonomic principles and operator comfort. Likewise, efficiency and ease of operation often appear to have been given little consideration in machines where ruggedness and simplicity have tended to dictate the configuration. Improvements in productivity are amongst the benefits to be gained by a different approach to machine design. The paper describes the philosophy and features of a test bed Load-Haul-Dump Vehicle undergoing trials at Mount Isa Mines. This machine is the outcome of a Research and Development Programme conducted by the Department of Mechanical Engineering at the University of Queensland and Mount Isa Mines Limited. The diesel powered test bed features an enclosed, air conditioned cabin, with a suspended operator's control station and electrically operated controls. An electronically controlled hydrostatic transmission incorporating wheel slip control, is another innovation. The performance and operator acceptance of the machine has led to adoption of most of the concepts in a new machine now being put into production.

Jan 1, 1987

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

By Large RR

Precious metals in the Rosebery north-end orebody occur predominantly in sphalerite- galena-pyrite ore and to a lesser extent in massive barite mineralisation. Gold may also occur in the upper parts of pyrite-chalcopyrite ore (although this ore type is usually gold poor), in pyritic mineralisation lateral to base metal sulphide lenses and in the footwall (very patchy). Although present, remobilised precious metals do not occur in economically significant quantities. Mineralogically, silver occurs dominantly in tetrahedrite and, to a lesser extent, argen- tiferous galena. Gold occurs as electrum associated dominantly with pyrite and, to a lesser extent, tetrahedrite. Geochemical modelling suggests that silver was probably transported as a chlorocomplex, while gold was transported dominantly as a thiocomplex, although at high temperature gold was transported as a chlorocomplex.

Jan 1, 1987

By Forster I, Thilo A, Dean AK

A prototype production tool capable of operation in the hole sizes (

Jan 1, 1988

By King RP, Kientzler P

In recent years, ultrasonic comminution technology has been developed at the Utah Comminution Center. An ultrasonic grinding device was assembled and investigated. An ultrasonic transducer system has been significantly improved by using a special type of piezoelectric ceramic and preloading to 4.1 x le kPa to obtain maximum strength. The improved system provides constant and rapid vibratory promotion of fatigue fracture resulting in more effective breakage. The design principles for an ultrasonic mill are developed in this paper. Size reduction was successfully achieved in the ultrasonic nip-roll device for a variety of materials. Ultrasonic comminution has repeatedly demonstrated the capability of producing fine particles from a variety of materials. A comparison between ultrasonic grinding and dry ball milling of limestone showed that the ultrasonic device produced much narrower size distributions than the ball mill. This trend is especially obvious in the coarse size range where few particles remain, and in the fine size range where overgrinding is prevented. This behavior might have some interesting applications in areas other than mineral processing like powder metallurgy or material science where narrow and controlled product sizes are required for the successful elaboration of high-technology ceramics and glasses. Ultrasonic comminution has a significant advantage in the accurate control of the product size.

Jan 1, 1993