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Development of the Davcra flotation cell has continued over the past seven years. Preliminary testwork on single cells has now been extended to a com- plete Davcra flotation circuit, to cells ranging from 5 to 400 tons per hour capacity and to cells operating on a variety of materials. Operation of both test and production units has shown the Davcra cell to be competitive with conventional flotation machines. It offers a lower capital cost installation than conventional cells and in addition has a number of. operating advantages, particularly in its adaptability to automatic control.'

Jan 1, 1971

By Grossi M, Baiden G

This paper describes a new mine backfill method based on a newly invented binder with several years of test results from laboratory and on- site applications. The new binder has several advantages over traditional Portland and slag cement binders. One tonne of the new binder can replace two to three tonne of Portland cement when used to consolidate backfill and can result in the same compressive strength within seven days. When comparing backfill slurries of the same pulp density, the new binder attains more volume of in-place backfill mass than Portland cement because of the high crystallisation of water, resulting in tightly filled stopes. The crystallisation of the water provides for less or no de- watering in the backfill stope and easier transportation of the backfill slurry. Pastefill performance can be achieved by using pulp densities typical of a hydraulic backfill and the new binder, all the while transporting with the same ease of hydraulic fill.

Jan 1, 1998

The Canada Centre for Mineral and Energy Technology (CANMET) /Calgary Coal Research Laboratory and the National Research Council in Ottawa established a joint working research group with industry to develop and test various computer models for application in surface coal mining operations in western Canada.The first part of the paper deals with the problems the group experienced during the past two years especially having model specification and requirements defined and understand site management practices.The second part of the paper deals with site specific development of general mine model for TransAlta Utilities' Highvale Mine in Alberta. Described here are the development of an interactive truck/shovel model for their three pit operation, selection and application of dragline model for tandem operation with the extended bench method, criteria for operational model of the five seams operation with selec-tive mining approach.

Jan 1, 1985

By Fuller T

This paper introduces the technology used in laser surveying systems, and the development of a reflectorless one-man total station. These systems are being used for applications such as blast pattern surveys, face profiling, muckpile surveys and the general survey of inaccessible areas. Black Diamond Solutions is continuing to assess new technology and develop integrated systems for applications in the mining industry.

Jan 1, 1995

By M Scoble, R A. Hall

The mining industry has aggressively sought competitiveness through increased productivity and return on investment. A primary strategy has been the pursuit of economies of scale. This has also been dependent upon the implementation of new technology and systems integration. System integration has been accomplished through the implementation of mine dispatch, global positioning and mine wide communication technologies. These technologies have tended to advance at different rates of development and implementation. The result has been that across the industry, and even within companies, mines are at various stages of operational system re-engineering in these areas, driven by improvements in productivity and operational efficiency. Although this strategy has been successful, little effort has been made to analyse change in operational performance in order to understand and model the effects of scale in a quantitative manner. This paper considers the particular impact of equipment scale, together with potential future trends. It then presents and demonstrates a preliminary method to quantify through simulation the anticipated benefits of economies of scale.

Jan 1, 2003

By C Linklater, J Chapman, A Watson

Closure options under consideration at some sites include backfilling mined-out pits with waste rock. Backfill may include mineralised and non-mineralised waste rock. Following groundwater rebound, flow-through conditions may develop in the pit post-closure. The backfill located in the saturated zone below the water table may release solutes under such conditions. It is therefore important to understand the potential impacts that backfilled pits could have on postclosure groundwater quality.Geochemical characterisation programs are the foundation for assessing the potential chemistry of water that has contacted mined wastes. Such programs must be designed to obtain data relevant to the closure options under consideration. To complement standard testing techniques, SRK utilises saturated column testing designed to generate data on leaching rates under anoxic conditions that could be encountered within submerged backfill.This paper presents the findings of saturated column test work carried out on waste rock samples from an iron ore mine in the Pilbara.CITATION:Watson, A, Linklater, C and Chapman, J, 2016. Backfilled pits – laboratory-scale tests for assessing impacts on groundwater quality, in Proceedings Life-of-Mine 2016 Conference , pp 110–114 (The Australasian Institute of Mining and Metallurgy: Melbourne).

Jun 28, 2016

By J Nemcik, E Baafi, I Porter, G Spinks

Spray-on liners used in the mining industry for ground support and stabilisation applications are either cement based (æshotcreteÆ) or polymer based (æthin spray-on linersÆ). Some thin spray-on liners are a blend of both polymer and cement (eg Tekflex). A small number of thin spray-on liners (TSLs) have been trialled in Australia as potential replacements for steel mesh in roadways and other underground mining applications; however, they were found to cure slowly and the cured coatings became brittle after an extended time in place. The University of Wollongong in collaboration with the Australian coal mining industry has shown that a viable polymer-based alternative to steel mesh in underground roadway support applications can be developed to eliminate the use and handling of steel mesh. The work to date has: established the feasibility of developing polymeric alternatives to steel mesh in underground roadway support applications; identified the physical and material constraints to be endured by any new polymeric skin reinforcement system by measuring the mechanical properties of steel mesh; identified materials that can be spray applied; and demonstrated that polymer mechanical properties can be optimised to produce similar mechanical properties (elastic modulus, yield stress, elongation-at-break, etc) to steel mesh. The identified materials will: allow the face support cycle to be fully automated, or at least remotely operated and installed; remove personnel from the immediate face area; and substantially improve underground roadway development rates.

Jan 1, 2008

By Cuff C, Taylor RG, Georgees C

Mineralisation adjacent to Herberton occurs within three main subcentres. The Her- berton Hill subcentre is characterised by the association of Sn,W the Herberton Dividing Range South subcentre by Sn, and the Herberton Dividing Range North by Cu, As. The relation- ships between the subcentres are discussed in terms of metal distribution, production, deposit types, wall rock alteration and re- lationships with granitoid intrusives. The temporal and three dimensional spatial re- lationships between the centres are uncertain.

Jan 1, 1978

The paper describes the geotechnical as- pects of design and construction of two 12 m diameter concrete lined tunnels from the start of design to completion of construction. Prob- lems occurred due to delay in supply of essen- tial rock support materials from overseas and alternative methods using locally available materials were developed. Several major rock- falls and rock movements occurred and remedial measures are outlined.

Jan 1, 1981

Many problems result when coal mine shafts are built in complicated geological conditions and serious shaft lining ruptures have often occurred in the eastern part of China since 1987. Grouting is applied as one of the major measurements for shaft lining ruptures. However, as the general location of reinforcement grouting for shaft lining is deep in or near the bottom aquifer, while using cement grout as the grouting material, the grouting mostly belongs to fracturing grouting in deep alluvium. In these conditions, the mechanism and behavior of fracturing grouting has not yet been understood. From these points of view, this paper describes the mechanism of shaft lining rupture and fracturing grouting and then discusses the effect of grout injection on the stability of shaft lining by means of numerical analysis and field data obtained so far.

Dec 6, 2010

By Estoque J, Lodrigueza L, Rebillon F

Ore mineralization in Masara consists mainly of gold-silver veins, porphyry copper and pyrometasomatic deposits related to left-lateral movements along the Philip- pine fault system and a later stage of magmatism. These are hosted by pre-Tertiary volcanic flows and volcaniclastics, and comprise a temporal pattern of earlier peripheral copper zone, an intermediate mixed copper-gold area and a later central gold vein system within the Masara sector of the postulated volcanic field. Gold ore emplacement occurred in at least two stages, and shows gradations from a lower mesothermal-epithermal phase passing into a typical epithermal zone, and finally into a truncated, or poorly developed, upper level thermal spring deposit. Orebodies are closely associated with hot springs, solfatara and several magma- related masses, emphasizing their inherent linkage with a geothermal system in the Area.

Jan 1, 1987

By N Nosaka

Sinter plants currently have to use many types of ores with different properties due to the great demand for iron ores, which was driven by the massive growth in Chinese iron and steel industry. On the other hand, the development of iron ore mines is limited and the quality of iron ores is in a tendency of deterioration. Therefore, the quick evaluation of iron ores has become more important for a stable sintering operation. In addition to such a background, the CO2 gas emission should be decreased from sinter plants according to the Kyoto Protocol on reduction in greenhouse gases. The present paper first describes the methods for testing the metallurgical properties of iron ores, which use a small volume of sample mainly focusing on magnetite ore that is effective for reducing CO2 and NOx emissions from sinter plants. The sintering properties of ores are evaluated separately according to each stage in sintering process, that is: heating stage before melt formation, primary melt formation in adhering fines layer of pseudo-particles, and assimilation of nucleus ore particle with calcium-ferrite system melts.Next, the application of the tests to the blending ores is introduced showing examples of the studies on the effective usage of the magnetite ores with Marra Mamba type ores.

Jan 1, 2005

By R Cunningham, P Duniam

Late in 2005 it became apparent that cave propagation at the Northparkes Mine was not progressing as planned. By mid-2006 sufficient Reserves were identified to warrant an extensive drill and blast program to assist in cave propagation. This program began late in 2006 and concluded early 2007. A significant challenge faced was the drilling and blasting of holes between 75 - 240 m in length in the South Wedge in Lift 2 at Northparkes Mines E26 orebody. The project set new benchmarks in production drilling and charging in underground metalliferous mining. This paper discusses the drill and blast designs, the challenges and the operational issues encountered with this project. Also highlighted are ways in which these were overcome.

Jan 1, 2007

By L Grigorov, G J. Jame, A V. Nguyen

The dewetting kinetics between a small air-liquid interface and a silica (negatively charged in water) planar surface in solutions of dodecylammonium chloride (cationic surfactant) has been investigated using the Scheludko cell and digital high-speed video microscopy. The gas-liquid interface was created at the bottom of a small silica capillary of the cell and then was moved towards the silica planar surface. After the rupture of the liquid films between the interfaces, the expansion of the gas-liquid-solid three-phase contact (TPC) line was observed and recorded using a digital high-speed video microscope system, operating at 1000 frames per second. The surface tension of the surfactant solution was measured using the pendant drop technique. The equilibrium contact angle was measured using the Scheludko-Minings method with a silica micro-sphere. The TPC radius was determined as a function of time and compared against the available hydrodynamic and molecular-kinetic models. The experimental data are described very well by the molecular-kinetic model for the TPC line motion. The hydrodynamic model is in agreement with the experimental data only for a short time after inception of the three-phase contact expansion.

Jan 1, 2005

Diamonds have been known in Australia for many years, especially in association with alluvial gold and tin occurrences. Exploration for primary sources in the Kimberely area of Western Australia has been carried out since 1968, culminating in the discovery, in 1979, of the Argyle Kimberlite No 1 (AK1) kimberlite pipe. Various techniques have been used in the search for diamonds such as geologic interpretation, aerial photography and Landsat, soil geochenical techniques, geophysics, and stream sediment sampling. Stream sediment sampling, a method developed in South Africa, using the detection of indicator minerals derived from kimberlites in gravel samples, has had wide application and success in Australia. Nevertheless, although Australian diamond bearing kimberlite and lamproite rocks contain some of the classic indicator minerals, their concentrations are generally much lower than in South Africa and Russia. Despite this paucity of indicators, stream sediment sampling is still the best known and most commonly used method of diamond prospecting in Australia. Small samples are treated by hand but larger samples require the use of diamond pans, jigs or heavy media separation plants. Each of these methods has advantages and disadvantages. The final concentrate is passed over a grease table or subjected to x-ray sorting.

Jan 1, 1984

By Chilman G. F, Lean P. J

The New Broken Hill Oonsolidated LImited (NBHC) concentrator was commissioned in 1952 and underwent a number of expansions over the next 25 years. In 1978, the decision was taken to expand further from 1.20 million tonne/yr to 1.43 million tonne/yr. This increase necessitated a substantial modification to an already over-taxed grinding circuit. The circuit consisted of rod mills, ball mills and rake classifiers. Plant data of grinding mill performance was obtained to develop mathematical models of individual units that could be combined to simulate total circuit performance in a number of configurations. The data provided further illustration of the validity of the perfect mixing model for relatively small increments of ball mill scale-up.

Jan 1, 1983

By Wharton P, Voigt R

In order to do the discharge estimation better, it is valuable to find out appropriate formulas for estimating discharge in various pits, based on accumulating data, summarizing discharge patterns applying optimum seeking method and principle, by seeking redical exponent with help of the method of exhaustion, as well as testing and making statistics, in accordance with the quality standards established by our practical experience.

Jan 1, 1988

By Bruce See J

Oxidation of artificial Imperial Smelting Furnace lead bullion was performed during cooling between 1180 and 820°C in order to attempt to produce a tin-rich dross.The addition of sodium carbonate together with stirring increased the tin content of the dross when oxidation was carried out with air or PbO on zinc-free bullion.Zinc in the bullion during oxidation resulted in a decrease in tin concentration of the dross due to zinc oxidation and copper entering the dross.

Jan 1, 1987

By Ypma PJM

The Westmoreland uranium deposits occur on the northern flank of the Murphy Tectonic Ridge in the upper member of the Westmoreland Conglom- erate. Uranium mineralization is spatially associated with the contact of the overlying basaltic Siegal Volcanics and the margins of in- trusive dolerite dykes which are geochemically similar to the Siegal Volcanics. Thermoluminescence (TL) measurements on 800 samples from within the orebodies and surr- ounding host rock (up to 8 kilometres away from the deposits) have indicated that all of the Westmoreland Conglomerate has suffered major radiation damagg attributable to at least 10 ppm uranium over 10 years. The underlying rhyolitic Mid Proterozoic Cliffdale Volcanics have distinctive TL glow curves indicative of radiation sensitization caused by high uranium contents. These vol- canics are part of the Mid Proterozoic volcanic event known to be enriched in uranium. The Westmoreland Conglomerate has been derived by erosion of the uranium-rich Cliffdale Volcanics and associated Nicholson Granite Complex which makes it likely that the Westmoreland Conglom- erate had a high inherent uranium content.

Jan 1, 1984

Analysis of different environmental scenarios and to represent, spatially, of impacted areas is possible by the use of geoprocessing techniques, specifically Systems of Geographical Information (SIG). Through these systems it is possible to create dynamic mathematical models, constituting of a georeferenced digital database and employing the integrated data originated from several sources. In this context, the general goal of this paper is to apply this tool in an environmental analysis of a specific karstic area impacted by mining activities. In order to preserve a limestone site, internationally recognised by its archaeological features, including caverns, lakes and evidences of prehistoric ages, the Brazilian government has created the Lagoa Santa Environment Protection Area. This place is located in the proximity of the Belo Horizonte international airport. In the past two decades exploitations of dimension stones have increased in this area. These exploitations have been done without a mine plan promoting several environmental impacts. The objective of this paper is to analyse these activities using SIG as a basic tool to locate the main mining related impacts and propose mitigation measures including waste and tailings disposal and reshaping of the landscape and introducing a drainage system for the considered zone.

Dec 6, 2010