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By Butler RD

The Singhbhum Copper Belt is an arcuate zone of verthrusting which extends over a strike length of about 180 kilometres, located in Eastern India, 150-300 kilometres west of Calcutta. The Belt is noted for its mineralisation, and both copper and uranium are currently being mined within it.

Jan 1, 1990

Working thick coal seams in Poland is a very serious problem. Nearly 40 per cent of all coal is extracted from seams more than 3 m. thick. In absolute figures this represents about 70 million tons of coal per year. Working seams with thicknesses up to 3.5 m. does not present, at present, major difficul- ties. Working thicker seams calls for a steady improvement in order to increase the degree of utilization of the deposit and to enlarge the concentration of output. The problem is sometimes more difficult because, in many cases, the seams are worked under protected surface structures which compels the mines to use hydraulic stowing with all its advantages and disadvantages. Rock burst hazard, the control of which is the basic problem hindering the mining, is a further problem. The mining systems used in Poland are adapted to these natural and technical conditions.

Jan 1, 1976

By A He, J Li, J Pan, J Clout

The removal of sulfur from SO2 containing flue gas is improved by adsorbing SO2 into solution with manganese ions as catalyser, however, burnt lime slurry has to be added to modify solution pH and the CaSO3 by-product is of low economic value. In this paper a novel one step process for simultaneous manganese leaching-desulfurisation of flue gas is presented. An investigation of the effect of process parameters included flow rate and SO2 concentration in flue gas, adsorbing time, solution to solid mass ratio, leaching time, and their impact on the oxidation and removal of SO2 from flue gas. The catalysing mechanism of manganese ions on the oxidation and SO2 removal was demonstrated by calculation of the species originating from manganese ions and SO2 in the solution according to solution chemistry. SO2 removal in the adsorbing solution took place at pH 5 - 6, where manganese ions dominantly occurred as Mn2+, and the chain reactions for oxidation of SO2 starting from HSO3- were improved by the presence of Mn2+. SO2 bearing flue gas was effectively desulfurised by leaching rhodochrosite (MnCO3), with desulfurisation of the flue gas and modifying the solution pH being achieved simultaneously, and MnSO4 of high economic value recovered from the leachate. 85 per cent manganese leaching and over 70 per cent desulfurisation of the SO2-bearing flue gas were achieved with only one adsorption stage under optimum conditions.

Jan 1, 2004

By Scott SD

The 1986 PACLARK Expedition established that propagation of a seafloor spreading zone into continental crust has created a complex series of volcanic basins on the floor of the Western Woodlark Basin. In addition to abyssal basalts, felsic volcanic rocks were recovered - especially at the leading edge in the extreme west. A recent deposit of hydrothermal Fe-Mn oxides was discovered on an axial seamount of basaltic andesite, and seawater plume anomalies suggest current hydrothermal venting elsewhere. As a modern analogue for the settings in which ancient volcanogenic massive sulfide orebodies probably formed, the Western Woodlark Basin warrants further investigation.

Jan 1, 1987

By Hogan C. J

The compact BWE system set up in 1984 to mine ironsand dunes and the underlying ironsand-clay has been an effective high volume produc- tion unit for New Zealand Steel Mining Ltd at the Waikato North Head ironsand mine. The system utilising two compact S400E (0 & K) Bucket Wheel Exca- vators and a single shared Beltwagon for transfer to the shiftable bench conveyors replaced a fleet of mobile elevating scrapers when the produc- tion requirement was increased by a factor of six. A key factor in favour of the BWE system was the economic advan- tages of low unit costs for both manpower and electrical energy.

Jan 1, 1989

By M Logsdon, T R. Clark, T I. Mudder

Oxidation of pyrite and other metal sulfides is accelerated by the activity of acidophilic iron- and sulfur-oxidising microorganisms. The ideal biocide for controlling biocatalysed acid rock drainage (ARD) would be inexpensive, inhibitory toward sulfide-oxidising bacteria at low concentrations, relatively non-toxic toward non-target organisms, degradable in the environment outside the zone of application, stable and long-lived in the impacted environment, sufficiently mobile to penetrate into piles of waste rock or tailings, and effective regardless of the metal sulfides present. A potent agent for combating ARD that fits these criteria is the thiocyanate anion (SCN-). The objective of this study was to determine the effectiveness of thiocyanate in controlling or preventing ARD within several types of sulfidic waste rock and tailings. Results were evaluated within a context encompassing process water and solids management strategies employed at different precious and base metal mines. Sulfidic rock was treated with solutions of potassium thiocyanate and subjected to accelerated weathering tests in lab-scale humidity cells, trays, and columns. Certain tests also utilised solid phase copper thiocyanate (CuSCN) to evaluate a ærelease on demandÆ strategy. Leach solutions were analysed for parameters indicative of ARD including pH, redox potential, conductivity, acidity, sulfate, iron, and certain heavy metals. Two larger scale field tests were also initiated by personnel at separate mines using, in the first case, ore containing a pyritic component in large columns and, in the second case, waste rock containing base metal sulfides in lined pits. Humidity cell tests showed low concentrations of thiocyanate solution applied to pyritic waste rock could reduce ARD formation by 90 per cent or more compared to untreated controls, with the residual release of ARD components (eg sulfate, Fe, acidity) probably reflective of strictly chemical oxidation of the sulfides by molecular oxygen. Thiocyanate applied at a concentration of 22 mg/kg to waste rock from a base metal mining operation in large laboratory scale columns reduced acidity and sulfate release by 75 per cent to 80 per cent compared to untreated controls. This extent of reduction in ARD may not meet discharge water quality criteria, but has the potential to significantly reduce lime consumption and sludge production in a conventional neutralisation facility. The use of a solid-phase metal thiocyanate compound (CuSCN) at a dosage of 194 mg/kg pyritic ore resulted in the following per cent reductions in leach solution parameters in comparison to controls: sulfate (78 per cent), acidity (93 per cent), dissolved Fe (99.4 per cent), and dissolved arsenic (99.9 per cent). This compound has the further advantage of being relatively stable until needed, dissolving only in the presence of an acidic and oxidising ARD solution. If this line of investigation progresses favorably, it offers the possibility of an ARD prevention technique that may be applicable in some settings. Mine-site pilot scale tests with pyritic ore resulted in reductions in sulfate (56 per cent) and Fe, As (66 - 68 per cent). In sum, thiocyanate at relatively low concentrations dramatically reduced ARD from sulfidic rock in a simulated heap. The pilot test using waste rock containing base metal sulfides has begun only recently. A preliminary process design and cost estimate was made for fullscale application of thiocyanate to waste rock at a hypothetical gold mining operation producing 5000 tpd of ore and 10 000 tpd of sulfide containing waste rock. The combined capital and operating costs for the full-scale thiocyanate application facility were about $US 0.25/tonne of waste rock and $US 0.50/tonne of ore. Although thiocyanate is readily available commercially, it also occurs in process solutions associated with certain types of mining processes. Such solutions after selective treatment might be recycled to sulfidic waste rock or tailings, rather than being treated for thiocyanate degradation.

Jan 1, 2003

By White A, Price G

The main assets of a mining company are its orebodies; the second are the people who find and use them.The graphs in Figure 1 were derived from a paper by Rob Macdonald of Rothschild Australia presented to The AusIMM Centenary Conference in Adelaide earlier this year. They show that the value of the industry on the Australian Stock Exchange halved over the past decade, despite the re-investment of capital equivalent to its full market capitalisation. Why is this so? The average dividend yields for the ASX Mining Index was never above five per cent during that period and barely averaged 2.5 per cent. Why then is $Ai million capital re-investment per employee since 1960 not enough to generate a rate of return to investors better than lousy bank interest? Do the investing public no longer regard our industry's assets to be world class?

Jan 1, 1993

Over the last 100 years in the Polish mining industry considerable work has been done to assess optimum slurry, develop flexible delivery systems and adjust the fill technology to a wide variety of mining and geological conditions. Sand or industrial mineral waste materials for the backfilling of underground voids are used to control ground movement and surface deformation. This paper discusses various criteria to be considered in the preparation of a fill, including slurry properties, mine infrastructure, mining geometry, placement methods and the purpose of the backfill. This paper presents laboratory and in situ test data on the influence of materials parameters on the slurry flow in a pipeline system, stiffness, permeability, binding time and strength of a backfill, on the distribution of mixture in underground voids or the penetration between roof fall materials.

Jan 1, 1998

A proved routine mapping practice is described involving detailed observations on grade and structure. The equipment and methods employed are giving good service under the conditions encountered. Stopes are mapped on every floor whether timbered or open, "Kodatrace" workplans and sections being used, and in addition all development whether in country or lode is mapped.INTRODUCTIONThe accumulation of geological data for application to current mining problems and to the search for new ore involves the necessity for close mapping of all available underground faces and backs. The technique which has been developed to suit conditions at the North and British mines of North Broken Hill Limited forms the subject of...

Jan 1, 1940

Wire rope, when used for hoisting on a mine is the weak- est and most vulnerable unit in the most expensive'-group of installations or! the mine. With the introduction' of hoisting on the S1Koepe"' sheave, a new technique was-established. This innovation brought with it the certain- advantages which long had been recognised and which are being developed further. For many years, drum winders of many types had been the sole means by which ore had been hauled from mines. This type of winder, with its capacity for rope storage on the drum, permitted mine operating personnel to cut short lengths from

Jan 1, 1964

By N Armitage, C Young

In the dynamic realm of mining health and safety, addressing psychosocial hazards is crucial. Legislative requirements now demand employers navigate this complex terrain, but uncertainty often clouds effective management. The resource industry’s skills in managing physical hazards are showcased in their adaptability in this case study. Integrating the Critical Risk Management framework with organisational psychology, a mining company achieved a transformative breakthrough. They identified and assessed psychosocial hazards and established a sustained and risk based approach to managing these hazards within the workplace. This innovative approach encompasses strategic steps. Key learning from the case study was: - Beyond Bow-tie Analysis: Discover why a linear risk analysis tool, like Bow-tie Analysis, falls short in capturing the dynamic and interdependent nature of psychosocial hazards. - Psychological Safety Power: Learn why psychological safety is vital for gathering accurate data and ensuring control effectiveness. - Dive into how it creates a data-driven foundation for success. - Broadening the Brush: Explore the impact of preloading Broad Brush Risk Assessments, an educational and dynamic hazard-identification tool. Control Mastery: Gain insights into how the Critical Risk Management framework ensures ongoing control monitoring and effectiveness for psychosocial hazards. While this implementation’s outcomes are still in their early phases, promising key indicators such as absenteeism, turnover and cultural engagement have emerged. These metrics are set to experience positive shifts as controls prove adequate. As the conference nears, we anticipate having data to showcase these transformative results. Join us in this illuminating presentation as we journey toward a safer, more psychologically resilient workplace.

Apr 16, 2024

We live in a world in crisis. One where the tides of change run ever faster. Where the only thing we can be sure of is change itself. The challenge we face, therefore, is not how to resist the forces that move us nor even to try to predict where they will lead us, but to harness their energy and use their momentum to find new and innovative solutions to problems that can seem intractable. Indeed, crisis is often the catalyst which energises a business to change its technology and to form a partnership with a company which specialises in pioneering new technology.

Jan 1, 1993

The recommissioning of the plant at Mary Kathleen involved several distinct phases. The previous plant process was modified significantly, the plant capacity was increased by the addition of new equipment and the exist- ing equipment was in most cases overhauled. This equipment was either reused in its original duty or relocated. Maintenance requirements after the plant was cmommissioned were high because of the amount of modified equipment and also because some old items of equipment were deliberately not overhauled during recommissioning. The equipment that was overhauled has operated reliably. However some new equipment has not been as satisfactory.

Jan 1, 1978

Maximising margins in today's competitive international commodity markets demands superior productivity. This requires more than selecting the best equipment. It requires continually improving the efficiency of production, commercial, marketing and administrative processes under the control of solid modern management systems.This paper introduces an integrated way of working that includes proven management systems for successfully changing work practices and attitudes, developing managers and increasing accountability. It introduces a proven methodology for systematically involving people in sustained true continuous improvement of processes for maximising productivity, safety and revenue while minimising costs.

Jan 1, 1998

By Sturgul J. R

The South Middleback Ranges (SMR) operation involves the develop- ment of iron ore resources at the Iron Duke mine in the South Middle- back Ranges to replace the Iron Baron mine whose reserves are nearing depletion. The Iron Duke mine will be developed by contract to the stage where it can continue operation at full production when Iron Baron is closed. As part of the mine planning of the operation a GPSS computer simulation model was written to determine equipment requirements. The model simulated the operation of the mine with trucks transporting ore and waste to the appropriate destinations and producing a blended product in the stockpiles. A loader and two trucks would transport ore from the stockpiles to the crusher for one shift per day. The simulation shut the operation down at crib, morning tea, shift change and weekends, and also on the third shift each day. It also modelled operating delays. The results gave equipment operating hours and total output of each material type. The model was modified to produce different outputs from the mine and could be used to determine the most productive shift arrangement.

Jan 1, 1989

After four or so long years at university, where life revolves around lectures, assignments, and drinking coffee strong enough to keep you awake for five nights in a row to finish your thesis, preparing yourself for employment is not an ea

Jan 1, 1994

The paper describes the $US240 million expansion at Hudson Bay Mining and Smelting Co LimitedÆs operations in Canada. The company has been continuously producing copper and zinc from local area mines at its Flin Flon metallurgical plant since 1930. The paper details the companyÆs operational turnaround since 1995 and æThe 777 ProjectÆ which includes: two new mines, expansion and modification of the concentrators, expansion of the zinc pressure leach plant, a new zinc electrolytic cellhouse and the modifications to the copper smelter gas handling system to reduce ground level gas emissions.

Jan 1, 2000

By H R. C Pratt, G W. Stevens

Hydrodynamic and mass transfer performance are presented for a 72.5 mm diameter pulsed disc and doughnut column of the type used by Western Mining Corporation, Olympic Dam Operation, for the extraction of uranium from sulphate media using Alamine 336 as extractant. For the present purpose, 4.0 g/L sulphuric acid was used as solute. The mass transfer data were interpreted in terms of the diffusion model, thus accounting for continuous phase axial dispersion. The results indicated that an efficiency corresponding to approximately one transfer unit over the 1.0 m height of the column was obtained. This efficiency is comparable to that observed by Gottliebsen (1997) for a pulsed perforated plate column using 173 gm/L sulphuric acid.

Jan 1, 2000

By R W. Wilson, A R. Branch

For hot mines, the use of mechanical refrigeration machines has become an essential feature of ventilation and cooling systems. Over the last 30 years, considerable effort has been made in developing refrigeration strategies and equipment to provide cooling that is cost-effective, reliable and energy efficient. In addition to these general design requirements it is necessary to take into account project specific factors such as long term mine cooling needs, operating strategy and installation time. This paper examines a number of actual mine cooling installations which illustrate how these features have influenced the design and installations. For many mines, it is known how the cooling requirements will increase as the mine develops, based on the life of mine plan. The design of the cooling installation must cater for both short- and long-term needs. The initial installation (to meet short-term requirements) must form an integral part of the ultimate cooling installation and as additional equipment and refrigeration machines are installed, it is necessary to ensure that the system remains cost-effective, reliable and energy efficient at all stages. For many mines, refrigeration machines are installed on surface and either operated near-continuously, or for the summer months only. Different maintenance strategies and policies with regard to standby equipment are highlighted for three mine installations. In spite of developments in cooling strategy, the cost of providing refrigeration remains expensive and many mines delay the introduction of refrigeration, as long as possible. When it is finally accepted that refrigeration is absolutely necessary, it is frequently necessary to æfast trackÆ the installation. To minimise site erection time and meet installation deadlines, factory pre-assembly and standardised modular equipment are widely used.

Jan 1, 2005

By Houghton BF

Ruapehu is an extremely active andesitic composite volcano, built in at least four cone- building episodes over the last 250 ka. The volcano was constructed by a variety of extrusive and subplinian, strombolian, phreatomagmatic and dome-related explosive eruptions from summit, flank, and satellite vents. The volcano may be subdivided into the cone itself, of volume 110 km3, and a surround- ing epiclastic ring plain of similar size. Four facies associations can be recognised at Ruapehu,-two each on the cone and on the ring plain. Neither cone nor ring plain provides a complete record of the history of the volcano. The cone is dominated by the products of extrusive eruption, as primary pyroclastic deposits are seldom preserved, being rapidly removed by erosion from the steep water- saturated and/or snow-covered flanks of the cone. The ring plain consists of the products of mostly explosive activity forming an alter- nation of primary pyroclastic fall deposits and material transported from the cone by lahars, floods and debris avalanches and then rapidly reworked in sediment-choked hyperconcentrated Streams.

Jan 1, 1987