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By R LEATHAM

Long hole drilling underground has come a long way since 'down the hole' surface drills were first taken underground. The underground miners have progressively developed the use of long hole stope drilling from the 'quarry blast' to a precise and selective removal of ore while leaving the remaining structure as undamaged as possible. To reach this position has involved the development of equipment and explosives to give the desired results. This paper reviews some aspects of long hole stope production drilling.

Jan 1, 1992

By Andersson PO

Boliden Mineral AB Boliden Mineral AB operates nine mines in Northern and Central Sweden, producing zinc, lead and silver concentrates and copper and gold. Seven of these mines use cut and fill (C&F) mining with a total production of 2 Mtonnes of ore per year.

Jan 1, 1998

By M Rankin, F Medina, R Verburg

We conducted a preliminary assessment of an extensive deposit of historic tailings discharged over a period of 40 years to the shoreline along a Southern Peruvian coastline. The tailings formed an extensive beach approximately 2.4 km long and 300 m wide. The tailings consist principally of pyrite (37 to 59 per cent), hematite (nine to 20 per cent), magnetite (three to 13 per cent) and quartz (11 to 36 per cent). The present operating company was required to evaluate the feasibility of capping the ocean side tailings deposit, however, given the size of the undertaking and the potential to reclaim residual minerals from the tailings, it was prudent to first evaluate whether capping would in fact reduce the impacts to the marine environment. Therefore this preliminary assessment examined: 1. metals contamination in tailings, shoreline porewater and marine sediments; 2. reactivity of tailings and acid generation potential; and 3. the potential for biological effects from metal contamination in the uplands tailings (solid phase) and beach porewater. Based on mineralogy, column leach studies and chemical results, the upland tailings have a high geochemical potential to acidify and release metals, especially copper, nickel and zinc, should they be subject to oxygenated and aqueous conditions. But, the extreme arid climate results in very low potential for precipitation and virtually precludes the transport of acid drainage reaction products from the upland tailings towards ocean. Wind erosion caused by offshore winds is likely a small source of tailing transport to the ocean. Since some potential exists to reprocess the tailings in the future, capping does not seem justified at present.

Jan 1, 2003

By R Burgess-Limerick, J Haight

A review of mining automation experiences was undertaken on behalf of the National Institute for Occupational Safety and Health (NIOSH). The research included a review of literature and guidance materials; analysis of automation related incidents and visits to surface and underground mines in Australia, Brazil, Chile, South Africa, Sweden and the USA.

Apr 16, 2024

By A Taheri, G D. Nguyen, M Karakus, S Akdag

During underground mining operations, rock masses are highly subjected to dynamic disturbance caused by blasting, mechanical drilling and earthquakes resulting in strain burst, slabbing and spalling. The dynamic fracture is a significant manifestation of rock failure in deep underground engineering, and it is of great importance to assess the dynamic fracture behaviour of the rock mass under elevated temperature conditions. The correlation between temperature – and loading rate-dependent dynamic fracture mechanism of strain burst is yet to be established. A good understanding of the dynamic fracture behaviour of brittle rock subjected to high-temperature under dynamic loading is required for the prediction of the damage extent during strain burst, and proper design as well as control of the underground rock structures. In this study, dynamic mode I fracture toughness tests are carried out on cracked chevron notched semicircular (CCNSCB) granite specimens to reveal the dynamic fracture characteristics of the brittle rock. For this purpose, a Split Hopkinson Pressure Bar (SHPB) apparatus is utilised to conduct the dynamic tests with various striker velocities on thermally degraded granite. The dynamic mechanical behaviour of granite after high-temperature treatment is examined and discussed. The dynamic fracture toughness is determined and compared for the specimens exposed to different temperatures at various dynamic impacts. The fracturing processes are recorded by a high-speed camera (HSC), and the crack propagation speeds are estimated by HSC image analysis. In addition, the dynamic fracture process and the coupled effects of temperature and loading rate on the dynamic fracture modes are identified by HSC image analysis. Energy partition characteristics in dynamic fracture of granite are quantitatively investigated.

Nov 29, 2022

By A Prill

Safety First and zero accidents are the targets most mines in Australia are aiming for, but manual processes and procedures limit the capabilities and response time in emergency situations. Even with a high safety focus, accidents and incidents still happen, too often with tragic outcomes. Dangerous areas, narrow roads and winding curves are all daily obstacles that threaten workforce safety. Every unforeseen event, such as traffic collisions and other accidents, puts lives in danger and weakens production. Safety must be guaranteed.

May 5, 2022

By Elford H. S, Hughes J. F

The object of this paper is to bring before Members of the lnstitute the very important and much discussed question of scientifically prospecting for ores, oil, coal, etc.The paper is divided into three sections:SECTION l - Description of Geophysical Prospecting methods.(1) Sound-Vibration.(2) Magnetic.(3) Gravitometric.(4) Electrical.(a) Equipotential.(b) Electro-magnetic.(c) Schlumberger.(d) General.SECTION II - General discussion of Cicophysical Prospecting.SECTION III - Appendices.(1) Systematic summary of methods of survey.(2) Table of electrical conductivities.(3) Bibliography.SECTION I - DESCRIPTION O:F GEOPHYSICAL PROSPECTING METHODS.(1) SOUND-VIBRATION.THE transmission of sound waves or vibrations underground will depend on at least three factors: (a) Type of Rock. - Hard, dense rocks wiII transmit sound waves much more quickly than softer, more porous rocks. In the former the speed may be eight times that of the latter.(2) Uniformity of Rock. - Any variation in the texture, hardness, etc, wiII have an effect on and direction of transmission of the waves.

Jan 1, 1927

By Kokubu H, Moro-Oka A

Gaseous desulphurization from hot metal- lurgical slags containing sulphur mainly as sulphide and(or) sulphate was measured under `low at four different oxygen pressures. The total gas rate was from 1.7 to 2,8 litre/min. Crushed slag samples weighing 2 to 12 g were used for the experiments. The amount of SO2 gas evolved from samples kept at 15500 was rieasured over tires ranging from 20 to 300 min. The gaseous desulphurization rate of sul- phide sulphur becomes high as the oxygen part- ial pressure is increased, while that of sul- phate sulphur is high under low oxygen pressure. The effect of basicity on the desulphurization rate of sulphide sulphur in oxygen atmospheres is not obvious in the range of basicity from one to three. Changes in the ratio of sulphide to sulphate sulphur during the run in oxygen axe analysed. Desulphurization reactions and the rate controlling steps are discussed. De- sulphurization phenomena can be explained by inte.-¦ucia.l chemical reaction rate control.

Jan 1, 1980

By Gupta A, Hall ST

The grinding characteristics of quartz which is normally associated with gold bearing ores in Kalgoorlie area was examined in a stainless steel laboratory size ball-mill in the presence of inorganic and organic surface active reagents. The cationic species considered were Fe3+, Cu2+ and Ca2+, and the anions were CO? and S2 as these are normally present during the process of grinding of gold ores in the region. The organic surfactants examined were K-amyl- xanthate, dodecylamine-hydrochloride and the Grinding Aid XFS-4272 manufactured by Dow Chemical The study was primarily based on an examination of the electrokinetic properties of quartz surface in the presence of the grinding reagents. Zeta potential at different reagent additions and pH values in the presence of individual reagents were examined and the corresponding grinding charcteristics determined. A correlation has been indicated between the grinding characteristics, as measured by the -53um size fraction produced, and the surface energy of quartz. It was observed that an

Jan 1, 1978

By R R LARGE

In the past decade mineral deposit models have become an important tool for the exploration geoscientist. By combining genetic theories on the formation of particular deposit styles, with geological, geochemical and geophysical criteria relevant to ore location, it has been possible to more effectively focus exploration effort to the regions and local targets which have the best chance of success. However, such models have their limitations, and must be carefully and critically applied and continually updated as new technical and research information becomes available.

Jan 1, 1992

Modelling of Synergistic Effect of Cyanex 302 and D2EHPA in Zinc Solvent Extraction A comprehensive model is presented to predict the synergistic effect of D2EHPA and Cyanex 302 on co-extraction of zinc and manganese. The experimental results indicated that pH, temperature and the extractants ratio have strong effects on the extraction process. Correlations were proposed to predict the distribution coefficient of zinc and manganese between two phases at different conditions by multiple linear regression. The correlations were simplified by eliminating less important terms by analysis of variance. Optimum conditions (ie pH, temperature, extractants ratio and aqueous to oil phase volumetric ratio) for obtaining maximum separation of zinc from manganese at different zinc concentrations and number of extraction stages were determined. For finding the optimum condition genetic algorithm was used. Comparison the model estimations and the experimental data show that the presented model has good ability to predict the behaviours of zinc extraction system over Cyanex 302 and D2EHPA.

Sep 13, 2010

By Glastonbury J. R

The kinetics of the direct chlorination of, zircon in the presence of carbon was studied at temperatures between 9000C and 12000 C. From the experimental data it is prop- osed that the most likely mechanism for metal oxide (MeO2) chlorination is as follows: At I Surfaceon zMeO2+ZMeCl - MeOC12 (1) At Carbon MeOC12+C+Cl MeC14+CO (2) Surface It.is envisaged that this type of mechan- ism would occur for both the zirconium and, silicon. constituents of the ore. In the above mechanism; the surface re- actions appear to be fast and not rate controll- ing. In a carbon surface deficient bed the diff- usion of oxychloride intermediate through the boundary layer to the carbon surface becomes the rate controlling step. In a zircon surface deficient bed the diffusion of oxychloride away from the zircon surface controls the reaction. This postulated mechanism can be used to ex-, plain the observed experimental effects.

Jan 1, 1973

ecent work on decoppering lead is reviewed; CuS is formed rapidly even from dilute solutions of copper in lead. he mechanism of decoppering is discussed, and an explanation for the retention of metals such as silver in lead is dvanced. As decoppering tin appears to be an analogous process, the Cu-Sn-S system is studied at 300¦C. CuS, hich is not, an equilibrium product, is found in decoppering drosses. In the removal of nickel from lead, Ni3pb2S2 formed; preliminary measurements show the equilibrium nickel content to be greater than that obtained by tirring in sulphur. Decoppering bismuth is thermodynamically favoured, but is complicated by the occurrence of uBiS2. The Cu-Pb-S system is the only one of the four studied where the equilibrium can be calculated simply, as ' resence of ternary sulphide or other phases invalidates calculations based on binary data.

Jan 1, 1970

The Vertical Crater Retreat (VCR) mining method was used to mine two rib pillars at New Broken Hill Consolidated Limited (NEHC) mine at Broken Hill. Experience gained in a trial VCR pillar stope was applied to the design of Panel 3CN pillar (P3CN). Restricted access and a central sandfilled plug in this pillar necessitated the use of angled blastholes and blasting of the stope in two sections. Borehole surveys and close charging supervision were necessary to block, charge and stem the spherical charges in the correct position. The laver sections of the VCR stope with rock walls attained an average slice advance of 2.2 m whereas the higher section of the st.ope between cemented fill walls attained an average slice advance of 3.4 m. Achieved fragmentation was extremely fine. External dilution was assessed at less than 10 per cent. A cement consolidated sandfill exposure of approximately 1300 m2 stood vertically with no significant slumping.

Jan 1, 1983

By N Swiegelaar

Loubert Witbank is a defunct coal mine situated near Ermelo in South Africa. Mining ceased in 1992, and within a short period acidic decant occurred, with a significant impact on the regional catchment. The problem was studied during 1996/1997, and the site remediated in 2001/2002 by the Department of Water Affairs and Forestry. Remediation involved primarily submerging of carbonaceous material, backfilling of voids, and capping of the site. Acidic water with high iron levels was also neutralised and discharged. The project was used to assess the cost benefit of different options to the downstream users, from which target expenditure was derived for the various improvements. The cost benefit analysis for neutralisation provided a basis for the investigation of low-cost neutralisation options that are robust enough to be applied in a remote environment.

Jan 1, 2003

By Stevens P

The Isa Mine of Mount Isa Mines Limited currently produces 5.4 million tonnes of copper ore and 3.3 million tonnes of silver, lead and zinc ore annually. Of this, 5.1 million tonnes of copper ore and 2.2 million tonnes of silver-lead-zinc ore is produced by sublevel open stoping. This paper summarises the capabilities, operating practices and problems encountered with current production drilling practices used to drill sublevel open stopes at Mount Isa.

Jan 1, 1982

By C M. Côte, S Worden, K Svobodova

Mines in Queensland are transitioning to the progressive rehabilitation and closure plan (PRCP) framework. Mine operators are required to select and justify appropriate and viable post-mining land uses (PMLUs) following consideration of the surrounding landscape, community views and the objectives of local and regional planning strategies. The new approach offers opportunities for considering innovative PMLU options and collaborative use of post-closure mine assets, such as infrastructure (power, road/rail, buildings), dams and residual voids. Consideration of regional planning strategies will require a shift in thinking as mine closure is regulated and planned on an individual site basis and selection of PMLUs are commonly considered from this perspective. Planning at regional rather than site-specific scale offers strategic advantages, including the ability to align PMLU selection with the regional context and stakeholder aspirations (which could foster sustainable outcomes); address cumulative environmental and socio-economic impacts; consider options that are only viable at scale (ie across larger geographic areas); establish more extensive and connected ecological habitat corridors; reinstate larger expanses of functional agricultural land; and optimise regional resources (Hattingh, Williams and Corder, 2019). This paper presents the findings from a multidisciplinary project that identified PMLU options within Queensland’s four mining regions: the North-west Minerals Province, North Queensland, Bowen Basin and Clarence-Moreton and Surat Basin (Figure 1). To enable spatial analysis at the appropriate scale and to accommodate geographic diversity, North Queensland was divided into three geographical ‘focus areas’ – Weipa, Charters Towers and Tablelands. Delineation of the areas captured most of the mines within the wider region as well as regional characteristics and features.

Aug 2, 2023

Continuous improvement in environmental management assists in the achievement of sustainability goals for the processing of minerals. The use of regular internal environmental audits (scored or unscored) which form an integral component of an Environmental Management System (EMS), provide demonstrable evidence of this improvement. Case studies are presented for a number of major coal mines in the Hunter Valley, where regular internal environmental audits have been undertaken every two to three months, over periods varying from 18 months to five years. Examples of the benefits of improved environmental performance (driven by the audit process) to sustainable development are provided.The auditing process as described here for coal mines, and coal handling and preparation plants, is equally applicable to the processing of other mineral ores, metalliferous mines, quarries, and oil and gas projects.

Jan 1, 2004

By H Bleuler

A new portal and access drift was constructed by Concrete Constructions for BHPÆs Elouera Colliery, south of Wollongong.The portal area at the base of the Illawarra Escarpment is in soft colluvium material, underlain by highly to moderately weathered sandstone. The area has a well documented history of slope movement or slope creep and one of the main criteria for the design was to minimise disturbance to the unstable slope by limiting the excavation for the portal establishment. This was achieved by incorporating a sloped headwall and gabion wingwalls to accommodate the anticipated creep and groundwater seepage.Main features of the design process also included the provision of both primary and secondary support in a single shell application and the use of canopy tubes to provide support ahead of the tunnel face.The active involvement of the designer during the construction phase and the flexibility of the design concept allowed changes to the support methodology to be carried out as excavation proceeded.This paper describes the design process undertaken for portal establishment and access drift to cater for the variability of the exposed ground conditions along the drift alignment.

Jan 1, 1999

By K Knorr

Desktop X-ray powder diffraction using a D2 PHASER equipped with fast linear detector was performed on several iron ore and mill scale samples. Data were analysed using cluster analysis and Rietveld quantitative phase analysis. The quantitative mineralogy of both materials could be established. Thus the input is provided for understanding the energy consumption and the CO2 emission during iron production. Furthermore, tabletop XRD allows to distinguish iron ore from mill scales and to quantify their mixtures.

Jul 11, 2011