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By M Araos, I Onederra

A novel explosive formulation that substitutes the use of ammonium nitrate (AN) with hydrogen peroxide (HP) as the main oxidising agent has been developed and tested as part of an Australian Coal Industry Research Program (ACARP) project. The main objective was to provide a step-change solution that has the potential to completely eliminate NOx fumes in blasting. The development of this HP/fuel-based explosive started with a comprehensive detonation characterisation program, consisting of unconfined velocity of detonation (VOD) measurements of samples at different diameters, densities and void sensitisation techniques. VOD results showed that the HP/fuel-based explosive mixtures behaved similarly to non-ideal commercial explosives; in that way mixtures could be tailored to achieve specific detonation performance targets. The next stage of testing in this development involved preliminary confined tests to evaluate the rock breakage potential of the HP/fuel-based explosive mixtures. Fully instrumented single-hole tests were conducted in a limestone quarry. Results from these preliminary trials confirmed the rock breakage performance of HP/fuel-based explosive mixtures. The confined VOD measured in one of the tests was 5100 m/s in a 102 mm diameter blasthole at a density of 0.96 g/ml. The corresponding borehole pressure measurement of this HP charge was 2.61 GPa with a detonation temperature of 2921°C. Based on near-field accelerations, both HP and ANFO charges displayed similar attenuation characteristics in the test conditions. Post-blast observations indicated that the breakage performance of the HP mixtures clearly reflected the in-hole detonation performance measurements obtained, confirming the ability of these explosive mixtures to both fragment and effectively displace the rock mass under evaluation. Further research work continues with the future commissioning of a prototype mixing and delivery unit, the successful completion and analysis of data from multiple-hole trials, and further characterisation work associated with product stability, reliability and performance under different geotechnical conditions.CITATION:Onederra, I and Araos, M, 2015. Detonation and breakage performance of a hydrogen peroxide-based explosive formulation, in Proceedings 11th International Symposium on Rock Fragmentation by Blasting, pp 565–574 (The Australasian Institute of Mining and Metallurgy: Melbourne).

Aug 24, 2015

The Savage River open cut magnetite mine is located in rugged terrain in densely rain forested northwest Tasmania. The mine and concentrating plant are both in the Savage River valley. Pickand Mather Incorporated (PMI) operated Savage River as an open cut magnetite mine between 1966 and 1996. Acid rock drainage (ARD) was first noted in the last ten years of the operation, leading to elevated concentrations of heavy metals downstream of the mine. When operations ceased in 1996, PMI returned the mine to the Tasmanian Government along with a remediation fund of $11.4 million. At that time, the assessed cost of remediation was in excess of $120 million. As a result of the ongoing ARD contamination and to facilitate both a new operation and effective remediation, Goldamere Pty Ltd negotiated an agreement with the Tasmanian Government in 1996, which resulted in the Goldamere Act and the Goldamere Agreement. The agreement has allowed Australian Bulk Minerals (ABM) to remediate the Savage River mine in conjunction with the Tasmanian Government while re-invigorating a previously closed mine by providing ABM with an indemnity against past pollution. ABM can configure its mine and waste planning activities to maximise remediation benefits without fear of future litigation for past mistakes. The effect to date has been the development of a long-term strategy to remediate the Savage River and short-term remediation works such as water management, which provide benefits to the ecosystem. After five years, the Savage River is no longer significantly impacted by ARD for 30 kilometres downstream and trout are now reported within the reaches of the mining lease. The arrangements between ABM and the Tasmanian Government are an example of a genuine WIN WIN situation where co-operative environmental management of the site results in significant improvements and where the æregulatorÆ and the æminerÆ are working together to achieve mutually beneficial goals. The end result is a significant benefit to Tasmania.

Jan 1, 2003

By Taylor MN

The influx of an industrial environment into or adjacent to the indigenous society has in the past frequently caused the breakdown of traditional be- haviour and culture, and the generation of social and psychological impacts on the local population. Successful programmes developed by government agencies and private industry have been implemented in many areas to maintain the cultural environment and still afford the needs for industrial development. The ultimate goal of such programmes should be directed toward eventual operation and management of the established industry by the local population.

Jan 1, 1978

By S Versace, D Arnott, D Bojcevs, A Shaw

The George Fisher deposit is a significant sediment hosted silver-leadzinc resource located 2 km north of the Hilton Mine in NW Queensland. The George Fisher feasibility project involved the completion of underground and surface drilling programs to delineate Measured and Indicated Resource which could be converted to an Ore Reserve through mining and commercial studies. The geological information which was collected and used for the feasibility study included a major program of diamond drilling, predominantly from underground sites, but with some drilling also completed from surface. All drillcore was geologically and geotechnically logged, sampled and assayed. Data was also collected from underground cross-cut and drive development which was mapped for rocktype, ore distribution, structure and geotechnical condition. This new geological data, generated during the Pre-Feasibility and Feasibility stages, was combined with results of all previous drilling campaigns in the George Fisher area to produce a comprehensive database on which geological modelling and Resource estimation could be based. To allow fast and accurate collection and utilisation of data from the drilling program, digital collection processes were used where possible. This resulted in rapid data entry into the project database, significantly enhanced data quality, 100 per cent data ownership within the project team and increased productivity levels. Processes used during the project data collection program are described, lessons learned are related and suggestions for ænext timeÆ are listed using the benefit of hindsight.

Jan 1, 1998

With mining development on hold and other underground works in a slowdown, the development of nuclear wa te repositories takes centre tage on the American rock engineering scene. Three repositorie for commercial spent fuel-in salt, tuff, and basalt-are in the phase of site characterisation and conceptual design, and one pilot project for defense high-level wa te in salt is under construction. A repository design for crystal line rock has recently been postponed.Because of strict quality assurance requirements throughout design and construction, and because of the need to predict and ascertain in advance the satisfactory performance of the underground openings, much intellectual energy has been expended to analyse underground openings in the unusual circumstances of the repository environment. In the long term, these efforts will lead to an improved understanding of rock behaviour and improved methods of underground analysis and design. For the shorter term, a formalised ground control plan was developed, the principles of which may be applied to other types of projects.This paper summarises the status of underground design and construction for nuclear waste repositories and presents some details of the ground control plan and its individual elements.

Jan 1, 1988

By Lloyd F, Bayley F. J

The new South Mine in the Western Deep Levels complex is destined to become an ultra deep project extending to depths of 4 200 m below surface and where rock temperatures are likely to exceed 65 ¦C. Initial estimates put refrigeration requirements at 133 000 kWR. A surface refrigeration plant with an initial capacity of 42 000 kWR has been commissioned and will be used for mining the upper levels.

Jan 1, 1988

The patented "Epytensic" pump of Minnovation Ltd, a multiple piston pump, is used widely on shearer loaders and by partial high pressure watcr jet cutting strategically in relation to cutter picks not only improves cutting rates, but saves power and increases the life of gearboxes and picks, as well as improving dust suppression. The "Face Side Pump", also a piston pump, located on the ranging arm gearhead has advantages over gateroad pumps and shearer body pumps. The "Extraction Drum", hydraulic air mover system, linked with the above innovations and high pressure water, have further advantages in methane and dust removal. Some modifications providing these systems need workshop applications but most are possible underground with minimal changes to shearer profiles and advantages of minimising hosing, along with the other advantages stated.

Jan 1, 1991

Seven papers included in Session 8 of the Third International Mine Water Congress under the heading "Achievements in Mine Water Management & Research" have been reviewed. Only one paper, a case study by Masters on biological treatment of inorganically polluted effluent, has any connection with research in the sense of seeking new, generally applicable knowledge which would advance the frontiers of mine water management. The remainder deal with various aspects of the management of mine water ranging from investigation of the geology of a specific aquifer system through operating dewatering systems to the management of specific effluent disposal problems.

Jan 1, 1988

There are countless petroleum and mineral fiscal systems throughout the world. This is because many petroleum and mineral producing countries have developed their own methods of calculating government take through fiscal evolution or individual negotiation. Those countries fortunate enough to have petroleum and mineral reserves within their national boundaries are naturally reluctant to yield this resource without a reasonable return for their population. As resource companies are perceived to be enormous conglomerates with endless amounts of cash and resources, governments and the general public demand reasonable division of production while these finite resources last. On the other hand, because companies engaged in the exploration for, and production of, minerals, oil and gas have to be large or lucky (preferably both) to sustain the great physical and commercial risks involved, the income and profit figures look so large that the general public sees them as an acceptable target for taxation. Taxation of the resource industry has been one of the industry's greatest cash flow problems through the years. Allen and Seba (1993) attribute this to the fact that the most equitable tax systems are those that affect the widest possible total of the population.

Jan 1, 1996

By Giannini LM, Carras S

A fundamental problem in mine planning is that of determining the "optimum pit limit" of a mine. This optimum pit limit yields information which is considered essential in the evaluation of the economic potential of a mineral deposit, and in the formulation of long -, intermediate -, and short-range mine plans. Since the mid 1960's a number of mathematical techniques based on the "block model" have been proposed for solving this problem. When applied to large ore-bodies the implementation of these techniques, especially the more elaborate ones, poses considerable computational problems. In this paper we report on our work, done jointly with Systems Research Institute of Australia (SRIA), in devising strategies for overcoming these Problems.

Jan 1, 1986

By Bailey S, Avraamides J, Jayasekera S

The anodic dissolution of iron from three different Western Australian reduced ilmenites was investigated using the carbon paste electrode technique. A characteristic current-potential diagram, called a cyclic voltammogram (CV), was obtained for each of the reduced ilmenites. The shape of the CV measured for all three reduced ilmenites was strongly time dependent. The effect of electrolyte composition and temperature on the CV of one reduced ilmenite was also investigated. The results suggest that the initial surface of iron in reduced ilmenite is slow to dissolve and that chloride ions and higher temperatures accelerate the dissolution of this initial surface layer. However, after removal of this layer, the dissolution rate was essentially independent of the electrolyte composition and the temperature.

Jan 1, 1996

By Tucker A. J

An overburden blast utilising horizontal blast holes was successfully attempted at the Ulan Coal Mines during December 1991. The blast reduced operational problems and costs and improved dragline productivity in an area of that contains poorly consolidated sands and clays overlying very hard Permian strata.The fan shaped shot consisted of seven 250 mm diameter holes between 80 and 95 metres long drilled into the highwall face. The holes were loaded with ICI Powergel Gold 25606 bulk Emulsion explosive. The design powder factor was 0.15 kg/bcm for the total shot of 180 000 bcros and 0.44 kg/bcm for the competent Permian strata into which the holes were drilled. Fragmentation from the horizontal blast was comparable to areas conventual blasted. Following the success of this shot further shots are planned for this area.

Jan 1, 1992

Based on a principle developed at a South African Mine, the CSIR developed a device with which the alignment of guide rails in mine shafts could be measured. Originally the technique could only be used to obtain guide misalignment values at the bunton sets. At the time this was considered adequate since it was assumed that guide realignment could only be done at the support points anyway. The technology was developed further and now it is possible to obtain æcontinuousÆ guide profiles from the measurements. Software was developed with which a guide realignment schedule can be drafted and the shape of the realigned guides can be predicted. A measuring system based on this technology is being used to conduct guide alignment measurements in shafts. The data is then analysed and a realignment schedule is recommended in consultation with the mine. Such a schedule may be prioritised so that the worst sections in the shaft are dealt with first. The measurement hardware and analysis software are described. Examples are presented that illustrate the principles and highlight measurement errors. A case study illustrates measurements recorded in a newly equipped shaft. A repeat measurement, 18 months later, shows the effect of recommended realignment as well as the change in guide alignment over this period.

Jan 1, 2005

Better quality at lower cost is today's formula for remaining competitive in a world market. For an integrated steel company, high quality low cost steel production must originate before the blast furnace. In 1979, when U.S. Steel initiated a Quality Management Program throughout its steelmaking operations, efforts began at the coal, ore and flux mines. The objective was to improve the quality and reduce the variability of the critical parameters for steelmaking raw materials, to get the blast furnaces, and subsequently the melt shops, under optimum control. The general details of U.S. Steel's Quality Management Program are discussed and how it was used to promote the desired improvements in steelmaking raw materials. Some of the outstanding results obtained by the cooperative efforts between the mines and the steel plants are reported. The lessons learned by U.S. Steel were through upgrading existing operations and facilities. These principles should now be applied to new projects and the benefits of good quality management should commence from the time new projects are Commissioned.

Jan 1, 1986

The purpose of this paper is to discuss briefly the problems encountered in designing and sinking No 7 shaft, and to present the methods employed in the operation.The illustrations accompanying the paper show the details of the construction of the equipment used in completing No 7 shaft, consequently the descriptions appearing in the text are brief outlines only. Mineral leases Nos 7 and 8, held by the Broken Hill South Limited, comprise an area of 69.5 acres. The length of the holding is approximately 2500 ft.The western orebodies, which are the main producing masses, enter the property at the northern bonndary. Generally, the dip of the orebody is to the west, and the pitch to the south, but local variations occur and even a reversal of pitch has been noticed. The angle of dip is approximately 70 degrees and the angle of pitch 45 degrees.

Jan 1, 1932

By Merry N, Cocks T

The mineral exploration industry is increasingly aware of the importance of the relationship between mineralogical data and geochemical assay results. However, until recently, the cost and time constraints of most techniques for analysing alteration mineralogy have precluded detailed alteration studies. These impediments have been reduced by the development of the Portable Infrared Mineral Analyser (PIMA), a field portable infrared spectrometer that allows rapid (in field) and cost effective analysis of alteration minerals including subtle variations in mineral crystallinity and Composition.

Jan 1, 1995

The current quantity of rejects from coal beneficiation in Australia represents 20 to 25% of raw black coal production. Approximately 80% of the rejects are derived from coarse processing for particles in the 200mm to 0.5mm size range. The safe and enviornmentally acceptable storage of coarse coal rejects is of interest to coal mining companies. Additional public benefit would be derived from the utilisation of a waste product as a source of fill material for civil and mining engineering applications. BHP Engineering has taken a leading role in the design for storage and utilisation of coarse rejects from two mines associated with the Broken Hill Proprietary Conipany Ltd. The tailings dam at Stockton Borehole Colliery (N.S.W.) is to be raised and a study by BHP Engineering has shown that coarse rejects are suitable for the formation of the supporting embankment surrounding a compacted clay core. Transportation and storage of coarse rejects at the Thiess Dampier Mitsui Riverside Mine (Moranbah, Qld) is achieved by a conveyor leading directly from the coal preparation plant to a discharge stacker on the crest of the rejects stockpile. Production of coarse rejects was higher than anticipated for the initial dump design. BHP Engineering has completed a review of dump design with emphasis on safe operating conditions for the conveyors and stacker system. Data on the geotechnical properties of coarse rejects from Australian coal mines are presented. Coarse coal rejects are a material which should not be considered as waste, but as a potentially valuable resource for many future applications. Appropriate engineering design for the storage and utilisation of coarse rejects would result in an improved environment and economic benefits for the Community.

Jan 1, 1987

By Roach C

Exploration on the Callide Coalfield by Thiess Bros. Pty. Limited had reached the stage in mid 1976 where there was a need for a comprehensive appraisal of the coalfield geology. Exploration strategy in 1977 - 1978 was defined by the selection of the most attractive targets. All available literature, reports and plans were reviewed and borehole records assessed. The geology of the coalfield was placed in its regional setting and the genesis of the Callide Coal Measures described in a structural and sedimentological context. Their general form and extent was then examined by the technique of stratigraphic analysis through the interpolation and extrapolation of the available data. A "localized" reserve classification was drawn up and reasonable estimates of the various geological reserves produced, in terms of their reliability and depth of overburden. Quality trend maps were also produced. The resultant "base map" was virtually a summation of all the information to June, 1977, and the basis for the exploration programme in the 1977 - 1978 financial year. The technique allowed for "base maps" to be produced at almost any stage, each one a refinement of its Predecessor.

Jan 1, 1978

IA )W cli',hla cn1cnt fault 7011(-s 0 11Cn cOrnprise a nrc,II of inrcIIinkc(I faults, cvtcnqonal shear and In]rck cxtcnsir>nal vein- fractures. Hydrothermal mineralisation localised around such structures testifies to their importance as conduits for fluid flow. Mesh structures are most commonly developed in situations approximating bulk pure shear but predominantly simple shear meshes also occur. They appear to develop through the infiltration of pressurised fluids into a heterogeneous rock mass with varying material properties. In some circumstances, mesh formation appears to be a precursor to the development of major throughgoing faults. Mesh formation generally involves hydrofracturing (Pf> a3, at least locally) and the condition Pf - 63 to be maintained for the mesh to remain a high permeability conduit, requiring fluid overpressuring at other than shallow depths in extensional-transtensional regimes. The volumetric character of earthquake swarm activity appears to result from the passage of hydrothermal fluids through mesh structures, representing a form of distributed fault-valve action along suprahydrostatic hydraulic gradients arising from magmatic intrusion, compaction overpressuring, metamorphic dewatering, etc.

Jan 1, 1995

Conflicting claims and views on the priming of ammonium nitrate/fuel oil (ANFO) are reviewed; certain fallacies and misconceptions are rectified. Optimum priming systems for a range of blasthole conditions are indicated. Moves towards optimum priming lead to reductions in the combined cost of drilling, blasting and handling the material. With shallow blastholes, two-point priming is rarely warranted. Best blasting results from single priming are usually obtained when the primer is located near, but not at, the bottom of the blasthole. As blast- hole depth increases, two-point priming becomes more reliable and effective than single priming. For two-point priming, primers should be located such that detonation waves in the ANFO collide at grade level or, if preferred, within a hard band in the burden. Where blastholes are very deep and/or strata variations can be appreciable, three or more spaced primers are often justified. The effectiveness of a primer varies with its detonation pressure, diameter and length. Primer properties influence the velocity of detonation (VOD) near the primer, but do not affect the final (steady-state) VOD in the ANFO. Some primers cause 'run-up' (i.e. lower than steady-state) velocities whereas others cause

Jan 1, 1974