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By H Utama, R Heryadi

The demand for environmentally friendly commercial explosives has increased globally due to concerns regarding environmentally friendly mining activities. Ammonium nitrate fuel oil (ANFO) and bulk emulsion explosives (BEE) are two kinds of civil explosives primarily used in coal and mineral mining in Indonesia. Indonesia is one of the leading countries in coal and mineral mining production and export, with abundant resources; therefore, the consumption of civil explosives such as ANFO and BEE is enormous. The selection and evaluation of commercial explosives are mostly done on the commercial and technical side, and no assessment is made based on environmental aspects. This preliminary study evaluates the economic value and environmental burden of greenhouse gas emissions produced by ANFO and BEE and determines which type of explosives is more environmentally friendly. The combination of environmental and economic indicators, eco-efficiency (E/E), was selected to investigate BEE’s economic and environmental performance compared to ANFO. The life cycle of greenhouse gas emissions of BEE and AN was determined using previously available studies and simple calculations. The cost of the product or explosives was used to represent the economic value. The E/E results showed that environmental and economic sustainability could be enhanced using BEE.

Sep 1, 2024

By J E. Moffatt, N A. Spooner, T J. de Prinse, D J. Ottaway, E Klantsataya, L d. S Teixeira, B W. Smith, T B. Payten, G Tsiminis

Single wavelength fluorescence sensing has been used in the preconcentration of ores for many years in situations where it is typically specific to the mineral of interest. Examples of fluorescence sensing include the sorting of diamonds in diamond mines and the sorting of scheelite in tungsten ores. However, the number of minerals that show useful single wavelength fluorescence properties in the visible spectrum is relatively small, so the application of fluorescence sensing is currently limited to niche application in the minerals industry. Recent developments at the University of Adelaide have focussed upon extending fluorescence signal measurements into the infrared spectrum, as well as investigating multi-wavelength fluorescence known as up-conversion fluorescence. These techniques may not only significantly increase the number of minerals that exhibit fluorescence properties suitable for both identification and sensor-based sorting, but also provide mineral-specific signatures of higher quality than previously attainable. This paper details the research work carried out by the University of Adelaide and funded by CRC ORE to develop a mineral-specific fluorescence sensor. The sensor targets two fluorine bearing minerals, fluorite and fluorapatite, that are common in many base metal ores such as porphyry copper ores and silver/lead/zinc ores. Fluorine is a known penalty element in mineral products derived from these ores, so mining companies need to monitor and control the amount of fluorine in their final product to keep it below commercially agreed specifications. Currently there is no real time sensor capable of monitoring fluorine in the ore feed so monitoring and control is carried out using time-consuming standard sampling and off-line laboratory measurements. The development and application of a real time fluorine sensor will enable the mining companies to monitor and control fluorine levels in the plant, greatly reducing the time and cost associated with producing their mineral concentrates within the prescribed specifications.

Nov 10, 2020

New Caledonia is a major metallogenic unit of the south-western Pacific Rim. Its mineral production is of world significance and it has an unusually well diversified mining history. New Caledonia's main metallogenetic potential is, however, associated with its unique ophiolitic complex and its important mineral- izations of nickel, chrome, cobalt and iron. Gold has been found in all the four basic tectonic elements of New Caledonia: the Central Massif, the West Coast basalts, the ophiolitic complex and the Caledonian North. Some analogies are attempted. Only the Caledonian North has supported mining operations (213 kg Au). More recently tenuous gold indications have been found within the ophiolitic complex, possibly associated with Oligocene plutonism.

Jan 1, 1987

Rare-earth permanent magnetic roll separators, pioneered by our group a few years ago, have distinctly different operation characteristics compared to prior art electromagnetic separators of various types. Many new applications for dry high-intensity (or better: high-force) magnetic separation have been developed in a short time period. It has also been found that the new generation of separators generally are more efficient with regards to removal of weakly magnetic contaminants in glass and ceramic raw materials with minimum loss of valuable product compared to induced magnetic roll (IMR) separators.The latest development is in the area of production of clean magnetic concentrates at high recoveries. It is likely that the PERMROLLR magnetic separator will replace cross-belt and lift-type magnetic separators as a result of this most recent advance.The paper will review the features of the PERMROLLR magnetic separator in comparison with other types of magnetic separators on the market and give examples on applications.

Jan 1, 1990

The provision of electrical power is an important consideration in project development. The first step to be taken in this area is to assess the power requirements of the project. The alternatives of laking a supply from a power authority or providing local generation can then be considered. This requires additional defmition of the probable characteristics of the supply.The availability of authority power in Australia is limited by the extent of the state power grids. Recent developments now allow these grids to be extended and their load capacity increased to meet major load increases at less cost than was previously possible.The options for local generation include diesel, gas turbine, steam, hydro, solar and wind, each having its particular performance characteristics and costs. The choice of fuel for diesel, gas turbine, and steam plant likewise involves consideration of a range of factors. The arrangements adopted for five recent Australian remote development projects indicate how some of these aspects influence the decision on power supply.

Jan 1, 1990

By Johnson RD

The variation in coal properties and the coal seam reduced level can be analysed using partial trend-surface analysis techniques. For the area studied seam reduced level and seam thickness data from the Bulli Coal yield trend-surfaces with a high coefficient of determination, since they have relatively small systematic local and random components in their overall variation. Sulphur content appears to have no significant re.gi_onal trend, and phosphorus content has a very weak regional trend. Other analytical variables have regional trends which are of intermediate strength. The strike-directions of.the statistically significant first degree! trend-surface are similar, sug-gesting.: that the variation of the several coal properties was controlled by a set of- related causes. The relations apparent from the dip and strike of the first degree trend-surfaces are similar to- those which are apparent from the trend- surface residuals and'from the results' of canonical trend-surface analysis.'.. It is probable that differential subsidence controlled the areal

Jan 1, 1975

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

Heavy medium separation is widely used because of the precision of separation achievable and the flexibility of control. Good design is manifest in the eventual achievement of the operational objectives. These objectives which take account of the assessed quality of raw feed, market requirements and production cost levels need to be carefully prepared and realistic.

Jan 1, 1987

A new least-squares method for inversion of d.c. resistivity soundings from horizontally layered earth is proposed. Powers are used as measured data. Apparent resistivity is generalized and apparent parameters curves are defined. Estimates for parameter errors are often possible even when data errors are unknown or large. Acceptance or rejection of a model is made an easier decision. Total computational effort is often reduced when compared to global least-squares methods, because although several optimizations are needed, few data points are involved in each, and initial guesses are requested only once and not all at the same time. Correlations between parameters may be used to improve solutions. Precise indications for extra needed data points can be conveyed. A test example is worked out and a field sounding, taken by Rijo (1973, personal communication) in an alluvium-filled river valley in north-eastern Brazil, is studied.

Jan 1, 1987

Froth flotation is widely used for the separation of particulate materials in the world. It is a complex process whose operational behaviour in process plants is difficult to predict. A comprehensive phenomenological dynamic flotation model was presented at the 1982 IMPC. This model uniquely linked the particle/bubble interactions and water transport phenomena to the flotation cell hydrodynamics. The model was used as a dynamic framework to analyse and develop process optimisation strategies. New developments in mineralogical characterisation, real time information management systems and data validation simplify the implementation of flotation technologies for mine to mill grade recovery optimisation. With recent developments in software programming, dynamic simulation enables process engineers to develop process alternatives interactively. This paper presents such an implementation of current process analysis tools and an updated froth flotation dynamic model. It demonstrates how this new environment can be used to improve our technological knowledge of flotation, eg alternative bubble/particle attachment and detachment microprocesses can be incorporated. The dynamic flotation model has several manipulated variables (such as feed flow rate, per cent solids, aeration, wash water flow rate, frother flow rate, specific power energy (impeller speed/delta pressure), cell geometry and tails flow rate) and evaluates the dynamic effects of these variables on grade and recovery.

Jan 1, 2005

By D Purdy, K Wilkinson, P Blake, M Fitzell, J McLellan, L Feltrin, O Dixon

The northern Drummond and Bowen basins region represents one of AustraliaÆs most prospective areas for epithermal vein and stockwork style gold deposits, with both low and high sulfidation epithermal mineralisation known in the region. 3D-GIS reconstructions, numerical and probabilistic modelling (UDEC, FLAC 3D and WofE) are used here to develop a better understanding of the controls operating on the mineral systems of the region and are aimed at enhancing predictive capabilities. An EXTENDED ABSTRACT is available for download. A full-length paper was not prepared for this presentation.

Jan 1, 2008

The granitoid rocks in Burma can be subdivided into three main belts viz. (1) Eastern Granitoid Belt, (2) W-Sn related, Central Granitoid Belt and (3) Porphyry Cu (Au)-related, Western Granitoid Belt. The W-Sn related, central belt Granitoids were interpreted to have generated during the continent-arc collision and the Porphyry Cu(Au)-related, western grantioid belt was emplaced in a magmatic-volcanic arc above an east-dipping subduction zone. INTRODUCTION Major tectonic domains of Burma Burma region can be subdivided into N-S trending (6) major tectonic domains from west to east (1) Arakan Coastal Strip as ensimatic Foredeep (2) Indo-Burman Ranges as Outer Arc or Fore Arc (3) Western Inner-Burman Tertiary Basin as Inter-Arc Basin (4) Central Volcanic Belt (Central Volcanic Line) as Inner Magmatic-volcanic Arc (5) Eastern Inner-Burman Tertiary Basin as Back-Arc Basin and (6) Shan-Tennasserim Massif as ensialic, Sino-Burman Ranges (Bender, 1983). The Sagaing (transform) Fault and Shan Boundary Fault form as a tectonically significant boundary between Eastern-Burman Basin (Back-Arc Basin) and continental,

Jan 1, 1987

HIGHWALL MINING - DECISION TO MINEUlan had completed operations in the first Open Cut area due to high stripping ratios and the presence of geological features which destroyed a significant portion of the coal in the upper part of the seam. The pit had been abandoned in 1994 and operations had moved to a new location to the north west.

Jan 1, 1998

The large, high grade 3000 and 3500 copper orebodies at Mount Isa lie greater than 1200 m below the surface, and partly beneath the silver-lead-zinc mining operations at the Isa Mine.Since discovery over 30 years ago, the primary data acquisition programs have been integrated with long-term copper production strategies. These potentially sizeable and distinctly separate accumulations of copper mineralisation are the only sources capable of supplementing a decline in output from the 1100 orebody in the 1990s. Within a decade these deeper copper orebodies will become the major source of copper ore.

Jan 1, 1993

By Pollard D. M

In the batch phase disengagement test, an organic and an aqueous phase are mixed together for a known period to produce a dispersion which may be either organic continuous (aqueous phase droplets) or aqueous continuous (organic phase droplets). The continuity of the dis- persion will depend upon the method of init- iating the dispersion, the conditions under which the system is operating, such as temper- ature and impeller speed, and the properties of the liquids, such as viscosity, inter- facial tension and solute content. Once the dispersion has been agitated for the required period, the agitator is turned off and the position of the coalescence interface and the sedimentation interface recorded as a function of time. This will produce a plot similar to Figure 1, where the overall dir- ection of travel of the droplets of dispersed phase is away from the sedimentation inter- face and towards the coalescence interface where the droplets coalesce with the homophase.

Jan 1, 1987

The highland region of Papua-New Guinea is relatively rugged terrain where stream gradients are steep. In areas where porphyry copper deposits outcrop the streams commonly expose primary sulphide mineralization in unoxidized rocks. Stream sediment geochemistry combined with float examination and broad geological mapping proved to be an effective tool for detection of outcropping bodies of mineralization. After discovery, detailed stream sediment sampling, soil sampling and rock chip sampling, together with detailed geological mapping proved adequate to delineate drilling targets. Reconnaissance stream sediment sample density was dictated by geology and access and a density of one sample per 25 Km2, or less, was desirable to ensure a high degree of confidence in the programme. Research indicated that the base metals occur in sulphide form in stream sediment and that the -80 mesh size fraction gave the most reliable results. The evaluation of results from any one area relied on the interpretation of the local geology. Basic histogram methods for determining background and threshold values for metals in stream sediments were

Jan 1, 1973

Rosebery Mine is situated on the west coast of Tasmania and is AustraliaÆs largest volcanic-hosted base and precious metals deposit (zinc, lead, copper, gold and silver). The milling operation has been producing zinc, lead and copper concentrates continuously for over 100 years. RoseberyÆs long life demonstrates the operation to be high grade, and high margin, capable of operating through several commodity price cycles. Paradoxically, throughout this long history the ælife-of-mineÆ as defined by proven and probable reserves has been short. Zinifex has demonstrated its commitment to discover the future of Rosebery with the growth project æProject HorizonsÆ. The aim of the project is to extend the life of mine beyond 2020, with an additional exploration expenditure of $19 million over three years. Despite the maturity of the deposit, early success has confirmed the potential with the discovery of new resources. Mine planning strategic studies are challenging established paradigms of mine production, throughput rates and metal cut-off grades. Discovering the optimal process rate for Rosebery, by examining the æHill of ValueÆ and underground mine optimisation is proving critical to the best exploitation of RoseberyÆs rich resources. The promise of finding a mine within a mine is being realised, with new lenses being delivered by exploration success and real grade/tonnage options optimised through dynamic mine planning. The future of Rosebery is co-dependent on these two areas of discovery. This ensures capital expenditure decisions are informed, to secure the next 20 years of wealth creation and beyond.

Jan 1, 2008

The Ok Tedi open pit mine will have final wall heights in excess of 750m. The behaviour of these excavated slopes will be influenced by the presence of numerous defects. This paper discusses the identification of possible failure mechanisms within the pit walls based on mapped fault and joint data. Results from analyses using these data have formed the basis for the ultimate pit design.

Jan 1, 1994

BECAUSE of the attention given in recent years to the flotation process, there is an extensive range of equipment available to any staff detailed for: the design of a flotation mill. This statement applies not only to the flotation machines, but also to equipment for crushing and grinding, elevating the pulp, dehydrating of concentrates, and the methods of driving the various equipment.Distributed through the Proceedings and Transactions of various metallurgical societies and journals there are many excellent descriptions of flotation mills, their equipment and performance.Whilst these articles describe-in many cases in detail-the equipment in the mills to which they refer, the reasons which govern the choice of each particular equipment are not usually given.

Jan 1, 1929

BHP Minerals Ltd operates an open cut iron ore mining operation on Koolan Island, off the coast north of Derby in the Kimberley region of Western Australia. The mine comprises a number of pits, the largest of which is situated adjacent to the coast on the southern side of the island. The lowest bench is currently at RL +2 m, and the mine has planned ultimate depth of RL -82 m. Mining has already extended below the pre-existing water table level, and below mean sea level. In 1984, an extensive program of drilling, geophysics and test pumping was instigated to evaluate the aquifer hydraulic properties and the nature of the groundwater flow regime. With the aid of computer modelling, predictions have been made of the likely dewatering and depressurization requirements, and a conceptual pumping and drainage system has been designed.

Jan 1, 1986