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By Hughes CA

The need to recover metals from low grade deposits, old tailings, etc., combined with improvements in equipment design and the development of new extractants, has resulted in solvent extraction (SX) metal recovery reaching new importance (Webster & Ferron, 1993). The basic principle of solvent extraction is the use of an equilibrium system in which a metal ion is transferred from an aqueous phase into an organic phase, (Equation 1), (Ritcey, 1984). M + E ME . (1) The organic extractant (E) is usually specific for a certain metal ion (M) and forms a metal complex in the organic phase, leaving the impurities behind in the aqueous phase. To recover the metal, the equilibrium is reversed and the metal ion is transferred back from the organic to another aqueous phase in a process called stripping. The metal is then recovered from the aqueous strip solution, usually by electrowinning.

Jan 1, 1990

By S D. Golding

The current study integrates hydrogeochemical and stable isotope results to investigate the sources and evolution of acid mine drainage at the historic Mount Morgan gold mine in Queensland, including the controlling factors and mechanisms of sulfate formation. The open pit and seepage sumps contain acid-sulfate waters and show elevated Al, Cu, Fe, Mn, Pb and Zn values. Samples collected from the Dee River bordering the mine site are less acidic, with lower concentrations of dissolved metals that gradually attenuate downstream from the mine. Concentrated acid mine waters has lead to formation of efflorescences consisting mainly of hydrous Fe-sulfates. The results of the ongoing isotope analyses on water samples show distinctive grouping of the data. The range of the sulfur isotope values for dissolved sulfate in samples from the open pit and sumps (d34S = 2.1 to 3.0 per mil) are similar to those of sulfides in the Main Pipe mineralisation (d34S = - 0.2 to 2.8 per mil). The lack of fractionation between sulfides and sulfate indicates that intermediate oxidation states of sulfur are not significant and makes this technique a useful tracer to identify the sources of sulfate. The Dee River samples, on the other hand, have heavier sulfur isotopes (d34S = 2.8 to 5.0 per mil). These samples may contain dissolved sulfate from æinternal sourcesÆ in the river basin, show local bacterial reduction or indicate a simple mixing trend. Further isotope analyses including oxygen isotopes of dissolved sulfates will enhance the interpretations.

Jan 1, 2003

By P Trotta

The majority of water to the Olympic Dam mine and the nearby townships of Roxby Downs and Andamooka is supplied from the Great Artesian Basin (GAB). There are no permanent local water sources available to Olympic Dam. The use of water from the Great Artesian Basin by Olympic Dam receives considerable attention by BHP Billiton and is extensively regulated by the Government of South Australia. Olympic Dam has robust business management systems in place to ensure the sustainable use of water from the GAB including ISO9001 and ISO14001 systems to deliver the targeted outcomes and obligations of the Olympic Dam Environmental Management and Monitoring Program. The management systems ensure that Olympic Dam retains accountability for its water demand from the GAB over the life of the mine. This accountability has delivered continuous improvement in water use efficiency driven by operating discipline, implementation of water saving projects, using water on a fit for purpose basis including substitution from non-GAB sources, and risk management to prevent and mitigate water supply disruptions to Olympic Dam and Roxby Downs. Since the establishment of Olympic Dam, BHP Billiton has funded a reduction in GAB water flow from bores, previously going to waste, that is greater than the annual average flow used by Olympic Dam.

Jan 1, 2009

By Thompson M

The humble gabion basket is to mine development what the light bulb and safety pin are to eir-ryday life. Gabions provide a flexible, easy to assemble and cost efficient solution for "101" mine and civil engineering development applications.In some instances gabion baskets are still efficiently in use after many years of faithful, maintenance-free service. In other situations, the baskets have been demolished or made redundant within days, either having served their temporary usefulness or negligently destroyed by the operator of heavy equipment. Either way, the gabion basket must surely rate among the top 10 cost efficient engineering construction materials.

Jan 1, 1994

By Jacobsen L. K, Gross K. B

This paper, describing milling practice at Mount Isa Mines, is one of a series covering milling methods and costs that is being published by the Bureau of Mines, United States Department of the Interior.The Mount Isa concentrator began operations in May 1931, by treating a mixture of oxidized and sulphide ores. Since March, 1935, only sulphide ores have been milled; this change involved major alterations to the flow sheet. The maximum capacity on mixed oxide and sulphide ores was 2,650 tons per day; the present capacity is approximately 1,880 tons of sulphide ore per day. The installation of additional Grushing, grinding, and flotation equipment when completed early in 1939 will increase the maximum capacity of the concentrator to 2;240 tons of sulphide ore daily.All tonnages in this paper are expressed in tons of 2,000 pounds, gallon measurements in terms of Imperial gallons of 277·41 cubic inches, and costs in dollars at the rate of $4 United States currency to the Australian pound.

Jan 1, 1939

By G J. Sparrow, M J. Fisher-White

A mineral and chemical characterisation study was conducted on ilmenite-rich heavy mineral concentrates sourced from the western sector of the Eucla Basin in southern Australia. Test work involved using X-ray diffraction (XRD), scanning electron microscope (SEM) and electron microprobe-based characterisation methods. Results showed considerable variability in the degree of ilmenite alteration between deposits with TiO2 contents varying from 53 - 63 wt per cent TiO2. Notwithstanding variability between individual deposits, the samples all had [Ti]/[Ti+Fe] ratios >0.5 consistent with a mineral assemblage of hydrated ilmenite or the hydrated, Ti-rich alteration phase pseudorutile (Fe3+2-x Ti3O9-3x (OH)3x). Accessory phases consisted of rutile (primary and secondary), zircon, aluminosilicates, quartz, Fe oxyhydroxides and spinels. Results for the most altered material are broadly comparable with data for ilmenite concentrates from the eastern margin of the basin. The mineralogy of the western Eucla Basin concentrates and the minor element composition of the ilmenite grains suggest they could be upgraded to synthetic rutile by a modified Becher process.

Jan 1, 2008

By Johnston R. F

The factors which influence the reduction of chromite are investigated with special reference to Coobina chromite. This was compared with a South African chromite ore. The reduction characteristics are outlined and the reduction kinetics studied Temperature has the most significant effect, followed by particle size, silica addition and type of coal.Electron microprobe analysis of the products indicates that iron in the chromite is first reduced at temperatures above 1100°C, followed by chromium at around 1200°C. At temperatures greater than 1200°C metallic iron and chromium are formed simultaneously and subsequently give an iron-chromium-carbon alloy. It was observed that the metallic carbide contains a small amount of silicon. The decomposition of the chromite spinel was observed to pass through the FeO.Cr2O3, MgO.Cr2O3 and MgO.AI2O3 forms before slag formation. It is concluded that Coobina chromite is suitable for the production of ferrochrome if direct prereduction followed by intensive bath smelting is used.

Jan 1, 1994

By Mishra BK, Agrawala S

The traditional method of scale-up uses the population-balance model. In particular, the selection function values for a material are determined in a laboratory mill and a variety of correlations are used to scale these values to plant scale mills. For example, the factor D2-5L (D-mill diameter, L-mill length) appears in many power correlations. The number of collisions is proportional to the number of balls (aD2L), the frequency of mill rotation ((x 1/4D-) and effectiveness of impact ((XD), which gives rise to the 'D2.5L' expression. However, what is lacking in this expression is that it does not throw light on the intensities of collisions. In other words, the collision intensities in both laboratory and plant scale mills are implied to be identical. This fact has been very limiting. Alternatively, the collision frequencies and intensity of impacts can be computed with the discrete element code. This code computes the motion and collision of each individual ball in the ball charge. Therefore the number of collisions and the fraction of collisions in the energy range Et, E2.òòE. (collision energy density) are calculated for a given mill size and operating conditions. Then, using the breakage function determined in drop-weight experiments, the evolution of size distribution is computed for a lab mill. The collision frequency and energy density for larger mill sizes are shown. The fundamental theory outlined for the calculation of size distribution is equally applicable for the large mill, which is the basis for scale-up.

Jan 1, 1993

By Hare S. M, Lumsdaine I, O&apos

Converter slag assaying 3.7 per cent Cu is produced by Mount Isa copper smelter at a rate of up to 180 000 tonnes per annum.Priority is given to the processing of ore, however concentrator capacity periodically exceeds that of the mine and the opportunity is taken to treat converter slag. It is processed in batch campaigns, typically through the Copper Concentrator, but the Hilton Concentrator has also been used. Slag and ore are kept as separate as possible, since each has an adverse effect on the flotation performance of the other.

Jan 1, 1993

Nippon Telegraph and Telephone Corporation (NTT) developed a new construction method (the M-2 method) that could drive a long, curved small-diameter tunnel (4>1.2 m) without human labor. This method employs the cast-in-place lining system, using quick-hardening resin mortar, so that it can greatly increase the driving distance and execute both long distance driving (longer than 500 m) and curved driving with a radius of curvature of 200 m. Furthermore, the central control system with a mini-computer in a vertical shaft enables all work in a small-diameter tunnel, i.e., excavation, lining, and transportation of excavated soil and materials, without human labor. NTT conducted several field tests and a Practical Application Test (P.A.T.) under a public road bearing great traffic. Good results were obtained and the practicability of this method was demonstrated. Therefore, from now on, NTT will apply this ii-2 method to drive telecommunication cable tunnels in urban areas. This method will also be applicable to constructing public tunnel facilities, such as for water, sewage, electricity and gas.

Jan 1, 1987

By M Chen, W S. Ng, Y Liu

In the processing of refractory gold-bearing sulfides, pressure oxidation (POX) is commonly known for its role in liberating the gold in solid-solution via oxidation of the sulfide occlusions. For deposits that contain arsenic-bearing species including arsenian pyrite and arsenopyrite, POX serves an important secondary function in the fixation of arsenic, via the hydrothermal precipitation of stable arsenates such as scorodite and basic ferric arsenate sulfate (BFAS). There have been various investigations on the impact of different POX conditions on arsenic precipitation and the stability of the formed phases, but less is known about the changes to the arsenic carrier that occur in the curing stage, which follows directly from POX. The primary function of curing is to coax the dissolution of sulfates to reduce lime consumptions during cyanide leaching, and the slurry is kept at elevated temperatures near 100°C to achieve this. While the arsenic-bearing phases are expected to undergo transformation during this stage, there has thus far been limited experimental evidence. In this study, the effect of curing time and curing temperature on the arsenic-bearing species and arsenic deportment in the POX product has been investigated. Leaching of the curing products was also conducted to examine the stability of the arsenic species in the solid precipitates.

Aug 24, 2022

By Wang J, Ma Y, Jia H

The Hedong Gold Mine is located in the Yan(ai area, tihandong hroo%ill, e. China. It is an underground mine with an annual gold output of some 700 0(H) grams. The orebody is located on the edge of the Wanger Shan metamorphism zone, and the hangingwall of orebodies is thus defined by a prominent set of fractures. The proximity of the metamorphism zone and the inclusion of the fracture set ensure that both the orebody and the country rocks are unstable. The main orebodies dip at an angle of between 40 to 45¦, with a strike length of 160 metres and a horizontal width of 50 metres. Surface subsidence in the area is not permitted. Cut and fill mining is usually practiced. As the mining operation proceeds to greater depths, the ore grade is diminishing and it is necessary to find a more efficient stoping method. Sublevel open stoping with sequential extraction and filling of each sublevel has been designed and applied in situ. This new mining method is called 'sublevel open and fill stoping method' in the mine. Experience to-date is that new mining method is Satisfactory.

Jan 1, 1998

During the past three years Lurgi's Circulating Fluid Bed (CFB) technology has been successfully applied to roasting of refractory gold ores and con- centrates. In comparison with the so-called Stationary Fluid Bed roasting systems, a considerable improvement of gold recovery, to around 95 per cent, has been demonstrated and achieved on many occasions in pilot CFB units and in commercial CFB roasting plants as well. The major reason for such improved gold recoveries is the excellent controllability of the roasting process in the CFB reactor system. Here, temperature, gas atmosphere and solids residence time are more precisely controllable at optimal values during roasting operation in order to achieve the highest possible gold recovery in the subsequent leaching process step. Further dominant benefits of CFB roasting systems are their flexibility with regard to feed material, throughput capacity, dry or slurry feed, almost unlimited oxygen enrichment, direct fuel addition and in situ capture of SO2 in the presence of limestone and dolomite. The system will accept 50 per cent turndown ratio, large variations in feed composition and particle size, as well as a variety of different fuel types. The commercial applications of CFB roasting systems for gold con- centrates have been realized so far at Fimiston, Kalgoorlie/Westem Australia and for whole ores at Cortez, Nevada/USA.

Jan 1, 1991

By Vilela A. C F

In the present work, the process of dephosphorisation of stainless steel was developed in laboratory scale by adopting a high frequence induction furnace, using BaCO3 base flux. By using BaCO3 - CaO - BaC12 - Fe2O3 Flux of about 110 g/Kg-metal, 30 per cent dephosphorisation degree was obtained a stainless steel containing 18,8 per cent Cr and carbon between 0,08 and 2,0 per cent. In addition, a dessulfurisation degree of 89 per cent was achieved too.

Jan 1, 1991

By Smitham J. B, Keast-Jones R

Six Australian coals were selected to determine their potential to produce, ultra low ash (less than 2 per cent) coal by progressive size reduction followed by density separation and/or froth flotation. Density separation in organic liquids is effective in the absence of contaminating liberated mineral matter which can be removed by froth flotation with several cleaning stages. The limit of cleaning of these coals was an ash value of 1 per cent while commercially attractive yields were obtained at 2 - 3 per cent ash depending on the coal.

Jan 1, 1987

By D Caffrey

To demonstrate the advantages of using electronic delay detonators over pyrotechnic detonators, a trial using the DNES Dynatronic System was conducted at the KCGM Mount Charlotte operation in 1998. The trial clearly demonstrated that accurate control over the firing delay time between blastholes can lead to fragmentation improvement and ground vibration energy control which are two important issues for the Mt Charlotte underground operation. Excellent fragmentation was achieved by employing a 12 ms delay sequence. Detailed fragmentation analysis has shown a 10 to 20 per cent passing increase for the rock fragment size from 0.1 to 0.4 m compared with the pyrotechnic detonator firing. There was no increase in ground vibration level on the surface with the electronic detonator firing even though the electronic detonator firing had a much shorter blast duration than the pyrotechnic detonator firing. In fact, our energy calculation has clearly shown that much less energy had been propagated to the surface from the blast using electronic detonator firing.

Jan 1, 1999

By C J. Moran

Given that the mining industry is committed to sustainable development principles and that Australia is experiencing changes to the regulatory environment that aim to modernise the water sector and encourage adoption of consistent approaches, there is a well defined need for the Australian minerals industry to develop a water accounting framework. This requires: key terms and definitions for water metrics for use in the Australian minerals industry that is consistent with the wider water sector, a suite of metrics representing key components of an operationÆs water balance, a calculation method for some of the metrics, and a reporting protocol. This paper presents the methodology that was used to derive these four components. Existing accounting frameworks were reviewed and key terms and definitions that were consistent with current requirements were proposed. A calculation methodology was developed to obtain some of the key indicators and variables that cannot be easily measured directly (water loss through evaporation is an example). The adopted terms and definitions dictated model development, with the conclusion that a systems approach was the most effective calculation process. To test the proposed definitions and calculation methodology, values for water metrics were derived for eight sites. The proposed framework and definitions could deal with the specific situations selected as case studies. The associated calculation methodology produced complete accounts at various levels. Some elements of the accounts could be directly checked against available data and simulations. The framework captured well variations in the reuse efficiencies; reuse efficiency could even vary for similar processes. It is concluded that this preliminary accounting framework provides a consistent language and metrics for quantifying and communicating water management, both at the intersection of the site with the surrounding landscape (through detailed reporting of site inputs and outputs) and within operational activities. Using this consistent framework for quantifying and documenting water use within an operation will provide a platform for compiling and comparing minerals industry water use with other sectors. This may support benchmarking activities within regions or companies and help demonstrate leadership amongst water users in water resource stewardship. The approach presented here is applicable to a wide variety of mining and processing activities, and biophysical environments, and can be adopted as the first step towards developing national water accounts for the Australian Minerals Industry.

Jan 1, 2009

By Liu Wenyong, Huang Yucheng, Yang Ba

High-water rapid-solidifying material, called æhigh-water materialÆ, is a new material developed by the authors over many years. The material can solidify nine times its volume of water into solid. The material is a fine kind of binder with special properties. The solidifying body of high-water material with water has quite a high early strength. The compressive strength of the material within three days can reach the same strength as conventional Portland in 28 days. One ton of the material can replace three tons of conventional Portland cement as binder. Some important achievements have been made in application of high-water material. In metal mines, based on the material, a new full-tailing cemented backfill technology has been developed. The characteristic of the new technology is that high-water material is used as binder and full tailing or alluvial sand is used as backfill aggregate. Because of the application of the new technology, major technical problems in backfill technology such as classifying of tailing, dewatering, transportation of pulp, low strength of backfill body, environmental contamination and so on, have been solved.

Jan 1, 1998

By D L. Kennedy

Many aspects of the physical layout of manufacturing plants and storage facilities for explosives are governed by so-called quantity-distances tables. Both the British and the American tables were originally derived from an analysis of the injuries and the building damage documented by an early 20th century compilation of significant accidental explosions. However, progressive changes in explosive process technology and in building techniques have reduced the relevance of much of this historic data set. Extensive scientific research has been conducted over recent decades to characterise the potential injuries and damage from accidental explosions under more modern conditions. This presentation will showcase some of this research.**This is an abstract only. No paper was provided for this abstract**

Nov 8, 2011

The approvals process for a major cut-back is not a simple exercise when a mine is located alongside the community. Kalgoorlie Consolidated Gold Mines (KCGM) has been through an extensive process of government, JV owner and community consultation to ensure that necessary permitting processes and detailed studies have been completed to allow this six year extension to the open pit mine life to be achieved. With the Kalgoorlie Boulder community being on the doorstep of the mine, it is critical to ensure that the operation runs smoothly and complies to the license conditions to achieve the full value of the Golden Pike cut-back, and leave behind a sustainable legacy for the local community. This is an ABSTRACT ONLY no paper was prepared for this presentation.

Jun 1, 2010