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By M N. Ingham

X-ray fluorescence (XRF) spectrometry has always been considered to be a comparative method of analysis. Reference materials are required to calibrate the analytical system. This paper describes the use of a set of æsyntheticÆ oxide standards, made from commercially available high purity compounds, to calibrate a spectrometer for 21 major and minor oxides. The spectrometer software uses simple methods of background correction, and a fundamental parameter method of matrix correction. Sample preparation is by fusion in 66 per cent lithium tetraborate, 34 per cent lithium metaborate. The use of synthetic standards, made from traceable compounds, brings XRF significantly closer to being a primary rather than a comparative method. Reference materials were used to validate the method described and examples of accuracy for major constituents are given using ores and other minerals. This method has successfully been used to analyse a wide variety of minerals and ores, as validation data shows. A titanium process example clearly shows the benefits of highest accuracy analysis.

Jan 1, 2008

Rehabilitation has been very effective in the short to medium term in providing a cost effective and reliable means of containing the side effects of land disturbance. However, there is still insufficient data to critically evaluate the sucess of rehabilitation in the long term. There is an urgent need to develop objective criteria to monitor the sucess of rehabilitation. The aim of rehabilitation in Australia has traditionally been to return disturbed land to natural vegetation compatible with the surrounding area. This objective has often been accepted instinctively without adequately addressing alternatives.

Jan 1, 1992

The current boom conditions in the Gold Mining Industry, open cut low grade gold mines have become the initial cash flow source for most companies. To achieve the required cash flow the head grade needs to be maintained at the required level. The methods of grade control to achieve .the planned head grade have evolved various systems, one of which is the Ditch Witch Trencher. The application of this machine has revolutionised open cut grade control and Geology and this paper records the various methodologies developed in the Eastern Goldfields of Western Australia.

Jan 1, 1987

By Quast K. B, Newell R, Caterford J. H

The most common reason for gold-bearing deposits being refractory is the presence of sulphides; in many cases these interfering minerals contain arsenic, antimony, or other environmentally-sensitive elements. A number of processes have been proposed or developed for pre-oxidation of interfering minerals. In most cases developers have focussed on gold recovery and capital costs, with relatively little data on the deportment or form of these potentially harmful elements. This paper surveys recent work connected with pressure pre-oxidation processes. Data from pilot plant treatment of refractory gold materials, using the nitric acid Redox process, is discussed along with the attendant flowsheet and engineering implications. Four refractory gold-bearing materials have also been tested at the University of South Australia for arsenic and antimony deportments.

Jan 1, 1991

In making any attempts to determine the depositional environments in which coal seams accumulated it would be useful to establish whether there is a pattern, or patterns, of development which the majority of the seams have followed. To this end, the distribution of types of coal seam sequences found in the standard petrographic profiles of about a hundred Australian coal seams of Permian and Triassic age has been examined statistically, using the "chi square test" with the limiting probability set at O·Gl.Results indicate that non-random conditions have probably prevailed during the deposition of most of the seams. More samples are needed for conclusive results.The plants, or some other internal feature of the swamp environment, have been the important controlling factor in the development of the seam sequences.Comparison has been made with some British Carboniferous coals.

Jan 1, 1972

By Dobias B

A new separation method based on a combination of coagulation and colum flotation was used to treat fine sphalerite in the range 90 per cent - 15 pm with a relative high superfical gas velocity and a thick froth layer. Minerals studied include sphalerite, calcite, kaolinite and baryte. A new developed sedimentometer was used for sedimentation analysis to characterise hetercoagulation of mixture and coagulation after addition of active ions or reagents. A comparison between use of selective frother and depressant (SHMP) was made to deactivate activated minerals. Selectivity of frother for sphalerite was found in flotation test. The depression function of Flotanol for activated minerals was confirmed in sedimentation alalysis. The use of small quantities of HPAM can improve the flotation of fine sized sphalerite particle and reduce recovery of activated gangue minerals in the neutral or alkaline pulp. A satisfactory separation of fine sphalerite from its gangue was achieved by using alkylpolyglycolether (Flotanol) and copolymer polyacrylamide (HPAM hydrolysed polyacrylamide) as frothing and flocculating agents Respectively.

Jan 1, 1993

By Rogers J. F, Bird A. C

The establishment of vegetation for dust control on tailings dams at The Zinc Corporation, Limited and New Broken Hill Consolidated Limited (ZC/NBHC) is outlined. The evolution of practices and techniques employed is described and the problems encountered are discussed.

Jan 1, 1983

Porgera is located in the Central Highlands of Papua New Guinea. Porgera Joint Venture treats a high grade epithennal gold deposit. Most of the gold occurs as submicroscopic particles in a sulphide matrix although there is some quite coarse free gold. Anticipated gold production is 900 000 oz per year for the first six years of operation.Stage I of the treatment plant consisted of a concentrator and leach/CIP Circuit. It was commissioned in August 1990. Design throughput was 1500 tpd with an anticipated gold recovery of 60 per cent. Throughput achieved was actually 1850 tpd with an average gold recovery of 69 per cent. CIP tails were accumulated in a pond awaiting retreatment by pressure oxidation.

Jan 1, 1992

By R Simonato

It is now recognised that rotary sample division is by far the best laboratory tool for extracting subsamples from a lot of material. In terms of sampling theory, rotary division, by virtue of the fact that it can extract many increments from the lot during the division process, radically reduces the variance due to distributional heterogeneity in the sample being divided. There are a number of occasions in sample preparation when it is necessary to extract a subsample of a target mass. To do this with rotary dividers taking a fixed fraction of the starting mass is a tedious task. In response to this problem, a variable split sample divider has been designed and built for the mineral industry. This paper discusses the utility of the device and presents test data showing that the machine is capable of making accurate mass split while overcoming segregation in the material being divided.

Jan 1, 2008

During the past three years there have been several parties prospecting for oil in the Stat6 of Queensland, and It was: gratifying to read the newspaper headlines last Christmasabout the discovery of oil in the Moohie Nol Well. This discovery was not only a welcome Christmas present for Australia but marked up another success for the seismicmethod in exploration for oil.The purpose of this paper is to discuss the operationaI aspects of seismic work in Queensland with-emphasis on shot-haledrilling. The paper is based upon the experience of one particular seismic survey which began in December of - 1959 and is still inoperation. This survey is being conducted by the Petty Geophysical Engineering - Company of San Antonios, Texas, and the Queensland area involved is in the general vicinity of Quilpie, Dlackall and Charleville.

Jan 1, 1962

The development of the lower Hunter Valley, centred around Newcastle and its suburbs is closely linked to the mining of coal and the settlements which grew to house the colliery officials, the miners and their families. The Port of Newcastle expanded and developed as a port exporting coal to many ports of the world ranging from Hawaii and Brazil to Japan and Korea. The coal which passed through the Port of Newcastle, depend- ing on the historical period in question may have been mined in Newcastle itself, or one of the nearby colliery townships such as Lambton, Wallsend, Charlestown or Hamilton, or from one of the estuarine collieries located at Carrington or Stockton or from the West Wallsend area or from East Greta, Pelaw Main or Cess- nock located on the South Maitland (Greta) coal field or from the open cut and underground mines of the Singleton Coal District.

Jan 1, 1988

By Felice J. J

The assessment of the face velocity of blasts is important in the analysis and subsequent improvement of blast performance. POWERWAVE RADAR is a new tool which will make the collection of this data easier for blast researchers. The data collection technique ensures that a large amount of face velocity data is collected from a blast, and describes the velocity characteristics of the face at a new level of detail. This results in a greater understanding of the effect of drilling and blasting parameters on blast performance. Several case studies are presented which illustrate the collection technique, the type of data generated and how the data is used.

Jan 1, 1992

The different electrowinning cells presently developed for recovery of gold from CIP eluates are compared and contrasted. The efficiency of operation for each cell is,discussed in terms of the electrochemistry of (a) gold deposition, and (b) packed bed electrodes. The advantages and problems associated with each cell design are presented and recommendations are made as to the best method of gold recovery.

Jan 1, 1982

By Turnbull AG

The direct smelting of zinc sulfide con- centrates has been investigated by an extensive series of computer-based thermodynamic equili- brium calculations. The study covers both pure 7.n-S-O-C-N systems and practical concentrate- coal-air-flux systems. It is shown that for a zinc concentrate containing iron and lead sul- tide impurities, a 97% yield of zinc vapour with autogenous operation can be obtained under carefully optimized conditions. The possible integration of this process with existing zinc condensation and recovery processes is Discussed.

Jan 1, 1980

By Kershaw M. G, Maughan R. C A

A process for eliminating nickel from electrolytic zinc plant solutions by precipita- tion with dimethylglyoxime (DMG) was developed to enable the Electrolytic Zinc Company of Australasia Limited (EZ) to treat nickel-bearing zinc dust precipitates. These precipitates are leached to recover their Cd and Zn content. The final Zn bearing solutions contain relatively high Ni concentra- tions (20-100 mg/1) and are treated with DMG and then neutralized to pH 4.6-4.8. The pre- cipitate is filtered off and the solution returned to circuit. DMG consumption is about 200% of theo- retical requirement, and Ni removal is 80% complete overall.

Jan 1, 1977

By Fermino R

Reduction of waste oxides from steel plant operations was investigated in a laboratory tube furnace at different temperatures and furnace atmospheres. The results have shown that the waste oxide pellets are reduced rapidly to very high degrees of metallization irrespective of the furnace atmosphere and that the reduction is simultaneously accompanied by significant low- ering of the original impurities. It is shown, for example, that treatment at 1000¦C for 30 min. can reduce the Zn content from 0.98% to 0.0065% and K and Na contents from 0.19% and 0.76% respectively, to less than 0.01%. However, pellet strength at 1000¦C was low but this, as shown in the paper, can be very significantly improved by treatment at 1250¦C. The results indicate that the reduction of the waste oxide pellets of this investigation proceeds almost certainly by a chain reaction mechanism and that this principle could be advantageously extended to the reduction of iron ores and other oxides in general.

Jan 1, 1984

By P Mavros, K A. Matis, N K. Lazaridis

A large number of techniques are in use today to limit membrane fouling, among them certainly is air bubbling (which constitutes the transport medium in flotation) as applied in wastewater treatment; meanwhile, dispersed-air flotation is suitable as a pretreatment stage for microfiltration. The invented and investigated hybrid cell combines the advantages of both flotation and membrane separation, while overcoming their limitations, producing clean water from industrial wastewater. Metals recovery from dilute aqueous solutions is a promising application of this innovative hybrid process of flotation and microfiltration, further to solid/liquid separation. In this study, ceramic flat-sheet membrane modules were inserted inside a typical flotation cell in the laboratory tests, using multichannel geometry, combining flotation with microfiltration by submerged membranes; the latter requiring periodic backflushing. The specific objective was to apply this process for the efficient separation of effluents containing metal cations (here, zinc). The main examined parameters were: the initial metal concentration, flotation surfactant applied and air flowrate. The successful contribution of precipitate flotation was highlighted, while the observed metal removals were of the order of ~100 per cent.

Jan 1, 2005

By S Williams

The primary objective of most mining projects is to maximise the value delivered to the companyÆs shareholders. Achieving best practice performance and maintaining competitive advantage through low-cost production and high productivity is essential to achieving this aim. Benchmarking is an essential tool for the identification and implementation of best practice performance, and to realise continuous improvement by ensuring best practice becomes common practice. But to be successful, that is to deliver long-term value creation, benchmarking must be holistic and align operational performance with strategic intent. This paper outlines a rigorous and structured approach on how to conduct a successful benchmarking program that aligns operational performance with the businessÆs goals. Further it investigates the benefits that benchmarking can provide throughout the project life cycle and provides some key learnings from some of the worldÆs leading miners.

Jan 1, 2009

The introduction of legal certification of mine managers is a matter of history. It was introduced as part of legislation for mine safety. It has been said that such legislat- ion was written in blood. Like all legislation this legislation is divided into three sections; commands, obligations and sanctions. While legislation in all States on this subject is similar, the differences are great enough to have prompted the preparation of a Uniform Code by the Annual Conference of Chief Inspectors of Mines. This Uniform Code has not been adopted fully by any State to date. Legal certification of mine managers has made managers more aware of the requirements of the legislation covering their industry, legislation that reads as a summary on past accidents and methods of preventing them. While budding managers spend considerable' time in their early years in the preparation for certification, history has shown that the industry has benefited from their efforts. A better knowledge of the safety acts by the managers has produced safer operations, and a higher standard of management has raised the technical standards of mining operations to a stage where Australia can be proud.

Jan 1, 1980

By L Crew, S Jackson

A trial of an Adept Online Ore Sizer (OOS) was undertaken at the WMC Leinster Nickel Operation (LNO) in the first half of 2000. During this time the On Line Ore Sizer has been shown to be a robust and accurate instrument for measuring mill feed ore size. Data collected during the trial indicates significant variation in the F80 of the SAG mill feed. The effects of feed size on milling parameters such as mill weight, mill power draw and mill efficiency appears to be dependent on the ore blend treated. With some ore blends a weak positive correlation was found between ore size and mill weight and milling efficiency but with others no correlation is evident. It is believed that the OOS will become a vital piece of equipment in the future as LNO continues to optimises its milling circuit.

Jan 1, 2000