Search Documents

By C Wu, H Chen

"An EXTENDED ABSTRACT is available for download. A full-length paper was not prepared for this presentation.The Halasu porphyry copper belt, located in the East Junggar basin bounded by Chinese Altay to the north and the Tianshan mountains to the south in the Central Asian Orogenic Belt, is one of the major porphyry copper belts in Xinjiang province, north-west China. Combined with previous studies in this area, the magmatism can be divided into three periods: pre-mineralisation activity of 390 Ma syn-mineralisation activity of 380–370 Ma post-mineralisation activity of 360–330 Ma.Through the comparison of zircon chemistry from ore-bearing and barren syn-mineralisation intrusions, negative correlation was identified between Ti-in-zircon temperatures and oxygen fugacity, corresponding to the fact that late-stage syn-mineralisation granitoids contain high water content, high oxygen fugacity and low temperatures with higher mineralisation potential. In addition, the relative low initial 87Sr/86Sr ratios, high eHf(t) and eNd(t) values and mantle Pb isotope characteristics in this study support that the magma forming these intrusions was probably derived from juvenile crust generated during subduction-accretionary processes.CITATION:Wu, C and Chen, H, 2015. Zircon trace elements and Sr-Nd-Pb-Hf isotope systematic of the Halasu porphyry Cu belt, north-east Xinjiang, China, in Proceedings PACRIM 2015 Congress, pp 637–640 (The Australasian Institute of Mining and Metallurgy: Melbourne)."

Mar 18, 2015

By R J. Thompson

In truck-based hauling systems, the mine haul road network is a critical and vital component of the production process. As such, underperformance of a haul road will impact immediately on mine productivity and costs. Operations safety, productivity and equipment longevity are all dependent on well-designed, constructed and maintained haul roads. With the advent of autonomous haul trucks, the haul road itself becomes all the more critical to the success of these type of operations; not only in relation to mine operators requirements for safer and more efficient and predictable haulage systems, but also in response to autonomous truck manufacturers’ requirements for a more predictable and controlled operating environment. This paper presents a brief summary of the state-of-the-art in surface mine road design and then proceeds to examine the design and technological challenges associated providing a safe, predictable and affordable road for autonomous mine haul trucks. The paper serves as a basis for evaluating the contributions that enhancements in road design and management can deliver to autonomous mining operations, an initiative that also has scope for adoption within the operating life of many mines, haul roads and haul trucks.

Nov 22, 2011

The basic methods to remove material from underground mines are to: convey continuously, batch in trucks, or batch in a shaft hoisting system. A critical aspect in shaft hoisting is accurately batch loading the conveyance or skip. During the 20th century, the almost universally accepted method of loading was via a measuring flask. A measured quantity of material was filled into the flask as the conveyance traveled through the shaft and then, when the conveyance arrived at the loading position, it was ædumpedÆ into the skip for hoisting. Two skip loading conveyor systems have been developed in Australia: BHP BillitonÆs Cannington Hoisting System, installed in 1996, is believed to be the first conveyor loading system designed for two skips. Two parallel conveyors were installed with a two-way gate controlling feed onto each belt. Cannington was ideally suited to conveyor loading as the very high ore density and relatively low production rate required a relatively small volumetric storage capacity on the weighed belt. Newcrest MiningÆs Telfer Hoisting System, which is to be commissioned in 2005, consists of a single slewing conveyor loading each skip with 32 tonnes of ore. The development of this system eliminates the two-way transfer, improves the accessibility and minimises the excavation required. While every hoisting system must be considered on its merits, conveyor loading offers significant advantages to the Mining Industry in the 21st century.

Jan 1, 2005

Pyrrhotite is the predominant gangue mineral at Renison comprising about 60 percent of the sulphides in an average ore blend. It exists as two crystal structures - monoclinic and hexagonal. Monoclinic pyrrhotite is the slowest floating of all minerals but is ferromagnetic and hence recoverable more efficiently by low intensity magnetic wet drum separators than flotation. This paper discusses the installation and commissioning of four 0.915 m x 3.0 m, 0.1 Tesla permanent magnet, wet drum separators prior to sulphide roughing flotation. Planned circuit and process control modifications to better accommodate magnetic separation into Renison's flowsheet will be Discussed.

Jan 1, 1991

A simulation of the fluid flow, minera- logical and chemical aspects of in situ leaching is being developed for application to the recovery of metals from unbroken, naturally jointed rock. The fluid flow aspect has been developed. The rock is assumed to have a double-fracture property. A major joint set is responsible for bulk flow of solution, while a minor joint set, intersecting with the major set, allows the solution to contact the reactive minerals. The two-dimensional fluid flow through the major joint set is analysed by a streamline model for a particular well pattern. The other important components of the model are described briefly.

Jan 1, 1984

Geological. engineering is a field of engineering practice concerned with design and construction of excavations and structures in soil and rock masses. The role of geological engineering in mining practice is defined in this paper, and the scope of the various disciplines in engineering science and geoscience which support geo-engineering research is discussed. The current national research capacity in geo-engineering is considered, and current and future needs for geo-engineering research for mining practice are proposed. Education programmes to sustain the proposed level of research and its industrial implementation are Suggested.

Jan 1, 1986

By L P. Gray

"From paving the way in gaining approval for the first metalliferous in-pit tailings storage facility (TSF) in Victoria, to developing a deposition methodology to optimise the storage capacity and provide a final rehabilitated surface which replicates the premining topography, in-pit tailings storage has proven not only to be a cost-effective means for tailings management at Fosterville Gold Mine, but also one which provides significant economic, social and environmental benefits. Coupled with ongoing raising of the existing above ground TSF and commissioning of a new above ground TSF, Fosterville Gold Mine have to date effectively used three open pits for in-pit tailings storage, with one of the pits currently progressing through the capping and vegetation establishment phases of closure.This paper presents the process adopted by Fosterville Gold Mine in their flotation tailings management, from design and operational phases through to rehabilitation implementation. Included within the paper are challenges which have arisen during the process, and a discussion on principals behind the designs and lessons learnt during operation of the facilities.Citation:Gray, L P, 2016. Full Cycle Tailings Management at Fosterville Gold Mine, in Proceedings 13th AusIMM Mill Operators’ Conference 2016, pp 369–378 (The Australasian Institute of Mining and Metallurgy: Melbourne)."

Oct 10, 2016

By Golab K, Partridge AC, Fletcher CAJ, Holtham P

Spiral concentrators are used globally in the fine coal processing industry to segregate particles, by gravitation, on the basis of density and size. Consisting of an open trough that twists vertically downwards about a central axis, a slurry mix of particles and water is fed to the top of the concentrator. Particles are then separated radially as they gravitate downward. Since their introduction to Australia in the 1940's, the generic design has evolved largely by laboratory trial-and-error investigations of different prototypes. However, this approach has proven expensive and optimal designs have not been necessarily developed. Accordingly, Computational Fluid Dynamics (CFD) analysis has been used recently as an alternative method of investigation, to assume as is envisaged, a role in the design process. To date, CFD models have progressed to simulations of turbulent fluid flow on current production spiral designs, and are continuing to be adapted for inclusion of particles at realistic feed concentrations. To be able to use the models confidently however, laboratory experiments must also be performed to validate the predictions during the development stage. This paper reports the current findings of an ongoing CFD and experimental program applied to one spiral unit. Satisfactory quantitative agreement has been achieved for the fluid and particulate flow characteristics, and although further validations are appropriate, the model already possesses significant potential for use as a reliable predictive design tool.

Jan 1, 1998

By Nguyen V. V

The development of structural defects in the overburden material immediately behind a production blast was studied using surface and subsurface techniques. A significant increase in vertical and horizontal fracture intensity was recorded. The extent of fracturing into the highwall appeared to be dependent on the structural and petrologic characteristics of the various lithological units and the relative position of the explosive charges. A shallow zone of disruption to a depth of 10 m and extending to around 30 m from the newly formed highwall crest was recorded. Horizontal fractures in lower units of the overburden sequence were recorded at distances up to 50 m from the new highwall Face.

Jan 1, 1981

By J Brisebois

The derelict Lake George Mine is located at Captains Flat in NSW, acommunity of approximately 450, which lies some 43 km southeast ofQueanbeyan. It straddles the Molonglo River, which flows toQueanbeyan and thence the nationÆs capital, Canberra. Catastrophictailings dam failures in 1939 and again in 1943 resulted in the transportand dispersion of thousands of tonnes of sulfidic wastes downstream,with terminal settling in Lake Burley Griffin, in Canberra. The mine wasclosed in 1962, and major rehabilitation in 1996 - 1997 addressed the riskof further collapses, and reduced water flow into the underground mine.Nevertheless, acid mine drainage from the mine, and seepages ofcontaminated water from the capped tailings dumps continue to pollutethe Molonglo River for some 30 km downstream.Environmentally, the highest contributor to the total contaminant loadof the river is the Main Adit Spring. This was shown to be a constantgroundwater-driven acidic flow, with contaminant generation resultingalmost entirely from the ingress of gaseous oxygen into the undergroundworkings. Long term remediation may be possible at source, by pumpingreducing gases into the sealed mine, but the probability of thistechnology succeeding to the required degree is yet to be demonstrated. For at least the medium term, treatment of contaminated water flow(s)will be required to achieve any of the water quality targets that may beapplicable to the river. Three methodologies were short listed, but anumber of strategic uncertainties remain, which the NSW Derelict MinesProgram will address. Future risk arising from long-term contaminantrelease by the treatment wastes must be considered. Appropriate data,and realistic long-term performance parameters regarding the relativestabilities of water treatment sludges are scarce, and make properevaluation of competing technologies problematic.

Jan 1, 2003

By Stanton G

The Department of Mapping and Surveying (DMS), the Australian Key Centre in Land Information Studies (AKCLIS), the Department of Industry Development (DID) and the State Government Computer Centre (SGCC) are testing a regional information network in northern Queensland. Several study sites have been chosen by different groups of participants. The members of each common-interest group share their data for the site. They can also access datasets supplied by other organisations that are not directly involved in the particular study being undertaken. The participants include state government departments, local authorities, fed- eral organisations and the private sector. The participants communicate with computer systems in Brisbane via Q-Net. Q-Net is a pilot State government tele- communications network, established by the Department of Industry Development. Q-Net uses the communications sat- ellite AUSSAT 1 as the primary instrument of data transfer. The Q-Net network is a star system, with a Master Earth Station in Brisbane acting as a hub for radial earth stations, located throughout Queensland.

Jan 1, 1987

By Walton M. C

A combination of flotation and smelting technologies is proposed as a cost-effective means to maximise the revenue of base metal operations. The proposed treatment route breaks the grade - recovery nexus associated with the treatment of ores exhibiting difficult mineralogy in conventional plants. Aspects of the two technologies are reviewed and typical capital and operating costs presented. A significant improvement in revenue is demonstrated in a worked example, where a copper-lead-zinc operation is examined in terms of the conventional and proposed treatment options. For the selected ore, the net smelter return per tonne of mill feed improved 57 per cent, from US$89.70 to US$141.10 with the proposed treatment option. This represents an additional US$51.4 million in annual revenue. Metallurgical operating costs increased by US$20.12 per tonne of mill feed for an incremental capital requirement of US$30.3 million for an existing operation.

Jan 1, 1992

By Watt JS

The ash content of coal can be determined using radioisotope X-ray techniques. A number of overseas applications of X-ray techniques are described; however these suffer from the disadvantage of either not compensating for iron variations or, if compensation is used, using X-rays of low penetration with consequent sampling difficulties. Current Australian Atomic Energy Commiss- ion (AAEC) research on X-ray techniques is aimed at overcoming the limitations of these methods. The AAEC method involves making measurements proportional to mass absorption coefficients of X-rays in coal at two energies. Calculations and experiments with X-rays up to 35 keV have shown that ash content can be determined to about 1 wt.%. This work is being extended to higher X-ray energies to enable the technique to be used directly on a conveyor belt or in a hopper. Neutron techniques can be used to measure the concentration of specific elements such as carbon, hydrogen and silicon in coal. Their con- centration is correlated to the coal parameters of interest. Methods of moisture determination based on hydrogen measurement and ash determina- tion based on silicon and aluminium measurement are described. Energy content can be determined accurate- ly by analysing the carbon content of coal

Jan 1, 1978

Universities have had a long history in the education of geology graduates, Analysis of this history reveals a record of success, as judged on a world basis. However there have been significant changes in the last 20 years that have impacted on the ability of universities to continue to provide their traditional style of geology education. These changes have increased in the last 10 years. In the teaching side, there has been a change in expectations. Additionally the increasing workload decreases the value of each academic to perform the tasks needed by the new education. In the area of research, the funds provided have continued to decline, in both real and absolute terms, and it is now necessary for universities to seek out funds to pay for their postgraduate research. Additionally, the universities have slipped into the error of what cahn only be termed "academic incest", and research student mobility has decreased to an undesirable level, stifling initiative and new ideas in a number of cases, The only solution is for Government monies to be "directed" - ie that the postgraduate student must leave his or her original university in order to receifve the research stipend/scholarship. On the government front, the government and its agencies have not adequately analysed and recognised the need for the redirection of education and research funds into the needy areas of science and technology, especially those that related to the minerals area.

Jan 1, 1986

By S J. Loach

F-Series reconciliations are formal comparisons of estimates and measurements of ore quantity and quality made at pre-determined points along the mining value chain. F1 is the ratio of ‘Depleted Grade Control Ore/Depleted Long-term Model Ore’ and validates the models upon which Resource and Reserve statements are based. F2 is the ratio of ‘Produced Tonnes and Grade/Depleted Grade Control Ore (-) Changes in Pre-Crusher Stockpiles’ and validates that the ore tonnes and grade delineated in the pit are being accurately extracted and correctly delivered to the processing plant. These factors provide important corporate assurance for a mining company by providing quantitative feedback on model-predicted tonnes and block grade estimates. Since 2009, BHPs Western Australian Iron Ore F-Series reconciliations have been calculated in a single, centralised sequel-server database. This software routinely collates data regarding mineral resource block model depletions, grade control model depletions, pre-crusher stockpile inventories and production tonnes and grade measurements and then calculates F-Series factors for both tonnes and product quality. This paper will present case studies where reconciliation factors were used to identify improvement opportunities leading to projects that improved our models and subsequent forecasts of production tonnes and quality. In addition, it will show how reconciliation factors are tools that monitor control during periods of rapid change and provide feedback on the effectiveness of improvement projects.

Sep 18, 2023

This work was instituted to investigate the microscopic structure of brown coals by means of microtome sections cut from them. It was found to be essential to impregnate the coal with some material prior to cutting, because of its powdery and crumbly nature. Of a number of impregnating materials tried, e.g., glycerine gum, gelatine, by far the most satisfactory was paraffin wax. Samples of brown coals for section cutting must be moist. When obtained, they should be put immediately into air-tight tins, and, if they are not to be used for some time, it is desirable to keep them under water containing a small amount of formalin. If the sample is allowed to dry in air, it becomes too hard to be cut. It cannot be softened again even by prolonged soaking in water.PREPARATION OF COALSmall rectangular, blocks were cut from the sample with a chisel and a strong scalpel. The largest block prepared was 3·2 x 2·5 x 0·6 cm. The faces of the block from which sections were to be cut were approximately levelled before treatment. The block was then painted carefully on all sides with two coats of warm aqueous agar, approximately 2 %. This prevented crumbling and breakage of the block during treatment. When the agar was set, the block was placed in water, and all the air removed with a vacuum pump. The water was replaced first by alcohol, then by chloroform, by the usual step transference of a series of liquids, in each of which the block was placed for 24 hours: Ethanol %, 10, 20, 30, 50, 70, 85, 95, 100 (three changes); Ethanol-chloroform, 3: 1, 1: 1, 1 : 3, chloroform pure (three changes) '. The blocks were then embedded in paraffin of melting point 56-58°C. Fresh...

Jan 1, 1947

By A G. Grice

Surface disposal of mining processing wastes is usually perceived as an undesirable consequence of meeting societyÆs needs for metals and minerals. Environmental disasters associated with the discharge or storage of such wastes, though infrequent, can have very damaging consequences for the environment and the industry. Reducing or eliminating the potential for such events may be achieved by placing some or all of these processing wastes back into the voids created by the mining operations. Processing operations may limit or enhance the opportunities for using tailings and other waste products as a backfill material. Backfilling is a truly multi-disciplinary process and requires the informed involvement of mining, metallurgical, engineering and environmental specialists. This paper describes the range of fill types currently being used in Australian mines, particularly those utilising processing wastes as constituents. It focuses on how processing operations can affect the suitability of these materials for the various types of fill, the resulting fill properties, fill performance and costs.

Jan 1, 2002

By I KylmSkorpi, H Mansikkaviita

The traditional direct-heated drying process has been replaced by the steam drying process in non-ferrous metal smelters, where steam is available from waste heat boilers. Many recent projects have selected Kumera Steam Dryers in equipping a new production line or modifying an old production line. The industrial performance of the steam dryers has shown significant energy saving and emission reduction. The steam dryers have been operated at high availability and long maintenance interval. As the process principle of Kumera Steam Dryer is different from other equipment, the set-up for steam dryer plants is configured to fit the smelter site and operation conditions to achieve optimal performance. This article discusses the equipment involved in the steam drying process and their combination options.

Jan 1, 2008

By Morris B. J

Soil air samples taken from the top one metre of the soil profile, were measured for C02 and 02 using portable field analysers at a number of sites of known sulphide mineralisation in South Australia. Carbon dioxide anomalies were detected over actively oxidising sulphides during autumn and winter following recent rainfall. Anomalies were not detected where no oxidation was occurring, where seasonal conditions had been very dry, or where the sulphur content of the ore was low (

Jan 1, 1993

The Iron Prince orebody occurs within the Lower Middleback Jaspilite Horizon of the Middleback Group and consists of hematite within host rocks of jaspilites and schists. The ore was probably the product of leaching of silica from jaspilites and replacement by iron, concentrations occurring in suitable structural traps. The narrowness and the presence of extensive dolerite amphibolite dykes within the orebody make it essential to operate a grade control programme in advance of the faces. Information from drilling is drawn up on bench plans, step plans and impurity overlays, and these serve both in day to day production planning and in long term planning. Mining is done selectively by open-pit methods and blending conducted by keeping at least three faces of different grades of ore open at any one time. No stock piles of ore are kept for blending, but contact ore, contaminated ore and enriched material are dumped for later beneficiation.

Jan 1, 1971