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By M H. Randell, J B. Haines

The Honeymoon Uranium Project comprises the Honeymoon Deposit,Goulds Dam Deposit and Yarramba Prospect in the Southern Lake Fromeregion, South Australia. Both the Yarramba Prospect and HoneymoonDeposit (which includes Honeymoon and East Kalkaroo orebodies) arelocated in the Yarramba Palaeovalley. The Goulds Dam Deposit is about75 km north west of Honeymoon, in the Billeroo Palaeovalley. Exploration for sediment-hosted uranium began in the area in the late1960s, culminating in the discovery of Honeymoon and Goulds Dam inthe early 1970s. In 1982, a 25 L/s demonstration plant was built atHoneymoon to confirm suitability for in situ leaching. The project was put on hold in 1983 due to changes in government policy. Southern Cross Resources Australia Pty Ltd acquired the project in mid 1997. Roll-front deposits form from a migrating geochemical cell, anadvancing reduction-oxidation interface between oxygenateduranium-bearing groundwater and its reduced aquifer host. The source of metal is uranium-anomalous granites, which were eroded fromsurrounding ranges. The weathered granites and resultant sediments are stripped of uranium by oxidised groundwaters, to form solutions carrying uranyl carbonate complexes. The solutions percolate down-slope through permeable sand zones until contacting a reduced environment where uranium precipitates. Uranium mineralisation occurs interstitially between and as thin coatings on sand grains, usually in the form of uraninite or coffinite. The palaeovalleys (previously termed palaeochannels) are incised intounderlying Cambrian/Precambrian basement rocks and filled withsemi-consolidated, largely un-cemented, Tertiary sediments of the Eyre Formation. The late Palaeocene to middle Eocene Eyre Formation is the basal unit of the Tertiary succession in the Callabonna Sub-basin of the Lake Eyre Basin. Further to the north, the Lake Eyre Basin overlies the Jurassic-Cretaceous Eromanga Basin, which comprises much of the Great Australian Basin. Eyre Formation sediments are in turn overlain by the late Tertiary Namba Formation and terrestrial Quaternary units. At Honeymoon, the Eyre Formation includes immature, pyritic,carbonaceous sands and gravels interbedded with lignite andkaolinite-illite-montmorillonite clays. It was deposited by braidedstreams during epeirogenic uplift of the Olary Ranges, accompanied bysubsidence of the Lake Eyre Basin. The Eyre Formation comprises aconsistent stratigraphy of interbedded sand and clay units that arecontinuous over the Honeymoon Deposit but with local variationindicating some hydrological connection between aquifers.In the Honeymoon orebody, uranium occurs within coarse-grained,pyritic sands where the basal sand pinches out between overlyingcarbonaceous clay and the southern palaeovalley slope. Its characteristics are typical of the well-developed, planar limb of a roll-front uranium deposit. Zonal changes related to the reduction-oxidation interfaces across the deposit are readily observable. The orebody extends for nearly 1000 m along the valley margin, is 400 m wide at its maximum and averages about 6 m in thickness. The East Kalkaroo orebody also lies near the southern margin of theYarramba Palaeovalley. It extends discontinuously for approximately 3.5 km and averages 200 m width, with significant uranium present in the Middle as well as the Basal Member. The Billeroo Palaeovalley extends northward for 40 km sub-parallel tothe western side of the Benagerie Ridge, is up to 5 km wide and hasgently dipping banks. Eyre Formation within the palaeovalley isconcealed beneath 90 m of Quaternary and Namba cover, isapproximately 40 m thick, and is sub-divided into three upward-finingunits, which are remarkably similar to the Yarramba Palaeovalleysequence.

Jan 1, 2001

By T P. Tafirenyika, K C. Corin, C T. O’Connor

There is a growing demand for copper driven by its applications in renewable energy and electric vehicles. Sulfide ores are an important source of copper. Flotation is a critical front-end process used to remove gangue minerals and concentrate the copper minerals. The electrochemical activity of sulfide minerals contributes to their overall activity in the flotation pulp. The mineral rest potential dictates how collectors interact with the mineral surface, and hence ultimately on the flotation response. Dissolved oxygen, (DO), pH, redox potential (Eh) and water composition and ionic strength are also significant in controlling flotation performance. The aim of this investigation was to determine the influence of the electrochemical environment both during milling and flotation on the flotation behaviour of bornite and chalcocite. For this investigation, the interactions of collector with bornite and chalcocite were studied using synthetic plant water (SPW1) and deionised water (DIW) at 5 different pH levels. Sodium isobutyl xanthate (SIBX) was used both in microflotation, collector adsorption and zeta potential tests.

Aug 24, 2022

One of the great attractions of academic life, for those who enjoy the opportunities of university teaching, is the continual contact with some of the most able young minds which each rising generation produces. So when I was asked to give a paper at t

Jan 1, 1994

Integrated chemical thermodynamic software and computerised databank systems have evolved over the last 15 years. The extent to which these systems have automated thermodynamic calculations relevant to extractive metallurgy is examined. The scope for further automation and the role of the expert consultant is discussed.

Jan 1, 1991

By Kuster D

Under humid conditions geochemical exploration for rare-metals is, at the reconnaissance level,usually carried out by stream sediment and soil sampling. As the secondary dispersion patterns are distinctly different in arid environ- ments, other exploration methods have to be applied (MATHEIS & KOSTER, 1985).

Jan 1, 1988

How many of you have felt tired and light-headed after standing or working in the sun or by the oppressive, hot, muggy conditions of an Australian summer? For those of you who have, you've experienced the minor effects of heat stress. Heat

Jan 1, 1994

This paper outlines some of the recent developments in Spiral Concentrator design, with particular reference to the range of Reichert spirals supplied by Mineral Deposits Limited, typical applications, and test or operating data, are also provided for the different series of spirals now available.

Jan 1, 1978

By Reeve JS

Heap leaching is a low capital cost alternative to conventional processing techniques for gold recovery from areas that contain small gold particles in a porous host rock.For successful heap leaching the ores to be leached must maintain good permeability after being stacked into heaps so that the leach solutions can percolate evenly through them.The presence of clays, slimes or excessive amounts of fines can hamper the flow of leach solutions causing channelling and producing dormant or unleached areas within the heaps. This results in unreasonably long leach periods and poor extractions. In extreme cases the clays or fines completely seal ore heaps, causing leach solutions to run off the sides of t'he heaps rather than penetrate the ore.The Northern Queensland Company uses the Agglomeration Heap Leach technique (AHL) to overcome the difficulties associated with clays or fines. This technique involves cementing the fines, by using readily available binders, into a rigid, porous network that greatly enhances uniform flow of cyanide leach solutions through the ore heaps.

Jan 1, 1986

The Liddell longwall equipment consists of 118 four leg supports, a shearer and armoured face conveyor of 170mm length. The equipment was supplied to Coal & Allied Operations Pty Limited (Coal and Allied) by Westfalia Australia Pty Limited (Westfalia). The project commenced as a feasibility study in 1983, a proposal was put to the board of directors in March 1984 and a specification distributed. Nine companies tendered for the supply of a longwall face and the supplier was selected from a short list of four companies. At the same time Coal & Allied examined the facilities at Liddell Colliery and decided to upgrade the conveyor belt system to cater for the high production from a longwall face. The surface facilities, transport system, water and electrical supplies to the colliery were also to be upgraded. During the twelve months to December 1985, the colliery was upgraded while the longwall equipment was being manufactured. The manufacturing process involved roof support testing, compatibility testing and finally a build up of 40m of longwall face

Jan 1, 1986

Information obtained from a reconciliation system provides fundamental indicators to an operations performance and is often neglected as a key performance indicator when developing a business plan or mining schedule. The cycle of exploration, ore definition, mining and processing within a company is constantly scrutinised both internally and externally as to the safety, environmental and financial performance of these activities with the operators judged on their performance on a periodic basis. However, it is not unusual for the reconciliation process to be given scant attention until a serious issue (usually a shortfall) occurs, at which point short-term solutions may be implemented which only serve to compound the original problem. A robust reconciliation system takes time to develop and implement initially and must continue to evolve with time. The best systems are those where all the stakeholders in the ultimate outcome are involved in the design and accept responsibility for the validity of their component inputs. Output from the reconciliation process can be utilised to fine-tune all aspects of an operation once the underlying issues leading to a particular result are understood.

Jan 1, 2002

By Oliveira JF

Thiourea is an alternative reagent for cyanide in gold leaching. The recovery of gold from acidic thiourea solutions by adsorption on activated carbon is based on methods similar to those applied for the extracting of gold from cyanide solutions, but the mechanism involved in the process is not completely understood. In the present work, studies were carried out to evaluate the adsorption of gold onto activated carbon. Experimental data showed good agreement with both the Freundlich and Langmuir isotherms. The adsorption of gold from acidic thiourea solutions proved to be an endothermic process, while the adsorption from cyanide is known to be exothermic. The isosteric heat of adsorption of -11.3 kcal/mol in the early stages of the adsorption is an indication of a process involving chemisorption. The effect of temperature was studied between 15¦C and 55¦C. An activation energy of 3.5 kcal/mol was determined by the Arrhenius plot, which indicates that the controlling step in the kinetics of adsorption is the diffusion onto the porous structure of the activated carbon.

Jan 1, 1993

The paper discusses the use of animated dynamic numerical simulations to support design and operational decisions in the mining industry. The basis of the simulations discussed is a queuing theory engine with added features that enable continuous processes to be included in simulations. This approach is well suited to the needs of the mining industry which has a mixture of discrete events interfaced to a variety of continuous processes via various forms of surge capacity. Examples are given of the benefits of animation in communicating concepts to those with limited domain knowledge and simulation as a tool that facilitates the sharing of understanding between the stake holders of a system. The analytical content of the paper addresses conflict for resources within systems, the constraints imposed by human and other types of resources, and the impact of external events. Examples are presented showing the use loop diagrams and Gantt charts in the recognition conflict, and its causes. and the use of utilisation logs to identify opportunities for cost reduction.

Jan 1, 2009

A major problem with many items of underground equipment is that they have either been converted or adapted from surface equipment, or that they have been designed and assembled in comfortable offices and factories with adequate lighting, specialised tools, and ample space. As soon as they are in use underground in cramped spaces maintenance frequently becomes difficult, parts are awkward to change, and a whole range of accidents can happen.Similarly, ingenious operators discover a whole range of uses for which the equipment was not designed, such as using a loader bucket for a work platform, or scaling backs with it.Design modifications of equipment and removal of hazardous components that can trap limbs is expensive when the dangers are discovered in operation, sometimes posthumously, and it is not surprising that workers compensation insurance premiums are high. The cheapest place to ensure that equipment is safe is in the design office, where the operator should be considered first, rather than being added to a purpose built machine as an afterthought.

Jan 1, 1992

By Lindbeck K

The mining industry in Western Australia is a large sector of the WA economy providing $12 billion (1993) of the export income for the State. Historically, mining in WA developed from traditional prospecting in the late-1880s leading to major underground operations by the turn of the century. Large open pits were developed in WA following World War II and became increasingly common since the gold boom of the 1980s. With the development of the open pits has been concomitant evolution of mining legislation, principally the Mining Acts of 1904 and 1978, which has been also accompanied by a practical evolution of the administrative system within the Department of Minerals and Energy. The mining industry has recognised the need for sound environmental management at mine sites, taking up the challenge and becoming a world leader in rehabilitation techniques. Any environmental management program in the industry has three stages: approval by government; management by the industry; and return to the State in an environmentally acceptable condition. The WA environmental requirements, procedures and industry performance in these three stages are discussed.

Jan 1, 1994

I am honoured, deeply honoured, that so distinguished a group has assembled to acknowledge the signifi- cance of the work of my Melbourne flotation research laboratory, to review progress since Principles of Flotation (Wark, 1938) was published, to highlight the present state of knowledge, and to point the way for future research. The flotation research which began in 1929 was sponsored by a group of mining companies2 at the instigation of Harry Hey of the Electrolytic Zinc Company of Australasia Limited. There were never more than three of us work- ing in rather cramped conditions in a laboratory made available by the Department of Chemistry at the Uni- versity of Melbourne, but what we lacked in space was more than offset by a freedom unparalleled in indus- trial research in Australia at that time. I pay special tribute to my first colleague, Alwyn Cox; to my wife who worked with us for several years; and to Keith Sutherland who followed Cox in 1936. They were my sole colleagues up to 1938 when Principles of Flo- tation (Wark, 1938) was published.

Jan 1, 1984

By Lewis IE

Copper-lead dross is a by-product of the refining of lead bullion produced by the Imper- ial Smelting Process. This dross contains some 27 percent copper, 50 percent lead, four percent zinc and one percent sulphur. An ammonium carb- onate leach at atmospheric temperature and pressure removed the copper from the dross while the lead zinc and precious metals remained in the leach residue for return to the smelter. The leach solution containing the copper was then purified by liquid-liquid ion exchange using LIX64N in a kerosene diluent. ("LIX" is the registered trade mark of a range of hydroxy oximes marketed by General Mills Inc.) The pilot plant had a capacity of 0.7 kg/h of CuSO4,5H20 and was operated for some fifty days on a two shift basis. Copper sulphate of excellent purity was produced, and the results obtained indicated that a copper recovery of ninety percent from the dross could be expected from a commercial installation.

Jan 1, 1975

The Argyle AK1 Pit has been operating and producing over 25 per cent of the worldÆs diamonds by volume for over 20 years. The mining boom in Western Australia is creating upward cost pressures to ArgyleÆs mining operation while the price received for its product remains flat in comparison to many other Western Australian commodities. This incongruity, which when combined with other circumstances such as the pit being close to the end of its mine life, a decline in head grades and a tightening in operational constraints caused by the pitÆs maturity, is causing the leadership team at the mine to utilise innovative strategies in order to ensure that the open pit continues to perform economically until its final closure in late 2010. The strategies that will be discussed in this paper are step change business improvement methods, localisation of the workforce, employment of Aboriginal people and the use of a clear and concise consultation process in order to provide certainty to a workforce working in a pit during boom times where pit closure is imminent.

Jan 1, 2007

By Tapponnier P

In North Vietnam, large ductile shear zones are observed along the Red river fault and the Dienbien fault. Left-lateral sense of the Red river shear zone is related to the direction of shortening E-W. NE dipping foliation planes is subvertical. Stretching lineation is subhorizontal ( 25¦). Left-lateral slip observed in the Oligocene Yansun granites demonstrates the major tectonic phase in Neogene, The stress field established from microfaults observed in triassic limestones, Oligocene granites and Neogene Conglomerates. Measurements of striations on fault mirors are used for calculating the stress tensor and for separating tectonic phases. Two tectonic phases in tertiary are separated : first tectonic phase related to the compressive direction E-W corresponds to the major tectonic phase represented by NW left-lateral shear zone. Second phase having the compressive direction N-S associated with the right-lateral movement of the Red-river fault zone opening of the Eastern sea and the Red-river and the Red-river delta is associated with the left-lateral movement along the Red-river.

Jan 1, 1990

A sample of tailings from a local, low grade (less than 2g/t) tailings dump was investigated for gold recovery. The tailings were very fine, with 90 per cent passing 30¦m and almost 60 per cent passing 10¦m. Tabling the coarse product from classification using a cyclone proved unsuccessful, with low recoveries being obtained due to high gold losses in the slime streams. Gold recovery by cyanide leaching was quite rapid, with recoveries of 85-90% being obtained in five hours. Lime and cyanide consumptions were 3 g/t and 0.1 kg/t respectively. Gold loading onto carbon was inhbited by the presence of the large amount of fines, so heap and vat leaching should be considered where the gold is recovered from a clear pregnant solution. Settling tests were conducted on tailings. It was observed that the addition of at least 3 kg/t lime or 0.4 kgh nonionic flocculant was necessary to promote settling of the tailings to generate a clear supernatant for gold and water recovery.

Jan 1, 1991

Economic and environmental pressures are shifting the world balance of titanium dioxide production away from sulphate based. manufacture towards the more cost effective and cleaner chloride route. In the chloride process for titanium dioxide pigment manufacture, TiOz and other metal oxides in the feed ore are reacted at high temperature with chlorine in the presence of carbon. These gases are cooled after they leave the reaction zone, upon which solid contaminants precipitate and are substantially removed. The liquid titanium tetrachloride is purified by distillation before again being vaporised and interacting with hot oxygen to form pigmentary titanium dioxide and regenerate chlorine for recycle. The base pigment is wet milled, surface treated (by coating with hydrous oxides of silica, alumina and others) and redispersed before packaging. Optical properties of TiO2 pigments are reviewed and the role of refractive index and particle size explained in brief. Pigment related factors affecting the opacity, colour, undertone, gloss and durability of coatings are examined with respect to manufacturing requirements. The superior performance of chloride based pigments is briefly reviewed.

Jan 1, 1991