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By Jifan X, Yongyu W, Liangjing L

Shallow interception of groundwater is a special dewa- tering form in the specific geological and hydrogeological conditions. It has an economic and technical effect. The roof of the Fankou Lead-zinc deposit is the Hutianqun aquifer made up of the limestone of the upper Carboniferous system. - A "water-bearing basin" is surrounded by the aquifuge and the aquitard below ¦0 m level at the Shiling Hill section in the Hutianqun aquifer. Based on the natural conditions, an interception gallery is excavated at -40 m level out of "the water- bearing basin", the other gallery excavated at ¦0 m level in the poor water-bearing zone of the Jinxing Hill. During 20 years of experience, the better interception effects have been gained.

Jan 1, 1988

By J Herbertson

æZero waste steel making productionÆ has already been the subject of several studies and also the successful result of some companies. Regarding waste and by-products, slags are the largest in terms of weight, although among the least hazardous. All steelmakers around the world are presently looking into profitable solutions, according to their local conditions: environment constraints, available markets, and mode of operation. Today the major technical methods of slag value capture include different levels of magnetic separation and screening to remove entrained steel, for production of aggregate in civil works. A survey of different retrieval processes shows that pyrometallurgical processing of steelmaking slags will increase the recovery ratio of iron and other metals. In the process, the remaining part of the material, a mixture of metallic oxides, can be easily transformed into hydraulic binder such as cement. Can steelmakers consider the slag as a co-product, and not only a waste or by-product? The ability of pyrometallurgical processes to treat other wastes and by-products generated in the steelplant is an opportunity for the steelmakers to reach the æzero waste productionÆ status. A technical survey of the experiences and possible solutions of pyrometallurgical processing is presented as well as technical descriptions of technological, economical and profitability analysis in relation with foreseeable markets.

Jan 1, 2002

By Lowder G. G, Cooper R. S, Radke F, Watmuff I. G

During the past five years Amdel has in vestigated metallurgically and mineralogically most of the Western Australian nickel sulphide ores. The mineralogical work has been carried out primarily to assist the metallurgical stud- ies and this paper reviews the application of mineralogical techniques to such ores to obtain information of direct use to the process met- allurgist. The techniques are described briefly and results are given of various in- vestigations of head samples, concentrates and tailings.. It is demonstrated that mineral- ogy has an important role to play in the optim- ization of nickel processing operations.

Jan 1, 1973

By Q Zhou, Y Ma, J Zhu, R L. Frost, P Yuan

A series of organoclays with different surfactant arrangements were prepared by ion exchange. The resulting organoclays were investigated using a combination of characterisation techniques, including X-ray diffraction (XRD), Fourier transform infrared spectroscopy (FTIR), thermogravimetric measurement (TG) and N2 adsorption-desorption. In the present study, the pores within the organoclays were discussed on the basis of the micro- structural parameters, including BET-N2 surface area, pore volume, pore size, surfactant loading and distribution. The results show that both BET-N2 surface area and pore volume decrease from low to high packing density of the surfactant as the average pore size increases. Two basic organoclay models were proposed for hexadecyltrimethyl- ammonium bromide (HDTMAB) modified montmorillonites: 1. the surfactant mainly occupied the clay interlayer, and2. both the clay interlayer space and external surface were modified by surfactant. This study demonstrates that the pore structure of the resulting organoclays has a significant influence on the sorption efficiency and mechanism of p-nitrophenol onto the organoclays.

Jan 1, 2008

A geostatistical study is made of the drilling results available one stage prior to the present for a tabular deposit. The results show that the blocks required by the mining engineers could have been assessed by the earlier drilling grid with an accuracy significantly better than that obtained by applying conventional methods at the present stage.

Jan 1, 1976

The city of Kalgoorlie-Boulder is located 595 kilometres east of Perth in Western Australia, and has a population of just over 30 000. Western Australia's third largest city lies on one of the richest goldfields in the world, with over 45 million ounce

Jan 1, 1998

Cut and fillstoping using hydraulically placed mill tailings has become an essential feature of stoping operations in Kalgoorlie. ' Approximately 30 per cent of the total production is currently mined by this method. Fill is prepared by thickening or cycloning and is gravitated or pumped underground. The average pulp density is 70 per cent solids by weight, Recent cost reducing innovations are the use of steel passes, corrugated iron manways, polythene film sealing, and the replacing of vertical cement lined pipes with boreholes. TTTTTI rvr T Trim r l1TT

Jan 1, 1964

In many metal mines in China,the 70B2 series of fans has been used for main fans for a long time.These fans generate higher static pressures than are required for the relatively high equivalent orifices of the ventilation systems of many of the mines. As a consequence, their running efficiency is common only around 30%. The loss of power is significant.

Jan 1, 1988

In the first half of this century a mining industry was developed in Indonesia under Dutch colonial rule. World War II and the subsequent struggle for independence resulted in the destruction of most of the infras- tructure and much of the data. After independence, restrictions on for- eign investment and internal turmoil prevented re-establishment of a viable mining industry until the formation of the present Government after 1965 and the enactment of sound laws in 1967 to encourage foreign investment. Rebirth of the mining industry was followed initially by slow growth, but in the 1980's, spurred by the worldwide interest in gold, Indonesia has become the focus of an intense exploration boom for gold and other precious metals. 103 Contracts of Work for gold have been awarded since 1985 with Australian companies being the most predominant. Since 1985 three new gold operations have been commissioned and another two are nearing completion. Several more are undergoing feasi- bility studies. There is reason to predict that Indonesian gold produc- tion will grow to place the country in the ranks of significant producers during the 1990's.

Jan 1, 1988

The reasons for selecting two stage pebble milling in preference to conventional methods of grinding are discussed. Commissioning of the first section was completed in October, 1969. Improvements in both the operating and engineering aspects were then incorporated in the section commiss ioned in March, 1971.

Jan 1, 1975

Water is a key resource input to copper heap leach operations in both quality and quantity. A number of recent developments in analysis of the technology have shown that water consumption can be optimised. The leach consumption has been generally considered in terms of minimisation of the evaporative loss by changing the application method (drippers or wobblers). Modelling of the irrigation effects on leach rate has shown that the poorer surface coverage from drippers has an adverse effect on the leach extraction rate. This is particularly evident in the early part of the leach. The use of different irrigation systems during alternate parts of the leach cycle can have benefits in minimising the water consumption without an unacceptable outcome from extended extraction times. By combining the leach rate effect with the evaporative loss estimates, an economic decision matrix can be generated to allow the operator to select an appropriate leach irrigation strategy, combining both irrigation delivery and irrigation rate. In the SX-EW plant, the total quantity of EW bleed and SX scrub stage bleed (both for iron control) can be reduced to an absolute minimum. The economic minimum may be different depending on the cost of producing the high-quality water used to replace the bleed streams. Adjustment of the SX process, in particular use of multiple entrainment control steps, can provide significant reductions in the total bleed and make up requirements.

Jan 1, 2003

By Rolley P

In the course of reviewing grade control practices at the Marvel Loch gold mine in Western Australia in 1992, FSSI Consultants developed and implemented a novel approach to ore selection using a method to maximise financial return (the MP method*). The approach was based on improved grade control sampling and an ore selection method which directly incorporates both a measure of the uncertainty in knowing the true grade of selection units in the definition of ore, as well as the operating cost and revenue parameters of the mining operation. During the past four years, FSSI Consultants have evaluated and refined the use of this approach and have implemented customised variations of the MP method at seven gold mines and a gold-copper mine in Australia. The previous methods of ore selection at most of these operations were based mainly on polygonal - sectional methods of grade estimation. At all of the sites where grade control optimisation has been given a fair trial over several months of production, the use of the MP method has been consistently rewarding to the mining operations. The benefits include increased run of mine ore stockpiles and low-grade stockpiles and decreased fluctuation in the production grade. Most operations have also benefited from a consistent ability to improve production grade through high-grading of the increased ore production. The increase in ore production has the logical benefit of reducing stripping ratios, increasing mine profitability and mine life.

Jan 1, 1997

By Robinson BW, Walker RK

Using a new highly stable automated electron microprobe analyser, detection limits for gold in arsenopyrite have been improved. Using the AuLA emission tine at 40kV and 500nA, a limit of approximately 10gpt is attained in 10- lSmins. Some unusual features of the background need to be taken into account. Several ores containing different levels of gold in arsenopyrite have been examined, and it has been shown that gold is not evenly distributed between grains (some may contain more than 1%, invisible optically), and that the grains containing gold are often zoned. Gold may be released from the arsenopy rite by weathering or by heating in an inert or slightly oxidising atmosphere.

Jan 1, 1989

Managing project exposure and risk has numerous viewpoints, including those of engineers, owners, bankers and insurers. Fewer stakeholders are involved in early stages, though with wider risk management techniques and tools available. The costs and sometimes benefits of the occurrence of risk and uncertainty have different contingent outcomes for different stakeholders. For some, the impact of risk outcomes can be mitigated or managed. Some sectors and stakeholders can manage resources project risks more completely, by choice or by externally imposed forces, opportunities and constraints. The core to resources project risk management lies in the identification and analysis of project risks, the examination of project management risk options and alternatives, and the determination of which risks are able to be controlled, managed or laid off to third parties. Without prior risk identification and knowledge, the wildcard of previously unidentified or unconsidered project risk impact has the potential for fatal impact to one or more stakeholders. A range of case studies is reviewed, from exploration projects to development and operating projects, with relevant learning experiences, from the risk management lessons available from the oil and gas sector as well as the mining sector. For many cases, the emphasis focuses on the risk analysis modus operandi and on risk management and risk mitigation techniques that can be and in some cases have recently been implemented for resources project and related debt, capital markets and equity project fundings.

Jan 1, 2003

As part of a prefeasibility study being undertaken by Newcrest Mining Limited, the Cadia East Implementation Team has developed an access decline to the proposed underground operation. This paper describes new technologies that have been employed in this development, which include: high frequency drifters that have penetration rates one and a half times that of competitors, ensuring minimal increase in drill time, despite rounds greater than 5.5 m;automated drilling used in conjunction with laser navigation and face pattern design software, which facilitates exact positioning of hole collars, lengths and lookouts for accuracy and repeatability; andemulsion charging that reduces manual handling; has variable string loading capabilities, via its hose retraction system, for perimeter control and reduced fume characteristics. A Six Sigma improvement process was used to support the system change undertaken and demonstrated that development rates improved 60 per cent above the comparable single heading benchmark.

Jan 1, 2008

Where tunnel rounds are based on the burn cut, faster advance could often be achieved by increasing blasthole diameter from (the conventional)

Jan 1, 1981

Recent exploratory work has greatly enlarged our knowledge of the geology of the sedimentary basins of Western Australia. The most pros-pective of these for oil explorati on are believed to be the Canning, Carnarvon, 'and Perth Basins.The search for oil. in, the Canning Basin has fora the most part been concentrated in" the western part, where four main structural units are now recognized - the Lennard Shelf, Fitzroy Trough, Jurgurra Terrace, and-South Cariizin.g Basin. Of these the Leonard Shelf may. be the'most prospective. The principal objective on the Shelf is the Devonian sequence, which in-cludes well'developed reef complexes. The Lower Carboniferous is regarded., as a further objective, as it contained small quantities of oil in theMeda No. I well.In the. Carnarvon Basin most explorati on has been conducted in the coastal belt of'Tertiary folding, especially in the Cape Range-Rough Range area. -The discovery of oil in the first test well. drilled.in the-basin - Rough Range no. 1 - raised great hopes, for the quick discovery of a ecmuercial field. However the other wells on Rough Range have been dry, and no discoveries have-been made in the-wells drilled on other anticlines.in the basin.

Jan 1, 1962

Geomorphology is one of the most basic elements in geographic enviroments. Geomorphological mapping is significant in the spatial distribution of representing land form and understanding various features of geomorphology. Geomorphological mapping began very early in China, as the map, showing conekarst(karst pinnacles) of Juiyishan, Hunan province, it was drawn in 168B.C., which was excavated from Han tomb. Mawangdui, Changsha. Its original idea of map-making is rather similar to that of modern map and could undoutedly be the oldest map of tropical karst discovered in the world.Before liberation, landform mapping was done piecemeally and only a small number of maps were prepared by a few editor as insets.

Jan 1, 1990

The Musselwhite mine, located in northwestern Ontario, Canada, has been an underground narrow-vein gold producer since the spring of 1997. As an exploration project at the feasibility stage, much effort was undertaken to generate a geostatistical resource model that would integrate the orebodyÆs geological features, as well as the controls on mineralisation. Today as an operating mine producing over 200 000 ounces of gold per year, reconciliation studies of the tonnes and grades treated at the mill, with the feasibility model, for longer time periods, and with the grade control models, for shorter time periods, show results that are in good agreement. It was clearly demonstrated with the reconciliation to production, that the key to good reconciliation remains in the proper selection and application of the geological resource estimation method. The application of a grade interpolation technique capable of capturing threedimensionally pertinent geological features, as well as accounting for spatial grade continuity, proved to be successful in the predictability of tonnage and grade at the Musselwhite mine. Along with good mine practices, this approach, which was carried through to the operation, has produced excellent reconciliation results. The ongoing reconciliation studies at Musselwhite allow for a constant revision of the grade estimation strategy. In return, this optimisation process adds value by raising the accuracy level of production expectations. As this is an evolving practice at the mine site, further implementation developments are recommended to integrate these reconciliation procedures on a more regular basis.

Jan 1, 2002

By Mousset-Jones P, McPherson M. J

This paper explains and discusses a computer program developed to deter- mine the optimum combination of fan pressures that will give a required distribution of airflows in a mine ven- tilation system. The program is based on an existing simulator, VNETPC and two experimentally developed relationships: (1) linearity between fan pressures and added regulator resistances and (2) a non- linear convex function relating the system air power and the fan operating Pressures.

Jan 1, 1988