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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 Golledge P

Safety legislation has a long history and widespread application, but how can one test its effectiveness? One way is to examine safety statistics. Another way is to compare the legislation with principles of good safety practice. Mine safety legislation contains many features that are widely accepted, and these should be examined critically to determine their importance. Uniform legislation and revision of legislation should be considered. INTRODUCTION

Jan 1, 1975

During 1979 the writer had the privilege of interviewing about 50 people with varying degrees of involvement in the industrial arena and all of them in one way and another, had a part to play in the huge and intricate saga of Australian employee relations. They fell into the following' categories Industrial Relations Officers/Managers Academics Politicians Union Officials Representatives of Employer Associations Senior Industrialists Commission Members (State and Federal) Sundry (Journalists, Government Officials). This paper seeks to give an account of their views on various aspects of industrial relations. The interviews conducted were all on a personal and confidential basis so it can be expected that sources will not be identified. Suffice it to say that this account represents, albeit in "potted" form, the opinions of some of the most experienced individuals in the country. It will be seen that in most of the vital areas there is a remarkable lack of consensus. It should be noted that this lack of consensus existed within each of the groups mentioned.

Jan 1, 1980

The concept of "profit" is implicit in the definition of an ore reserve. It is suggested that the flexible concept "economic" is more appropriate. This allows different economic considerations to be taken to account when determining what is ore at the feasibility study stage; during actual mining production; before mine closure; and from the viewpoint of the national economy. Economic factors which are highly variable, and largely beyond a mining enterprise's control, affect the economic exploitation of a mineral resource. Major economic factors include: metal prices; operating costs; the cost of original and replacement capital equipment; the cost of capital; taxation and royalties; inflation; exchange rates and the state of the world economy. The paper suggests why a careful quantification of the average value, trend, and variation from the trend of major economic factors should be made and how this will lead to a better definition of ore reserves. The paper also discusses the necessity of reappraising economic factors during the life of a mine in order to maximise the economic surplus and to minimise the wastage of natural, economic and human resources employed in mining.

Jan 1, 1979

Two examples of risk assessment and risk management in action are discussed. The first is in a management context in relation to Kingsgate Consolidated LtdÆs Chatree operation in Thailand. Kingsgate has conducted an over-riding risk management program to assess and manage risk across its complete business from the Sydney and Bangkok offices through to the Chatree Mine and the companyÆs exploration group. This example addresses how Kingsgate has applied risk management, particularly to the process operation, and the benefits that have been gained. The second is in an operational context in relation to Minara Resources LtdÆs Murrin Murrin operation in Western Australia. The subject is the methodology and outcomes of a risk assessment across the Murrin Murrin operation specifically to identify and assess risks with potential impacts from $1 M to $7 M. This section of the paper then shows how the outcomes of the risk assessment were integrated into MinaraÆs strategic plan to debottleneck the plant and increase nickel production.

Jan 1, 2004

It is my role at this juncture to report to you on behalf of the Council of Mining and Metallurgical Institutions itself. In essence, the Council is an orbital body - a little like Halley's Comet - it returns to earth, in spectacular style, once in every four years. We must acknowledge, however, that the spectacle is provided by the constituent member body organising the particular event and, on this occasion, it is The Australasian Institute of Mining and Metallurgy. On behalf of the Council and its other constituent bodies may I thank the Australasian Institute most sincerely. Our thanks go to Sir James Foots, the President of the 13th Congress, and to all the members of the organising committee and to the five sub- committees. Over 40 people are involved as full members and I am certain there will have been many more involved in very meaningful ways. None of this great- team would ask me to mention them individually, I'm sure, but to fail to acknowledge the role of John Funnell, the Honorary Secretary, would be an unforgivable omission. We must also thank the kindred institutions in Japan, Korea, Thailand, Malaysia, and Indonesia who all helped with the tours themselves or with the initial preparations. Qantas, Jetabout Australia, and Jetabout Singapore have all also made very important contributions and, in our different ways, we each owe our thanks to them. At the two most recent meetings of the Congress - in Hong Kong and Johannesburg - Professor Marston Fleming made this report on behalf of the Council and was supported on both occasions by Robert MacWilliam as vice- chairman. Marston died in 1983 and Robert died in 1984; both men contributed a great deal to CMMI and we will miss their counsel for a long time. As you know, Sir Alistair Frame succeeded Marston Fleming as chairman in 1984 and I succeeded Robert MacWilliam as Vice-chairman.

Jan 1, 1986

By M Robotham

In April 2013, Rio Tinto Kennecott Copper’s (RTKC) Bingham Canyon mine experienced what is arguably the world’s largest ever in-pit slope failure. The failure initiated along a major, continuous, low-strength bedding fault, named the Manefay bed, and comprised approximately 145Mtonnes of rock and waste dump material. Initial East wall slope deformations were detected some months prior to catastrophic slope collapse by RTKC’s slope monitoring systems. However, the failure mechanism was different to that which had historically been experienced in the prior more-than-100 years of open pit mining. Failure occurred as two separate events, the initial one likely consisting of a frictional failure of rock materials along the Manefay bed itself, before a second phase of failure occurred, which included a large mass of old rail dump material. The combination of these events led to a much larger failure run-out than had been anticipated by the RTKC team which led to loss of, and damage to, mining equipment and infrastructure as well as significant interruption to mining activities. Due to the diligent monitoring of the slopes no safety impacts were experienced at the mine, and as such the details and learnings from this failure can readily be shared with the broader mining and geotechnical industries to avoid similar recurrences elsewhere. This is an extended abstract only. CITATION:Robotham, M, 2018. Bingham Canyon Mine – from adversity to excellence, in Proceedings The Fourth Australasian Ground Control in Mining Conference (AusRock), pp 3–4 (The Australasian Institute of Mining and Metallurgy: Melbourne).

Nov 30, 2018

The paper deals with the taking of soundings in connection with coal mining operations under part of the Pacific Ocean adjoining John Darling Colliery.INTRODUCTIONIn the early days of mining in the Newcastle District there did not appear to be any definite law specifying the limits to which mine workings, other than certain borings, could extend under tidal waters.As time went on, a figure of 120 ft. was fixed as the minimum thickness of strata between the roof of the seam and the sea bottom; beyond this mining operations are disallowed. The laws relating to working coal under tidal waters are as follow:-The minimum width of pillars to be left shall be eight (8) yards and the maximum width of bords or other excavations shall be six (6) yards, but the lessee may at his discretion increase the minimum width of the pillars or decrease the maximum width of the bordsor other excavations so as to increase the general safety.The eight (8) yard pillars shall be left unwrought.In on-road of every pair of Winning-off or leading headings, a bore shall be kept going ten (10) feet in advance for the purpose of foretelling the presence of any fissure, wash-out, open joint, fault, dyke, or otherwise, and all winning-off headings shall be driven atleast one hundred (100) yards in advance of the working bords.The most accurate and trustworthy information shall be obtained by the lessee not only' of the depth and character of the ocean bed, river, lake, or estuary deposit, but also of the strata overlying the coal seam.When working under the ocean, strata shall be bored through and proved a minimum thickness of thirty (30) feet at the face of the leading headings or levels immediately such headings or levels are under the ocean, and...

Jan 1, 1947

By W J. Bruckard

In Australia, ilmenite is produced from beach sand deposits. These deposits contain varying quantities of the valuable minerals zircon, rutile and ilmenite, along with a variety of other minerals. The valuable minerals are upgraded using combinations of gravity, magnetic and electrostatic processing techniques to yield high-grade products. One of the penalty elements present in ilmenite concentrates is chromium, present mostly as chrome spinels. This mineral is particularly difficult to separate from ilmenite, as the properties of the two minerals are very similar in relation to the traditional separation processes. While the deposits which have been treated in Australia in the past have had only low levels of chromium present, many of the newer deposits contain much higher levels of contamination and, thus, there is an increasing need to develop robust processes to separate chrome spinel from the ilmenite. Flotation, which is a unit process with the potential to solve this problem, has surprisingly received little attention for this application. The literature suggests the research effort to characterise the general flotation properties of chromite (chrome spinel with high chromium content) has been extensive and a substantial amount of data is available. However, the problem of separating a small amount of chrome spinel from a large amount of ilmenite requires a different approach to that from separating chromite from siliceous gangue, which has been the main commercial focus of chromite flotation in the past. Much of the work done has been fundamental in nature and the results obtained are fairly inconsistent, as is the testwork completed at batch and pilot plant scale. While these inconsistencies have been attributed to the variable composition of the mineral, there is little evidence supporting this premise. Just as chrome spinel and ilmenite have similar physical characteristics, the flotation response of both minerals is also similar. This paper reviews the literature relating to the flotation of chrome spinel and presents a considered approach to the development of a robust flotation method to separate chrome spinel from ilmenite.

Jan 1, 2001

The Australian Mining Industry Council is the peak mining industry representative body in the country. It is wholly funded by its member companies which comprise all of the major Australian mining houses. AMIC represents companies invo

Jan 1, 1994

By Tenorio J. A, Vieira C. B, Sobrinho P. J N

This paper shows a review of bibliography and actual situation of the plastics injection into blast furnace. Some information about results and experimental practice with plastics waste are presented as well as the development of the injection plastics's technique.

Jan 1, 1999

Zinc enters into solution on aeration of sphalerite in deionised water. It has been observed that less zinc dissolves in a copper vessel than when the same operation is carried out in a glass vessel of similar shape and size.

Jan 1, 1980

The purpose of this paper is to review recent approaches by regulators, employers and employees and their associations to the introduction of flexible employment practices and the management of fatigue related risk. More importantly, it will focus on developments in our law either through legislative change and cases which have dictated trends. The paper particularly considers the limitations imposed by occupational health and safety legislation to resist or limit the move to flexible workplace practices on the basis that such practices are unsafe.

Jan 1, 2003

The intention of this paper is to give a review of the present status of lignite mining in the so-called Gulf States in the United States of America, namely Texas, Arkansas, Mis- sissippi and Louisiana. The situation in these states is similar to the situation in Australia in that "Strip Mining - 45 m and Beyond" repre- sents the main technical problem to be over- come in the near future. The solution lies in the application of the bucket wheel excavator.

Jan 1, 1981

In February 1974 a continuous synthetic polymer dosing plant was installed at Hamersley Iron Pty. Limited's Pellet Plant at Dampier. The polymer, supplied in a liquid sus- pension, is used to improve the drying characteristics of green pellets. 'Three years of test work were involved in the development of the use of polymers. Polymer is continuously dosed to the balling spray water system at a rate determined by the flow of spray water to the discs. Problems have been experienced with handling the polymer in 44 gallon drums, the increased viscosity of the spray water, disc overloads, increased bed strength and increased "stickiness" of pellet fines.

Jan 1, 1974

By K Heiskanen

Flotation is affected by several factors, part of which depends on the mineralogical characteristics of the ore and part on process variables. Sulfide Ni-Cu ores occur typically in mafic and ultramafic igneous rocks. Serpentine minerals are also common. As a consequence of metamorphosis, sulfides and secondary minerals may be finely disseminated in an altered ore matrix. The floatability of minerals depends also on process variables. Oxidation of sulfide particles, process iron and dissolved ions in process water affect the behaviour of sulfides. The effects of some essential factors on flotation of Ni-Cu ores are considered.

Jan 1, 2005

Good morning ladies and gentlemen. It gives me great pleasure to talk to you today about a pet subject of mine, on when to mill and when to leach gold ores. According to Gold Fields Mineral Services of London, gold production in the United States in 1989 amounted to about 8.5 million ounces (259t), an increase of 29 per cent over 1988 and 67 per cent over 1987. The U. S. Bureau of Mines reports that from the major producing states of Nevada, California, Montana, and Alaska, some3.2million ounces of the 1989 production were produced from milling gold ores and 2.3 million ounces from heap or dump leaching. Ap- proximately 45 million tons of ore were milled and 140 million tons of ore were heap or dump leached.

Jan 1, 1991

By J Zhiming, X Qian

All high stopes and pillars in Anqing Copper Mine were extracted by use of large-diameter longhole mining method. The height of stopes was 120 m. The forced mining was the leading concept that the safe and efficient operation was carried out in this mine, while the mining production was faced with the major technical problems on the stability of both primary ore pillars produced in the first-step stoping of stopes and the cemented fillbody on two sides of stope in the second-step stopping of pillars. Starting with mining technology, the authors emphatically describe the test results obtained in Anqing Copper Mine and make an approach to the deployment prospects and development trend of large-diameter longhole mining technology in China underground metal mines.

Jan 1, 2000

The Elgas Underground Storage Facility at Port Botany, Sydney, is the first purpose-built cavern of its kind in Australia and provides large capacity, safe and environmentally benign storage of Liquefied Petroleum Gas (LPG). The facility will provide Elgas with the flexibility to source product at competitive prices and ensure long-term security of supply. Construction has provided Orica Australia, formerly ICI Explosives, with a unique opportunity to provide a bulk explosive delivery system specifically designed to meet the exacting demands of the site and of the project.

Jan 1, 1999

By Khosrowshahi

A scientific approach to analysing grade control has been applied at a number of mining operations. By dividing the grade control process into the various stages of data collection and interpretation, errors can be identified using reconciliations of production against predictions. The merits of different mining styles in large and small open pit mines are examined.One factor in successful grade control is estimation of the expected ore loss and dilution. Empirical methods developed in two dimensions have been refined to enable 3D modelling of the effects on mineable grade and tonnage of varying the bench height, sampling orientation, and sampling Resolution.

Jan 1, 1992