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Continuous processes must be shutdown and restarted regularly. Results from the study of operating plants showed potential value for computer simulation of the shutdown and startup of stirred tank leaching reactors. Simulation allows operational variables such as feedrate, and process variables such as the dissolution kinetics to be altered to establish trends in behaviour. Results are presented for the start- up of a cold, empty, single stirred tank reactor, in which three solids are leached at elevated temperature at steady state. Increasing the average temperature in the reactor during startup did not change the fraction of 'valuable' solid dissolved in the first product but it did increase the fraction of slow dissolving (impurity) solid dissolved.

Jan 1, 1984

A broad zone of intra-plate volcanism occurs for some 3000 km along the E. Australian coastal regions, extending from far northern Queensland southwards to Tasmania, westwards to western Victoria, and into southeastern South Australia. The age range, taken over the whole region, extends from Eocene to Holocene. Wellman & McDougall (1974) recognised the occurrence of three distinct types of volcanic occurrences: (a) Lava field provinces, dominantly basaltic and commonly strongly undersaturated, but of variable size. Large lava fields are especially exemplified by the younger provinces in northern Queensland (e.g. Nulla, McBride), and western Victoria. (b) Central volcano provinces, in which a reasonably well defined volcanic edifice is discernable. Such provinces are built of mildly undersaturated to saturated mafic lavas, but are also characterised by felsic volcanism (and often substantial mafic and felsic intrusive phases). Examples are the Springsure-Minerva Hills province, the Tweed and Focal Peak Shields (southeastern Queensland to northeastern N.S.W.), and the Nandewars, Warrumbungles, and Canobolas volcanic centres (N.S.W.). (c) A single leucitite province in N.S.W. Wellman and McDougall (1974) were able to show that the central volcano provinces exhibit a remarkably regular southward age migration pattern, the calculated migration rate being 66 + 5 mm yr , and these authors interpreted this in terms of the northward passage of the Australian plate across a fixed 'hotspot' within the upper mantle. The leucitite province also fits this migration pattern. The lava field provinces apparently exhibit more erratic regional age distribution patterns, but Sutherland (1981) has interpreted the data in terms of a multiple 'hotspot' model. It is noted, however, that the youngest areas of volcanism (Pleistocene 1. Department of Geology and Mineralogy, University of Queensland, St. Lucia, Brisbane, Queensland

Jan 1, 1987

Mt. Whaleback is in the Pilbara region of Western Australia approximately 1200 kilometers north of Perth, the State capital. In this deposit the Mt. Newman Joint Venturers are mining ore reserves totalling 1500 million tonnes of high grade hematite averaging 64.0% Fe. In addition to Mt. Whaleback, 38 ore bodies have so far been identified outside Mt. Whaleback on the Company's remaining 75,000 hectares of lease area. These ore bodies contain major tonnages of iron ore. Extraction at present is planned at a rate of 37 million tonnes per annum at an ore-to-waste ratio of approximately 1 to 1.4. The ore is railed north to Port Hedland on the Indian Ocean where the different products are screened, crushed and blended prior to shipping. The purpose of this paper is to acquaint the reader with the facilities installed in the Mt. Newman operation to form a background to the sampling techniques employed, describe the precisions which were achieved in experiments conducted February through June, 1976 and also to assess the degree of blending which takes place during the various processes and to put a quantitative measure to the degree of blending. There have been many excellent papers written on the more theoretical aspects

Jan 1, 1976

This monograph presents a unified theory of adsorption and desorption of aurocyanide on activated carbon. This theory has proved useful for CIP/CIL carbon adsorption and Zadra and AARL elution process and equipment design; in accounting for the effects of various water qualities and process temperatures; and in the development of reagents to improve these processes. The theory presented is based on rigorous fundamentals : Classical Eyring theory links initial first order kinetics with Langmuir isotherm equilibria, and this isotherm is demonstrated for the first time to be a consequence of the activated complex postulate of Eyring theory. Simple extension to Freundlich conditions at high solution tenors is possible, but not presented. Supporting entropy data determined by the author includes practically all the pioneering CIP plants built in South Africa and Australia in the early 1980s.

Jan 1, 1991

By Jeffery RI, Pollard CA, Fear NJ

The paper describes the detailed hydrogeological studies carried out prior to the sinking of twin shafts at British Coal's new mine at Asfordby, Leicestershire, UK. The test methods for assessing potential groundwater inflows to the shafts are discussed and details are given of the ground freezing scheme employed through the major aquifer zone in the Sherwood Sandstone at a depth of 375 metres. During shaft sinking pressure recovery tests were carried out to further assess potential inflows and the results are compared with those from the surface tests prior to sinking.

Jan 1, 1988

By Glatthar J. W, Lauder D. W, Manlapig E. V, Mackinnon I. R

The Ok Tedi copper orebody consists of porphyry and skarn orebodies. The skarn orebodies, identified by different mineralogies, are the source of high intermittent fluorine levels in the mill concentrates. This paper discusses the results of t

Jan 1, 1998

By Virtanen M

Grinding has been one of the areas of major development at Outokumpu's concentrators. During its early years the company used entirely rod and hall mills, but due to the high costs of metallic grinding it began the testing of autogenous grinding as early as the 1950s. In the late-1970s, the company's own modification for two stage autogenous grinding was ready for industrial use. Surprisingly late, in the 80s - 90s, an interest rose to check also the effects of grinding methods on flotation results. This paper firstly gives a short history of the development work of Outokumpu type autogenous grinding, called 'Outogenius'. The effects of some grinding methods on the process results of two nickel ores are then reviewed. The tests to date show notable effects of grinding methods on flotation.

Jan 1, 1996

By Skinner J, Brackenbury K

The AuPlus" Systems have been applied in the gold mining industry to achieve improved gold recoveries, faster leach kinetics and reduced cyanide consumptions. Calcium or hydrogen peroxide, collectively known as peroxygens, can be used. The choice depending on plant design and the nature of the ore. Laboratory test work and plant trials are included in this paper to illustrate the benefits of peroxygen usage in extractive gold metal- lurgy.

Jan 1, 1991

By K S. E, S C. Parker, T K. Kundu

Understanding the fundamental principles governing the reactions at surfaces has always been the goal of theoretical surface science. The atomistic simulation techniques have been used to calculate the surface structures and the stability of quartz and wollastonite, and their adsorption behaviour in the presence of molecular and dissociative water, and the two widely used collector head group molecules of methanoic acid and methylamine. The dissolution behaviour of wollastonite has also been modelled. The calculated surface energy, hydration energy and reaction energy values have been examined and discussed in the light of flotation literature. These studies have given an insight into the interactions at atomic level, which indicate that modelling techniques should be capable of predicting the adsorption behaviour and to design the selective collector molecules, which is of central importance to the mineral processing technique of flotation.

Jan 1, 2005

By Poole GR

An unusually high flow of water from an oxtr.iction panel in Wongawilli Colliery pr,;npted the investigation of the possible sources of the water. It is more probable that water is derived f r,m sources adjacent to or within the Woo ' iwi 1 I i Coal rat her than by direct t r.onnuni n i"n from any surface source.

Jan 1, 1986

By Grieve BL

For a blast to be successful both heave and fragmentation must be satisfactory. Amongst the major factors influencing blasting are rock properties. This paper considers the effect of rock density on fragmentation and heave and how better results can be achieved in dense ore. Patterns which increase the heave and give better fragmentation are examined and the application of theory to the blasting of the Dales Gorge Haematite, density 4.2 - 4.5 t.m.,3 is then discussed. The drilling of staggered patterns instead of square patterns and a shallower 'V' initiation system has given better heave and fragmentation. This practice has re- duced backbreak and improved toe conditions; these factors have resulted in increased load ing rates. There has been an increase in the lump/fine ratio which is consistent with the theory although other factors such as ground conditions could have contributed.

Jan 1, 1978

By Barrett D

The paper discusses the justification for the Open Pit Mining Operation at Central Norseman Gold Corporation Limited's North Royal facility.Open pit mining history is outlined together with production statistics and associated costs. Underground mining practice is discussed together with an outline of the problems with mining in oxidised ground.

Jan 1, 1984

The paper poses certain questions relating to mine design aspects of deep shaft pillars. It then explores these questions in relation to Western Deep Levels (South) where a sub-shaft system is to be sunk to 4 000 metres below surface to exploit two narrow tabular reefs in the down dip extension of the mine workings. After brief discussion of some broad considerations, the findings of a major rock mechanics investigation are reviewed. Some overall conclusions as well as the outcomes of separate studies of the anticipated behaviour of shaft pillars on each of the two reef horizons are outlined. The effect of this behaviour on the barrels of the shafts in the system and on the associated shaft excavations and in-pillar development is Cnnctdarcrl

Jan 1, 1986

By Mutton B. K

Hilton Mine is being developed as an integrated component of the Mount Isa operation, to achieve continuity of silver/lead/zinc production well into the next century. The mine has a chequered history from its discovery in 1947 through several periods of intense development activity, each of which has been curtailed due to the further development of the Isa Mine operation. This era has now passed; to sustain increased production rates at Mount Isa, there is a requirement for Hilton ore in 1989. The decision was made in 1983 to accelerate the programme of Hilton development by installing skip hoisting facilities in the main service shaft (P49), to facilitate the development of the mine to pre-production status. The Hilton development plan provides for the mining of selected orebodies, a broadening of the underground exploration drilling programme, and the establishment of significant mine infrastructure. Several technical challenges have been identified as important. The Hilton orebodies, although occurring in the same rock type as Isa Mine, are more faulted, jointed and intersected by intrusive dykes. The ore is more variable in terms of ore continuity, boundaries, grade and metal distribution and the mineralogy more complex. As a consequence the development of this project consists of a co-ordinated programme of mine exploration and development, rock mechanics investigations and metallurgical research and development work. Production will commence in 1986 at a rate of 1000 t/day using mechanized cut and fill techniques. It is planned to introduce sublevel open stoping and by 1996/97 the production rate will be 2.5 million t/yr.

Jan 1, 1986

This paper reviews factors involved in the feasibility stage of underground mine project development. Emphasis is placed on the need to first select the best method of extraction and make the most accurate assessment of the expected output even with the uncertainties which may exist in structural interpretation, ground stress, geotechnical factors, and industrial conditions. The subsequent engineering planning should be undertaken from the point of view of the face requirements and is subject to constraints imposed by the method of work and nature of the deposit and, in the case of access, to surface constraints and services.

Jan 1, 1983

By Jones BH

Discovery of the Vera-Nancy deposit in late-1995 followed 12 years of active exploration in and around the Pajingo Epithermal System, an andesite hosted veinfield covering an area of 150 square kilometres at the northern end of the Devono-Carboniferous Drummond Basin in North Queensland. Early exploration targeted open-pittable resources in the numerous auriferous veins and it was not until 1994 that exploration focus shifted to drilling to depths below about 100 metres from surface, which resulted in the Vera-Nancy discovery. That deeper drilling process is still at a very early stage of coverage of the epithermal system as a whole and substantial potential exists for additional discoveries.Drill-out of Vera-Nancy has to-date established a gold resource in excess of 1.4 million ounces. Mine development is proceeding via a twin decline system with first stoped production scheduled for August 1997.

Jan 1, 1997

The Mount Morgan massive sulphide body occurs in a volcanic sequence of Lower or Middle. Devonian age, which is subdivided in the mine into "Upper mine porphyries", "Banded mine sequence", and "Lower mine porphyries". This sequence is intruded by latite, Mount Morgan Tonalite (360 million years), and late Permian dykes. Distribution of macroscopic ore textures and minerals in the orebody are discussed and evidence is presented indicating the pre-Tonalite, Devonian age of the orebody.

Jan 1, 1974

By A Boeing

Rock-breaker automation and remote operation improves the safety and efficiency of mining operations. This paper presents an overview of the Rocklogic rock-breaker automation system architecture that provides collision avoidance, automated parking and remote operation functionality. The system consists of a distributed computer control system that interfaces with sensors attached to the rock-breaker, the rock-breaker hydraulics and the site infrastructure. We present results of an automated Transmin rock-breaker installed in a production environment at an underground Australian mine site. The system has been in production use for over 900 days, during which there have been no reported collisions and 100 per cent adoption of the remote operation technology. As a result, Rocklogic has significantly improved the safety of rock-breaking operations and reduced the rock-breaking cycle time, thereby improving the site’s overall throughput.CITATION:Boeing, A and Douglas, E, 2014. A remotely operated robotic rock-breaker with collision avoidance for the mining industry, in Proceedings 12th AusIMM Underground Operators’ Conference 2014 , pp 131–136 (The Australasian Institute of Mining and Metallurgy: Melbourne).

Mar 24, 2014

By Brien R. J, O&apos

Faster and more efficient methods of producing and refining iron and steel are imposing severe conditions on the refractory materials used to contain these metals in the molten state. In order to provide refractory linings which will give the desired service life and maintain unit availability at an economical level, it is necessary to appreciate the aggressive environment in which the refractories operate and determine the reaction mechanisms by which the refractories are destroyed. Only by such studies can the most suitable refractory or refractory combination for a particular unit be selected. Examples of refractories selection and reaction mechanisms are discussed for blast furnaces, BOS vessels, AOD vessels, steel ladles, vacuum degassing units and continuous casting.

Jan 1, 1976

The Que River Mine is a small under-ground base and precious metals mine located in north-western Tasmania. Current production rate is 220,000 tonne/yr from reserves grading 0.37% copper, 7.1% lead, 12.2% zinc, 195 g/tonne silver and 3.4 g/tonne gold.Ore is mined using longhole open stoping techniques. Cemented fill is placed in primary stopes to permit safe and efficient recovery of pillars. The operation is trackless with both shaft and decline access from surface.Ore produced is trucked 40 km by road to be sold to the Electrolytic Zinc Company of Australia Ltd., for treatment at their Rosebery concentrator.

Jan 1, 1985