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The cost of power is an important matter to mining companies generally and this thought that the members of the Australasian Institute of Engineers, as well as the engineering and mining professions generally would be interested in any proposal for the reduction of that cost has led to the presentation of this paper.The writer trusts that the description will be found clear and increase the interest in this interesting subject. In the up of the electrical arrangements touched on in this paper, the author has had the able assistance of his friend Mr. Mars, to whom he offers his hearty thanks. The selection of the best class of power plant for a mine is a very difficult and large problem and it is quite out of place to dogmatise that anyone of the many systems that offer is better than another, eg that the all electrical is better than the partly direct steam-driven and partly electrical, or that a gas plant is better than a steam plant. Such a selection is one that calls for very careful and close consideration, in each particular case, of a large number of before it is possible to arrive at a proper decision.

Jan 1, 1912

By Peter White

A bridge reconstruction project involved driving pipe piles for the new foundations. Disturbances within soil layers at depth caused sinkholes to open up within the construction site. After a near fatal accident, the pile driving installations were suspended. The solution involved ground im­provement through cement grouting with sleeve pipes and special grout additives to minimize migration of cement grout.

Jan 1, 1997

Flotation Research on Cassiterite of Tailings

Sep 13, 2010

As the chief field of the gold dredging industry in Otago is the district traversed by the Molyneux River (called above Cromwell the Clutha) and its tributaries, a brief reference to the geology of that region and the origin of its alluvial gold will not be out of place. The prevailing rocks are metamorphic schists, chiefly mica and quartz schists, pr.obably of Silurian age. Though these rocks do not contain many payable quartz reefs, gold appears to be distributed in small quantities all through them,chiefly associated with the quartz lamime and lenses. The river drift, however, contains numerous pebbles of quartzite, quartzoze conglomerate, and fme-grained slate. Seeing that these rocks are hardly known to occur in situ within the watershedof the Molyneux River, though Devonian and carboniferous rocks of similar character occur to the north-east and south-west, it seems probable that the schists were at one time overlaid by carboniferous and Devonian rocks, and that these have been removed by denuding agencies. Be this as it may, it is certain that the schists themselves have been greatly eroded by the action both of water and of ice, and that the resulting drifts have themselves, in many cases, been sorted and re-assorted by the same agents.Consequently the drifts are very varied in character and often developed on a grand scale. In geological age they vary from Early Tertiary (though some may be older) to Recent.

Jan 1, 1903

Mineral Processing Engineering Education in China - Bringing up the Engineering Diathesis and Design Competence of the College Students

Sep 13, 2010

Characterisation of Manganese Ores

Sep 13, 2010

By D M. Menne

This paper is intended to give a general review of current gold extraction technology for free-milling or non-refractory auriferous ores. Fundamental process concepts and some of the differences between the current technologies is referred to. Typical flowsheets and layouts are provided and it is demonstrated that technology for extracting free-milling gold is relatively simple. For environmentally sensitive areas such as encountered in New Zealand relevant cyanide decay and destruction technology is also discussed. Brief mention is made of some likely future innovations. Finally reference is made of New Zealand's previous significant contribution to gold extraction technology. These contributions were pioneering ranging from the cyanide leaching of gold to adsorption by carbon and precipitation by zinc. New Zealand has not allowed its potential gold projects to develop at a rate commensurate with the rest of the world thereby stifling its renowned innovative approach in this technology. It is time for New Zealand mining to recognise its unique opportunities in developing gold extraction technology and again take a rightful place in leading the way.

Jan 1, 1986

By Murat Erdemoğlu, Turan Uysal, Thierno Saidou Barry, Mustafa Birinci

The rapid development of the global alumina and aluminum industry is straight coupled with the demands and the needs of these materials. Nowadays, the only well-known accessible resources to produce alumina and aluminum are bauxite ores. But bauxite ores are limited, and the remaining exploitable reserves do not have high contents in alumina. In countries where there is little or no bauxite reserves or where the recovery of existing bauxite ores to produce alumina with the Bayer process are not economic, alternative resources for alumina have been explored. The most attractive resources for replacing bauxites are aluminosilicate clay minerals and coal fly ash. The important processes developed for the recovery of alumina from these sources are acid leaching and alkaline leaching processes. The acid leaching is known as the most efficient in which thermal and mechanical activation are included for improving the performance of the process. The objective of this review is to give a comprehensive insight on the production of the alumina from thermally or mechanically activated clays and coal fly ash by hydrochloric, sulfuric, and nitric acid leaching processes.

By E Oktay, I Yusufoglu, C Kahruman

Powder and spherical pellets of MoO2 were oxidised under controlled conditions in the temperature range 674-791 K at oxygen partial pressures of 8.1-30.4 kPa. Weight increase during the reaction was determined by thermogravimetric analysis. It was concluded that the reaction is 0.6th order with respect to oxygen concentation and that the activation energy is 148 kJ/mole. In experiments conducted with powder, fast transfer of reaction heat to the gas phase created isothermal conditions, but the temperature of pellets rose by a maximum of 54 K at 674 K and 105 K at 791 K. The rise in temperature caused structural changes such as sintering and crack formation, which had a considerable effect on the reaction rate. The findings should be taken into account in the design of equipment and choice of operating conditions for roasting MoS2

Jun 21, 1905

By Nural Kuyucak

Several thousand years ago, metallurgists discovered that by combining two relatively soft metals, copper and tin, they could make a new material, bronze, that was stronger than either metal separately. Bronze and other alloys show how different materials can be integrated to create something new and better. Today?s mining industry can likewise find benefit in an integrated approach to managing the external impacts it has through its waste materials and its use of water. Just as using bronze gave ancient nations an economic and military advantage, mining companies can gain competitive advantage through finding better ways to manage water and waste. Trends pushing this include: ? Environmental ? Regulations on water-taking and the quality of discharged water are becoming more stringent. Net zero discharge requirements are often imposed by regulators. Mining companies also come under pressure to manage environmental impacts of mine waste, including minimizing the area occupied by waste and seepage amount resulting from infiltration of water from a smaller surface area. ? Social ? Particularly in arid parts of the world, there are multiple possible uses for each gallon of water. Local residents do not want to see a reduction in supplies of water for agricultural, domestic, manufacturing and other purposes. They get suspicious about any potential impact of water being mixed with their water reservoirs if it comes from a mining site, even if it would be treated. Such suspicions may cause conflicts among the stake-holders and delays in project approval processes.

Jan 1, 2009

By H. K. Taylor, B. Denby, L. D. Smith

Contributions by H.K. Taylor and G.A. Davis discuss the three papers published in Transactions IMM A, vols. 103 and 104, with responses by Smith and Dowd

Dec 1, 1995

By M. Foguenne, A. van Lierde, P. Henry

Leaching experiments were carried out on a spent catalyst sample with a honeycomb structure, containing 47.5% Ti, 5.8% Mo, 2.7% Si, 2 035 ppm As, 52 ppm Pb and 8.8 ppm Hg. More than 93% of the Mo and As was removed by direct alkaline leaching after grinding to 80% -36 micrometres. The residue contained 0.3% Mo and 60 ppm As. To obtain a TiO2 matrix with 30 ppm As, acid leaching at controlled pH with 90 kg/t Al scrap was followed by oxidising alkaline leaching. Treatment of the direct alkaline leach solution or of the mixed solutions from the two-stage process involved two successive operations: purification by neutralisation with Al(OH)3 addition to raise the Al concentration to 4 g/l, and ion exchange on Amberlite IRA 94 S resin. Whatever the type of solution treated, elution with 200 g/l NH4OH solution gave an eluate of very high purity containing 164 g/l Mo, less than 70 mg/l V and less than 2 mg/l As

Jun 19, 1905

By R. M. Cooper, H. K. Herbert, D. N. Phillips

A study was carried out to determine the effects of adding CaCO3, Fe, Al and CaSi2 to the ladle, rather than to the raw materials, in order to increase the concentration of Ca, Fe and Al in the final product to meet customer specifications at Simcoa's Kemerton plant in Western Australia. LA-ICP-MS, SEM-EDXRA and ICP-AES analysis of samples and controls showed that the technique is suitable for controlling minor element concentrations. Iron was successfully added, while calcium silicide with aluminium proved better than limestone with aluminium for controlling Ca and Al concentrations in the silicon

Jun 19, 1905

By M. Schafer

The 6-m- (20-ft-) diameter cast-in-place tunnel lining for Phase 3 of the Mill Creek Tunnel (MCT3) has been completed. This article summarizes aspects of liner design and ad-dresses the construction approach in placing the liner in areas of tunnel that experienced crown overbreak. Tunnel lining production rates, installation procedures and form buoyancies experienced during concrete placement will also be presented. The Mill Creek Phase 3 tunnel (MCT-3) is expected to be completed this year. It is one of the largest tunneling projects undertaken by the Northeast Ohio Regional Sewer District (NEORSD) to date. The tunnel horizon is situated within the Devonian Chagrin Shale rock formation at an average depth of 85 m (280 ft). The tunnel was excavated using a two-pass method. A full face, fully shielded, Robbins 7.2-m- (23.8-ft-) diameter tunnel boring machine (TBM) was used to excavate approximately 4,500 m (15,000 ft) of tunnel and facilitate installation of initial supports (first pass). The final lining (second pass) consists of 305-mm- (12-in.-) thick cast-in-place reinforced concrete and integral low flow channel. Seven shafts were constructed on the project. The excavation of the tunnel commenced at Shaft 14 and proceeded down grade to Shaft 9, the terminus shaft. Because of the presence of overbreak in the tunnel crown, measures were required to support the form and counteract the effects of buoyancy during concrete placement.

Jan 1, 2008

A new lead refinery with a capacity of 230,000 tons per year commenced operation at Port Pirie in October, 1959. This plant superseded the refinery which had operated from 1933 with the advent of the continuous lead refining process. The incorporation of new equipment following local metallurgical developments, together with the overseas demand for lead of extremely low antimony content createddifficulties in operating the original plant. The new refinery project was undertaken to cover this disability and to gain the full advantage of the new processes.Desilverising and softening are carried out in units identical in size to those used previously. Metallic zinc is recovered from the entire output of desilverised bullion by vacuum distillation. Final refining is carried out by batch treatment with caustic soda yielding lead of purity previously unattainable at Port Pirie.These two processes replace continuous dezincing by oxidation, a high temperature process which caused large quantities of lead and antimony to be recirculated. The final stage is a batch process; therefore the product composition can be checked before casting. Individual batches can be adjusted to produce special alloys to consumer's specification.Improved casting equipment allows the quantity production of pigs of good physical characteristics either as 56 lb bars or 2000 lb pigs.This, together with the high purity of the lead, assures the Broken Hill Associated Smelters Pty. Ltd. (RH.A.S.) position in world markets.Automatic control systems are extensively employed, particularly on the vacuum dezincing unit.The anticipated financial benefits have been achieved mainly by a reduction in the tonnage of recirculated materials, a smaller labour force, and reduced maintenance requirements.INTRODUCTIONIn December 1956 a decision was made to build at Port Pirie a lead refinery on a completely new site, and in October 1959 the new refinery was brought into operation. This plant superseded the lead section of the old refinery which...

Jan 1, 1963

By Arturo Ressi di Cervia

From the times when men in lacustrine environments drove wooden piles into the mud to elevate their dwellings, until the beginning of the twentieth century builders reacted to the conditions found in the location of their proposed structures by attempting to distribute their loads in ways that could be supported by the foundation's soils; or, if those were unsuitable, by moving the structure, whenever possible. While many major structures were built on stable ground (the pyramids were founded on rock), others were built on [ ]

Jan 1, 2000

"WELCOME/BIENVENUE TO THE COM 2014 IN BEAUTIFUL VANCOUVER!On behalf of the organizing committee, I would like to extend my thanks to you for participating in this year’s Conference of Metallurgists. Recent times have been extremely difficult for the resource sector, but it is crucial for our industry to maintain personal connections through good and bad times. These interactions include technical exchanges, and this is at the heart of MetSoc’s service to its members. The theme of this 53rd Conference of Metallurgists is Prosperity Through Process Advancements. There are thirteen symposia at this year’s conference mainly focused on processing from extractive fields, to materials and the environment. Supporting these topics are the plenary, poster session, and trade show plus opportunities for socializing at functions like the opening reception and the awards banquet.Many people have contributed to this conference, from the authors and presenters to the organizers and the generous sponsors. They are all gratefully acknowledged for their quality work over the last two years. A particular thank you to our student volunteers whom we hope will take advantage of their time at COM to network and to learn about this exciting industry.Again, thank you for being a part of this exciting conference of metallurgists. I hope it will be a memorable experience and that you are able to take advantage of all the conference and Vancouver have to offer."

Jan 1, 2014

By Derek. C. Arnold

In order to meet increasing demands for water supply in the next millennium, the Government of the Hong Kong Special Administrative Region have identified the need for a major new water treatment and transfer scheme. The project now under construction will comprise a 1.2 km long raw water aqueduct, a major new 0.25million cubic metres per day water treatment works (with space for upgrading to 1.2Mm³/d), a 12.1 km long treated water aqueduct and a primary service reservoir. In order to meet increasing demands for water supply in the next millennium, the Government of the Hong Kong Special Administrative Region have identified the need for a major new water treatment and transfer scheme. The project now under construction will comprise a 1.2 km long raw water aqueduct, a major new 0.25million cubic metres per day water treatment works (with space for upgrading to 1.2Mm³/d), a 12.1 km long treated water aqueduct and a primary service reservoir.

Jan 1, 1999

By Peter J. Nicholson

A new method of constructing retaining walls, in-situ, prior to excavation has been developed. This "Vertical Earth Reinforcement Technique" VERT, has been demonstrated at a full scale test wall at the National Geotechnical Experimentation Site at Texas A&M University. This 10 meter high wall, was constructed of elements of soil mixing in an array that forced composite behavior between the soil mixed elements and the in-situ soils. Inclinometers and extensometers were used to verify the performance of the wall. The construction and results of the testing are presented.

Jan 1, 1998

This paper describes new research and development currently being undertaken by the CSIRO Mining Technology Group to advance the automation capability of continuous mining equipment in underground coal mining operations. The effort aims at increasing the overall rate of roadway development as well as providing a safer working environment for underground mine personnel. The activity is funded by the Australian Coal Association Research Program (ACARP) and forms part of a larger underground development initiative, known as the CM2010 project. The CM2010 is managed via a consortium of leading mining industry representatives through the Roadway Development Task Group (RDTG). The Task Group has identified three research areas requiring new development in order to realise the CM2010 project objectives: self-guiding (autonomous) continuous miner capability, an enhanced drilling and bolting process and improved mesh deployment. CSIRO's primary role in the CM2010 project is in the development of the autonomous continuous miner guidance capability.This paper reports on outcomes achieved at the half-way mark of a three year research and development project. It details the technical developments undertaken towards demonstration of a 'self-steering' capability to enable a continuous miner to automatically maintain a given mining heading and mining horizon under production conditions. A primary technical requirement of this automated functionality is the means to accurately determine both the location and orientation of the continuous miner in real-time. Testing and validation of the guidance system solution has been implemented using a combination of an instrumentation-grade inertial navigation unit and radar technology. Comprehensive performance evaluations have been conducted using a scale skid-steer mobility platform known as the Phoenix. Results achieved to the present stage of the project are highly promising and suggest that an automated self-steering functionality is achievable under production conditions. This new outcome represents an important move towards implementing a step change improvement for future underground roadway development.

Dec 6, 2010