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By V. K. Paruchuri, J. D. Miller, J. Nalaskowski

The phenomenon of surfactant adsorption at mineral surfaces is of significant importance in many particulate processes ranging from mineral flotation and enhanced oil recovery to pharmaceutics, paint technology and the casting of high quality ceramics. Stability of the dispersions is related not only to the amount of adsorbed surfactant but also to the structure of the adsorbed surfactant molecules at the interface. This structure greatly depends on the type of surfactant and the hydrophobicity or hydrophilicity of the surface. On hydrophobic surfaces surfactants adsorb regardless of surface charge by van der Waals/hydrophobic inter-actions with hydrocarbon chains accommodated at the surface. On the other hand, on hydrophilic surfaces the surfactants adsorb through electrostatic interactions with their polar moiety fixed at the surface. In the latter case, the electric charge of the surface and surfactant plays a crucial role in the surfactant adsorption process. The recently developed soft-contact Atomic Force Microscopy technique has revealed images of adsorbed surfactant structures at various interfaces. The adsorbed structures of a cationic surfactant (CTAB) and an anionic surfactant (SDS) are presented in this work for different concentrations at hydrophobic graphite and hydrophilic mica surfaces. Different types of micellar arrangements have been observed at these surfaces for surfactant concentrations around the critical micelle concentration. The structures are more ordered and well defined at the graphite surface than at the mica surface. These results have been correlated with the hydrophobicity of the surfaces as revealed by contact angle measurements.

Jan 1, 2001

The pyrite-sphalerite-galena and barite orebodies at the Rosebery mine are concordant with the shale host rock and have been deformed into one system of folds with an associated axial plane cleavage. The folds are tight and overturned with east-dipping axial planes. Folds in the sulphide ore are commonly disharmonic, particularly between adjacent bands of different composition.Concentric style folds occur in the competent bands, e.g. pyrite-rich bands. Similar style folds are predominant in the less competent sphalerite-galena-rich bands and also in the shale of the host rock. The trends and plunges of the fold hinge-lines are variable but axial planes are of reasonably constant orientation throughout the mine area. The folds in the orebodies are of limited axial extent, approximating to conical folds, and are arranged in en echelon patterns. The fold system was possibly formed in one period of folding by heterogeneous strain that may have been caused by the presence of a mass of tectonically mobile sulphide ore. Lineations parallel to the ore/host rock contacts appear to reflect movement between the ore and the host rock during folding.

Jan 1, 1972

The Study of Jamesonite Flotation Behaviour

Sep 13, 2010

By C J. Pitzer

The prevention of fatal risks is a key objective for the global resources industry, especially considering poor performance with regard to fatality rate reduction and the continued occurrence of mine disasters globally. However, the industry has a credible history, over several decades, of the development and deployment management systems to control potential Serious Injury, Fatal and Catastrophic (P-SIFC) risks. While these systems have had a significant impact on the thinking and approaches to the prevention of fatal risks, fatal accident rates have not shown the desired reduction. Recent fatal and serious injury events in Australia have led to the establishment of several enquiries to further identify improvements that could be considered. Globally, fatal accident rates remain stubbornly high or plateaued in many jurisdictions, and several catastrophic events have occurred, such as tailing dams disasters in Brazil and South Africa, and the recent coalmine disaster in Turkey. Apart from the apparent lack of progress, it is evident that the deployment of critical risk systems has introduced more bureaucracy, slower response systems and additional burdens on already overloaded middle and supervisory levels of management. Organisations are rarely able to effectively tap into the risk source of risk knowledge of the frontline worker and supervisor, for various reasons discussed in this paper. To establish a valid and valuable channel of critical risk information flow from the frontline employee, Debmarine Namibia instigated the development and deployment of a system called SafeSENTRY, where the focus is on the ‘dynamic identification of dynamic risks’. This paper outlines the system, the principles of the design, the range of risk metrics that can be derived from the observations of the frontline operators, and demonstrates how a range of posited shortcomings in critical risk management is addressed how features of the High Reliability Organization (HRO) have been developed.

Mar 29, 2023

By D. Lawrence, H. Lawrence, G. Saevil

Plant operators in the mineral processing industry have been implementing expert systems for several years now, with the intent to increase production and reduce costs. Most systems have been installed on grinding circuits of some type and have proven that the technology is viable in that application. However, few applications on other processes have been attempted for various reasons, such as lack of reference sites, complexity of the process, lack of suitable measurements and lack of confidence in the technology. The successful application of an expert system on an Alumina Calcining kiln is the first such application in the West Indies Alumina Company (Windalco), and demonstrates how this technology can be successfully applied to other processes. The key objective of an expert system is to optimize the process. To achieve this the process must first be stabilized, followed by optimization of the operating parameters. The steps taken by this expert system to optimize the process are: • Check for abnormal conditions and deal with them using a prioritized set of special actions. • Use a selection of rule blocks to stabilize the process. • Once the process is stable, achieve additional benefits through further optimization of the process. The potential benefits that a user can expect to achieve through installing an expert system can be assessed on the basis that performance will improve from that of an "average operator" to that of the "best operator" performing at his optimum for 24 hours a day, every day. The quantifiable process benefits include: • Increased production • More consistent product quality • Reduced operating costs • Reduced standard deviation of key variables • Consistent plant operation The success of this project was measured in several ways: project implementation, realised economic benefits, and realised non-economic benefits. With a commitment to maintain the system over the long term, the longevity of the system is assured and will become an important part of the Alumina Calcining control strategy at Windalco. This paper discusses the various phases of implementing the ABB Expert Optimizer expert system, what the benefits were and the procedure that is in place to maintain the system to ensure continued long term success.

Jan 1, 2002

By D. L. Thompson

Foreword The complete history and early development of the Sullivan mine was fully covered in a paper entitled 'The Development of the Sullivan Mine and Processes for the Treatment of its Ores', prepared by the staff of the Consolidated Mining and Smelting Company of Canada, and presented at the Annual Meeting of the British Columbia Division of the Institute at Trail in October, 1924. At a subsequent meeting at Blairmore, Mr. E. G. Montgomery read a paper on the mine, and in 1926 Mr. M. M. O'Brien brought the subject up to date at the joint meeting of the American and Canadian Institutes at Cranbrook. The present paper is necessarily based largely on these earlier accounts. Discovery and Early Development The outcrop was discovered in 1892 and the property was bonded and later sold to the Sullivan Group Mining Company, of Spokane. From 1896 to 1899, surface stripping and test pits (at A) around the outcrop exposed a vien of sulphides with varying amounts of lead and zinc. In some places, a 35 per cent lead ore carrying 15 ounces of silver was found. These lenses were of commercial value. With the completion of the Kimberley branch of the Canadian Pacific railway, in 1900, some systematic development was started. A shaft l00 feet in depth was sunk (at B). Shaft-house, boiler-room, and compressor-plant were erected, and a steam diamond-drill was put into operation.

Jan 1, 1929

It is shown that factors associated with conditions whIch are thermodynamically favourable for the formation of CuS04 in roasting lead to high copper recoveries on leaching. One of these factors is the ratio of the air to solids used for roasting. This can be varied widely without loss of temperature control in the sulphating roasting of many Australian copper concentrates.Thus, the prediction of the air to solids ratio corresponding to a maximum p(SO3) value, for a given concentrate and temperature, is of importance in fluidized bed roasting, since this could be associated with the formation of a maximum quantity of CuS04. Calculations are presented which predict this air to solids ratio, not only for a given concentrate composition, temperature, and pressure, but also for air which is enriched with sulphur dioxide or oxygen.

Jan 1, 1968

The ore, as sent to the sulphide mill, is a mixture, in varying proportions, of oxidized ore from above the 450-ft. level and sulphide ore from above and below (to date mainly from above) that level. The oxidized ore consists essentially of quartz, with varying amounts of kaolin and clayey material which passes into the slime and, in excess, creates a serious problem in settling. Pyrite may be present in small amounts. The gold is free and extremely fine.The ore, classed as sulphide, consists of pyritic material in a quartz gangue. The sulphides have been exposed to weathering, leaching by descending solutions and attack by ascending gases and actual burning. The alteration products occur in widely varying proportions and this variation adds to the difficulties in settling and control of grinding and flotation.Copper Minerals.-Chalcopyrite is the principal copperbearing mineral with smaller and varying amounts of covellite, which is sometimes associated with chalcocite, both these minerals being apparently of secondary origin.Examination of tailing by Dr. Stillwell has revealed all stages between clean chalcopyrite, chalcopyrite tinged with covellite, covellite with residual cores of chalcopyrite and clean covellite.The chalcopyrite is free floating, very few particles of clean chalcopyrite being observed in the tailing from granular flotation. The chief tailing loss is probably as chalcopyrite occurring as small inclusions in pyrite...

Jan 1, 1939

By L Reynolds

Oceana Gold (New Zealand) Limited (OceanaGold) has commenced mining operations at the Globe-Progress mine in the Reefton Goldfield, an area that historically produced 2.1 million ounces of gold from underground quartz lode deposits. During the construction phase of the operation, advanced exploration programmes targeting near-mine prospects commenced. The focus of this ongoing exploration is the discovery of near surface, refractory gold deposits that are amenable to open-pit mining methods and treatment through the Globe-Progress process plant.   One such discovery is the Supreme deposit, located along strike approximately 3 kilometres to the south of the Globe-Progress mine. The Supreme area was tested extensively with diamond drilling in 2006, defining a deposit with similar mineralisation styles and grade to the Globe-Progress deposit. The mineralisation comprises a central core of gold-bearing quartz veins, locally containing visible gold, surrounded by a more extensive halo of refractory, disseminated gold associated with an arsenopyrite-pyrite sulphide mineral assemblage. Three subparallel mineralised structures host the mineralisation. These structures are highly oblique to the country rock orientations, extending approximately 250 metres along a northeast-southwest strike and at least 220 metres down-dip, with an average thickness of 12 metres and moderate dip to the southeast. Records of historical workings indicate that mineralisation extends further down-dip and remains open at depth. 5175 ounces of gold were mined historically at the Supreme deposit. OceanaGold have defined an Inferred Resource for the Supreme deposit of 0.84 million tonnes at 1.46 grams per tonne for a total of 40 000 ounces (at a 0.8 grams per tonne cut-off). Higher-grade zones of mineralisation exist within the deposit and further drilling is planned to test the extent, continuity and geological controls of the mineralised structures.

Jan 1, 2007

(This paper reviews the reasons for and the principles followed in designing and constructing complete new surface works at the mine of the Zinc Corporation Limited, Broken Hill, New South Wales, and describes the layout, plant, buildings and services.)The Zinc Corporation mine produces high grade lead, silver and zinc sulphide ore. Lead and zinc concentrates are sent by rail to Port Pirie, where the lead is smelted and the zinc concentrate is shipped to Tasmania, England and other overseas countries.Some time ago consideration was given to the advisability of sinking an additional shaft. For some years the old main shaft had been working at full capacity and developments underground had indicated that the mine would eventually be capable of an output greater than that which could be handled through the shaft. It was therefore decided to sink a new main shaft and the site chosen was in footwall country 900 feet south of the old main shaft. The reason for the move south was so that the new shaft would be opposite the centre of gravity of the ore-bodies at depth. The size of the new shaft is 27 ft. ,6 in. x 15 ft., and the work was put in hand early in 1936.It was intended to haul the whole mine output through this shaft, which was 1,600 feet from the mill then operating. An extensive conveyor system thus became necessary unless a new mill was built near the shaft. A careful study of the situation was made by the management and consideration was given to requirements for expansion, the condition of...

Jan 1, 1940

By George Wilkinson

"AbstractThe consistent relationship between the availability of electrical energy and our economic wellbeing is well known. As we develop the energy we need to nurture industrial civilization in decades ahead, we will at the same time reduce our reliance on dwindling supplies of oil and gas. Coal and uranium will be developed as our major fuel sources to meet medium-term. energy needs, followed by fusion and solar energy for the long term.IntroductionTHIS PAPER treats the matter of energy in a way that is quite different from that of the crisis-type atmosphere which surrounds so much of it currently in the news media. On the one hand, we lift the whole subject of energy out from its present-day involvement with short-term issues and take an important longer-term look at the solutions which lie before us. On the other hand, we recognize that short-term issues are important and, as we are reading and hearing, many of the right short-term solutions continue to elude our politicians, our policy makers, and even some of those with knowledge and authority in the energy field.A year ago, if you asked people how they would go about conserving energy, they would probably have said turn out the lights. They would probably say the same thing today, but they might also include other things such as driving the automobile more slowly or putting more insulation in the attic. However, their first impulse is still to use less electricity."

Jan 1, 1977

By Ross R

Although mining is an old industry its management is quite a new science, and its complications are now being recognised as demanding expert knowledge in many branches of technical and professional education. Not the least amongst these isaccountancy, for probably its most important problem is "How to control the expenditure." Unlike most businesses a mining company stands almost entirely in the light of a purchaser in the world's markets, and not as a seller, except say for product so the established and perfected systems of modern industries cannot be adopted for mining purposes. For this reason it has been left for late years to consider the matter seriously, and now a number of well-managed concerns have devised costs systems to suit their own requirements.Very little, however, has been published and even that is disjoined and difficult to make use of. Some of the costs systems in vogue, although elaborate and imposing, are not of very great value for keeping check on wasteful expenditure, or for displaying the commercial effect brought about 'by any particular change in practice, or by an addition or alteration to a portion of existing plant.

Jan 1, 1912

By Browner R, Lincoln F. J

The activity of silver in solid gold-silver alloys (electrum) has been measured with an electrochemical concentration cell based on the super ionic conductor silver-i3-alumina in the temperature range 200 to 80oaC.The measurements of the silver activity in the range 0.5 to 90.0 atom per eent silver were found to be highly reproducible although there is some disagreement with an earlier study which used a similar technique. At temperatures above 400° the silver activity exhibits both positive and negative deviations from ideality in the silver rich region.This method suggests a simple technique for the nondestructive determination of silver in electrum alloys.

Jan 1, 1983

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 E. Sun

Tailings disposal is a significant consideration for the mining industry, with the majority of the ore processed in most mining operations ending up as tailings. Several tailings dam failure accidents have occurred during the past few years and mine tailings dam failures are occurring at relatively high rates. Tailings dam failure is disastrous with the serious damage and the loss of lives. To increase the tailings dam safety, a tailings dam monitoring and pre-alarm system (TDMPAS) based on the internet of things and cloud computing platform has been accomplished with the abilities of real-time monitoring of the saturated line, impounded water level, rain fall and the dam deformations etc. The TDMPAS has been applied in several mines in China and helped the mine engineers monitor the tailings dam safety and get warning information automatically and remotely in any kind of weather conditions. This work has been demonstrated the tailings dam monitoring and pre-alarm system (TDMPAS) is meaningful to monitor the tailings dam physical safety condition. The TDMPAS could be applied to monitor all the national tailings dams online in the future.

Jan 1, 2012

THE Taranaki oil-field is situated on the western side of the North Island of New Zealand, at about its widest part, and may be said to be the most compact and fertile part of the Dominion, for, with the exception of the upper half of Mount Egmont and of the ranges adjoining, which absorb 36,000 acres, the whole of the area, minus what is taken up by the rivers and streams is suitable for settlement, and certainly two-thirds is good land. The gross area of the district is 2,417,299 acres. The principle rivers are the Wanganui, Mokau, Waitara, Patea and Waiwakaiho. Mount Egmont, which is 8260 ft. high, used to be called Taranaki, and from it the district takes its name (the Maori meaning of which is "sloping peak ").THE OIL-FIELDThe discription of an oil-field now-a-days usually resolves itself into a mass of figures and statistics, of great interest and value to the engineer and commercial man, but practically indigestible to the general public. It is the realm of the financierand the captain of industry.

Jan 1, 1912

By M. Karmis, C. Haycocks

The evolution of longwall mining is briefly traced from its inception in England in the 1620's. In the beginning this method recovered 90% of coal with roof closure controlled by packs and walls. Mechanization began with kerf cutting, crude face conveyors, and improved face support. Full face mining was accompanied by the introduction of self- advancing hydraulic supports. U. S. longwalls evolved a retreating system to recover blocks of coal outlined by room and pillar panels. Computer control combined with the most modern technology have greatly increased productivity. Past trends are used to predict future technological directions.

Feb 24, 1997

By A. S. Murphy, E. V. Manlapig, C. Green, J. W. Parkinson

Historically in Australia and the United States many coal mines deposited raw wash plant fines into large slurry impoundments. At the time the technology and market economics did not exist to make it viable to recover coal from these tailings. Today better technology exist to dredge and clean the tailings and there are circumstances where government regulations and market forces have come together to make coal recovery from these old tailings impoundments economically viable. This paper discusses the processes and equipment being used in tailings impoundment reclamation operations in Australia and the United States, and discusses the economic forces driving these operations.

Jan 1, 2001

The major technological advances of the last 30 years have profoundly reshaped mining practices. Machines keep getting bigger while productivity continues to increase and manning levels drop. These trends will continue and the introduction of breakthrough technologies will continue to accelerate, driven by a continued focus on lowering the cost of production, improving the productivity of workers and machines, and ensuring safer working environments. At the same time, global consolidation of mining companies has impacted on technology development in a range of ways. There are many potential technologies being proposed, some already operating in Australian mines. The automation of underground load-haul-dump (LHD) trucks for example, continues the process of removing workers from the most dangerous operating environments. Global positioning systems fitted to draglines, fibre optic communication channels, and 400 tonne trucks are only some examples of what lies ahead. However, where we need to return focus is to the technology of management û which is also one of the two key interrelated themes of this keynote address. Have we, as an industry, adequately been able to keep up with technological advances? Are our management systems as competent as the machinery we employ? The other key theme is the processes of globalisation and consolidation. What are the impacts on our industry? What are the implications of these processes, particularly for the ways in which we manage our people? My paper is divided into several components:some comments on the coal industry and the dramatic restructuring we have seen in recent years; in the context of this restructuring, an overview of my company and its evolution; my views on the role of contractors; some comments on the consolidation also occurring in the mining machinery and equipment, technology and services sectors; some observations on two major areas of technology û drill and blast; and trucks, shovels and excavators; the implications of consolidation and new technology for our employees and management; and finally some comments on research programs.

Jan 1, 2001

The rush for alternate iron-units in the last few years spurred a true outbreak of new alternate iron units projects many of them incorporating new process in what can be classified as the.most fruitful and innovative technology outburst, in the steel industry, in decades In a recent paper we focused on what would be, in our opinion, the ultimate targets of the use of alternate iron-units by mini-mills: 1. to improve quality, 2. to reduce cost, 3. to increase plant productivity, and 4. to improve `supplyability'. With these objectives in mind liquid hot-metal, among all possible scrap substitutes, has been proven to be by far the best. This conclusion stems from many different authors who have reviewed the `value in use' of hot-metal against other alternate iron units and measured its impact on steel-shop productivity and cost (Figure 1).

Jan 1, 1999