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Particle Size Measurement of TiO2 Nanoparticles in Non-Aqueous Solvent by Interactive Force Apparatus Under an Electric Field

Sep 13, 2010

By W C. Burton, J S. Kuszma, T O. Aspinall

The environmental impact of mining and evolving environmentallegislation has received increased attention worldwide in the last two decades (Bradfield, Shultz and Stone, 1996). The potential impacts associated with unstable spoil dumps from mine operations is the focus of concern both by the mining industry, environmental regulatory agencies and members of the public. Engineered slopes of mine spoils may be stable at the end of construction, but they can deteriorate over time. There is thus the need to increase the base of knowledge on the existing practices of spoil dump design and rehabilitation. Efficient engineering design and systematic economic evaluation of spoil dump reshaping techniques for mine rehabilitation assists in maintaining the expected standards of environmental compliance. As part of the overall approach for effective engineering design ofspoil dumps, a comprehensive, computational and efficient tool isrequired for assessing the economics and productivity of existing spoil dump reshaping practices for efficient mine rehabilitation. Such a design tool is useful in linking current spoil dump environmental management practices with engineering design planning and economic impact evaluation. This paper identifies the processes for the economic impact evaluation for existing spoil dump reshaping practices and proposed final site dump designs. Selection of an efficient spoil dump design at optimum costs will ensure operational efficiency. A case study is presented identifying economic impact evaluation in earthmoving equipment selection and the costs involved for the reshaping of spoil dumps to that of varying final site designs.

Jan 1, 2000

By D J. Holden

Prospectivity, the relative value of gold, investor confidence, general economic stability and legislation driven by public attitudes are seen as the major influences on the gold mining industry in New Zealand. Since the 1860s the gold mining industry in New Zealand has been subject to the complex interaction of these influences resulting in three successive boom and bust periods. The booms are related to periods of greatest potential economic growth. The busts are more strongly related to downturns in the economy and falling gold price. The influences may be expressed as trends over time. The role of gold has changed from being a currency base to that of a traded commodity. This change has caused price instability and rapid fluctuations in its value. Increased competing land uses, shifting public attitudes and legislative changes have added to the instability of the industry. Reaction against change is to be expected from the companies until new legislation is seen to be functioning efficiently. Other trends show that there has been a tendency towards reduced exploration and consolidation of active gold mining projects. The future consequences of this are likely to be felt both regionally and nationally as there will be no new discoveries to fill production voids which will develop as currently producing mines close. The review of New Zealand's resource use statutes is nearly complete. A period of legislative stability can now be expected. There are some positive signs that consents will be obtained much more quickly than under previous legislation, particularly by those companies which develop the skills to work with the system. The new regime is about consideration of impacts rather than specific activities. This, together with excellent prospectivity, bodes well for the identification of mineral resources in New Zealand.

Jan 1, 1992

A continuing demand for exploration geologists, at a level well below that during the mineral "boom" of 1967-1971, will be highly selective. The exploration geologist must be more than the traditional geologist whose primary function has been detailed description of rocks and their recording on a geological map. He must be capable of 1. reconnaissance recognition of favour= able environments for ore mineral concentrations, 2. application and interpretation of techniques of search and evaluation, and 3. evaluation of economic, technological and political interactions that combine to make an ore deposit. Universities have an obligation to their students to provide them with a saleable skill, to educate them so that they can cope profess- ionally and socially, and to provide a mechan- ism by which education can be a continuing process. Humanistic and social studies, develop ment of communication skills, understanding of economic and management principles, ability to assess rock properties that influence extract- ion and beneficiation, and a knowledge of technological developments and limitations are necessary parts of the exploration geologist's

Jan 1, 1974

Study on Oil Agglomeration Flotation for Deinking

Sep 13, 2010

The introduction of gravimetric sampling of respirable dust in the mining industry ne- cessitated the standardisation of techniques. The paper reviews the legislation con- trolling respirable dust monitoring for risk assessment purposes, it discusses the actions taken to introduce gravimetric sampling in collieries and it summarises the proposed guidelines. In conclusion, some of the results of dust surveys conducted in accordance with the proposed strategy are discussed.

Jan 1, 1988

By Met B. E

During the operation of the Parkes process of desilverising, and in the earlier days of the continuous process, gold and silver were removed separately from softened lead bullion. Gold was removed in the Parkes process by a selective zincing, and -in the continuous process by treatment with zinc in a special de-golding kettle, in each case a crust being obtained carrying the gold and a small portion of the silver. Actually the process could have been more correctly termed a de-copperising process, on accountof the relatively large amount of this metal present, and its affinity for zinc, which caused it to enter the crusts produced.The crust was treated in reverberatory furnaces, where the bulk of the copper and zinc was removed in by-products, and the resulting "gold bullion" cupelled to give adore bullion containing approximately 2,000 ounces gold per ton.For the purpose of parting this dore, a small Balbach-Thum plant of 11 cells was used, and once each six months a short campaign was conducted on the accumulated metal.With the development of the process of de-copperising smelter bullion by means of sulphur, when a bullion averaging about .004% copper was constantly available for refining, the need for a separate de-golding process disappeared.The de-golding kettle of the Continuous Process...

Jan 1, 1937

By R G. Reddy, Z Zhang

Viscosities of CaO-aluminosilicate ternary melts were estimated using a structure-based model. The model considers depolymerisation effects and related breakdown of the silicate network structure on the addition of metal oxides to the melts. The predicted values are in good agreement with the experimental values over the whole temperature and composition range.

Aug 21, 2024

By S Telford, J Weir

Heathgate Resources Pty Ltd (Heathgate) operates the Beverley Uranium Mine in South Australia, located on the plains between the northern Flinders Ranges and Lake Frome some 600 km north of the state capital Adelaide. The uranium orebody exists in permeable sands within the confined, highly saline Beverley aquifer, approximately 125 m below the ground surface and the uranium is mined using in situ recovery (ISR) technology. The Beverley mine is a highly technologically advanced ISR mine and is operated in accordance with stringent safety and environmental standards. The mine is currently licensed to export 1500 t of uranium oxide (U3O8) per annum. This paper outlines the fundamental differences between ISR operations and the more traditional uranium production methods, such as agitation leaching and heap leaching, where the ore is removed from the deposit, stockpiled, crushed, milled and leached on the surface. Solids tailings from either the mill or the heap are finally deposited in a tailing storage facility. ISR mining differs from conventional mining because the ore remains in place underground (in situ) and the groundwater contained in the ore-bearing aquifer is utilised as the mining fluid. This is achieved by drilling into the deposit and installing wells for extracting and re-injecting the groundwater which is fortified with chemicals. The fortified groundwater (ie mining fluid) flows through the permeable sands containing the orebody, dissolving the uranium. The pregnant mining fluid is then collected and transferred to the recovery plant where the uranium is captured (on ion exchange (IX) resin in the case of Beverley). The barren mining fluid is then re-fortified and recycled to the wellfields. Once mining is completed in a wellfield, the surface infrastructure is relocated to a new wellfield, and the mined-out wellfield is rehabilitated to its original surface condition. A comparison of 'standard' hydrometallurgical plants, heap leach and ISR shows a number of key differences, such as the rate of leaching, the level of control available to the operators, and the type of contact/reaction that occurs. While limited in its applications, ISR mining has proven successful at Beverley and provides another mining and processing method for the production of uranium.

Jan 1, 2008

By R L. Braithwaite

Mesothermal quartz lodes in Paleozoic Greenland Group metasediments of the Reefton area have produced 67 t of gold up to 1951, and recent exploration has identified new gold resources in several deposits, including the largest past producers, Blackwater and Globe Progress. The metasediments consist of alternating sandstone and argillite, metamorphosed to lower greenschist facies and hydrothermally altered near the quartz lodes. We examined and sampled drill core from four prospects, Globe Progress, General Gordon, Merrijigs and Blackwater, to determine the mineralogical and geochemical characteristics of hydrothermal alteration in the sandstone units. The sandstones are feldspathic litharenites averaging Q65, FlO and R25, with detrital grains of quartz, feldspar, rock fragments, muscovite, biotite (mostly altered to chlorite), and trace quantities of graphite, apatite, zircon, tourmaline and titanite. Hydrothermal alteration has developed a secondary mineral assemblage of K-mica (muscovite, sericite and illite), carbonate, chlorite, pyrite, arsenopyrite and limonite. The abundance of secondary chlorite is greater at Blackwater than at the other locations studied. Features in the sediments associated with increasing hydrothermal alteration towards quartz lodes include, the development and increasing intensity of colour bleaching and carbonate spotting, increasing quantities of disseminated pyrite and arsenopyrite, and the appearance and increasing quantity and size of thin carbonate, quartz and sulphide veins. This is accompanied by increasing concentrations of sulphur, arsenic and antimony as shown in assays, and of volatiles (loss on ignition) and iron as seen in XRF analyses. We were unable to identify consistent trends in the behaviour of potassium, sodium, and calcium that are exhibited by similar mesothermal quartz lode deposits inVictoria, Australia.

Jan 1, 1998

Mining projects have long since presented challenges for the protection of the water environment. Lessons learnt from historical pollution incidents and increasingly stringent environmental controls have significantly improved the environmental performance of mines in developed countries. In contrast, water protection legislation and guidance in the Former Soviet Union (FSU) countries, based on the æpolluter paysÆ principle, has not promoted the prevention of water pollution, and examples of poor environmental performance in mining still exist. However, there is now evidence of emerging legislation encouraging the protection of the water environment. This paper provides an overview of water protection legislation in the Russian Federation and Armenia and highlights some of the challenges facing international mining companies developing projects. A mining case study is described, which highlights how communities in Armenia increasingly value their water environment. Here, greater public participation in development projects is playing a vital role in influencing water protection legislation. It is considered that public opinion and emerging legislation will increasingly present challenges for the development of mining projects.

Jan 1, 2006

By Gill L. F, Gleeson HB

This paper describes the development of a Computer Aided Design and Drafting based mine planning system in the State Electricity Com- mission of Victoria. The system combines a commercially available CADD system with a commercially available mining/geological package. The methodology used in the establishment of the combined system, the fea- tures of the system and the current status of development are discussed.

Jan 1, 1989

By T Y. Ko, Y S. Kang, S J. Park, J H. Hwang

The lunar subsurface, particularly the lava tubes formed by ancient volcanic activity, presents a promising environment for establishing safe and sustainable human habitats on the Moon. Tunnel Boring Machines (TBMs), widely used for excavating tunnels on Earth, offer a potential solution for developing these subsurface spaces. However, the unique lunar conditions, including extreme temperatures, high vacuum, radiation, and the extraordinary strength and abrasiveness of lunar rocks, necessitate significant adaptations to existing TBM technology. This study investigates the feasibility of utilising TBMs for lunar subsurface exploration and base construction, addressing the challenges posed by the harsh lunar environment. We review previous conceptual designs for lunar TBMs, highlighting their strengths and limitations in addressing these challenges. Additionally, we explore innovative excavation methods, such as microwave-assisted rock weakening and undercutting techniques, to enhance the efficiency and effectiveness of lunar TBM operations. By evaluating the geological characteristics of the lunar crust and analysing the potential of lava tubes as launching points for TBM operations, this study provides a comprehensive assessment of the technical requirements and operational considerations for lunar TBM implementation. The findings of this research contribute to the growing body of knowledge on lunar base development and pave the way for future human exploration and utilisation of the Moon’s subsurface resources.

Sep 1, 2024

A general outline of the significant features in the quality and manufacture of the more common refractories is given. Where possible, linkage between quality development and control and service applicationhas been shown and explained. INTRODUCTIONThe refractory industry is no stranger to change. New processes and revision of old processes in other industries are the harbinger of new and revised products in refractories.Few of the changes are dramatic; generally they are evolutionary rather than revolutionary. New developments are additional to, and inclusive of, established practice.Therefore in this paper it is necessary to repeat much of what is already known in order to show the development taking place.FIRECLAY REFRACTORIESGeneral technology Fireclay refractories are the most common, the most varied and the most versatile of all refractories. Virtually any composition of silica and alumina up to the composition of kaolin is possible. For purposes of comparison they may be classified in the Continental fashion in accordance with chemical composition or in the American way according to "duty". That the two methods are equivalent is shown by an inspection of the alumina-silica diagram of Bbwen and Greig (1924). 'Fireclay refractories are composed of a glassy and a crystalline component derived from the chemical and physical nature of the raw materials used in their manufacture.

Jan 1, 1961

Differences in the assay results of replicate samples engender doubts on the reliability of ore sampling and of assaying procedures. An analysis of variance is a technique to estimate the variability at each level of the procedures. In an example, the variability of one-metre core samples was far greater than that of the assaying technique.

Jan 1, 1976

By B D. Sowerby, N G. Cutmore

Improved process control can be achieved through the accurate and reliable on-line measurement of critical process parameters in real time. Over the past few decades on-line analysis techniques have been developed and applied in the mineral and energy industries for the measurement of process stream composition, mineralogy, particle size and flow rates. This has led to increased throughput and product quality while reducing processing costs and minimising emissions. The support of a sustainable mineral processing industry will require the further development of on-line analysis and control technologies. The application of developments in instrumentation combined with improved control strategies will lead to improvements in process efficiency resulting in large economic benefits to the industry, reduced energy usage and lower process emissions. There is a clear convergence of interests in being able to better measure and control minerals processing in terms of the triple bottom line of economic, social and environmental impacts. Technology is increasingly becoming available enabling measurement across the entire spectrum of minerals processing from mining to hydrometallurgy and pyrometallurgy. CSIRO is developing a range of these new technologies. A number of these developments are discussed in the present paper, namely: on-line particle size analysis and acoustic emission methods to enhance the control and optimisation of grinding circuits; on-line mineralogy of dry powders and slurries; on-line bulk elemental analysers for application on conveyor belts and in smelters; and the development of new sensing technologies for sorting base metal ores.

Jan 1, 2002

Gippsland has perhaps the most colourful history of exploration of any area in Australia. Hydrocarbons were first discovered in the Gippsland Basin in 1924 when a water well at Lakes Entrance encountered oil and gas shows. In 1942, the Commonwealth and Victorian Governments, in an effort to supplement a wartime oil shortage, sank a shaft near this well and produced 8000 barrels of low gravity oil up to 1956, when the field was abandoned. A total of 64 shallow wells had been drilled in the Lakes Entrance area by that time. Elsewhere in the onshore Gippsland Basin, 30 wells were drilled from 1925 to 1941. In 1960 BHP Ltd was granted an exploration permit covering much of the offshore area of the Gippsland Basin. Esso Australia Ltd joined BHP in 1964 and drilled the Barracouta-1 gas discovery in 1965. Since then over 100 exploration and appraisal wells have been drilled in the basin resulting in the discovery to date of some 3.6 billion barrels of recoverable oil and 8.8 trillion cubic feet of recoverable gas (Current remaining recoverable reserves are 906 million barrels of oil and 5.7 TCF of gas). Exploration in the offshore areas is actively continuing today and new discoveries are still being made.

Jan 1, 1992

By J Kinal, P Steinier

A considerable volume of work exists in the literature examining the electrochemical interactions between grinding media and sulfide minerals. Broadly, most sulfide minerals are more noble than forged steel grinding media used during comminution, therefore a galvanic couple between the media and the sulfide mineral(s) exists, which increases the corrosion rate of the grinding media. The corrosion products of the grinding media, iron oxy-hydroxide species, invariably precipitate on to the surfaces of the sulfide minerals thereby affecting their floatability. This paper explores the science behind these corrosion reactions, and provides an explanation of their impact on the pulp chemistry of sulfide mineral slurries and subsequent flotation behaviour. A number of laboratory and plant case studies are used to illustrate the benefits of changing to a more inert grinding media.

Jan 1, 2005

Two small coral islands in the Pacific Ocean, situated close under the equator, and formerly classed among the Line Islands, have, during the last three or four years risen into prominence owing to the valuable deposits of phosphate of lime discovered on them.The deposits of Ocean and Pleasant Islands are under the control of the Pacific Islands Company (1902) Limited, of London and, Sydney, and the high grade of the phosphate, together with the exceptionally favourable facilities for mining this mineral, of which there are several millions of tons on these islands, give this company advantages which enable them to command the Australian and New Zealand markets, and also to make large contracts with Japan and other countries. Both islands, as far as surface indications are concerned, are entirely constructed of coral, with phosphate on the top from the highest points to the present sea level, there being no sign of volcanic rocks, with the exception of a few pieces of drift pumice on the coast.Banaba (Paanopa according to. the Admiralty charts), also known as Ocean Island, was discovered in 1804. It is situated in lat. 0° 52" S. and long. 169P 3[)" E.

Jan 1, 1904

The Purification of Low-Grade Quartz Ore by Flotation and its Mechanism

Sep 13, 2010