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By Rolfe PR, Ellis BA, Clements RJ

Associated Minerals Consolidated Limited (AMC) is constructing a 112,500 tonne/yr synthetic rutile plant at Narngulu, near Geraldton in Western Australia. Design of the plant is based on the technology developed by AMC and utilised in its two existing plants at Capel in Western Australia. Ilmenite Feedstock for the plant will be sourced from AMC's mine at Eneabba and coal obtained from the Collie deposits. The plant is scheduled to come on stream in the second quarter of calendar 1987. The rationale of the decision to construct the Narngulu plant is examined against the background of the world market for high-Ti02 content feedstocks. Also provided is a detailed description of the plant and an examination of the technology used in process Design.

Jan 1, 1986

In preparation of this Paper, the emphasis has been laid on the commercial rather than on the technical and scientific aspects of coal evaluation. It is intended to describe and comment on the principal factors which currently determine the selection and procurement of coking coal for the steel industry, and is not based on the results of any original research by the author. Evaluation of different coals for strictly thermal uses, for gas production or other chemical applications has not been attempted, and comparisons of coal with other fuels have been excluded: the paper is concerned only with coals for the production of blast furnace coke. The discussion is strongly related to, and illustrated by, British, and to some extent, other Western European practice, but it is hoped that the general conclusions may have a wider application.

Jan 1, 1975

This paper will describe the exploration project which led to the discovery of the La Escondida porphyry copper deposit in northern Chile and will serve as companion paper to the description of the geology of Escondida being presented by J M Ojeda. The author would like to express his appreciation to Robert Hickman, Chairman of Minera Escondida, for permission to present this paper.In July 1978, a proposal was made by J D Lowell to Robert Wheaton, then Exploration Manager of Utah International, that Utah fund a "grass roots" program exploring for porphyry copper deposits in northern Chile. Wheaton expressed interest, and it was agreed that Getty Oil Co also be invited to participate. A joint venture agreement for the Atacama Exploration Project was signed January 1, 1979, between Utah, Getty and Lowell. The project was managed by Lowell who reported to a management committee which through most of the project consisted of Lowell, Francisco Ortiz, Robert Wheaton, Maurice Young, Sigfried Muessig and Louis Rove. Oliver Warin and Jim Bratt participated in the committee in the last phase of the contract. Special thanks are due Louis Rove of Getty and Maurice Young of Utah who made contributions throughout the course of the project. Francisco Ortiz was resident manager through most of the project.

Jan 1, 1990

Different mineral structures can act as mineral reservoirs for the immobilisation of toxic compounds. In the paper different mineral structures will be explained and their potential for incorporation of heavy metals and anions will be shown. The following structures will be explained (P÷llmann, 2007):apatites (incorporation of heavy metals, silicate apatites);ettringites (fixation of oxo-anions);layered double hydroxides (fixation of heavy metals, fixation of anions, fixation of organics, sorption materials); andmanganese oxides. Different possibilities of solid solution and incorporation in crystal structures will be explained and advantages of stable minerals be proved using experiences with real toxic wastes. In the process of thermal treatment the formation of primary mineral reservoirs will be shown. The precursor phases (similar to well known cement minerals) react in contact with water to form secondary mineral reservoirs (cement hydration mineral products). The formation condition of primary and secondary mineral reservoirs and their stabilities and incorporation possibilities will be shown. Examples for incorporation of various elements are given. Application for water clarification will be outlined.

Jan 1, 2008

By Schoning W. L

Ore deposit models form the basis for numerous other economic decisions in the mining process. The success of these economic decisions therefore depend directly on the accuracy of the ore evaluation process. The Geology Department at the Sishen Iron Ore Mine is responsible for the generation of a reliable geological computer model of the rock material with predicted grades. This information is then utilised for further ore reserve calculations, mine planning, production scheduling and grade control. Owing to a very complex geological orebody, grades and beneficiation characteristics differ significantly from sample to sample. This means that ore evaluation is a difficult process and great reliance is placed on computer techniques. In 1993, preparation for the ISO 9002 quality certification of the mine motivated the Geology Department to hold formal `problem solving' sessions in order to identify and revise problem areas in operating

Jan 1, 1995

Water resources legislation in Brazil is evolving in a number ways. The nature of water resource ownership has changed in the last constitution (1988) so that now all water remains the property of the state and not the individual. There is also an increasing amount of legislation to control water access from the environment and regulation over water quality for water discharged. Finally, in some regions charging for water has been introduced and this is expected to become more wide-spread over the next few years. Increasing government attention to water legislation creates an increased need for mine sites to improve water management. As a fundamental basis for this, it is necessary to make robust estimates of mine site water balances, which also requires knowledge of the regional water balance to provide context for the mine water use. A conceptual model for mine site and environmental water balance is presented. Issues associated with conventional water monitoring are discussed. It is proposed that introduction of automated monitoring to provide comprehensive and consistent data is attractive. However, there remain a number of cultural and practical impediments to purchase, implementation and maintenance of effective monitoring, which are summarised.

Jan 1, 2009

By Kobayashi M

Particulate chalcopyrite samples (78 ~ 98 mole per cent chalcopyrite, screen size fraction from 710 to 250 µm) were prepared by crushing and sieving lump ore samples from 12 locations in the Mt Isa Mine. Measurements of thennoelectric power (which does not involve the passage of a current) were made using a packed bed that was compressed by loading with a weight and placed in a temperature gradienL Details of the apparatus are described.The effect of particle size was investigated by preparing 12 fractions, with mean particle sizes ranging from 605 to 2.2 µm, from one of the ore samples. Values of thennoelectric power decreased with both increasing particle size and loading pressure; however it remained fairly constant for particle sizes above 80 µm, when loading pressure exceeded 3.3 MPa.Measurements of the chalcopyrite samples gave an average value of -260 JlV/K (-248 ~ -268 µV/K) for nine samples and about -290 µV/K for three samples, showing that these samples were all n-type semi-eonductors.

Jan 1, 1990

By Carroll D. A

The mining and minerals industry has had and will undoubtedly continue to have a considerable impact on the development of this State. For the first 60 years of its history the colony of Western Australia made slow progress; its population in 1889 being only 43,000. However, as a-result of discovering gold at Coolgardie and Kalgoorlie the Eastern Goldfields alone had a population of 25,000 by 1897. The income generated by the gold mining industry allowed the Premier of the day, Sir John Forrest, and his Government to support the proposal put forward by the State's Engineer in Chief, C.Y. O'Connor, to construct a pipeline to carry water from the Darling Ranges to Kalgoorlie ; a distance of 600 kilometres. The demand for people knowledgeable in the science and art of mineral exploitation also prompted the State Government to establish a School of Mines in the Goldfields in 1902, where it has remained ever since. The gold mines of this region have been a major source of employment for over 70 years and there is no doubt of the fact that their continued prosperity minimised the effect of the world recession on Western Australia in the 1930's.

Jan 1, 1979

By Savidis G

The characteristics of 'Z' (Back-over run) and 'R' (Reverse) ventilation systems are dis- cussed in relation to their suitability for longwall mining. Experience in European mines has been described as a basis for comparison with Australian conditions. In assessing the merits of each ventilat- ion system, such factors as longwall layout (pillar design, number of headings and gateroad stability), the need for gas drainage and bleed- er systems, as well as the influence of seam dip have been considered relevant. The R system is generally applicable for single and two heading development in seams where gas emission is a less serious problem. In contrast, the lower extraction to development ratio of the Z system (which arises from using three or more heading layouts) is considered more favourable where high gas emission occurs. The Z system provides greater flexibility with respect to the provision of refreshing air at the tailgate end, access of men and materials, installation and retrieval of gas drainage systems and the ability to interchange main- gate and tailgate roadways in cases where roof strata loads are difficult to control, or where cpam in hac an influrnra

Jan 1, 1983

By J Ralston, G B. N Kaggwa, L Huynh

Three polymers of varying chemistries and molecular weights have been used to depress talc in a model sulfide ore consisting of talc, pentlandite, and chalcopyrite. Flotation testing revealed a distinct hierarchy of effectiveness of the polymers in the depression of talc (HP Starch > Polymer-H > Dextrin WY) but a different order of effectiveness for depression selectivity (Dextrin WY > Polymer-H > HP Starch). Adsorption isotherm determinations for the gangue and valuable mineral phases indicate that the differences in selectivity are partially due to adsorbed amount variations, with Dextrin WY adsorbing marginally less on the sulfides than Polymer-H. Contact angle measurements on packed particle beds have revealed that the polymers have differing abilities to reduce the contact angle of talc and the sulfide minerals. An explanation of the observed trends is given in terms of the binding mechanisms of the polymers on the talc and the sulfide mineral phases. Order of addition effects between collector and depressant were also investigated using adsorption isotherm determinations for the polymers in the presence of a pre-adsorbed layer of collector and vice versa. Adsorption of the polymers was not affected by the presence of the collector. Similar results were obtained for the adsorption of collector in the presence of pre-adsorbed layers of polymer.

Jan 1, 2005

A laminar-flow furnace was used to study the combustion of four flotation concentrates (chalcopyrite, pyrite, galena, and sphalerite) in air at temperatures up to 1400¦C. A special- Iv developed two-colour pyrometer was used to measure the temperature of individual chalco- pvrite and pyrite particles as they underwent combustion. Chalcopyrite and pyrite ignited with very high rates of reaction at air tempera- tures above 480 and 600¦C respectively, forming molten products. Galena and sphalerite required temperatures in excess of 700 and 1200¦ respect- ively to attain equivalent rates of reaction. The high rates of reaction for galena and spha- lerite were caused by vaporization. Temperature measurements for chalcopyrite and pyrite are reported here, together with vaporization measurements for chalcopyrite, galena, and Sphalerito

Jan 1, 1980

By J E. Lynch

The Mt Leyshon gold deposit produced in excess of three million ounces of gold and considerable silver over a period of approximately 130 years. Most of this production occurred between 1987 and 2001. Mining commenced in 1872, however it was highly likely that Chinese miners were not only removing alluvial gold from the area but were also mining very rich æreefÆ gold. Records for early alluvial and hard rock mining do not exist, however gold production was probably considerable. In the early 1980s Marathon Petroleum (Australia) Ltd (MPAL) joint ventured into the Mt Leyshon area which had been held as a mining lease by Noranda Australia Ltd since 1968. Noranda at that time was concentrating its exploration effort on the Balcooma base metal prospect areas to the north of Charters Towers. In early 1982 MPALs parent company was taken over by US Steel. This led to an opportunity for MPALs Australian management to purchase all tenements and licences (except for coal, oil and gas) which were duly purchased for $US 1 million. At this time MPAL had a remarkable array of gold tenements (many of which were subsequently mined by other companies) and Mt Leyshon was considered to be the highlight. Early æseedÆ capital ($A 3.1 million) was raised with backers being the Bank of America, the NSW Government Superannuation Scheme, Westpac, private individuals and a Queensland grocery chain by the name of æJack the SlasherÆ.

Jan 1, 2004

By Bin H

East Guangdong tin province overlaps the southmost part of the mesozoic magmatic arcof continental margin type in Southeast China and is dominated by mesozoic syntectic magmatism,which associated to tin mineralization. It is distinguished from Nanling tin province but quite close to NW Bolivian tin province in both tectonic and magmatic relations.Tin deposit's mostly of cassiterite-sulfide, cassiterite-silicate formations are localized along exsocontact zone of granitoid batholith or stock, boundary area of volcanic depression, or, within volcanic edifice. Petrochemistry studies show tin was concentrated as intermediate-acidic magma evolved by fractional crystallization. Xiling tin deposit of vein type related to extrusive... the lava dome was formed at T C 221-301 and at very shellow depth,seems to correspond to type A in classification for Bolivia tin deposits by J.N.Grant. Tashan tin deposit of dissemination type related to hypergene intrusive facies,with mineralization occured in endocontact zone of granite porphyry dykes is considered as porphyry type,which spported by H-0 isotope and gas-liquid inclusion evidences. It formed at T C 250-430, comparable to Bolivia porphyry tin deposits,but at a greater depth 1.3 3.0km.A model for known tin deposits in East Guangdong was worked out. A good prospecting perspective was revealed for the potential type of tin deposit in East Guangdong--subvolcanic porphyry tin deposit.

Jan 1, 1990

In line with the recommendations of The AusIMM/AMIC Joint Committee Report in 1981 Isa Mine ore reserves are quoted in proven and probable categories (recoverable ore reserves). Internal reporting considers geological mining and extraction reserves in terms of proven and probable categories. Proven reserves are subdivided into detailed and confirmed ore. External reporting includes a possible ore category (not a reserve). The basis for these divisions is the spatial distribution of sampling data. Proven ore is defined by data 80m apart or less and probable ore by data 80m to 150m apart. Within the proven ore category detailed ore is defined by data 40m apart or less and confirmed ore by data 40m to 80m apart. Kriging is used to provide tonnage and grade information for the currently producing 1100 and 1900 orebodies. Kriged cross sections are initially produced to coincide with existing geological sections and are used for stope design. Stope ore reserves calculations are ideally performed at three discrete design stages, which in order of increasing accuracy are: preliminary design (PD), final design (FD) and ring design (RD). At each of these stages Kriged meshes incorporating the most recent sampling information are produced for reserve calculations. Historically derived mining and extraction factors are applied both to global reserves and individual stope reserves to reflect changes in geological and mining conditions as well as the sequencing of extraction. These factorised reserves are then inserted into the computerised reserves inventory system (RIN). Monitoring of individual stope performance continues into the production stage with input from planning, research, survey and production personnel. This allows actual extraction factors to be derived for comparison with predicted factors, providing some measure of stope performance.

Jan 1, 1987

For several decades miners have been obliged to maintain a vast supply of sharp steels at the working face to meet the hungry needs of rock-drills. In medium and large size mines this has meant the setting up of an organisation to store steels, to make and sharpen bits with all the complication and skill of forging, hot milling and heat treatment, and to transport sharp and dulled steels to and from the working face with all its labour, wastage, and inconvenience to other mining operations.In a mine with 250 rock-drills in use, a flow of more than 60,000 sharpened steels each month has to be maintained to keep the machines fully employed, so some idea of the magnitude of this problem may be grasped.For a long time it has been apparent that it is mainly the bit itself that wears, and many attempts have been made to reduce the enormity of the problem by providing detachable steel bits which could either be used once and rejected, or sharpened three or four times before rejection.At the same time metallurgists have striven to 'improve the quality of the steel and the heat treatment afforded it so that a bit, readily workable In a normal mine drill-shop, could be produced having a high resistance to wear and fatigue; but, although various alloy steels have been marketed, it is still usual to find many mines relying on a "straight" carbon (0.6 - 0.9% C.) steel for their drill steels.Since 1915 increasing use has been made of tungstencarbide as a cutting implement in the engineering industry. Where, on account of its great hardness and long life, it...

Jan 1, 1948

By Millett R

In January 1989, Western Mining Corporation (WMC) acquired the Perseverance and Rocky's Reward orebodies and associated infrastructure from the Agnew Mining Company (AMC). AMC had closed the operation in August 1986 and it had been on care and maintenance since that time. To return the operation to full production as quickly as possible it was planned to mine the Rocky's Reward orebody by opencut mining and treat this ore whilst the underground Perseverance workings were rehabilitated. Removal of overburden from Rocky's Reward thus commenced immediately with a target of April 1989 for delivery of the first ore to the concentrator. Extensive rehabilitation and upgrading of the concentrator commenced in late January, and continued in stages for an 18 month period. The first stage consisted of overhauling all existing equipment and completing a crusher upgrade commenced by AMC prior to the mine closure. During this period, it was necessary to recruit a workforce and re-establish all the required support structure. In late April the plant commenced commissioning trials on mullock. The first ore was crushed on the 11th May 1989 and concentrate produced the following day. From May 1989 to June 1990 the plant was producing nickel concentrate whilst further upgrading continued. During this period, the flotation capacity was tripled by installation of a bank of eight Wemco 144L flotation cells in rougher-scavenger duties and two 12 metre by 2 metre diameter columns in cleaning duties. The existing vacuum drum filters were replaced by two Larox PF32 pressure filters, eliminating the need for solar drying and allowing the flash drier to be fed direct from the filters. These, along with a major borefield expansion and further work to the crusher increased the nominal plant capacity from 600,000 to 1,000,000 t/yr. The plant achieved the 1,000,000 t/yr rate in April 1990.

Jan 1, 1991

The results of a systematic geochemical survey of rare elements are applied to elucidate genetic relations in a suite of rocks and to predict the probability of mineralization. The geology, radioactivity, major element geochemistry and classification of the main intrusives are described. The distribution of a group of rare elements, their concentration trends and the bearing these have on the emplacement sequence of the rocks are considered in some detail. The guides for exploration in the Pilanesberg that emerge are listed and some areas which substantiate predictions are described briefly. It is concluded that a study of rare element trends can make a considerable contribution as an exploration tool and for clarifying relations between the members of rock suites.

Jan 1, 1986

Water retention, water loss and delay in tailings storage rehabilitation are major challenges for many Coal Mines. Work by Stewart, Backer and Busch in the early 1980s suggested that there were improvements to be made in tailings dewatering and density by the addition of flocculant. This prompted ACARP, in cooperation with Bulga Coal Management (Xstrata), to initiate a research project investigating the impact of flocculant addition on tailings deposition density, water retention and the tendency for tailings to form surface crusts suitable for subsequent rehabilitation. A polyacrylamide-based flocculant (200 - 250 g/tds) was injected into the tailings line immediately prior to disposal into the impoundment area. The flocculated slurry rapidly released clear water and created a beach due to the immediate increase in deposition density. The deposition density increased from 35 per cent w/w to 61 per cent w/w solids within 24 hours and continued to increase to 75 per cent, seven days after treatment. The water capture at the tailings storage facility improved by more than 90 per cent; water which would otherwise be lost from the circuit through retention and evaporation. The impoundment capacity had nearly tripled due to the improvement in initial deposition density from 420 kg/m3 up to 1163 kg/m3. Four weeks after disposal surface crusts were forming on the storage facility, suggesting that there would be less delay between cessation and tailings storage rehabilitation.

Jan 1, 2008

By J Austin, R Bitencourt

Differences between the long-term model (LTM) and mine geology system (MGS) grade control block-outs on a blast block scale can impose difficulties to planning crusher feed grade and tonnes on a monthly to weekly blend basis. Detailed geological input to short-term planning has been integral to improve the performance and reduce risk in six-week to three-month production schedules and local variability in tonnage and grades is often not accurately represented in the LTM. The challenge of producing to combined target specifications from different mine sites in an integrated mine to ship business has been reduced with the creation of blast blockout-based short-term model. These short-term blast block models (STBBM or STM) are robust predictive tools created for upcoming benches of current mining areas by firstly collecting data from the pit in the form of bench and face mapping and projecting the structure and stratigraphy down to the next bench. A wire-frame of the projected contacts based on material destination from production blockouts is created and then checked against the LTM. Blast block data from the bench above including assay results and material logging is extracted and validated according to the projected wire-frames (geozones). Individual blast blocks and a full block model are created for each bench production defined by the STP (bench plans). Data output from the STM is in a compatible format for import into scheduling specific software packages. Additional information is incorporated into the STM to allow querying of drill penetration rates, predicted powder factors, material hardness and feed type to further aid in the production planning process and cost forecasting. To date, reconciliation of the STM has been pleasing and certainly an improvement on the LTM, especially in areas where variability is higher due to geological complexity. Short-term predictions derived from in-pit geological observations allow mine planners to more confidently decide on mining block sizes and schedule tonnages and grades, reducing the risk component attached to developing production schedules based directly upon long-term orebody models and mine plans.

Jan 1, 2005

By Carter A. C

The increasing need for alternative energy sources as well as the less clearly perceived but equally increasing demand for non-fuel minerals has resulted in extensive exploitation of near surface deposits. Many such deposits have depleted reserves and mining corporations are increasingly turning their attention to deposits, with thicker overburden, less competent materials, steeper dips and more complex structure. These deposits pose mine layout, geotechnical and equipment problems as well as the need for large outputs to achieve economies of scale. The paper describes the major problems and operational solutions for such deposits using continuous excavation and transport equipment.

Jan 1, 1980