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The usual metallurgical, engineering and administrative activities associated with the handling and smelting of ores, and the subsequent handling and treatment of the products of smelting, present also problems of hygiene that engage the earnest attention of executives in all well-managed concerns.Again, associated with the employment of any considerable number of men, there is always present the problem of accident prevention.INDUSTRIAL HYGIENE.In the earliest records of lead min.ing and smelting there are references to the injurious effects of lead oh the health of the employees, and, with the advancement of medical science, lead poisoning has been the subject of many works by various authorities in many countries.Moreover, in practically every civilised country, there are laws governing the conduct of the lead industry, and in most cases these laws stipulate that employees shall receive compensation for disability caused by lead poisoning.This provision gives the problem an economic aspect. Apart from the legal and the economic aspects, however, there is the humanitarian aspect, which implies that the...

Jan 1, 1937

Flat jack stress determinations in selected colliery roadways have revealed a range of measured stress from 330 lb/sq. in. tension to 3,750 lb/sq. in. compression. Photoelastic examination of loaded plastic and actual rock model mine openings has shown that the primary horizontal stress required to attain these measured stresses would be from one to three times the superincumbent vertical load.Examination of roof movement with a borehole extensometer and a series of anchors at various horizons to 30 feet in a vertical roof borehole showed that when a standing face was advanced the roof movement was practically confined to the lower two feet. The majority of this movement occurred during the 36 hours after mining at this face commenced.The use of a radioactive isotope and a scintillation counter in a pair of parallel boreholes is a sensitive and accurate method of roof bedding plane crack detection.INTRODUCTIONA knowledge of strata stresses is required to understand the deformation of an underground opening and, in particular, the roof behaviour. It is the aim of investigations currently being conducted by Australian Coal Association (Research) Ltd. to determine the stress existing around mine openings and the location and magnitude of roof movement.STRATA PRESSURE MEASUREMENTMost measurements of strata stress are performed at the surface of underground openings and the majority measure the change of strain resulting from stress relief. The accuracy of the measured value of stress depends upon knowledge of the rock modulus of elasticity. The flat jack method has the advantage that strain relief is restored by a measured stress applied directly by the jack. The rock modulus of elasticity can also be determined.

Jan 1, 1963

The concentration of Mt. Morgan sulphide ore has always been attended by serious loss of gold. Until recently, with a simple selective flotation flowsheet, even the lowest grade of ore milled-about 2 dwt. per long ton-thislloss was 0·9 dwt., whilst for average to high-grade ore, 3·5 to 5 dwt., the figure was 1·5 to 2·0 dwt. Early in 1937 it was decided to equip the research laboratory for an investigation into the condition and location of the escaping gold and the physical and mineralogical barriers preventing its recovery.With the completion of: this equipment in July 1937, trial and error testing, which had been explored to exhaustion, was abandoned and a five months' research programme mapped out and commenced. Based on the knowledge so gained, a flowsheet combining primary desliming, bulk flotation of the natural slime, selective flotation of the deslimed fraction, and cyanidation of the selective flotation tailing was drafted and tried with encouraging results in a 70-lb. per hour pilot plant. This flowsheet, modified to meet current circumstances, is being dove-tailed into the existing 1,500-ton sulphide ore concentrator, though the cyanidation treatment is actually carried out in the oxidized ore mill, to which the flotation tails are pumped.RESEARCH EQUIPMENT(1) Five tube elutriator (Fig. 1) t built in the company's workshop.

Jan 1, 1939

The production of sulphuric acid at Port Pirie by the contact process began in March 1924 with the commissioning of the Electrolytic Zinc Co.'s roasting and acid plant. This plant, operated by B.H.A.S. Pty. Ltd. on behalf of the E.Z. Co., continued to produce sulphuric acid from the gases evolved when roasting Broken Hill zinc concentrate in mechanically rabbled furnaces until September 1954, when the plant was closed down.In this peri9d of approximately 30 years some 600,000 mono tons of 98·5 per cent sulphuric acid was produced, most of which was used for fertilizer production at Wallaroo and Port Adelaide. During World War II 14,400 mono tons of the above was produced in the form of 20 per cent Oleum and railed to the Salisbury Munitions Factory for use in the production of nitro-glycerine, gun-cotton and T.N.T.In the early post-war period various ways of converting at least some of the sulphur in the gases' discharged to atmosphere from the lead sintering plant were considered until, in 1949, it was decided to erect a modern contact acid plant. Much work remained to be done on the roasting plant to produce a gas of suitable grade for the contact process and also on the design of a purification section suitable for the treatment of D.L. gases.The acid section itself, however, was largely of conventional design and it was therefore decided that this would be erected first. To it was then attached a sulphur-burning section to allow it to operate as a "hot gas" brimstone acid plant until the roasting and gas purification plants had been designed and erected. In this way the urgent need for sulphuric acid in the fertilizer industry would be relieved, to some extent at least, as soon as, possible.

Jan 1, 1956

CrusherMapperTM - A New Tool for Crusher Condition Monitoring The efficiency of mineral processing plants is entirely dependent on the availability of the plant equipment critical path. This typically concerns comminution circuits consisting of primary crushers and primary grinding mills. Crusher and mill availability are determined by the frequency and duration of maintenance shutdowns, which are primarily driven by the need for replacement of sacrificial liners. The change of crusher and mill liner shape over respective life cycles also strongly affects plant efficiency. It is therefore highly desirable to accurately monitor the condition of mills and crushers in order to optimise plant efficiency through maximised availability and targeted liner shape. Traditional comminution liner and other production parameter condition monitoring has been attempted through ineffective methods which prevent satisfactory management of crusher and mill maintenance and reduce operational control. This situation has recently dramatically improved for grinding mills through the development and commercial deployment of MillMapperÖ, a technology based on three-dimensional laser scanning data and dedicated software (Franke, Lichti and Stewart, 2006; Franke and Lichti, 2007; 2008; Franke, 2008; Franke, Redman, Johnson and Michalek, 2009). At the time of writing in late 2009, MillMapperÖ is in successful use at a rate of approximately 170 surveys and associated reports per annum at processing plants in Australasia, South America, North America and Africa. This paper presents the introduction of CrusherMapperÖ, the MillMapperÖ equivalent for crushers. CrusherMapperÖ also utilises high density, high accuracy laser scanning data, and features dedicated algorithms for three-dimensional monitoring of wear on crusher concaves and mantles. This facilitates the detection of wear hot spots or zones or localised liner failures, and accurate forecasting of reline tonnages and dates. It also for the first time provides the means to establish optimised concave and mantle shapes in order to achieve production targets. In contrast to any other currently utilised condition monitoring method, CrusherMapperÖ data collection can occur remotely and does not require any shutdown or crusher isolation. This method therefore does not interrupt crusher production while at the same time eliminating any confined space risk normally associated with taking measurements inside the crusher cavity.

Sep 13, 2010

Exploring the Breakage Environment in Mills with Discrete Element Methods

Sep 13, 2010

By C M. Wawryk, S L. Garwin, J D. Foden

"An EXTENDED ABSTRACT is available for download. A full-length paper was not prepared for this presentation. The Batu Hijau porphyry Cu-Au deposit in south-western Sumbawa, Indonesia is an ideal natural laboratory to study the fractionation of iron isotopes in magmatic rocks that range in composition from basaltic andesite to tonalite. Intrusive rocks are associated with a porphyry system that contains well-preserved early hypogene copper mineralisation. We analysed pre-, syn- and post-mineralisation igneous intrusive rocks. We also separated magnetite, chalcopyrite and bornite from hypogene porphyry-style quartz veins, and measured the Fe-isotope ratios of samples by solution multi-collector ICP-MS. Iron isotopic composition of samples from the magmatic suite show an increasing d57Fe with increasing SiO2, supporting geochemical and textural evidence that the Batu Hijau Tonalites underwent closed system fractionation. Equilibrium and co-existing mineral textures allow the calculation of the following preliminary empirical mineral-mineral fractionation factors at 500°C for certain mineral pairs.Iron isotopes have the potential to provide geothermometric data to complement fluid inclusion data, especially where heating stages have operational limitations and where fluid boiling results in a wide variety of inclusion types that may make analysis difficult.CITATION:Wawryk, C M, Foden, J D and Garwin, S L, 2015. Iron isotope fractionation in magmatic-hydrothermal minerals – a porphyry copper case study from the Batu Hijau deposit, Sumbawa, Indonesia, in Proceedings PACRIM 2015 Congress, pp 389–396 (The Australasian Institute of Mining and Metallurgy: Melbourne)."

Mar 18, 2015

The C.S.A. copper-lead-zinc mine, located 7 miles north of Cobar in central-western New South Wales, is the largest known mineral ocurrence in the Cobar mining field. The generally discordant orebodies occur within a strike width of 600 ft and an overall strike length of 1200 ft. They are enclosed by the steeply westdipping, west-facing sediments of the Cobar Group, and comprise lenticular steeply north-pitching and eastdipping zones of sulphide mineralization which range in composition from massive pyrite-sphalerite-pyrrhotitegalena to less massive pyrite-pyrrhotite-chalcopyrite varieties.The thinly bedded siltstones, shales, and greywackes enclosing the mineralization appear to have derived some of their constituents from volcanic sources. They have been metamorphosed to the greenschist facies of regional metamorphism. At least two stages of deformation and folding have occurred. The first stage folded the rocks on a south pitching fold axis into their present configuration, and superimposed a strong axial plane cleavage which subsequently guided the emplacement of the mineralization. The second stage of deformation is considered to have controlled the zonal distribution of the orebodies.

Jan 1, 1970

The Kwademen Au deposit was discovered in 1977- 1978 following a regional geochemical survey carried out as part of a UNDP (United Nations Development Programme) and BUMIGEB (Bureau des Mines et de la Geologie du Burkina) mineral exploration programme. The climate in Burkina Faso is rather dry, with markedly seasonal rainfall averaging 800 mm pa in the Kwademen project area. The relief is low and the drainage poorly developed, so that soil sampling was preferred to stream sediment sampling. Rocks have been subjected to deep lateritic weathering, so that they are transformed into a mixture of Fe-oxides and kaolinite over depths varying between 30 and 40 m. At the regional stage, soil samples (30-40 cm depth) were collected a a 300 x 500 m grid. The Kwademen deposit was indicated by Cu, Zn, Mo and Au anomalies. Subsequently, an area of 9.2 km2 was covered by a detailed geochemical survey by soil (100 x 50 m) and auger sampling. The regional anomaly was fully confirmed, and subsequent drilling intersected mineralized ore shoots, justifying the establishment of an evaluation project led by the U.N.R.F. (United Nations Revolving Fund) in 1983- 1985.

Jan 1, 1988

Discovered in 1896, the Sons of Gwalia orebody is located in a ductile mylonite zone within a sequence of Archaean pillow metabasalts and minor metasediments of greenschist facies which are variably sheared.The ore zone has good continuity, being 110 m wide and 500 m long, dipping 45 degrees east and plunging 70 degrees to the south to a depth of 1500 m downplunge. A strongly-developed foliation is present together with a prominent lineation paralleling the plunge. The mylonite zone consists of unmineralised chlorite schist and a 'U' shaped mineralised zone of chlorite-sericite schist with varying amounts of quartz-carbonate as veins parallel to foliation, boudins, and locally as massive quartz-carbonate. Pyrite is the dominant sulphide present.Grade control utilises RC holes on a 10 m x 10 m pattern, with infill blast rig holes 5 m deep where necessary.Some visual control of ore boundaries is present and, combined with good ore continuity and a knowledge of the structure of the orebody, enables cost-effective grade control to be achieved. To-date, over three million ounces of gold have been produced from the orebody.

Jan 1, 1993

The U.S. Bureau of Mines has developed a prototype cross well acoustic logging system and complementary tomogr`aphic image reconstruction software for the detection and delineation of abandoned underground mines and associated subsidence failure in relatively shallow environments. The logging system uses a piezoelectric, cylindrical bender as an acoustic source. A triaxial accelerometer assembly, designed to be rigidly locked in the borehole, is the receiver portion of the logging system. Both the source and receiver probes operate at high frequencies, thus providing short wavelengths capable of resolving small features in most rock types. A modified van with a dual-drum wireline winch, 4-channel data acquisition system, power amplifiers, and waveform generator supports field operation of the logging system. A field study was conducted at a test site in San Antonio, Texas, to demonstrate the cross well acoustic logging system. The underlying rock at the test site is similar to stratified sediments in coal measures. First- arrival travel times were interpreted by tomographic reconstruction of the velocity field in the two-dimensional cross section between the source and receiver boreholes. The resulting image correlates well with geological borehole logging data for the test site.

Jan 1, 1992

The Circum-Pacific area is one of the most important gigantic skarn-metallogenic belts in the world. In more than 20 coastwise countries of this region, there exist thousands skarn deposits of different types. According to the differences of major metallic elements, the skarn deposits may be classified into seven subtypes, i.e. Fe, Cu, Pb-Zn, W, Sn, Mo and Au skarn deposits. In this paper, the distribution. and geological characteristics of above-mentioned types of skarn deposits are described briefly. Skarn deposits may also be classified on the basis of the dominant calc(magnesian)-silicate mineral assemblages into four types: magnesian, calcic, manganoan, and alkaline skarn types. Magnesian skarns may be associated with Fe, Cu, Au,, Sn, B, Be mineralization, calcic skarns with Fe, Cu, W, Mo, An, Be, Pb, Zn, Sn minerailization, while the alkaline skarns occur in U(Th, Nb) deposits. The skarn deposits of both East and West Pacific rims have many general characters, but have some diferences in geotectonic settings, intensities of mineralization, distribution, and metallogenic epoches. In this paper, the minerogenetic series and the mineralizing specialities of related magmatic rocks of the skarn deposits are also discussed.

Jan 1, 1990

By Horrocks KRS, Smitham JB, Ellison JF

This paper describes the development and installation of equipment for continuously measuring separating density in the dense medium cyclone circuits of the four million tpa Port Kembla B/C plant coal washeries. Monitoring equipment consisting of magnetic coils and differential pressure cells were installed in U-tubes taking the full flow of magnetite from the drain sections of the product drain and rinse screens. The monitoring equipment measures overflow magnetics concentration and overflow density continuously and has operated since 1989. From these measurements and calibration trials, the separating density of operating cyclone modules can be inferred reliably. Variographic analyses of the data show that medium density control to +/- 0.002 RD units and separation density control to +/- 0.007 RD units are achievable. Either method for measuring separation density can be used with approximately the same accuracy, although the overflow density measurement technique suffers from the need to have regular flushing of the Dp cells which complicates the signal analysis. Data from the plant shows that separation density can be controlled by regulating medium density, but the assumption of a constant offset between medium density and separation density is erroneous.

Jan 1, 1993

The late Carboniferous to early Permian Featherbed Volcanics cover an area of about 3000km near the western margin of the Hodgkinson Basin, in northeastern Queensland. The dominantly ignimbritic volcanic rocks are mostly confined to a single, composite, volcano-tectonic depression, but, along with the associated intrusive rocks, may be divided into two main groups: late Carboniferous I- type rocks and early Permian A-type rocks. Late Carboniferous I-type andesitic to rhyolitic ignimbrites and minor andesite lava crop out in the southeastern, southern, and southwestern parts of the complex, mostly confined to a basin-like depression, or "sag" structure, and are associated with coeval dioritic (and rare gabbroic) to granitic intrusive rocks. Extensive Sn, W and base- metal, and some Au, mineralisation are associated with these rocks, particularly in the southeast. The main part of the complex is of early Permian age, and consists almost entirely of A-type rhyolitic ignimbrite and relatively minor volumes of lava intruded by a peripheral ring dyke of porphyritic microgranite and by resurgent-type plutons of porphyritic microgranite and microgranodiorite. These rocks are associated with sparse base-metal, Au, U, W, and Sn mineralisation.

Jan 1, 1987

An improved method of sample recovery for use with rotary percussion drilling has been developed. Cuttings can be recovered continuously from either dry or wet drilling, and the recovery under dry conditions is seldom below 99% of the cuttings brought to the surface by the rig. The system is designed for use with top drive drilling rigs using flush-jointed drill rods. The key feature of the system is a self-aligning mechanical seal around the drill rods. The sealing unit is removably fixed to a collar section of cas ing. the cuttings are recovered in a plastic bag attached to the bottom outlet of a cyclone. A valve at the bottom of the cyclone permits the cuttings representing various depths to I,e recovered separately for examination eind 0(iclysis. [u the Iron Monarch quarry, two percussion holes were drilled to depths if 30 metres and 28 metres using the unproved sample recovery system, and diamond drill holes bored 1 metre from each percussion hole. Samples from each hole were sectionalized over metre intervals and analysed for iron, silica, alumina and loss on

Jan 1, 1976

By George G

The Circum-Pacific Map Project is a cooperative international effort to prepare and publish geological, geophysical and mineral resource maps of the Pacific Basin and adjacent land areas. Earth scientists representing 180 organizations from more than 40 Pacific Rim countries are participating in the work. The project is directed by a committee established 14 years ago as an activity of the non-profit Circuin-Pacific Council for Energy and Mineral Resources. Technical and cartographic support is provided by the U.S. Geological Survey. The Circum-Pacific Map Project is organized under five regional panels of experts on the geology and resources of the four quadrants of the Pacific and Antarctica. A series of five 1:10,000,000-scale regional maps and a 1:17,000,000-scale map of the entire Project area, the Pacific Basin Sheet, provide the cartographic base. Forty-eight individual sheets are planned and thirty have been published in eight different series, including base maps, geography, plate tectonics, geology, energy resources, mineral resources, tectonics and geodynamics. Additional special single-sheet thematic maps on the Pacific Basin base have been published and are planned for a total of more than 50 individual sheets.

Jan 1, 1987

Uranium minerals were found in Australia as early as 1869, but it was not until the 1940's that a search specifically for uranium was begun. Instrument types and techniques used in early exploration are still used today, but have been developed into more sophisticated and portable types. Recent improvements in exploration have been the introduction of the gamma ray spectrometer, radon sampling and geochemical surveys. The environments of presently defined uranium deposits are predominantly sedimentary. Known deposits in igneous environments are usually small. The size of targets which are likely to provide economic deposits is of the order of 10,000 tons U308, producible at a cost of less than $10 per pound. Such targets are most likely to be in Precambrian sediments or in granitic masses. Recent exploration in Australia has included investigation of Precambrian sediments, Precambrian and Palaeozoic granites, Mesozoic and Tertiary sediments, Precambrian volcanic rocks and brecciated masses of unknown age. The origin and method of emplacement of uranium in these environments is not well known but there are indications that syngenetic sedimentary processes are important, and volcanic rocks may make a major contribution to the supply of uranium.

Jan 1, 1970

Ranger Uranium Mines Pty. Ltd. operates an open pit mine and ore treatment plant in the Northern Territory designed to produce 3 000 tonne/yr of U308 in yellowcake from 3 500 tonne/day of mill feed. The construction of this project was completed in 1981, 12 years after the discovery of the orebody. Wright-Davy, a Joint Venture of Wright Engineers and Davy McKee Pacific, were the Project Managers and Designers of the $270 million ore treatment plant and associated infrastructure. The project was designed in Sydney in -an office integrated with the Client, staffed by 35 key personnel drawn from Wright Engineers and Davy McKee, supplemented by personnel hired for the project. The peak Wright-Davy workforce in Sydney of 200 contained 113 design staff. The design principle of using the best practicable proven technology resulted in a plant which easily produces its design output using ore types outside the design criteria. The structuring of the project systems and industrial relations policies contributed to construction being completed within time and under budget. The plant was built without any major industrial dispute occurring and no dispute arose due to the uranium issue.

Jan 1, 1983

The T33-34 blast, the first major blast at Mount Isa Mines, broke 1,360,000 tonnes of copper ore using 349 tonnes of explosives. The original concept of firing T33, T34, T35 and U37 separately was changed during the life of the project due to adverse ground conditions. These conditions also caused the stoping method to be modified after the firing of the stopes had started. To stabilise the two stopes T33 and T34 where large fall off was occurring, rib pillars were left in the original slot. This caused the blast design to be more complex as these rib pillars had to "lead" the blast. The implication of such a large blast on the underground and surface environment was thoroughly investigated and precautions taken. The charging time of the blast was six weeks. Hook-up was started four days before the blast and continued until two hours prior to the blast. Detailed scheduling was carried out of other work that had to be done in the 24 hours before the blast to ensure that there were no delays in the firing.

Jan 1, 1977

By Y Li

An ilmenite ore from the Murray Basin was initially characterised using combined X-ray Fluorescence Spectroscopy (XRF), X-Ray Diffraction (XRD), Scanning Electron Microscope (SEM) and Electron Probe Microanalysis (EPMA) techniques. XRF analysis showed the ilmenite sample contained 58.7 wt per cent TiO2 and 26.2 wt per cent Fe2O3. Major impurities included: Cr2O3 (4.5 wt per cent), Al2O3 (2.7 wt per cent), SiO2 (1.9 wt per cent), Mn3O4 (1.5 wt per cent) and MgO (1.1 wt per cent). Manganese and magnesium were present as solid solution components within the ilmenite lattice while the elevated Al2O3 and SiO2 levels were due to separate aluminosilicate gangue minerals. Chromium was associated with discrete chrome spinel gangue phases of variable composition, (Fe,Mg)(Cr,Al)2O4. Quantitative XRD analysis of the sample identified rutile (12 per cent), ilmenite (11 per cent), and pseudorutile (67 per cent) as the main titanium-containing phases and chrome-rich spinels (seven per cent) as the major impurity phase. Minor quartz, aluminosilicates, zircon and monazite were also present. The ilmenite was mixed with synthetic graphite, pressed into pellets and reduced carbothermally in nitrogen at 1200 and 1400°C with C/O molar ratio of 1.2. Titanium oxide in the ilmenite was converted to titanium oxycarbonitride. Iron oxides were reduced to metallic iron. The Changes of impurities as a result of reduction was examined by SEM and EPMA analyses. Iron and chromium oxides within Fe-rich chromite were reduced to form a Fe-Cr-C alloy. Mg-rich chrome spinels were partly reduced at 1200°C. Zircon particles were not reduced at 1200°C, but were significantly reduced at 1400°C, with the particles becoming porous and the silicon being removed.

Oct 5, 2011