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By Y Cao, J C. Tien

Occupational health and safety is essential in modern mining workplaces and in China it is often not given enough emphasis due to a lack of knowledge and/or appreciation. Although many health and safety regulations have been passed over the years, serious and relevant laws and regulations on mine health and safety are of recent history (since 2002), the level of stringent enforcement is still inconsistent and accurate field data are scant and not readily available. As of year-end 2006 there were 676 562 recorded cases of occupational diseases in China, of which 616 442 or 91 per cent were miners’ pneumoconiosis. Of these, 146 195 (23 per cent) have died, and an average of 10 000 new cases were added every year between 1991 and 2006. Another report shows that 93.18 per cent of miners have never had a contract with their companies, which means their cases were not even part of China’s official statistics. This study attempts to examine the prevalence of occupational diseases in the Chinese mining industry during 2000–2013, compiled from government annual reports and academic studies. The research will review the correlational analysis among occupational diseases, ventilation practices, protection devices and legislation.CITATION:Cao, Y and Tien, J C, 2015. Occupational diseases in China, with the emphasis on its occurrence in Chinese mine workers, in Proceedings The Australian Mine Ventilation Conference, pp 155–160 (The Australasian Institute of Mining and Metallurgy: Melbourne).

Aug 31, 2015

The Physical Basis of Non-Random Breakage in an Iron-Oxide Ore Hosted Copper Gold Ore

Sep 13, 2010

Norway, a country large in area but small in population, has put large effort in protect- ion of its inhabitants in case of war. The Civil Defence has provided shelters for more than 50% of the population. Some of these shelters are put into rock. Since rock installations give large resis- tance against weapon effects and also by advan- tage can be used for several purposes in peace- time, an interesting development has taken place the last decades. In towns and cities you will find sport halls, swimming pools, bowling and shooting ranges etc in rock, which easely can be conver- ted to civil defence shelters. Some typical installations are highlighted in the following.

Jan 1, 1987

By J A. Shonhardt, I Porter

All types of coal are liable to spontaneous combustion to a variable degree according to the inherent characteristics of the coal and also extrinsic factors. In order to successfully extract coal from highly capital-intensive longwall mining operations it is necessary to evaluate and manage any risks that may be present due to spontaneous combustion. A spontaneous combustion risk management plan for longwall mining is described in this paper. This risk management system comprises identification of conditions promoting spontaneous combustion risk, a laboratory or empirical risk classification system, determination of gas ladder, adoption of adequate ventilation plans and gas monitoring systems that will lead to the development of the spontaneous combustion action plan. The risk management system was applied to a greenfield site in NSW in 1992 when prediction of a high-risk category for the coal seam was made. After commencement of production a spontaneous heating problem emerged as predicted. Description of the case history of spontaneous combustion risk management for a longwall operation in this coal seam is included in this paper.

Jan 1, 2003

By Rowe J

The case study is based on the largest ore deposit at Mt. Lyell; the Prince Lyell deposit, comprising a regular lensoid mass of dissemina- ted and vein pyrite-chalcopyrite mineralisation. Reserve estimation employs conventional techniques, based on diamond drill hole and relevant development sampling data. Probable ore reserves are estimated using the contouring (isoline) method an longitudinal projections for ore thickness and accumulation (m %Cu) at a '0.8% Cu' cutoff. Final stope and pillar res- erve estimates (proved ore) are derived from designed ring tonnages and contoured accumula- tion for individual mining units, following more intensive sampling. Systematic grade control procedures have been adopted and individual stopes and pillars reconciled against mill production. The proved ore estimates have been found to com- pare favourably with the reconciled production.

Jan 1, 1979

Correlation of Air Recovery with Thin Film and Froth Stability in Flotation

Sep 13, 2010

By V N. Rudashevsky, F Melcher, J Lodziak, D Klosa, N S. Rudashevsky, M Sitnikova, L Gast

A combination of novel and æclassicÆ methods, namely electric pulse disaggregation (EPD), hydroseparation (HS), preparation of monolayer polished sections, and mineral liberation analysis (MLA) was employed to study ores from platinum pipes (Bushveld Complex, South Africa), pristine PGE mineralisation of the Main Sulfide Zone (Great Dyke, Zimbabwe), as well as ancient and modern gold/PGM placer deposits. It is shown here that the EPD technique liberates mineral grains of interest without any visible destruction allowing the study and analysis of individual rock-forming and ore minerals, in our case especially platinum-group minerals. The HS method is an effective tool in concentrating heavy minerals by factors up to 10 000 fold. As near-total recovery of grains >10 ¦m is achieved, the nugget effect can be overcome also in case of limited availability of samples (drill core, museum specimens). The MLA technique is a fast tool to detect and characterise mineral phases in ores and ore processing products. Many mineralogical parameters of individual grains and mineral assemblages can be deducted and documented. The results show that the techniques employed, either on their own or in combination, provide a wide range of additional information especially on platinum ores which is beneficial to both the researcher and the metallurgist.

Jan 1, 2008

By P Holtham, K Duffy, L Pyle, W Valery

The mining industry is becoming increasingly focused on pre-concentration due to its potential economic and environmental benefits, particularly for the more complex, low-grade, high throughput operations now being developed. Advances in technology have seen bulk ore sorting (BOS) trialled at several operations. However, BOS should not be seen as a ‘silver bullet’, it can offer significant benefits, but only under the right conditions. Deposits with interspersed mineralogy or disseminated, fine-grained minerals can be difficult for BOS. Large batches of barren or low-grade material are required for BOS to be effective. Hatch has recently completed several studies for clients who believed that bulk sorting was the most suitable pre-concentration technique for their operation, based only on an assumed sorter recovery or on laboratory trials of the chosen sensor. However, minimal consideration had been given to the heterogeneity of the deposit, the achievable separation batch size or sensor repeatability. Evaluation of BOS needs to consider both heterogeneity and sensor suitability. The valuable or gangue mineral must be present in such a way that it can be separated effectively in the large bulk sorting batch sizes, without competing minerals or changing ore characteristics affecting the metal upgrade or recovery. Also, the sensor chosen must be able to detect either the valuable mineral, a proxy for the valuable mineral, or a gangue mineral for rejection with sufficient accuracy and precision (repeatability). This paper presents three recent case studies, emphasizing markers which indicated that bulk sorting was unsuitable for the project whilst highlighting the pre-concentration technologies which were applicable (including particle sorting, and coarse particle gravity separation). The modelling methodology, equipment sizing and forward work plans developed to verify these alternative solutions are also presented, demonstrating the key factors contributing to a thorough scoping assessment.

Aug 24, 2022

By A F. Cooper

Otago Schist in the Mount Patriarch, High Burn and Cameron Creek areas of northwest Otago grades from textural grade IIA in the east to textural grade III in the west. The entire region is of the actinolite-pumpellyite metamorphic facies. Lithologies in the area are interbedded turbidite sequences comprising pelite and psammite together with pebble conglomerate, greenschist and metachert horizons. The mineral assemblage of the schist is typically quartz-albite-epidote-actinolite-pumpellyite-chlorite-stilpnomelane-calcite. A good foliation is well defined in the area and is predominantly parallel to bedding, except in hinges of mesoscopic isoclinal folds. The structure of the area appears to be defined by a large southwest plunging isoclinal fold defined by bedding with a steeply dipping axial planar foliation. Kink folding and dextral strike-slip faulting in the area postdates the ductile phase of deformation. Pods of rhodonite, rhodochrosite, spessartine garnet, coombsite, caryopilite, Mnstilpnomelane and Ni-Cu-Zn sulphides were found in concordant metachert layers in the Mount Patriarch area. Metachert was also found in float in the Cameron Creek area. Malachite occurrences relating to copper mineralisation were also noted in a green metachert horizon on the eastern flank of Mount Patriarch. The coombsite, in only the third observation worldwide, is the most Fe-rich variety reported.

Jan 1, 2003

By D R. Peacor, J L. Mauk

Dioctahedral clay minerals in the volcanic-hosted Golden Cross epithermal Au deposit, New Zealand, have been investigated by petrography, X-ray diffraction (XRD), scanning electron microscopy (SEM) and transmission electron microscopy/analytical electron microscopy (TEM/AEM) to determine the nature of these minerals in a hydrothermal ore deposit. Heterogeneity in the distribution of dioctahedral clays is observed from the hand-specimen scale to the TEM scale, indicating that primary rock textures and fluid pathways (related to rock type, porosity/permeability and fluid/rock ratios), in addition to temperature, are important factors controlling the distribution. As the proportion of illite in mixed-layer illite/smectite (I/S) decreases, TEM observations show decreasing layer stacking order, parallelism of packets, and packet size, and increasing apparent porosity. AEM structural data show a corresponding decrease in AlIV, AlVI, and K+, and an increase in Si, Ca2+, and Fetotal. The observations of this study indicate that local dioctahedral clay mineral reaction progress is controlled mainly by permeability and structure, but that this is superimposed on a predictable, system-wide clay mineral distribution that is controlled by temperature and fluid/rock ratio.

Jan 1, 1999

By T Harrington, M Cox

There have been many changes in the Australian mining industry during the last 30 years. One of the most dramatic changes, from a geological perspective, is the reduction of in-house geological staffing and an ever increasing reliance on contract and consulting services. As a result, there has been a change in the way geological information is generated, managed and retained within the industry. This paper describes the changes that have taken place in the industry, provides two case studies of how companies manage their geological Intellectual Property and reviews some of the issues associated with management of in-house and outsourced geology services.

Jan 1, 2009

Staff turnover percentages on projects in the minerals sector are at levels that would not be accepted in business less than five years ago. While this is being driven in part by the shortage in skills to service the industry there are underlying factors, beyond the increases in remuneration, adding to the turnover. Having identified the five major reasons why people do not stay, this paper confirms that leaders and the various styles are common to all companies. The paper comments briefly on these major reasons and suggests the problem is firmly with management. It also offers possible remedies to reduce the attrition and therefore improve the opportunities for a quality project evaluation.

Jan 1, 2009

Mineral exploration conducted over a wide area of the State during the period 1960 to 1973 has resulted in the discovery of a number of significant deposits. Base metals, particularly copper, have been of prime interest while, more recently, the search for uranium and coal have assumed import- ance. Expenditure of $27.6 million by companies during the period under re- view has located 580,000 tonnes of cop- per, 370,000 tonnes of zinc, 350,000 tonnes of lead, 24 million Kg of uran- ium oxide and 2,500 million tonnes of coal. A variety of other metals and non metallic and industrial minerals have been investigated in a diversity of geological environments.

Jan 1, 1975

Underground mine planning is characterised by a series of designs, starting with prefeasibility and culminating in operational. Information on the mineralisation and geotechnical conditions is available in increasing levels of detail, as development occurs. In the recently completed AMIRA Planning and Rapid Integrated Mine Optimisation (PRIMO) project, a methodology for producing good strategic and then tactical designs using new optimisation tools, was developed. At the strategic level, fundamental decisions must be made such as those relating to cut-off grade, bench heights, mining methods, access and haulage systems, properties of the mill, etc. The inputs are the block and financial models, geotechnical data, infrastructure and production costs, etc. Stope definition for strategic designs includes bench RLs (relative levels), orebody envelopes, and design and placement of amalgamated or simplified stopes. If multiple mining methods are under consideration, then stopes need to be associated with these. Access design must take into account decisions such as declines versus shafts, a template for level layouts and the topology of the access network. Some of the geotechnical and physical constraints are relaxed for strategic design stages. Strategic scheduling is high level, from a month to a year at a time. In the PRIMO project, software tools have been developed enabling the mine planner to rapidly produce a large number of such strategic designs. After the designs have been evaluated, the highest value designs are chosen and a small number of these can then be further refined at a tactical level. For these designs, the first step is determination of all stopes meeting physical and geotechnical requirements and constraints, allowing for complex stope shapes. Next, detailed layout of the mine access network is obtained, satisfying all operational and geotechnical constraints. Finally, more detailed scheduling is performed, over shorter time periods. The Melbourne University group has focused on optimal access design. In particular, the access network is optimised for minimum cost, taking into account the cost of haulage and development over the lifetime of the mine. Costs vary over the different parts of the network depending on the quantity of haulage and so a weighted network optimisation problem has to be solved. We have developed two software tools for this task, decline optimisation tool (DOT) and planar underground network optimiser (PUNO). DOT produces an optimal network of declines and crosscuts connecting access points on the levels to a portal or break-out point from existing infrastructure. PUNO designs the level layout, including footwall and hanging wall drives, development drives and connections to vent raises. A survey will be given of the capabilities of DOT and PUNO when used on some recent case studies. Our current goals include incorporating some aspects of ventilation design and modelling the development costs when additional ground support is required. This is an abstract only. A full paper was not prepared for this abstract.

Dec 6, 2010

In North-West Nelson the Riwaka Complex, a linear basic intrusive complex, is exposed for approximately 45 km. Some 500 km south, across the Alpine Fault, a linear zone of similar but less well known basic intrusives that may be correlatives of the Riwaka Complex is exposed discontinuously for about 80 km. The Complex was emplaced at several centres along a major tensional fracture zone that developed in upper Carboniferous to Lower Permian time. This fracture zone probably formed in response to the development of a west dipping subduction zone that gave rise to the Permian volcanic arcs in east Nelson and western Southland. The Riwaka Complex contains three rock suites. The Fractionation Suite, characterized by cyclic mineral layering and small scale cumulus banding is the largest and is divided into the Ultramafic, Hornblende and Plagioclase Series, each of which is subdivided into several units. The Cumulus Gabbros represent a restricted but important suite of unusual composition, while the third suite is the late phase Diorite Suite. Except in the lower units of the Ultramafic Series sulfide mineralisation is widespread. Pyrrhotite is the dominant sulfide with lesser chalcopyrite pentlandite and pyrite. Four significant zones of sulfide accumulation are recognised and discussed in some detail. Evidence suggests that the primary magma from which the Riwaka Complex was derived was sulfur deficient. It is concluded that the sulfur content of the Riwaka Complex was derived from assimilation of sulfur rich wall rocks during intrusive processes.

Jan 1, 1980

By Fookes R. A, Bunch K, Gravitis V. L, Watt J. S

The combustible volatile matter in coal mine roadway dusts (CVM) has been determined using x-ray backscatter techniques. The correlation between x-ray and chemical techniques is reasonably good for the 92 samples from collieries on the Bulli seam, and the maximum error expected at the maximum level of 11· 5 weight per cent CVM permitted in the N.S.W. Coal Mines Regulation Act, 1912, as amended, is about ± 2·5 weight per cent. This x-ray technique can be used only when the combustible volatile content of the coal matter (cvm) varies within a limited range, and a separate calibration is required for each coal seam.Portable equipment based on a radioisotope x-ray source ahd digital ratemeter makes possible simple and rapid analysis, and with adaptation to use in coal mines should lead to much more comprehensive testing- ofroadways and hence improved overall prevention of coal dust explosions.

Jan 1, 1977

By S D. C Rabone

An elongate belt containing granodiorite stocks with associated stockwork molybdenum mineralisation in west Nelson is correlated with the I-type Separation Point Suite of mid Cretaceous age. Trace element characteristics of the 'Mo-granites', and the Separation Point Batholith strongly suggest a primitive, subcrustal origin for these granitoids, by partial melting of oceanic basaltic crust or upper mantle material in a subduction zone. They were emplaced in the upper crust without undergoing significant differentiation or contamination by sialic crust. Molybdenum, which is at levels of approximately 5 ppm in unaltered granite, is not significantly reduced in altered (but unmineralised) granite. This suggests the metallisation has a magmatic, subcrustal source and is not derived by hydrothermal leaching of upper crustal rocks or the granitic host rocks. Geochemistry of the 'Mo-granite' belt, in particular low K2O, calc-alkali to calcic Peacock Index, high Sr and TiO2, and low Rb, Nb and F, suggest classification as calcic granitoids similar to those which host porphyry copper deposits, indicating grades of mineralisation are likely to be low.

Jan 1, 1987

By T Raynlyn, R J. Holmes, J R. Manuel, A Poliakov, L Lu

The prediction of sintering performance of iron ore fines and the possibility of targeted optimisation of specific sinter properties are very important for both the iron ore industry and related research organisations. Physical pilot-scale sinter runs require large amounts of raw materials and are expensive, so it is critical to target large test work programs with many different sintering parameters effectively. To predict values for sintering performance parameters such as tumble index (TI), low temperature reduction disintegration index (RDI) and productivity, a comprehensive database of pilot-scale sintering experimental results has been established and empirical modeling conducted. Similarly to earlier work, physical, chemical and mineralogical characteristics of the iron ores have been considered. However, in contrast to the previous work where only one textural parameter was taken into account, namely the proportion of dense haematite ore texture, the current model includes the abundances of several different textures which were combined into different textural factors corresponding to different sinter properties. Coefficients for the variables within specific regression equations can provide a better understanding of the effect of the variables on the corresponding sintering performance. The modelling results have also been used for predicting the sintering performance of mixtures that were not part of the database used for establishing the models. Comparison of experimental and modeling results for the verification test data is also reported in this paper.

Jan 1, 2009

Most people are familiar with Euclidean dimensions: zero for a point; one for a line; two for a plane; and three for a volume. Howeverbobjects are not actually Euclidean, but lie somewhere between Euclidean æend-membersÆ with a non-integer fractal (or æfractionalÆ) dimension. The fractal dimension D is a measure of the relative importance of large versus small. Consider the trace of a coastline on a map. It has a fractal dimension (1 =D =2) somewhere between a line (dimension = 1) and a plane (dimension = 2). The more tortuous the coastline, the higher the fractal dimension, and the closer it becomes towards a plane. The concepts of fractals and spatial geometry can be applied to a wide range of geologicaVmining problems as well as than those dealing with space. One commonly quoted fractal relation is the log-log relationship of ore-grade and tonnage. Until recently, we have never been able to define or measure spatial-geometry, but new developments in mathematics have provided a means by which to quantity and apply it to our problems.

Jan 1, 1992

By S F. Simmons

At Broadlands-Ohaaki geothermal system, TVZ, mineral distribution patterns in geothermal wells are analogous to those in epithermal veins. Fluid flow through geothermal wells is focused over vertical intervals >500 m with discharge at rates up to 90 l/s. Focused flow at similar rates also occurs in natural systems where hydrothermal eruption vents provide enhanced vertical permeability. These vents are commonly aligned with the tectonic fabric, indicating fault control at depth. We suggest that host rock strength and structural context exert significant control on the hydrological regime conducive to epithermal mineralisation.

Jan 1, 2005