Search Documents

By R G. Barker

The NZ Minerals Industry Association has continued to advance the interests of the minerals sector through leading the establishment of a Minerals Industry Advisory Committee, and the preparation of a technology strategy with funding assistance from the Foundation for Research, Science and Technology. The current moves mirror those of more than 30 years ago when a government initiative led to a resurgence of exploration through amending the mining legislation, redirecting Government research priorities and tax changes. The economic and political and commercial environment in 2001 is very different from that of the 1960s and success of these new initiatives depends on the continuing support and involvement of all sectors of the minerals industry, and building an improved relationship with the Government and the public.

Jan 1, 2001

Five types of mineral resource were known in the sedimentary cover of the oceans and seas floors prior to the 1980s: 1. hydrocarbon fields including some very large zones of oil and gas accumulation; 2. æRed SeaÆ type thermal oozes with increased concentrations of noble metals; 3. ferromanganese nodules; 4. concentrations of metallic sulphides (æBlack SmokersÆ); and 5. cobalt-bearing ferromanganese crusts on the summits and slopes of seamounts.   Since then, the so called æWhite SmokersÆ, containing sulphides of copper and zinc, have been discovered. The ore horizons (manganese, copper, nickel and other metals) of the sedimentary cover of deep-sea basins comprise a sixth type of mineral resource in the oceans. These horizons have not only a theoretical, but also a principal economic significance.

Jan 1, 1995

By P Clark, P A. Kirsch, R Tapia Rivera

Community members’ sources of information about companies’ social investments are often influenced by the messages in a variety of communication channels, such as newspapers, television and social media. In this sea of communication channels, corporate communications may not always have the desired effect in influencing community perceptions. This paper explores the efficacy of communication between mining companies and communities in Chile through content analysis of corporate sustainability reports and newspaper reporting.Chilean media reporting between 2005 and 2013 is examined to identify community perceptions of corporate social investments made by mining companies. Content within the Chilean newspapers El Mercurio (national) and Soy Chile (regional) is contrasted with content from corporate sustainability reports published by The National Copper Corporation of Chile (Codelco) and Barrick Gold Corporation, Canada (Barrick) for the same period. The objective is to identify differences in the way that corporate social investments are reported by companies in sustainable development reporting and by media in newspapers.Overall, the study demonstrates that the media’s framing and reporting of corporate activities was more negative than positive. Moreover, media outlets tended to focus upon the ‘negative impacts’ or ‘damage’ to communities brought about by mining developments. Conversely, companies’ public communications were largely focused upon direct improvements in livelihoods (health, education, etc) of neighbouring communities. This preliminary study provides a baseline for the development of new formats of effective communication with neighbouring communities. The paper advocates for an increase in participatory mechanisms with affected parties, which could lead towards a greater mutual understanding of the impacts and draw parties closer together.CITATION:Tapia Rivera, R, Kirsch, P A and Clark, P, 2014. Challenging Perceptions? Sustainability Reporting, the Media and Mining, in Proceedings Life-of-Mine 2014 , pp 413–426 (The Australasian Institute of Mining and Metallurgy: Melbourne).

Jul 16, 2014

The Ministry of Economic Development has as its slogan æTogether making the differenceÆ. The Ministry is required to work in partnership with the private sector, local authorities, Maori economic entities, trade unions and community groups to transform New Zealand's industrial and economic base. The Government is seeking to achieve sustainable and balanced economic development by: being more actively involved in economic management; working in partnership with the public and private sector and with worker and business interests; focusing on adding value in industries (including primary industries) with long term potential; and bringing the tools of economic policy together in a coordinated way. The Ministry, particularly through its operating group Crown Minerals, is committed to working with industry to achieve mutual goals and to obtain continuing investment in minerals and coal exploration and mining and an active New Zealand minerals industry.

Jan 1, 2000

Development and Validation of Ore Characterisation Test and its Use in Variability Campaigns of Comminution Circuits Impact testing was developed by assessing the fragmentation characteristics of ore samples after controlled impact. Standard methods are, however, limited to relatively large and coarse samples, which thus precludes their use in early stages of projects, as well as where only drill cores are available. The method described in this paper is based on the same concepts of controlled ore breakage, but using relatively smaller samples. It is particularly useful in assessing the variability of ore characteristics in early stages of greenfield projects, as well as in predicting the performance of existing grinding circuits. A validation program was carried out in which a good adherence to the original test results was obtained. The results were used for (a) simulation of a copper comminution circuit as a function of the ore characteristics, and (b) evaluation of sampling protocols used for assessing fragmentation characteristics.

Sep 13, 2010

By P J. Minehan

The investigation of the potential of the Webb/Baynes block of the Buller coalfield for anode carbon manufacture has generated much information on the physical beneficiation characteristics of the Buller coals in general. A further 36 drill holes of the block in question and several other samples have been analysed by sink/float analysis, either at a single density or over a range of densities. In addition, many samples have been beneficiated on a laboratory shaking table or by flotation. The ash content can be reduced by a variable factor. The reduction factor of between two and four by sink/float analysts is understandably less for tabling where separation is not perfect. All Buller coals behave similarly, there being greater ash reduction factors for higher ash coals.

Jan 1, 1983

Permitting, engineering and evaluation, detailed design and construction aspects of the Golden Cross goldmining project in New Zealand are briefly reviewed. The extremely lengthy and complicated governmental approval process together with the delaying tactics of opponents of the project are outlined and comment is made on aspects of the draft legislation proposed as part of the overhaul of New Zealand's resource management laws.

Jan 1, 1990

Kinetic Study on the Leaching of Vanadium from LD Converter Slag Using Sulfuric Acid In order to reduce the environmental impact due to land disposal of LD (Linz-Donawitz) converter slag from steelmaking plant and to valorise this waste material, an acid leaching study was carried out to assess the effect of several parameters on the kinetics of vanadium dissolution. The characterisation and morphology of the feed investigated using XRD, XRF. The factors influencing leaching vanadium such as particle size, temperature, slurry density and the concentration of sulfuric acid were investigated and optimised. The maximum vanadium recovery about 95 per cent achieved at 70¦C, S/L: 1/15, acid concentration: 3M and for 150 minutes of leaching time. The dissolution of vanadium in sulfuric acid shows that there are two stages in the kinetics of leaching. At the first 15 minutes, there is a sharp increase in the amount of vanadium extracted and at longer leaching time, the extraction increase slightly. In the present work, the shrinking core model (SCM) was used to describe the acid leaching of vanadium compounds. A summary of the controlling regimes in the SCM are examined below for short time (less than 12 min.) and long time (more than 30 min.) stages. So, it was found that the kinetics of leaching in both stages is controlled by solid product diffusion regime.

Sep 13, 2010

By A M. Sherwood

The Otago and Southland lignite deposits represent by far the largest known fossil energy resources in New Zealand. Despite their size they have remained virtually untouched since exploration in the 1970s and 1980s defined their extent. In total there is an estimated 10.9 billion tonnes of lignite in 13 defined fields in Otago and Southland. Much of the exploration work only targeted seams at shallow depth and it is highly probable that there are further resources at depth in the fields that have been explored to date.   L&M Lignite Limited (L&M) holds exploration permits over a number of lignite deposits and is currently engaged in pre-feasibility studies to investigate the potential of the lignites for gasification. L&M is focussing its studies on the Hawkdun and Ashers-Waituna deposits. Coal quality in these deposits, particularly Ashers-Waituna, is highly suitable for gasification. In total the two deposits contain 1647 Mt of potentially recoverable lignite. L&M has engaged a variety of consultants to progress this project. The Hawkdun and Ashers-Waituna deposit databases have been re-evaluated and the resources remodelled. Further drilling has been carried out and the coal quality database has been expanded. The baseline project is to develop a mine to feed a plant that will produce liquids, specifically low-sulphur diesel and naptha, using the Fischer-Tropsch process. The project anticipates a staged development of 10 000 barrel per day units, each requiring mining at the rate of 12 700 tonnes of lignite per day. The production of other products including ammonia-urea, methanol, hydrogen and electric power is also under study.

Jan 1, 2005

By Y Yamaguchi, S Nomura, M Matsumura, C Kamijo

In order to increase productivity and decrease reducing agent rate (RAR) of blast furnaces, slag content of sinter ore must be decreased. However, gangue content in iron ore tends to increase because of resource depletion. Therefore, amount of high-grade concentrate in sinter ore feeds should be increased, but this situation causes a decrease in permeability of the sintering bed so that the productivity of sinter process decreases. In order to increase the amount of concentrate, NSSMS has developed the P-type separate granulation method, RF-MEBIOS and SPEx II technologies. These technologies have been introduced to actual sintering machines. In this report, a new technology using microparticles of iron ore is proposed to increase the amount of concentrate in sinter blends. Basic experiments simulating the sinter making process using microparticles of iron ore were undertaken. Crushed pisolite, containing >60 wt per cent -10 µm was prepared for binder. The pisolite microparticle binder was mixed with another Australian sinter feed ore in a high-speed agitating mixer. They were mixed for about one minute, and then granulated using a pan pelletiser. After that, they were added to another raw material mixed by a drum mixer, and then charged in a pot for a sinter pot test. As a result, when the amount of concentrate increased from 13 wt per cent to 20 wt per cent, productivity was almost kept constant using pisolite microparticle binder.CITATION:Kamijo, C, Yamaguchi, Y, Matsumura, M, Kawaguchi, T and Nomura, S, 2017. Development of an iron ore microparticle binder for increasing the concentrate content of sinter blends, in Proceedings Iron Ore 2017, pp 69–74 (The Australasian Institute of Mining and Metallurgy: Melbourne).

Jul 24, 2017

The paper outlines the history and current status of the VALMIN Code and sets out the background, methodology, results and recommendations of the Independent Review of the VALMIN Code undertaken during 2001 under the Chairmanship of Ian Goddard. The paper is based on the final report of the Taskforce, which was submitted to the Board of The AusIMM for consideration.

Jan 1, 2002

Modelling and Simulation to Design a Flotation Circuit for Gold Concentration

Sep 13, 2010

By R Stefansen

Stockyard operations are governed by the interaction between the different disciplines required to successfully schedule and control the supply chain of raw material through the stockyard in combination with the effectivity of the operation of the stockyard equipment. The system demonstrates a proven technology for implementing a centralised operation of full unmanned stockyard equipment, using a high precision absolute positioning system based on a Real-Time Kinematic (RTK) Global Navigation Satellite System (GNSS) receivers in combination with 3D rangefinders. The system implementation maps the surface profile of the stockyard inventory and allows in combination with proprietary algorithms for full operation of the stockyard machines without on-board operators. The operational impact of delayering the process by moving to a centralised operation is examined, together with the combined effect on the overall safety in the stockyard as a result of a change in reliance on operator skill dependencies. Average performance gains range from 10–20 per cent. The performance of the automation system is related to a consistency and reliability of uniform operation, which has an impact on the life expectancy and the effectiveness of the equipment. The effects of having instantaneous and correct information about the stockyard inventory volume measurement are investigated in relation towards spot price trading in current fast reacting markets.CITATION:Stefansen, R, 2017. Advanced automation for centralised stockyard operations, in Proceedings Iron Ore 2017, pp 105–110 (The Australasian Institute of Mining and Metallurgy: Melbourne).

Jul 24, 2017

The status of remote sensing data availability in New Zealand is outlined and discussed. Currently, two multispectral remote sensing satellites are providing regular data over New Zealand; aircraft scanner services are available from Australia.; operational radar satellite services are yet to materialise. The advantages and disadvantages of the various data types are compared and contrasted. Some image processing considerations are outlined.

Jan 1, 1993

Research on the Thermodynamics of Siderite Roast Decomposition and the Experiment of Magnetic Roasting-Separation

Sep 13, 2010

Open pit mining has considerable damaging effects on the environment of the mining region. These harmful influences have to be controlled during mining operation until mine closure. Different sections of mined land, such as; pit(s), waste dump(s), tailing pond(s), roads, areas for onsite facilities and free land zones which are not mined, have to be reclaimed through treatment of environmental pollution and implementation of a permanent post mining land use (PMLU) after mine closure. Implementation of a permanent optimal post mining land use (OPMLU) is one the most decisive criterion which effects on reclamation procedure, mine closure and their costs. Therefore to define ultimate pit limit (UPL), mine closure and reclamation costs should be entered in the calculation iterations same as the other variable costs of the projects. Estimation of closure and reclamation costs of a mining project is carried out based on the attained OPMLU and the specifications of the mine site. In this paper, a model is developed to provide OPMLU for pit area through fuzzy multi-attribute decision making (FMADM) technique. The model was implemented on a hypothetical copper mine in northwest of Iran as a case study. Lumber production was selected as OPMLU for the pit area. It is finally concluded that through the developed model, OPMLU for different sections of mined land in an open pit mine project is defined. Also closure and reclamation costs are estimated based on the defined OPMLU to achieve a more accurate UPL.

Dec 6, 2010

By H W. Wu

The objective of this paper is to examine some modern forms of auxiliary ventilation fabric ducting with streamline design fittings and the efficiency of construction practices. The most dynamic form of auxiliary ventilation is a moveable fan and ducting, which is easy to install and uses light weight fabric. The porous nature of some ducting construction results in leakage and loss of efficiency. Flexible fabric ducting is primarily associated with metalliferous mining and industrial material quarrying. Some applications are found in coal in stone/rock development and with use of dust scrubbers.Forcing auxiliary ventilation systems employing circular fabric ducting have been examined. Leakage of air from ducting is affected by ducting material and construction methodology (such as welded or sewn), quality of installation, number of joints, total length, pressure differences between the inside and outside and diameter. The best ducting system with welded construction can have up to four times less leakage as compared with some systems with sewn construction. It is also evident that the sewn type ducting will deliver less air to working faces and require more fan power, hence higher operating costs to run when connected to the same fan.A case study has also been undertaken to compare predicted operating costs of auxiliary ventilation systems connecting various types of ventilation duct fittings. The study also assesses the technical importance of streamline design with low aerodynamic resistance to reduce the shock losses of the duct fittings. It was found that the system connected with streamline designed fittings is able to provide some power cost savings and deliver more air compared with the system fitted with conventional fitting pieces.Using a ventilation ducting system with a lower leakage and frictional characteristic represents a sound solution to new challenges faced by the industry for increasing demand for better quantities and quality of air delivered to working faces; this is due to higher production schedules and stricter mine health and safety regulations within the Australian mining industry.CITATION:Wu, H W and Gillies, A D S, 2017. A comparison of auxiliary ventilation systems and their predicted operational performances, in Proceedings Australian Mine Vent Conference 2017, pp 207–214 (The Australasian Institute of Mining and Metallurgy: Melbourne).

Aug 28, 2017

By G B. Arehart, S J. Mathews, J L. Mauk

The banded nature of the quartz veins which form the Empire lode at the Golden Cross mine, is perhaps their most striking feature. Petrographic studies show that significant differences occur between the bands in terms of textures, quartz grain size, calcite, adularia and kaolinite content, and the form, concentration and mineralogy of sulfide phases.   The d18Oquartz values of individual bands within the vein material range from 7.3-10.9ë. Calculations show that the d18Oquartz values can be adequately explained by temporal variations in the system temperature, boiling and/or variations in the systems fluid/rock ratios.

Jan 1, 1995

WMC was a late entrant into Indonesia in mid-1996, but had considerable experience and success in exploring in Asia, particularly the Philippines since 1988. Given the geological similarities to the Philippines and IndonesiaÆs superior æcradle to graveÆ Contract of Work (CoW) tenure system, the entry into Indonesia was a logical decision but nonetheless a result of detailed planning. At the time of WMCÆs entry, Busang in Kalimantan was still a 60 moz wonder and the euphoria of this apparent discovery had overflowed into every aspect of exploration. Many junior mining companies and tenement speculators were clamouring for properties in Kalimantan, whilst other serious and capable explorers had to compete for properties and exploration personnel in an era of high and often unrealistic expectations. The picture in late-1998 and through 1999 is dramatically different, as the worldwide downturn in the price of most metals coincides with financial and social crises throughout most Asian countries. The impact of this has been particularly severe in Indonesia and when coupled with the negative sentiment of the Busang fraud has resulted in an exodus of junior companies and also some of the majors. This is understandable given the much publicised social unrest, uncertainty of government, mooted changes to the eighth generation CoW, increasing illegal mining and heightened community expectations. The reality however is somewhat different and although clearly a crisis in many respects, it is also a time of great opportunity.

Jan 1, 1999

By S G. Keyte

Gravity methods of recovering alluvial gold are not very efficient at particle sizes below about 0.l mm. Whereas such gold may not have been economic to recover in the past, the same may not be true today. Centrifugal concentrators, like the Knudsen and Knelson bowls, are showing promise after an inauspicious start, at least in New Zealand. The large proportion of heavy mineral in many auriferous beach sands and the natural hydrophobicity of fine gold should make flotation an attractive contender for its recovery. The conventional mechanical flotation cell is effective, but roughing, scavenging and cleaning are necessary to achieve both high recovery and low mass Yield. More problematic is the difficulty of maintaining coarse and dense sands in suspension. The air sparged hydrocyclone is effective at recovering fine gold from a fine Colarado River sand, but is not effective for the coarse and dense beach sands of New Zealand. The flotation column shows much promise for these sands, when recoveries of over 80 per cent and mass yields of less than one per cent can be achieved in a single pass. The froth separator of the USSR and flash flotation could also be worthy contenders. It is felt that flotation could be limited to naturally and artificially de-slimed concentrates.

Jan 1, 1990