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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 achievement of high availability of the Grey River Gold Mining Limited's alluvial gold dredge is a tortuous task which will rely upon the dedication of all staff employed at Grey River Gold Mining Limited (GRGML). The persistent adoption of new technology and better operating procedures, combined with a strong commitment to preventative and predictive maintenance, is necessary. The Grey River Gold Mining Limited alluvial gold dredge is operating in a relatively low grade alluvial gold deposit and hence relies on a high throughput of ore to be profitable. To achieve the required high material throughput the dredge incorporates an overburden removal system which operates simultaneously with a conventional bucketline system.   The overburden system incorporates a cutter wheel and suction pump configuration which is dedicated to removing the low grade (5 mg gold/m3 gravel) overburden. The bucketline conveys the richer grade payzone gravels (up to 890 mg/m3 gravel) to the recovery plant mounted onboard the dredge. The horizon for the overburden system approximates 15 m and the payzone terminates at the interface of the old man rock and the alluvial gravels at a variable depth averaging 22 m.   From a mechanical engineering perspective the dredge is a machine comprised of two materials handling systems which are controlled by Operations Staff and electronic process control systems.   The availability of such a materials handling system is a function of four variables: 1. The environment that the machine operates in. 2. The ability of the people operating the machine. 3. The design of the mechanisms, the configuration that they are grouped in and the effectiveness of the process control systems which control the mechanisms. 4. The procedures utilised to predict the performance of the machines and the skill of staff to analyse that data and carry out effective maintenance.

Jan 1, 1989

By R Hoskings

Conceptual studies of the run of mine stockpiling and reclaiming requirements commenced in 1975. Final selection of equipment was made in 1978 and the equipment was commissioned in June, 1979. Equipment selection was made after extensive investigation and visits to existing facilities throughout the world. The equipment selected is described and compared with the alternatives. Foundations were designed to minimise cleanup effort and to ensure stability of equipment under design wind loading without storm bays. Programmable logic control enables the stacking and reclaiming facility to provide a blended feed to the coal preparation plant.

Jan 1, 1980

By C J. Hogan

Increasing demand for fine grinding to improve mineral liberation and metal recovery and the need for stricter control of the environmental impact of tailings deposition poses problems for tailings disposal. This has led to an increasing number of investigations of properties of tailings and their disposal. This paper describes laboratory model testing undertaken on Macraes mine flotation tailings to provide information on tailings behaviour under conditions of subaerial deposition. The in-place density or 'dry density' of the impounded tailings and the impoundment depth relationship are important for utilisation of the available impoundment storage facility and results of dry density to depth relationships are given for the Macraes mine tailings impoundment.

Jan 1, 1993

By C A. Locke

Geophysical signatures of the Taranaki and Tongariro volcanoes reflect similarities in their age, composition and hydrothermal histories, but also reflect differences in host rock settings and edifice evolution. The Taranaki volcanoes have strong positive gravity anomalies showing that their edifices largely consist of dense andesite which reflects substantial lava production or dyke injection during construction and that large sub-edifice dyke/stock complexes occur. In contrast, the Tongariro volcanoes have strong negative gravity anomalies indicating low density edifices of volcaniclastic material; no sub-edifice intrusions can be identified, probably because of the lack of density contrast with host basement rocks. Strong positive magnetic anomalies over the younger cones can mainly be attributed to near-surface andesite lavas or dykes whereas subdued magnetic effects are associated with hydrothermally altered zones within both edifices and sub-edifice intrusions.  

Jan 1, 1995

The early development patterns of both Australia and New Zealand were substantially in parallel and both were heavily indebted to gold mining for, providing the stimulus to growth. However, since the mining boom, of 1895 - 1899, the mining sector in New Zealand has progressively declined, while in Australia it has assumed an increasing importance in the economy. The continued dominance of minerals in Australian trade, and the fact that eight out of the top ten companies in Australia are directly involved in mineral exploration and production, has strongly influenced government and public attitude's to the minerals sector. Although the legal framework of mining and exploration Acts and Regulations are similar it is in, the method of administration, particularly in regard to exploration and prospecting licences, that the gulf across, the Tasman is apparent. Despite the relative ease of application and granting of licences in Australia, in the more settled south eastern part of the continent we are finding more and more land is being zoned unavailable for exploration. In the remote areas, the Aboriginals now control nearly ten per cent of the land area of Australia, virtually with drawing that portion from exploration. The concept of 'Australianisation' has softened a hardening attitude against foreign investment in mining on the part of the bureaucracy. This anti-mining attitude is fortunately, not shared by the public, and we can but hope that the will of the Australian people can filter through to our masters in Canberra, and ease the rapid increase in the number of regulatory bodies which does so much to inhibit the normal conduct of business. The delays caused by interminable hearings and committee investigations all cost money. This cost can only rebound back on the end consumer, who after all is a voter.

Jan 1, 1982

By U König

The use of high speed detectors made X-ray diffraction (XRD) an important tool for quality and process control in the mining industries. Besides knowledge about the mineralogy of a sample it provides useful information in terms of quantification of the crystalline phases and the amorphous content. Cluster analysis of XRD data can facilitate multi-dimensional mapping of ore deposits and drill cores, identifying regions of favourable mineral compositions. The studies of this paper demonstrate how XRD and data clustering can be used for grade control, process optimisation and quality control of iron ores and iron ore sinters. These new developments have an enormous potential as an inexpensive, reliable tool, useful in the characterisation of iron and sinter materials implemented in an industrial environment.

Jul 11, 2011

Study on Flotation of the Low-Grade Magnesite Ore

Sep 13, 2010

Electronic noses are being used in the processing industries and in fields such as environmental and occupational hygiene to detect a wide variety of problems from contaminated foods to toxic chemicals in soils. Recently, research has been conducted into the use of these devices for detecting spontaneous combustion in mines with the aim of producing a method for early detection of a developing heating. Gas samples were collected from both SimtarsÆ 16 m3 large-scale spontaneous combustion reactor and the University of QueenslandÆs two-metre column. The samples were analysed using an electronic nose. GCMS and HPLC were used to identify some of the components present. A number of issues both from a practical mine situation and a scientific standpoint have been identified that need to be addressed before these devices can be used to detect a developing heating. Aluminised bags routinely used in the mining industry to collect gas samples for analysis of the permanent gases are not suitable for use with electronic nose devices as they have a æfingerprintÆ from the polymer lining that interferes with the coal heating fingerprint. Tedlar bags used for environmental gas sampling are also unsuitable due to their fingerprint. Gas samples can be collected in glass gas bulbs with aluminium seals and successfully analysed. However the aluminium foil used to seal the bulbs is a restricted item in underground mines. It was also found that the volatile organic fingerprint of the coal heating was extremely weak at temperatures below 130¦C. Before a useful application can be developed, further investigation into the chemical species present in the off-gases from Australian coals is required.

Jan 1, 2005

Study on a Novel Polymer/Bentonite Compound Adsorbent for Removal of Cu(II) from Aqueous Solution

Sep 13, 2010

Study on Desulfurisation and Deashing for Medium-High Sulfur Coal Using Shaking Table As important coal resources, medium- high sulfur accounts for a significant part of the coal reserve in China. The environmental regulations and fuel standard requires sulfur and ash to be removed before it is used, so as to save energy and decrease the emission. Therefore, the effective desulfurisation and deashing technologies are urgent needed. However, due to the local characteristics of the coal, specific technology with optimum operation parameters is required to develop for different local coal. Qinglong is a district of Guizhou Province, which has large medium to high sulfur contained coal reserve. In this paper, medium-high sulfur coal is sampled from Qinglong, Guizhou province. Some basic characteristics such as the mineralogical composition of the coal rock, the monomer existing state and the granulometric composition are determined by X-ray diffraction quantitative analysis and polarisation microscope analysis respectively. Adopting the classified feed method, shaking table tests show that the feed pulp concentration is 20 per cent, the stroke is 13mm, the frequency of the stroke is 380 per min, the cross slope is 3¦ and the volume of wash water is 5.2 L per min. Under such condition, aggregate processed coal yield is 72.87 per cent and sulfur content decrease to 1.31 per cent With shaking table technology of 'First stage rough and intermediate further fine benefication', the yield of concentrate coal increased from 72.87 per cent to 81.21 per cent, while the sulfur content reduced to 1.35 per cent.

Sep 13, 2010

Mining companies in order to compete and succeed in being viable business propositions must look to the future and select mining methods which guarantee improved efficiency and productivity as well as lower costs. A mining company in adopting a method of mining must now select the equipment most compatible. To some mines compatible equipment may mean the use of drilling jumbos to replace hand held rock drills or the use of load haul dump units to replace scrapers. To other more mechanised mines compatible equipment may mean the use of raise borers and road heading machines. The right decision will be where equipment compliments method in such a way that the working environment is improved, productivity is maximised, cost if reduced and all profit opportunities are optimised. An example of such is where the use of improved mining techniques in underground operations may see cut off grades reduced. By selectively mining these lower grade orebodies, smaller operation's ore reserves improve and the capacity for continued growth is enhanced.

Jan 1, 1990

concentrations) and physical nature of receiving streams, which in turn affects the stream ecosystem. Benthic macroinvertebrates are used to illustrate these impacts, and to investigate natural recovery in affected streams. In Charming Creek, a severely impacted stream in the Buller District, the macroinvertebrate community recovers diversity and the proportion of sensitive species (EPT) in the community is more significant with increasing downstream distance from the source of AMD. This is most likely due to dilution of AMD contaminated water by tributaries to the Charming Creek mainstream. Other impacted systems with less dilution from tributaries did not display similar levels of recovery. The effectiveness of remediation products BauxsolÖ and Zeolite was investigated using laboratory trials. Both products mitigated the toxicity of AMD and enhanced the survival of mayflies exposed to AMD contaminated water. Such products may be of use in the New Zealand environment but are likely to be most effective in conjunction with other systems (eg wetlands). Mitigating the impacts of AMD on stream ecosystems needs to include systems to directly address water chemistry issues (low pH, high metal concentrations) as a component of a holistic approach to restoring environmental conditions.

Jan 1, 2003

By C Noble, J Webster-Brown

A survey of selected West Coast Streams was undertaken in Summer 2001, Summer 2002 and Winter 2002 to establish the degree of arsenic (As) contamination in waters and sediments downstream of old coal and gold mine workings on the West Coast. Of the catchments studied, Soldiers/Ford Creek and Rapid Stream showed the most significant elevated As concentrations, predominantly in dissolved form, and evidence of AMD or ARD contamination (high sulfate concentrations and/or acidity). The rate and processes of removal of dissolved arsenic from the water column (attenuation) have been studied in these catchments. The Rapid Stream and Soldiers/Ford Creek catchments are directly affected by adit drainage from the Sullivan and Blackball coal mines respectively. Both catchments have high As concentrations in the sediments, with up to 770 mg/kg in Soldiers Creek and 490 mg/kg in Rapid Stream. Dissolved As concentrations are significantly elevated in the neutral pH waters of Soldiers Creek; typically as high as 100 - 200 ¦g/kg, up to 500 m downstream of the main adit discharge (800 ¦g/kg As). Adit inflows to Rapid Stream were acidic and contained 20 - 30 ¦g/kg dissolved As, with relatively high concentrations of arsenic in the stream water in winter (up to 18 ¦g/kg), but not in summer. Analysis of concentration trends and As:SO4 ratios downstream of these obvious As sources confirmed that dissolved As had been actively removed from the water column, but varied seasonally with greater removal evident in summer. Adsorption of arsenic onto iron oxide in the stream sediments is the most likely mechanism of removal. The Snowy River catchment, on the other hand, has relatively high As concentrations in both the sediments and the water column, but there was little evidence of a distinct AMD or ARD input from the Blackwater gold mining area. Preliminary investigation suggests that dilution rather than attenuation is responsible for decreasing As concentrations downstream.

Jan 1, 2003

Pilot-Plant Testing of Ammoniacal-Cyanidation for Gold Recovery from Copper Gold-Bearing Ore The results of pilot-plant tested ammoniacal-cyanidation of gold recovery from copper gold-bearing ore are presented in this paper. This ore is from a deposit of Russian Federation with gold and copper grade 9.5 g/t and 0.4 per cent, respectively. Copper is largely present as malachite and azurite. The presence of chalcopyrite and bornite is also observed. In order to recover gold, gravity is recommended. Two options of ammoniacal-cyanidation using leaching of gravity tails, CIP and filtration, were tested. It was found that ammoniacal-cyanidation using filtration of leaching tailings and recycled solutions is the most optimal option. The proposed flow sheet provides for 89.7 per cent gold recovery from gravity tailings at the consumption of NaCN 0.9 kg/t and (NH4)2CO3 7.5 - 9 kg/t. Compared to conventional cyanidation, this technology decreases the consumption of sodium cyanide from 4 up to 0.9 kg/t at the same gold recovery. It can be recommended for the treatment of copper gold-bearing ores with the similar composition.

Sep 13, 2010

By D James

Fletcher Challenge Limited through its subsidiary Grampian Mining Co Limited has carried out an ore evaluation of one of New Zealand's largest known deposits of ilmenite located at Barrytown on the West Coast of the South Island, New Zealand. The ilmenite is located in a beach sand environment which has previously been mined for gold. Two analytical techniques were developed to quantify the resource. Considerable difficulty was experienced in this phase of the evaluation due to the presence of major inclusions within the ilmenite grains. Wet and dry concentration circuits, utilising spiral, wet magnet, high tension and plate electrostatic separators have been designed to produce ilmenite from the ore. Studies to utilise the titanium content of the Barrytown ilmenite have been made. Recent work has been directed towards a titanium dioxide pigment process.

Jan 1, 1986

By W Valery, S Morrell

In the mining industry blasts are usually designed to fracture the in situ rock mass and prepare it for excavation and subsequent transport. The run of mine (ROM) fragmentation is considered good when it is fine enough and loose enough to ensure efficient digging and loading operations. Mining optimisation strategy is hence usually focussed on minimising total mining costs and maintaining these ROM fragmentation characteristics. Although this approach ensures an efficient mining operation it ignores the potential impact on crushing and grinding. Investigations by several researchers have shown that designing blasts to produce ROM fragmentation to optimise crushing and grinding performance enhances the overall efficiency and profitability (Eloranta, 1995; Kojovic et al, 1995; Bulow et al, 1998; Kanchibotla et al, 1998; Scott et al, 1998; Simkus and Dance, 1998). Field experimentation in this area is often found to be difficult because of high implementation costs and insufficient understanding about the effect of fragmentation at different stages in a comminution circuit. Modelling and simulation of blasting and comminution processes provide a more economic alternative to explore the impact of blast design changes on the down stream operations (Kanchibotla et al, 1998; Kojovic et al, 1998; Adam and Siddall, 1998; Bulow et al, 1998). However, the reliability of such simulations depends on:the ability of the models to reproduce the physical processes that take place; characterisation of rock mass in terms of its blastability and comminution characteristics; and in the case of blast modelling the ability to predict fines (-10 mm) has been found to be particularly important as this fraction has a significant effect on mill throughput.

Jan 1, 1999

By T Stambolie

Mine planning processes are continuously evolving, increasing in complexity, and are required to be developed in shorter timeframes, often missing important steps in the process. Underground coal mines are also moving into more challenging environments, with the more favourable resources having been exhausted. In addition to traditional mine planning processes there is an increasing level of complexities associated with parallel systems including the preparation of Joint Ore Reserves Committee (JORC) compliant estimates (JORC, 2012 and Guidelines Review Committee, 2014) or seeking critical regulatory development consent to undertake mining. There is a clear link between geotechnical considerations and success of mining operations, and therefore it is essential that such considerations are elevated in both status and priority. It is obvious that geotechnical considerations are paramount in any mine, however it is imperative to accept that such considerations, and the collection of information relating to such, are undertaken from the onset of any mining project. CITATION:Stambolie, T, 2018. Elevating geotechnical considerations in the Australian underground coal industry and mine planning process, in Proceedings The Fourth Australasian Ground Control in Mining Conference (AusRock), pp 383–391 (The Australasian Institute of Mining and Metallurgy: Melbourne).

Nov 30, 2018

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

Who Macraes Mining Company Limited is can be summed up by the following statements: +         We have been New Zealand's largest gold producer for seven years +         We have one of the lowest market capitalisation per reserve ounce of the gold producers in the  Australian Gold Index +         We have a resource finding cost of less than NZ$l0 per ounce +         We have a large land bank with proven reserves +         We have an Operating Cash Margin of approximately NZ$200 per ounce +         We have reduced our Dry Milled Tonne Cost by 34% since 1992   Our Mission is to continually grow our gold business, through maximising cashflow and focusing on our value drivers being: +         Increasing reserves +         Increasing cash operating margins +         Increasing production   The real challenge is the reduction of operating costs and the optimisation of revenue, particularly in the current gold price environment.   The Company has as at 31 December 1996 total mineral resources of 6.1 million ounces and reserves of 3.4 million ounces. This together with our current cash position of approximately NZ$15 million and strong hedging book of approximately 800,000 ounces places the Company on a sound financial footing whilst positioning itself to aggressively pursue its growth strategy when gold price and market conditions improve.

Jan 1, 1997