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By E Coffison, M Gibbs, C Bennett

The sustainable management of surface water associated with coal mining and coal seam gas projects is a considerable factor affecting the global competitiveness of these resource companies operating in Australia. Management of surface water can be costly, but effective water management and hence environmental stewardship enhances corporate social responsibility and the social license to operate. The surface water issues for the two industries are comparable, yet there is currently a lack of alignment between how Queensland, where the majority of AustraliaÆs coal seam gas projects are located, manages and regulates water on coal mine projects and coal seam gas projects.This paper provides a high level comparison of Queensland legislation and highlights the lack of alignment of this legislation regarding surface water management in these two industries. Through a case study, it looks at the surface water management process at a coal mine site based on the current legislation and principals of surface water management. QueenslandÆs lack of alignment in legislation regarding surface water management in these industries is understandable given the different development paths and time scales of the two industries. The coal mining industry has developed over a long period of time and the legislation has progressed in parallel, whereas, the coal seam gas industry is relatively new in Australia and the legislation has had to advance quickly. The lack of alignment between management of surface water for the two industries creates confusion among stakeholders and this adds complexity and additional transaction costs during the exploration, permitting and operational phases of projects, including landowners who may be affected.CITATION:Bennett, C, Coffison, E and Gibbs, M, 2013. Lack of alignment between regulation of surface water management in coal mining and coal seam gas, in Proceedings Water in Mining 2013 , pp 157-162 (The Australasian Institute of Mining and Metallurgy: Melbourne).

Nov 26, 2013

Geostatistical literature has been dealing with recoverable reserve estimation techniques for the last 30 years. There have been well established support correction techniques (Le. affine correction, indirect log-normal correction, etc.) to deal with volume -variance relationship globally in determining what will be the reserves above a cutoff grade during mining. Kriging has become the accepted technique in the mining industry for ore reserve estimation. Many large companies are using this method for gold and copper deposit modeling. In general, the estimates coming from kriging are smooth. The variances of the block grades estimated by kriging are often lower than the material that will be mined selectively. As a result, kriging tends to under estimate reserves at high cutoff grades and overestimates them in low cutoff grades. It is necessary to perform additional steps after kriging if the goal is to determine recoverable reserves at some cutoff and not the in situ resources. In the mining industry, it is becoming more and more common for the low grade heap leach projects to consider whether the higher grade portion of a deposit may be processed by a mill at higher profits. Similarly, a concentrator -refinery operations are implementing heap leach -SX-EW option for the lower grade portion of their deposit. These options are making it very critical to estimate the low and high end of the grade distributions more accurately. Ore reserve estimation is normally done by using widely spaced exploration data which has very small size support (Le. core samples). Selective mining is carried out on ore control that is based on closely spaced blasthole data normally averaged into larger polygons based on some cutoff grade. Estimated grades from exploration data need to reflect the variability of the grades of the selectively mined units if they are used without further adjustments to predict recoverable reserves.

Jan 1, 1997

By M. Pötsch, W. Schubert

"The kinematic analysis of rock blocks is one part of a block stability assessment. It provides information about a block’s movability, i.e. if a block can detach from the adjacent rock mass and move towards the free space. This paper introduces an analytical method for the analysis of pure rotations of arbitrary finite polyhedral blocks. It enables the engineer to judge a block’s rotatability about a corner or an edge. The method is presented using a graphical and computational method. The application of the method is illustrated with an example. INTRODUCTIONThe kinematic analysis of rock blocks deals with the determination of the movability of blocks. Established methods typically cover: (a) translational motion (John 1968, Markland 1972, Londe et al. 1969, 1970, Goodman & Shi 1985, Warburton 1981) and (b) the specific rotational cases Toppling (Goodman & Bray 1977) and Slumping (Kieffer 1998). Mauldon & Goodman (1990, 1996) and Tonon (1998) introduced rotational kinematic analyses for three-joint pyramids and tetrahedral blocks extending Goodman & Shi’s block theory.All mentioned methods are subject to assumptions that limit the applicability to engineering problems. For example, the kinematic test of daylighting joints or intersections inherently assumes a finite block, which only can be proved by the finiteness theorem (Goodman & Shi 1985). Daylighting of an intersection or plane is not a sufficient condition for removability. Goodman & Shi’s and Warburton’s methods are limited to translational block motion. The methods for block rotations so far address tetrahedral blocks only. They also address only pure rotational modes and neglect the general motion of a rigid body. This paper introduces an analytical method for the analysis of the kinematic rotatability of finite rock blocks. It extends Mauldon's and Tonon's theory of rotatability of tetrahedra to arbitrary polyhedral blocks. A graphical method using the stereographic projection and a computational method are presented."

Jan 1, 2015

By F. Habashi

"A short account will be presented on the extraction of rare earths from monazite sand, bastnasite ore, and phosphate rock of igneous origin. This includes mineral beneficiation, leaching methods, fractional crystallization [of historical interest], ion exchange, solvent extraction, precipitation from solution, and reduction to metals. INTRODUCTIONOriginally, the term rare earths was only used for the oxides, R2O3, which are similar to one other in their chemical and physical properties and are therefore difficult to separate. Within the rare earth group, the elements scandium, yttrium, and lanthanum differ in their atomic structure from the elements cerium to lutetium (the lanthanides, Ln). Scandium occupies a special position with respect to this classification and its other properties, and therefore does not belong to either of these groups. The rare earth elements always occur in nature in association with each other. The isolation of groups of rare earth elements or of individual elements requires costly separation and fractionation processes owing to the great similarity of the chemical and physical properties of their compounds, which explains why the history of their discovery has extended over such a long period.The word “rare”, when used to describe this group of elements, originates from the fact it was thought that these elements could only be isolated from very rare minerals. Considering their abundance in the Earth’s crust, the term rare is now inappropriate. These elements are lithophilic and are therefore concentrated in oxidic compounds such as carbonates, silicates, titano-tantalo-niobates, and phosphates.The abundance of the rare earth elements taken together is quite considerable. Cerium, the most common rare earth, is more abundant than cobalt. Yttrium is more abundant than lead, whereas Lu and Tm are as abundant as Sb, Hg, Bi, and Ag. For all practical purposes promethium does not occur in nature. It forms only in nuclear reactors."

Jan 1, 2012

By Martin G. Casto

Mixer-settler extractors, among the oldest forms of extraction equipment, have been used since the beginning of this century. Over the past years, a very large number of mixer-settler devices have been designed and operated. Both batch and continuous flow mixer-settlers have been used. The continuous flow mixer-settler extractor offers a great number of advantages over other extraction equipment. The main advantage of the continuous flow mixer-settler is that it is a compact device. A large number of stages can be assembled in a relatively small area, and more stages can be added fairly easily. Many improvements have been made in the design of mixer-settlers. These improvements occurred in almost every phase of mixer-settler' operation; interface control, mixer design, intrastage pumping, interstage flow of the two liquid phases, and stage construction. It is believed that Barstow1 used one of the first continuous mixer-settler extractors. This mixer-settler had concurrent flow within each stage and countercurrent flow overall. The flow for both phases took place by gravity. The Barstow device and other early mixer-settlers had no separate interface control for each stage, therefore, "tilting" of the stages was necessary. In 1934 Holley and Mott2 designed a mixer-settler in which the heavy phase was recirculated within each stage by the use of a valve controlled central line instead of by a pump. Gordon and Zeigler3 in 1939 were among the first to use an adjustable valve to control the interface levels in a mixer-settler, making tilting of the extractor unnecessary. In 1952 Coplan et al. 4 used a modification of the Holley-Mott idea to build a highly improved mixer-settler with flat common walls, and with the

Jan 1, 1971

By R. L. Grayson, S. S. Peng

"Abstract. Sampling of respirable dust and analyses of samples have been partially completed for a longwall panel. Physical and compositional properties which have been characterized include:l. Respirable mass concentration, 2. Mineral composition,3. Particle size distribution by mineral,4. Particle shape distribution by mineral,5. Particle angularity distribution by mineral, and6. Respirable size distribution.Analytical techniques used in the characterization of samples are described, and results are reported with emphasis placed on relationships between the various characteristics and worker locations. Details of existing mining conditions, equipment arrangements, dust control methods and operating system parameters are presented.INTRODUCTIONThrough the work of many researchers worldwide, the health of coal miners in modern societies is now protected from dangerous exposure to respirable coal mine dust. A vast amount of research culminated in the exposure-response model of Jacobsen, et al. (1971) whi3h has been used to establish the 2mg/m exposure limit in the United States. According to the model, exposure to respirable dust for 35 years at this level or less would prevent the occurrence of a clinically significant case of coal workers' pneumoconiosis (CWP). The exposure limit, of course, must be adjusted whenever greater than five percent free silica exists in the respirable dust.The Jacobsen model was built around a mass concentration exposure, which showed the highest correlation with incidence and progression of CWP. As Morgan; et al. (1973) noted, howev.er, the quantity of respirable dust inhaled is not the only significant factor. It is noted that although mass of respirable dust correlates highest with the incidence of CWP, it is not a causal factor. Indeed, the insidious processes causing the disease occur on the cell-particle scale, requiring microscopic investigation."

Mar 1, 1989

By Pan Zhao, Yan-Nan Wang, Fei-Long Liao, Can Cai, Kai-Song Wu

"What are the basic physical parameters and main geometric parameters that are capable of representing the microscopic characteristics of rock? How can these parameters be used to accurately describe the macroscopic mechanical behavior of rock? With such questions in view, and based on the microcosmic structure analysis of rock slices, this paper presents a rock skeleton-pore structure model, holding that rock's mechanical behavior depends on the properties of rock skeleton materials and the form, size and distribution pattern of pores. According to rock stress and deformation behaviors, and in line with the skeleton-pore structure model, an essential mechanics theory for rock is advanced. The assumption that the skeleton materials are incompressible in volume and an introduction of logarithmic strain, generate the relation between porosity and apparent strain. Then, the notion that positive damage and negative damage are represented in terms of porosity is put forward; threshold value of porosity is derived by the damage threshold value of apparent volume strain; a general damage variable of rock is obtained; eventually, with the skeleton-pore model as the groundwork, a global damage constitutive equation is developed, which, with definite physical significance and material parameters to be easily determined, is convenient to apply. It has been proved that the results calculated with this new equation are well in agreement with experimental results.INTRODUCTIONRock is a form of material that contains pores, cracks and skeletons. Skeletons are composed of particles and cements. Pores or cracks within rock actually undermine the assumption of material continuum in solid mechanics. Hence, grave errors — or even false results — are inevitable if some solid mechanics theory is quoted in the discussion of rock mechanics. Many researchers in the field of rock mechanics have attempted various remedies, but the outcome is far from satisfactory — a mechanics theory for rock, in its true sense, has not been established."

Jan 1, 2015

By Andrew Lewis, Amarit Nitaramorn, Alexander Garcia, Peter Altounyan

"Indonesia is a major coal producer, the vast majority being sourced from opencast operations. Underground production to date has been constrained by unfavorable ground conditions and limited local experience. However, an underground trial in East Kalimantan has now shown that it is possible to successfully extract coal and mine safely, despite the technical challenges.A trial drift mine has been worked to a current maximum depth of 160 m (525 ft) in a dipping coal seam. The 3 m (10 ft) thick coal seam is overlain by very weak mudstone and sandstones. The mudstone forming the immediate seam roof strata proved a particular challenge given its adverse reaction to water and overall friability.Rock bolts were used as roadway support, the system being carefully selected to optimize effectiveness. An innovative method of partial extraction was trialed, which demonstrated the potential for productive mining despite the ground conditions. Roof falls have occurred within the working area, and roadways demonstrate reasonable stability over time.Throughout the course of the trial, strata behavior monitoring has been an important aspect, and a comprehensive ground control monitoring system is in place. This has enhanced the ability to increase the level of support where required and to react to deteriorating conditions. In addition, monitoring information has allowed a quantitative assessment to be made of the technical feasibility of future full-scale mining.INTRODUCTIONWith current production at over 200 million tons, much of this destined for overseas markets, Indonesia is the second largest exporter of coal (Ritschel and Schiffer, 2007). The majority of the coal is sourced from the Kalimantan coalfields. Mining is predominately opencast, yet in recent years there have been attempts made to introduce underground operations. This move would permit continued access to good quality seams that are beyond the reach of viable opencast mining."

Jan 1, 2010

By I. Filippova, L. Filippov

"The by-product potential of light rare-earth elements (LREE, La, Ce, Nd) and rare-metals (W, Nb, Sn) within the St Austell kaolin deposits (UK) is related to the kaolinisation process, which liberates the accessory heavy minerals of the host granite in the clay matrix and allows their separation in the waste streams. As a consequence these minerals are pre-concentrated in the micaceous residue which displays relatively high LREE content (around 170 ppm) hosted by monazite which is mainly distributed (up to 95%) in the -100 µm fraction. A combined gravity/flotation concentration flowsheet, starting with classification of the residue into 3 size fractions (+150 µm, 150-53 µm and -53µm) was developed. This study presents the results of the clay-rich -53 µm size fraction beneficiation by flotation using sodium oleate and hydroxamate as collectors.The effect of dispersant addition during de-sliming operations on flotation efficiency was also investigated. The LREE grade in the floated product obtained with sodium oleate increased from 3370 ppm to 5350 ppm and recovery from 30% to 80% with dispersant which is attributed to clay coating. Comparison of flotation performance and Falcon Ultra-Fine (UF) concentration of monazite to previous results obtained with Falcon Semi-Batch (SB) gravity concentrator on the unscreened raw residue clearly shows that flotation of the fine residue is more efficient than Falcon UF and Falcon SB. Indeed Falcon UF produced high recoveries (87-95%) but with almost no enrichment (1.3-1.4 ratios) whereas Falcon SB concentration of unscreened residue produced higher grades (up to 0.6 % LREE) but with low recoveries (17-22 %). These preliminary results show that LREE can be pre-concentrated suggesting that the micaceous residue stream (and the associated tailings dams) could be considered as a potential resource for these metals."

Jan 1, 2016

By C. Guney Olgun, Mohammad Khosravi, Daniel W. Wilson, Deepak Rayamajhi, Scott A. Ashford, Shuji Tamura, Ross W. Boulanger

"Dynamic centrifuge tests were performed on unimproved and improved soil with soil-cement column models. The reinforcing effect of isolated soil-cement columns for reducing liquefaction potential and ground deformation in improved soil were investigated. This paper presents the observed acceleration, pore pressure, and settlement responses under an earthquake base motion for both unimproved and improved soil models. In addition, lateral reinforcing effects of soil-cement columns were also investigated in terms of site stiffening effects and the increasing natural frequency of improved soil. The test results show that the soil-cement columns were rather ineffective in preventing liquefaction triggering in improved soil and in significantly reducing the magnitude of the resulting soil settlement compared to the model with unimproved soil profile. Furthermore, the predicted natural frequency of the improved soil profile estimated using existing design equations is shown to be significantly higher than the observed natural frequency inferred from centrifuge tests results. These design equations assume shear strain compatibility between the columns and the surrounding soil. On the other hand, revised design equations that account for shear strain incompatibility between column and surrounding soil are shown to give reasonable estimates compared to the observed natural frequency of the improved soil model.INTRODUCTIONGround improvement using stiff columns (e.g., stone columns, deep-soil-mixing columns, and jet-grout columns), are often used in practice to reduce liquefaction potential (and associated deformations) in loose soil sites. Typically, saturated silty soils are difficult to densify or drain rapidly due to their lower hydraulic conductivity, so densification and drainage techniques of improvement are often found to be ineffective. Instead, the shear reinforcing mechanisms of stiff columns are considered effective for reducing the seismic stresses and strains, and thereby reducing liquefaction potential in the enclosed saturated silty soils (Baez 1995, Adalier and Elgamal 2004, Mitchell 2008)."

Jan 1, 2015

By R Jia, J T. Waldram

"The Caijiaying lead zinc mine is located in China, north-west of Beijing, in Hebei Province. The region experiences severe winters, below -35°C, and warm summers, up to 30°C. The mine and concentrator commenced operations in the second half of 2005 with a conventional tailings disposal system consisting of a tailings dam with peripheral ring main discharge and central water recovery. A second similar dam sharing one common wall was added later. In view of the extreme winter conditions tailings lines and ring mains plus spigots, together with return water lines, require insulation and electrical trace heating. The volume of process water trapped as ice in the tailings dam ponds each winter is significant. This seasonal variation presents a major difficulty in the management of process water availability. Although Caijiaying is an underground mine there was no backfill plant at the start of operations. As plant throughput increased more quickly than originally anticipated, tailings storage capacity became a prime concern. The construction of a backfill plant in 2007 reduced the pressure on surface tailings storage area requirements, but as suitable land on which to construct further tailings storage was both expensive and difficult to acquire, a more efficient use of the available area was required. Dry tailings storage, where flotation tailings are filtered to provide an immediate return of process water plus ‘dry’ tailings filter cake for stacking, provided an answer to both the land area required, and the water management difficulties. The paper details the reasoning behind the change and the benefits obtained at Caijiaying by moving from ‘wet’ tailings storage to ‘dry’ tailings storage.Citation:Waldram, J T and Jia, R, 2016. Caijiaying Dry Tailings Storage, in Proceedings 13th AusIMM Mill Operators’ Conference 2016, pp 379–382 (The Australasian Institute of Mining and Metallurgy: Melbourne)."

Oct 10, 2016

By Jonkion M. Font

An expression for the distribution ratio of arsenic between slag and copper matte or liquid copper was developed by both, an extension of the Reddy-Blander model for deriving a priori the arsenic capacity, and by a relationship between the arsenic capacity and the arsenic distribution ratio. In this study, the a priori arsenic capacities in the FeO-SiO2, CaO-SiO2, MgO-SiO2, FeO-CaO-SiO2, FeO-FeO1.5-CuOo.5-MgO-SiO2, FeO-FeO1.5-CuO0.5-CaO-MgO and FeO-FeO1.5-CuO0.5-CaO-MgO-SiO2 slags were calculated at 1573 K. The a priori arsenic distribution ratio between the FeO-FeO1.5-CuO0.5-CaO-MgO-SiO2 slag and copper matte (L s/m as), and between the FeO-FeO1.5-SiO2 or FeO-FeO1.5-CuO0.5-CaO-MgO slag and liquid copper (L s/Cu as) were calculated. The model calculated data are found to be in good agreement with the reported experimental data. The availability of reliable thermodynamic data for slag components and impurities in the slag-matte-metal system is essential for the accurate prediction of impurity capacities and distribution ratio data. The arsenic distribution ratio model developed here, can be extended for prediction in multi-component slags and mattes or liquid metal, and thereby may lead to the development of new slag systems for the efficient removal of arsenic in the copper smelting, converting and refining processes.

Jan 1, 2003

By J W. Dong, Y M. Li, J L. Tian, Z H. Jiang

Electroslag remelting is widely used to produce various special steels, mainly because of its ability to provide high cleanliness and excellent homogeneity of ingot. Undoubtedly an optimal slag plays a key role in removing inclusions and enhancing the mechanical properties of a specific special steel. In order to improve the metallurgical performance of the slag in electroslag refining of die steel, a variety of slags have already been developed using traditional trial-and-error methods. Nonetheless, these slags may not be inherently optimal for the specific requirements of actual die steel refining processes. In this work, we have designed a CaF2-CaO-Al2O3-SiO2-MgO quinary slag system using genetic algorithms method aiming to remove the existing large size inclusions (D and Ds type) in high quality die steel. The comprehensive effects of five components (CaF2, CaO, Al2O3, SiO2 and MgO) were studied based on existing fundamental theory. The slag composition was screened considering the parameters such as melting point, electrical conductivity, calcium ion concentration, and appropriate viscosity etc. Furthermore, the candidate optimal slag was applied in the industrial production of die steel by electroslag remelting method. The detection results indicate that majority large inclusions (D and Ds type) have been successfully removed, showing significant advantage to traditional slags. This result has demonstrated the genetic method to be efficient and reliable. In addition, depending on the personalised demand of other steel and alloys, this method allows for the adjustment of the screening frameworks and processes to develop the candidate optimal slags. This method has not been reported previously in the field of electroslag composition design, and compared with the traditional trial-and-error method, the new method will save a lot of time and experimental costs.

Jun 19, 2024

By Jonkion M. Font

An expression for the distribution ratio of arsenic between slag and copper matte or liquid copper was developed by both, an extension of the Reddy-Blander moderl for deriving a priori the arsenic capacity, and by a relationship between the arsenic capacity and the arsenic distribution ratio. In this study, the a priori arsenic capacities in the FeO-SiO2, CaO-SiO2,MgO-SiO2, FeO-CaO-SiO2, FeO1.5-CuO0.5-MgO-SiO2, FeO-FeO1.5-CuO0.5-CaO-Mgo and FeO-FeO1.5-CuO0.5-CaO-Mgo-SiO2, slags were calculated at 1573 K. The a priori arsenic distribution ratio between the FeO-FeO1.5-CuO0.5-CaO-MgO-SiO2 slag and copper matte mn (Lx, )' and between the FeO-FeO1.5-SiO2 or FeO-FeO1.5-CuO0.5*-CaO-Mgo slag and liquid copper (Ls/cua) were calculated. The model calculated data are found to be in good agreement with the reported experimental data. The availability of reliable thermodynamic data for slag components and impurities in the slag-matte- metal system is essential for the accurate prediction of impurity capacities and distribution ratio data. The arsenic distribution ratio model developed here, can be extended for predication in multi-componet slags and mattes or liquid metal, and thereby may lead to the development of new slag systems for the efficient removal of arsenic in the copper smelting, converting and refining processes,

Jan 1, 2003

By W. A. McKinney

Bureau of Mines Research has demonstrated that it is technically feasible to segregate oxidized copper ores by use of a direct-fired, refractory-lined rotary kiln. Previously, the segregation process had been effected only in much more complicated indirect-fired, stainless steel kilns, The method comprises heating crushed ore premixed with small quantities of salt and carbonaceous material, such as coke, to about 830° C to produce copper as fine flake and metallic films on the surface of the coke particles. After grinding of the cooled furnace calcines, the copper is recovered by conventional flotation. During direct-fired segregation it was necessary to closely control the air-gas mixture in the burner. Good copper recoveries were obtained only when adding air in the limited range of 1.15 to 1.2 times the theoretical amount required for combustion of the natural gas. Batch trials of the new technique on quartzite-, limestone-, sandstone-, and limonite-type oxidized copper ores containing from 1.4 to 6.2 percent copper yielded flotation concentrates containing from 3.7 to 45 percent copper, representing 84 to 95 percent recoveries. Analyses of the furnace gases showed that loss of copper by volatilization was negligible. The preliminary direct-firing segregation studies were complemented by continuous runs on the quartzite ore, containing 1.4 percent copper, in an integrated segregation-flotation pilot plant having a 60 pound-per-hour capacity. In a typical test, 84 percent of the copper was recovered in a cleaner flotation product containing 25 percent copper. The study will be continued to further delineate the conditions for good segregation as effective use of standard ceramic-lined kilns will render the process more attractive from a commercial standpoint.

Jan 1, 1963

By Saeid Pournaderi, Ahmet Geveci, Ender Keskinkilic, Yavuz A. Topkaya

"This study investigated calcination behavior of one of the Turkish laterite deposits, which was recently found in Sivrihisar region. Representative limonitic laterite samples (1.26% Ni) taken from Yunusemre Karasivritepe and Kucuksivritepe location were first subjected to drying. Removal of chemically bound water and other volatiles were then studied, in detail. In the calcination experiments, temperature and time were the main experimental variables. Thermal treatment was conducted at the specific temperatures in 250 °C - 800 °C range. The weight losses due to elimination of chemically bound water and other volatiles were reported to be approximately 10 per cent of the weight of the ore. For the particle size used in the current work, 700 °C and 40 minutes were determined to be the optimum calcination temperature and time, respectively.IntroductionThe nickel ores that are economically valuable can be grouped into two categories: sulphide type nickel ores and oxide type nickel ores, namely laterites. Over all reserves in the world, 40% are sulphide nickel ores and the remaining 60% are laterites [1]. Pyrometallurgical nickel extraction from sulphide type nickel ores is conducted via matte smelting. More recently, laterite ore bodies have been subjected to nickel extraction. Depending mainly on the chemical composition of the laterite and the process economics, various extraction techniques have been implemented: pyrometallurgical route involves ferronickel smelting. High pressure acid leaching (HPAL) is the commercial method for hydrometallurgical nickel extraction, while ammonia leaching (CARON Process) is a combination of pyrometallurgical and hydrometallurgical processes [2]. With the improvements in these processes, it is predicted that laterite’s share in the world nickel production will rise to 50% in 2012, while it was reported to be 42% in 1,200,000 tons of annual production in 2003 [3]."

Jan 1, 2011

By W. B. Burchall

Introduction In presenting this paper the author wishes to state that the opinions here given represent only his personal views. A general survey of the subject has been attempted, but such deductions as may have been drawn are not necessarily endorsed by the Company with which he is associated. The aeroplane as an instrument of transport is yet a novelty, for it is only twenty-five years since man first flew. This statement, by itself, may be very deceptive, for compared with the steam locomotive or even the auto-mobile, this infant in industry has made some remarkable showings. The 'actual performance' speed-curve of aircraft plotted over a ten-year period is rising faster than the 'expectancy' speed-curve of 1924 indicated, and it should be noted that, today, the possibilities of 600 miles per hour provoke less scepticism than did the prophecies of 400 miles per hour only a decade ago. Commencing with the remarkable achievement of raising one man into the air, aircraft with an all-up weight of 14 tons are now in daily use on the British airways, and recently a non-stop flight of 5,340 miles was accomplished in an aeroplane, without refuelling. More true than ever is the statement that the records of yesterday are commonplace tomorrow, for new ideas are today seized on and exploited to the utmost once the period of scepticism and doubt has been overcome. In fact, so many new ideas have been brought forward, during the past few years, and applied successfully in our economic life, that one may well ask if today we are not a little too impatient, too exacting in demands, forgetting that real worth-while progress -is attained by no short-cuts.

Jan 1, 1933

By S. Hosein, W. Birch, C. Johnson

The widespread adoption of electronic detonators has given rise to the development of linear superposition to control the environmental impact on both third-party properties and residents resulting from blast induced vibrations. Linear superposition has become a very effective tool in the hands of blasting engineers and has enabled aggregate reserves to be accessed that once had to be abandoned. This in turn has resulted in more and more complex blasting pattern to be developed that contain multiple rows and multiple decks all with different maximum instantaneous charge weights of explosives. This is then made more complex by having to consider multiple sensitive locations often with different Peak Particle Velocity vibration limits. This paper is a case study of what did happen when a blast was designed that “pushed the boundaries” of environmental blast vibration design and control, without taking fully into account the fundamental geophysical properties of seismic waves. The resulting blast design caused a greatly enhanced s-wave to be created in a critical direction from the blast pattern. The root cause being the s-waves from earlier detonating decks in the blast pattern arriving within 2 milliseconds of decks detonating later in the blast pattern. 209 individual decks were fired in the blast pattern of which 41 pairs of decks arrived at the observation location less than 2 milliseconds apart when taking into account the s-wave speed and direction. The lesson to be learned when using electronic detonators to limit ground vibrations from complex blasting patterns, is that it is just not good enough to look at the planned firing times, a professional blasting engineer must also understand the likely interaction of the various seismic wave types created and their combined impact on any given monitoring location.

Jan 1, 2024

By K Williams, G M. Evans, S M. Iveson, K P. Galvin, C E. Loo

The Australian Research Council (ARC) has recently established an Industrial Transformation Research Hub in the area of iron ore, focused on iron ore characterisation, beneficiation, materials handling and end-use functionality. The research hubs are part of a new initiative aimed at building stronger relationships between industry and universities, while addressing issues of national significance. The ARC Research Hub for Advanced Technologies for Australian Iron Ore will focus its attention on developing innovative approaches for creating enhanced value across the full value chain through the characterisation of different ore types, beneficiation and materials handling and transport. This hub brings together five industrial organisations and a research team formed from well-established research groups based at the Newcastle Institute for Energy and Resources. These groups have a record of working closely with industry to create opportunities. Examples include new beneficiation technologies such as the Reflux Classifier for achieving gravity separation, the expertise of TUNRA Bulk Solids in materials handling and the Iron Making Centre at Newcastle, which is a capability maintained by BHP Billiton following the closure of its Technology Centre in 2009. The purpose of this paper is to provide an outline of the research hub and its objectives, some background on the research groups that now form the hub and an insight into the strategy adopted for developing and implementing new technologies. The paper also describes a range of novel technologies that have the potential to be developed and applied to iron ore beneficiation.CITATION:Galvin, K P, Roberts, A, Loo, C E, Evans, G M, Williams, K and Iveson, S M, 2015. Australian Research Council research hub for advanced technologies for Australian iron ore – an introduction, in Proceedings Iron Ore 2015, pp 7–12 (The Australasian Institute of Mining and Metallurgy: Melbourne).

Jul 13, 2015

By Matthew Price, Laura Brown, Atulya Verma, Samantha Espley

Burst-prone conditions are a significant hazard in deep hardrock mines, elevating the risk to excavation stability and, more importantly, to worker safety. As mining progresses deeper, induced stress changes may trigger the initiation of rock failure processes which can be detected and recorded as mine seismicity. The implementation of seismic monitoring and routine seismic data analyses enables mine seismicity to be quantified spatially, temporally and on scale. The ability to quantify and characterize mine seismicity offers the opportunity to gauge seismic hazard, identifying high risk zones for mitigation against burst-prone excavation failure. Over the last decade, the Mines Technical Services (MTS) group at Vale Canada Limited’s Garson Mine assessed seismic hazard with the objective of assigning practical mitigating controls to zones identified as having a high rockburst potential. Initially, seismic hazard was computed using the Seismic Excavation Hazard Mapping (SEHM) software developed by the Mining Innovation Rehabilitation and Applied Research Corporation (MIRARCO) at Laurentian University, Canada. More recently, Vale Sudbury Operations partnered with the Australian Centre for Geomechanics and the University of Western Australia’s mXrap consortium. Through the consortium partnership, MTS at Garson Mine implemented the mXrap seismic data analyses platform, including the grid-based seismic hazard assessment tool. Building on 10 years of seismic hazard assessment experience at Vale Garson Mine, this paper summarizes a comprehensive case study, comparing the two tools (SHEM and mXrap) used at Garson Mine to assess, quantify, and represent seismic hazard. Subsequently, results of the Garson Mine comparative seismic hazard study will be discussed, emphasizing the need for an all-inclusive hazard assessment tool, focused on delivering practical mitigating controls that further enhance the overall safety of seismically active underground mines.

Apr 26, 2022