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The high cost of sampling systems is largely due to the fact that indiv- idual mechanical type sampling units must be installed at the discharge end of ore/pulp pipelines, that is, at points where the pipeline discharges into pump sumps or the like. A considerable economic advantage may be obtained in the use of a samp- ling device that can be installed at any point in the path of the trans- porting pipe line. Initial tests on a vertical line with an injection sampler using iron ore concentrates reveal the validity of this type sample versus that taken with a mechanical sampler. A descrip- tion of the injection sampler shows its simplicity of installation, requir- ing minimum downtime on existing lines.

Jan 1, 1976

By Quinlan M. J, Ratcliffe J. S

Chemical kinetics is a dependent process which usually correlates the rate at which a reaction proceeds with the mechanism descriptive of the manner by which reactive particles interact. Given the latter, the object gen- erally is to find the reaction rate dependency in terms of an intensive property of the system - number of reactive particles present, and of the energetics of the system - usually temperature. Chemical kinetics depend on a dem- onstration that reaction considerations alone control the phenomenological process under study. For these rea- sons, chemical kinetics are usually involved in homogeneous gaseous systems. Even in liquid homogeneous sys- tems earliness or lateness of reactant mixing rather than chemical kinetics may be controlling. Considerations of transport phenomena are involved in heterogeneous systems and often control the observable rate:an additional problem in such systems is to apportion the rate due to mass transfer - usually a linear process - and that due to reaction which may be linear or non-linear. Experimentally, conditions are often chosen so that only one consideration controls but this becomes more difficult where solid phases are involved. Kinetic modelling involves considerations of chemical kinetics, transport phenomena, and factors attributable to the physical environment in which the process takes place. The latter two considerations may be quite different as between experiment and plant. The kinetic model may be a mathematical representation of a conceptual mech- anistic model of the reaction. Alternatively, it may be an empirical relationship resulting from, for example, some curve fitting procedure applied to experimental data. The latter approach may be necessary where the system is particularly complicated.

Jan 1, 1975

By M Costa, L Polizzi

Process optimisation and continuous improvement are usually acknowledged when making a process more effective, efficient and transparent. During the last few decades, thousands of companies around the world have used total quality concepts in order to establish a continuous improvement process in their companies. Typically these companies apply some kind of Kaizen-type tools and expect results in the short term; however, the great majority of companies are poorly implementing these continuous improvement programs.Usually the most common reasons for failure of the program are lack of commitment from leaders, lack of discipline and engagement from the team to follow process and lack of clear targets for the program. When the results do not come at the expected timeline, it is common to simply drop the current process and apply a different approach from another company or consulting firm.This paper will explore some successful cases of companies that have invested time and effort to establish a reliable and sustainable process of continuous improvement. The focus will be case studies of mines and smelters around the world that use the plan–do–check–act (PDCA) cycle to increase productivity with the best services and lowest costs. The main tools and processes used by these companies will be discussed, as well as results achieved.CITATION:Costa, M and Polizzi, L, 2014. Introducing and sustaining a continuous improvement program in mines and smelters, in Proceedings 12th AusIMM Mill Operators’ Conference 2014 , pp 55–62 (The Australasian Institute of Mining and Metallurgy: Melbourne).

Sep 1, 2014

The explosion at Appin Colliery on July 24th, 1979, demonstrated the need for a large scale facility to simulate an underground type explosion and study its effects. The effects of an explosion cannot be established quantitat- ively using small scale models. A gallery was constructed for this purpose at Londonderry Centre and commissioned in Feb- ruary, 1980. It is 50 metres long, 2.7 metres in diameter, capable of withstanding an internal pressure of 210 kPa and is the only facility available for this purpose in Australia. The gallery has provided valuable inform- ation on blast effects of explosions in tunnels and is to be used for testing the performance of explosion arresting devices, further invest- igation of explosion effects, research into basic explosion phenomena and instrumentation development. Additionally, it will provide a demonstration facility for training purposes.

Jan 1, 1981

By M Berry

Consider these four questions:What is the definition of life-of-mine?When should life-of-mine planning seriously commence?When can life-of-mine planning seriously commence?What is the key input to effective life-of-mine planning?Whilst there is likely to be general consensus on the answers to the first three questions, the answer to the fourth question is open to debate. This author argues that understanding and managing risks and opportunities associated with geological uncertainty is the key input to effective life-of-mine planning, at all stages in the life cycle of a mining project.CITATION:Berry, M, ?2014. Effective life-of-mine planning by understanding and managing risks and opportunities associated with geological uncertainty, in Proceedings Life-of-Mine 2014 , pp 183–190 (The Australasian Institute of Mining and Metallurgy: Melbourne).

Jul 16, 2014

By Van Hoorn PD

For the development of BHP's Gregory open cut coal mine in Central Queensland a mini computer was successfully used to assist staff in the evaluation of the deposit and the planning of the mine. The Gregory deposit is essentially a single mineable seam deposit, however the systems developed may be applied to other coal deposits including multi seam occurences. The first phase of the Gregory computer evaluation and planning project involved the establishment of a borehole data base for the storage, retrieval and analysis of both strata and quality data. During the second phase a numeric block model of the coal deposit was created. Using this model reserve calculations were carried out by specifying the area with the aid of a digitizing tablet. The third phase involved the develop- ment of systems to simulate the dragline stripping operations including the rehandle percentage calculation, a dragline production schedule showing coal quantity and quality exposed, and a combined multi dragline operation schedule that can produce figures and graphs for up to 20 variables. A derivative of the operating plan was a programme that gave productioh cost estimates

Jan 1, 1978

By Rospigliosi RT, Krouse HR

The San Vicente stratabound zinc-lead rhythmite deposit, Peru, is hosted in carbonates of the Late Triassic - Early Jurassic Pucara Group. These strata were deposited in a large, shallow water, carbonate platform which extended nearly continuously for 150 kilometers (north-south) in the eastern part of the Pucara basin.The distinctive sulfide-bearing rhythmites occur in three dolomite units which, from bottom to top, include the San Judas horizon with one sulfide-bearing manto; the San Vicente horizon with seven sulfide-bearing mantos including the main ore horizon; and the Alfonso horizon with three sulfide-bearing mantos. The dark gray sulfide-bearing dolostone layers range in thickness from a few millimeters to a few centimeters and contain variable amounts of carbonaceous material, pyrite, quartz, fine-grained sphalerite and galena. They are bordered on each side by selvages of yellow to red-brown coarse-grained sphalerite containing minor amounts of galena. Coarsely crystalline white or gray sparry dolomite is found between the coarse-grained sphalerite layers. Although commonly stratiform and uniform in thickness, the dark layers curve, "pinch out," coalesce, and form "islands" and "peninsulas."Mineral replacement textures, the paragenetic sequence, and presence of sparry dolomite, bitumen, intraformational breccias and isotope data support a hydrothermal replacement origin by metal-bearing solutions that deposited the ore and related minerals in space previously occupied by dolomite and evaporite minerals. The alignment of the Zn -Pb deposits, and at San Vicente the orientation of the mantos, the spatially and temporally associated igneous sills and the tourmaline-bearing sandstone support hydrothermal mineralization driven by a magmatic heat source in a tensional regime.

Jan 1, 1990

Arrow Energy NL has been operating a number of coal seam gas wells in the Darling Downs region of Queensland. At the time of writing this paper, the region is enduring an extended drought period. The local aquifers are depleting and have not been significantly recharged in over a decade. The local communities (both rural and townships) are struggling to obtain water. Currently, coal seam gas (CSG) operators (under licence) draw water from the coal seams as part of the gas production process and the majority of operators choose to evaporate this water, as it is characteristically brackish to saline in quality and as such must be contained. Although the water produced from one CSG operator is not sufficient to drought-proof the greater area of the Darling Downs, there is potential to supply smaller local areas and contribute to the sustainability of these communities. This paper outlines the work completed by Arrow and its local community partners on the Darling Downs to date, and discusses the application of the produced formation water for:stock watering in feedlots, as a feedstock for coal washing, as a potable water supply for Dalby, as an agricultural water supply for cotton farming, and use as a medium for growing salt-water fin fish.

Jan 1, 2006

By S Maritsa, E K. Chiwandika, S M. Masuka

The iron and steel industry is experiencing an increase in the use of iron and steel commodities within societies, decarbonisation pressures, depletion of high iron ore grades and high energy consumption. This necessitates scrap metal recycling, low-grade ore utilisation using the induction or electric arc furnace to achieve the global target of net zero CO2 emission. The available highquality scrap metal cannot sustain the steel industry but the world has unused hematite-goethite ores. It is the aim of this research that this resource be utilised using the induction furnace to sustain the steel industry in an environmentally friendly manner. Indurated pellets prepared from the hematite-goethite ore, 5 wt per cent limestone and 5 wt per cent coal addition were smelted in the induction furnace at 1350 ± 50°C with 25 mins holding time. The effects of basicity and carbon content were also investigated to optimise the smelting parameters. The results showed that the careful control of the basicity, and iron-to-carbon ratio maximised total metal recovery. The optimal basicity ratio was determined to be 1.3 and a carbon to iron ratio of 1.4 achieved a total metal recovery of 73 per cent. The metal recovery was closely related to the estimated slag melting temperature. The basicity ratio of 1.3 achieved the lowest slag melting temperature estimated to be around 1380°C based on the CaO-SiO2-Al2O3 phase diagram. The recovered metal had a comparable chemical composition and microstructure to that products from an ITmk3 furnace.

Jun 19, 2024

By S Maritsa, E K. Chiw, S M. Masuka, ika, T Chisahwira

The challenges facing the iron and steel industry on a global scale include depletion of resources, excessive energy consumption and CO2 emissions. The demand for iron products in Zimbabwe is increasing due to massive infrastructural development like the expansion and improvement of mines, transportation systems and water reticulation systems. In Zimbabwe, cast iron is mainly produced from recycling scrap metals. However, there is currently a shortage of scrap, which has resulted in the vandalism of state-owned properties such as bus terminals and railway wagons and lines. Nevertheless, Zimbabwe is rich in limonite ores, which are idle, and it is the aim of this research that this ore be effectively used to produce feed for the blast furnace. The Blast furnace is still the dominant route for producing cast iron where sintering and coking processes are the main routes for preparing the Blast furnace feed. Sintering limonite ore fines produce a product of poor grade because of the high value of loss on ignition that has a negative impact on Blast furnace efficiency. Furthermore, the sinter plant and the coke making plant are a source of huge environmental pollutants. Since low-grade Zimbabwean coal fines are also available in abundance, they were used in the preparation of the composite materials ensuring maximum utilisation of this resource. Results showed that the limonite ore-carbon composite pellets sample with the binary basicity ratio (CaO/SiO2) of about 0.27 and coal addition of 2.5 wt per cent achieved above the minimum physical quality requirements for pellet of drop number of at least 4, a dry compression strength greater than 2.2 kg/pellet and an indurated compression strength greater than 250 kg/pellet. Limestone was used as the binder avoiding the addition of more impurities from bentonite since the limonite ore has a high SiO2 content of about 8.78 wt per cent.

Sep 18, 2023

By Smith PE

The main components of face design are the power loader, face conveyor and powered support system and the interaction of these components determines the effectiveness of strata control. A major influence upon the interrelationship of this equipment is the geological environment, of which seam thickness appears to play an important role. Recent thick seam experience indicates a significantly different characteristic behaviour pattern from that observed in thin seams The structural integrity of the face wall is particularly influenced by seam discontinuities such as natural joint planes and mining-induced fractures in the yield zone ahead of the faceline. In addition, the presence of stone bands or dirt partings in the seam offers interfaces for uncontrolled release of blocky material. Some case study experience at British collieries provides a comparison with performance data at a specific location, that highlights the importance of coal face layout and design.

Jan 1, 1986

Ulan Coal Mines Limited operates an underground and open cut mine near Mudgee in the Central West of NSW. The mines are part of a Joint Venture managed by Exxon Coal and Minerals Australia Limited (ECMAL). Currently all the mines output of over five million tonnes per annum is sold into the export market predominantly as a steaming product.

Jan 1, 1993

The demands of the economy require larger manufacturing facilities using greater quantit- ies of raw materials which must be mined, handl- ed, stockpiled and recovered with efficiency and dependability. All over the world, mining com- panies, steel manufacturers, power stations and process plants are not only seeking but finding methods of increasing outputs and'reducing costs in the field of materials handling. In mining bigger continuous mining machines and shovels, larger trucks and crushers are digging and processing greater quantities of differing materials which have to be handled and shipped at rates once thought to be impossible. To implement such schemes demands the blending of a lot of diverse-equipment, mining machinery, bins, feeders, reclaimers and it is here that the belt conveyor assumes a role of ever increas- ing importance. Significant developments have taken place in the seventies with respect to conveyor belt transportation; not only in the systems but also in the components which combine to make such systems work efficiently.

Jan 1, 1976

By C Mark, Z Agioutantis

This paper presents an empirical design methodology that is based on successful US roof support systems using both primary and secondary support in coal mining entries and intersections. The recent nationwide dramatic reduction of roof fall rates, especially in areas with weaker roof, can be directly correlated to the effectiveness of the roof support systems. A large database of roof fall histories at several mines is used to define the approximate boundaries of three modes of roof support with respect to roof strength as classified by the Coal Mine Roof Rating (CMRR) and in situ vertical stress as indicated by the depth of cover. These roof support classifications are: • Suspension, where roof bolts mainly provide skin control for strong roof. • Beam building or reinforcement, where a roof of moderate strength can be supported by roof bolts only. • Supplemental (secondary) support, where the primary support by roof bolts may be augmented by several secondary support systems, eg cable bolts, trusses, additional roof bolts or standing supports. The Primary Support Rating index (PSUP) captures the capacity of the primary roof bolt system as a function of the actually implemented roof control plan, ie roof bolt length, roof bolt density, and roof bolt capacity, while it does not consider the type of bolt. The actual PSUP value is compared against a suggested PSUP value derived from statistical analysis of US case histories. Where secondary support is indicated, the expected rock load determines the necessary capacity of the secondary support system. A new (free) software package, Analysis of Mine Roof Support (AMRS), implements the design methodology and also allows comparison with other international indices such as the Reinforcement Density Index (RDI), the PRSUP, etc.

Nov 29, 2022

By Dolan P

Various operating practices have been developed over many years to ensure safe and efficient production from the 1100 orebody. Some of these practices are described.

Jan 1, 1982

By W Curlewis, D Hake, Z Cuthbert

The South Island Line (East) will be a medium-capacity railway covering approximately 7 km from Admiralty Station to South Horizons Station on the south side of Aberdeen Harbour in Hong Kong, with intermediate stations at Ocean Park, Wong Chuk Hang and Lei Tung.South Island Line (East) Contract 904 project is located on the island of Ap Lei Chau at the southern side of Hong Kong island and requires extensive construction works to be completed in close proximity to the existing residential estates of South Horizons and Lei Tung. The project also has areas of significant cultural heritage, including 18th and 19th century temples and historical gravesites. Owing to the site access constraints and location for the project, detailed planning and methodology innovations have been required to ensure the most effective and responsible means of delivering the project works. To excavate the tunnels using drill-and-blast techniques in these restricted locations, the maximum instantaneous charge weight that could be fired while blasting was severely limited. To overcome these restrictions, the project team developed and pioneered the use of ‘deck loading’ in Hong Kong to minimise the impact of blasting operations and has successfully implemented double- and triple-deck blasting operations during the completion of tunnel excavation works.Upon completion of the drill-and-blast excavation, the tunnel lining works were completed using both in situ concrete lining with travelling forms and permanent shotcrete works.CITATION:Curlewis, W, Cuthbert, Z and Hake, D, 2014. SIL904 Hong Kong – Drill and Blast Tunnels, station blasting innovations (double- and triple-deck blasting) and lining solutions, in Proceedings 15th Australasian Tunnelling Conference 2014 , pp 21–28 (The Australasian Institute of Mining and Metallurgy: Melbourne).

Sep 17, 2014

The evolution of Hall process alumina reduction technology is des- cribed with particular attention to the pot lines. Future directions of tech- nological change are considered. It is predicted that the Hall process will continue to be the avenue for aluminium production for some time to come.

Jan 1, 1982

As this district is so far distant from the other mining centres and its mode of approach so circuitous, I am afraid that many residents of other portions of the Commonwealth never think of paying this" Australia's Silver City" a visit, to learn personally the many and various lessons everywhere available, and to become familiar with the really wonderful and interesting features and deposits (which pature has so lavishly bestowed in the mineralogical world) yet seemed to almost ignore or overlook when disposing of topogr,aphical beauties of landscape and vegetation) unless professional or business duties require their presence here. So it is to those whose life is necessarily spent in other parts of the States where they answer their call of duty, and yet feel an interest, either for business or other reasons, that my paper is specially addressed and prepared, and for that reason I witl endeavour to make my remarks more of an explanatory than a dictatorial nature. I feel sure that there. are many members of our Institute who are much more familiar, and have had many more years' experience in the various methods of timbering, filling, and ore extraction, etc., than myself, but I hope that over I6 years' experience in connection with mines and engineering works, the last six of which have been spent in Broken Hill, where, I have been very closely connected.

Jan 1, 1903

By G Love, S Maher

In Victoria’s onshore Gippsland Basin, geology is driving brown coal developments, and geologists are key decision-makers. Prompted by volatile energy prices and the likelihood of a carbon constrained future, significant work has been carried out on the next generation of technologies to be applied to this giant resource. These include new-generation gasification technologies, coal conversion processes yielding products as diverse as diesel and fertiliser, drying technologies producing thermal and metallurgical coals and in situ conversion processes. However, coals aren’t coals, and brown coal available for new projects will have different quality parameters and mining economics from that currently mined.New projects are likely to be developed on coals with moisture contents averaging 60 per cent and corresponding low energy values. Whilst ash values will be low, averaging just 5 per cent (dry basis), this will at times approach 10 per cent, which is a level that would challenge the installed-generation technologies. Sulfur values will average 0.4 per cent (dry basis), but at times exceed 0.6 per cent, requiring technologies that address the potential for sulfur dioxide emissions. Whilst localised high levels of the fluxes iron (>1 per cent dry basis) and sodium (>0.3 per cent dry basis) would increase fouling of installed technologies, they may be suitable for selected next-generation technologies.Project viability for this next generation of technologies will be strongly influenced by mining cost, and geologists are playing a role in identifying higher-value coal. At its simplest, this is being achieved for open cut mines through regional, vertical strip ratio assessments, which are considered a first-order proxy for mining cost. Follow up assessments are incorporating mining and processing cost, coal quality penalties and product revenues. At a regional scale, it is informing the likely location and relative timing of future mine developments, as well as thinking around rehabilitation strategies, infrastructure and land-use planning.For deeper coal, factors like macro permeability, the ability to isolate seams from aquifers, groundwater chemistry, pressure temperature conditions, connection with groundwater recharge and in situ biota are being used as vectors to in situ coal conversion opportunities.Matching coal to the next generation of technologies has benefited from regional-scale geological studies of coal quality and mining economics, and has benefited from early engagement between geologists, technology developers and project proponents.CITATION:Maher, S and Love, G, 2014. Matching brown coal to the next generation of Latrobe Valley projects, in Proceedings Ninth International Mining Geology Conference 2014 , pp 77–84 (The Australasian Institute of Mining and Metallurgy: Melbourne).

Aug 18, 2014

By Anderson K

In 1991, the first horizontal raise drill hole in Australia was successfully completed by Australian Raise Drilling Pty Ltd (ARD) at the Perseverance nickel mine of Western Mining Corporation's (WMC's) Leinster Nickel Operations in Western Australia. At that time, WMC were experiencing considerable difficulties in developing the horizontal drill drives through the orebody using conventional drill and blast techniques. Following the success of the initial hole, a further two holes were drilled as part of the evaluation program. The technique has proved so successful that it has been accepted by WMC for on-going development of drill drives at Perseverance.This paper describes the program. It relates how the project evolved, the modifications that were required to the equipment used, the performance experienced during the program and the future of the method in this and other applications.

Jan 1, 1993