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By Thomas R. J

Following asmallnumberofpollutionincidents involving the death of cattle from ingestion of cyanide that had escaped from gold processing plants, the Queensland Government undertook to develop competent guidelines addressing this problem. These guidelines, "Queensland Government Guidelines on Prevention of Water Pollution from Cyanide Use in Gold Ore Processing", issued by the Department of Environment and Heritage, Department of Resource Industries and Water Resources Commission, cover hydrology and general house-keeping intended to reduce the likelihood of significant impact from a spill or unintentional dis- charge of contaminated material. There are three major advances for Queensland embodied in this Guideline: ò the use of a design approach that gives site specific standards rather than trying to give a multitude of standards broad enough to cover all situations, ò the use of hazard assessment and a "critical period" hydrologi- cal design technique, and ò new monitoring and reporting requirements. The guideline is presented here in a summary form:

Jan 1, 1991

By H J. J Boshoff, A J. Karrasch

Mine planners frequently face the challenge of mitigating the impact of climatic events on mining operations, such as floods and droughts. Specific water management infrastructure can be implemented to meet operational requirements in response to these events. However, the effect of flood protection, for instance, may reduce the resilience of the site to drought. The probability and duration of unfavourable climate sequences significantly influences the net present value (NPV) of implementing specific water management infrastructure.Good life-of-mine planning will consider the incremental development of the project, and provide staged development plans. Water management infrastructure and the timing of implementation are facets of this process.CITATION:Boshoff, H J J and Karrasch, A J, 2016. A decision-making framework for water supply and flood protection options in net present value terms, in Proceedings Life-of-Mine 2016 Conference , pp 196–199 (The Australasian Institute of Mining and Metallurgy: Melbourne).

Jun 28, 2016

By Hungerford F

Long-hole drilling technology has rapidly advanced this decade beginning with rotary drilling/pump down camera surveying and culminating in down-hole motor drilling with cableless electronic surveying over the past two years. With the latter system, a high level of directional control is achievable in boreholes up to 1000m long. Past long-hole drilling across the industry has seen a mixture of success and failure. With these experiences, new and improved techniques and equipment have evolved. A number of long-hole drilling options are available as variations on the basic rotary and down-hole motor methods. They involve different levels of cost and equipment and vary in their suitability in different geological environments and definition of targets. Long-hole drilling is mainly target applied, either in defining geological structures in greater detail, or proving important mining areas such as longwall blocks, to be free of structures. Successful drilling hinges on a combination of drilling expertise, quality and appropriateness of equipment, understanding of geological conditions and good colliery support. Drilling expertise forms part of sound interpretation through keeping relevant records, understanding the reasons for changes in drilling conditions and implementing specific tests such as coring. The final interpretation builds upon all other available geological information. There is still scope for research into improved techniques and equipment. The use of long boreholes for geophysical surveys has high potential.

Jan 1, 1988

By S Hughes

The smelting of concentrates and secondary materials has been subject to increasing challenges in recent years due to declining grades of feed materials, increasing impurity levels and ever more stringent environmental regulations. In addition there has been a growing focus on maximising the efficiency of energy usage and recovery of values. New opportunities have been created with rising metals prices and improved systems for the collection of secondary materials, giving rise to a need for more flexible process solutions.This paper focuses on a number of specific cases where a process solution has been developed using the Outotec« Ausmelt Process to meet particular feed material challenges and overcome limitations inherent when employing traditional pyrometallurgical processes.The first case involves the development and commercial implementation of a smelting process to recover values from zinc smelting residues typically deposited into dams as a waste product. The second case describes the application of the Ausmelt process for the smelting and converting of secondary copper feed materials, including e-waste. These materials contain a wide range of metals and plastics and need to be processed appropriately to maximise the recovery of values whilst avoiding environmental problems. The third case study covers the smelting of nickel concentrates containing elevated magnesia levels as well as nickel bearing catalysts with high alumina content, neither of which can be readily processed when employing traditional pyrometallurgical technologies. CITATION:Hughes, S, 2013. Pyrometallurgical process solutions for complex raw materials, in Proceedings MetPlant 2013 , pp 519-530 (The Australasian Institute of Mining and Metallurgy: Melbourne).

Jul 15, 2013

The Coal Corporation of New Zealand Ltd (CoalCorp) is the largest coal producer in New Zealand, with extensive properties in both the North and South Islands. CoalCorp's North Island operations are kilcmetres to the south of Auckland. opencasts, are located in the catchment wildlife, historical and scenic values. in this catchment is the single most mining operations. centred on Huntly, a town some 80 Five coal mines, four of which are of Lake Waahi, a lake with significant The discharges of mine lodgement water important environmental constraint on Throughout New Zealand the use of water is controlled by a statute called the Water and Soil Conservation Act 1967. All industrial water users are required to hold Water Rights, which are in effect licences to take, use, dam, divert or discharge water. Water Rights are obtained through a legally defined process and any potentially affected party has the per to object to their granting. A special tribunal hears the evidence for and against an application, and issues its decision, which is reviewable in a higher court on Appeal. Rights, if granted, are issued subject to conditions and, in the case of mining discharges, limits would be set on flaw rate, suspended solids concentrations, turbidity, pH and the concentrations of any potential toxicants. This paper presents a case study of an integrated, catchment wide water management plan for Lake Waahi, that was prepared by the author, and others while the author was in the employ of CoalCorp, and its predecessor, State Coal Mines. The author is grateful to CoalCorp for their permission to submit this paper.

Jan 1, 1988

By Thomas W

Due to record low tin prices and an uncompetitive position in world markets, the Renison tin mine has undergone three major phases of restructuring in the last three years. This has involved substantial job losses, almost all of which have been through voluntary retrenchments. Retrenchments took place in 1988, 1990 and 1991.The last phase of restructuring was the most dramatic, as many aspects of the operation of the mine were changed. New pay structures were introduced, and the miners' contract system was scrapped. Drastic pay cuts occurred in many areas, although the opportunity was also taken to increase pay at some of the lower levels where inequities existed. Work practices were changed, as was the management structure.

Jan 1, 1992

By Shuguang L, Jing S

Computer controlled truck dispatching systems is a newly-developed technical system in surface mines with shovel-truck technology. The real time dispatching criteria, as the core of optimal truck dispatching software, are analysed and a new criterion, complex dispatching criterion, is put forward. Dispatching criteria previously proposed include: 1. `Earliest Loading' (EL) - to assign a truck to the shovel at which the truck can be loaded earliest. 2. `Max Truck' (MT) - to assign a truck to the shovel at which the truck will have the shortest waiting time. 3. `Max Shovel' (MS) - to assign a truck to the shovel which has been waiting for the longest time. 4. `Minimum Saturation Degree' (MSD) - to assign a truck to the shovel at the branch where the truck flow saturation degree is minimum. 5. `Minimum Saturation Degree with Truck Cycle time consideration' (MSDTC) - as the MSD principle, with the truck travel cycle also considered. 6. `Fixed Dispatching' (FIX) - to assign trucks to fixed shovels. A system simulation model has been set up for truck dispatching system analysis. A few surface coal mines have been selected for case studies. Equipment waiting times and shift production of the system are obtained as the main outputs of the model. Simulation results show that each dispatching criterion has its own applicable range, no one can absolutely dominate the others. For example, when under-trucked, EL and MT criterion can obtain higher production than the MS criterion; when over-trucked, it is vice versa; while for MSD criteria, better results can be obtained no matter how the truck numbers fluctuate. From the view point of shovel output balance, large fluctuations occur for EL and MT criteria, while a good balance can be obtained for other criteria. In the light of dynamic change of mining system conditions, a single dispatching criterion is not necessarily reasonable. A complex dispatching criterion has been put forward to seek the complex optimum effect. Taking the advantage of each dispatching criteria, the dispatching result of a complex dispatching criterion dominates over individual dispatching criterion and a comprehensive optimum effect can be reached.

Jan 1, 1995

Although the diesel engine is normally considered a tried and proven power source, many new and exciting diesel design concepts are being evaluated in engine development laboratories around the world. Three such programs currently underway at Cummins Engine Company are discussed. The turbocompound engine converts into power exhaust heat energy which is normally wasted. It does this by incorporating after the turbocharger a low pressure gas turbine which is gear driven to the crankshaft. The adiabatic engine has no conventional cooling system. It converts into useful power most of the heat energy normally rejected to the coolant. The series boost turbocharged engine uses seperate low and high pressure turbochargers to increase engine output and improve transient performance. These design concepts make possible increases in diesel engine thermal efficiency from the current 33 to 38 per cent range to the 50 percent range.

Jan 1, 1982

The emerging discipline of ægeometallurgyÆ is not new but is becoming increasingly recognised as a discrete and high-value activity that reflects an ongoing commercial and cultural trend towards more effective mine site integration and optimisation. Geometallurgy involves a quantified and spatially constrained approach to ore characterisation in terms of relationships to critical processing performance. Industry recognition of the need for large-scale, integrated geometallurgical research is currently supporting a major new research initiative. The AMIRA International P843 æGeMIIIÆ project (geometallurgical mapping and mine modelling) is a cross discipline collaboration involving four major Australian research groups; CODES the ARC Centre of Excellence in Ore Deposits at the University of Tasmania, a world leader in economic geology-related research; the Julius Kruttschnitt Mineral Research Centre (JKMRC) at the University of Queensland, a world leader in mining and mineral processing research; the WH Bryan Mining Geology Research Centre (BRC) at the University of Queensland, which aims to be a world leader in mining geostatistics, operations research and optimisation in mine design and planning; and CSIRO Exploration and Mining in the area of automated core logging. The project is currently supported by 19 global mineral companies. The project aims to deliver fundamental knowledge, tools and methods for more effective approaches to geometallurgical definition of mineralogy, element deportment and texture that can be linked to mineral processing performance and efficiency at a range of scales. Outcomes are improved predictive indices of processing performance that can be embedded in resource block models to define processing domains, which can be exploited in mine planning and optimisation. To achieve these aims the project is involved in a range of technology developments that include more automated core logging technologies, new applications of automated microscopy and development of software-based texture analysis and categorisation techniques. Attributes derived from these measurement technologies are used to develop predictive processing models linked to new small-scale physical testing regimes.

Jan 1, 2009

By Royston D

Victoria has an extensive brown coal resource, 202,000 Mt, of which 43,300 Mt is regarded as readily recoverable. This brown coal is located principally in the Latrobe Valley as thick seams and is being extracted at low cost primarily to support base-load electrical power generation. The high moisture content of the coal is partially off-set in many applications by the high reactivity of the coal and the generally low levels of potential pollutants such as ash, sulphur and nitrogen in the coal. Large scale development of this brown coal resource began in the 1920's. In addition to electricity generation, it is used for briquette production, carbonisation of briquettes to char and was gasified for town gas supply to Melbourne (1956 - 1969). The BCLV coal to oil pilot plant at Morwell is a major new initiative in the use of Victorian brown coal. Many other new developments are in place and emerging in the utilization of low rank coals. Examples of these developments are, the large-scale gasification of lignites in the USA, and value-added products such as bulk chars, solid fuels, activated carbons and coal-water mixtures. The Government of Victoria has created the Coal Corporation of Victoria to promote current sales of briquettes and to encourage further new industrial developments based on the State's brown coal resources, in particular the Loy Yang coalfield. The Coal Corporation also has a vigorous product and process oriented research and development Programme.

Jan 1, 1987

By D Pepper

Despite the limited literature regarding the pressure filtration of mine tailings (compared to the large number of papers published each year on paste thickening of tailings) the number of mines dry stacking filtered tailings is approximately equal to the number of mines storing tailings in paste form. Main drivers for filtering tailings are: water recovery, future rehabilitation costs for tailings storage area and permitting requirements. In arid climates, the cost and scarcity of water justify the capital and operating costs associated with pressure filters. Further justification for filtered tailings is the potential for progressive reclamation of the dry stack, which can proceed earlier and faster than the reclamation of a tailings dam.Filtered tailings must be transported to the storage area by trucks or conveyors. For dry stacking, 70 - 80 per cent solids content (by mass) is typically acceptable, however the primary goal is to provide a filter cake that is consolidated and dry enough to prevent bridging and build-up on the materials handling equipment. It has been observed that high average solids contents (~70 per cent) can be achieved while the centre of the filter cakes is still wet and sticky, presenting challenges for the transportation of the solids. Appropriate controls must be in place to ensure consistently easy to handle solids are discharged from the filter.FLSmidth has installed two fine coal tailings dewatering systems in the United States. One of these systems incorporates a Deep Cone Thickener« upstream of the filter press to minimise the amount of water that must be filtered, while the other tailings filter press is fed by a high rate thickener. The operation and performance of these filters is discussed and compared to the lab testing used to size the full-scale equipment.CITATION:Pepper, D, 2012. Operation of filter presses for tailings dewatering, in Proceedings 11th AusIMM Mill OperatorsÆ Conference, pp 241-246 (The Australasian Institute of Mining and Metallurgy: Melbourne).

Oct 29, 2012

I am honoured to be given the opportunity to share with you my thoughts on what will be the essential characteristics of æThe Mining Company for the 21st CenturyÆ. For me the 21st century is all about globalisation and the challenges and the opportunities that globalisation presents for the mining industry. To play on the global stage the successful mining companies must develop profiles that are global in: their operations diversity, their partnership relationships diversity, their customer relationships diversity, their workforce diversity, and their shareholder diversity. In my view æbigÆ will count in the 21st century, but big overlaid with quality: quality assets, quality people, quality partners, quality customer relationships, and quality image and reputation. Last year, Rio TintoÆs Leon Davis said when he addressed the Minerals Council of AustraliaÆs annual conference that Australian resource companies that wish to become global operators must develop an unequivocal international identity that will make that company a known and trusted quality wherever it seeks to do business. He went on to say that structuring and operating a business in a way that consistently manifests the qualities that inspire respect and evoke confidence is vital. I absolutely concur with what Leon said. Unfortunately, the fact is that, as we stand at the beginning of the 21st century, our industry and many of our companies are no better accepted by the world community than was the case five, ten, 15 or even 20 years ago. In fact, in some cases, the warmth of the acceptance may have subsided. To some extent the demonstrations that we saw recently in Seattle and Davos reflect a growing distrust, disquiet and cynicism in our communities. Here, however, I see an opportunity. While on the one hand the mood of disquiet presents many challenges, it also provides those of us who are willing to get out on the front foot in addressing the issues, and engaging in the dialogue, with a very significant opportunity to create a major competitive advantage. It provides the opportunity to earn respect and the opportunity to develop a reputation as a company that is sought as a joint venture partner and a company that is welcomed by governments and communities. Importantly, also, people will seek employment with such a company and will invest in such a company. The challenge is to change the way we behave and the way we are perceived by all the key stakeholders. Many of our industryÆs traditional skills are now commodities à many can be à and are out-sourced. The new critical skill for the 21st century à the real competitive advantage à will come from creating a real and genuine understanding of our role and what we stand for. Everything we do should demonstrate not only sound business principles, but also an understanding of the political, social, cultural and environmental impacts of our activities - at an international and a local level. This concept isnÆt new - but for large companies such as BHP, where we operate in more than 20 countries with diverse cultures, languages and religions - it requires enormous energy and dedication. It is complex. It is difficult. But I believe it is absolutely fundamental to our future.

Jan 1, 2000

The commercial outcomes from new mining projects or brownfields expansions often fall short of feasibility study forecasts because of technical under-performance. This paper: reviews past feasibility study performance; identifies the key drivers of underperformance; and proposes actions that can be taken to manage the risk of underperformance. There have been a number of published reviews of feasibility study performance since the 1970s. The results of these studies are summarised together with recent unpublished data. Key drivers of underperformance include inadequate metallurgical testing, simultaneously pushing a number of project parameters beyond comfortable limits and a failure to recognise the linkage between mining rate and head grade. Actions can be taken during the data acquisition phase and during the feasibility study to manage project technical risks. These generally require a more flexible approach to study management than can be achieved under a ælump sumÆ contract.

Jan 1, 2003

By A Maurer, N Pereira

Low-density explosives have been developed with trials being conducted for over 20 years and yet have still only gained limited market acceptance despite producing some very promising results. The biggest concern with industry acceptance has been disbelief that a product with lower density than the ANFO benchmark could fragment anything but the weakest of strata. Trials have been carried out with products such as diluted ANFO, low-density ammonium nitrate (AN) and various other mixes, although it has been only recently that low-density explosives have been accepted as a serious alternative to traditional products such as ANFO and heavy ANFO. The recent uptake of low-density products has been the result of several key factors: the current resources boom forcing AN supply issues, the development of new handling techniques, and a far better understanding of the utilisation of such products. This paper highlights the benefits of low-density products available in the market and focuses on the situations where low-density explosives can provide the end user with benefits that would otherwise be achieved through more time consuming methods. Through correct implementation, low-density explosives can provide the blast designer with another option when looking at the optimum method of breaking the rock. This while still controlling the other limiting factors such as cost, environmental impacts (noise, vibration, dust and fumes), coal damage and safety (stable walls).

Jan 1, 2005

The Australian mining industry can expect to be working internationally competitive high quality coal mines during the twenty-first century. Cost efficient mining methods such as high productivity longwall units with heavy reliance on remote control will be standard and worked by well paid and intensively trained operators. Major changes in mine ventilation engineering can be expected in the use of computers and mine telemetry, the understanding of the mine environment and the frequency of mine disasters, the utilization of mine air contaminants for profitable purposes and the provision of a pleasant and comfortable work environment. New approaches to mine ventilation such as air recirculation will have been considered. There will be an increased need for highly trained ventilation engineers. With the present pace of technological change, quite revolutionary new approaches to mining and ventilation can be expected by the end of the twenty-first century.

Jan 1, 1988

By M Boyd

The University of Wollongong was named University of the Year 2000, for its work in preparing students for the e-world. Computer facilitated learning is being introduced into subjects throughout the engineering course. First year mining engineering students are introduced to computers, e-communication, using the UniversityÆs web based information system, and web based subject delivery. Mining engineering students in the mid-years of the course use programming languages and numerical computation software such as MATLAB, while students in the final years use a range of commercially available professional engineering software such as TALPAC. Most of these subjects are offered as part of the UniversityÆs Learning Online program, co-ordinated by its Centre for Educational Development and Interactive Resources (CEDIR). Learning Online subjects are delivered using the Web Course Tools (WebCT) environment. WebCT allows all resources to be accessed through the web, allows email communication between lecturer and student, and allows discussion groups for the exchange of ideas. Students can submit their assignments through WebCT and receive immediate feedback. This paper describes how WebCT has been used to deliver a first year engineering computing subject, mid-year numerical computation subjects, a mining economics subject and mine planning subjects.

Jan 1, 2002

By A Grant, H Thomas, C Clarke, B Fuller

Native seed and plants are often a core input into the rehabilitation process of mine closure. Native plant establishment rate and performance is a function of many input elements including seed quality (purity and germination percentage), processing, treatment, storage, supply chain handling, application and ongoing management. Traditionally native seed has been supplied with very limited supporting information which in some cases has led to establishment failures, repeated attempts at successful plantings, and biosecurity issues, leading to increased rehabilitation costs for mining companies. Product procurement scrutiny, and sustainability credential requirements, in all supply chains is increasing the need for transparent, accurate, verified, and certified information. This collectively continues to evolve towards a social license to operate in all industries, including mining. The Australian Seeds Authority (ASA), in partnership with native seed supplier AustraHort, traceability software company Trust Provenance and supporting partners including Transport for NSW and Queensland Transport and Main Roads (TMR), were recipients of a DAWE National Traceability Grant. The project team has developed a framework and traceability software platform currently being piloted within the Australian native seed industry. The framework and platform allow for all critical-tracking-events along the journey of a native seed batch to be easily captured utilising a smart phone application (APP) and the global standard for data capture. The platform provides a unique identification for each batch of seed and critical tracking event. The batch ID belongs to that batch and all supply chain stakeholders can contribute to batch traceability by providing more information/data to increase information integrity. This gives the end user, and other stakeholders, increased levels of trust in the product to support value, increase efficiency and reduce costs. For mining companies these efficiencies and cost reductions are in the form of information availability across site/company, potentially improved vegetation establishment, less rework and efficient monitoring. Ultimately this contributes to safe, stable and sustainable rehabilitation. By capturing data on harvest, logistics, storage (including temperature and humidity), aggregation/blending, treatment, application and ongoing management, the native seed industry and end utilisers of native seed have a greater level of product integrity, brand integrity and information integrity.

Aug 2, 2023

By V Sahajwalla, S Shin

Research activities to classify the quality of iron oxides have a long history but most of such activities are for the existing processes such as blast furnace or DR plant. Therefore the newly developed process, such as the COREX process, needs new standardisation although some basic functions of the new process have similarity to the existing processes. Many researchers (Hauk, 1990; Cho et al, 1998) in the field of COREX process have conducted investigations since the early stages of the process development and activities are underway for further plant optimisation. As Agrawal and Oshnock (1995) pointed out, because coke is not included in the COREX reduction shaft the strength requirement of the feed materials in COREX process will be more demanding than that in the blast furnace. This condition is similar to Midrex DR plant but the main reduction gas of COREX plant is carbon monoxide generated from coal combustion while that of Midrex DR plant is hydrogen from natural gas.

Jan 1, 2000

By H Lehtonen, H Mansikkaviita

In primary copper smelters, the received copper concentrate and other materials contain a certain amount of moisture, ranging from six to 14 per cent. Moisture in wet concentrate has a negative effect on the performance of the smelting furnaces when it is fed directly to the furnaces, namely increasing the energy consumption and the off-gas flow. There are several drying technologies available for drying copper concentrate, varying from direct heated rotary dryers and flash dryers to indirect heated steam dryers. Application of steam dryers has changed the drying process for copper smelters. Produced from a waste heat boiler, steam as heating medium enables plant-wide heat utilisation. Fossil fuel used from outside sources to remove water is no longer required and the combustion chamber is not required. In addition special attention has been paid to overcome the known problems of pollution emissions, excessive wear, clogging and frequent maintenance. The Kumera steam dryer is featured with many advantages based on principal improvements in reducing tube element wear and increasing drying efficiency. Thus, it has been considered as the first choice for those smelters where steam is available.

Jan 1, 2006

Nickel laterite HPAL circuits are known for their complexity and have presented a large number of challenges to process engineers worldwide. An attitude commonly encountered by the author is that the beneficiation of the ore is relatively simple and that the difficult problems are in the realms of hydrometallurgy. On a number of occasions beneficiation has become the 'poor cousin' in the process design phase. Another common theme is that significant difficulties are encountered when beneficiation circuits are started up, invariably slowing the ramp-up of the remainder of the circuit. In some cases the problems impact on throughput for a long period and can require major rectification capital. The HPAL Ni laterite projects encountered each have their own set of beneficiation problems that need to be understood before an appropriate circuit can be designed. This paper will discuss a range of design issues including geometallurgy, ore characterisation through laboratory testing, the application of appropriate sizing and analytical procedures, the selection of appropriate unit operations, materials handling of plant feed and products and setting meaningful plant design requirements.

Jan 1, 2008