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By D Felipe, G J. Harbort

In the past 40 years substantial changes have occurred in flotation machines. This has included increases in mechanical cell size to 630 m3 , significant changes to flotation column aeration design and widespread use of the Jameson cell and other pneumatic flotation cells. Over the corresponding period there has been increased used of machine characterisation measurements to benchmark and optimise flotation circuit performance. JKTech maintains a database of industrial flotation machine characterisation measurements. The database contains over 4000 entries and includes gas dispersion measurements, such as bubble size, gas hold-up and superficial gas velocity, cell dimensions and impeller tip speeds. Data comes from numerous operating sites and commodity groups, including gold, copper, molybdenum, nickel, palladium, lead-zinc, platinum, silica, phosphate, coal and iron ore. Flotation duties registered include flash flotation, preflotation, roughing, scavenging and cleaner circuits. Measurements have been conducted on a wide range of flotation machines from different manufacturers. This includes forced air machines, such as Outotec and Dorr Oliver, and self-aerated machines, such as Denver and Wemco. The database also includes substantial flotation column entries, such as the Microcel, Eriez/CMT Slamjet and Jameson cell. This paper describes the flotation machine characterisation database and discusses the variation between different types of industrial flotation machines, in operating production circuits.

Aug 24, 2022

By P Moynagh

"A plan is critical but on its own it is a bit one dimensional, the three dimensions critical to success over the long-term, through changing economic, geological and management conditions are:the quality of your planning an ability to see and adapt to change a disciplined continual improvement/learning system.This paper will examine how a number of major Australian resource companies have used a commitment management system to connect the ‘theory’ embodied in plans (whether mine, project, maintenance or training plans) and immediate reality ‘practice’ as experienced by supervisors and their crews in the workplace. This paper draws on management theory embodied in management operating systems (MOS), Lean, Theory of Constraints and Six Sigma approaches to continuous improvement and a good dose of real world experience. It is embodied in the statement: ‘successful organisations are driven by a series of commitments that people make to each other and deliver on’.Citation:Moynagh, P, 2016. Everyone Has a Plan Until They Get Punched in the Mouth – Creating Trust, Commitment and Results in Tough Times, in Proceedings Ninth AusIMM Open Pit Operators' Conference 2016, pp 293–299 (The Australasian Institute of Mining and Metallurgy: Melbourne)."

Nov 15, 2016

By S Nkwanyana, I Govender

Batch experiments in a 0.6 m diameter mill have shown that improvements of about 13 per cent in the efficiency of energy utilisation can be realised in ball mills by replacing 25 per cent of the ball charge by an equivalent volume of cost-free critical size pebbles from AG/SAG mills. For a mill of a given size, speed and charge filling, the rate of size reduction of ore particles depends on (i) the frequency of grinding media collisions (ii) the probability of capture of ore particles between the colliding grinding media (iii) the probability of fracture of the captured particles. The probability of fracture depends on the magnitude of collision energy. The distribution of collision energy into shear and impact events determines the relative strengths of attrition breakage and impact breakage. The efficiency of energy utilisation depends on which of the two mechanisms of breakage is more desirable in a particular milling stage. In this paper collision data from a series of DEM simulations of a mill charged with steel media and a mixture of steel media and pebbles is presented in energy spectra and spatial distribution maps. The data provides the necessary detail to elucidate the improvements in the efficiency of energy utilisation in ball mills when using a mixture of pebbles and steel media.

Aug 24, 2022

By N Winkelmann

Underground coal heating is a significant hazard in some coal mines. The broad principles of how underground coal heatings occur is reasonably known, however the technique for locating the heatings in often inaccessible goaf has been proved to be difficult. Since 2002, CSIRO, with the support of the Australian Coal Association Research Program (ACARP) has been undertaking investigations to apply and develop innovative surface-based radon technique for locating the underground heatings in Australia. This paper presents the progress of the investigation.

Jan 1, 2005

The effectiveness of three different types of longwall chock under the three different types of geological conditions worked recently is outlined. Some provisional analyses of the variation of chock load under the shale roof con- dition are briefly discussed and some problems and solutions of gateway and road- head support outlined.

Jan 1, 1974

Beach sands on the Morobe coast of New Guinea contain significant amounts of chromite. This chromite, together with the more abundant associated minerals such as olivine, enstatite, tremolite, antigorite and feldspar has been de- rived from rocks of the Papuan Ultramafic Belt and transported to the beaches by three rivers, the Paiawa, the Saia and the Sesimbai. Of the hundreds of samples taken, 26 have been analysed mineralogically and chemically in some detail. On this basis, five groups of samples, four on- shore and one offshore, representing character- istic mineral assemblages, have been recognized. The chromite grains themselves have been exam- ined to determine variations in amount and in the Cr/Fe ratio, since this is of economic importance. Much of the chromite fails to reach a high Cr/Fe ratio as a result of magnetite rims around chromite grains. The precious metal content of the sands is negligible.

Jan 1, 1973

Many types of micro-organisms inhabit iron ore deposits contributing to biogenic formation and conversion of iron oxides and associated minerals. Bacteria such as Paenibacillus polymyxa are capable of significantly altering the surface chemical behaviour of iron ore minerals such as haematite, alumina, calcite and silica. Differing mineral surface affinities of bacterial cells and metabolic products such as proteins and polysaccharides can be utilised to induce their flotation or flocculation. Mineral-specific bioreagents such as proteins are generated when bacteria are grown in the presence of haematite, alumina, calcite and silica. Alumina-grown bacterial cells and proteins separated from such cells were found to be capable of separating alumina from haematite. Biodegradation of iron ore flotation collectors such as amines and oleates can be effectively utilised to achieve environmental control in iron ore processing mills.

Jan 1, 2009

By S Hanrahan, S McLaughlin

A case study is presented that details the safety journey at a North American project involving two major contracts: a 1000 m shaft recovery and rehabilitation, and the development of a drainage gallery in a large open pit operation. In the early stages of the contracts, there were a number of incidents that created tension between the owner and contractor, which resulted in the contractor being placed on a final warning with almost imminent potential termination. As a result of this, it was agreed to initiate a focused safety recovery plan as a ‘last chance’.Over a period of two years, the engagement and consequent performance of the contractor was turned around, steadily working to set it up for success such that in one of the contract work areas, a record of ‘one year LTI (lost time injury) free’ was achieved. The journey involved the owner and the contractor teams working cohesively to educate all parties in the safety requirements and, most importantly, providing the context and understanding for certain requirements being put in place. Early on in the process, it was recognised that the owner team unknowingly was an impediment in that they did not fully understand the safety requirements and so was not able to lead the way for the contractor effectively. The journey to rectify the situation was supported and followed up by focused engagement with the project team, which generated a progressive improvement in a very challenging environment.In particular, the contractor turnaround was significant and of enough value for the contractor to ultimately export some of the safety systems from this site to other contract sites. This demonstrated the ultimate benefit of the contractor understanding and buying into a safety culture and system.CITATION:Hanrahan, S and McLaughlin, S, 2016. Winning the safety battle, in Proceedings International Mine Management Conference, pp 181-186 (The Australasian Institute of Mining and Metallurgy: Melbourne).

Jun 22, 2016

By X Sun, L B. Zhou, H Yi, X Tang, P Ning

The rapid industrialisation in China has consumed large amounts of various industrial raw materials, which has left behind large quantities of industrial solid wastes produced from the processes of mining, mineral processing and smelting. The storage of huge quantities of industrial solid wastes is an obvious risk to the environment and human well-being. As the first step to fully appreciate the scale of this risk, it is necessary to carry out research for developing a pollution source environmental risk assessment system (PSERAS), especially for the typical staple industrial solid waste (TSISW). This paper aims to discuss the frame of the PSERAS for TSISW for large scale production. This system consists of two aspects: predicted factors and accidental ones, which involve physical, chemical and biological risk assessments, on-site and during transportation process. Two analysis methods, the analytic hierarchy process (AHP) and fuzzy logic assessment (FLA) were used to handle the complexity of environment and non-quantitative data. The risk assessment system for such a complex objective is difficult and the assessment of relative factors is problematic through the usual quantitative analysis. With the proposed PSERAS, it is possible to define the risk class of pollution sources. Furthermore, the risk assessment results will be helpful to the decision-maker, especially when facing unknown risks in the environmental management of industrial solid wastes. In addition, by means of the PSERAS, risk factors can be ranked against their contributions to environmental risk, in order to calculate their relative priorities in decision-making.CITATION:Sun, X, Ning, P, Tang, X, Yi, H and Zhou, L B, 2012. Environmental risk assessment system for typical staple industrial solid wastes, in Proceedings Life-of-Mine 2012 , pp 301-304 (The Australasian Institute of Mining and Metallurgy: Melbourne).

Jul 10, 2012

By D Walker, A Tsvetkov, P Voigt, O Kloiber-Deane

The GPM Gold Operation has been employing an Albion Process™ plant at its Sotk (Zod) gold mine in Armenia since 2014. Long term data from the operation is now being published for the first time. The data presented includes concentrate throughput, as feed to the Albion Process™ plant (tonnes per day), sulphur grade in concentrate (% S), total sulphide sulphur oxidation in the Albion Process™ plant (% SOx) and gold recovery from Albion Process™ plant residues (%). The data provides a basis for evaluation of the effectiveness of the commissioning, ramp up and operation of the Albion Process™ plant. Notwithstanding the impact of a slower concentrator commissioning than expected, the plant demonstrates Series 1 behaviour on McNulty ramp up curves, indicating successful commissioning and fast ramp up. Interrogation of the data and operational experience indicates that this successful operation is a result of a process that is flexible, robust and stable, one that was designed well based on solid testwork results and pilot plant trials during the study phase undertaken by Glencore Technology and Core Resources, and where the local operators were provided with appropriate training in operation of the plant. CITATION:Voigt, P, Walker, D, Kloiber-Deane, O and Tsvetkov, A, 2018. Ramp-up and long-term performance of the Albion Process™ plant at GeoProMining Gold Armenia, in Proceedings 14th AusIMM Mill Operators' Conference 2018, pp 339–350 (The Australasian Institute of Mining and Metallurgy: Melbourne).

Aug 29, 2018

By M J. Gillespie, P D. Erskine

Mine site rehabilitation generally includes the re-shaping of overburden to create a final landform, manipulation of substrates and subsequent revegetation. Due to the wide range of environmental variables that influence rehabilitation progression, having clearly-stated final land-use goals and ongoing significant contributions to the planning process, from prefeasibility through to mine closure, is essential for achieving stable landforms and sustainable rehabilitated communities. Two examples of rehabilitation processes in the phosphate rich region of North West Queensland are used to illustrate some of the possible benefits of early planning and communication of rehabilitation requirements.Approximately 160 km south of Mount Isa, Incitec Pivot Limited operates a 35 year old open cut mine at Phosphate Hill. Monitoring of rehabilitation areas and selected analogue sites is undertaken annually, but the initial landform design, substrate management and species selection has created a difficult environment for revegetated areas to successfully establish. Constant management input (such as weed management, erosion control, supplementary seeding, etc) will, therefore, be required over a long time frame.The second example uses exploratory drilling and historic costean pits at Legend International HoldingÆs Paradise South site, 135 km north of Mount Isa, to determine the success of natural vegetation colonisation on waste rock and compacted soils, and the effects of cattle grazing on recolonisation. This information can be used by planners of the mine life to inform possible end-land use decisions and proposed completion criteria.In a semi-arid environment such as North West Queensland, the creation of a post-mine landscape suitable for nature conservation and/or grazing can be an arduous task. The input from environmental personnel at all stages of the mining process will positively impact upon the quality of the resulting rehabilitation and ensure undesirable legacy issues are minimised.CITATION:Gillespie, M J and Erskine, P D, 2012. Importance of early rehabilitation planning - Case studies from North West Queensland, in Proceedings Life-of-Mine 2012 , pp 187-196 (The Australasian Institute of Mining and Metallurgy: Melbourne).

Jul 10, 2012

By M Nagarajan

Orica Mining Services (Orica) in partnership with Coal and Allied’s Hunter Valley Operations (HVO) has developed a risk management process to maximise mining efficiency whilst controlling vibration and maintaining critical electricity continuity to New South Wales (NSW) electricity grid in the Riverview Pit. The issue is a high tension tower which supplies electricity located within 40 m of mining and blasting activities. The process involved developing an understanding of the relationship between vibration, explosives, geology and the location of the blasting in the geological horizon. From this an optimum methodology for blasting in each region was developed.

Nov 8, 2011

Plant growth is likely to prove the most suitable and satisfactory material to stabilise and cover quarry faces and worked-out surface mining sites. The careful selection of plant species is of paramount importance to the success of any attempts to re- vegetate these sites. Various tech- niques are recommended and attention is drawn to different factors,which will adversely affect plant growth.

Jan 1, 1976

In the southern part of China, car-bonate rocks outcrop in large areas. Ka-rst develops owing to hot, humid climate and heavy rainfall. In deposits of coal, iron, bauxite, tungsten, tin and base metals exist karst formations within or near the mineralization zones. Three pro-blems should be solved in the mine cons-truction in karst region. The first is the drainage and safety control of karst groundwater. Different methods are used to cope with local hydrogeological con-ditions, e.g. drainage from surface by submersible pumps in wells penetrating groundwater seams; drainage from under-ground drifts which intercept groundwa-ter flow with clusters of holes drilled into karst aquifer or with vertical ho-les drilled from surface to the drift underground; cement grouting to block off channels or to seal a part of aqui-fer; groundwater pollution control; etc. With those measures many Chinese mines of tremendous waterflow were success-fully developed and valuable experiences were gained. The second problem is the stability of buildings deteriorated by surface subsidence due to drainage. The occurence and distribution of surface cavings by drainage were studied.

Jan 1, 1990

Government established and financed the NZ Steel Investigating Co in 1960. Its investigations showed that a steel industry was feasible and desirable based uponNorth Island titanomagnetite ironsands, and charted a route for its establishment. The initial processing used post-1945 preheating and prereduction developments, but later innovative improvements created what was essentially a new New Zealand technology. Of the North Island titanomagnetite deposits: the small ones at Waipipi were best made available for export; those at Kawhia and Taharoa were too remote for the economic siting of a mill; that at Raglan proved too small; while at Waikato North Head three times the requirement of 50 million tons of concentrate were located in two sand areas averaging 18 per cent titanomagnetite. Economic studies showed that a South Auckland site would be ideal, close to New Zealand's biggest market. The mill site, on a basalt flow at Glenbrook, was located by a half-day's fieldwork - near both the Waikato North Head deposit, and a railhead for bringing in Waikato coal, etc, and taking out steel products.   This development was one of several since World War II which altered significantly the lives and homes of New Zealanders (others were natural gas, oil, geothermal power, epithermal gold, aluminium, opencastable lignite, etc). All had the essential ingredients of the highest government backing, direct or indirect government finance, and first-class New Zealand scientific and engineering skills (eg to create new technologies). Not one such project failed.

Jan 1, 1993

By E J. Hancock, K H. B Chu

Failures within hard rock underground excavations have historically been defined by a depth of failure, estimated in the field or through individual measurements, with a simplified failure geometry; such as 1/3 span, cubic or paraboloid. This simplified shape, volume and mass of failure is typically used to estimate in situ demand as a simplified discrete point. However, the highly variable failure geometry indicates simplified methods to estimate the mass can be erroneous in comparison to high precision LiDAR scans. Advances in technology have enabled the accurate capture of failure geometry and allow a far more accurate analysis of failures to be completed. This case study investigates a number of real-life failures to accurately define the failure geometry, the distribution of the failure parameters and compares this to traditional methodologies. This paper also outlines a suggested means of standardising failure geometry parameters whilst accounting for their variability.

Nov 29, 2022

By Aziz N. I

Examination of the geology and support performance at two site leads to development of an under tanding of the influence of caving on powered support rating. The two site represent the current extremes in support rating, i.e. 6/260 tonne supports operating in the Hirst seam at Solsgirth Colliery, Scotland, and 4/900 tonne supports operating in the Bulli seam, West Cliff Colliery, Australia.A conceptual model considers the coal ahead of the face, the powered support, and the caved waste to be three yielding foundations which interact to control the subsidence of the roof strata.The caving mechanisms identified for the strata of the Hirst and Bulli seams, are different. These mechanisms being related to rock properties - the palaegeography and depositional conditions at each site-produce caved wastes with different yield characteristics.An analysis of the results obtained for convergence and support reaction during production cycles at both sites shows the manner in which support reaction is developed, indicating the importance of higher setting load densities in the Bulli seam.Evaluation of the work done on the subsiding roof strata during typical production cycles by two of the yielding foundations the powered support and the caved waste immediately behind the powered support - further demonstrates the influence of caving mechanisms on support rating.

Jan 1, 1989

By H Kurth, L Balzan

The potential for bulk diversion was identified and quickly implemented following the development of bulk sensing technologies applied to conveyed flows. In the early 1980s real time analysis of ash in coal was intended to improve the understanding and control of quality variability. By the end of the 1980s approximately 5% of coal analysers installed were being utilised for bulk sorting; diverting flows to create stockpiles to improve blending flexibility and boiler feed consistency, diverting waste material, or bypassing the beneficiation process when the coal met product quality criteria. In the 1990s bulk sensing and sorting utilising natural gamma detection was applied to conveyed waste in gold-uranium mineralisation and allowed ore to be recovered and processed that would otherwise have been discarded. Further applications developed in the iron ore sector where product quality ore could be diverted to bypass beneficiation and save significant unnecessary processing costs and improve recovery by avoiding process inefficiency losses. Plant capacity was freed up to be utilised by material that required processing. Similar benefits became evident in the phosphate industry and in base metals where multi-elemental analysis using Prompt Gamma Neutron Activation Analysis provides ideal opportunities to representatively measure 30 second conveyed increments at high accuracies. This has been successfully adopted in copper, nickel, platinum and lead-zinc to improve waste removal after primary crushing to eliminate unnecessary expense and improve plant efficiency. The benefits include increased output from existing operating capacity, significant reductions in consumable costs and generation of fewer detrimental waste streams. The paper outlines the technologies and discusses case studies covering the above commodities, demonstrating the immense value that representative real time measurement of conveyed flows can create. Measurement data concurrently provides multiple benefits in operational performance besides sorting, through ore reconciliation, ore blending, feedforward control and metal accounting, adding further value.

Nov 10, 2020

By M Goers, M Almond

"The use of reverse circulation (RC) drilling for grade control sample collection was selected by the Pueblo Viejo Mine Geology department at the recommencement of the operation in 2010. This method was selected because it allows: for multi-bench drilling (60 m hole depth, four benches of mining) to aid mine planning and provide a detailed close spaced drill data comparison with the reserve model angled drill holes to optimise the drill hole interception of the vertically controlled mineralisation dry sample collection in areas of excessive surface and groundwater mining operations to commence with the long assay return period (due to the need for the samples to be shipped overseas for analysis) until the on-site laboratory is operational.To date, 118 302 m of drilling has been completed throughout the operations of two open pits: Monte Negro and Moore. Two drill rigs (contractor and site-owned and operated) with three generations of sampling systems have been used to date. Throughout the drilling a 20 per cent quality assurance, quality control (QAQC) sample check (blanks, field duplicates and standards) have been used to check the drilling and laboratories performance. In addition, a total of 1104 fines samples were collected to compare the drill chip samples collected and the fines lost with two of the sample systems used.The drilling to date has highlighted the need for a complete and coordinated system to be used before sufficient confidence in the quality of the samples collected is achieved.The complete system must be set-up and coordinated to obtain the best quality sample possible. This complete package includes: drill bit size and shape for the rock being drilled and mineralisation targeted face sampling hammers with the correctly sized hammer shrouds sample hose routing to reduce sample flow turbulence and choking blow-down valves to eliminate drill hole water that has entered the drill string during rod changes correct drilling techniques targeting sample quality a sample system that captures the fines for inclusion into the sample.These improvements can be obtained without reducing the drilling rates.The measurements required to demonstrate the improvement in the sample quality will be the focus of future work within the department.CITATION:Goers, M and Almond, M, 2012. Bit to bag - The importance of a total coordinated system in reverse circulation drilling, in Proceedings Sampling 2012, pp 65-72 (The Australasian Institute of Mining and Metallurgy: Melbourne)."

Aug 21, 2012

By J Jeffery, P G. Knott, F Velge, C Evans

A trigger action response plan (TARP) provides a structured response to escalating levels of risk. In mining, TARPs are typically applied to primary hazards such as inrush, strata failure or heating. Necessary for the creation and deployment of a TARP is a monitoring system capable of detecting deviations from normal conditions. The advent of real-time instruments capable of measuring diesel particulate matter now permit decision-making within shifts to address possible overexposure. Deploying a TARP for diesel exhaust emissions can lower the probability of a person’s average exposure (over a full shift) exceeding the exposure standard by detecting deviations of diesel particulate concentrations from normal conditions. This enables pre-emptive action to mitigate or protect. Another goal is to drive ambient air concentrations lower through the application of corrective actions as a result of instances where concentrations exceed ‘normal’.CITATION:Knott, P G, Evans, C, Velge, F and Jeffery, J, 2015. Trigger action response plans for diesel exhaust exposures, in Proceedings The Australian Mine Ventilation Conference, pp 129–132 (The Australasian Institute of Mining and Metallurgy: Melbourne).

Aug 31, 2015