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By M W. N Buxton, M S. Shishvan, J Benndorf

The flow of information, and consequently the decision-making along the chain of mining from exploration to beneficiation, typically occurs in a discontinuous fashion over long timespans. In addition, due to the uncertain nature of the knowledge about deposits and the inherent spatial distribution of material characteristics, actual production performance in terms of produced ore grades and quantity and extraction process efficiency often deviate from expectations. Reconciliation exercises to adjust mineral reserve models and planning assumptions are performed with timely lags of weeks, months or even years.With the development of modern information and communication technology over the last decade, a flood of data about different aspects of the production process is available in a real-time manner. For example, sensor technology enables online characterisation of geochemical, mineralogical and physical material characteristics on conveyor belts or at working faces. The ability to utilise this additional information and feed it back into reserve block models and planning assumptions opens up new opportunities to continuously control the decisions made in production planning to increase resource recovery and process efficiency. This leads to a change in paradigm from a discontinuous method to near real-time reserve reconciliation and model updating, which calls for suitable modelling and optimisation methodologies to quantify prior knowledge in the reserve model, process and integrate information from different sensor sources, back propagate the gain in information into reserve models and efficiently optimise operational decisions in real-time.This paper introduces the concept of an integrated closed-loop framework for real-time reserve management, incorporating sensor-based material characterisation, geostatistical modelling under uncertainty, modern data assimilation methods for sequential model updating and mining system simulation and optimisation. The effectiveness of the framework and the value added will be demonstrated in an illustrative case study.CITATION:Benndorf, J, Buxton, M W N and Shishvan, M S, 2014. Sensor-based real-time resource model reconciliation for improved mine production control – a conceptual framework, in Proceedings Orebody Modelling and Strategic Mine Planning Symposium 2014, pp 223–234 (The Australasian Institute of Mining and Metallurgy: Melbourne).

Nov 24, 2014

By Denholm W. T

The SMELT-2 package is specifically designed to perform on-line simulation of smelting processes. This paper describes its application to the simulation of continuous matte converting followed by reductive slag cleaning in SIROSMELT reactors. The matte, containing 50% Cu is assumed to be produced at the rate of 20 tph in a continuous matte smelting furnace such as an Outokumpu Flash Furnace, Noranda or Sirosmelt reactor. Two alternative fluxing strategies in the converter are examined, namely: ò conventional silicate slags, ò calcium ferrite slags, and the flow sheets associated with each strategy are discussed. A regular solution model is used in the present study to account for the variations in the activity coefficients of components in the slag.

Jan 1, 1989

The basic flowsheet for the Kalgoorlie Nickel Smelter and Kwinana Nickel Refinery are discussed in relation to the mineral components of Kambalda produced nickel concentrates. Both processes handle violarite and pentlandite satisfactorily but the smelter has limitations where high copper recovery is required and in its ability to handle magnesia containing minerals. While the latter can be more economically handled at Kwinana the limitations of this tolerance are discussed together with problems arising from treating pyrrhotite, pyrite and precious metals by the Sherritt Gordon process.

Jan 1, 1973

This paper deals with innovative techniques that have enabled personal computers to be used on the mine site to define, develop and manage an ore body resource, while being aware of the consequences to the environment. The same set of personal computer tools that are used for resource estimation, once the province of expensive workstations, can also be used by geologists, mining engineers, surveyors and environmentalists, in managing the whole mining process, including production, grade control, monthly reconciliation and stockpile management through to tailings the management, mine rehabilitation and the due diligence process of mine closure.

Jan 1, 1996

By A T. Spathis, K E. Leslie, K R. Blay

Many open pit mining operations seek to control blasting-related movement of ore and waste to minimise loss and dilution. Tracking the movement of ore boundaries can result in the maximisation of ore recovery and minimisation of waste sent to the mill, thereby optimising the economic performance of the operation.A novel solution for tracking the ore–waste boundary location before and after a blast uses subsurface markers placed along the boundary with all measurements and scans conducted remotely from the blast block. Upon system activation, user-operated equipment on the surface determines the three-dimensional (3D) location of the subsurface markers.The patented system concept combines two electromagnetic mechanisms, magnetic positioning and radio frequency through-rock communications to enable remote battery-powered markers, buried within the rock to be accurately located in 3D space.Field trials at a quarry have demonstrated the system can comfortably handle over 100 subsurface markers with a complete scan, including set-up, taking less than an hour. Location accuracy for each marker in 3D space is better than 0.5 m at a range up to 50 m from the magnetic source, and the system has an overall operational range in excess of 75 m.CITATION:Blay, K R, Spathis, A T and Leslie, K E, 2015. A remote, rapid and accurate three-dimensional ore waste boundary tracking system, in Proceedings 11th International Symposium on Rock Fragmentation by Blasting, pp 297–306 (The Australasian Institute of Mining and Metallurgy: Melbourne).

Aug 24, 2015

By Hunter GW

This paper gives an account of the filling system at Mount Isa from surface fill production to stope discharge underground. A brief explanation of the surface facility and reticulation is given prior to the discussion on aspects of underground reticulation. These include fill hole types, pipe and breastplate installation, wear characteristics, etc. The different types of fill and their respective applications is mentioned as a prelude to a general overview of the mining considerations associated with fill placement and its role in the long term planning strategy at Isa Mine. Some practical aspects of stope preparation and filling procedures are outlined for the various stoping methods. Finally a brief outline of future fill developments is given.

Jan 1, 1982

By Chaves AP

This paper describes an investigation on the surface properties and mechanisms involved in the agglomeration of iron ore. For this purpose, an organic binder (carboxyl-methyl-cellulose (CMC)) was used in substitution of bentonite, the classic binder in iron ore concentrate agglomeration. Recently, a renewed interest of the iron ore producers in Brazil to replace bentonite for an organic binder, because of the economy that can be achieved in the, blast furnace operation. These savings are mainly due to the lower aluminum silicate addition which decreases slag volume and the improved pellet metallurgical properties which have the potential for lowering hot-metal production costs. Also organic binders are effective at lower addition levels, which results in lower storage and transportation costs. It is very important in Brazil because of the vast geographical area since transportation is made mainly by truck. Another advantage of organic binders is that they have low ash contents, and therefore most of the binders bum. off during the pellet firing operation. Previous studies have demonstrated the possibilities of the use of CIVIC, but in addition to its high cost, the pellets presented improper behavior at high temperatures or when prepared with high moisture levels. In the investigation here described, these problems have been solved through the addition of other reagents to CMC.

Jan 1, 1993

The equity market is now very much within a global village environ- ment, with various exchanges acting as agencies for the big casino. In this predicament, mining companies, who provide the most extensive, but relevant risk assessment information, will be best placed for favoured treatment by potential international investors: But what risk assessment information in summary form can be provided to support a resource/reserve statement? Even more importantly, does "objective" data exist, whose trends will support a resource/reserve state- ment? A prime need of the informed mining investor is to determine whether or not the resource/reserve statement is believable? But more importantly will it be realised? While the implications within the text of the majority of reports on resource/reserves suggests that the estimates are conservative, the record indicates that very few estimates are. In fact, to date, reports claiming to be conservative in respect of the overall grade estimate at a specfic cutoff have not reflected the realised grade at the stated cutoff; it has been more common for the realised grade to be lower than implied by the resource/reserve statement. Further, it is not uncommon for penalty elements to be understated and these components are rarely incorporated within resource/reserve statements.

Jan 1, 1988

By Amanatidis A

In this paper, the kinetics of iron precipitation as sodium jarosite from aqueous solution is investigated. The determination of the reaction mechanism is attempted based on the experimental data of iron removal as a function of time, without using the characteristics of the precipitate.Experiments at the temperature range from 50° to 95°C were carried out with initial conditions of iron concentration IQ g/L, sodium sulphate concentration 25.44 g/L, sulphuric acid concentration 3.68 g/L, pH = 1.5 and agitation rate 600 rpm. Temperature greatly and positively influences iron precipitation from the solution and this is accompanied by pH decrease. The activation energy was determined using the maximum values of the precipitation rate, which were evaluated by polynomial fitting of the sigmoidal shape experimental curves, and it was found to be 44.37 kcallmole. The determination of the rate-controll ing mechanism was based on some criteria used for the discrimination among the three probable mechanisms of precipitation (diffusion, mononuclear nucleation, polynuclear nucleation). These criteria utilise various funetions of the recovery 'a' of iron precipitated versus time, the most important of which are the chronomals. The results of the kinetic analysis procedure showed that the polynuclear nucleation growth mechanism controls the precipitation of iron as sodium jarosite. This was confirmed by the high value of activation energy, excluding diffusion as the controlling mechanism.

Jan 1, 1993

By Fejes A. J

The U.S. Bureau of Mines installed surface and subsurface instruments at a mine site in Colorado to monitor and characterize the overburden response to longwall mining. Instrumentation included a time-domain reflectometry (TDR) cable, a multiple-point borehole extensometer (MPBX), vertical- deformation surface monuments, and in-mine pressure cells for monitoring abutment, pillar, and gob loads with respect to the longwall face position. The purpose of the study was to collect data that could be analyzed to correlate the design of the mine layout to the resulting overburden failure response. Determining the extent of caving and fracturing is important in the and and semiarid Western United States because of the possible consequences to the fragile underground hydrologic systems upon which the land owners and users depend. This study is unique from past investigations because the overburden contains massive sandstone members that impose special conditions on the caving process and pressure redistribution above the longwall panels. This paper presents the results of this correlation study.

Jan 1, 1992

By Szymanski J, Planeta S

For many hard rock mines with near surface deposits, the surface crown pillars form the first line of protection for the immediate underground workings. Underground stopes are typically contained by crown pillar, which protects the level above, rib pillars, and a sill pillar through which the ore collection system is cut. This paper discusses the mining of these pillars, with particular emphasis on the overall stability of the mined out upper part of the mine areas. An area of interest is located in the Canadian Shield, where the mining has progressed below four thousand foot level in the ultramafic high grade sulphide type of orebody.

Jan 1, 1995

By Else D

While the underground mining work environment may have processes and equipment considered unique, most of the broad issues likely to affect the occupational health and safety of employees are not. One such occupational health and safety issue that is common to the mining sector and most other industries is noise. Noise as an occupational health and safety issue is of national significance. Presently noise induced hearing loss costs Australia around $35 million per year on compensation claims experience alone. Noisy equipment and work environments are still being tolerated in parts of the mining industry as `part of the job'. Where work has been undertaken in noise management, considerable emphasis has been placed on either industrial hygiene monitoring programs or the provision of hearing protectors to miners working on or around noisy equipment.Opportunities for more cost-effective and long term methods for controlling noise exist. Ready to apply solutions to noise problems in the mining industry are available, but for many mining operators this information is often difficult to obtain. To overcome this problem, the SHARE program collects and distributes solutions to occupational health and safety problems. The program aims to help organisations to close the gap between what is known about solving health and safety problems and what is actually being applied at the shop floor level: Recent developments have incorporated the SHARE program concept into worksite hazard management projects that involve the participation of employee representatives, front line supervisors and engineering personnel. Besides providing workforce members with an increased understanding of hazard management skills, the SHARE in-house program results in the implementation and sharing of solutions to health and safety problems by the program participants.

Jan 1, 1992

By S S. Kanchibotla, D La Rosa, R W. Pesch

The Porgera Joint Venture and Dyno Nobel have commissioned a joint project to optimise the drill and blast operations to increase the overall profitability of the mine. One of the aims of this project is to increase the throughput of semi autogenous (SAG) mills by optimising the blast fragmentation. A number of test blasts were conducted during the period May 2000 to January 2002 and the ore from these blasts was campaigned through the mill. The data from these trials suggested up to 15 per cent increase in the SAG mill throughput with high energy blast designs. However, changes in ore geology (shape, structure and hardness) and potential ore dilution/loss and wall damage have raised concerns about the economic benefits of these designs over the entire orebody. The lack of a system to track the economic benefits of these modified designs has also compounded these concerns. PJV and DynoConsult, the consulting arm of Dyno Nobel have initiated steps to minimise the potential for ore dilution and wall damage resulting from these modified designs. DynoConsult worked with Julius Kruttschnitt Mineral Research Centre (JKMRC) to develop and implement a blast management system to track the quality of blast implementation and down stream process benefits. This paper discusses the implementation of the system and the results achieved to date.

Jan 1, 2003

By Weller K. R, Stewart P. S B, Restarick C. J

The performance of the Renison tin concentrator was assessed in detail for two arrangements of the three available ball mills. With two mills used for primary grinding and the third for regrinding table tailing, the concentrator recovered 65.3 per cent of tin in the three tin concentrates produced by tabling, vanning and flotation at a calculated overall grade of 37.5 per cent tin prior to batch dressing. In the second arrangement one mill was used for primary grinding and two mills for separate regrinding of table tailing and sulphide concentrate. The metallurgical effective- ness of the change was somewhat obscured by unintended changes,i.e. an increase in the assay of the fresh feed from 1.38 per cent to 1.1+6 per cent tin and unresolved changes in the sulphide rougher flotation and tabling. However, using the results from a detailed size by size analysis of the behaviour of ore components in appropriate parts of the plant, it proved possible to show that, had the two unintended changes not occurred, up to 5 per cent

Jan 1, 1977

Data logged on mineral beneficiation processes during normal operation are analysed using time series (correlation and spectral) methods to identify the dynamics of the processes for on-line computer control. Recursive least squares estimation techniques are used to identify parametric models for a cassiterite flotation circuit and a coal washery. Identification problems such as the determination of model order, process time delays and the 'contamination' of the data by process recycle streams (feedback) are discussed. Typical results are presented in which optimised models are identified from data logged during normal operation.

Jan 1, 1985

By Johnson N. W, Quast K. B

Over the years there have been occasional references in the literature to the activating effect of cyanide in galena flotation with xanthates. These have usually been associated with the processing of lead-zinc or copper-lead-zinc ores. Bubble contact curves for the pure galena-xanthate system show a flotation edge at pH 10.4 independent of sodium cyanide concentration which was thought due to hydroxyl ion, not cyanide ion.Flotation tests were conducted on samples of Mount Isa lead-zinc ore using varying concentrations of sodium ethyl xanthate and sodium cyanide. At low collector concentrations, galena recovery kinetics improved with sodium cyanide addition, and the higher the cyanide concentration, the higher the galena recovery rate. At higher collector concentrations, galena recovery rate was independent of sodium cyanide addition.For a given collector addition, the lead grade-recovery curve shifted to an improved position with increasing sodium cyanide level. For the same recovery there was an increase in the lead grade with increased sodium cyanide addition, and this increase was most dramatic at high sodium cyanide concentrations.The presence of sodium cyanide during the grinding of Mount Isa ore caused surface passivation of the iron sulphides and possibly the sphalerite.These sulphides, therefore, reacted with less of the oxygen present in the pulp, hence more oxygen was directed to the surface of the galena. This resulted in an enhancement in the total amount of xanthate adsorbed on the galena that is reflected in the improved flotation response of that mineral.

Jan 1, 1990

By A G. Grice

Surface disposal of mining processing wastes is usually perceived as an undesirable consequence of meeting societyÆs needs for metals and minerals. Environmental disasters associated with the discharge or storage of such wastes, though infrequent, can have very damaging consequences for the environment and the industry. Reducing or eliminating the potential for such events may be achieved by placing some or all of these processing wastes back into the voids created by the mining operations. Processing operations may limit or enhance the opportunities for using tailings and other waste products as a backfill material. Backfilling is a truly multi-disciplinary process and requires the informed involvement of mining, metallurgical, engineering and environmental specialists. This paper describes the range of fill types currently being used in Australian mines, particularly those utilising processing wastes as constituents. It focuses on how processing operations can affect the suitability of these materials for the various types of fill, the resulting fill properties, fill performance and costs.

Jan 1, 2002

By Duncan GR

Having passed through a number of previous phases the best longwall results in Australia have shown a significant increase in the last two years. The results expected from a longwall face can be estimated from the ideal production rate, determined by the capacity of the equipment and the conditions in which it is installed, the utilisation, and the available operating hours. Back analysis of the results achieved suggests that, on average, recent improvements arise from the higher capacity equipment recently installed; the utilisation has in fact reduced slightly. Review of the constraints which limit the longwall results, i.e. shearer speed, AFC capacity, support, advance rate, and man travel speed, shows that little improvement can be expected in the ideal production rate in thinner seams. In thicker seams the AFC often proves the overriding constraint and further increase in equipment size could lead to increased future ideal production rates and is expected. In all cases a concerted effort to increase the utilisation achieved is likely. For deep mines with thin to medium seams this offers the most viable path to improvement; by contrast thick seams with highwall/shallow access may benefit from further increase in equipment size.

Jan 1, 1988

By Redman P. G, McMahon B. K

A simple technique for evaluating the field stress ratio is presented, based on the results of extensometer or convergence tape measure- ments taken in an advancing tunnel. This tech- nique also yields a value for the rock mass modulus, provided Poisson's Ratio is assumed. The results of two case studies are presented illustrating the effectiveness of the method.

Jan 1, 1981

By C M. MacRae

The characterisation of high-P iron ores by field emission gun electron probe microanalyser (FEGEPMA) was carried out to determine elemental associations in iron oxides sensus lato and, using this knowledge, to speculate on possible P incorporation mechanisms in goethite. Quantitative data was collected from two goethite-rich bulk ores and results showed that in both samples goethite was the main repository for phosphorus. The P-rich goethite also contained elevated levels of both aluminium and silicon.To understand the mechanism of P incorporation in goethite, high-P grains were located by coarse mapping of polished blocks with the FEG-EPMA. Analysis of element distribution maps collected on the P-rich grains showed that low-P regions within grains were typically associated with low-Al and high-Si, whereas high-P regions were associated with high-Al and low-Si. Based on follow-up quantitative analyses, a coupled substitution mechanism for phosphorus incorporation within goethite was proposed: 2Si4+ = 1P5+ + 1Al3+. Additional quantitative analyses on further examples indicated the mechanism was only valid for Si contents in goethite of <1 wt per cent.Preliminary transmission electron microscope (TEM) studies confirmed the presence of P, Al and Si in goethite.

Jul 11, 2011