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Many persons hold the opinion that the metal indus- ries are fortuitous and that the occupation is one of sordid toil, and altogether a kind of business requir- ing not so much skill as labour. But as for myself, when I reflect carefully upon its special points one by one, it appears to be far otherwise. So wrote Georgius Agricola in 1556. He could have been espousing the sentiments of an indus- trial archaeologist investigating mining sites in 1986. South Australia has a very rich legacy from its industrial past-especially in the area of its mining history. Industrial archaeology, which is part of the broad field of archaeology, is concerned with the material and documentary remains of this industrial past. This includes the products and processes of manufacturing, industrial, technolog- ical and engineering activity and their relation- ships to people and the environment. `Archaeology' immediately conjures up the image of excavations in Greece or Eygpt. Excavation however is only a part of archaeological methodology. Industrial archaeology utilizes documentary historical rec- ords combined with field survey techniques (both above and below ground) to create a composite picture of the past. Interest in our recent past has burgeoned in Australia in the last few years. This interest manifests itself in many ways-the unprecedented popularity of Australiana and col- lecting, the plethora of Australian historic films, the growth of the National Trust, local historical societies and genealogical research. Fortunately these trends have been reflected in academic and legislative circles. Various univers- ities, institutes of technology and colleges of advanced education run courses in aspects of cul- tural resource management and conservation of the historic environment. These courses are com- prised of archaeology, architecture, geography, his- tory, materials conservation, museum studies, and national parks management and planning.

Jan 1, 1987

By B B. Beamish

Long-hole directional drilling for in-seam exploration was introduced to New Zealand at Huntly West Mine in 1989. Following the success of this initial drilling program the Coal Corporation of New Zealand (CoaICorp) purchased its own drilling equipment and proceeded to adopt the technique with in-housetraining. From July 1991 to September 1992 a total of 15 455 metres was drilled at Huntly West Mine. During this period several modifications were made to the drilling technology to suit the ground conditions. The resulting interpretations of the drill information enabled reliable seam definition to be incorporated in mine planning. Since January 1993, the technique has been transferred to the Huntly East Mine to assist with seam definition for the planned development westwards under the Waikato River. The benefits of this drilling technique to coal mine planning are now well documented in Australia and New Zealand as well as other overseas countries. The possibilities of adapting the long-hole drilling technique to hard rock applications has been illustrated recently with successful cross-measure drilling at Huntly East Mine.

Jan 1, 1993

By A Saghafi, S Day

The control of spontaneous combustion in spoil piles is an area of concern for a number of open cut coal mines. Spontaneous combustion in spoil may occur when carbonaceous waste materials are exposed to air. In large piles, the relatively high voidage within the pile may allow sufficient movement of air through the pile to sustain oxidation and heat generation. Over the past decade, ACARP and CSIRO have funded a number of projects aimed at providing a better understanding of the causes of spontaneous combustion in spoil piles and the development of control strategies. Work has focused on prevention measures but has also considered measures available to deal with well-developed fires. Field, laboratory and numerical modelling methods have been brought to bear on the issues. Individual projects have addressed: causes of spontaneous combustion including the relative reactivities of mine waste materials; the use of cover layers to prevent spontaneous combustion; the use of flyash grout to control an active fire; the emissions of air pollutants; and the emission of greenhouse gases. This paper provides a description of the work carried out to date with an emphasis on the major findings of the research and its application to open cut mines.

Jan 1, 2005

Fast Adsorption Phenomena at Air/Liquid Interfaces

Sep 13, 2010

The principal dirnensions of the chimney were fixed as follows: Height from formation to coping, 328 ft. 8 in.; inside diameter concrete shell, 13 ft. Gin.; inside diameter of the 4~-in. brick lining. 11 ft. (j in. ; shell thickness above flue inlet at a point 39 ft. above formation, 1 ft. 8in.; shell thickness at coping, 6 in. That is, the inside of chimney is cylindrical, wldst the outside is gradually stepped inwards with of 1 in. and less until the shell is 6 in. thick only at the top. With these dimensions in mind, it will be seen that some close thought was necessary to ensure a satisfactory of fonn which could be kept rigid and plumb to a height and at the same time provide safe working conditions for the labourers employed.FOUNDATIONSThe spread base of the chimney is 45 ft. in diameter, and foundations were carried down to a depth of 8 ft. 6 in. below natural surface into good hard clay which was known to be the best foundation obtainable in the vicinity being capable of withstanding, when dry, a load of 3 tons to 4 tons per square foot, whereas dead load is 1A tons per square foot and the maximum load expeeted under the most severe wind condition is 2 tons per square foot to ensure the foundation being kept dry and unaffected by ground water, the site was surrounded by a ring drain at a distance of six feet from edge of concrete foundation and at a minimum depth of one foot below bottom of concrete. Open-jointed pipes were laid in the bottom ofthe drain and graded to a pipe drain with outfall clear of the site.

Jan 1, 1924

By K Heiskanen, R A. Grau

Gas velocity (Jg) measurements conducted close to the froth-pulp interface over the cross-section of a flotation cell reveal how efficiently the incoming air is being dispersed throughout the volume of the cell. Furthermore, measurements of Jg at deepest locations in the cell provide valuable information about air recirculation and dispersion conditions in the bulk volume of the cell. Gas velocity in flotation cells has predominantly been measured by a transient capture of gas in a graduated probe. In this project, a new sensor for measuring gas velocity in an on-line manner was developed. A probe is partially immersed in the flotation machine, below the froth-liquid interface. The probe is used to collect the rising air bubbles from the liquid phase. The liquid-froth interface is shifted into the probe under vacuum. A controlled vacuum is kept inside the probe. As air bubbles burst inside the probe, the excess of air is continuously removed from the probe via suction. The removed air is measured using a mass flow meter. The fully automated sensor allows us to continuously measure Jg at different location in a flotation machine. An experimental programme was carried out in a 10 cm diameter laboratory flotation column to determine the accuracy and repeatability of the automated sensor. The new sensor was used for evaluating gas dispersion conditions in a 215 litre transparent laboratory scale flotation cell. Gas velocity distributions along the radial and axial directions of the cell were measured over a wide range of operating conditions. The operating conditions in the cell were modified by altering impeller speed and air flow rate. Two different rotor-stator mechanisms were utilised to disperse the air in the cell, the MultiMix and the FreeFlow mechanism. In this paper, a description of the gas velocity sensor is given, and the results of the experimental work are discussed in detail.

Jan 1, 2005

Corrosion is a chemical or electro-chemical attack on a metal by the surrounding medium, and it can be stated in general terms that a non-corrodible metal possesses that property either because there is no chemical action between it and the medium, or because the medium reacts quickly with the metal to produce a thin protective coating.When iron or steel is attacked by dilute mineral acids, for example, the products of the reaction are soluble and the formation of a protective film cannot take place; on the other hand, rusting produces a porous film which flakes away and offers little protection to the underlying metal. However, when chromium is alloyed with iron, its resistance to corrosion is improved because the films produced on such alloys become more adherent and tenacious as the proportion of chromium is increased. Chromium is thus an essestial constituent of the corrosion- and heat-resisting steels.During the 40 years which have elapsed since their initial development, these alloys have made an important place for themselves in in<lustry and commerce, and it is the object of this paper to 'describe typical examples of the many types which are available; also, to give some indication of their particular properties, and applications in the mining industry.NOMENCLATUREVery few of the alloys which are about to be described can strictly be considered stainless, and most are not steels in the sense that they can he hardened by quenching from...

Jan 1, 1951

By D L. Kennedy

It has always been a challenge to accelerate the underground development progress by increasing the advance rate of each development round. Surveys have shown that most of the development rounds have only been pulled 84 per cent to 94 per cent of the drilled length. Where bare detonators have been used as primers, less advance rate is expected. In order to obtain a good understanding of the influence of priming upon the advance rate in underground development, a series of high energy primer trials has been conducted by Orica Explosives in the goldfields using various types of Orica high energy Anzomex « primers. It has been shown that development face has been pulled an extra 140 mm to 420 mm by priming with Anzomex « K primers compared with conventional primers. From all the trials at different sites, we have seen that the face pulled using K primers was more square than that pulled using conventional primers. Virtually, no butts and toe were left on the face developed using K primers. Computer simulation has been conducted using either a conventional primer, a bare detonator or a K primer as initiator. The study compared the predicted crack patterns developed around the toe of the hole and it was deducted that a detonator-initiated hole would leave a butt some 200 mm longer than that from a conventional primer-initiated hole, and a K primer-initiated blasthole would give rise to stronger initial p-wave, promoting crack development around the toe and increasing the ability to pull close to the full depth.

Jan 1, 1999

By D Morton, G Wallace

"Evolution Mining is the sole owner of the Mt Rawdon open cut operation, located 75 km south-west of Bundaberg in Queensland, Australia (Figure 1). It is a massive, volcanically hosted, low-grade gold deposit that exhibits excellent characteristics conducive to low cost mining and treatment.In 2014, Mt Rawdon began investigating initiatives to deliver higher mill throughputs without any significant capital expenditure or modifications to the existing processing plant. Various studies have shown throughput increases are possible by applying more blast energy, essentially by reducing feed size through blasting and leaving less work for the comminution circuits (Brent et al, 2013; Ziemski, 2011; Workman and Eloranta, 2003).Given that 53 per cent of energy used on a mine site is consumed by the comminution circuit, with only two per cent being consumed by drill and blast (Smith, 2013), it makes logical sense for a mining operation to align their drill and blast with their processing plant. The term commonly used when exploring this relationship is a ‘Mine to Mill’ program.Over nearly 12 months, various blasting options and Mine to Mill methodologies were tested at Mt Rawdon. Throughout the journey, it was abundantly clear that the Mine to Mill initiative is not as simple as making one technical or physical change and expecting an improvement. Rather, true sustainable improvements demand a paradigm shift across both the mining and processing cultures, where all departments are aligned and working towards the one outcome. This true overarching Mine to Mill mentality, enabled by Vistis™ 250 high energy bulk explosive, ultimately led to a sustained increase in throughput and profitability of the Mt Rawdon operation.Citation:Wallace, G and Morton, D, 2016. High Energy Bulk Explosives and Mine to Mill Focus – the Mt Rawdon Story, in Proceedings Ninth AusIMM Open Pit Operators' Conference 2016, pp 60–69 (The Australasian Institute of Mining and Metallurgy: Melbourne)."

Nov 15, 2016

By B Hall

The authors have undertaken many independent mine optimisation and operational improvement projects at Australian and international mining operations over the past decade. This work has provided an understanding of the underlying practices responsible for the good long-term performance of some operations, and the failure of others to achieve their objectives. Good long-term performance, and value creation can be achieved through a logical and rigorous process of identifying the optimal mine plan (æThe PlanÆ) that delivers the corporate goals, establishing appropriate performance measures that are aligned with these goals, and ongoing monitoring of compliance with the established targets to ensure the operation reliably achieves The Plan. A number of practical methods have been developed and implemented to assist mining operations deliver their corporate goals. This paper outlines some of these methods, providing some fundamental guidelines that will assist in the establishment, and reliable achievement of The Plan that delivers the corporate goals.

Jan 1, 2006

By I Grewal, B Klein

The Knelson Continuous Variable Discharge (CVD) is a continuous centrifugal gravity concentrator for high-mass yield recovery applications. It has four operating variables that enable control of mass yield, product grade and recovery namely: fluidisation water, bowl speed, pinch valve open time and pinch valve closed time. Plant testing of a pilot scale Knelson CVD6 was conducted to evaluate the effects of operating variables on mineral separation. The analysis of operating variable effects has provided a framework for the development of operating guidelines for the CVD.

Jan 1, 2001

By C Woodfull, S Munroe

Geological uncertainty is reduced by improved understanding of the relationship between regional-scale geological basement features (structure, composition, depth) and known local structural risk (such as recognised structural hazards at the mine). Coal mining and exploration entities can be more efficient and effective in managing geological risk at a range of scales. A more efficient and effective performance in forward interpreting and managing geological risk will result in a more efficient and effective exploration and also incremental or even significant mining cost improvements. In order to improve the understanding of basement features, a new 4D regional structural/basin framework for the Sydney Basin and the eastern part of the Gunnedah Basin has been constructed to provide primarily coal exploration and mining with a more integrated geological framework for ongoing subregional to mine-scale geological risk based studies. The model has been developed from a range of available regional geophysical and geological datasets, of variable detail and reliability, which have been brought together to generate a more robust structural and tectonic model than could be generated with any one single dataset. An initial regional structural model for the Sydney Basin was constructed in 2003 and an update to the model was released in 2005 (SRK Consulting, 2003; 2005). The development and ongoing refinement of the model was undertaken with financial and data support from a number of coal mining industry, gas exploration and government organisations. Prior to, and following the development of the regional structural/basin model and associated Information Base, a number of more area-specific studies have been completed, using the æbasement upÆ assessment approach. The methodology for developing comprehensive structural models, from the basement up, is outlined. The approach can be applied at a country-wide, regional or lease area scale. Case examples of where this approach has been used as an effective and efficient method in improving geological certainty and as a predictive tool to help manage geological risk are also presented.

Jan 1, 2006

By Soma T

Pyrite and Cu-concentrate were roasted in vertically suspended state in an externally heated tube. Tubes of three different lengths of reaction zone were used for three different reaction times. Roasted ores were submitted to chemical analysis and the extent of roasting reactions was determined. In case of pyrite, extent of roasting reactions was not affected much by reactor length and heating temperature (above 500¦C), but was considerably by ore/air ratio. Micro- scopic and XMA examinations led to the conclus- ion that pyrite particles decomposed to pyrrho- tite and then pyrrhotite was oxidized to give Fe-S-0 melt, magnetite and hematite. The extent of reaction was not uniform in all particles but had a wide distribution from unreacted pyrite to completely oxidized particles. Combustion of Cu-concentrate from Kuroko complex sulfide ore ) was unstable under a uniform wall temperature of 450¦C, but proceed- ed rapidly at temperatures above 500¦C. Sticking of roasted ores to the wall of the reaction tube induced choking of the tube, caused by melting of roasted ores, at tempera- tures above 950¦C. Enrichment of oxygen exterted less influence on reaction rate than heating temperature of the tube. Particle size of ore had a big effect on reaction rate.

Jan 1, 1980

By B Banerjee, N Kumar, S Parihar

Rampura Agucha Pb-Zn Mine (RAM) is located about 200 km to the south-west of Jaipur in the state of Rajasthan, India. Open pit mining operations commenced in 1988 and continued to 2018. RAM open pit footprint is the largest in India with length of 2000 m, width 1500 m and depth of 400 m. Development of an underground mine under the operating pit commenced in 2013, through trial mining longhole open stoping with cemented backfill was established as a preferred mining method. Nine years in operations underground mine has reached the production capacity of 4.5 MT, which represent more than 70 per cent of the ore volume mined by the pit. RAM is currently the world second largest underground Pb-Zn mine.

Nov 29, 2022

By D B. Donato

Gold mining cyanide-bearing solutions can pose a risk, cause significant wildlife deaths and adverse public relations and result in non-compliance with regulatory conditions. The International Cyanide Management Code for the Manufacture, Transport and Use of Cyanide in the Production of Gold (the Code) was developed as a voluntary code to encourage industry-wide improvements in managing cyanide responsibly. The Code requires design and implementation of robust monitoring programs for compliance under the following standards of practice: 4.1, 4.4 and 4.9. A robust monitoring regime can be complicated as each processing and tailing system is different. The following systems are commonly used in Australia: carbon-in-leach (CIL); carbon-in-pulp (CIP); heap leach process ponds; tailing waste disposal systems; peripheral discharge, central discharge and in-pit disposal. Some terrestrial wildlife can be denied access by fencing tailing storage facilities (TSFs) or other physical barriers, therefore limiting wildlife interaction with cyanide-bearing tailing and solutions to mainly birds and bats. While wildlife monitoring programs for processing and TSFs contain similar core attributes, it is necessary to adapt monitoring to take into account the site-specific features of each system. These core attributes are discussed in this paper, with reference made to cyanide concentration and associated methodologies. The issue is considerably complicated if tailing solutions are deemed or discovered to be toxic to wildlife. Essentially cyanides are required to be measured to gain an understanding of the concentrations to which wildlife may be exposed. This usually equates to measuring the cyanide concentration of solutions entering and leaving a tailing system. To assess the risk to wildlife presented by tailing and heap leach systems it is necessary to monitor both the hazard (cyanide concentrations) and the exposure (live wildlife species, presence and interaction). These tasks need not be arduous and a system of simple frequent monitoring has been developed and implemented for Code compliance. The wildlife monitoring developed by Donato Environmental Services (DES) and used at mining operations departs from the industry norm. It documents observer effort, live wildlife presence, habitat and behaviour in a tailing system, as well as deaths and carcasses. A greater understanding of wildlife cyanide toxicosis associated with this monitoring approach will enable mining companies to adopt a proactive approach to significantly reduce, or preferably eliminate, the impact on wildlife and assist in gaining Code compliance.

Jan 1, 2007

In 1987 the control strategies at the then ZC Mines' New Broken Hill Consolidated concentrator were a miscellaneous mixture of computer hardware and technology for ISA, grinding and residue thickener control. Field instrumentation was based on current-to-air technology of approximately the 1960s. Decisions were made to rationalise computer and field instrumentation technologies; the object being to consolidate control loops into one system to enable expansion of the system to include all facets of plant operation. The first stage was to install a DEC Micro PDP 11/23 computer and serial line communication as recommended by AMDEL Ltd, for the ISA system, as discussed by Walsh and Freeman (1988). The second stage was to select and install a distributed control system for the centralisation of the control loops into one system, and to replace field instrumentation with state-of-the-art technology. This paper deals with the second stage of the rationalisation, in an attempt to give an insight into what is required when personnel are faced with such a decision, details of costs involved in keeping a system functioning and utilised; and the requirement to train personnel for acceptance of further control strategies.

Jan 1, 1991

Sishen uses a state-of-the-art tracking system to track material from its position in blast blocks through various stockpiles and crushers. Qualities are blended directly to the crusher as opposed to blending from stockpiles. This poses an interesting challenge to the planning department to simulate these conditions. The software used in these simulations are Whittle 4X and Maximiser for long-term planning, Xpac for medium-term planning and Mine Works Planner for short-term planning. Geological models and mine design layouts utilise Surpac. Sishen introduced Xpac a number of years ago; the system has developed and changed over the years. With the Sishen Expansion Project (SEP), which aims to utilise low-grade material, major changes to the planning process have to occur. SEP requires that the mine have two different plants, which utilise two different ROM feeds and have different beneficiation curves. Xpac is used to produce a rolling 18-month plan, which is as close to actual operations as possible. In order to do this, the simulations have to take into account the plants beneficiation curves, stockpile movements, hauling distance and equipment needs. On top of this, the schedule has to continually consider specifications for Fe and the contaminants. Plant yields also have to be kept within a certain bandwidth. Xpac is used to simulate the above parameters, as well as generate the raw data required to produce a mine budget. The paper will also show how the 18-month planning process and subsequent planning processes are measured and aligned. Xpac has proved to be an excellent tool to achieve these goals.

Jan 1, 2005

By W F. E Ouedraogo

This study data has been collected on a three-month period from November 2020 to January 2021 and based on three different pits: Vindaloo Main, Vindaloo Central and Bouere. Both pits having specific geotechnical and geological properties. Vindaloo Main, VIM, and Central, VIC, have the same mineral composition as volcanic tuff with felsic intrusion or monzodiorite, both rock mass is fractured with small joint. Geotechnically the uniaxial compressive strength UCS between 200 to 300 Mpa, Young’s Modulus 110 Gpa and Poisson’s ratio between 0.1 to 0.2. Bouere pit is basically made of volcanic tuff stock works as intrusive, UCS between 200 to 300 Mpa, Young’s Modulus 103 Gpa and Poisson’s ratio between 0.2 to 0.3. The first step of this study was to collect various data from mining operations around the drilling and blasting inputs. This was based around the different scenario of drilling parameters and the outcomes on the blasting, and how they impact load and haul operations and productivities of excavators from the heave to the last flitch. In most cases surface photos of the blast do not represent the overall fragmentation in the blast volume. Photos of the different flitches will not show only the effect of blast, as the loading operation generating more fragmentation by applying weight on the muck pile. Then the record of the different material uses for feeding. The last part of the analysis is the physical data from process plant such as particle size, throughput rate, both for the crusher and the mill, per pit and material and the specific Bond Work index (BWI). Fine particle quantity production is also a key point as is one direct indicator of milling performance. In overall, making link to BWI can influence at each stage of the mining to the processing operation. Drill and blast constitute a high cost in hard rock mining and trying to reduce these costs without an overview of all the integrated processes and context could end up by cost relocating to other activities in the process. However, the cost associated to size reduction builds exponentially as the particle size becomes smaller.

Jun 22, 2022

By D Lichti

This paper presents recent advancements in the MillMapper software technology, developed and used for thickness gauging of liners of cylindrical grinding mills used for mineral comminution. MillMapper uses calibrated laser scanner data captured inside a mill to determine thickness at several million points on all liner surfaces with millimetre accuracy. The paper is structured as follows. First, a review of the technology and its numerous advantages over existing techniques and the value it adds to operations are presented. These are followed by discussion of recently-implemented innovations, including improved visualisation and inspection tools, automatic ball charge volume measurement and automatic mill liner volume/weight measurement. Results from its application at several sites in Australia are presented throughout.

Jan 1, 2007

By A L. Zawadski, B G. Putland

"This paper discusses a method to build a calibrated comminution circuit model, using historic operating data and blend information that is useful for forecasting and optimising plant performance, as well as evaluating expansion opportunities. A preferred method for building a calibrated power-based comminution model is discussed and justified based on two case studies, offering low-cost and effective strategies to utilise existing information for the maximum possible benefit.The first example is the Lefa Gold Mine located in Guinea, West Africa operating a semi-autogenous grinding (SAG) and ball milling circuit with recycle crushing (SABC). Daily blend information and operating data was utilised to build and calibrate a power-based model of the comminution circuit. The least squares regression method was used to solve the SAG mill specific energy requirement and the operating work index (Wio) for each individual ore type. The calibrated model was used to evaluate expansion strategies to sustain throughput at higher proportions of fresh ore based on the proposed life-of-mine schedule.The second example is the Ok Tedi Copper-Gold Mine in Papua New Guinea operating a SAG and ball milling circuit (SAB). The circuit limitation would often shift between the SAG mill and the ball mill due to variable ore characteristics and feed blend. Typical SAG mill relief strategies, such as recycle crushing or secondary crushing, required significant capital expenditure and the potential throughput benefit would vary depending on ore type, making economic justification difficult. Daily blend information and operating data was used to build and calibrate a power-based model of the comminution circuit to identify ore types that might benefit from higher blast intensities to increase fines content, thus relieving the SAG mill limitation and increasing overall throughput without a major capital investment.Citation:Zawadski, A L and Putland, B G, 2016. Calibrating Comminution Models Using Operating Data to Forecast and Optimise Plant Performance, in Proceedings 13th AusIMM Mill Operators’ Conference 2016, pp 17–26 (The Australasian Institute of Mining and Metallurgy: Melbourne)."

Oct 10, 2016