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By Littlewood E

We offer these notes as a practical contribution. All the arguments we advance have been tested by practical experience.In its preparation we realised that our subject was one of such importance and covered so wide a field that, dealt with by one of us alone, it might easily have been too much for him, so we have endeavoured, by mutual criticism and advice and a pooling of ideas, to bring forward a few points that may be of advantage to members. If any of the paper is of benefit to mining on the "Golden Mile," or elsewhere, we shall feel amply repaid for our efforts.It is obvious to all that the longer the machine is working productively per shift the greater the return, to all concerned; the machine-man himself and the company. Furthermore, if a man commences a shift with a definite objective in view; for instance, to bore and fire a specific cut, which he recognizes will give him a good financial return, then that man will exercise all his capabilities to attain that objective.In this paper we hope to demonstrate the value to the machine-man of the knowledge of the capabilities of each hole he bores, so that he will be enabled to utilize his drilling time to the greatest advantage. Also, we hope to show that such drilling time can be advantageously extended.After the war, with the influx of new men to the industry, some education on the finer points of machine work may be desirable, and any instruction in this branch must stress the realization of the value of each hole.We realise that most of those present have a sound workable knowledge of machine-mining, and we are not trying to teach anyone the fundamentals of machine work, but we would like to bring to their attentIon some of the finer points which we believe are very important.The machine-man has control of gear of a capital value of over £150, and the use or misuse of that material has a direct bearing on working costs. Therefore it is imperative that the capital outlay is gainfully employed.A "bogger" in charge of a 5/- shovel engaged unproductively is bad enough. How much worse for £150 worth of gear to be not fully productive.Figs. 1 and 2 demonstrate angles of break, and the full realization of the importance of this angle is essential to our paper. Although these Sketches are two-dimensional, we hope they will be sufficient to demonstrate our meaning. We will pass over them as briefly as possible.Fig. 1 shows three holes asked to perform an identical task.(a) 7-ft. hole bored 2 ft. into solid ground-will not come out.(b) 4-ft. hole bored 1 ft. from solid ground-will come out easily.(c) 5-ft. hole bored to solid ground-the best that can be expected under general conditions encountered.The angle of break is a right-angle, normal to direction of hole.

Jan 1, 1944

Extensive reserves of kaolin of the type suitable for use as a high quality paper coating exist on the Weipa Peninsula. In 1986 a commercial processing plant was constructed to produce 100 000 tonnes per annum of coating quality kaolin targetted principally for export. A number of processing difficulties have limited the production capability of the plant. The prime area being the pressure filtration operation with achieved cycle times being around 50-60% of design. The rate determining steps being press filling, press unloading and filter cloth washing. This paper details and summarises testwork and results from our attempts at decreasing the filtration cycle time.

Jan 1, 1989

By Mitchell M. A

The steeply dipping Mammoth orebody is mined by Gunpowder Copper Limited using a sub- level uphole bench stoping method at a mining rate of 350 000 tonnes per year. of three per cent copper ore. Access to the mine, is provided by 1 in 9 decline which spirals in the footwall connect-, ing all the sublevels, thus maximising mobility and accessibility of trackless mining equipment Sublevels are driven in ore off cross- cuts from the decline every 15 metres vertic- ally. Sublevel drives are stripped out to widths up to 18 metres before cutoff slots are mined at each end. A two boom fan drilling jumbo is used to drill inclined rows of holes to the floor of the sublevel above. Two or three rows are fired at a time which allows broken ore and remnants from the level above to be mucked out by rubber tyred LHD equipment to the brow. Ore widths of up to 80 metres are en- countered at lower levels where ring drilling from longitudinal drill drives will break ore to a draw point system below. Development is carried out with three boom rubber tyred jumbos. All haulage from the mine is in 20 and 35 tonne rear dump trucks. All aspects of the mining operation are discussed including ventilation, pumping and drainage, services and future planning.

Jan 1, 1974

By Costello MC

An alternative process for desorbing and recovering metals from activated carbon has been developed, and is the subject of several patent applications by Micron Research (W.A.) The system uses the principle of conditioning the carbon in a strong alkaline cyanide solution followed by distillation desorption in a fractionating column, using the carbon as the column packing and methanol as the desorbing agent. The system offers the following advantages : (a) The processes of desorption, methanol recovery and reactivation are all carried out in a single column with the carbon itself acting as the column packing. No other desorption plant items or fractional distillation equipment are required. (b) The metal values are concentrated into the water content of the carbon and no other water is used except as condenser coolant. This produces very high grade gold silver solutions which give high current efficiencies in the electrowinning step. These high gold concentrations allow almost complete separation of gold and silver from copper in the electrolytic cell. (c) The process is completed to a tailing assay of less than 200g Au/tonne carbon in 15 - 20 hours allowing turn around of carbon batches on a daily Basis.

Jan 1, 1982

By Gonzalez-Dominguez J. A, Dreisinger D. B

At Cominco's Zinc Refinery at Trail, British Columbia impurities are removed from zinc sulphate electrolyte by a two-stage purification process using zinc dust. Copper, cadmium and thallium are removed in the first stage whereas cobalt is removed in the second stage. Cobalt removal kinetics are affected by soluble antimony and copper additions to the electrolyte. This study was focused on the kinetics of cobalt removal by zinc powder cementation. Experimental variables included copper and antimony concentrations, pH and temperature. Common organic additives employed in zinc plants were studied to determine potential interactions with the cobalt removal process. Cementation products obtained from laboratory experiments and plant practice were studied using SEM. A number of significant results were obtained: 1. Copper and antimony ions were sustantially removed from solution during the early stages of the cementation reaction (within the first 15 minutes). Cobalt cementation kinetics are slow and follow a first order kinetic regime. 2. A drop in the cobalt removal rates can be correlated with a rise in the Eh of the slurry. 3. Ligninsulphonate, Percol 351 and animal glue at levels of 2 mg/L significantly impede cobalt cementation.

Jan 1, 1993

Diamonds have been known in Australia for many years, especially in association with alluvial gold and tin occurrences. Exploration for primary sources in the Kimberely area of Western Australia has been carried out since 1968, culminating in the discovery, in 1979, of the Argyle Kimberlite No 1 (AK1) kimberlite pipe. Various techniques have been used in the search for diamonds such as geologic interpretation, aerial photography and Landsat, soil geochenical techniques, geophysics, and stream sediment sampling. Stream sediment sampling, a method developed in South Africa, using the detection of indicator minerals derived from kimberlites in gravel samples, has had wide application and success in Australia. Nevertheless, although Australian diamond bearing kimberlite and lamproite rocks contain some of the classic indicator minerals, their concentrations are generally much lower than in South Africa and Russia. Despite this paucity of indicators, stream sediment sampling is still the best known and most commonly used method of diamond prospecting in Australia. Small samples are treated by hand but larger samples require the use of diamond pans, jigs or heavy media separation plants. Each of these methods has advantages and disadvantages. The final concentrate is passed over a grease table or subjected to x-ray sorting.

Jan 1, 1984

By Jowett A

To compare open circuit lead primary rougher results at Mount Isa Mines Ltd., eleven surveys were made over five weeks of plant operation with varying ore sources, including a specially hauled sample of 100% Black Star ore. Three of the surveys which represented extremes in performance were selected for sizing, cyclosizing and assaying for lead, zinc and iron. A comparison of the flotation kinetics has revealed the similarities (including common problems) and differences for the surveyed ores. The concepts of entrainment and collectorless flotability are used to aid interpretation of the kinetic data.

Jan 1, 1978

By D H. Bell

Slab-buckle failures in coal sequences involve thin slab deformation in strata dipping parallel to the footwall, and are a consequence of both unloading and the weak nature of the thinly bedded rock mass. Methods of modelling and predicting such occurrences include: +        a conceptual model using a base friction table, +        a mathematical model using the Euler solution for column and beam bending (after Goodman, 1980), and +        computer analysis techniques such as UDEC (Universal Distinct Element Code after Cundall and Hart, 1993).   Slab-buckle failures have the potential to seriously disrupt production because of their volume and rapidity, and to endanger both equipment and personnel working on the pit floor.   In July 2004 a large slab-buckle failure occurred overnight after a new batter and bench had been formed at the Malvern Hills Opencast Mine in inland Canterbury. This involved the entire length of the pit (85m along strike) when a 2m thick intact slab with a total volume of ~3500m3 translated down dip 6.2m on the base of a thin coal seam to form a pronounced buckle at the toe. The coal measures consist of finely laminated mudrocks with multiple coal seams of varying thickness dipping ~45¦ to the southeast, and the opencast mine had been designed with footwall batters formed parallel to bedding with a vertical bench separation of 15m.   Back analysis of the Malvern Hills failure was necessary to investigate the controls on footwall instability, and for future mine design. An engineering geological model was created and samples of the slab material and failure surface were collected and tested to establish the required parameters for use in the Euler solution for column and beam bending. Back analysis using the Euler solution provided unrealistic results that overestimated the overall length of a stable slope by more than 10 times.   No further large scale slab-buckle failures have developed at the mine site, in part because of the slow rate of coal extraction, but precautionary drainage of the footwall slopes has been undertaken to improve overall batter stability. The location of the slab-buckle failure on a critically positioned pre-sheared thin coal seam with full hydrostatic head is considered the most probable cause of the July 2004 failure, rather than inherent instability of the generic bench and batter arrangement adopted. The use of a precedent-based engineering geology approach to future mine design is considered the most appropriate solution in the circumstances.

Jan 1, 2007

By Savory P. J

Uranium mining operations commenced at Ranger mine site, Jabiru NT Australia in May 1980. The Ranger orebodies, totalling approximately 110 000 tonnes contained U305 had been indicated by airborne radiometric survey in 1969 and confirmed by drilling the following year. Both diamond and percussion drilling methods were used to define the mineralisation and samples were analysed using a combination of radiometric and neutron activation techniques. Ore reserve estimates were calculated from conventional and geostatistical methods, and following the mining of 15 million tonnes of ore, reconciliations with before mining estimates are well within acceptable industry standards. In-pit grade control employs radiometric techniques including a radiometric truck discriminator built in Australia to mine specification to meet production requirements and improve productivity. Environmental requirements associated with uranium mining are a daily consideration.

Jan 1, 1993

To reflect on the early history of mining in South Australia requires considerable imagination and rashness. The people who were the chief actors in the scene have long since passed away. Accounts of their activities are hazy and debatable. A broad brush account is all that I can hope to accomplish under these circumstances. It is fitting that a picture be painted and possible lessons learnt from the achievements of our pre- Decessors.

Jan 1, 1987

By Peck J. P, Kennedy D

Drill performance monitoring studies were recently completed at the Fording River mine, British Columbia. Microprocessor-based instrumen- tation and data analysis techniques were developed with the objective to improve short and long term mine planning. Data analysis permitted the identification of thicknesses and interfaces between soft/hard zones at depth based upon the recorded responses of the drill. Data clearly con- trast the soft coal seams and harder waste rock units based on variations in recorded drill rotary speed and torque, hydraulic downpressure, bail- ing air pressure and instantaneous rate of penetration. These parameters were monitored and recorded at 10 cm sampling intervals. Processed drill data was correlated with gamma logs, an existing means for locating coal seams and distinguishing between waste units. Current development of a pattern recognition module aims towards automated interpretation of drill data, identifying micro-and macro-geological and geomechanical rock mass characteristics. Delay between acquiring, processing and interpret- ing the drill data for practical use by mine personnel should be minimized. Integration of this technology with the mine's current main-frame based Mine Engineering Application System software will enable more accurate and timely annlication of the nrocessed drill data.

Jan 1, 1989

By Zhen Y. Y, Cook A, Jell J. S, Fleming P. J G

Remapping of the Burdekin Basin has resulted in subdivision of the three interfingering basin-wide megafacies previously recognised in the Early to Middle Devonian Fanning River Group. Eleven carbonate and siliciclastic facies are now identified within the three megafacies, representing coastal plain, shoreline, nearshore, and shallow marine shelf depositional environments. The facies reflect two phases of a major transgression. An initial phase, in the Early Devonian, was confined to the far north of the basin, whereas a second, main phase, resulted in the encroachment of the sea from the east or southeast in the Middle Devonian.The proposed depositional model begins with the drowning of a coastal plain and the transgression of shoreline and nearshore facies between granitic and metamorphic headlands and/or islands. This was followed by the deposition of a patch reef and fringing reef complex including stromatoporoid and coral bioherms, biostromes, and oncolitic, crinoidal, and brachiopod-dominated banks/shoals, together with foreslopes and submarine channels, carbonate rubble deposits and terrigenous sediments. Sedimentation during the peak of the transgression was dominated by sheltered carbonate shelf facies, the maximum, flooding surface being recognisable across most of the Burdekin Basin. Progradation of muddy and sandy nearshore bay and shoreline facies soon followed, terminating carbonate deposition.

Jan 1, 1990

By Anderson K

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

Jan 1, 1993

This paper explores options worthy of consideration in the management of S02 produced from the gold roasting operations at Kalgoorlie. Some of the options have relevance to other sources of SO2 in the region, eminating from nickel smelting operations. The paper considers the following options: 1. Capture of SO2 within the roaster where sulphur-containing reaction products are mixed with the calcine. 2. Processes in which the sulphur-containing products are bled separately from the stack for further treatment or for dumping as a waste. These include: Seawater-based scrubbing of SO2; Sulphuric acid manufacture as a feedstock for fertiliser production or for leaching of bauxite; its use as Caro's acid: and the production of value-added sulphur-containing reagents eg liquid S02 and sulphonic acid.

Jan 1, 1992

Alternatively are they a necessary evil'? Exploration geologists are a much higher profile group but then again the higher they are the bigger they Bill. At a mine site they are reluctantly being accepted as equals by mining engineers given the requirements of the `Code' in the reporting of Ore Reserves. How best can mining geologists service their customers? Are more revealing questions to be answered in who are their customers? In the past mining geologists lived isolated existences pouring over plans and sections, now with user-friendly software packages available and the use of LAN, mining geologists and mining engineers talk electronically - God forhid what the future might hying - they might even talk to accountants and metallurgists!

Jan 1, 1997

By Little T. N

The Western Australian School of Mines is continuing to investigate the blasting techniques and mining strategies that are used for ore/waste separation (or high grade/low grade ore separation) or to prevent ore and waste mixing. The aim of all the mining strategies is to produce an optimum product. The optimum product is one which contains no diluent and undergoes no mixing of the various identified ore and waste blocks and is fully recovered at the minimum overall operating cost. The current study includes the use of computerised Knowledge Based Systems (KBS) technology to assist the user with the blast technique selection and blast design process. These aspects are highly dependent on the geology. (geometry, rock mass properties, grade distribution), explosive performance and the expectations of the mining company in terms of production rates and equipment utilisation. Most of these factors are not well defined and nor are they easy to quantify. However, a large amount of knowledge does exist and is available in the following forms: rules of thumb, empirical formulae, engineering judgement and past experience. KBS techniques are well adapted to handle such"forms of knowledge. The primary objective of this paper is to illustrate an approach for the use of Knowledge Based Systems during the analysis and interpretation stages of the blast design process. In particular, the components and methodology of the developed system are described for selective open pit gold mining. The Knowledge Based System developed was written using the declarative programming language PROLOG.

Jan 1, 1990

By Shrivastava P, Humphreys M, Guibal D, Deraisme J

Customer requirements concerning the final products of iron mines are extremely stringent. Because of this, there is an ever-increasing need for mine operators to monitor and strictly control the quality of their product. This quality, as measured by the stockpile grade variability, is the result of a very complex process, where natural characteristics (the orebody and its geology) are transformed through the mining technique (open pit, shovel and truck fleet, blending into stockpile). The only way to reproduce and hence to control the variability of such a system, which is composed of several interactive sub-processes, is by simulation. A complete simulation of a Hamersley Iron Pty Ltd (HI) ore deposit has been undertaken to forecast the impact and cost of various mining methods, mining schedules and product stockpile sizes on variability of chemical and physical characteristics of the products. The mining simulation was made on a conditionally simulated orebody. On a range of criteria, the simulation was considered to fulfil the objectives set and was a valuable aid to analysis of product grade variability, operating and capital costs, selection of equipment, mine scheduling and setting of product grade targets.

Jan 1, 1994

Degussa's PAL-system (peroxide assisted leach) has been proven to be more economical than the conventional cyanidation technique. Significant in- creases in the gold recovery have been reported, accompanied by savings in cyanide. Accelerated extraction kinetics and modified reagent demands necessitate a redesign of the conventional cyanidation plant. The South African Osprey Mine is presented as an example of a successful PAL-application. Based on the plant and laboratory data it is shown that the redesign of the flowsheet can be an important factor for the effectiveness of a metallurgical plant. In the case of the Osprey Mine, the PAL-technology all ows a modification of the current preoxidation-ClPcircuit to two separate CIL-plants to treat run-of-mine ore and old tailings dumps. A doubling of the throughput is possible without enlargement of the plant. This innovation in the field of gold extraction, the combination of the PAL-process with a redesign of the metallurgical plant, can be considered as a basis for a more profitable gold mine.

Jan 1, 1991

The incidence of colliery disasters has highlighted the need for more centralised and directed coal mining safety research in Queensland, with particular impetus from explosions at Box Flat in 1972, Kianga in 1975 and Moura No 4 in 1986. Inquiries which identified the likely causes recommended measures and, research and two outcomes have been the present Mines Safety Research Advisory Committee and The Safety in Mines Testing and Research Station at Redbank, near Brisbane, dealing with all mining problems, coal and metalliferous. Already, important research into ignition and explosion and other health and safety matters has been accomplished; the Station has become an accredited testing laboratory; and international recognition has been achieved. Now the advisory, testing and research arms are soundly in place to pursue preventive investigations and be ready to provide assistance in any emergencies.

Jan 1, 1991

By Hanaoka K, Ikeda K

Kakogawa Works, Kobe Steel, Ltd. has two pelletizing plants and one sintering plant, and the blast furnaces have been operated with 30 - 50% pellets. At Kakogawa Works, various improvements in pellet quality have been carried out since the beginning of operation of the pelletizing plant. Especially, dolomite-fluxed pellets developed in 1975, have superior high temperature properties. The fuel rate of the large blast furnaces at Kakogawa Works has been reduced to 450 kg/t- hn by using a high percentage of dolomite-flux ed pellets.

Jan 1, 1980