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Recovery of tin and copper from concen trates containing cassiterite, stannite and chalcopyrite was studied in laboratory-scale tests designed to simulate continuous operation of the matte fuming process in which tin is recovered as SnS fume while copper accumulates in the matte. Charges made up of 300g of mixtures of the concentrate and siliceous flux were added at a uniform rate in pelletized form to crucibles containing 300g of matte and 50g of slag (both of which were recovered from previous tests), while blowing through the matte with air or oxygen-nitrogen mixtures at a rate of 3 to 5 1/min. Accurate material balances enabled the effects of process operating conditions on tin recovery and sulfur utilization to be deter- mined. When operated correctly, the matte fuming process gave tin recoveries exceeding 90 percent in spite of wide variations in the copper content of the matte and in the operat- ing conditions. Deterioration of tin recovery was associated with undersaturation of the slag with respect to silica, and with high partial pressure of sulfur dioxide (greater than approx- imately 0.2) brought about by oxygen enrichment of the blowing air. The utilization of sulfur varied widely in low grade mattes. Copper in excess of approx- imately 10% promoted formation of SO2 by the commonly accepted reaction: FeS + 1-120 2= FeO + S02 while in copper-free and lower grade mattes a substantial fraction of the oxygen was consumed in the alternative reaction FeS + i 02 = FeO + z S2.

Jan 1, 1980

By Ellery B. I

Field investigations recently undertaken by Utah Development Company (U.D.C.) have been developed to allow the assessment of ground conditions relevant to the use of large bucket wheel excavators for pre-stripping overburden. "Bucketwheel diggability" predictions were made on the basis of a wedge test which was perform- -ed in the field on nominal 150 mm diameter drill core samples. Specific separation force (calculated from the wedge test results) for different rock horizons were theoretically related to the excavation rates of various sized bucketwheels, i.e., "bucketwheel diggability". The specific separation force was shown to vary with lithology, structure, weathering and moisture changes. By correlating these features between boreholes, an overall assessment of bucketwheel diggability was then made. The approach adopted to assess bucket- wheel diggability incorporated various levels of investigation. Initially, a reconnaissance stage provided information from widely spaced 150 mm cored holes to compare and contrast areas with differing bucketwheel digging char- -acteristics. The following stages progressive -ly added to this information, until finally, between hole correlations, allowed calculations to be made of volumes of materials of similar

Jan 1, 1981

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 G Gibson, B Bessen

In coal preparation, large dense medium cyclones (DMC) at low pressure heads (typically 9D where D = cyclone diameter) are the norm. This contrasts with high density mineral applications where, largely for historical reasons, smaller cyclones at high heads are the standard. There are advantages in preferring large diameter cyclones at low heads, assuming that metallurgical performance does not suffer significantly. These include simpler plant layouts, easier maintenance, smaller spares inventories, reduced wear, reduced medium pumping demands, smaller buildings and overall lower capital and operating costs. In 2008, therefore, Xstrata Zinc decided to trial a single DSM-design 800 mm cyclone in one of its four DMC lines at Mt Isa, replacing the four 400 mm cyclones previously installed. Circumstances allowed a low head of 9.5 D to be trialled, compared with the existing 400 mm head of 21.5 D. This paper describes the trial, including tests using painted ore particles as tracers, estimates of yield and metal recovery, and wear monitoring. The larger unit performed well. There was no evidence that metallurgical performance in terms of metal recovery and waste reject rate suffered, and there was some evidence that it may have improved. Cyclone life increased, and preliminary data suggest that the replacement cost of the 800 mm cyclones is less than half that of the 400 mm units, and this is expected to improve. The plant layout and operability have also improved significantly. Xstrata has therefore decided to convert the whole plant to four low head 800 mm units, replacing the original 16 high head 400 mm units. The paper includes an explanation of the effect of static head on DMC separating force. It also reviews earlier research on diamond applications, and applies a general DMC process model to the Xstrata case, both of which confirm that large, low head cyclones are appropriate in mineral applications, contrary to conventional practice. Such units could significantly reduce both the capital and operating costs of DMC plants in mineral applications.

Jan 1, 2009

By Robinson B, Ham B

Outbursts have occurred irregularly in the Collinsville Coal field since 1954 when an incident claimed seven lives. Further significant outbursts occurred in 1960, 1961, 1972 and more recently in the No. 2 mine in 1978. From the information collected over 25 years a comprehensive program to minimize the hazard of outbursts has evolved. Further developments of techniques to combat outbursts are being developed.

Jan 1, 1980

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 Artmont G. J, Palmer K

Alluvial gold is an ideal exploration tracer to bedrock source and indicator of bedrock mineralisation style because (i) gold occurs in a wide range of deposit types, (ii) primary composition is sensitive to style of mineralisation, and (iii) it is a heavy resistate mineral that is readily preserved and easily sampled. In regional exploration of the Central Ranges of Irian Jaya, alluvial gold mineralogy has been applied to maximise the information return from panned concentrate sampling and to focus exploration effort. Primary gold is a solid solution of Au+Ag¦Cu¦Hg, ¦ trace Pd, Te, and Sb. In general Ag¦Hg increase and Cu decreases with inferred decreasing temperature of formation, and gold from particular mineralisation styles has signature compositions that can be used as indicators of bedrock mineralisation type. Furthermore, the abundance of alluvial gold is an indicator of the economic potential of a catchment. The convergent continental-oceanic plate geology of the Central Ranges is conducive to a wide range of mineralisation styles. Mineralogy of gold in ophiolite, skarn, porphyry, mesothermal vein and possible VHMS environments is characterised from alluvial and bedrock samples, and the use of gold mineralogy in prospecting at regional scale through prospect definition to drilling is demonstrated.

Jan 1, 1995

Proceeding from statistical data on the development of waste volume, an endeavour was made to characterise waste materials with regard to the applicability of treatments based on mineral processing. Many types of waste are characterised by a high heterogeneity. The separation processes used for processing raw minerals can also be used for separation of various waste mixtures. For some waste mixtures, differences in properties can be utilised for separation which are mostly less distinctive for raw minerals. State-of-the-art technology is illustrated with selected Examples.

Jan 1, 1993

By Campbell Brown G A

IN 1904-5 diamond drilling operations in the Mount Morgan mine proved the presence of some millions of tons of rich copper-gold ore, averaging about 45%to 50%silica and 22%Fe as sulphide. To smelt this ore in blast furnaces, without previous concentration, large quantities of basic flux were required. Unlimited quantities of cheap limestone were available at Marmor, on the GladstoneRockhampton railway, 50 miles from Mount Morgan, but the supply of iron flux was a more difficult problem. Smelting Operations started with one furnace in January, 1906, using as flux low-grade sulphide ore from the mine, containing very little silica. When the second furnace was blown in this was supplemented by ironstone from small deposits in the immediate district. It was recognized that these sources of supply would be insufficient to keep the full plant going after the third furnace had been blown in. Accordingly, the deposits at Kabra and Mount Etna were opened, neither of which proved capable of supplying the quantity required-viz., 1000 tons per week. Negotiations were meanwhile being conducted with the Marble Island Iron and Limestone Co. to obtain the right to mine at Iron Island, where a sufficiently large deposit was known to exist. Shipments from this source commenced in January, 1907, and ceased at the end of July of this year, when the metallic flux from...

Jan 1, 1911

By Johns A. L

The concept of the Melbourne Underground Rail Loop and the organ- isation to achieve its construction are covered in the companion papers (Reference 1, 2) and will not be repeated here. The Victorian Railways, as well as being the eventual operator of the Loop when it is completed by MURLA, have also been responsible as "Contractors" to MURLA for the construction of the "cut and cover" or "box" tunnels and related approach works located on existing Railway property. These tunnel connections link the existing suburban system to the new underground works. The following tabulation indicates the significant work volume involved in this cut and cover tunnelling exercise and which is covered in some detail by this paper.

Jan 1, 1981

Design of cemented fill in mining is often carried out without any consideration of the structure of the fill. The composition of cemented fills varies in the stopes due to the placement method, and the strength of the fill in the laboratory depends on the density, orient- ation, moisture content and drainage conditions. Within each stope there are definite zones and the structure of both cemented rockfill and cemented hydraulic fill has to be defined for each zone and the field conditions simulated in the laboratory. Structure also affects fill permeability and compressibility. From a study of the cemented fill in place, the effect of changes in the placement methods can be seen and then controlled to improve fill performance and economy. These features of cemented hydraulic fill and cemented rockfill behaviour are discus- sed and illustrated through reference to field and laboratory work undertaken at Mount Isa.

Jan 1, 1973

This paper reviews the issues of mining machinery automation with special emphasis on underground applications. Automation is desirable because it offers the following advantages: ò increased safety by reducing human exposure to hazards of underground mining; ò higher productivity; and ò reduced wear of equipment. In spite of these advantages and in spite of numerous attempts over the past several decades, mining automation has been a difficult proposition, partly because no two mining operations are exactly alike and these operations are carried out in an unpredictable environment. This is the main difference between automation in factories and in mines and that is why mining automation has been lagging so far behind factory automation. Automation is possible only when the machine 'knows' its workspace. In a factory, this workspace can be 'described' to the machine because it is sufficiently controlled. In a mine, the environment undergoes continuous change and the only way the machine can 'know' its workspace is through real-time sensing.

Jan 1, 1995

By S Meffre, S Golding, K Zaw, J McPhie, R James, S Suphananthi

The Chatree deposit is located in the central portion of Loei Fold Belt, which extends from Lao PDR in the north through centralThailand to Cambodia in the south. Epithermal gold-silver mineralisation at Chatree occurs as veins/veinlets and stockworks with minor breccia in volcaniclastic and volcano-sedimentary rocks of andesitic to basaltic andesite composition and Permo-Triassic age. This preliminary oxygen isotope study mainly focuses on vein quartz of Au-Ag bearing mineralization (Stage 2) and a few samples of late Stage 4 quartz ¦ calcite veins. Quartz from Au-Ag bearing mineralisation has oxygen isotope values ranging from 8.1 to 12.3ë with the lowest values generally occurring at the deeper level (140 m below the surface). The late barren quartz ¦ calcite veins (Stage 4) tend to have higher oxygen isotope values ranging from 11.9 to 12.0ë. The oxygen isotope composition of the Chatree ore fluids were calculated at 250¦C, 300¦C and 350¦C based on homogenisation temperatures of fluid inclusions. The calculated oxygen isotopic composition of the Chatree ore fluid ranges between -1 and 6ë that overlaps with both meteoric and magmatic compositions. This shift in oxygen isotope compositions may relate to processes such as water rock-interaction and/or mixing of meteoric and magmatic fluids. It is interesting to note that the lowest quartz oxygen isotope values are spatially more or less confined to the prominent structures in the centre of the major ore zones. These structures may have been acted as conduits for higher temperature magmatic fluids. The quartz oxygen isotope values increase outwards from the centre of the main ore zones to the margin of the pits possibly due to mixing of magmatic fluids with lower temperature meteoric water. Whole rock oxygen and hydrogen isotope studies are in progress to investigate isotopic trends in the wall rock away from the ore zone. The systematic variation of oxygen isotopes in quartz from the mineralised veins and adjacent wall rocks could potentially be used as a vector to ore. An EXTENDED ABSTRACT is available for download. A full-length paper was not prepared for this presentation.

Jan 1, 2008

Jarrah Decline is currently the only underground operation at the Boddington Gold Mine, (BGM). The mine is located 120 km SE from Perth in WA, with mineralisation hosted within deeply weathered felsic and intermediate intrusions and volcanic rocks of the Saddleback Greenstone Belt (Morley and McBride,1995). Open cut operations commenced in April 1987 with a mill throughout of 3.OMtpa. A number of upgrades have since taken place, with the oxide material throughput currently milled at a rate of 7Mtpa. In 1992 a separate circuit, the supergene mill, was commissioned to treat copper material from the open cut and now ore from the Jarrah Decline. Current throughput in the supergene plant is 30,000 tonne per month, with a varied blend according to mill requirements. Total gold production from the Jarrah Decline in 1994 was 60,000 ounces from 90,000 tonne of ore.

Jan 1, 1990

The South American mining community leads the world in recognition and adoption of the latest grinding mill relining technologies. Clearly this region has recognised the benefits of improved relining performance as a defence against the Global Economic Crisis. Five of the six RUSSELL TWIN 8 Mill Relining Systems, ordered to date, are either operating or being manufactured for South American mine sites. The sixth is for Sino IronÆs Cape Preston Project in Western Australia. This paradigm shift, towards very short relining times, aims at displacing mill relining activities from the critical path of concentrator maintenance shutdown schedules. The first uses of the RUSSELL TWIN 8 Mill Relining System have seen some of the highest semi-autogenous grinding (SAG) mill new liner placement rates ever observed by Russell Mineral Equipment (RME), as would be expected with two, independent Machines working simultaneously in the one mill. The liner replacement rate, averaged over the whole reline is good (27 per cent improvement over single Machine System in the same mill) but short of full potential. This modest result can be attributed to reline crews unfamiliarity with RUSSELL TWIN 8 System operation. This paper compares a sample of conventional (single machine) RME Mill Relining System performance data with one ædouble headÆ mill liner handler by others. Early performance of EscondidaÆs new RUSSELL TWIN 8 System performance is then compared with recent single machine data from Escondida, immediately prior to RUSSELL TWIN 8 commissioning. RME and Escondida look to constantly improving RUSSELL TWIN 8 System performance as full operational familiarity is achieved. The preparation of this paper revealed a need to develop a global industry standard for mill relining data collection. A web based platform to develop data collection templates is also discussed in Appendix 1.

Jan 1, 2009

Geological information plays a significant, cost effective role, in the Mt Whaleback iron ore mining operations. The geology and structure are complex. Good communication between the Mine Planning Production Scheduling and Quality Control Sections is the key to utilisation of geological information to its full potential.Drilling and pit face mapping are the two basic sources of detailed data sets which are processed to prepare up to date geological cross sections and benchwise geological plans. This information is used directly for the blast pattern design and production scheduling. Physical ore type estimation is also undertaken. Orebody models are generated from the geological information.

Jan 1, 1990

Thank you for this opportunity to address your conference on The role of coal in the New Zealand energy market".New Zealand's energy market has, in common with much of New Zealand, undergone major change following the market reforms of the Labour Government.As far as the energy sector is concerned this change has been for the better, as it has created for the first time in a very long time a "true economic market" for energy in New Zealand.

Jan 1, 1990

By Ahmed M, Leung L

A program of microseismic noise monitor ing for gas outbursts, in conjunction with other mining engineering measurements and observations, is being undertaken at Leichhardt colliery in Queensland. Headings are developed at present by shotfiring. The equipment being used in this study includes piezoelectric accelerometer assemblies to detect microseismic noise which is then transmitted to a surface base station by cable. Data are recorded on an analogue magnetic tape recorder and are also analysed on-line using a commercially-available acoustic emission pulse analyser. It is proposed to re-interpret recorded data using various modes of analysis and to interface a desktop computer to the existing system to permit continuous monitoring on the mine site. No outbursts have been recorded or analysed and only a limited number of develop- ment shots, and the resultant microseismic activity, have been recorded to date.

Jan 1, 1980

By Toguri JM

A solid electrolyte technique has been used to measure the activity of cobalt in liquid cobalt-gold alloys containing between 0.085 and 0.50 mole fraction of cobalt, and for temperatures from just above the liquidus to around 1550 K. The system exhibits positive deviation from ideality, both in the activities of cobalt and gold, and in the enthalpy and excess entropy of mixing. The results agree with previous measurements using a Knudsen cell - mass spectrometer technique, but differ from those reported for a gas equilibration method. The data have been used to calculate the activity coefficient of cobalt oxide in silica saturated iron silicate slags and to express the solubility of cobalt in such slags as a function of cobalt activity and oxygen pressure.

Jan 1, 1984

By Woodcock J. T, Millett R. N

It was shown that manganese dioxide could be used as an oxidant in acid thiourea leaching of a gold ore. Manganese dioxide could generate high redox potentials and was as effective as hydrogen peroxide in the leaching process. Results obtained under closely controlled leaching conditions confirmed that high redox potentials enabled faster dissolution of gold to be obtained but led to extremely high reagent consumptions (thiourea, acid, and manganese dioxide). Additions of sodium sulphite solution in an attempt to lower thiourea consumption by reducing formamidine disulphide back to thiourea were only marginally successful. Although thio- urea consumption was slightly decreased, the consumption of acid and manganese dioxide was substantially increased and there was no net benefit in using sulphite. Tests in which a single addition of mangan- ese dioxide was made before addition of thiourea minimized overall reagent consumption and gave only a slightly lower dissolution rate of gold. This is a promising technique for further Investigation.

Jan 1, 1987