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By Gochin RJ

This paper focuses on measures of the economic significance of mineral exploitation and processing activities, such as beneficiation, refining and smelting. Empirical measures are suggested to quantify the relevance of the degree processing within a nation's mineral industry. The most useful, based on the input-output econometric framework, are used to establish the magnitude of links between the mineral industry and its satellite activities and for the appraisal of large, non-marginal projects. The input-output impact analysis is refined to allow for country specific behaviour and synthetic indices for the appraisal of investments in the mineral sector are developed. These indices are further improved with the introduction of shadow prices to incorporate socio-economic issues. They are useful to direct mineral policy decisions and several investments towards the most promising objectives for national goals. Finally traditional methods for the appraisal of small scale, marginal, mineral projects are assessed where local impact and regional development issues are more relevant than national ones.

Jan 1, 1993

The production of 100,000 tonnes per year of synthetic rutile from the processing of ilmenite, coal and copperas (iron sulphate) produces 200 cubic metres per hour of effluent water. A 2.0 hectare biological filter, comprising natural and man- made wetlands, has been built into the last stage of the effluent water treatment system. It is an area of shallow water (

Jan 1, 1988

By Callaghan T

The Henty Gold Mine is located approximately 30 km north of Queenstown, at the head waters of the Henty River on the west coast of Tasmania at 41¦50'S, 145¦40'E on the Queenstown (SK 55-5) 1:250 000 and Sophia (8014) 1:100 000 map sheets (Figure 1). The mine is accessed from Queenstown along the A10 Highway and Anthony's Road. The town of Queenstown is located 260 km north west of Hobart on the A10 Highway, and

Jan 1, 1997

Most orebodies have one or more boundaries which are gradational, where the decision to stop mining is based on an economic cut-off. To maximise profit, this cut-off grade must be chosen correctly. It is necessary to review cut-off grades regularly, as the optimum cut-off grade changes with time, and major changes are hard to implement in a working mine without disruption to production schedules.Whenever a cut-off grade is used, there will be errors in its application caused by errors in the estimation of block grade. These can be minimised by stringent quality control in sampling and by the use of kriging, which attempts to minimise the absolute errors in grade estimation. The kriging method used should produce the most accurate estimates of marginal grade blocks - this will not necessarily be the technique that gives the best overall prediction of head grades.

Jan 1, 1993

By K Paki, K Parker, J F. Dupont

The Mount Charlotte grinding circuit at KCGMÆs Fimiston mill was recently equipped with three 650 mm CAVEX cyclones in order to improve the overflow P80, reduce the fines bypass to the underflow and improve the underflow density/recovery of water to the overflow. After the first two sets of surveys were conducted air core boosters (ACBs) were installed on the 650 mm CAVEX cyclones in an attempt to further increase their performance. JKTech was approached to assist with the examination of the data obtained from the surveys; this data was intensively modelled to determine, to a high degree of confidence, the impact the changes to the cyclones had on the classification and the benefits to the plant. This paper outlines the outcomes of the trial and the methods used to determine those outcomes.

Jan 1, 2007

By M Denton, M Rheinlander, S Mundell, M Broadgate

The manufacturing industry reinvented its approach to the manufacturing process by managing and measuring it end-to-end. This improved returns on production assets, improved information quality and reduced delivery time, resulting in larger net profits through cost reduction and improved cash flow. Today this approach is standard in the manufacturing industry. Resource development has many requirements in common with the manufacturing production line. These include: control of the various steps, transparency of the state of the process to various levels of the organisation and the overall efficiency with which the process is executed. The authors argue that the introduction of manufacturing execution systems (MES) concepts and technologies to resource development processes will lead to similar improvements in control, transparency and efficiency and could improve profitability and enable staff to work more effectively and make better decisions.

Jan 1, 2009

By Stitt P. H

This paper provides a brief historical review of the invention of the spiral separator and its adoption into Australian metallurgical practice. The purpose of the review is to demonstrate that spiral development to date appears to have been a largely empirical process, and that the cur- rent resurgence of interest in the spiral, especially in the coal industry, warrants an increased fundamental research effort. Current research work concentrating on empirical modelling is outlined, while some preliminary experimental results of a more fundamental nature are presented and some research of other disciplines interested in particle transport introduced in order to stimulate further work and discussion.

Jan 1, 1988

By Fourney W. L, Dick R. D

Tests were conducted in plexiglass and Rockite models to determine if crater blasting could be improved by changes in charge geometry or by alterations to the borehole. Circumferential grooves were placed at various locations in the borehole in an attempt to control the initiation site of the crater. Grooves located at or above the top of the cylindrical charge had no effect on the resulting crater. Grooves placed too low in the borehole were successful in controlling the initiation site but the growth of the fracture system was not sufficient to reach the upper surface. Grooves located at a height of two thirds of the charge length were quite successful in that resulting craters were bigger by at least a factor of six than the normal crater. Testing was conducted in Rockite models to investigate charge geometry. Spherical charges in ungrooved boreholes resulted in crater sizes that were three times larger than those caused by cylindrical charges.

Jan 1, 1990

By P Knights, M S. Kizil

Truck/shovel operations constitute 50 - 60 per cent of the cost of open pit mining operations. Mining companies, therefore, are constantly seeking to close the gap between actual truck/shovel productive capacity and maximum potential truck/shovel capacity. This paper analyses the performance of a mixed truck/shovel fleet in an open cut coal mine in Australia. It analyses operating delays, and proposes a novel graphical means of determining truck-limited or shovel-limited operations. A goal seeking algorithm is advanced in order to maximise truck/shovel match factors (MF) and hence optimise fleet productivity.

Sep 26, 2011

Cut and fillstoping using hydraulically placed mill tailings has become an essential feature of stoping operations in Kalgoorlie. ' Approximately 30 per cent of the total production is currently mined by this method. Fill is prepared by thickening or cycloning and is gravitated or pumped underground. The average pulp density is 70 per cent solids by weight, Recent cost reducing innovations are the use of steel passes, corrugated iron manways, polythene film sealing, and the replacing of vertical cement lined pipes with boreholes. TTTTTI rvr T Trim r l1TT

Jan 1, 1964

The problems arising in the excavation of hard rocks with the use of mechanical tools consist chiefly in a slow advance rate accompanied by an intensive wear due to the toughness and abrasiveness of the rock. In order to allow the further extension of mechanical excavation beyond the limits of the presently available technology, the assistance of waterjet aiming at improving the performance of the equipment while reducing the wear rate of the tools, has been recognised as one of the most interesting technical solutions. The paper illustrates the improvement of the performance of both disk cutters and picks obtained with the waterjet assistance at the Waterjet Laboratory of the University of Cagliari on a medium-hard rock.

Dec 6, 2010

By Naik J. S G

The plant practice plays an important role in production and productivity. Men, material and machinery have to be judicially utilised to achieve maximum output with minimum cost. Improvements in technology should be incorporated at an appropriate time and place. The personnel concerned should be properly trained and motivated to receive the changes in machinery and technology. Strict adherence to prescribed parameters, optimum utilisation of man, machinery and operating supplies help in the smooth functioning of the plant and in achieving maximum gains.

Jan 1, 1992

The relationship between the permeability of coal to a mixture of methane and carbon dioxide, and the permeability to methane and carbon dioxide separately is described in this paper, along with the analysis of the differences in permeabilities of coal to methane and carbon dioxide.

Jan 1, 1989

By Piga P, Sammarco O

Ventilation and the environmental climate in the Campiano mine is the subject of this re- search. The mine is located in Southern Tuscany (Central Italy), a region where geothermal gra- dients are very high (three times the average gradient of the earth). The research produced interesting indications as to the influence of surface climatic conditions on the environmental parameters inside the mine. A close correlation has been found between dry-bulb temperature and humidity ratio of the air in the mine for dif- ferent metereological conditions and for differ- ent mass flow rate values. Variations in air enthalpy, caused only by the heat exchange with the rock walls during the flowing of the air through the mine, depends on the surface temperature values. Statistical analyses have been used to ex- press air enthalpy variations on surface tempe- ratures, on the variations of the humidity ratio that the air undergoes inside the mine and on the mass flora rate. The application in practice of the results will permit the identification of correct mea- sures to be adopted so that optimal microcli- matic conditions are produced in the mine.

Jan 1, 1986

The Beaconsfield gold mine processing plant is a complex operation and utilises crushing, grinding, gravity gold concentration, sulfide flotation, bacterial oxidation, cyanidation and zinc cementation to recover gold from the partially refractory ore. This paper discusses the challenges, developments and advancements throughout the processing plant since start up, which have culminated in a 25 per cent increase in the mill throughput over the nameplate design and a concomitant gold recovery increase from 75 to 92 per cent. The improvements have been attained via advancements in mechanical integrity, metallurgical review, process control and operator training, resulting in the current operation producing over 630 000 ounces of gold to date.

Jan 1, 2007

By Ono K, Oishi T

Electrochemical determination of the oxy- gen partial pressure in the Fe-0-SiO 2 ternary systems saturated with solid silica was done by measuring the activity of oxygen in a silver bath in equilibrium with the molten slags using zirconia solid electrolyte galvanic cells. From the data obtained, the activity ~Faii.st composition relations were calculated

Jan 1, 1980

By P A. Gow, J L. Walshe, G J. Masterman

The Eocene-Oligocene porphyry belt of northern Chile contains the worldÆs largest accumulation of porphyry-related copper metal. Conflicting models exist regarding the relative importance of strike-slip and reverse faulting during the emplacement of the porphyry and epithermal systems, based on regional studies and also from work at the Chuquicamata deposit. In contrast, at the Collahuasi district, high sulfidation state copper-silver mineralisation was superimposed into the core of the Rosario copper-molybdenum porphyry deposits along normal faults during gravitational collapse of the Domeyko Cordillera. Exhumation of the porphyry environment occurred rapidly during this event, allowing near-surface epithermal mineralisation (<200 m paleodepth) to be juxtaposed into the potassic altered core of the porphyry deposit (estimated depth of formation: 1300 m) in the space of approximately one million years. Mass wasting after major episodes of tectonic uplift provides an effective method of hypogene upgrading of porphyry ores by high sulfidation mineralisation.

Jan 1, 2005

The sedimentery basins of this region developed in the collision zone of the Pacific Ocean plate and the continent. Stresses were transmitted thorough wedge-like lithospheric blocks, such as the Okotsk Sea, East Kamchatka, Aleutian and 2 other smaller blocks. Compression and inversion were more active at the boundaries: P ; P3 ; N1 ; and Z N in places. ? K2 P2 P3 N2 Tension, rifting and the increase in the rate of sedimentation were marked in '-2 , P3, Ni - N2, and also N2 - Q in places. Structural plan changes of the sedimentary basins and possible oil, gas and fluid migration occurred more actively 2 3 1 2 at the boundaries: ; P3 . N? , N1 N1 NZ N2 P2 P3 1 N1 'N 2 N3 Ni 1 1

Jan 1, 1995

The discovery of economic uranium miner alisation in unique geological conditions at Yeelirrie, 700 km NNE of Perth, presented Western Mining Corporation Limited with a num- ber of sampling and evaluation problems. Carn- otite mineralisation occurred in a porous cal- crete-clay lithology in close proximity to the water table; background information on such a deposit was non-existent and sampling in these conditions could be difficult. The deposit was sampled initially by aug- er drilling with X-ray fluorescence analysis of drill cuttings, followed by reverse circulation and diamond drilling with analyses by X-ray fluorescence and gamma logging of the holes. Two costeans provided lithological and grade distribution data and mining experience in the deposit. Spoil from the costeans was stockpiled according to location in the first costean and according to location and grade in the second costean. Samples from the various stockpiles were analysed by X-ray fluorescence. No. 1 costean was extensively sampled by channel sampling of the walls and by pit sampling of the floor of the benches of the costean by back hoe. No. 2 costean was sampled by Geiger counters mounted in T-probes and by the gamma logging of auger holes to establish the valid- ity of the T-probe results. Samples were taken

Jan 1, 1976

By Miyashita T, Yamamoto R, Kishimoto s

Following considerations of the effect of furnace size on pressure loss, pressure loss in front of tuyeres, gas flow in the lower parts of the furnace, the distribution of the burden and the gas flow in large blast furnaces is examined with particular reference to the burden distribution at the throat and the gas flow at high production rates. Improvement of gas flow is related to application of super-high top pressure and the use of moveable armour. A brief description of the NKK type moveable armour is given and its use in controlling the gas flow outlined. The operating results under controlled gas flow show an increase in production of Fukuyama No. 5 BF from 9,200 tpd to 11,000 tpd with a decrease in the fuel rate from 490 kg/thm to 460 kg/thm.

Jan 1, 1975