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By Ya Vladimirov D, Yu Khudin M, Kiebanov A. F

Problems of the creation of an automated cartographic system for environmental condition estimation and forecasting in mining region are discussed in this paper. The Geographic Information System (GIS) ARC/INFO is offered as the platform for such a system. A breadboard model of the system was tested on the example of Kemerovo province (Kuznetsk coal basin), the most ecologically impacted mining region of Russia. As a result parameters of territorial distribution of integrated adverse environmental impact of the industrial enterprises are reviewed. Administrative regions of Kemerovo province were rated according to a degree of environmental pollution. Further, specific weight of various industries in pollution of region is determined.

Jan 1, 1995

By T Ueda an, T Sasaoka, A Yabuki, H Shimada

The basic concept of auger mining is to extract coal beyond the economic limits of surface mining technology by drilling holes of an appropriate diameter size into the exposed seam of the highwall as deep as is technically, economically and operationally feasible. This method of mining is used at the final highwall of typical surface mining operations. This paper describes the auger mining systems and discusses the methods to increase the coal recovery in auger mining from a field trial in Australia.

Jan 1, 2003

By Cousens DR, Benhamou M, French DH

Techniques appropriate to petrographic image analysis are being developed using digitized backscatter electron images of well characterized mineral assemblages obtained from a Cameca scanning electron microprobe. Emphasis is on developing descriptors for size, shape and association of mineral grains as these all convey important information concerning the nature of rocks and the processes that have operated upon them. Processes, for example, that could indicate the proximity of mineralization. For convenience, the work is being carried out on the PDP11/73 host computer of the electron micropt be, although it is recongnized that such a multi-user environment is not appropriate for practical image analysis. The eventual aim is to develop a low-cost microcomputer-based package for quantitative description of mineral textures and rock fabrics as an objective aid to the petrographic analysis of ores and host rocks.

Jan 1, 1989

Geomechanics is one of the more specialised aspects of site supervision on a major tunnell- ing project. The controlled deformation of a rock mass as a result of tunnelling and the knowledge of loading of temporary and permanent underground supports are important for safe, economic construction. These basic parameters depend on the construction method and sequence and the geological conditions through which a tunnel is driven. Thus geomechanical monitoring during the construction phase provides feedback to a design team and allows any revisions to a design to cater for local conditions not revealed by earlier investigations. Detailed geological mapping is an integral part of geomechanics in the construction phase. It serves as a monitor on pre construction predictions and also forms part of the as- constructed record. If conventional excavation-techniques are adopted, geomechanics can provide a service of blast' vibration monitoring of surface structures in urban areas.

Jan 1, 1976

By Adams DG

At Cook Colliery a combination of main injection of the face coal, and mining into the floor has proved successful for the recovery of faceline falls.The strategy for preventing falls relies upon a conventional method of longwalling. improved geotechnical predictions, and continuous assessment of strata conditions. Different categories of faceline stability are recognised and an operating procedure has been developed for each category.

Jan 1, 1991

By Pollard D, Meadows N

The presence of impurities which are electropositive to zinc in acid zinc electrolyte causes changes to deposit morphology and reduced current efficiency. Glue may be added to control some impurity effects, but assaying for animal glue concentration is difficult and seldom done. Measurement of the activation overpotential for zinc deposition by cyclic voltammetry is used in some plants to monitor electrolyte quality and control glue additions.The deposit morphology and current efficiency of zinc deposition from commercial electrolyte were investigated for various glue additions in the presence of increased levels of antimony. Cyclic voltammetry was investigated as a method of optimising glue additions in the presence of antimony.Scanning electron rnicroscopy showed deposits characteristic of the impurity element present and the glue addition rate. Cyclic voltarnmetry measurements showed some correlation between current efficiency and activation polarisation potential. The importance of using tankhouse electrolytes where results are to be related to tankhouse operation was noted.

Jan 1, 1988

By A Domanti, C Jewkes

This paper describes the design and constructability issues investigated in the selection of a trenchless solution in comparison to trenched construction options as part of a scoping study for the augmentation of the existing Bulimba Creek Trunk Sewer in Brisbane. Initial work involved the planning of alignment options vis-a-vis ground geology, geotechnical conditions, location and depth of shafts considering potential construction technology, flotation and stability of the tunnel, availability of construction sites and the influence of construction works on neighbourhood properties and the immediate environment. Two design pipe sizes, DN1200 and DN1500, were considered, and factors including jacking forces, specification of product pipes, pipe joints, pipe jacking methods and the associated impacts of ground settlement were carried out. Of particular interest was research on suitable lubricating fluids with the potential to minimise jacking forces and maximise the length of pipeline between launch and reception shafts.

Jan 1, 2008

Electrochemical investigations of the flotation of sulphide minerals are re- viewed. Flotation with thiol collectors is interpreted in terms of a "mixed poten- tial" model in which the process leading to hydrophobicity is the anodic oxidation of the collector at the mineral surface and this is driven by the cathodic reduc- tion of oxygen. Electrochemical studies have identified the products of anodic oxidation as chemisorbed collector, metal collector compounds, and dithiolates; the products formed in each situation depend on the collector used, the mineral under study, and the pretreatment of the mineral surface. Investigations on galena, pyrite, and chalcocite are discussed. Electrochemical and x-ray photoelectron spectroscopic studies have been used to determine the products of surface oxi- dation of sulphide minerals in order to elucidate the mechanism of collectorless flotation. The mixed potential mechanism allows consideration to be made of the ways in which flotation of sulphides with thiols can be inhibited. Examples of depressant action are presented. The relevance of electrochemical investi- gations to practical flotation is Discussed.

Jan 1, 1984

By McManus D

Situations where in-pit bench stripping methods are favourable are introduced. Examples from Peak Downs Mine are used as a guide to the range of methods available.A number of geological and geotechnical conditions adverse to successful in-pit bench stripping are described. In all cases bench, floor, and/or final lowwall instability can develop and compromise the economics of extraction.

Jan 1, 1992

By Parkes DB

The excavation of sandstone of generally medium strength for the Liverpool Link Line by Dosco Mark 2A Roadheaders has demonstrated the versatility and good performance of road- headers in suitable rock formations. A description is given of the strata traversed by the tunnels together with descriptions of equipment and crews, excavation sequences, operating difficulties and the results achiev- ed. In addition tunnel construction is des- cribed for a difficult section where there was only O.Sm clearance between invert and a four lane vehicular tunnel below, and O.5m clearance between tunnel crown and a century old sewer above.

Jan 1, 1976

Pulverised coal firing was pioneered in the cement industry prior to the turn of the century. Ash from the coal is absorbed into the mix in the kiln and replaces secondary materials. With high purity limestone coal with high ash content can be used. Fuel cost is a major part of the total manufacturing cost. Cement plants are thus quick to respond to fuel price changes and will use low grade fuels if there is a price advantage. Combustion conditions in a cement kiln differ markedly from a boiler. Flame length is determined by air/fuel mixing but because of fixed secondary air conditions this depends on primary air momentum. Volatile content has some effect on flame length but this can be offset by coal fineness. Much of the heat for cement production is for limestone calcination which is a low grade energy requirement. By allowing long residence time in separate direct fired vessels which then feed the high temperature kiln the energy of materials such as oil shale, tyres and lump lignite can be utilised.

Jan 1, 1987

By B Bendtsen, L McQueen

The use of shotcrete as an efficient means of both temporary and permanent ground support has continued to grow over the last 30 years, with its use underground now commonplace around the world. However, the development of analytical design methods has lagged advances in material and application technologies. Historically, part of the reason for this was a lack of understanding of how shotcrete linings actually worked. Considerable progress has been made in this area in recent years and this paper attempts to summarise the current state of practice with respect to shotcrete lining design. It then concludes by summarising areas where the authors consider future research and development is still required.

Jan 1, 2008

By Scaife PH, Cripps Clark J, Cameron DB

Tuyere coke samples have been taken through the tuyere openings of B.H.P. International Blast Furnaces since 1978 with Whyalla No. 2 Blast Furnace taking samples on a regular basis since 1982. The degradation of coke during it's passage through the Blast Furnace can be measured and the relationships between these data, feed coke data and blast furnace operating data demonstrated. Tuyere coke sampling has been useful in revealing misleading external coke testing results and is still the method to monitor directly the performance of coke within the Blast Furnace.

Jan 1, 1987

By Weber D, Knox PR

The criteria developed for the Argyle Diamond Mine process plant control system are reviewed. The control system installed is described along with a discussion of the method of implementation adopted. The control system was extensively tested prior to instal- lation at site. This approach led to signi- ficant time savings during plant commissioning and facilitated rapid escalation of plant production. The control system has performed satisfactorily with a high level of operator acceptance and basically satisfies the criteria Developed.

Jan 1, 1986

By Kerkhoff G, Wood J

The maximum gas emission into underground workings can be predicted by the use of established methods which have world wide recognition. Changes in gas emission and the influence of the gas and geological environments during longwall mining at Pacific Colliery, were found.to be a typical. The relationship between longwall mining and gassy conditions is found to vary from the European experience because of the different mining and geological conditions encountered, and the higher productivity achieved, by single longwall panels in Australia.

Jan 1, 1988

By Loo R

The Paper discusses the size and extent of in-pit dust suppression problems created by iron ore mining in the Pilbara region of Western Australia. Dust problems associated with drilling, loading, hauling and tipping are discussed indicating the large quantities of water which can be applied for dust control and attempts that have been made to rationalise this water usage to obtain maximum benefits from the applied water. The magnitude of the problem and the quantities of water involved can be appreciated when one realises that 275 000 tonnes of rock are moved on Mt. Whaleback each day and that there are 40 km of haulroad within the open pit. Initially dust suppression was limited to the spraying of haulroads by large water tankers. Now dust suppression is practiced during drilling and after blasting, wind blown dust is reduced by application, using water cannons,of large quantities of water to floor stocks prior to loading operations as well as by the installation of 16 km of automatically controlled fixed sprinkler reticulation on the main semi-permanent haulroads. The methods used to assess the water requirements for in-pit dust suppression are discussed and the extensive development testing used to evolve the present installations are 1. Environmental Superintendent Mt. Newman Mining Co. Pty. Ltd. Newman, W.A. 2. Chartered Consulting Engineer, Perth, W.A.

Jan 1, 1979

In presenting size analysis data, one has the choice of various graphical techniques; each no doubt has been developed to highlight a particular aspect of the data. A frequency size distribution plot is used quite extensively to illustrate the importance of the finer size particles in iron ore granulation. However, the basis for such a plot is often not appreciated. As a result, cases of incorrect use can be cited. The aim of this paper is to extend the work of Alien (1981) and to provide, using examples and figures, a basic understanding of the implications of the various size distributions. A simplified method of presenting sizing data on a linear scale graph paper is presented and recommended. This involves a simple construction of a histogram of mass fraction versus particle size (in geometric progression).

Jan 1, 1992

Infrastructure is defined as all those parts of a mining development which are not directly concerned with mining and mineral processing. Infrastructure is of significant and growing importance in the overall develop- ment of mines, and the costs could be critical in determining the viability of a project. Prior to_project authorisation, feasibility studies are required, often in considerable detail, to determine costs with adequate reliability. It is necessary that the Engineer should be adequately briefed for carrying out these studies and that good liaison and communication with the Owner be maintained. Methods, costs, order of accuracy, and some special requirements of these studies are discussed. After project authorisation, rapid im- plementation of the proposals is generally desired. A suggested organisation and method for this implementation is presented and dis- cussed. Comments on fees, and particular points in the relationship between Owner and Consulting Engineer are given. Particular reference is made to differences in conditions compared with public works projects. Realistic attitudes of mind towards environmental matters, industrial relations, and contractual relationships are advocated.

Jan 1, 1974

By Inoue T, Takahashi N

To construct the accessing railroad line to the northern portal of Seikan Undersea Tunnel, nine tunnels amounting 7.4km in their total length were excavated through soft mudstones of young- er tertiary era with use of smaller-sized mechanic al excavators. Rocks were classified in four classes to which the tunnel support was designed respectively. Of several combinations of driving equipments stu- died comparatively, the method using the mechani- cal excavators was estimated to be the best choi- ce. The efficiency of the excavator was traced in every construction section and the data colle- cted was reviewed numerically. The result showed that the efficiency of the excavator dropped wh- ere the rocks were as hard as over 200kg/crif for compressive strength. And a few technigues in tunnelling i.e. contr- olling dusts in shotcreting, lattice arch, evaluati- ng measured deformations were tested and review- ed too.

Jan 1, 1987

By Grace NC, Lightfoot BW

Small scale trials of the smelting of a copper concentrate in the Sirosmelt submerged lance reactor are described. Pellets of concentrate were dropped into the reactor while injecting air-rich mixtures of oil and air through a lance into a bath of matte overlain by slag. This produced a discardable slag and a matte which was converted in sequential stages in the same reactor to white metal and blister copper. Difficulties were encountered in determining the end points of the converting stages but control techniques were developed to allow successful operations producing blister copper. Deportments of minor constituents of the concentrate to slag, matte,metal and fume for the three stages are reported and possible applications are Discussed.

Jan 1, 1980