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Ok Tedi Mining Limited has recently completed the first phase of a trial to compare the performance of D26B Krebs cyclones in different configurations to the new Warman 650 mm CAVEX cyclones. From 1992, rougher flotation feed size has increased from the target d80 grind size of 150 ¦m with increasing SAG mill throughput. At high SAG mill throughput, operators have difficulty maintaining the target cyclone feed pressure and must increase the cyclone feed density, thus resulting in a coarsening of the cyclone split. Warman International have developed the CAVEX high capacity cyclone. The new CAVEX cyclones, when compared to the Krebs units appear to:produce a measurable increase in volumetric flow for the same pressure drop; maintain or decrease the proportion of coarse particles reporting to overflow; and lower the overflow density. In all plant trials to-date, the CAVEX cyclones appear to be superior to the standard Ok Tedi Krebs cyclones. Further testwork is planned to evaluate modified Krebs cyclones (with recent design improvements) against the CAVEX cyclones.

Jan 1, 2000

By Kukla G. T

A Seam deposit User oriented Mine Planning System (SUMPS) was developed by The Broken Hill Proprietary Company Limited (BHP) at its head office in Melbourne. It is one of the computer mine planning systems developed by the Corporate Data Processing (CDP) section of BHP. To date it has been employed in the feasibility study of four coal prospects for the BHP Group, including Gregory in central Queensland - Ham and Van Hoorn (1978). It was also used in detailed short term mine planning for Gregory. A recent application was in the feasibility study of Saxonvale, a multi seam coal deposit in New South Wales with seams up to 20 m thick. The other two applications of SUMPS were also on thick multi seam coal deposits. Development of programs for the underground sub-section of SUMPS is continuing. SUMPS was developed and implemented on mini computers with graphics and plotting peripherals. The company's philosophy towards computing is one of centralized development and project planning, with transfer of hardware and software to site once the mine becomes Operational.

Jan 1, 1980

The mIning operations of Bougainville Copper Pty. Limited are located at Panguna on the Island of Bougainville which is part of the Territory of Papua and New Guinea.C.R.A. Exploration Pty. Limited first established mineralization in the Panguna area in 1964. Exploration work since then has established ore reserves estimated to be 900,000,000 long tons of ore assaying 0·48 per cent copper and 0·36 dwt/ton gold. An economic feasibility study completed in July, 1969 enabled a decision to be made to proceed with a major mining operation. The ore will be mined by open cut methods and will be treated in a conventional concentrator with a nominal capacity of 90,000 short tons/day. The concentrate will be pnmped as a slurry through a 16 mile long pipeline to a port established on the east coast where it will be filtered and dried ready for export. Other supporting facilities for the mine include two towns, a 135 MW steam power station, and access roads.

Jan 1, 1971

By Gibson I, Somerville J

Three main confined aquifers occur in interseam sediments beneath the planned excavation for the Loy Yang Brown Coal Open Cut. Sub-artesian groundwater pressures occur in all aquifers necessitating dewatering to prevent excessive seepage and depressurisation to prevent heaving of the open cut floor and batter instability. Reduction of water pressures in coal joints is also required to maintain coal face stability. This paper describes the depressurization and dewatering strategies, investigation for and installation of pump bores and groundwater observation bores. Approximately 5000m of drilling is carried out annually for dewatering at Loy Yang and both cable tool and rotary flush drilling methods are utilized. The cabletool method is used to obtain accurate samples for laboratory analysis, whereas rotary flush methods are used for speed and for installation of the larger diameter pumping bores. A method of re-establishing pump bores after partial excavation during mine development has been successfully developed with large cost savings. Trials are also being conducted with pre-collaring of deep bores with rotary methods then sampling the aquifer strata with a cable tool rig.

Jan 1, 1988

By D J. Clark, S Hewson, T Li

Cadia Hill Pit is a gold copper porphyry deposit hosted in monzonite. The pit slope design is primarily based on structural controls related to faults and shears with largely massive rock masses between the structures. The slope design attempts to achieve an optimum configuration at a bench to overall scale, considering economics and safety implications against the geotechnical and structural conditions. To date the slopes have been mined at interramp angles of up to 60¦ over heights of 120 m. Limited slope and batter failures that have occurred are structurally controlled and occur rapidly. The pit-mining schedule requires concurrent mining of part of the final pit walls and the progressive interim cutbacks. Engineering and operational solutions to hazard reduction and risk management issues have been implemented wherever viable to æengineerÆ out the hazard and mitigate the risks. However, comprehensive management plans and operating procedures have also played a vital role. This paper details the management plan and the operating procedures that have been developed and implemented to mitigate the risks associated with rock falls.

Jan 1, 2003

By B G. Blacka, O Salisbury, K W. Mills, R G. Jeffrey

Whitehaven Coal Limited operates an underground longwall mine near Narrabri, New South Wales. The mining horizon in the Hoskissons Seam is overlain by a 16–20 m thick unit known as the Digby Conglomerate, a unit that is sufficiently massive to have potential to cause a windblast during first caving at the start of each longwall panel and periodic weighting throughout the panel. A program of hydraulic fracturing has been successfully used to precondition the conglomerate strata to increase its caveability at the start of each panel. This paper presents a system of temperature monitoring that was used successfully to measure hydraulic fractures at Whitehaven confirming their rate of growth, orientation and interaction with previously placed hydraulic fractures.CITATION:Mills, K W, Blacka, B G, Jeffrey, R G and Salisbury, O, 2014. Temperature monitoring of hydraulic fractures used for preconditioning massive conglomerate strata to reduce windblast, in Proceedings AusRock 2014: Third Australasian Ground Control in Mining Conference , pp 189–194 (The Australasian Institute of Mining and Metallurgy: Melbourne).

Nov 5, 2014

By J M. Parr, C J. Yeats

Discovered in 1991 by combined plume detection and bottom-tow photography (Binns and Scott, 1993) and for some years thereafter the highest tenor mineral occurrence known on the ocean floor, the PACMANUS hydrothermal field has since been surveyed and sampled in great detail by CSIRO and international research agencies (Binns et al, 1995; Auzende, Urabe and Scientific Party, 1996; Binns et al, 2002; Tivey et al, 2006). Since 2005 commercial surveys employing deep-tow geophysical packages and remotely-operated vehicles (ROVs) have been conducted by Nautilus Minerals Inc and partners within Papua New Guinea-granted offshore exploration licenses (Nautilus Minerals Inc, 2008). Two academic drilling programs have been conducted, one under the international Ocean Drilling Program (ODP) directed at deep structure (Shipboard Scientific Party, 2002; Binns, Barriga and Miller, 2007), and one using a 5 m capable seafloor diamond drill to investigate the immediate subsurface at one site (Petersen et al, 2005). An EXTENDED ABSTRACT is available for download. A full-length paper was not prepared for this presentation.

Jan 1, 2008

By J Välivaara

The mining industry will face numerous challenges over the next 10–15 years as new deposits are likely to be more remote and lower grade and existing deposits will be mined deeper. As a result, mines and mining contractors operating in deep-mine conditions will need to focus on the quality of drilling and blasting to minimise unnecessary waste rock excavation to keep costs at an acceptable level. In addition, increased demand for improved safety and operator ergonomics will set greater demands on original equipment manufacturers of mining equipment. Finally, difficulties finding a skilled and experienced workforce, particularly in remote mine locations, have already negatively impacted mines’ ability to achieve high productivity and low operating costs.This paper introduces techniques and shares practical experiences in increasing productivity and reducing the costs of excavation in underground face drilling. The paper uses Sandvik’s new DD422i automated mining jumbo as an example of the type of equipment needed to deliver the features and corresponding benefits for future mine development. Case studies using this equipment are presented to illustrate the points made in this paper.CITATION:Välivaara, J, 2016. Automated drilling features for improving productivity and reducing costs in underground development, in Proceedings Seventh International Conference and Exhibition on Mass Mining (MassMin 2016), pp 723–730 (The Australasian Institute of Mining and Metallurgy: Melbourne).

May 9, 2016

An efficient filtration plant can be designed only from an adequate knowledge of the filtration characteristics of the material to be handled; if these characteristics can be expressed in the form of an equation the work of design is simplified immensely. The literature of the subject contains numerous equations which have been developed by various workers to express their results, usually obtained from a 'Very limited class of material, and from moderately thick pulps. Such expressions have been found quite unsuited for use in the case of thin, very free filtering pulps.In 1926, Underwood put forward an equation having a general for m, and which, he was able to show, provided a satisfactory expression of the data obtained and published by a large number of earlier workers. This equation has been found a very satisfactory and useful tool for the study of a variety of filtration problems. As thel basis of the equation is of assistance to the understanding of subsequent discussion, a brief account of Underwood's derivation is given here.UNDERWOOD's FILTRATION FORMULAEThe following symbols are used:

Jan 1, 1932

By Jagger N. D

Lead residue from the Zinc Leach Plant at Pasminco's Port Pirie Lead Smelter was previously filtered on a vacuum drum filter and further dried in a gas fired rotary kiln prior to stockpiling and transport to the Sinter Plant. This process involved several materials handling stages, recycled significant amounts of zinc and often resulted in poor environmental conditions. These problems have been overcome by pumping the thickened leach residue approximately 450m to the Sinter Plant where it is filtered in a Larox Automatic Pressure Filter. The filter cake is discharged onto a conveyor belt, held in a storage hopper and then fed directly to the main sinter plant feed stream. Filtrate is returned to the process for additional zinc recovery. The laboratory and pilot plant filtration results are briefly discussed and compared with the operating plant data. The filter installation and ancillaries are described in detail along with the commissioning, operating and maintenance experience over the past 4 years. This installation has overcome the environmental and materials handling problems and resulted in annual savings of approximately $1 million.

Jan 1, 1989

The implementation of the Mining Further Amendment) Act, 1970, and later the Coal Mining Act, 1973, placed a requirement on the Department of Mines to accept an initiative in relation to coal exploration and coal mine development which does not apply in the case of other minerals. It is necessary to consider the exploration of the total coal resources of the State when considering exploration rather than one individual basin or deposit. If the level of knowledge of the coal resources in these basins is considered in relation to their potential for development it is possible to allocate broad scale priorities to their assessment. Due to the enormity of the task which involves a conservative estimate of in excess of 400 000 m of drilling to reach a broad reconnaissance level of understanding the involvement of industry with the Department in the exploration programme is necessary. The development of the coal deposits by mining operations must give consideration to a number of constraints apart from the simple availability of the resources. Principal among these are aspects

Jan 1, 1976

German coal mining suffers from rock temperatures up to 600C which are the same as in South Africa at 3000 - 4000 m of depth. Therefore cooling plants have increased in the last decade and today a cooling power of nearly 200 MW is installed in the total Ruhr District. Cooling a mine is a little bit different from cooling a bottle of beer in a refrigerator in the kitchen because the heat taken from the bottle of beer is delivered to the kitchen some centimetres away; in mining the cooling-problem is more difficult: here the bottle of beer corresponds to the airflow at the coal face and the kitchen to the surface, So it is necessary to transport the heat or the "coldness" a long distance. In the address by Ieuan Morris some systems for transporting heat from the coalface to the evaporator of the cooling machine and further from the condenser of the machine to a return airflow were described. The following is a short idea of the way this problem is treated in Germany.

Jan 1, 1983

By Sterns UJ, Weller KR

Grinding to sizes less than 80 per cent passing 20 ¦m in both primary and regrind circuits is becoming increasingly important in processing metalliferous ores, as many of the remaining orebodies are very fine-grained and refractory. The process of very fine grinding, however, is expensive, and neither the performance nor the design criteria are well understood. This paper presents some findings from a collaborative research program, one of the objectives of which has been to better understand and improve the performance of very fine grinding circuits. Data from surveys of an industrial tower mill grinding circuit are reviewed and analysed using the population balance models of the CS]RO and 7KMRC. The performance of both models with regard to changes in feed size distribution, ball load and feedrate is assessed using these data. From comparisons between pilot and full scale tower mill operation a prototype scaling methodology is also presented which shows promise in allowing the models to be used to predict the effect of changes in mill Design.

Jan 1, 1993

By Richards AG

The stimulus of major capital expenditure in establishing open cut coal mining operations in the Hunter Valley led Coal & Allied Industries to look to a computer based information system as a tool to assist mine management in day to day operating decisions, as well as to provide a base of comparative data to help in long term equipment procurement decisions. The mine information system was conceived as an integrated set of three subsystems; costing, production recording, and maintenance. The maintenance management features of the system are closely keyed to a policy of preventive maintenance and maintenance costing based on user specified parameters. Central to this policy is the maintenance work order, which may be created and updated directly via interactive procedures at visual display terminals. The, system was designed for on-line processing in a multi-mine shared operating environment. Each mine controls its own data capture, and most other processing functions directly from terminals. The system is currently operational on the Combined Group Services Pty Ltd FACOM M150 computer, located in Newcastle, NSW.

Jan 1, 1983

By Vanderberg B

A 3D, PC based computer program is currently under development by Blasting Analysis International, Inc., to analyze the kinetics of full scale blasts with two or more high-speed motion picture cameras. Todays common approach of utilizing only a single camera system can, in some cases, lead to great errors and erroneous conclusions when motion is assumed to be in a predefined plane of motion. CMe phrase, "What you see is what you get, it no longer true in 3D."). This is especially true in blasting environments which exhibit complex and/or predominant structural geology. The 3D system eliminates this problem, and includes automatic corrections for vertical and horizontal camera optic axis orientation, dimensional controls, lens distortion, field set-ups, projection imaging and digitized inputs. The only information required is the surveyed or known coordinates of at least six non coplanar points in the field of view. Motitn from each camera view is then digitized, transformed through a direct linear transformation, and processed with the 3D software, which also automatically time matches the data, even when the high-speed cameras are operated at different speeds. Eleven calibration constants are generated using an overdetermined system of linear equations to output the true 3D coordinates of motion in the time domain. Applications for this 3D approach are not restricted to just analyzing the kinetics of a blast. The system is sufficiently flexible to allow an accurate, quick and economical method of bench face profile analysis, generate muck pile profiles and estimate volumetric calculations. The recording systems for these applications can be common 35mm still photography and/or video equipment. It is envisioned that this system will soon replace expensive laser surveying systems at a fraction of the cost in the near future. It is also an excellent system to accurately quantify drill pattern layouts and the spatial locations of each blasthole. This information is required for generating single hole based synthetic seismograms to accurately predict the vibrational outputs of full scale blasts. In terms of litigation concerning claims resulting from blast induced ground vibrations to structures, the system is proving to be an excellent and economical method of performing pre-blast surveys where differential settlement is suspect.

Jan 1, 1990

By G H. Luttrell

The use of secondary desliming cyclones ahead of froth flotation cells to reject ultrafine (-45 ¦m) particles has become a popular option in the United States for preparing fine coal feeds for froth flotation circuits. In light of this popularity, several experimental studies have been performed at industrial plant sites to develop a better understanding of the impacts of ultrafine desliming on froth cell performance and, ultimately, overall plant performance. These studies included an evaluation of various circuit configurations incorporating different flotation technologies (conventional machines and column cells) as well as different dewatering systems (disc filters, screen-bowl centrifuges, and thermal dryers). The data obtained from these studies indicate that deslime circuits offer several important benefits including lower product ash, reduced product moisture, better froth handling characteristics, and lower capital and operating costs. In addition, case studies conducted as part of this investigation have been used to develop generic guidelines for how deslime circuits may be successfully applied to improve the overall profitability of fine coal flotation circuits for both the metallurgical and steam coal markets.

Jan 1, 2005

The Liddell longwall equipment consists of 118 four leg supports, a shearer and armoured face conveyor of 170mm length. The equipment was supplied to Coal & Allied Operations Pty Limited (Coal and Allied) by Westfalia Australia Pty Limited (Westfalia). The project commenced as a feasibility study in 1983, a proposal was put to the board of directors in March 1984 and a specification distributed. Nine companies tendered for the supply of a longwall face and the supplier was selected from a short list of four companies. At the same time Coal & Allied examined the facilities at Liddell Colliery and decided to upgrade the conveyor belt system to cater for the high production from a longwall face. The surface facilities, transport system, water and electrical supplies to the colliery were also to be upgraded. During the twelve months to December 1985, the colliery was upgraded while the longwall equipment was being manufactured. The manufacturing process involved roof support testing, compatibility testing and finally a build up of 40m of longwall face

Jan 1, 1986

Over the last ten years geological and mining software products have evolved greatly. Software companies developing such products have focussed almost exclusively on the development of technical aspects of the applications, addressing geological, ore reserve estimation and mine planning problems. These specialist applications, and the many other new technologies that are being developed by a myriad of niche developers, are an essential part of todayÆs hi-tech mining operations. Technology is also being used in many other areas to improve the mining process and there is no doubt that tremendous advances are being made in all these fields. Yet there is something missing. The manner in which the technologies are used and implemented has led to the creation of many independent and inefficient æislands of technologyÆ where a variety of products from different vendors are used to address different, but related problems. Problems occur with unreliable information, data duplication, data redundancy and transferring data between applications that may be incompatible or even run on different computer platforms. These problems impede the flow and availability of information and hamper day-to-day decision-making by mine management. A solution to this problem is to take a holistic view of all the various technical applications and incorporate them into a single information technology solution. This solution must encompass all of the information requirements of a mining operation and must provide facilities that address much of the modern thinking about mine management, including strategic mine planning, value management, key performance indicators, and maintenance of a mineral balance sheet. Gemcom is developing an Integrated Resource Asset Management System (IRAMS), which is an enterprise-wide integrated computer system that encompasses various applications typically found at a mining operation. The core component of the system is a common, open, industry standard database that can be shared by many users from each of the different departments at a mine. Around that central repository are the primary applications that provide the mine with information it needs to operate. Ensuring that the information is reliable, accurate, shareable, timely and consistent will eliminate many inefficiencies, and provide significant benefits to mining companies. In turn these benefits will lead to significant improvements in decision-making, productivity and profitability for the operation. The initial version of the IRAMS system is currently being implemented at the De Beers Venetia Mine in South Africa. The system is being built around a core repository using the Microsoft æBack OfficeÆ architecture, and incorporates key technical applications from Gemcom, Whittle, De Beers Technical Team, Wenco and JKTech. The benefits of enterprise-wide systems have long been recognised in the commercial arena and enterprise resource planning (ERP) systems such as SAP, JD Edwards and MIMS are becoming commonplace in the mining industry. The more forward looking software developers and mining companies realise the need for efficient management of the information gathered during the mining process and can see that the concepts used in ERP systems apply equally to the technical applications as they did to commercial applications. The use of IT in the mining industry has expanded tremendously over the last five years as enabling technology and management acceptance has become more prevalent, and there is considerable room for dramatic growth over the next five years. The evolution of geological and mining software has now reached the stage where mines will yield the greatest returns by integrating the applications used in each area of their operations.

Jan 1, 1999

By K Gottliebsen

Many hydrometallurgical and chemical processes produce large amounts of acid waste. This is illustrated by the copper S/X-E/W process used at the Mount Gordon mine in North Queensland, which produces a tank house bleed in the form of a concentrated sulphuric acid stream. The bleed stream is necessary to remove impurities such as iron that decrease the efficiency of the electrowinning process. However, this bleed stream comes at a high financial cost due to large quantities of make up sulphuric acid required as well as the need to neutralise the bleed stream prior to disposal. The present work describes the approach taken to develop a solvent extraction process for the selective recovery of sulphuric acid from copper tank house bleed liquor. The proposed extraction system was investigated using a branched long chain aliphatic tertiary amine tris(2-ethylhexyl)amine (TEHA) as the extractant, Shellsol 2046 as the diluent and octanol as a modifier. Computer simulations were used to determine the optimum operating conditions for the recovery process. It was found that the process was able to selectively recover up to 90 per cent of the sulphuric acid from the copper electrolyte. This is recovered as a pure aqueous acid stream at a concentration of up to 130 g/L that can be recycled back into the tank house circuit or other areas of the process. The raffinate acid concentration was reduced from 180 g/L to as low as 18 g/L, significantly reducing waste disposal and the environmental impact of the copper process. The equilibrium data and simulation results were also compared with an alternative extractant, CYANEXR 923. Finally the efficiency of the TEHA extraction system was investigated on a pilot-scale in a pulsed perforated plate column. This information was used in order to scale the process for an industrial application. The same methodology applied in this case study could be used to provide innovative and cost-effective solutions to waste streams encountered in other hydrometallurgical or chemical processes.

Jan 1, 2000

By A Jafari, N Khalili, M Vahab, P Broumand

This paper presents the implementation of the eXtended Finite Element Method (XFEM) in the general-purpose commercial software package COMSOL Multiphysics for multi-field thermo-hydromechanical problems in discontinuous porous media. To this end, an exclusive enrichment strategy is proposed in compliance with the COMSOL modelling structure. COMSOL modules and physics interfaces are adopted to take account of the relevant physical processes involved in thermo-hydromechanical coupling analysis, namely: the mechanical deformation, fluid flow in porous media and heat transfer. The model preprocessing, level-set-updates, coupling of the relevant physics and postprocessing procedures are performed adopting a coherent utilisation of the COMSOL’s built-in features along with the COMSOL’s LiveLink for MATLAB functions. The capabilities and performance of the proposed approach are investigated by examining several multi-field thermo-hydro-mechanical simulations with reference to the block caving process in mines.

Nov 29, 2022