Search Documents

The Kaldo furnace smelting technique was developed for oxygen steel production by the late Prof. Bo Kalling, Domnarvet, Sweden. Development started in 1948, and production in 1956. Five million tons of steel were produced in TBRC's in 1973. Mainly due to high TBRC maintenance costs, the steel industry now prefers non-rotating converters. In non-ferrous metallurgy, however, qualified new applications of the TBRC technique have been realized or are being considered. Inco, Canada, succeeded to convert nickel matte to metal in the Domnarvet pilot plant in 1959, and have now installed a commercial plant in Copper Cliff. La Metallo-Chimique, Belgium, has pioneered secondary copper smelting and refining in the TBRC, operating plants in Beerse, since 1968, and Alton, U.S.A. Peko-Wallsend Ltd., Tennant Creek, Australia, was faced with the problem of producing saleable blister from concentrates containing 1.5-2.0% Bi. The flash smelting matte, containing 0.2% Bi, could not be refined to an acceptable limit of 0.03% Bi in the blister copper in a Peirce-Smith converter. Tests at Domnarvet indicated that a TBRC would achieve satisfactory bismuth elimina- tion. Two TBRC's were installed in Tennant Creek and operated for 14 months during 1974-75. The problems encountered and how they were over- come are described. Further TBRC applications have been studied in Sweden.

Jan 1, 1976

By Richard L. Fowler

An automatic steering control system was designed, installed and tested on a coal mine shuttle car. The system utilizes sensors and associated signal processing electronics developed under a previous phase of this contract. The automatic steering system performs the routine guidance functions of turning corners and straight-through tramming. The shuttle car driver retains full authority of speed, braking, load and unload functions and at any time may exercise his option with manual override or steering. Steering information is generated from signals derived from the existing Lateral Guidance sensor subsystem, and all operational features of the previously developed open-loop system are retained. Above ground system tests were conducted in a simulated mine constructed of wood panel ribs. Results were in good agreement with prior hybrid computer simulations undertaken to validate the basic control system over a broad range of conditions and to select system parameter values. The automatic steering system was successfully demonstrated in the above ground simulated mine to USBM technical representatives. Designed to meet USBM permissibility requirements, the system is ready for a Phase II underground testing program. Testing in actual underground mine environment is expected to provide additional data regarding recommended performance improvements and implementation techniques.

Jan 1, 1975

By Dale Preece, C. Mick Lownds

Detonation delay timing has been an important aspect of quality rock blasting for decades. Detonators that enable delay timing have improved over the years especially with the recent advent of precision electronic detonators. The positive effects of precision delay timing have been observed repeatedly in the field with improved fragmentation, heave and overall blast control.

Jan 1, 2008

Education and training research is a major component of the Bureau of Mines human factors research program. The goal of human factors research is to enhance human performance for the purpose of improving both safety and the profitability of the minerals industries. This is achieved through the design of mining equipment, work tasks, management procedures, and development of human resources. This proceedings volume presents several new developments that are helping to improve the quality and efficiency of health, safety, and occupational skills training in the mining community. Several papers address the issue of how to teach and assess miner abilities to deal with underground mine emergencies. Other papers examine practical procedures for defining and cost justifying the integration of structured training and other performance improvement strategies to enhance the proficiency of the work system.

Jan 1, 1988

A low grade, refractory ore gold mine with high striping ratio such as at Macraes is always challenged in ways to improve margins. Common practice approaches used at OceanaGold Ltd Macraes are to maximise grade delivery, optimise recovery and reduce unit costs, as well as take any opportunities to incorporate new technologies and implement enhanced commercial strategies.   The Business Improvement (BI) programme was implemented across the Macraes operations in late 2003 and is being rolled-out to all other parts of the business. The core focus of BI at OGL is to: +        increase revenue, +        reduce cost, and +        improve processes.   A dedicated BI team comprising of a manager, team leaders and business analysts were engaged to identify and manage a series of opportunities to reduce operating expenses, optimise capital outlays and generate extra revenue. The Business Improvement Programme, though in its formative phase, has begun a cultural change within the organisation. Many people are starting to challenge the way they do things and are looking for ways to continually improve business performance.   The BI team encompasses individuals from different departments who can offer the diverse skill set necessary to produce intended results. The current team is made up of a BI manager, BI Team Leaders in Mining and Processing and analysts from Mining, Processing, Commercial and Plant Maintenance workgroups. A team member has recently been formally trained as a Six Sigma Black Belt. ] The BIÆs team role is to assist in the establishment of project management processes for each improvement idea. In addition the team will assist in tracking implementation, identifying and unblocking restrictions and limitations as well as setting up metrics to quantify the level of benefit returned and sustained.   From a more strategic point of view, the BI team is advancing the Business Improvement capability of the company by developing long term Communication and Training strategies. These strategies will set the direction of BI initiatives in the years to come to: +        educate the OGL workforce in basic BI techniques, +        assist the OGL workforce in applying basic BI techniques, +        communication the direction of BI in OGL, and +        close the information feedback loop to facilitate transparent communication between the OGL workforce and the BI team.

Jan 1, 2004

By Markku Rytkonen, Shaolong Chen, Ilpo Kylmäkorpi, Hannu Mansikkaviita

Though the Peirce Smith (P-S) converter is a traditional type of furnace, continuous improvement in its mechanical and electrical design is still Kumera's approach. Efforts are made particularly on the following aspects: converter head shape for easy fabrication and structural strengthening, oxidation air swivel joint for low pressure drop and low noise level, wind box for even air distribution to tuyeres, drive unit and its control for reliable and handy operation. These improvements have successfully been applied in recent P-S converter deliveries.

Jan 1, 2009

By P. G. Kovalchik

Overexposure to noise remains a widespread, serious health hazard in the US mining and other industries despite 25 years of regulation. Most categories of illnesses and injuries associated with mining have improved, with the exception of hearing loss. The drilling of rock in a confined work environment contributes to high levels of noise exposure in mining. The National Institute for Occupational Safety and Health (NIOSH) is conducting research to reduce the noise exposures of jackleg drill operators and to prevent additional cases of noise induced hearing loss (NIHL) by developing and evaluating low-cost retrofit noise controls for equipment. This report describes the procedure for the measurement and reporting of noise from portable pneumatic tools such as jackleg drills. The technique used in this research allows for the determination of the source A-weighted sound power levels and the radiation patterns in octave and 1/3 octave bands. Overall sound power level is also determined. This paper also reports the results obtained by using this procedure to evaluate a SECO S215 standard production drill and a CSIR Miningtek prototype rock drill incorporating engineering noise control measures. It was found that by using the manufacture?s recommended operating pressure of 496 kPa (72 psi) that the CSIR prototype?s sound power was 10 dB(A) less then that of the SECO S215.

Jan 1, 2009

By D. J. Murdock, Wyslouzil, I. M. Flint

The highly competitive nature of the international iron ore market has forced producers to improve the quality of their pellets. The demand for low-acid pellets suitable for direct reduction has resulted in an increase in the number of plants utilizing reverse froth flotation for silica reduction. Column flotation is being favored for this service because of low capital and operating costs and improved metallurgical performance compared to conventional flotation cells. This paper describes the benefits of column flotation and discusses some important aspects of circuit design.

Jan 1, 1995

By W. J. Kennedy, J. D. Gardner

A systematic method is presented for analyzing and improving energy costs in surface mines. Each mine is divided into drilling and blasting, overburden haulage, ore haulage, crushing and grinding, and lighting system. Specific methods of improving the energy costs of each system are discussed. Contributions of simulation and queueing to energy cost reduction are also discussed.

Jan 1, 1985

By Günther Staudinger

Aperam is a global player in producing of stainless, electrical and special steel qualities. The steelmaking plant in Timoteo Brasil is equipped with one AODconverter for stainless steel and one MRPL-converter for special steel production. The MRP-L converter is almost in operation for 20 years. In order to improve production Aperam decided to install a new converter with increased reaction volume equipped with DANIELI state of art technology. This paper describes the major changes and improvements of the new converter installation.

Aug 16, 2017

By N. S. Raghavendran

Based on the weld pool length and width calculations due to an empirical model (1) for submerged arc weld metal, an elegant quantitative definition of tandem submerged arc welding is established. On the basis of this theoretical consideration optimum welding parameters for joining 25 mm thick low carbon steel plate in two passes by tandem wire submerged arc welding have been experimentally found out. An assessment of the metallurgical quality of weld metal and the dependence of mechanical propenies on pool overlap has been made. Also the solution of Rosenthal (2) etc. for a moving point source of welding, which was used as a guide line in formulating the empirical model for the calculations of weld pool dimensions, is compared with the solution of empirical model for submerged arc weld pool dimensions.

Jan 1, 1990

By James L. Parks

This paper describes improvements in SAG and AG mill liner designs and their cumulative effect on wear life and mill availability. Routine procedures used by many SAG and AG mill operators to improve liner life are reviewed. Guidelines are provided for estimating the time required to replace worn liners along with practical methods to reduce downtime for liner replacement. Finally, the effects of mill operating conditions on liner wear life and breakage are considered.

Jan 1, 1998

By D. Royston

Curved pulp lifters can provide improved discharge performance from SAG mills, especially for the coarser fraction of rocks in the discharge. They also can provide improved wear life of the pulp lifter, especially the base of the pulp lifter and diversion cone, over comparable straight radial pulp lifters. Current experience with curved pulp lifters and associated grates is covered including design issues and discharge performance for both the slurry and rock components of the discharge.

Jan 1, 2003

By J. L. Arola

Since start-up of fluxed pellet production in August: 1987, the Minorca Mine has made a number of process changes to improve pellet quality and productivity. Quality improvements include: 1. Installation of a contraction t:ester. 2. Installation of on-line calcium and silica analyzers. 3. Process autocation changes. Productivity improvements include: 1. A second fluxstone storage bin and feeder. 2. A new vacuum pump and disc filter. 3. A filter aid addition system. 4. Enclosing the filter cake reclaim feeder. 5. A new grate bar cleaner.

Jan 1, 1989

By M Freeman

Significant improvements in the metallurgical performance at Pasminco Rosebery Mine have occurred over the last two years. Lead and silver recoveries have increased by more than ten per cent, lead concentrate grades are four per cent higher, zinc recoveries are up 1.5 per cent, and zinc concentrate grades have increased by two per cent. These impressive results have not occurred through the application of some new wonder reagent, but through the application of some fundamental metallurgical principals. The basic premise applied during this study was that to make an effective separation you must first achieve liberation. Therefore, the laboratory and plant studies examined the liberation characteristics within the lead circuit, and the impact of regrinding. The work demonstrated clearly that galena/sphalerite liberation was poor, and significantly impaired plant performance. Further, it was suggested that the application of lead regrinding of the lead scavenger concentrate and the lead first cleaner tailing would not only benefit lead metallurgy, but also improve sphalerite flotation. A similar approach was then applied to the zinc circuit. From these studies, solutions applying simple circuit changes utilising existing equipment were proposed and implemented. Further to the improvements in galena/sphalerite liberation, significant improvements in concentrate quality were achieved by reducing variation within the process. The implementation of changes in work practices negotiated in the Enterprise Agreement, employee contributions and specialist training also made a significant contribution to the unprecedented improvement in the lead and zinc flotation circuit performance. The results of these plant changes are discussed, along with the suggested scope for further improvement.

Jan 1, 2000

By M Costa, L Polizzi

Process optimisation and continuous improvement are usually acknowledged when making a process more effective, efficient and transparent. During the last few decades, thousands of companies around the world have used total quality concepts in order to establish a continuous improvement process in their companies. Typically these companies apply some kind of Kaizen-type tools and expect results in the short term; however, the great majority of companies are poorly implementing these continuous improvement programs.Usually the most common reasons for failure of the program are lack of commitment from leaders, lack of discipline and engagement from the team to follow process and lack of clear targets for the program. When the results do not come at the expected timeline, it is common to simply drop the current process and apply a different approach from another company or consulting firm.This paper will explore some successful cases of companies that have invested time and effort to establish a reliable and sustainable process of continuous improvement. The focus will be case studies of mines and smelters around the world that use the plan–do–check–act (PDCA) cycle to increase productivity with the best services and lowest costs. The main tools and processes used by these companies will be discussed, as well as results achieved.CITATION:Costa, M and Polizzi, L, 2014. Introducing and sustaining a continuous improvement program in mines and smelters, in Proceedings 12th AusIMM Mill Operators’ Conference 2014 , pp 55–62 (The Australasian Institute of Mining and Metallurgy: Melbourne).

Sep 1, 2014

By R. Robertson

Dense medium cyclones are the preferred means for cleaning 112 in. x 14 Mesh to 28 Mesh (12.7 mm x 1.0 mm to 0.6 mm) raw coal and are becoming a common choice for cleaning raw coal from a nominal top size of 2-1/2 in. to 3 in. (63.5 mm to 76.2 mm) down to 14 Mesh to 28 Mesh (1.0 mm to 0.6 mm). During the last ten years, dense medium cyclone circuitry design has undergone changes which have combined to improve process efficiency. This paper describes these improvements and compares present day design with the design used prior to the mid 1980's. Improvements in the following areas are described: Raw coal desliming, cyclone configuration, drain and rinse applications, dilute medium circuitry, and instrumentation and control.

Jan 1, 1997

By Carle R. Hayward

ATHOUGH there are signs of improvement in the lead industry, conditions are still far from what we have been accustomed to call normal. There has been little to stim¬ulate research and those responsible for the finances of the companies have been inclined to discourage expenditures except where need was urgent or the prospect for immediate returns bright. In spite of this fact, improvements have been developed here and there which will be available as business conditions become adjusted. No publicity is allowed at present. The rising price of silver has had a tendency to increase the production of lead from argentiferous ores but the greatest interest continues to be in the secondary field. Practically all lead plants situated near large centers of population are treating scrap materials, particularly battery plates, the quantity of which is increasing with the improvement in automobile sales.

Jan 1, 1936

By Patrice Chartrand, Halvor Dalaker, Philippe Ouzilleau

A size-dependant thermodynamical model for the carbon-hydrogen previously developed by Ouzilleau et al. [1] has been expanded here to include chemisorption of methyl groups. Gibbsenergy minimalisation calculations using FACTSAGE software on this model indicates that hydrogen bonding through methyl groups is energetically favoured as an intermediate between bonding as monoatomic hydrogen to edge hexagons (which is more favourable) and as monoatomic hydrogen to corner hexagons (which is less favourable). The model has also been applied to methane decomposition and oxide reduction using natural gas. A C-H solid solution as a thermodynamic description of the solid carbon phase influences calculations of carbon activity in metastable methane, and gives different results than when using graphite.

Jan 1, 2015

By Julian Wills

The Candrill was developed with Soredem as a one-operator rockdrill for Canadian narrow vein mining. It provides the benefits of increased drilling rates, lower noise and vibration, mass reduction of 20% and system cost saving. The Candrill is to be commercialised at the end of 2001 together with a stoper drill through Parts Headquarters, Novatek's Canadian agent. The Candrill or pneumatic drills may be further exploited using a simple mechanised drilling system to further reduce operator labour, improve drilling speeds by up to 50% and to enhance drilling accuracy. Novatek's drilling system for simple mechanisation in gold and platinum mines is integrated with roof supports, can operate in stope widths as low as 800 mm and has resulted in labour savings of 50%, improved advances per blast of 20 to 50% and improved operator safety and ergonomics.

Oct 1, 2001