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By C. A. F. Sweet

The inter-relationship between these parties and the effect on the outcome of the project is often grossly underestimated. There are numerous success stories where the parties have worked as complementary teams aiming at the best outcome for the client company and achieving significant success. While there are a good number of occurrences where either the roles of the parties were unclear or perceived to be different from what others in the team believed or required them to be and the results were less than desired. This usually resulted in ongoing conflict, incorrect focus, working to different agendas and the result being a less than optimum result to Client Company. Mining, by its very nature of exploring where you cannot see, be it a shaft being sunk, tunnel being developed or other excavation that needs to be made, requires a very special working relationship between the parties. To understand this, and it applies equally well to mine and plant construction and other multiple function projects, one needs to start by describing the relationship of the parties. Often people believe that because they manage ongoing complex operations and large numbers of people that they can manage projects and as such the participants will ?fall into line.? At the outset it needs to be stressed that ?Project Management? is a specific type of management and needs to be understood as such. There are enough Colleges and Universities that teach project management, not only as a subject but also as a Master Degree. As you start up your project the relationship you establish between the client, project team (C.P.T) and the Engineering, Procurement, Construction and Management team (EPCM) will largely determine how successful your project will be. It is essential that from the outset a spirit of co-operation, support and respect be nurtured, and that it be actively carried through the project life cycle. There are several methods to facilitate this including team building exercises right at the start. This time and money will be well spent and recouped many times over during the project life cycle.

Jan 1, 2005

Mr D. Twigg graduated in Metallurgy at the Sheffield Polytechnic, and later obtained a Master of Science degree at the University of Bradford. Mr I.D. Matthews matriculated at Roosevelt High School and joined the No. 1 Parachute Battalion in 1968. He worked in Zimbabwe for 31 years in geological prospecting, civil engineering, and open-pit mining.

Jan 1, 1985

By S. Ata, Y. Pan, S. Gautam, G. Bournival

Bubbles play a vital role in flotation, and their properties directly affect the flotation performance. Xanthates are one of the major collectors used in sulphide mineral flotation. It is often believed that their main function is to render the desired mineral surface hydrophobic, which is essential for the mineral particles to attach to air bubbles. This paper takes a systematic approach to assess the influence of potassium amyl xanthate (PAX) at the air–liquid phase and its interaction with the frother in the concentration of range 10–5×104 ppm. Bubble size was measured in a laboratory flotation cell using a photographic technique and the stability of bubbles was quantified in terms of coalescence time -, the time required for a bubble pair produced at adjacent capillaries to merge into a single bubble. Bubble size reduction of up to 26% was observed with increasing PAX concentration in the cell. The bubble coalescence experiments using PAX only showed that the bubbles coalesced quickly at lower concentrations (10–50 ppm), but they stayed extremely stable at higher concentrations (1×102–1×104 ppm). Further experiments were carried out where the concentration of PAX was fixed at 1 ppm and 4- Methyl-2-pentanol (MIBC) concentration was varied. The synergetic action of PAX and MIBC significantly improved the stability of bubbles in the mixed system, and is even compatible with a stronger frother. The results strongly suggest that the role of PAX at the air–liquid phase should be considered in the practice of sulphide flotation. Keywords: Bubble size, bubble coalescence, PAX, bubble stability

Jan 1, 2020

By Marek Dworzanowski

Dense medium separation (DMS) is critical to the operation of coal and diamond beneficiation plants. It is also utilised in iron ore, manganese, chromite and andalusite beneficiation as well as pre-concentration for platinum-bearing UG2 ore. Gravity concentration plays an important role in the processing of diamonds, coal, gold, platinum, titanium minerals, zircon, chromite, iron ore and manganese. The DMS and Gravity Concentration operations and technology in South Africa conference will focus on the operation of DMS and Gravity Concentration circuits in the South African Mining Industry. The current status of the technologies and equipment employed will be presented as well as future developments. The conference was set up to showcase South African DMS and Gravity Concentration operations and provide a forum where operators, technology and equipment suppliers can engage in knowledge sharing. The papers cover a wide spectrum of topics, including descriptions of operations, optimisation projects, new capital projects, equipment applications, process monitoring and process selection. Most commodities and unit processes associated with DMS and Gravity Concentration are covered. The conference venue was selected to be the CSIR Convention Centre in Pretoria. The CSIR has contributed to DMS research in South Africa and it is located not far from many coal, diamond, gold, platinum and chrome mines that extensively utilise DMS and Gravity Concentration in their beneficiation plants. I believe that the papers and presentations submitted for this conference will provide a valuable future reference for DMS and Gravity Concentration, thus making the work of all the contributors to this conference highly rewarding and worthwhile.

Jan 1, 2006

By E H. O Meyer, K van Dyk

Fine powders normally exhibit, to a more or lesser extent, some ability to participate in dust explosions. Zinc dust as used in the extractive metallurgy of zinc, is not known to be a reactive powder in the industry. No evidence could be found in the literature where zinc dust was involved in an explosion or explosive type event. On 3 May 2002 an explosive type incident occurred at Zincor in Springs, South Africa, which led to a fatal accident. Given the history of relative benign behaviour of zinc powders under conditions conducive to dust explosions, it was decided to share the information of this incident with industry in an effort to prevent similar incidents. Therefore, the purpose of this paper is to describe the incident that occurred at Zincor, discuss the major findings, report on corrective actions, as well as publish the results of subsequent tests that were performed to determine the conditions under which zinc powder exhibits explosive characteristics.

Jan 1, 2005

By V. Labiouse, R. Gärber

The paper aims at clarifying the up-to-now misappreciated role taken by pore water on the design of deep tunnels in saturated porous media. Numerical simulations with a non-dimensional FEM-model emphasise the influence of pore water characteristics (in situ pressure and compressibility) and boundary conditions (lining permeability) on the short and long term underground-structure equilibrium states. These results cannot be achieved by means of monophasic total stress analyses. Dieser Beitrag untersucht den Einfluss des Porenwassers auf die Dimensionierung von tiefen Tunnelbauwerken in wassergesättigtem Untergrund. Numerische Simulationen mittels eines dimensionslosen FEM-Modells betonen den Einfluss der Porenwassereigenschaften (in-situ Druck und Kompressibilität) und der hydraulischen Randbedingungen (Tunnelausbaudurchlässigkeit) auf Kurz- und Langzeitverhalten des Untergrund-Ausbau Gleichgewichts. Diese Ergebnisse können nicht ermittelt werden anhand von Einphasen- und Totalspannungsmodellen. L’article s’intéresse au rôle méconnu de l’eau interstitielle dans le dimensionnement de tunnels profonds creusés dans des milieux poreux saturés. Des calculs adimensionnels par éléments finis soulignent l’influence des caractéristiques de l’eau interstitielle (pression in situ et compressibilité) ainsi que des conditions aux frontières (perméabilité du revêtement) sur les équilibres court et long terme de l’ouvrage. Ces résultats ne peuvent pas être obtenus par des calculs en contraintes totales.

Jan 1, 2003

The Steering Committee for Minerals and Mining Policy convened two workshops during March 1996 to address the following topics: Business Environment- National and Provincial Powers, Administration and Regulation, Mineral Marketing, Beneficiation, Research and Development, Environmental Issues, Mining Impact on Surface Usage, Southern Africa Regional Issues. Human Resources: Elementary Residual Racism, Housing, Downscaling, Migrant Labour and Human Resource Development. Mineral Tenure: Mineral Rights, System of Access to Mineral Rights, Access to Exploration information, optimal Exploration, Trust Lands. Small-scale Mining. Development of Small-scale Mining, Artisanal Mining.

Jan 1, 1996

By Ron Tluczek

[Power Point Presentation]

Jan 1, 2006

By Raphael Banda

1 Initiating Systems ? a definition An initiation system is a combination of explosive devices and component accessories specifically designed to convey a signal and initiate an explosive charge from a safe distance. In the use of explosives, the initiating system performs the functions of transmission and control of the firing signal to each explosive charge. As functional groups, initiating systems may be considered as: Starters Those which provide the initial signal to start the blasting process. Surface systems Products which provide transmission of the starter signal and delay timing (if any) across the surface of the blast outside the blast hole. In-hole systems Products which provide the signal transmission, delay timing (if any) and the initial explosives energy in the blast hole.1 2 Different types of Initiating Systems The initiation systems commonly used in Sub Saharan Africa are: ? Detonating cord and detonating relay systems ? Capped fuse and igniter cord systems ? Shock tube non electric systems ? Electric systems ? Electronic detonators 3 Overview of Electronic Delay Detonator Technology Conventional detonators use pyrotechnic delay elements and the variation of the actual delay periods is at best approximately 1% the nominal delay. The lack of guaranteed precision common to all pyrotechnic systems enhances the likelihood of negative environmental blasting effects.3 For example, take a 500 ms in hole delay. In conventional detonators this means that 95 % of shots fire within 10 ms of the mean. i.e. a window of 20 ms. Taking a fixed interval between shots of 25 ms, with a range of ± 3 ms, a very ragged firing pattern could be expected which in practice would result in non uniform fragmentation.

Jan 1, 2005

By A. R. Leach

Anomalous mining conditions can be described where the level of hazard is increased relative to normal conditions within a mining area. Normal conditions would be those defined as a Ground Control District in a mine’s code of practice, and for which mine standard support layouts are generally developed. It has been found that up to 80% of fall of ground accidents occur where anomalous mining conditions exists, typically in the vicinity of geological weaknesses. These areas require specific attention to ensure they are readily anticipated and identified and that appropriate strategies are used to reduce the hazards associated with them. As part of SIMRAC project GAP 607 checklists to aid identification and best practice mining methods were identified for a range of geotechnically anomalous conditions.

Jan 1, 2003

DD3-tunnels (PD BH's) ? Rotary coreholes 111no. (124) ? Percussion holes Ono. (37) ? Sampling (rock and soil) ? Soil and rock permeability ? testing ? BH Televiewer Surveys [ ]

Jan 1, 2007

By T. S. Golosinski

The paper reviews current status of online education related to mining, and reports on the online Master of Engineering programme in Mining Engineering that is offered at the University of Missouri-Rolla since 2001. Keywords: Online education, learning, teaching, mining engineering, mining education online

Jan 1, 2003

By C Katongo

Ground condition at No1. Shaft varies across the mine. The different ground conditions arise as a result of the differences in the rock strength and structure, seismicity and induced stresses in abutments areas. Apart from being a major cause of Fall of Ground incidents/accidents, adverse ground conditions where encountered has affected the rate of development advance as well as production. This implies that for support to be cost effective Geotechnical section has to ensure that support is designed to prevailing ground demand to ensure the safety of personnel and minimize loss of production. We have also seen changes in mining methods as a result of change in ground conditions. To avoid incurring unnecessary costs through remedial works resulting from ground deterioration and collapses of development openings due to inadequate support, the principle in engineering design is ?Do it right the First Time?, and this can only be achieved through good understanding of Geotechnical environment. The paper discusses the different ground conditions encountered in various development ends at No.1 Shaft. It also discusses the principles of ground support, failure mechanisms, types of ground support systems employed, and the different techniques used to select support systems, and quality control techniques in underground support installation.

Jan 1, 2005

By D. Noort, M. Dawborn, D. O. del Castillo

This paper was originally presented at the North American/9th US Ventilation Symposium, June 2002, Kingston, Ontario, Canada. Reprinted with permission of the publishers, A.A. Balkema Publishers, Rotterdam, Netherlands. This paper is a study of the ventilation, cooling and refrigeration system design of the Mindola copper mine in Zambia. The challenges that were addressed varied from the restrictions imposed by an ageing infrastructure to the requirement for increasing the annual production rate, coupled to the introduction of a higher level of mechanization while maintaining acceptable conditions and limiting total ownership costs. A description of how the ventilation, refrigeration and cooling systems were modelled in order to obtain the projected heat loads associated with two different mining methods over the life of the project. The methodology included a number of iterations to optimise the design and include aspects such as the expected inrush of hot fissure water, the operation of diesel machinery at depths in excess of 1500m below surface, developing a cost-efficient cooling strategy and selection of the refrigeration machinery to meet the requirements imposed by the cooling strategy. This paper demonstrates the successful implementation of an integrated design approach.

Jan 1, 2005

O.F.S. Branch, Welkom Minutes of a Committee Meeting held in the V.LP. Lounge of the Welkom Club on Tuesday, 26th June, 1973, at 5.00 p.m. Present Mr C. J. Isaac (in the Chair), Mr D. A. Smith, Mr G. Young,

Jan 1, 1974

By P. Pięta, A. Surowiak, T. Niedoba

In a flotation process of copper ore three factors were measured: copper grade in concentrate (β), copper grade in tailings (J) and recovery of copper in concentrate (e). The experiment was conducted by means of the Jameson cell. The factors influencing the quality of the process were particle size (d), time of separation (t), type of the collector (k) and dosage of the collector (s). The considered vector function was then [β(d, t, k, s), J(d, t, k, s), e(d, t, k, s)]. Optimisation achieved was based on determining the values of the adjustable factors (d, t, k, s). The goal was to obtain the highest possible values of functions β and e (maximum) and the lowest possible values of function J (minimum). To this purpose the taxonomic methods were applied. Keywords: Flotation, copper ore, lithology, flotation agents, particle size distribution, taxonomic methods

Jan 1, 2020

By P. Schutte

It is evident from most admired companies, globally, that they drive key priorities such as teamwork, customer focus, fair treatment of employees, initiative and innovation into their organisations. It is clearly proofed in all the research that the role of the human factor, and therefore human behaviour, is pivotal to companies striving to accomplish goals such as competitiveness, customer delight, high quality, growing productivity as well as a safety-committed work force. The challenge of leadership is to change the worker’s poor perception of safety to an excited, empowered, valued employee who is continuously committed to the achievement of high levels of health, safety and conformance – the challenge therefore is to transform from within. Any work force needs a set of behavioural rules which work for it – including safety rules and critical safety behaviours, which are accepted through involvement leadership, encouragement and support.

Jan 1, 2003

By A. K. Biswas

Reviewer: R. H. Eric This edition is organized in twenty-three chapters, and contains exactly 500 pages including three appendices and an index. The first and second editions were published in 1976 and 1980 respectively, and both contained nineteen chapters. The second edition brought the operating data and process descriptions up to date. The third edition covers comprehensively the changes that have taken place in the primary copper industry over the past two decades. For example, reverberatory furnaces now make up only a third of the major primary smelting furnaces, compared with about three-quarters in the 1970s. Control of air and water pollution and recycling are given much more emphasis, along with novel and emerging technologies.

Jan 1, 1995

By Pierre Marcotte

Jackleg rock drills expose their operators to high hand-arm vibration levels. To address this problem, an antivibration handle has been developed. The antivibration properties of the handle were achieved through a suspension based on a hinge design, achieved with a torsion spring and o-rings. To provide some bench marking for this new handle and to follow the evolution of its performance over time, a test bench was developed to characterize the vibration emission values of jackleg drills under controlled operating conditions. Testing of four antivibration handles on the test bench have shown reductions of the overall weighted acceleration level in the order of 54 % to 60 %, with most of the attenuation occurring in the zh-axis at the rock drill percussion frequency.

Jan 1, 2008

The January General Meeting was held at The Moth Hall, Witbank, on Thursday, 30th January, 1969. Mr C. G. Sowry (Chairman of the Witbank/Middelburg Branch) was in the chair. There were also present: Fourteen Members: Messrs A. Bain, A. W. L. Brereton, J. Meintjes, G. Langton, A. C. Hofmyer, J. H. Moore, T. S. Wilmot, B. F. van der Merwe, H. A. Williams, O. T. Wright, J. E. van Aswegen, P. J. Beukes, I. Botha. Six Associate Members: Messrs B. T. Hosking, R. E. Powell, J. B. Cornish, R. Ladner, W. Weber, P. J. Muller. Two Affiliates: Messrs P. B. Cass, W. K. C. Bremer. Nine Visitors. Apologies were received from Messrs G. R. Canny, E. J. Jackson. MINUTES OF THE PREVIOUS GENERAL MEETING It was proposed and accepted that these be taken as read. Proposer, J. Meintjies; seconded, A. W. L. Brereton. 75TH ANNIVERSARY CELEBRATIONS OF THE S.A.I.M.M. The Chairman reminded members of the functions arranged to mark this occasion. It was also mentioned that members desirous of forming parties to travel to Johannesburg should either make arrangements amongst themselves or inform the Secretary who would assist in arrangements. PAPER FOR PRESENTATION The Chairman then called upon Mr S. Selmer-Olsen to present his paper, 'Lectures on electro-smelting of ferro-alloys'. After Mr S. Selmer-Olsen had presented his paper, he answered questions arising from contributions from the floor. The Chairman then thanked Mr S. Selmer-Olsen for presenting his paper. CONTRIBUTIONS TO PREVIOUS PAPERS Contributions to the paper 'Photo-electric readings. Their significance for dust control on collieries,' presented by Messrs G. H. J. Kitson (Member) and Y. J. F. Haven (Visitor), were read by Messrs A. Bain and A. W. L. Brereton.