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By William K. Burriss

Computer technology was applied to solve three problems in the selling of certain industrial minerals to the glass and foundry industries. The computer solutions provide for better service to customers and have helped increase sales. II. Summary Electronic data processing techniques were applied: 1. To automatically and continuously "trace" rail car shipments of bentonite. 2. To aid our sales people in recommending to glass plant purchasing agents which of several possible feldspathic materials is the best value at any of about 100 glass plants and to give guidance on the amount of value difference. 3. To help in locating plant sites for three blending or pre-mixing stations to serve the foundry industry at minimum cost and with maximum tonnage and maximum profitability.

Jan 1, 1968

By Paul M. Tyler, Carle R. Hayward

DOES it pay to do really good work? Quite likely the practical millman will answer that it does not. The preparation of ores for market is primarily a business enterprise, and by and large the individual operator does not bother his head about squandering our national resources or making easier the job of the smelterman. Having accepted such ore as he may get fro111 the mine, his job is to make the best possible showing with his mill fro111 the standpoint of financial return. His success is measured in dollars and cents, and he has no rightful reason to expect more than scant acknowledgment of any other achievements from the stock- holders of his company who in the last analysis are his employers.

Jan 1, 1936

By Jim Hazzard

A numerical investigation is presented to examine fluid flow in fractured rock slopes. In mining geomechanics, different numerical modelling approaches are used to estimate fluid pressures in open pit mines. The most common technique is the Equivalent Porous Medium (EPM) approach in which the fractured rock is assumed to behave as a porous continuum. Depending on the geometry and properties of the problem, this may not always be the best approach. The paper presents a parametric study to examine the effect of fracture spacing, fracture and matrix diffusivity and excavation rate on the fluid behaviour in rock slopes. Based on the model results, guidelines are provided as to when EPM models can be used and when different modelling approaches (e.g., discrete fracture flow) may be necessary.

Jun 1, 2012

By D. G. Lee

Diesel particulate matter (DPM) often contains small amounts of metal as a minor component but this metal may contribute to adverse health effects. Knowledge of the mechanism for particle formation as well as the size preference of the trace metals is critical to understanding the potential for health concerns. To achieve this, the size and the composition of each particle should be optimally measured at the same time. Single particle mass spectrometer (SPMS) would be the best tool for this objective. In this paper, we therefore will introduce new findings about the mechanism and distribution of the trace metals in DPM, derived from a study where an SPMS was used to analyze freshly emitted DPM. KEY WORDS : Single particle mass spectroscopy, Diesel particulate matter, Characterization, Metal contents

Jan 1, 2006

The contribution of minerals to the growth and development of the United States is best demonstrated by the uses which have evolved during the past two centures. During pre-Revolutionary days the colonies were essentially agricultural in character, producing cotton, tobacco, rice, indigo, grains and flour, fish, livestock, dairy products, and timber. Shipbuilding was the major manufacturing industry. In 1763, the total value of exports for Virginia, Maryland, New York, Pennsylvania, and Massachusetts was £2,722,000, of which £55,000, or 2 percent, was for "copper ore, and iron in pigs" (3)1 and £49,000 was for 21,000 barrels or hogsheads of "pot-ash." The value of 75 ships built for sale in 1763 by the colonies was £61,500.

Jan 1, 1976

By Gordon T. Austin

The combined value of production of natural abrasives, which includes tripoli, special silica stone, garnet, staurolite, and emery, increased about 9% in 1988. In the case of emery, the increase was due to an increase in unit value of the material produced. The increase in the value of garnet and staurolite production was simply the result of an increase in the quantity of materials produced. However, special silica stone experienced both an increase in unit value and quantity produced. The nonmetallic manufactured abrasives industry, which includes only silicon carbide and fused aluminum oxide in the reported statistics, enjoyed the best production year since 1981 in terms of total quantity produced. Production increased 22% in quantity and 16% in value com-pared with those of 1987.

Jan 1, 1990

By G. S. Bartlett

The theme of this Colloquium, survival strategies, not only conveys a sense of urgency but also takes cognizance of the fact that, as in the political arena, tough decisions have to be made and acted upon in the years to come. It is therefore appropriate that the SAIMM, as spokesman for the metallurgical industry, should be dealing with these issues at this time, and I wish to commend the organizers of this Colloquium for focusing on a mater as important as the future of this great industry. In view of this, I regard it as an honour and privilege to officiate on this occasion, where the best of South Africa's brain power in the metallurgical field will be harnessed with a view to moulding strategies for survival.

Jan 1, 1993

In accordance with the usual custom, manuscripts to be presented at the next meeting of the Institute must be in the hands of the, Secretary before July 1, 1917. Manuscripts to be properly distributed in advance of the meeting must be in the hands of the Secretary before June 1, 1917. At the last meeting of the Institute 45 papers were presented, and 42 of them were actively discussed. This experience makes us believe that advance distribution is the best possible means of getting a good discussion of papers and of securing for them the interest of the members of the profession. It will be impossible, however, to give the papers proper distribution if they bare not received before June 1, 1917.

Jan 4, 1917

By P. C. Seligmann

Primary fracture from an array of shotholes by c. M. LOWNDS. B.Sc. Hons. (Rhodes). Ph.D. (Cape) (Visitor) and P. C. SELIGMANN. B.Sc. (Witwatersrand) (Visitor) The effects of stress on the directions of cracks that are propagating in a brittle medium are described. It is shown that the superimposition of stress fields from the holes of an array always adversely affects fragmentation. Consequently, the best fragmentation will result when holes are fired far enough apart in space or time for each to develop its whole crack pattern without disturbance from the others. This concept leads to a philosophy for the design of more effective blasting patterns, which has been verified on model scale and which explains many published, empirical results.

Jan 1, 1976

By M. Mrost

Slimes disposal at South African gold mines by M. MROST*. M.Sc. (Rand) (Fellow) The soil mechanics, civil engineering, and environmental considerations applicable to the construction of slimes dams on the Witwatersrand gold mines are discussed. It is concluded that, though the procedures used in the construction of dam embankments do not accord with the best possible practice, they are entirely adequate in current local circumstances, provided that proper precautions are taken to ensure that the wall foundations are sufficiently permeable and strong, and that the dams are protected against erosion. If current trends towards larger mining and metallurgical complexes continue, it may become necessary to build larger, higher dams, and to adopt slimes embankmentbuilding practices that are inherently more reliable.

Jan 2, 1974

By G Hobart

Laboratory flotation tests were conducted to investigate the role of pH, zinc sulfate and potassium metabisulfite in the flotation of galena and marmatite in the Broken Hill orebody. Marmatite was depressed under alkaline conditions alone, however the addition of the two depressants, either individually or combined, resulted in the greatest selectivity. The use of zinc sulfate under alkaline conditions resulted in good selectivity whilst maintaining a high lead recovery. The addition of potassium metabisulfite under alkaline conditions reduced zinc recovery, but high additions reduced lead recovery. The addition of both depressants at alkaline pH produced the best result, with a lead concentrate of 72.6 per cent at 98 per cent recovery with less than four per cent zinc recovery.

Jan 1, 2005

By A Hollonds, R Young

High commodity prices have produced a boom in project expansions and growth projects. Unfortunately, some of the early results have been poor, with some projects suffering considerable cost growth, project delays and start-up problems. The cost growth experienced in some projects is well beyond just escalation, but suggests weaknesses in the development of feasibility studies. Independent project analysis (IPA) has developed a large database containing information on project outcomes in the minerals and metals sector, and has identified, through its front-end loading (FEL) index and team development index (TDI), some key leading indicators of project success and project problems. This paper highlights key areas of weakness in feasibility studies that have driven poor project results, and the best practices that have driven improved project results.

Jan 1, 2009

By Martin F. Milligan

THIS short discussion of the effects of deoxidation on the mechanical properties of cast steels is intended to serve as general introduction to the subject of this afternoon's session. The subject is covered in detail in Mr. Carter's excellent paper. My material has been collected from the works of various investigators, several of whom are present today. For a definition of deoxidation, as applied to steel-furnace melting practice, we can best go to Briggs' book, "The Metallurgy of Steel Castings." Briggs says that deoxidation "includes all the phenomena in the final preparation of steel that would permit it to solidify free from gas cavities and from dissolved oxygen of all kinds." Various practices are used by welters to produce these end results.

Jan 1, 1947

By Robert W. Hunt

No matter how perfectly sectioned or skilfully manufactured the rails used may have been, or with what care the road-bed may he maintained, legitimate results from these important factors cannot be secured unless proper attention is bestowed upon the joint-fastenings. In this country, splice-bars of various patterns furnish the practically universal joint. Other forms have been used, and are now being experimentally tested, but the typical American rail-joint consists of angle-plates or splice-bars. At the same time, it is true that scarcely a railroad engineer is satisfied with his joint. He may consider it the best of which he has knowledge, but at the same time he is well aware of many of its weak points.

Jan 1, 1890

Competition in the mining industry is the main driving force for both equipment manufacturers and end users to develop and apply the most cost efficient solution to a mining problem. Therefore the challenge to find new solutions is usually met by several suppliers under various factors of influence affecting specifications. Time and timing are particularly important, but all new developments ultimately have to successfully perform on site.Consideration of all aspects of planning, manufacturing, user liaison and ultimate satisfactory commissioning hinges on the necessities of assessing of all the expectations in the mining application and the requirements of the concept and layout team. To apply the maximum available technical competence with solid thorough workmanship is the best possible foundation for success of underground machinery development.

Jan 1, 1991

Mine scheduling is a process which represents what happens in a mine over time. An optimised plan involves selecting the best workable plan which meets a stated objective. This paper discusses some of the theory and philosophy behind mine scheduling and explains how scheduling is a step in the total iterative mine planning process. Several schedules may be necessary before arriving at a mine plan which can be considered optimal. A description of broadbrush and detailed scheduling is given and the features of computer assisted scheduling are also described. The use of mathematical modelling techniques in conjunction with scheduling to optimise the mine plan is explained. The need to incorporate these techniques to optimise the whole mining system rather than only a part, is emphasised.

Jan 1, 1991

By S. K. Bhoumik, D. K. Sengupta, B. P. Singh

This paper deals with experimental work to improve the settling and filtration characteristics of an industrial sludge from an iron-ore mine using synthetic polymeric flocculants. The experimental work consisted of the characterization and evaluation of suitable flocculants to enhance settling and filtration rates. The optimum dosage of the flocculants were determined. The experimental results revealed that the settling rate can be increased many times, compared to untreated sludge, by using a suitable combination of flocculants. Compared to cationic and nonionic flocculants, anionic flocculants were found to be more efficient in sludge flocculation. The synergistic effect of two anionic flocculants produced the best settling conditions. Filtration test results also reveal that suitable flocculants can improve the dewatering characteristics of the slurry.

Jan 1, 1997

POSITIONS VACANT (Under this heading will be published notes sent to the Secretary of the Institute by members or other persons.) Advertising Manager for Machinery Manufacturing Company. Must have technical training. No. 94. ENGINEERS AVAILABLE (Under this heading will be published notes sent to the Secretary of the Institute by members or other persons introduced by members.) Member, technical graduate in Mining, Chemistry and Metallurgy, Post-graduate, Royal School of Mines, Freiberg, Saxony, Germany and Columbia School of Mines. Aged 37, 14 years' experience in teaching mining metallurgy, chemistry and assaying. Available now. Willing to go anywhere. No. 278. Member, aged 33, mining engineer, 88 years' experience, desires position as mine safety and efficiency engineer with coal company. Best of references on request. No. 290.

Jan 5, 1916

The issues which are the subject of this paper cover an extremely broad field. In themselves the components of the topic could be the theme, in considerably greater detail, of a two day seminar. Indeed a full course in an academic year would probably not do justice to the topic. I have therefore experienced considerable difficulty in condensing such a broad subject range down to a 30 minutes address and in doing so have tried to, hopefully, provide a little bit of everything for the wide range of professional interests and different levels of commercial, professional and legal expertise represented at this conference. Perhaps my address could best be described as a "bird's eye" view rather than a "worm's eye" view of the subject.

Jan 1, 1990

The determinants of human behaviour are numerous and complex. Many scientific disci- plines focus on various processes which play some part in shaping the actions of individ- uals and groups. Behavioural science attempts to synthesise data produced by these investigations in an attempt to formulate principles by which people's thoughts, feelings and actions may be described, diagnosed, predicted and changed. While no comprehensive account of people and their reactions can be attempted in a brief paper a review of six principles does provide a framework within which managers can establish reliable knowledge applicable to all their subordinates and to themselves. This information may be used to arrange organizational environments and management practices which enable people to discover, release and increase their best intellectual, emotional and motivational capacities.

Jan 1, 1982