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By Normand Champigny

The Forces of Change ? The current business environment ? What can we expect for the future on management of physical assets ? The impact of maintenance on production costs ? What is RCM is doing is improving business performance ? The beginnings of RCM The RCM II Process ? RCM II is a structured process that involves employees in determining the best failure management tactics for systems and equipment in their operating context ? The method is an effective approach to risk and cost reduction as well as failure management

May 1, 2002

By T. C. Sun

Two wasted activated sludges (WAS), from an industrial wastewater treatment and a sewage treatment plant respectively, and 7 collectors are used to investigate the feasibility of air flotation thickening of WAS by adding the collectors used in mineral processing. The collectors experimented include straight chain fat acids with different chain length, sodium oleate, alkyl sodium sulphonate, sodium dedecylsulfonate, and dodecylamine. The results show that the thickening efficiency varied depending on different collectors. Of the collectors experimented, dodecanoic acid and dodecylamine are best collector for thickening both sludges.

Jan 1, 2014

By W. Riekehof

The paper explains required practice and equipment for capturing airborne fumes and particulates in hot-dip zinc galvanizing plants. An economic and technical comparison of enclosure and tank rim suction options is presented. The paper also compares the performance of various filter media in filtering fumes, to determine the effect of changes in flux as well as changes in filter finishlcoating methods. This includes a recommendation for how to achieve the best result with respect to pressure loss and cleaning behavior of the filter.

Jan 1, 1992

By Ben Bowman

For certain ferroalloy furnaces, such as ferrochrome or ferromanganese, there is still doubt about the mechanisms operating under the electrode tips. In this paper a model is built that does not call upon an arc. The medium is best described as an electrically conducting slurry, a mixture of liquids, solids and gas. There are two sources of propulsion, the Lorentz force within the conducting part and buoyancy generated by CO bubbles, creating two opposed poloidal circulation loops, downward below the electrode axis and upward further out.

Jan 1, 2014

By E. O. RHODES

Germany's' wartime coal-tar industry had two main branches, which can best be considered individually because their raw materials, operations, and distributions were almost completely separated. One branch, old and well-established, was concerned almost entirely with processing coal tar produced by the high-temperature carbonization of caking bituminous coal. Carbonization was effected principally in byproduct- coke ovens and to less extent in vertical, horizontal, and inclined retorts. The high-temperature tar was all processed in tar-distilling plants that handled high-temperature tar almost exclusively.

Sep 1, 1947

By A. Viksne

A series of tests were conducted by the Bureau of Mines to determine the best means of reducing noise generated by the detonating cord that is utilized for trunklines in quarry blasting. Ten different types of detonating cord were tested and evaluated for their acoustic qualities. The results of the investigation showed that noise levels produced by "low-core-load-per-foot" detonating cord "not covered" were lower than those produced by "high-core-load-per-foot" detonating cord covered with 6 inches of unconsolidated material.

Jan 1, 1972

The following situation was submitted as an ethics case study for inclusion in the Journal. To the best of our knowledge, they are based on actual circumstances encountered in the field. Blowing the Whistle Protecting Confidentiality or Doing the Right Thing? This case centers around a construction job and involves a contractor, subcontractor/blaster, and a farmer/homeowner who lives near the job site. It is essentially a study of professional ethics versus morality, our professional code of conduct versus what is right or wrong.

Jan 1, 2007

By L. W. Blau

THE entrance of geophysics and geochemistry into petroleum engineering may be viewed with apprehension by some engineers. They may not remember the time when "practical oil men" opposed the invasion of engineers into the field of petroleum production. By their excellent contributions they established themselves. In the popular mind, engis veers are practical men whereas physicists and chemists are suspected of being theoretical. It will be best to annihilate this misconception right now at the beginning of a closer relationship between petroleum engineers. geophysicists, and geochemists.

Jan 1, 1943

By R R LARGE

In the past decade mineral deposit models have become an important tool for the exploration geoscientist. By combining genetic theories on the formation of particular deposit styles, with geological, geochemical and geophysical criteria relevant to ore location, it has been possible to more effectively focus exploration effort to the regions and local targets which have the best chance of success. However, such models have their limitations, and must be carefully and critically applied and continually updated as new technical and research information becomes available.

Jan 1, 1992

By J. R. Ross

Techniques for recovering scandium from uranium plant iron sludges and from wolframite concentrates are described. The best procedure found comprised (1) dissolution with sulfuric acid, (2) preliminary concentration by solvent extraction with a primary alkyl amine, (3) further enrichment and purification by a combination of ion exchange, solvent extraction, chemical precipitation, and calcination. Recovery of scandium from these raw materials, which contained 0.058 and 0.14 percent scandium, ranged from 83 to 90 percent in products analyzing 99.6 to 99.9 percent scandium oxide.

Jan 1, 1965

The Role of the Drilling Contractor BY FERRIS E. SAINSBURY Ron Haxby, Occidental Minerals What is the best method for drilling a 12-in. diam hole to a depth of 1200 ft and maintaining the deflection within 25ft from vertical? Ferris Sainsbury: In order to drill a 12-111. hole down to 1200 ft, In most places you would have to employ a rotary tricone bit With a down-the-hole hammer, I expect by that depth significant Inflows of water would be experienced Even with foams, we would not be able to get the water out of a hole of that diameter So the down-the-hole tricone method of drilling would be best. To keep it straight, we would probably employ the largest square drill stem compatible with the diameter of the hole. Ron Haxby: Is it common in drilling contracts to put in a vertical hole clause? Ferris Sainsbury: You can put in the vertical hole clause Ron Haxby: Does it cost more? Ferris Sainsbury: Normally, if the hole deviates, the driller can correct it with deflection wedges and will charge it back to you at cost, plus 10% or somewhere along that range Any drill hole has a tendency to go perpendicular to the dip, and there are times when stabilization systems are not successful in preventing the hole from turning into the dip of the formation. The only solution, in this situation, is to go in with an oriented wedge and kick the hole back out.

Jan 1, 1979

By James E. Lonergan

To determine the best materials handling system for surface mined materials, one must develop a mine plan for each candidate system based on the most efficient use of that system. This is essential for a fair, unbiased economic compari¬son of the candidate systems. This paper will present two case studies where an integrated mine planning /systems engineering approach has been utilized at different levels of detail in the analysis of an in-pit crushing/conveying system vs. total truck haulage at 2 open-pit copper mines.

Jan 1, 1985

By J Harris, P Kirsch, D Cliff, M Spinks, S Goater, D Sprott

Fires are a common and recurrent unwanted event in the operation of open pit mines. In most cases, the causes of events such as fires are already æknownÆ but are either overlooked or not fully addressed in planning. Ongoing rapid growth of the global mining industry is creating a scarcity of skilled personnel, and high turnover within operations. This contributes to loss of corporate memory in risk management activities. RISKGATE« is an online risk management system designed to support and assist in the analysis of priority unwanted events in Australian coal mining operations. Funded by the Australian Coal Association Research Program (ACARP), RISKGATE« is a knowledge management program that delivers best-practice controls for unwanted events and assists operations in staying abreast of emergent risks and threats. RISKGATE« content has been primarily developed from an association of industry experts, and enriched with input from additional academic and technological resources. In mining operations, RISKGATE« provides a continuum of knowledge and best practice for risk identification, assessment and management. RISKGATE« will assist companies in improving safety performance, operational efficiency, operating practice and training. Here we present the RISKGATE« prototype as developed in 2011 for Fires, with a case study presented for the initiating event Fires on Mobile Plant.CITATION:Harris, J, Sprott, D, Spinks, M, Cliff, D, Goater, S and Kirsch, P, 2012. RISKGATE« - A case study in application to fires on mobile plant, in Proceedings Eighth Open Pit OperatorsÆ Conference , pp 49-54 (The Australasian Institute of Mining and Metallurgy: Melbourne).

Sep 18, 2012

By F. B. JEWETT

TWENTY FIVE years of doing, finding, and encouraging others to do scientific research in' industry, and of organizing the machinery for the` smooth 'and effective conduct of such research, have left me with a feeling that so far as this branch of human activity is concerned the problems in 'essence are- not, materially 'different from those met elsewhere. Years ago, in a less mature period of life, I may have thought that the effective industrial research man was a being somewhat different from his fellow workers in adjacent 'fields, but I have long since 'changed my views. The rank and' file of the modern industrial research organization are relatively easy to find, though some¬times difficult to get in sufficient numbers. Mistakes in choosing them are not particularly serious to the or¬ganization, however unfortunate they may be for the misplaced individual who persists too long in the wrong environment. The reason for this is obvious from the fact that, taken by and large, the work of the rank and file is at best necessarily a work of detail done under guidance of the more experienced. In this respect the situation of the rank and file in an industrial research organization is not different from that class in any other group activity, whether concerned with industry, the university, or the church. This does not mean, however, that we are not all anxious to have the best possible material obtainable in the rank and file, or that we are indifferent to the utmost of encouragement and stimulation to its individual members.

Jan 1, 1929

By Haley, D. F.

WHEN operations were first started at Climax in 1917 by the Climax Molybdenum Co., they were pioneering in the molybdenum industry for little was known relative to the uses of molybdenum or the metallurgy of molybdenite concentration. Concentration of molybdenite is relatively simple today but in 1916, when the Climax deposit first attracted attention, it presented serious difficulties. Little was known, in fact, even about the assaying of such low-grade molybdenum ores. Mine samples were sent to at least a dozen of the best laboratories in the United States and average values reported varied from 0.4 per cent to 1.0 per cent MOS2. Owing to the wide variations in MoS2 content obtained from reliable chemists, the actual value of the ore was most uncertain. This variation occurred repeat¬edly over a period of six months in 1917. It was finally decided, as a last resort, to cut several tons of sample from the tunnel and have a mill test made, using the recovered MoS2 per ton as the grade of the ore, for a small error in the assaying of the concentrate would not materially affect the results. These mill tests were made by the General Engineering Co. (Callow) at Salt Lake City. The results proved an ore of commercial grade and indicated the flotation process for the best metallurgy. Based upon these tests, the decision was made to build a 200-ton flotation plant. At this time, the art of flotation was

Jan 1, 1946

By Thomas M. Nasiatka

Tests with a high-pressure water jet were conducted in the steeply pitching Roslyn No. 5 bituminous coalbed in the Roslyn No. 9 mine, Roslyn, Wash., to determine the feasibility of extracting coal from pillars and from a solid coal face in development without drilling and blasting. During pillar mining, using a hand-held monitor, the best results were obtained with a 0.150-inch- diameter nozzle, a water pressure of 3,500 psi, and a flow rate of 38.5 gpm.3 The rate of mining and productivity were 0.74 ton per minute and 16.6 tons per man-shift, respectively. During development mining, using a monitor mounted on a roof jack, the best results were obtained with a 0.148-inch-diameter nozzle, a water pressure of 4,500 psi, and a flow rate of 40.0 gpm. In one section of the mine where the coal was relatively hard, the rate .of mining and productivity were 0.10 ton per minute and 5.7 tons per man-shift, respectively in another section of the mine where the coal was relatively soft, the rate of mining and productivity were 0.51 ton per minute and 8.3 tons per man-shift, respectively. The tests showed that hydraulic mining methods were more productive than conventional mining methods in pillar mining. In development the productivity of hydraulic mining depended primarily upon the coal hardness. Compared with conventional methods, hydraulic mining methods were less productive where the coal was relatively hard and equally as productive where the coal was relatively soft.

Jan 1, 1963

By J. Starkey

A comminution circuit in recent history, is one of the most difficult parts of a mineral processing plant to design with confidence. It is usually the most costly part of a plant to build, and it can consume up to half or more of the energy used on a mine site. To suggest that comminution energy usage is sustainable in the long term is not possible at this time. What we have to choose from today, based on more than 50 years of experience, does include the best available technology, and the best way to design it. There is controversy in the industry as to how to properly approach the subject of comminution design, with many of the optional solutions requiring a level of training and expertise beyond the ability of a non-specialist engineer. Semi-autogenous grinding technology in particular, has not been properly appreciated because of many recent mistakes in its application and design, which have blurred the positive perception about what SAG technology is, how it can be used, and how it needs to be designed and built. In order to change this, mine owners and senior managers need to take responsibility for, and learn to understand the fundamental challenges that a comminution circuit poses to the project, to the design process, to the operators who use the equipment, and to the resulting metallurgy. This address is intended to summarize these challenges and offer fundamental engineering solutions, which are clear, specific and in a format which is directly applicable to the mining and mineral engineering community.

Jan 1, 2018

By Carlos Renato Inchoste Meure, José Ernesto Boff

Nowadays, many companies have the idea where to be occupied is to be productive, this work aims to show with practical tests that to get the best performance of the machine with tools of high performance and yield is the best option for a company to become productive and economic at the same time . The company targeted for this work began its activities in the Metallurgical branch more than 75 years, Metisa Metalúrgica Timboense serves the national and international market with several product lines. Due to its large backlog of overdue hours, a job was started in the tooling sector to make the process faster and more economical. In this context, this work has as general objective the restructuring of the critical processes of the tooling sector, aiming at a better functioning of the organization and greater satisfaction of its direct clients. In addition, this work has specific objectives, such as (1) application of high performance tools, (2) analysis and improvement of existing processes, development and application of new processes, (3) (High Speed Machining) (4) production monitoring and technical support for maintenance of new processes. Thus, after the implementation of the process improvements, it was possible to obtain a reduction of 81% in the final cost and 80.5% in the process time. In addition, with some of the new processes deployed, there was a reduction in the use of personal resources and better management of machine hour load and a significant gain in the sector response time.

Nov 22, 2018

The South African Institute for Mining and Metallurgy celebrated its 95th anniversary with a banquet at The Carlton on Friday, 2nd June, 1989. This event was attended by 600 people, including the Presidents of AS&TS, constituent societies, and other kindred bodies, together with members and their guests. The guest speaker was Mr Muray Hofmeyr, Chairman of the Johannesburg Consolidated Investment Company Limited, who gave an interesting and thought-provoking talk entitled 'Will we still be the best in the year 2001'

Jan 1, 1989

By Richard L. Ash

A question that frequently arises during litigation concerned with accidents or alleged damages involving blasting is "were the explosives used according to the best known standards"" The question is not confined to only law suits, however, but also everytime poor blasting results occur. Unfortunately, general guidelines that can be used to define what may be considered as proper practice have not been established by any responsible body upon which to base a reliable Judgment; more often than not decisions are made primarily according to personal opinion.

Jan 1, 1975