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By Mazany, M. S.

THE Caletones copper smelter of the Braden Copper Co. is in the " Teniente" mining district about SO km. (49.7 mi.) southeast of Santiago, Chile. From the seaports of San Antonio and Tralparaiso, the property is reached via the Chilean State Railway (66-in. gage) to Rancagua, whence the Braden railroad (30-in. gage) leads to the smelting plant at Caletones, 60 km. away at 5100 ft. elevation, and continues on to the mine and concentrator at Sewell, at 7000 ft. elevation, 12 km. farther into the Andes. The smelting plant was completed and put into commission in February, 1922. At the start, it smelted daily 750 tons of concentrates produced at Sewell from 10,000 tons of ore; later, its capacity was increased to 900 tons of concentrates from 12,000 tons of ore per day; and it is now being increased to 1100 tons of concentrates from 15,000 tons of ore per day. The smelting plant production is governed chiefly by the

Jan 1, 1925

By D. Harrington

While apparently the hysteria with regard to silicosis and other occupational diseases has largely subsided and this subject is being more carefully considered and soberly judged, it would be poor policy for any employer to maintain that the storm has ended and that he can relax and revert to conditions as they were 5, 10, or more years ago. The fact is that the plan of paying occupational-disease compensation is now in its infancy and can be expected to grow rapidly. At present, while all of the States of the Union, including the District of Columbia and excepting only Arkansas and Mississippi, have compensation acts, only the following make provision for occupational diseases to some extent or in one way or another: California, Delaware, Connecticut, District of Columbia? Illinois, Indiana, Kentucky, Massachusetts, Michigan, Minnesota, Missouri, Nebraska, New Jersey, New York, North Carolina, North Dakota, Ohio, Pennsylvania, Rhode Island, Washington, West Virginia, and Wisconsin. Silicosis is compensable in one way or another in California, Connecticut, District of Columbia, Illinois, Kentucky, Massachusetts, Missouri, New York, North Carolina, North Dakota, Ohio, Pennsylvania, West Virginia, and Wisconsin, and possibly in other States. During the past few months, occupational-disease legislation (largely silicosis) has been considered in some form in Arkansas, California, Delaware, Idaho, Maryland, Kansas, Massachusetts, Michigan, Minnesota, Montana, Nebraska, New Jersey, Ohio, Pennsylvania, Tennessee, Utah and Washington. It will be surprising if comparatively comprehensive occupational-disease legislation is not on the statute books of nearly every State in the Union within the next 5 years. With this situation confronting him, the farsighted industrialist who has the interest of his organization at heart, if he has not already done so will immediately start to "put his house in order" by studying possible occupational disease hazards to his employees and promptly applying known remedial measures or attempting to devise such measures if none exist. Unquestionably, one of the most important of the surveys to be made relates to dust occurrence, as State laws on occupational disease are almost certain to contain provisions, on silicosis and, with almost equal certainty, the provisions of any State law are not likely to be particularly similar to those of other States.

Jan 1, 1938

By Jerry D. St. Clair

A multidisciplinary team of scientists and engineers at Wont has been working to understand heavy metal contamination of DuPont process waste streams and technologies for abatement of these metals. As part of this effort, an extensive study was made of a specific waste stream of importance in DuPont's environmental commitment. This 200 gpm stream contains 5-5000 ppm of nickel plus a variety of inorganic and organic constituents. The chemical complexity of the waste rendered conventional. alkaline precipitation ineffective, and only through the simultaneous application of analytical characterization, fundamental chemical understanding, and process engineering did effective technical approaches emerge. In this instance, ion exchange, sulfide precipitation, and caustic digestion ultimately proved successful in reducing the nickel to below the 1 ppm target. The results of this study will be presented, along with key learnings about the process of solving heavy metal contamination problems.

Jan 1, 1994

By S. Cagirici, Z. Öztürk, A. Hassanzadeh

Many flotation kinetics models have been studied in the literature. Their applicability was extensively investigated and argued in detail. However, model selection criteria were not adequately discussed from the statistical points of view. In this investigation, the kinetic behavior of a complex copper sulfide ore was studied in a mechanical Denver flotation cell focusing on flotation kinetics of chalcopyrite, pyrite and molybdenite. Different flotation kinetics models including nine common empirical models and four mathematical models namely Hill, Chapman (Sigmodial function), single rectangular (Hyperbola equation) and exponential were applied to the experimental data. In addition to assessment of the goodness of fit criterion for each model, a factor of model complexity was considered using information criteria (IC) (i.e. Bayesian information (BIC), low of iterated logarithm (LILC) and Akaike information (AIC) indices). The obtained results showed that the IC indices could simply manifest the best-fitted model to the experimental data. Whereas, the coefficient of determination values (R2) were relatively same for all models. By taking the R2 and model complexity criteria into account, the exponential model was chosen as the best representative mathematical model to demonstrate chalcopyrite kinetic behavior. However, Chapman model was selected as the best one for the flotation of pyrite and molybdenite. In case of the common first-order flotation kinetics models, fast and slow flotation kinetic model (Kelsall) was reasonably fitted the best to the given data of chalcopyrite. However, the gas/solid kinetics adsorption model was chosen as the best-fitted one for pyrite and molybdenite. Furthermore, it was found that mathematical models represent better results in association with flotation kinetic behavior of chalcopyrite, pyrite and molybdenite due to the consideration of more parameters in modeling. Finally, it was concluded that the IC indices must be applied to the process of model selection due to consideration of goodness of fit, complexity of a model and model consistency.

Jan 1, 2018

By C. H. Attwood

Introduction In presenting this paper on the water-power resources of the Province of Manitoba, it was considered that a brief resume of the power resources of Canada, of the power already developed, and its utilization in the industries 9f the country, would be of particular interest in showing the rapid progress that has already been made. Amongst Canada's national assets, water power occupies a foremost place because of the facilities it provides for the development of her other great natural resources. The rapid development of the mining, pulp and paper, and general manufacturing industries, and the concomitant growth in urbanization, with its numerous demands for domestic, commercial, and municipal service power, have combined to stimulate hydraulic development to a point surpassing even the most sanguine predictions of a few years ago. With the bringing into operation during 1928 of hydraulic turbines aggregating over 550,300 h.p., and of a further 378,400 h.p. in 1929, Canada's total hydraulic development at the end of 1929 amounted to over 5,700,000 h.p., and in this year, 1930, the active construction in hydro-electric plants throughout the country totals in excess of 1,600,000 h .p.

Jan 1, 1930

By H. P. Greenwald

For some years past the Safety in Mines Research Board of Great Britain has been making an intensive search for. materials that would be more efficient than rock dust and that could replace it wholly or in part as a moans of preventing the prorogation of coal-dust explosions in mines5/ In the course of this work several rock ducts and numerous inorganic compounds were tested. The results place incombustible substances in two main groups; (1) Those whose effect in suppressing the combustion of coal dust is proportional to their capacity for absorbing heat, and (2) those that shoo much higher effectiveness than would be expected from their heat capacity. The first group includes several inorganic compounds and materials commonly ground for use as rock dust, such as shale, gypsum, and limestone. Outstanding examples of the second group are compounds of the halogens6/ with the alkali metals,7/ especially potasium and sodium8/. British investigators term those salts "inhibitors" because it is assumed that their presence has a hindering or inhibiting effect on one or more of the chemical reactions that together constitute combustion. In other words, the action of an inhibitor is postulated as chemical rather than physical; theoretically, the effect is to prevent liberation of energy instead of to absorb energy already liberated.

Jan 1, 1940

By M Watson, A V. Engelbrecht, E Murray-Hayden

Whereas mine reconciliation is a well-established month-end process for most modern mining operations, the resource sector has yet to endorse uniform reporting factors against which model accuracy and metal recovery can be formally assessed. Logically, any comprehensive reconciliation framework should facilitate comparison between period reserve, mine and mill and production figures. Historically, Parker’s F Series ratios (Parker, 2012) are often used in some form by mine operators, although they are rarely shared externally, as formal definitions have yet to be accepted. This paper presents a structural extension to the reconciliation process, wherein resource ratios (R Series factors) are used to quantify the long-term impact of the information effect, together with dilution and ore loss. A case study from the El Limón Guajes (ELG) Mine Complex in Mexico is used to demonstrate how an R Factor Series can be implemented to facilitate operation optimisation, over and above conventional F Series reconciliation treatments. This approach is applicable to any mining operation.

Mar 22, 2022

By R. L. Minckler

PETROLEUM industry forecasts are constantly made and revised but are not in the nature of predictions. Particularly in the field of demand, many of the factors are far beyond control by the producing industry. Supply reacts on demand and demand reacts on supply. Competent economists in the oil business forecasted a year ago, on the basis of experience, that demand would now be at a much lower level than it is. This increased demand increased the price of crude oil and products, and in turn those increased prices have brought forth increased supply. A reduction in demand would lead to a reduction in supply. Shortages are now world-wide, and costs of secondary importance, so if there were extra supplies in California they would be moved into what are termed "unnatural markets." For example, Argentina is in the market today for California gasoline; that is an unnatural market because of the greater transportation distances from California to Argentina than from normal sources.

Jan 1, 1947

By W. H. C. SIMMONDS

The mining, metallurgical, and petroleum industries can be viewed as financial or as social institutions or both. The differences between these two conceptions of their businesses will influence their environmental 'and social actions. During the next 10-20 years western industry will be subject to a drop in the growth of a more highly educated labour force and to the emergence of holistic economics, new national goals, and a new ecological perspective. The profitability of the mining industry may therefore be influenced by the human side of its business to a greater degree. The increasing human, social, and environmental responsibilities can be discharged by improving the miner's equipment; by learning to look at situations through the eyes of all those involved; by developing common 'languages' which governments and the public can understand; and by mediating where feasible on the international scene.

Jan 1, 1978

By Gergely Markos

Uranium mill tailings represent a potential threat to the human habitat by containing large amounts of radioactive and chemically toxic substances in high concentrations. These: undesired components enter the human habitat in various pathways such as by erosion and water or air transport. The main objective of this investigation was to evaluate the actual movement and model the potential movement of contaminants by seepage of water from the tailings into the subtailings soil. This report represents various models of the movement of contaminants using both theoretical approaches and empirical evaluation of data available from other investigations. The data consist of field measurements and laboratory determi¬nations of major and trace cations, the dominant anions, pH, and Eh of moist solids, extracts, and waters from the tailings and surroundings. Evaluation and interpre¬tation of data were accomplished by using Eh-pH diagrams, various statistical methods and the WATEQFC computer program. Data analyses show that the critical area of investigating movement- is the interfaces between tailings and the external environment. The chemical differences at interfaces seem to result in a sink system for contaminants. The tailings-soil¬-water system shows extreme complexities because of chemical and physical hetero¬geneity of the system preventing the use of a single comprehensive model to represent real conditions. The validity of the simplifying assumption used has been shown and increasing complexity has been built into the models. Analogs of these models can be used for evaluation of similar systems.

Jan 1, 1981

By David Harrison

Exxon Minerals Company uses geostatistical techniques for ore resource evaluation of its mineral projects. These techniques provide the most reliable estimates of recoverable tonnage and grade and uniform and realistic confidence limits. A schema has been developed which categorizes the company's successive evaluation phases. Clear separation is intended between geostatistical estimates and other factors in project evaluation such as mining, metallurgy, and economics. Company management seeks consistent and reliable estimates for investment decision-making and to meet growing demands for disclosure of mineral assets.

Jan 1, 1983

"Investment in diamond exploration has been declining over the past decade, in spite of positive long-term industry fundamentals and a growing interest in diamonds as an investment category. The lack of new significant discoveries in recent years has eroded investor confidence, yet no new discoveries are possible without investment in exploration. Junior ‘mine finders’ have been the hardest hit. Their agility, tenacity, and appetite for risk are not sufficient to attract the funding required, even at the greenfield stage. Developing new discoveries into mineral resources can be crippling without solid financial support. Junior incubators could play a crucial role, especially at the project evaluation stage – but where are they? Alternatives to traditional funding mechanisms have become available, many still untested in the junior diamond exploration space. Valuable lessons can be drawn from the past and used to inform emerging new strategies. IntroductionDiamonds are the ultimate expression of love. Their ancient and timeless allure continues to influence consumer emotions and behaviours across continents, cultures and age groups. Analysts are predicting a sustained supplydemand shortfall in the years ahead which will trend diamond prices generally upwards. With positive long-term industry fundamentals, one cannot help but wonder why funding for diamond exploration and development projects is so scarce.Investment in exploration across commodities – including diamonds – has been declining for a number of years, reaching a historic eleven-year low early in 2017. The lack of major diamond discoveries in recent years has done little to strengthen the case for investing in diamond projects, yet no new discoveries can be made without investment in exploration.Global estimates of known carats in the ground stand currently at 2.5 billion carats, which equates to around 18 years of production at current levels of 140 million carats (mct) per annum. Sustainable replenishment of depleting diamond resources is possible only through the development of new discoveries. This is what junior explorers are best at – but they need investors to fund their evaluation activities from early in the project development continuum."

Feb 1, 2019

By Ralph B. Youtz

This paper describing mining methods at, the Eighty-Five mine of the Calumet and Arizona Mining Co., Valedon, N. Mex., is one of a series being prepared by the United States Bureau of Mines on mining methods, practices, and costs in the various mining districts in the United States. The Eighty-Five mine is in southwestern New Mexico, 3 miles southwest of Lordsburg, Hidalgo County (see fig. 1). The mine produces normally 7,000 to 8,000 tons per. month of silicious copper-gold-silver ore, and employs approximately 200 men underground and 40 on-the surface. Mining is done by shrinkage and cut-and-fill methods.

Jan 1, 1931

By S. M. Shelton

SINCE the Saar started. the real progress in scrap-metal recover is in the change of point of view regarding secondary metals. The tendency had been to regard scrap as the normal outgrowth of obsolescence, fluctuating somewhat from periods of depression to periods of prosperity. but nevertheless an unwieldy economic factor more to be contended with than embraced. Now, metals above the ground are being looked upon as semi-permanent reserves or stock piles in various stages of repeated use or revolving life cycles. The change in point of view is due to the forced realization that domestic supplies of new metals are limited and many foreign sources are at least temporarily closed. The stock piles must be cultivated. The reserves must be made more nearly permanent. Steps are being taken : (1) develop methods for recovery of scrap metals heretofore not recovered, and (2) restrict strategic metals to uses ensuring a large percentage of re-use, which in turn means substitute materials in the dissipative uses.

Jan 1, 1942

By J. R. Giegerich

"IntroductionMINING operators in common with other operators are confronted today with two serious problems, shortage of experienced workmen and rising costs. The following review of practices at the Sullivan mine of The Consolidated Mining and Smelting Company of Canada, Limited, outlines certain measures that have been responsible, during recent years, for minimizing the effect of these two problems. The paper is divided into three main sections:( 1) Training programmes and job studies( 2) Improved mechanization and equipment( 3) Large-scale methods of operationTraining Programmes and Job StudiesJob TrainingJob training courses were introduced at Cominco immediately after the last war and proved to be a great benefit to the operations. There were three courses given, Job Instruction Training, Job Safety Training, and .Job Relations Training. These were spread over a period of two years and were taken by all operating supervisors and some key operators.The courses were introduced by a trained instructor from the British Columbia Department of Labour. This man trained twelve of our employees as instructors by giving them an intensive one-week course. Similarity between the three courses was such that the instructors trained in the first one were very readily trained for instruction in the two succeeding courses."

Jan 1, 1952

By A. D. MacPhail

The Highland Valley Copper partnership was formed in July 1986 and was the logical result of a mine with a large ore reserve but no adequate mill, and a mine with a large, modem mill but dwindling ore reserves. The original partners -Cominco and Lornex -were joined in January 1988 by Highmont Mining Co. which contributed a two-line concentrator. During 1988/1989, the Highmont mill was moved 7.5 km to adjoin the Lornex mill, forming what is now called the Highland mill, with a current nominal capacity of 130 000 tonnes per day. The mine is located 220 km northeast of Vancouver, British Columbia and is close to four communities in which personnel make their home: Logan Lake, Merritt, Ashcroft, and Kamloops. The map in Figure 1 2.2 shows the general area. Kamloops is a major service centre and is serviced by two railways, two major roads and a regional airport.

Jan 1, 1993

By Marcelle A. Hauseux

"The Turgeon Lake granite lies 5 miles north of Baie Johan Beetz, Quebec, at the eastern margin of the Grenville Province. The rocks are classed as granites, granulites, quartzites, biotite schists and gneisses, and amphibolites. The granite's uraniferous character is manifested by phosphuranylite, uraninite, and metamict .zircons associated with magnetite. Field anomalies occur in irregular pods, conformable with the tectonic foliation, in bands roughly paralleling sedimentary bedding. Associated features diagnostic of uraniferous granite are smoky quartz, brick-red feldspar, magnetite and a coarse to pegmatitic grain size. The granite is chemically and physically heterogeneous. Metasediment-granite contacts are diffuse or sharp, and usually conformable to bedding. The regional foliations within all rock types are coherent, and sedimentary structures are often preserved within both metasediments and granite. Autometasomatism probably was a strong granitization agent.A uranium reconcentration into fold-axial zones from original sediments which have been highly granitized during at least two phases of folding is suggested from the available data."

Jan 1, 1977

By K. D. Genn, A. Mucha

This paper deals with Hilton Mines' approach to the maintenance of wear items such as truck boxes, shovel buckets, tractor pads, crawler sprocket idlers and the drop-ball. Each will be given a brief. description as to application, design, kind of materials involved and type of wear. The maintenance procedure is then outlined in terms of materials used, preliminary preparation, and welding and machining practices. The service history of new and re-paired items and the relative economics of repair vs replacement will then be presented.

Jan 1, 1969

By Harry Sutcliffe

THE PROBLEM Two and a half years have gone by since the December, 1976 Civil Engineering article on subway costs caused such a furore. What has happened in this interval? Even after discounting the crushing inflation rate, costs are still increasing, and there is no sign of a turndown, even in the rate of increase. Some steps outlined in the article have been taken. In April this year, the first D.O.T.-sponsored Peer Review Group, made up of managers of other transit properties, met in Boston to review MBTA's $500 million Red Line Extension-Northwest for cost effectiveness. While the impact of a review at the end of the design phase, with substantial segments under contract, cannot be as effective as a review early in the design phase, it is nevertheless a start. This first meeting will be followed by a review of Boston's Orange Line relocation, the final design for which is just underway. In the industry at large two facts are evident: 1. We are failing to reduce underground construction costs. 2. Underground construction is in danger of pricing itself out of the market place. It has always been a greater challenge to design a Chevvy than to design a Cadillac, but it is the Chevvy we need today. Much attention has been focussed in the past on engineering design in the narrow sense: areas such as ground loading conditions and concrete design. This paper will attempt to make the case that costs in urban underground construction are primarily outside the area of structural

Jan 1, 1979

By William O. Vanderburg

This paper 3/gives the results of a reconnaissance of mining districts in Clark County, Nev., made from November 18 to December 22, 1936, and from February 9 to March 8, 1937-in all, 63 days. While the field work Was being done, virtually all of the mining districts in the county were visited and many data on active and inactive properties were obtained. The report covers the locations of the various mining districts, the nature of the deposits, information on past operations, current activity, and general data likely to be useful to operators, investors, and others interested in mining. The geology of the deposits is discussed only briefly. The principal metal-mining districts in the county are Goodsprings, Eldorado, and Searchlight. The zinc-lead ores of Goodsprings have been the most important economically, followed by the gold-silver ores of Eldorado and Searchlight. In the industrial-mineral field, gypsum, limestone, silica sand, and borates are the principal products. Metal mining in the county is characterized by numerous small operations and the ores are either milled locally or shipped to distant smelters.

Jan 1, 1937