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By D. H. C. Wilton, W. A. Sears

"Abstract-The 682.8 ± 1.6 Ma Tickle Point Group consists mainly of rhyolite flows and tuffs with- in the Avalon Zone of the Appalachian Orogen in Newfoundland. Stratabound massive sulfide mineralization, consisting of pyrite, sphalerite, chalcopyrite and galena, occurs at the Winter Hill prospect, where a lower pyritic, Cu-rich zone and an upper Zn-Pb-rich zone are hosted by a carbonate-calc-silicate lens. At the Frenchman Head prospect, stringers of pyrite, minor sphalerite, chalcopyrite and rare galena are hosted by felsic volcanic rocks of the Tickle Point Group .Base metal ratios, metal zonations and the overall stratigraphic framework suggest that these sulfide occurrences represent volcanogenic massive to semi-massive sulfide mineralization (stringer type at Frenchman Head). As such these prospects represent the only known VMS occurrences within the Avalon Zone of Newfoundland. Pb isotope data indicate that galena from the Winter Hill prospect is less radiogenic and older than galena from Dunnage Zone occurrences, and suggest that the Winter Hill mineralization formed in an environment tectonically distinct (exotic) from the Dunnage Zone."

Jan 1, 1996

By E. Oshima

The only one reverberatory furnace smelting in Japan has been alive in Onahama Smelter, Onahama Smelting and Refining Company. The fuel for the reverberatory furnaces had been changed from bunker C-oil to mainly coal and partially waste tires to reduce the energy cost. The steam, recovered by the waste heat boilers of the reverberatory furnaces, has been utilized fully for the power generation to save the purchase power. Copper concentrate has been smelted also by injection through tuyeres in the P.S. converters since 1983. The amount of concentrate, treated in the converters, was increased by the construction of small oxygen plant in December, 1990. In the paper, the current practice and improvements in the reverberatory and converter operations are described.

Jan 1, 1993

By Raymond E. Sandiford

"The redevelopment of the World Trade Center (WTC) provided an opportunity for the Port Authority of NY and NJ to complete a long sought underground connection between all of Lower Manhattan’s transit lines, the World Trade Center and the World Financial Center (WFC) (Figure 1). Creating this connection was a challenge because the WFC lies west of the heavily trafficked Route 9A, also known as West Street. The previous connection was a bridge that required pedestrians to make significant level and directional changes to navigate the crossing. The positioning and elevation of the Route 9A pedestrian tunnel was established to provide pedestrians with a clear, single level, climate controlled corridor from the new WTC Transit HUB to escalators leading into the WFC Winter Garden.As the most direct link to the WFC, tens of thousands of people a day will use the pedestrian corridor. To accommodate this large number of pedestrians and provide an obstruction free passage, the tunnel has a clear width of 50 ft (15.2 m). Although only 250 ft (76.2 m) long, that short length presented many technical challenges.Here I describe how the challenges were overcome during the construction. However, some of the truly problematic issues arose from coordinating the phasing of this project with adjacent construction activities at the WTC, the reconstruction of Route 9A, and the WFC’s redevelopment program. The limited access to the excavation areas and confined site logistics were further complicated by having to maintain six lanes of traffic on Route 9A at all times. The efforts were so intertwined that, well into the underpass construction, the Port Authority Construction Department decided to merge a portion of that work into the WFC redevelopment."

Jan 1, 2012

By A. D. Pittuck

Refractory minerals .containing uranium and columbium have been successfully treated at Queen's University, Kingston, to produce high-grade concentrates. Recoveries of over 90 per cent of the uranium and columbium have been obtained when treating concentrates containing euxenite, fergusonite, betafite, and pyrochlore. The processes ?consisted -of leaching the columbium with hydrofluoric acid, and the uranium with nitric acid, sulphuric acid, or sodium carbonate solutions. The leach liquors were extracted with organic solvents from which the values were stripped and precipitated, producing final products assaying 45 to 55 per cent Ob2O5 and 60 to 70 per cent U3Os.

Jan 1, 1958

By David P. Kimball, Dalva L. Moellenberg

On May 21, 1990, EPA released its Strawman II draft program for mining wastes. It proposes to expand RCRA regulation of mining operations to include materials other than wastes. Strawman I1 would establish strict standards for the states to follow, rather than technical guidance. It proposes to establish performance standards; design criteria; monitoring requirements; and corrective action, closure, post-closure, and financial assurance requirements. It suggests "pollution prevention" concepts for mining operations. This paper explores the Strawman II proposals, particularly the technical criteria, and addresses several of the important concerns raised by industry.

Jan 1, 1991

Jan 1, 2004

By Hairong Zeng, Matthew Baumann, Shahram Tafazoli, Edmond Chow

Measurement of rock fragmentation has evolved from a completely subjective and manual process to a statistically objective and semi-automated process. However, ultimately, the vision is to achieve a statistically representative and fully-automated process. From the blast optimization perspective, it is critical to receive reliable rock fragmentation results quickly to incorporate into the planning of subsequent blasts. Since manual rock fragmentation measurement methods tend to be time consuming, a fully-automated method is the practical way to meet these requirements.

Jan 1, 2012

By Mike Higgins

"The purpose of mining and its related industries is the removal of, and usually the subsequentprocessing of, material from the earth. This includes mining for minerals, quarrying for stone, and civilexcavations. Where this involves rock, the most common method is to fragment the rock by blasting. "

Jan 1, 1997

By Hirsch H. H.

Further discussion at the North of England Institute of Mining and Mechanical Engineers' general meeting held in Newcastle-upon-Tyne, 3rd June 1916, on the paper published in Trans. I.Min.E., vol.LI, 1916, p.61-71, comprised the author's written reply to comments at the April meeting

Dec 1, 1916

By Robert E. (Bob) Brown

Magnesium was discovered by Davy in 1808. The production processes as they exist are not economically competitive with aluminum The electrolytic magnesium process is divided into two steps; one to make the MgCh feed and the other to apply large amounts of electric current to dissociate the feed into magnesium (450 g) and chlorine (1200 g). The production of fuJIy anhydrous, pure cell feed is a major problem Recently, there has been a growth of thermal processes, mainly the Pidgeon silicothermic production process using FeSi to reduce dolomite in horizontal retorts. Pechiney has a large vertical electrical furnace process that also uses FeSi to reduce calcined dolomite in a molten bath containing alumina. Work is proceeding to develop new or modified processes that will greatly improve magnesium production. The present methods and the research and R&D will be reviewed in this paper.

Jan 1, 2001

By Ángel Nuñez-Meza, Juan Alfaro-Bernedo

La intención del trabajo reportado en este artículo es la de superar las limitaciones que conlleva no trabajar con modelamiento previo, base de datos y un enfoque sistémico. En atención a esta idea, el estudio desarrolló un software para dos circuitos (directo e integral). Como resultado, se recomienda desarrollar un software integral de toda la planta concentradora —chancado, molienda, flotación y eliminación de agua— con diferentes tipos de circuito, en un solo sistema (enfoque holístico); además de migrar a un modelo de servicio en la nube, con el objeto de poder contar con completa disponibilidad.

Sep 30, 2019

By J. W. Butwell

Anaconda has been active In the Bingham mining district near Tooele, Utah since 1914 when the company acquired International Smelting & Refining Co. Over the years both custom ores and complex Pb-Zn-Cu ores from the district were milled and smelted at International. In 1948 Anaconda acquired the property that covers the present Carr Fork ore body. Since that time active exploration took place in the 50's followed by detailed geological evaluation in the 60's. Convinced that high grade Cu deposits would be found at depth, a deep drilling program commenced in the late 60?s, with intersection of the ore zone in 1969. Following extensive deep drilling in the early 70?s, a feasibility study was conducted in 73-74 with board approval given Sept. 6, 1974. The 9,000 t/d mine-mill complex was budgeted at $217 MM over a 5 year schedule with start-up in Sept., 1979. The following discussion includes the concentrator and surface facility portion of the budget or approximately $60 MM of the scope. Special emphasis will be made on equipment selection and layout.

Jan 1, 1980

By F. G. Schwartz

The Bureau of Mines developed a rapid and precise method for predicting storage stability of motor gasolines. This method resulted from the investigation of many analytical techniques as well as a study of fuel composition and fuel component gum-forming mechanisms. The first section of this bulletin discusses the development of the prediction test through its several phases, including revision of the standard 110° F storage test; attempts to develop a modification of the ASTM D525 induction bomb test; and the ultimate abandonment of this procedure with the adoption of the 16-hour oven test that was both precise and rapid. The second section comprises a discussion of further studies of fuel com- position, including the reactivity of certain sulfur compounds and hydrocarbons to form gum. The compositions of various gums and inorganic deposits are reported in terms of elemental analysis and spectroscopic examinations. The reactions of tetraethyllead with selected hydrocarbons are also reported.

Jan 1, 1972

By Manara Nogueira Quintino

No processo de produção de ferro e aço, uma grande quantidade de resíduos é gerada. Esses resíduos e coprodutos contêm consideráveis quantidades de ferro e carbono, que podem ser reaproveitados, ajudando a reduzir a poluição ambiental que pode surgir devido ao descarte inadequado. Este trabalho tem como objetivo avaliar o potencial energético contido em um resíduo siderúrgico, quando misturado à biomassa. Por meio de análise termogravimétrica e cinética (método Coats – Redfern) amostras com diferentes proporções de resíduo metalúrgico, biomassa de capim elefante e carvão vegetal foram estudadas. A amostra com menor tamanho de grão e maior quantidade de resíduo foi a que apresentou melhor perda de massa ao final do experimento, apesar de não ter apresentado o melhor resultado antes da faixa isotérmica do experimento. Contudo, a quantidade de capim elefante se mostrou relevante na performance da queima.

Oct 30, 2017

Descriptions of the following awards and lists of recipients through 1957 may be found in 1957 AIME Directory Recipients since that time are as follows JAMES DOUGLAS GOLD MEDAL 1958-J Roy Gordon "For distinguished contributions to process metallurgy in the field of smelting and refining of nickel, and metallurgical improvements in nickel recovery " 1959-Clyde Williams "For outstanding contributions in nonferrous metallurgy partic¬ularly through stimulating research and interest in the basic metallurgy and the use of both the common and the less common metals " WILLIAM LAWRENCE SAUNDERS GOLD MEDAL 1958-Willlam Jesse Coulter "For his distinguished achievement in contributing in general to the success of Climax Molybdenum Company, and, in particular, for developing mining practices of the Climax Mine "

Jan 1, 1959

By R. H. Wightman, C. D. Chandler, P. B. Nalle

SURFACE quarrying at the Crestmore Div. of Riverside Cement Co. in California was started in 1909. In the early 1920's it was considered that these deposits were nearly exhausted for the equipment available at that time, and in 1927 the company began a block caving system. This mine continued operating until February 1954. In 1941 trucks and crawler-mounted shovels had reached a stage of development that permitted reopening the quarries in conjunction with the underground mine. In 1948 surface reserves and the well developed limestone of the caving system neared depletion. To go deeper with the caving system was unattractive because of the economics, changes in physical structure of the rock at depth, and the perched water table

Jan 4, 1957

By Tronson K

Improvements in technology do not necessarily lead to higher profits: the benefit of lower costs can be captured by coal buyers, governments and workforce rather than by the colliery operators. The economic impact of longwall mining in Australia has been critically assessed to provide lessons for the future. For a variety of reasons, companies investing in longwall equipment in the past five years have generally not achieved an adequate return on the funds invested. The effect of technological innovation must be examined in the light of competitive forces operating in the market. Projections of cost reduction trends in the coal industry have been applied to a world cost model to provide a picture of the coal industry in the year 2000.

Jan 1, 1988

By Michael J. McGuire

Rostoker, Inc. has developed a process to smelt solid hazardous/non-hazardous inorganic wastes. Near seven hundred experiments were performed. Actual industrial wastes as well as reagent grade chemicals were used. By mixing a multiplicity of these wastes to proper formulations, then furnacing them, it was determined that saleable end products could be reclaimed; metal, fume and slag. The slag, due to its siliceous structure was tested to be leach resistant (40 CFR). This formed the essence of our patent, #5,180,421 "Method and Apparatus for Recovering Useful Products from Waste Streams". What is unique is that a HTMR (High Temperature Metal Recovery) process has been developed that can treat a multiplicity of wastes within the same furnace. The discussion will include a list of waste streams we have treated, details of proper waste formulation and experimental results.

Jan 1, 1994

By William Petruk

The primary requisite for a successful extractive metallurgy operation is to grind an ore fine enough to liberate the minerals so that they can be concentrated, or to expose mineral surfaces so that the minerals can be leached. The ease or difficulty of liberating or exposing the mineral grains is dependent upon the mineral textures such as grain size, crystallinity and bonding between mineral grains. In particular, mineral grains with straight grain boundaries and a weak bonding to other minerals are easily liberated and readily concentrated into high grade concentrates. In contrast mineral grains that have re-entrant boundaries and are strongly bonded to their neighbours are not easily liberated and will not produce high grade concentrates, even with regrinding. Similarly, inclusions that occur along fractures and grain boundaries can be readily exposed and leached. Whereas minute random inclusions in large grains will not be liberated or exposed unless they occur along planes of weakness.

Jan 1, 1995

By K. C. Sole

In most copper solvent-extraction operations, an important consideration in choice of extractant is the requirement for high selectivity of copper over iron. Ester-modified aldoxime extractants presently offer the best Cu:Fe selectivity. In some plants, however, the process feed liquors contain significant amounts of manganese but little iron. Although manganese is not chemically extracted by oximes, trace amounts are carried over to the electrowinning circuit by physical entrainment. This may result in anodic oxidation of manganese which, in turn, can cause oxidative degradation of the organic phase when returned to the solvent-extraction circuit in the spent electrolyte. Many of these operations prefer to operate with higher levels of iron reporting to the advance electrolyte, as appropriate control of the Fe(II)/Fe(III) couple will ensure that manganese remains in the benign Mn(II) form. A new reagent, LS 4202, designed by Cytec, now offers the possibility of tailoring the iron co-extraction, so that appropriate Cu:Fe selectivity can be achieved in the solvent-extraction operation to maintain an electrolyte Fe:Mn mass ratio of >10:1, while retaining the other benefits offered by ester-modified aldoximes. The results of an integrated solvent extraction-electrowinning pilot-plant trial are presented, in which the performances of the conventional extractants ACORGA® M.5774 and LIX® 984N are compared with LS 4202. The Cu:Fe selectivity is demonstrated, along with results on the transfer of other impurities to the advance electrolyte.

Jan 1, 2007