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Apr. 26-May 11, Liege International Fair, Liege, Belgium. May 4-8, Electrochemical Society, Inc., Spring meeting, Benjamin Franklin Hotel, Philadelphia. May 5-6, National Air Pollution Symposium, Huntington Hotel, Pasadena. May 5-7, American. Mining Congress, coal convention, Netherland Plaza Hotel, Cincinnati. May 6-9, Scientific Apparatus Makers Assn., annual meeting, Edgewater Beach Hotel, Chicago. May 9-10, AIME, joint meeting, Industrial Minerals Div. and Metals Branch, Davenport Hotel, Spokane, Wash. May 11-14, American Institute of Chemical Engineers, Atlanta Biltmore Hotel, Atlanta. May 17, AIME, Chicago Section, President's night dinner dance, Shoreland Hotel, Chicago. May 27, AIME, Morenci Subsection, Longfellow Inn, Morenci, Ariz. June 2-4, Chemical Institute of Canada, annual conference, Montreal. June 4-14, Mechanical Handling Exhibition and Convention, Olympia, London.

Jan 1, 1952

By C. G. McLachlan

Professor H.E.T. Haultain: To me from time to time the urge comes to say the agreeable thing as well as the disagreeable in commenting on the work of others. It is a prerogative of age. I don't apologize. To myself I justify my action as based on a long experience of the matters with which I deal, and I like to tell myself that I have a certain responsibility in such matters on account of my detached position. This Noranda article is a very fine contribution concerning Canadian milling, and I am surprised that no word of commendation or thanks has appeared concerning it in the BULLETIN. There is altogether too much written in these days by men rushing into print, concerning laboratory work, that has not been tied into, nor has resulted in application in the field. The authors of this paper have not rushed into print. The preparation of this paper was evidently an uncongenial task. If the authors had been that way inclined, it could have spread over several lengthy papers. It is an important article because it represents an enormous amount of work in the laboratory and the mill, extending over a period of sixteen years, and resulting in fine metallurgical and economic results with a very difficult and involved problem. It is a fine article because it is so well prepared and presented. It deals with an unusual ore condition, but there is much in it of use to every cyanide millman. It leaves very little room for criticism, though there may be differences of opinion in regard to some of the chemistry phases with which I am not conversant. I am struck by the enormous amount of persistent, painstaking, conscientious research work involved, and in the careful, sincere way in which the methods and difficulties have been described. Persistence and sincerity are the key note of the effort. It should have a good educational effect on the rising generation of millmen, and it should continue for long as a work of reference, and a spur to others. There has been an important by-product, the training and development of the young men engaged in the work. Three of them became superintendents of important mills. One was sought for important work in Africa, another has joined a large research organization in the United States.

Jan 1, 1946

By R. B. Gilmore, Lewis W. MacNauhgton

The North Texas district, as' herein defined, includes the counties of Archer, Baylor, Clay, Cooke, Foard, Hardeman, Knox, Montague, Wichita, and Wilbarger. This area covers generally the crest and south flank of a system of buried mountains known as the Red River uplift. The oil and gas accumulations along this feature are in traps, which, although localized by structures incident to the regional uplift, usually are modified by stratigraphic changes in the sediments. Excepting those in southeastern Baylor, southern Archer, and southwestern Clay counties, all the fields within the district are on this Red River uplift. These exceptions, which have the same type of oil and gas accumulation as the other fields, are on the extreme north end of the Bend arch, which is a broad anticline plunging northward from the Llano uplift in central Texas to Archer County. The larger part of past oil and gas production has come from Pennsyl-vanian strata, with less important amounts from the Permian, and minor but increasingly important quantities from the Ordovician. Developments during 1942 Approximately 500 wells were drilled in the district during 1942, in contrast with some 1600 wells drilled during 1941, and only some goo oil wells were completed, a decrease from 1941 of more than 10 per cent in the number of successful drilling operations of the total wells drilled. Production increased slightly over the previous year in spite of a decrease in the number of producing wells. The average depth of discovery wells was some 600 ft. deeper than in 1941. Although more discoveries produced from horizons above the base of the Strawn series than those below the Strawn, the deeper horizons, including the Bend series of the Pennsylvanian, the Mississippian limestone, and the Simpson and Ellenburger of the Ordovician, furnished most of the addition to oil reserves. The largest single addition to the reserves was again in the Ellenburger formation in the K. M. A. field. During the year 47 wells were completed, bringing the total developed acreage in this horizon to some 5450 acres. The most active area was Montague County, in which eight fields, or potential fields, were discovered although only 39 oil wells were completed. K. M. A: Pressure Maintenance Satisfactory progress was made by the K. M. A. Pressure Maintenance Association in 1942, At the end of the year, 100 wells were being used for input and total monthly volume of gas returned to the reservoir reached a high of 430,971 M cu. ft. in December, with an input ratio of 587 cu. ft. of gas returned for each barrel of oil produced during the month. This represents a utilization of 50 per cent of the gas available for return during that month. Comparison of the present average bottom-hole pressure by means of a decline

Jan 1, 1943

By R. B. Gilmore, Lewis W. MacNauhgton

The North Texas district, as' herein defined, includes the counties of Archer, Baylor, Clay, Cooke, Foard, Hardeman, Knox, Montague, Wichita, and Wilbarger. This area covers generally the crest and south flank of a system of buried mountains known as the Red River uplift. The oil and gas accumulations along this feature are in traps, which, although localized by structures incident to the regional uplift, usually are modified by stratigraphic changes in the sediments. Excepting those in southeastern Baylor, southern Archer, and southwestern Clay counties, all the fields within the district are on this Red River uplift. These exceptions, which have the same type of oil and gas accumulation as the other fields, are on the extreme north end of the Bend arch, which is a broad anticline plunging northward from the Llano uplift in central Texas to Archer County. The larger part of past oil and gas production has come from Pennsyl-vanian strata, with less important amounts from the Permian, and minor but increasingly important quantities from the Ordovician. Developments during 1942 Approximately 500 wells were drilled in the district during 1942, in contrast with some 1600 wells drilled during 1941, and only some goo oil wells were completed, a decrease from 1941 of more than 10 per cent in the number of successful drilling operations of the total wells drilled. Production increased slightly over the previous year in spite of a decrease in the number of producing wells. The average depth of discovery wells was some 600 ft. deeper than in 1941. Although more discoveries produced from horizons above the base of the Strawn series than those below the Strawn, the deeper horizons, including the Bend series of the Pennsylvanian, the Mississippian limestone, and the Simpson and Ellenburger of the Ordovician, furnished most of the addition to oil reserves. The largest single addition to the reserves was again in the Ellenburger formation in the K. M. A. field. During the year 47 wells were completed, bringing the total developed acreage in this horizon to some 5450 acres. The most active area was Montague County, in which eight fields, or potential fields, were discovered although only 39 oil wells were completed. K. M. A: Pressure Maintenance Satisfactory progress was made by the K. M. A. Pressure Maintenance Association in 1942, At the end of the year, 100 wells were being used for input and total monthly volume of gas returned to the reservoir reached a high of 430,971 M cu. ft. in December, with an input ratio of 587 cu. ft. of gas returned for each barrel of oil produced during the month. This represents a utilization of 50 per cent of the gas available for return during that month. Comparison of the present average bottom-hole pressure by means of a decline

Jan 1, 1943

By Elnaz Saminfar, Jae Bateman, Eric Westergren, Mark Trim

This paper presents a case study of two major Australian infrastructure projects that used digital engineering to facilitate design delivery: WestConnex Project (Rozelle Interchange), and Sydney Metro West (Eastern Tunnelling Package). The paper presents project overviews and building information modeling (BIM) execution and focuses on modeling techniques, software utilization, data management strategies and how the digital models helped the design-build team mitigate impacts to schedule by identifying clashes between disciplines before the execution of work. Finally, it demonstrates the positive and transformative impact of digital engineering on the design and construction of large underground infrastructure projects and highlights its role in asset management throughout the project lifecycle.

Jun 23, 2024

Andes Copper has an old camp and a new camp, both isolated until recent road improvements. The old camp is at Potrerillos and the new one at El Salvador, 25 road ,miles away. The company was incorporated in 1916 and the first mine, concentrator, leaching plant, smelter and town were built in the succeeding twelve years. The first blister copper was poured on January 24, 1927. Economic conditions determined the long development period but the end result was the design and construction of a mining complex that was all of a piece, unlike the piecemeal additions to El Teniente and Chuqui. The mining episode at Potrerillos came to an end in 1960 when the ore at La Mina became exhausted and the new mine, El Salvador was brought in. Both of these ore deposits come within four hpundred feet of the surface and had they been developed within the last five years might reasonably have been brought in as open pit mines. However, that is conjecture, and as it stands the operation at La Mina was so ideal for the mining method selected, blockcaving, it became a classic for the textbooks. On the other hand, El Salvador has turned out to be a blockcaving mine to test an engineer's skill. In mining the copper deposit at Indio Muerto mountain, there are ground conditions of every conceivable type. Tunneling in one section, the back can cave like sized pea gravel and only spiling can hold it; in another heading only the lifters are shot but often the rest of the round will sit down in one piece; elsewhere the bottom squeezes up and closes the drifts; and contrary to all other locations, there are sections where the block can be undercut without support. Today the scope of operations at Andes extends from mining to electrolytic copper. Ore is mined at El Salvador and the concentrator is also situated there. Concentrates pipelined 14 miles to Llanth, the water decanted, and then it is hauled by rail 40 miles and 5500 ft higher to the Potrerillos smelter and refinery. Potrerillos and El Salvador are respectively 90 and 70 miles from the port of

Jan 11, 1969

By E. Vahidi

In this study, a hydrometallurgical treatment involving solvent extraction of zinc using D2EHPA (di-2-ethylhexyl phosphoric acid) has been investigated to recover zinc from an industrial zinc leach residue. The residue was leached with sulfuric acid producing leach liquor which was subjected to solvent extraction for enrichment of zinc and removal of impurities. Operating variables for the zinc extraction process, such as pH of the mixed solution (0.5~5.0), concentration of D2EHPA (5%~40%, w/w), temperature (25~60°?C), A/O volumetric phase ratio (1/2~4/1), concentration of tri-butyl phosphate (TBP) as modifier (3%~7%, w/w), concentration of NaR2RSOR4R in aqueous phase (0.05M, 0.1M, 0.2M) were also studied. Practically all zinc was extracted from the aqueous solution at pH 2.5 with 20% w/w D2EHPA in kerosene. At this operating condition, zinc could be extracted at one theoretical stage at A/O phase ratio of 1/1, as calculated by the McCabe-Thiele method.

Jan 1, 2014

By Charles A. Schffer

Several months ago, some specimens of the minerals occurring at the Etta tin mine, Dakota, were received at the laboratory of the Cornell University. On examining the heavy brownish-black portion, which I presumed was the tin-stone, I was surprised to find only a faint indication of tin. Further investigation showed the mineral to be tantalite. On searching carefully all the fragments received, a considerable quantity of that mineral was found, and only a single streak of cassiterite, which was attached to a mass of spodumene. Another lot of specimens, from the same locality, consisted of

Jan 1, 1885

By V S. T Ciminelli

This work aimed at evaluating the acid rock drainage (ARD) potential of five samples of a Brazilian gold sulfide mine in a decommissioning process. Three of the most traditional ARD prediction techniques, Standard Acid Base Accounting (Std ABA), Modified Acid Base Accounting (Modified ABA), as static methods, and humidity cells as a kinetic method were tested. Both the Std ABA and the Modified ABA results indicated an acid generation potential for some of the studied samples. In the other cases the results were inconclusive. The five samples were then submitted to humidity cell tests during 27 to 30 weeks. At the end of the period, the leachate pH was stabilised in a range from 3.4 - 4.1 (four samples) to 5 (one sample). The presence of relatively high levels of sulfate and dissolved metals was detected throughout the operation, specifically, Ni and Zn, and less frequently, As. These findings are discussed with the help of the samples mineralogy and Eh-pH diagrams. The results obtained in this investigation indicated potential environmental risks of this mining area. In this particular case, the kinetic tests were shown to be essential to the identification of the samples ARD potential.

Jan 1, 2003

The Institute conducts jointly with the American Society of Civil Engineers, 'American Society of Mechanical Engineers and American Institute of Electrical Engineers, certain activities as listed below, and is joint owner with them if certain properties. United Engineering. Trustees, Inc. When Mr. Carnegie made his gift which made possible a home for the engineering societies, a separate corporation was organized to act as a holding company and to manage the common property. This was long known as the United Engineering Society but the name has now been changed to one which more nearly reflects the real function of the corporation. It holds title to the Engineering societies Building and to various funds placed in its charge and is managed by a Board of Trustees of which three are chosen by each of the four societies, American Institute of Mining and Metallurgical Engineers, American Society of Mechanical Engineers, American Institute of Electrical Engineers and American Society of Civil Engineers, which own equal and undivided interests in the property. The land and building cost two million dollars. The interest of each of the Founders societies, aside from especial trust funds, is now valued at $493,352. The A. I. M. E. trustees are Arthur S. Dwight, J. V. N. Don and George D. Barron. The President of the Board is Francis Lee Stuart and the Secretary, Alfred D. Flinn.

Jan 1, 1929

The Institute conducts jointly with the American Society of Civil Engineers, American Society of Mechanical Engineers and American Institute of Electrical Engineers, certain activities as listed below, and is joint owner with them of certain properties. United Engineering Trustees, Inc. When Mr. Carnegie made his gift which made possible a home for the engineering societies, a separate corporation was organized to act as a holding company and to manage the common property. This was long known as the United Engineering Society, but the name has now been changed to one which more nearly reflects the real function of the corporation. It holds title to the Engineering Societies Building and to various funds placed in its charge and is managed by a Board of Trustees, of which three are chosen by each of the four societies, American Institute of Mining and Metallurgical Engineers, American Society of Mechanical Engineers, American Institute of Electrical Engineers and American Society of Civil Engineers, which have equal and undivided interests in the property. The land and building cost two million dollars. The interest of the Founders societies, aside from especial trust funds, is now valued at $1,987,793. The A. I. M. E. trustees are William H. Bassett, H. G. Moulton and R. M. Roosevelt. The President of the Board is Harold V. Coes and the Secretary, Alfred D. Flinn.

Jan 1, 1934

The above paper is an important contribution to the field of physicochemical studies in ferromanganese production. The authors are to be congratulated on the well planned and competently executed experimental work and on the interpretation of the data. Although the paper is essentially descriptive, the results lend themselves to thermodynamic interpretation (but in such a complex system as that studied this cannot be done rigorously), as well as to an examination of the probable reduction mechanisms that operate at various stages.

Jan 1, 1979

By Alfonso W. Ovalle, Héctor R. Albornoz

INTRODUCTION The El Teniente Mine of Codelco-Chi le has extracted 588 mil lion tons of ore in its 77 year history for a total copper output of 8.800.000 tons. The mine production has been obtained mainly by traditional block-caving where grizzlemen using a hand held lever send ore through long-raises to load trains. At present the mine is about to introduce mechanized block-caving using LHD equipment to extract the primary rock. This paper describes this method which will be tested starting next month by caving an 11.000 square meter block. THE PRIMARY ROCK PROBLEM The secondary enrichment sulfides of the El Teniente ore body have characteristics which makes a standard unmechanized block-caving practice very successful. In the 60's parts of blocks encountered primary ow in the Teniente 1 and Sub-13 levels which proved to be extremely hard to extract. These foretold the obstacles that arised in the central part of the Teniente 4 level. Preparation of a completely primary 8.100 square meter block started in 1970. Its undercutting was completed by the end of 1972 and by 1973 the problem of mining the primary rock was clearly visualized. The numbers below describe the difficulties in mining this block: -Long-hole drilling rate is 90 m (270 ft) per shift in secondary rock and 37 m (110 ft) in primary. - Undercutting which is completed in 9 shifts in secondary took 180 shifts in the primary block. - Average grizzlymen productivity in secondary is 250 tons per shift while in primary it is only 25-30 tons, both at 343 mm (13 1/2 in. ) grizzly opening. - Powder consumption for secondary blasting increased from 8 grams per ton in secondary to 84 in primary. - The protection pillar between the under- cutting and the production levels was 60% broken in primary while 20% is usual for secondary. - Extraction advanced 5 cm per day in primary while a 50 cm per day rate is the aver- age in secondary. This is the main reason that after 8 years this primary block has a 20% extraction. Secondary blocks take 1.5 to 3 years to complete their extraction. - 80% of the boulders in primary rock are larger than 343 m (13 1/2 in.) with 10-20 % of them larger than 3 meters. -Direct cost of production (preparation, undercutting, extraction and haulage), using the traditional block-caving design for secondary rock, increased 3.5 to 4 times when used in primary rock. The following indicators of Table 1 show the rock characteristics differences.

Jan 1, 1981

This session was devoted to Surface Mining. Presiding was Virgil W. Carmichael, Vice President- Exploration, North American Coal Corporation, Bismarck, North Dakota, and John (Jack) F. Ratchye, Manager of Marketing and Resources, Peter Kiewit Sons' Co. Mining District, Sheridan, Wyoming. Subject-The new Federal Surface Mining Regulations-a thorough briefing as to content of law and how it will affect western mining. Introductory Speaker: William Hynan, Senior Vice President, National Coal Association, Washington, D.C. (See index for printed text of Mr. Hynan's paper.) Panel Members: The first speaker was George M. L. Robinson, Senior Hydrologist, Peabody Coal Company, Denver, Colorado. Mr. Robinson has a B.S. Degree from New Mexico University, Portales; Masters in Hydrology, Kent State, Ohio.

Jan 1, 1978

By A. Simkovich, C. W. McCoy

THE relationship among chromium, carbon, and temperature during the oxidation period of stainless steel melting was developed by Hilty et a1 1-3 whose studies were confined to plain chromium stainless steels. The simplified version of their relation is given by the equation:

Jan 1, 1962

By John D. Sullivan

The present article is one of a series which is being prepared by the Southwest Experiment Station of the United States Bureau of Mines in cooperation with the Department of Mining and Metallurgy, University of Arizona, Tucson, Ariz., of papers dealing with factors involved in the leaching of copper ores. A knowledge of the time required to dissolve the various copper minerals present in ores, as well as of the consumption of leaching reagents is very desirable, because with the decrease of the Nation's total tonnage of sulphide ores increasing attention is being given to the recovery of copper by leaching methods from low-grade disseminated ore containing both oxidized and sulphide minerals. As leaching has already been applied with success and profit, this study was undertaken to determine certain fundamental characteristics that are applicable to all ores suitable for leaching.

Jan 1, 1929

The classic description of Project Finance as "the reliance by lenders on the cashflow of a project, supported by the assets of the project with no recourse to the project sponsor's corporate balance sheet" has, like most other terms in the finance industry, evolved through recent usage. The area now under most scrutiny is the sharing of risks between parties either most able to take them or prepared to accept payment for them. Creativity in, and flexibility of financing structures have enabled project lending to continue under a dramatically different economic outlook. The diminishing competitiveness of the Australian producers in a global market place of uncertain commodity prices has discouraged the advancement of many large scale resource projects. The majority of new project financings has been designed to assist the relatively small company promote and develop its first projects. New trends- are emerging in four areas: sources of capital; borrowing structure; financing instruments (securitisation); and risk underpinning. As project financing becomes more widely used, the range of interested financiers grows. New initiatives contribute to its development and evolution with a view to increase effectiveness to the sponsor of any new venture.

Jan 1, 1987

By A. N. Winchell

Petrographic studies of over 1400 rock and mineral samples, and studies of their field relations, show that there is a complete gradation between sandstone and limestone; the lime-silicate rocks were produced by recrystallization of limestone; mineralization and silicification occurred after silication and at considerably lower temperature; carbonation occurred at still lower temperatures. IN CONNECTION with law suits between mining companies at Bingham, Utah, a few years ago, the writer made petrographic studies of more than 1400 rock and mineral samples in thin sections, and also careful studies of their field relations. In petrographic studies, even when an area is studied intensively, attention is commonly centered very largely on the unusual features of special interest, so that the relative abundance of rock types (or minerals or textures) can only be determined by a study of map areas outlined largely by field methods, and cannot be based directly on microscopic work. It is very uncommon, and usually impossible, to take samples at regular short intervals along and across formations. It is precisely because such methods were used at Bingham that the work presents a rare opportunity for determining, on a microscopic basis, the relative abundance of rock types and the continuity of gradations between rock types. At the same time, a study was made of the alteration of sediments under the influence of igneous intrusions, with results that are believed to be of interest and importance.

Jan 3, 1924

By John Starkey

"The development of the SAG Power Index (SPI) Test in Canada has created a new and accurate way to measure ore hardness in a SAG environment. Coupled with the standard Bond Ball Mill Work Index Test it is now possible to determine from these two relatively inexpensive laboratory tests, the amount of energy required to grind an ore from the primary crushed size to the desired liberation size. By testing multiple samples to discover where the hard and soft ore zones are located, the representative hardness distribution for the ore body can be determined and grinding equipment selected that is capable to meet production targets for all mining areas of the deposit.Previously, it was deemed prudent to select up to 50 t samples of ore for Semi Autogenous Grinding (SAG) pilot plant tests and a second 5 t sample for metallurgical pilot plant work. The methods outlined in this paper show how the 50 t sample is no longer required for SAG design because it is better to measure the representative hardness distribution of the ore body than the hardness of a “chosen” representative sample. This is demonstrated to be true by the fact that the lower horizons of an ore zone cannot initially be accessed to recover 150mm pieces, and the bulk samples taken, rarely represent the desired design hardness of the ore. Median hardness will not yield a good result in most cases and a clear understanding of the location and extent of the hardest zones is imperative to achieve a truly successful grinding circuit design.This paper discusses two plants (Kubaka and Agnico Eagle) that have been designed using SPI and Bond with no pilot plant test backup. Both have been very successful in that they can grind design tonnage on the hardest ores in the mine. This guarantees that the mine’s profitability is protected in any mining sequence. It also allows the extra power to be converted to higher throughput on softer ores if additional cash flow is needed. The advantages from the owner’s point of view are dramatic. This procedure will be attractive as well when considering the costs for test work, and the samples for testing. Existing diamond drill core is normally used and this allows the inclusion of data from the deepest regions of the mine. In addition, it is also clear that the decision to use a crusher can now be made at the design stage of a project based on measured parameters and the estimated capital costs of alternative designs."

Jan 1, 2003

By William F. Blake

The discovery of tin-ore in the Black Hills of Dakota dates from June, 1883, and short preliminary notices were published in September of that year.* The discovery-point is known as the Etta Mine, in the central portion of the Hills, about six miles east of

Jan 1, 1885