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By P. B. Demarsh

"Location: - On highway 59, 17 miles east of Val d 10r near junction of Montreal highway in Northwestern Quebec.Life; - Started production 1952, ceased 1965.Ore: - Pyrite, chalcopyrite and small amounts of free gold and goldsilver tellurides in narrow quartz-carbonate-tourmaline veins in granodiorite. Specific gravity 2, 70.Capacity: - 700 tons daily Bevcon ore supply, l 000 tons daily when custom ore available.Assay: - Heads 0 .140 oz. per ton; tails 0. 009 per ton; extraction 92.5%.Grind: - 75% minus 200 mesh at 700 tons; 68% minus 200 mesh at 1000 tons. Detention time 28 hours and 21 hours respectively.Treatment: - Cyanidation process.Reagents: - Per ton. Aero Cyanide (NaCn) 0, 50; crushed unslaked lime 1. 75; zinc 0. 03; litharge 0. 10; steel consumption 2. 25.Water: - Pumped from land-lock spring fed lake l 1/2 miles distant.Cost: - Per ton. Crushing 0. 13; grinding 0 .32; filtration 0. 07; cyanidation 0.14; miscellaneous 0.29; total 0.95.Power: - Hydro-electric, 25 cycle, 12, 000 volts reduced to 550 volts.Labour: - Predominantly French Canadian, nucleus English Canadians.Tailings: - Impounded low lying pond.Personnel: - 15 including supervision.Flow sheet: - Canadian Mining Manual l 9 5 6 .Building: - Wood truss construction: 3/ 4 in. siding, ten test and 1/ 4 in. transite outside. Corrugated galvanized iron roof. Ground level foundations. Internal self induced heating. Wood stave tank equipment."

Jan 1, 1966

By Emerson D. W

The search for economic mineral deposits is becoming more difficult as exploration goes deeper in the established mining camps and spread out to the surrounding covered areas, which may have an `overburden' some hundreds of metres thick. Geophysics is finding an ever increasing role in such exploration. When the target is zinc, the task often becomes even more difficult since sphalerite, the most commonly mined mineral, is non-magnetic, resistive, and relatively light compared to other sulphides. Fortunately, sphalerite commonly occurs in association with other sulphides, which are magnetic and/or conductive and/or heavy, thus most zinc-rich orebodies have at least one contrasting physical property to aid exploration. This paper presents the physical properties of sphalerite and other potentially important zinc minerals. Results of petrophysical measurements of samples from various zinc-rich ores are presented together with examples of geophysical surveys over a number of zinc deposits. The results show that the physical properties are not merely dependent upon the properties of the orebodies' constituent minerals. For example, the small (0.4 Mt) and low-grade (five per cent Zn + three per cent Pb + two per cent other sulphides) Flying Doctor deposit at Broken Hill, New South Wales (NSW) is much more conductive than the large (3+ Mt) and high grade (14 per cent Zn + five per cent Pb) Cadjebut deposit in Western Australia (WA). In the former case, tectonic stresses have

Jan 1, 1993

In the last few decades, a considerable amount of effort was directed at accurately determining the coal pillar strength to use for safely designing coal mines. The outcome of this early work was the well known Obert-Duvall, Holland-Gaddy, Bieniawski, and Salamon-Munro equations for coal pillar strength. All of these equations were developed for, and were calibrated with, pillars in a large room-and-pillar area such that the loading could be determined using the "tributary-area" theory. In order to account for the abutment loads associated with full-extraction mining, the empirical methods have typically adopted a simple conceptualization of the abutment load through use of an "abutment angle." Short of a complete numerical or analytical analysis of the coal seam and surrounding strata, very little work has been Fretted toward refining the empirical analysis of pillar loading. It appears that the vast majority of the research has been directed at determining the pillar strength, the numerator of the safety factor equation, when the denominator of the safety factor equation, the pillar loading, plays an equally important role in pillar design. This paper will address the deficit of pillar loading research by exploring the accuracy of the empirical abutment load calculations using insight provided by an elastic overburden model, a laminated overburden model and field observations. Ultimately, it is determined that a constant abutment angle probably over-predicts the abutment load as the mining depth increases.

By J. M. Keane

The Solution Mining review arrived too late to appear in the May issue. Solution mining, in its broadest definition, includes all forms of leaching where a lixiviant solution is brought into contact with a metalliferous or non-metallic ore and the resulting pregnant solution is processed for recovery of the valuable soluble material. Technologies such as dump leaching, heap leaching, stope washing and in situ lixiviant solution injection and recovery fit into this definition of solution mining. A publication entitled the US Gold Industry (Dobra and Thomas) reflects the major impact that solution mining techniques have had on precious metal recovery. In 1989 (the last year for which statistics are available), the United States passed Australia to become the third largest gold producing country in the world after South Africa and the Soviet Union. It is estimated that when the final figures are in for 1990, the US will probably pass the Soviet Union in gold output. If the state of Nevada is ranked as a separate country, it will rank fourth in the world in gold production for 1990. A good proportion of this increase in gold production over the past few years can be attributed to the application of solution mining technology to low-grade, precious-metal-bearing material. Solution mining techniques have also made inroads in copper production. Many operations located at former underground mine sites employ in situ leaching as an adjunct to conventional dump and heap leaching practices.

Jan 1, 1991

The following letter was received from Prof. Kemp in reply to a telegram expressing the greetings of the members attending the Annual Meeting in New York. "Melbourne Beach, Fla. Feb. 17, 1916. Dear Mr. Stoughton: The welcome telgram from the members of the Institute, which you kindly trans-mitted to me, came safely yesterday and I catch the next available mail with a heart-felt acknowledgment. I cannot express to you how greatly the remembrance cheers and braces me during the days of patient waiting for the feeling of over-strain to fully pass, and for the time when I can again be back among the friends in the Institute who are very clear to me. While I cannot reach all the members who joined in the telegram I will ask you to say to such as are available that I am profoundly sensible of the thoughtfulness which prompted the message. I write from a little bungalow on the ocean. side of the half mile or more of sand dunes, thickly grown with palmetto, which separate the ocean from the Indian River. Two miles or more of Indian River still intervene between the little colony of Melbourne Beach and Melbourne on the mainland and on the Florida East Coast R. R. where the telegraph station is. I was thus unable to respond at once by wire. Sincerely yours, (Signed) J. F. Kemp."

Jan 4, 1916

By M. G. Papasotiriou

For our company, S&B Industrial Minerals S.A., restoration of areas which were mined and the effort for bringing up again a balance of nature is an important priority over the last 3 decades. The successful qualitative results of restoration works have delivered to nature over 1.700.000 m2 of surface after mining activity. Our fundamental method in order to achieve the best results for restoration of mined areas is the use of local plants (bush or tree type). Grass and herbs are installed by using the method of hydroseeding. Small trees and bushes are produced and they grow up at our fully owned Milos nursery and they are installed during winter when weather conditions are suitable. During the initial stages of restoration activities a great amount of surfaces, adequately shaped, are delivered by the mining department covered with top soil. These surfaces are suitable not only for the local nature community but also for a combination between natural and agricultural environment. The above fact was a great chance to create small horizontal agricultural cultivations as pilots inside the restored areas. At the beginning the agricultural items that could potentially be installed in these pilot areas were studied and examined analytically. The following agricultural items were finally qualified to be furthermore researched: 1) Vineyard (Vitis vinifera ) 2) Prickly pear (Opuntia ficus indica) 3) Jojoba (Simmonsia chinensis) 4) Olive tree (Olea europea)

Jan 1, 2007

By Henry M. Howe

HENRY M. Howe, Bedford Hills, N. Y. (communication to the Secretary.) +-Mr. Johnson's explanation, that the rounding of the graphite masses in oxygen-bearing cast iron is clue to their being in part re-precipitated after re-solution in forming carbonic oxide temporarily with that oxygen, is certainly most attractive and suggestive. It remains to be shown whether this rounding occurs also when 'the solidiification is too rapid to permit this process to goon. J. E. Johnson Might easily test this by casting a single ladleful of his oxygenated iron in masses of varying size. If' this present hypothesis is true, then the rounding ought to increase progressively with the size of the casting, and with the distance from the outside, that is to say with the time available for re-solution and re-precipitation. I question whether a like benefit is to be expected even on this hypothesis, from the oxygenation of steel. The spheroidizing of graphite does good because graphite itself is so weak. But the constituent which can be spheroidized in steel is its cementite, which is a source of strength. Lamellar pearlite, in which this cementite in effect forms long dendrites, is far stronger than divorced pearlite, in which these dendrites have been broken up into spheroids. Even the surfaces of contact between ferrite and cementite are probably sources of strength because of the amorphous iron which probably fills them.

Jan 1, 1917

By Bruno Sceresini

Prospectors and small scale mmmg companies have long expressed the wish for a highly mobile mineral processing plant. This is especially so in the case of gold mining as relatively small deposits can be highly profitable due to the relative ease of producing a marketable product when compared with the refming and marketing costs incurred with base metals. This paper will concentrate on gold ore treatment in fitting with the theme of the 1996 Randol Gold Forum but the principles may also be applied to base metal ores. The development and application of the Atomaer Filblast Gas Shear Reactor as a cyanidation tool has removed the con­straints of plant size in pulp cyanidation applications. KC Dodd and Associates, Consulting Engineers and Australian Mining Advisers, Pty Ltd, have designed a 1,000,000 and a 250,000 tpa fully modularised ore treatment plant. Various module configu­rations can be arranged to treat a wide variety of ores ranging from simple gold ores to gold-copper and base metal ores. This paper will limit the discussion to comparing the capital and operating costs of a conventional and a modularised 1 million tpa gold treatment employing a number ofnovel concepts which complement the compact, high capacity Filblast Cyanidation Process and the AARL pump Cell Adsorbers. The design described in the paper not only reduces equip­ment sizes and allows for rapid deployment of a sizeable capac­ity plant but also offers significant capital and operating cost benefits.

Jan 1, 1996

By J. J. Rutledge, C. A. Herbert

In 1916 the Bureau of Mines, the Illinois Geological Survey, and the University of Illinois, working under a cooperative agreement, began an investigation of the subsidence of the surface above coal- mining operations. Four widely separated places where mining was in progress were selected as observation stations-one in the northern Illinois longwall coal field, one in the central Illinois coal field where the room-and- pillar panel system of mining was being used, and two in the thick coal of southern Illinois where the room-and-pillar panel system of mining was employed. These four points of mining activity gave a rather wide opportunity for observing subsidence when different mining methods were used. The four places selected for investigation of surface subsidence due to coal mining have been designated as follows: 1. A, in the northern Illinois longwall coal field, where the coal company has been operating coal mines for 30 years and where long- wall advancing is the only method of mining. 2. B, in Perry County, where panel room-and-pillar mining of a thick seam of coal is in progress and where mining operations have been carried on about 40 years. 3. C, in Macoupin County, where the coal company has been min- ing coal by the panel room-and-pillar method for about 15 years. 4. D, in Franklin County, where the coal company has been mining coal for 10 years by the panel room-and-pillar method.

Jan 1, 1927

By Kimberly Martin

The EFFC/DFI Carbon Calculator provides the deep foundations industry the opportunity to be a leader when it comes to carbon reduction. This tool was created 10 years ago in an extensive effort by the European Federation of Foundation Contractors (EFFC), DFI, member organizations and Carbone 4, a consultant with ex- perience in life cycle assessment. The tool was born out of the fact that governments and clients were asking for embodied carbon information for foundation systems, and that in- dividual companies were building their own calculators to meet these requests. To help all member organ- izations achieve compliance, and to have a sector-specific tool that is certified to the prevailing standards, EFFC and DFI agreed to partner to create the carbon calculator, which is: Excel based and, therefore, easy to learn and use Updated on a regular schedule Certified to ISO 14067, GHG Protocol and PAS 2050 Free and available for anyone to use Even though this tool is free and easy to use, most projects in the industry do not have a carbon calculation performed. The case to use the calculator is more obvious for members in places like Europe where there are stricter reporting standards and government work can be driven by sustainability over cost. In North America this is not the case, yet. Without directives from clients and governments, what can compel the industry to start regularly using this tool and care about the carbon emissions of projects during design and construction?

Nov 1, 2022

By H. W. Hughes

"The Wasamac Gold Mines mill, situated 10 miles from Rouyn-Noranda on highway 59, commenced milling April 1st 1965 at a rate of 700 tons per day. This has gradually increased to over 1200 tons per day in December. The mill has done up to 1400 tons on occasion.The ore was formed in the Wasa shear zone by means of replacement. The minerals which replaced the original rocks were carbonates, quartz, pyrite, chlorite, gold and silver. Work index varies from 9. 6 on the chlorite to 11. 6 on the quartz. The gold is very finely disseminated throughout the gangue and while associated with the pyrite is not included in the pyrite. Very seldom is gold found or seen in the free state.Test work showed a medium fine grind of 85 to 90 per cent was necessary to achieve a 95.00 per cent extraction. Straight cyanidation time of 30 to 36 hours was indicated. This has been borne out by subsequent mill performance with a grind around 87 per cent minus 200 mesh and extraction ranging from 95 to 96 per cent.When it was decided to bring the Wasamac property into production, the Bicroft Uranium Mines Ltd. crushing and grinding units together with one pebble mill and the pachuca tanks from Dyno Uranium Mines Ltd. were purchased.Wasamac crusher house and mill buildings are of laminated wood construction, covered with 5/ 8th inch plywood and corrugated iron sheeting."

Jan 1, 1966

By K. Rajani Kanth

Environmental problem is the major concern for any industry and there is a great need to that along green lines. Sangam Dairy being one of the most famous and wide spread Dairies in India, produces wide spectrum of milk products. The BOD levels of effluent water of this industry with MIF treatment were found to be around 100 ppm. Lot of research has been expended in the past to bring down the BOD levels to bare minimum. The main objective of the present study is to minimize the BOD level to the required level stipulated by environmental standards by employing various seeding materials. For this purpose microbes like Bacillus Subtiles, Pseudomonas, Aspergillas, Staphylococcus, and Pencilium have been employed and BOD levels were analyzed. Various Reagents, solutions with different dilution levels have been successfully prepared. Initial and final Dissolved Oxygen levels were determined before and after incubation. From the DO data, BOD was evaluated for all samples and comparison analysis of various seeding material was carried to suggest the efficient seeding material for the ETP plant. In the process, solutions of different dilutions have been prepared using difficult reagents. These samples are treated with above mentioned microbes and BOD levels are estimated. It has been observed that staphylococcus and Pseudomonas proved to be the best seeding materials. When there microbes have employed BOD levels fall to less than 10 and 20 ppm respectively

Jan 1, 2006

By Scott G. Britton

Thin-seam mining presents unique challenges when management or economic conditions require significant productivity increases. These challenges can be further amplified depending on such factors as labor unions, federal and state regulations and market characteristics. This article explores the turnaround situation occurring at Tanoma Mining Co. (TMC), a medium-sized, underground coal mining company in central Pennsylvania. The company has used a systematic approach of improving management controls and direction, labor relations and communications to improve its cash flow from negative to positive within a projected five-year span. An intensive upgrade-rebuild-replacement program for mining equipment and systems has also been established to support other management activities. Discussion Thin-seam coal mining is an industry within the broader industry of coal mining. Thin seam mining faces the same cost pressures and engineering problems as its higher-seam competitors, without the advantages of moving volume per foot of extracted material. To stay at economic parity with others requires additional creativity within the management team to extract higher productivity gains from the existing workforce and mining systems. The Tanoma operation is a deep mine in Indiana County, PA, about one hour northeast of Pittsburgh. Coal is extracted from the Lower Kittanning "B" seam. It lies about 91 m (300 ft) below the surface and averages 0.9 m (I ft) in height. Continuous mining units using mobile bridge conveyors or shuttle cars

Jan 1, 1991

By J H. Kyle

Cyanide is a significant cost in gold processing, as well as an environmentally sensitive issue. It has been suggested that precipitation of cyanide from leach liquors as copper-iron-cyanide compounds such as Cu2Fe(CN)6 may account for part of the total cyanide consumption. This may be especially true for ores that are rich in both copper and iron minerals. Ammonia addition has been shown to decrease the cyanide consumption by copper. Cu2Fe(CN)6.xNH3 precipitates have also been postulated to form during conventional cyanide detoxification processes, using oxidants such as SO2/air, with ammonia arising as a breakdown product from the oxidation of free cyanide. The present work has examined the conditions under which such precipitates may form, particularly in gold plant process and detoxification liquors. Ammonia and pH were found to have a large effect on the extent of precipitation. The compounds that were formed were found to comprise mainly Cu2Fe(CN)6.7H2O, as well as a range of NH3-bearing variants. The stabilities of the various precipitates are important from an environmental perspective. The long-term stability of copper ferrocyanide precipitates in tailings dams may be a problem under alkaline conditions and when some free cyanide is present, elevating the measured total cyanide in solution significantly. Case studies including data from actual plants are also considered, and the importance of these effects is reaffirmed from these results.

Jan 1, 2000

From L. K. Armstrong, Secretary of the Columbia Section of the Institute, we have received information as to the activities and plan of the Spokane Engineering and Technical Association, which was recently organized under the joint auspices of the local sections of the American Institute of Electrical Engineers, the American Society of Civil Engineers, and our own Institute. The first meeting was held on September 20, at which a program for the following year was adopted. The, meeting was then conducted by the Civil Engineers., the principal business being the reading of a report by Mr. Flinn, Secretary of the United Engineering Society. The second meeting was held on October 18, of which the Columbia, Section of our Institute took charge. According to the program adopted, meetings will be held regularly on the third Friday of each month, except June, July and August. It is understood that these meetings shall not interfere with nor abridge the independent activity of the participating societies. The proposed work of the Association is to be conducted by a large number of committees, whose attention will be devoted to such subjects as the following: Municipal, Highways, Resources, Manufacture and Industries, Legislative, Educational, National and State, Patents and Inventions, Americanization, Safety and Rehabilitation, Research, Emergency. When all of these committees shall have been filled, and their work begun, it is expected that the engineers of Spokane and vicinity may take a more active part in things affecting human welfare in that vicinity.

Jan 11, 1918

In recent years, with the advent of new steelmaking procedures, the emphasis has turned away from conventional teeming and has been directed toward continuous casting. This paper points out the fact that there are still new methods being considered to decrease the problems and costs associated with conventional teeming. Although Inland has had no experience with the repair of mold lugs, we do find some problem with damaged ears associated with mechanically capped steel. When pouring bottle tops, any crane movement or leak from the pouring nozzle may result in steel over the top of the mold which, in turn, may result in the shearing of the mold lugs during stripping. Recent back pouring practices increase the chances of this occurring. At Inland's steelmaking shops, we have tried to combat this problem by various methods such as burning the steel from around the top of the mold at the pouring stand with oxy-gas torches. Last year, No. 4 BOF began a conversion from round to elliptically shaped bottle top caps. This change has greatly reduced the chance of splashing due to crane swing by increasing the dimension in the direction on normal swing. The answer to this particular problem is, however, tighter control of pouring performance. We are presently engaged in a process of re-education of personnel and experimentation with different materials and designs of nozzles, heads, and sleeves to help us achieve our goal.

Jan 1, 1972

Henry M. Parks, director of the Oregon. Bureau of Mines and Geology, has supplied the following information regarding a recent discovery .of manganese ore in Jefferson County, Oregon, about seventeen miles southeast of the railroad at Eagle Point, a station on the P. & E. Railway. The occurrence is about five miles southeast of Lake Creek Post Office and near the confluence of Lost Creek with the south fork of Little Butte Creek. The manganese ore occurs as psilomelane and pyrolusite, disseminated through a flat bed of volcanic tuff breccia; at a point where the bed was penetrated by a churn drill hole, the thickness of the ore-bearing stratum was 30 ft. Development thus far has consisted of open-cuts, one of which exposes a face about 40 ft. high and 75 ft. broad. Other smaller open-cuts have followed the bed for a. distance of 400 yards. The nodules of manganese mineral vary from a maximum of 25 to 50, lb. down to the size of beans and others as small as mustard seed. These grains, when clean, average from 55 to 58 per cent. manganese. A 12-ft. groove sample in the face of the main open-cut yielded 14.86 per cent. manganese. The peculiar occurrence of the manganese nodules should present but slight difficulty in concentration. A small experimental mill was built last winter, comprising gyratory crusher, rolls, and jigs, which,

Jan 8, 1918

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

By David Sinclair, Philip B. Bucky

THE dimensions and shapes of mine structures may at present be determined by (1) field experience, (2) structural calculations, and (3) barodynamic tests.§ None of these, however, provide information as to the stresses, their direction and distribution in a mine structure. For the design of pillars, the placing of openings relative to working places such as gangways, haulage levels, etc., this information is desirable. Photoelastic methods provide this and, while relatively new, their application in all engineering fields is assuming increasing importance. This paper, therefore, will present the method with a few applications to mining, and with sufficient reference for further study by the reader. PART I THE PHOTOELASTIC METHOD The photoelastic method of stress measurement determines the stress distribution in a two-dimensional model by optical means. It makes use of the fact that when a piece of isotropic transparent material, such as glass, celluloid, or Bakelite, is stressed and viewed in polarized** light a picture is seen which indicates by its color bands of light, or fringes, the magnitude of the stresses, their direction and their distribution. GENERAL EXPLANATION The stress at any point 0 in a structure (Fig. 1), may be resolved into two components, P and Q, each a pure tension or compression, at right angles to each other, called principal stresses.1 To fully identify the stress, the values of P and Q and their directions or angle [0] must be known.

Jan 1, 1940

February 18th, 1873. THE Institute assembled in the Hall of the Boston Natural History Society on Tuesday evening. Dr. T. Sterry Hunt, of the Boston Institute of Technology, after a brief address of welcome to the Institute, read an introductory paper on the Geognostical History of the Metals. President Raymond responded to the welcome of Dr. Hunt. The following names were then presented to the Institute, with the recommendation of the Council, for election Adams, J. M., - Silver City, Idaho. Daggett, Ellsworth, - Salt Lake City, Utah. Geist, Alfred W., - Boston, Mass. Hays, Dr. S. Dana, - Boston, Mass. Heinrich, Oswald J., - Midlothian, Va. Johnson, J., - Braidwood, Ill. Leckie, Robert G., - Actonvale, Canada. Lyman, Edward, - Troy, N. Y. Maltby, William, - Braidwood, Ill. Nichols, Lyman, Jr., - Boston, Mass. Ordway, Prof. J. M., - Boston, Mass. Rand, Theodore D., - Philadelphia, Pa. Richards, Prof. Robert H., - Boston, Mass. Rockwell, Prof. Alfred P., - Boston, Mass. Roepper, Charles W., - Bethlehem, Pa. Schulz, A. von, - Central City, Colorado. Singer, William F., - Pittsburgh, Pa. Spillsbury, E. G., - New York. Wells, Calvin, - Pittsburgh, Pa. The session concluded with the reading and discussion of a paper, by Henry Engelmann, On the Mines and Ores of the Little Cottonwood Canyon, Utah. The second session was held on Wednesday morning, when the following papers were presented; On the Midlothian Coal Mines, by Oswald J. Heinrich. On the Probable Existence of Microscopic Diamonds in California, by Prof. Benjamin Silliman.

Jan 1, 1873