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By A. A. Beard

ABOUT three years ago, I. L. Dunn, of Marietta, Ohio, found that wells could be cleaned by blowing with compressed air; this method has been used with great success on many wells in the Marietta, Ohio, district, where compressed air is being used to increase production, by forcing oil through the depleted sands. About a year ago, the process was successfully used to clean out wells in the Lenapah pool in Oklahoma, where an air plant had been installed, under the supervision of I. L. Dunn. Wells from 900 to 1000 ft. deep, with 40 ft. of sand and cavings in them, were cleaned out in from two to three days. The use of this process had, so far, been limited to properties using the Smith-Dunn process, where compressed air, under suitable pressure and volume, was available. For other properties, a portable compressor seemed essential; this was built and successfully demonstrated by Mr. Dunn, for the Tidal Oil Co. in September, 1924. The process of cleaning out with air has been described.1 It consists of lowering the tubing into the well, with a shoe or nipple of heavy pipe substituted for the perforated anchor on the bottom. Into the tubing, compressed air is introduced through a rotary swivel hose at the top, or by means of swing connections. The tubing is lowered to the top of the cave to be cleaned out, several barrels of water are put into the hole, and the compressed air is turned on. This blows out the material between the casing and the tubing, the tubing being lowered as the material is removed.

Jan 9, 1925

By W. M. Bertholf

IN 1945 tests were made in the coal washery of the Colorado Fuel and Iron Corporation, at Pueblo, Colo., to determine the value of the Humphreys spiral. So far we have demonstrated that it is of definite value to us in rewashing a portion of our table middlings; and we are fairly certain that this is not necessarily the only place in which it can be used to advantage. Because of manpower and material shortages, experimental work has been discontinued for the present. Three of the spirals are being installed for use in rewashing the middlings, and testing and experimental work will proceed when this installation is completed. All evidence secured so far points to the fact that the spiral can make an effective separation of heavy material below 8-mesh; but that it is ineffective in removing larger, heavy material. This, of course, will limit its use to fine coal or a classified feed containing no heavy material larger than 8-mesh. In considering the results of our tests, it should be noted that the feed was our table middling, and that any real separation of this material is a "moral victory," as there is little material that could be properly called coal and practically no heavy rock, the consequence being that previous attempts to clean the middlings have not been at all successful. Several articles dealing with the spiral and its use in treating heavy minerals have already been published,1 but for the benefit of those who have not seen these we include a brief description of the spiral and of the way it operates, taken from Bulletin 4 of The Humphreys Investment Co.: The Humphreys Spiral Concentrator consists of a spiral conduit of modified semicircular cross section. Ore pulp is fed to the top and, as it flows downward, the heavier particles concentrate in a band along the inner side of the pulp stream (Fig. I). Outlets for removal of products are located at the lowest points in the cross section of the conduit. Wash water, added at the inner edge of the stream, flows outwardly across the concentrate band. The width of concentrate band removed at the outlets is controlled by adjustable splitters. Concentrate is usually removed from the upper portion of the spiral and middling from the lower portion. Tailing is discharged from the lower end. Tests are usually made in closed circuit, since this provides a maximum of information with a minimum amount of sample. Fig. 2 shows the spiral set up for closed-circuit testing, and gives a good idea of the general arrangement of such an installation. The small cyclone separator is used to provide clean wash water without introducing additional water into the circuit.

Jan 1, 1946

"Since all gold mills must sooner or later be cleaned up for permanent shutdown it was felt that a record of what was done at one mill might be of some help to those who will have to do the same job in the future,In cleaning up the mill of Delnite Mines Limited, I had an advantage that most mill superintendents will not have in that I started up the mill and was there until it was shut down, It was also known for two years approximately when the shutdown would be and for a year almost the exact time. This, of course, made careful planning possible and enabled me to get advance information that wouldn't have been available had the shutdown come unexpectedly,Early in 1964 calculation of ore reserves and the known number of working places available indicated that the mine would run out of ore sometime in August or September but not later than October, The time of course would vary with the number of competent miners that could be retained until the shutdown. Since the mining method used exclusively on the ore then remaining was cut and fill, it was known that once mining operations ceased it would require at most two days to crush and grind the last of the ore.In March 1 964 I took samples of the concrete floor under the precipitation presses, in the flux room and furnace room of the refinery and from the assays obtained proved that there would be no profit in breaking up the concrete to recover the gold from it, Samples taken from the top half inch of the concrete floors assayed less than 0, 10 oz per ton,"

Jan 1, 1966

By M. R. Geer

THE increase in the number of coal-cleaning plants employing dense-medium processes occurring since 1946 is especially interesting when viewed historically. Both sand and magnetite were introduced as material for heavy mediums at about the same time, sand in the Chance process in 1921 and magnetite in the Conklin process in 1922, but from that point on their records diverge. The Chance process enjoyed a steady growth from its inception, whereas no additional magnetite plants were built in the United States for over 20 years. Then, following the close of the World War 11, magnetite was again introduced, this time with marked success. During the following years some 47 plants employing magnetite medium were built.

Jan 7, 1953

By J. R. Campbell

THE need for standardizing methods of arriving at definite conclusions regarding the cleanability of a given coal, and for measuring the performance of coal-cleaning equipment, is constantly increasing. Earlier notes by the author on this subject are amplified in this paper, because he believes that better preparation of bituminous coal is a partial solution of the coal operators' troubles. WASHABILITY STUDIES The term "washability" of coal was coined when washing was the universal method of separating coal from its impurities by utilizing their difference in specific gravity. This and analogous terms are still used in their broad sense although pneumatic or air separation is now used to clean coal. These terms are so used in this paper. Too much time or money, can hardly be spent on "feed surveys" to get a "picture" of the coal that is to be cleaned. There have been too many "rule of thumb" methods used. Screen analyses and "sink-and-float" tests on the raw coal enable the coal operator and washery man to predict within reasonable limits the results that may be expected from any efficient cleaning apparatus.

Jan 1, 1928

By Raymond O. Ladoo

FUSED quartz is a glass made by the fusion of nearly pure silica. Some confusion in terminology exists but in the trade today "fused quartz" generally refers to the perfectly transparent colorless product made from rock crystal whereas "fused silica" is a white, translucent product made from silica sand. Vitrified silica is the term preferred by purists for all quartz glass, but it lacks the definiteness of -the trade terms. Since the raw materials, methods of production, and properties of the finished products arc different for the two types, the trade terms are preferred. As fused quartz is amorphous, it-physical properties differ greatly from those of quartz crystal. Lacking crystallographic directions and having no piezo-electric properties, fused quartz. of course, has no value for the making of radio oscillator plates; but it does have other valuable and unique properties. Perhaps the 'best known and most useful properties are its extremely low coefficient of expansion and its ability to transmit short-wave ultraviolet radiant energy. Crystal quartz not only has an aver-

Jan 1, 1947

By Donald J. Reining

The California Surface Mining and Reclamation Act (SMARA) is the nation's first legislation establishing a statewide mineral resource policy governing mining activities that recognizes regional needs and retains local autonomy. The Southern California Rock Products Association supported this proposed legislation. It was through our efforts that SMARA was passed in 1975. The local planning and zoning processes, which are so critical to the mining industry, have been significantly improved with implementation of SMARA. Recognition of the importance of the mining industry is now being developed by the State Mining and Geology Board and the California Division of Mines and Geology (CDMG).

Jan 1, 1984

By John A. Brooks

The description of a phosphate flotation operation is repeat information for many people, except for variations in flow sheets. This paper is written to show the variations in flows, and to give enough. of the overall flows to allow anyone not familiar with the operation to be able to formulate a fair idea of the operations.

Jan 1, 1962

By J. C. May, G. M. Elliott, J. J. Brady

Increased clearance was required in two railroad tunnels that were built about the time of the Civil War. Clearance infringements, whether they be excavation tights or caused by ice accumulation, reduce tunnel serviceability. Achieving increased clearance often means disturbing the ground and old ground support structures. Access and transportation needs dictate how and when the work can be carried out, and strongly influence the design approach and the methods used by the contractor to execute the work. This paper explores the pertinent considerations of the owner, the designer, the field inspection team, and the contractor in bringing this project to a successful conclusion.

Jan 1, 1997

By Andrew Cecala

Miner?s exposure to dust remains a top concern among regulatory agencies, particularly at production facilities with high levels of silica. This respirable dust is present in almost all operations and is a direct cause of the deadly disease silicosis. Silica is one of the most abundant minerals on Earth and is a threat at all operations, especial-ly granite and sand and gravel facilities. The National Institute for Occupational Safety and Health continues to analyze silica?s threat. The institute?s research indicates that heavy-equipment operators have an increased risk to dust exposure, especially when drilling or breaking rock, even when working from an enclosed cab. However, there are methods to reduce an operator?s exposure further, according to recent NIOSH research, which is detailed in its report, Improving Air Quality in Enclosed Caps with Uni-Directional Filtration/ Pressurization System. NIOSH indicates that when surface mining equipment is new, the operator?s dust exposure is normally at accept-able levels. As the equipment ages and components such as gaskets and seals deteriorate, the level of protection can degrade to a point where it is no longer acceptable. However, the institute indicates that at least two critical factors necessary for an effective system.

Jan 1, 2009

The notion prevails that writing is a knack, that the skilful use of the pen is a gift of nature. This is an error. Dogberry may be responsible for it; he said: "To be a well-informed man is the gift of fortune, but to write and read comes by nature". Because Dogberry said it, we may be sure that Shakespeare thought otherwise. Ability of any sort may be partly innate, but my own observation and experience lead me to conclude that most of the easy writers have become so by constant practice. As I recall the names of men successful with the pen, I remember that most of them have written a great deal and have taken particular pains to improve their style. The suggestion that proficiency in the difficult art is a happy accident provokes a sardonic smile. The larger part of the great writing in our literature is the result of persistent effort. An easy fluency has been the undoing of many; their flamboyant and fantastic scribbling has proved as perishable as froth. This criticism applies to technical writing also; in order that a technical description or discussion may hold the interest of the reader, at least long enough to cause him to read it to the end, the writing must be done carefully and systematically; otherwise it will fail in its purpose of conveying information. Clearness is absolutely essential. "It is not enough to use language that may be understood; it is necessary to use language that must be understood."* The purpose of writing, at least of that which is meant to be read by others, is not only to express ideas but to communicate them. Lack of perspicuity may prove as bad as

Jan 1, 1931

By T. A. Rickard

The notion prevails that writing is a knack, that the skilful use of the pen is a gift of nature. This is an error. Dogberry may be responsible for it; he said: "To be a well-informed man is the gift of fortune, but to write and read comes by nature". Because Dogberry said it, we may be sure that Shakespeare thought otherwise. Ability of any sort may be partly innate, but my own observation and experience lead me to conclude that most of the easy writers have become so by constant practice. As I recall the names of men successful with the pen, I remember that most of them have written a great deal and have taken particular pains to improve their style. The suggestion that proficiency in the difficult art is a happy accident provokes a sardonic smile. The larger part of the great writing in our literature is the result of persistent effort. An easy fluency has been the undoing of many; their flamboyant and fantastic scribbling has proved as perishable as froth. This criticism applies to technical writing also; in order that a technical description or discussion may hold the interest of the reader, at least long enough to cause him to read it to the end, the writing must be done carefully and systematically; otherwise it will fail in its purpose of conveying information. Clearness is absolutely essential. "It is not enough to use language that may be understood; it is necessary to use language that must be understood."* The purpose of writing, at least of that which is meant to be read by others, is not only to express ideas but to communicate them. Lack of perspicuity may prove as %ad as

Jan 1, 1931

By M Hawkins

The Clem Jones Tunnel (formally known as the North-South Bypass Tunnel), a A$2.88 billion road tunnel project in Brisbane, Queensland, was successfully completed almost seven months ahead of schedule. The project included two parallel 4.7 km long road tunnels, 740 m of intermediate roadway access ramps and two auxiliary ventilation tunnels. The tunnels incorporate intelligent tunnel systems, best practice fire and life safety standards and typical civil tunnel elements.Over the duration of the project the Parsons Brinckerhoff (PB) and AECOM (formally Maunsell) design joint venture (MPB) were Lead Designers to the Leighton Contractors and Baulderstone Bilfinger Berger Joint Venture (LBBJV). Construction of the toll road commenced in September 2006 and was completed in March 2010, with the tunnel opening then. Contributing to the success of this project was the continued support the lead designers gave throughout the construction period.This paper will focus on some of the structural elements that contributed to the success of the project – in particular the cable tunnel structure, a small precast, culvert shaped element under the pavement of the mainline tunnel, and the fit-out of the Gibbon Street shaft which were designed to be constructed in a combination of precast and in situ concrete.The cable tunnel was incorporated early in the design phase and runs the length of much of the tunnel. This paper will outline the challenges faced by the designers with implementing this system which provided significant construction advantages, among which were being able to install a separate ventilation duct during construction and to start fitting out the mechanical and electrical conduits and drainage system while tunnelling was still underway.The Gibbon Street shaft had a length and width of 20 m by 40 m and an overall depth of 38 m. A 20 m high structure of precast and in situ concrete was constructed in the base to accommodate mechanical and electrical equipment and provide a take-off access for the southern ventilation tunnel. The construction purpose for this structure was to provide a junction between the tunnel boring machine (TBM) and the roadheader-style tunnels, a staging platform for commencing the roadheader tunnelling, and a platform where the TBMs could be dismantled and removed.The design was assessed and reviewed many times throughout the construction process to address the needs of each of these stages. Innovative use of precast concrete was used to minimise construction time.Additionally, the designers provided support to the construction team from the time of design completion through to the tunnel opening. This meant that the changes to the design and adjustment of construction loadings could also be assessed. The fi nal outcome resulted in an efficient construction sequence and a project that has provided an excellent outcome for the client, stakeholders and community.

Mar 8, 2011

By Armstrong M

The Clermont Coal Mine will export steaming coal from the Wolfang Basin in Central Queensland, Australia. It is expected to be developed in the mid-1990s.The majority of the reserves lie in the 30 m thick Wolfang Seam. Overburden depth varies from 80 m at the subcrop line to 190 m in the centre of the basin.

Jan 1, 1992

By F. Chavan

1. Introduction The new Cleuson-Dixence development project in the Valais region of the Swiss Alps, involves the construction of a new link between the Grande-Dixence dam (still world recordholder with a height of 300 m) and a power house on the banks of the Rhone consisting of approximately 20 km tunnels and shafts, and involving a fall of about 1900 m. This 1200 MW project will replace an existing 900 MW structure built in the 1960s, no longer considered efficient. The new project comprises a head race drift about 15.8 km long, a surge tank, an inclined cascade shaft 4,2 km long, and an underground power station. The work for lots C and D (head race drift from Tortin to Tracouet, surge tank, six adits ans the complete inclined shaft) was awarded to our group (Prader, Locher, SELL, Losinger, Evéquoz, Dénériaz, Imboden and Bouygues). The geological conditions are: Lower part of the shaft (300 m) : sedimentary - sandstone and soft tertiary sandstone. Middle and upper part (2600 m) : metamorphic - upper and lower carboniferous, interrupted by triasic chipping. The horizontal section (7 km) consists of mica

Jan 1, 1995

By Ray Mason, Damien Label, Howard Bernier, Kevin McDermott, Kevin Coombs

"GeneralWabush Mines is an unincorporated joint venture of seven steel companies and Pickands Mather & Co. The mining and concentrating facilities are located in southwestern Labrador and the pelletizing and shiploading facilities are at Pointe Noire, 200 miles south, near the town of Sept-lies.The operation is based on a 5 ½ sq. mi. specular hematite deposit with a reserve of 375 million tons of concentrate. Annual production capacity is rated at 6 million tons of pellets per year. The final upgrading process utilizes high-tension separation of silica following wet autogenous grinding, spiral gravity separation and fluo-solids drying. The concentrate is railed in closed cars to Pointe Noire. The concentrate is reground dry and pelletized on Dravo Lurgi travelling grate machines to produce an oxide pellet with 65.5% Fe, 3.0% Si02, 1.95% Mn and 93.5% Tumble Index.HistoryPlant operations commenced in 1965 with a concentrator capacity of 5.3 million tons per year and a pelletizing capacity of 4.8 million tons per year. The original facilities for classifying the crude ore into fine and coarse fractions for storage purposes before reblending as autogenous mill feed were found to be unnecessary and were by-passed after plant startup. Capacity of the operation was increased to 6.0 million tons of pellets per year in 1968. This increased capacity required the installation of an additional160 cleaner spirals in the ore dressing plant, a new 5000 hp ball mill, three balling circuits and increased cooling air capacity in the pellet plant.In 1970, the regrind circuit in the pellet plant was converted to dry grinding and a significant reduction in grinding media consumption and maintenance costs was realized. A ninth grinding mill of 5000 hp capacity was installed to compensate for the reduced capacity in going from wet to dry grinding."

Jan 1, 2000

THE sessions of the Institute were opened on Tuesday evening, October 26th, at Garrett's Hall, by Mr. Charles A. Otis, Chairman of the Local Committee of Arrangements, who welcomed the Institute to Cleveland, and introduced Col. Charles Whittlesey, who ad¬dressed the Institute briefly on the coal deposits of Ohio. Col. Whittlesey described the situation and character of the coal-beds of the State, and gave a short history of the use of raw coal in the manufacture of pig-iron, and spoke of the excellent quality of metal produced. The aid that a body of scientific miners and metal¬lurgists were capable of giving in the development of coal and other mineral resources was dwelt upon, and the hope expressed that the visit of the Institute to Cleveland might be profitable as, well to its members as to the citizens of the State. The President, Mr. A. L. Holley, responded to the welcome of Mr. Otis and of Col. Whittlesey, and read an introductory address on Some Pressing Needs in the Iron and Steel Manufacture. The following members and associates, duly proposed and indorsed by the Council, were then elected MEMBERS. Alfred S. Bertolet, - Youngstown, Ohio. Henry Binnse, - Chicago, Ill. John Birkinbine, - Philadelphia. Andrew A. Blair, - Watertown Arsenal, Mass. Ogden Bolton, - Canton, Ohio. Lloyd Booth, - Youngstown, Ohio. E. Borda, - Philadelphia. N. P. Bowler, - Cleveland, Ohio. Alexander E. Brown, - Cleveland, Ohio. C. F. Brush, - Cleveland, Ohio. S. M. Carpenter, - Cleveland, Ohio. James Cartwright, - Youngstown, Ohio. Henry Chisbolm, - Cleveland, Ohio. Wilson B. Chisbolm, - Newburgh, Ohio. W. H. Clarke, - Millertown, Pa. James E. Clayton, - Ore Knob, N. C.

Jan 1, 1876

The sessions of the Institute were opened on Tuesday evening, October 26th, at Garrett's Hall, by Mr. Charles A. Otis, Chairman of the Local Committee of Arrangements, who welcomed the Institute to Cleveland, and introduced Col. Charles Whittlesey, who addressed the Institute briefly on the coal deposits of Ohio. Col. Whittlesey described the situation and character of the coalbeds of the State, and gave a short history of the use of raw coal in the manufacture of pig-iron, and spoke of the excellent quality of metal produced. The aid that a body of scientific miners and metallurgists were capable of giving in the development of coal and other mineral resources was dwelt upon, and the hope expressed that the visit of the Institute to Cleveland might be profitable as well to its members as to the citizens of the State. The President, Mr. A. L. Holley, responded to the welcome of Mr. Otis and of Col. Whittlesey, and read an introductory address on Some Pressing Needs in the Iron and Steel Manufacture. The following members and associates, duly proposed and indorsed by the Council, were then elected MEMBERS. Alfred S. Bertolet,.. .. . Youngstown, Ohio. Henry Binnse,. Chicago, Ill. John Birkinbine,.. .. . Philadelphia. Andrew A. Blair,. .. .. Watertown Arsenal, Mass. Ogden Bolton,. .. .. Canton, Ohio. Lloyd Booth,..Youngstown, Ohio. E. Borda,..Philadelphia. N. P. Bowler,.. .. . Cleveland, Ohio. Alexander E. Brown,.... Cleveland, Ohio. C. F. Brush,.. .. .Cleveland, Ohio. S. M. Carpenter,.. .. . Cleveland, Ohio. James Cartwright,.. .. . Youngstown, Ohio. Henry Chisholm,.. .. . Cleveland, Ohio. Wilson B. Chisholm,.. .. . Newburgh, Ohio. W. H. Clarke,.. .. . Millertown, Pa. James E. Clayton,. .. .. Ore Knob, N..C.

Jan 1, 1913

By AIME AIME

OUR own Institute of Metals and Iron and Steel divisions cooperated with the Iron and Steel Division of the American Society of Mechanical Engineers, the American Welding Society, and the American Society for Steel Treating in a busy week at Cleveland. The morning sessions were held at the Hotel Cleveland and the afternoon ones at the Auditorium, where the metallurgical exhibition under the auspices of the American Society for Steel Treating not only occupied the arena of the Auditorium but completely filled the huge adjacent Annex. In the intervals of sessions the members thronged the exhibits but in the evenings the local attendance was so great that if the crowds had been any larger it would have been difficult to see the exhibits. With so many firms, both producers of metals and of equipment accessory to their production and use, it would be impossible to mention them -all and unfair to single out a few, since no two individuals' judgment would coincide as to relative interest and importance. In any case an exhibit is a thing to be seen rather than described, and these were well worth seeing.

Jan 1, 1929