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By Alex Lowson, Dan Tempelis

The Riverside Badlands Tunnel segment of the Metropolitan Water District of Southern California’s Inland Feeder Project, was lined with a segmented concrete primary lining and a welded steel final lining with the annulus filled with Low-Density Cellular Concrete (really a grout). The paper describes a numerical modeling technique that was developed to determine safe grout placement procedures to avoid pipe flotation, and shows the relationship between flotation and the rheology of the liquid grout. Design details of the steel liners are often not well suited to grout placement, and recommendations are given on how to improve this.

Jan 1, 2003

By F. Louis Grammer

The iron industry has been so markedly the cynosure of all eyes, that a sense of weariness has overtaken many on-lookers, and a new wonder is desired. While the commercial phase of the iron industry has necessarily engrossed the public attention and probably is the more worthy of record, still the mechanical and metallurgical phases have recorded conspicuous advances and merit attention. In order to appreciate the present condition of blast-furnace practice, it is necessary before enumerating the advances made during the past decade to give a brief discussion of the tendencies in the methods of administration as well as the conditions governing supremacy, for these factors have modified the aims of the manager. It might also be well to apologize for a record of the advances made during such a short period as a decade, were it not that, for the individual, time is marked as much by the impressions recorded on the brain as by the jumps of the second hand of a watch. Furthermore, this article is written in order to carry out a project of the late Dr. Egleston, to have a record made each decade. I regret that the data collected by him, and forwarded to me, end with 1896, and therefore do not include the interesting results which followed the introduction of Mesabi ores. The perusal of the notes is melancholy reading, somewhat like the feelings we experience in going through a graveyard. It is a record made up of so many plants, which have ceased to be factors in the iron world, if they are not entirely moribund. Historically, they would be interesting, emphasizing as they do the abnormal and somewhat overestimated importance of furnace lines, taken without proper reference to volume of blast and nature of stock used. I regret, however, that the time at my disposal does not permit of this presentation.

Jan 1, 1905

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Jan 1, 1990

By Homer G. Turner

Coals, other than anthracite, have been so thoroughly studied under the microscope during recent years, that we now know what kinds of plants and what parts of plants form the bulk of lower rank coals from peat to bituminous coal. The microscope has also shown the state of preservation of such vegetation as well as the nature and distribution of products of plant decay. These and further details have been ascertained mainly through the employment of two methods of attack, section cutting and maceration. Anthracite has failed to respond to these methods, so well adapted to the study of lower rank coals and, therefore, has been neglected by investigators to such an extent that there is much doubt as to its microscopical characteristics. The object of this paper is to lift anthracite from its realm of obscurity by demonstrating the wealth of microscopical detail that is revealed when reflected light is used on a properly polished and etched surface and, further, to show the relationship between anthracite and bituminous coal. Technique The method adopted in this investigation is similar to that described in an earlier paper.' Because of slight modifications recently made, the process is again described. It consists, briefly, of etching a polished surface of coal with heat. Although pieces of various sizes and shapes are used, blocks of coal about 2 or 3 cm. square take the most uniform polish and are large enough to be handled with ease. Larger pieces can be used if one has the equipment for polishing them and they rnay be desirable when one wishes to study some particular form that extends for some distance through the coal. Large surfaces, however, require greater care in polishing and etching; for this reason, they are not recommended for ordinary work.

Jan 1, 1925

By l. Bokányi

The Tóth adsorption isotherm-model was derived and has been widely used for the inhomogeneous solid surfaces. The three-parameter isotherm incorporates the effect of the interaction between the adsorbed substances as well. All classic isotherms can be clearly derived from this one. Bio sorption is the sequestering of dissolved components, i.e. metals from aqueous environment by living or dead biomass. The mechanism of the bio sorption is rather complex and predominantly refers to the affinity of the chemical functional groups: acetoamido groups of chitin, structural polysaccharides, amino and phosphate groups in nucleic acids, amino, amido sulfhydryl and carboxyl groups in proteins, hydroxyls in polysaccharides, sulphates, etc. towards the soluted substances, i.e. heavy metal ions. The physisorption, as well as the micro precipitation also play a role in the bio sorption mechanism. The description of such a complex process can be done by a model reflecting this complexity. According to our experimental results obtained using algae and immobilised algae for the sorption of heavy metal cations, the most appropriate model for such a description is the Tóth-isotherm, the parameters of which can be interpreted. Flotation process is also a very complex one, the overall result of which depends on the partial results of many micro processes and parameters. The particle interaction which very often takes place in the flotation systems makes the phenomenon even more complex. The flotation kinetic model with particle interaction was already introduced by author in 1994 and further developed in 2000. In this paper based on the experimental results obtained with metallic particles in case of recycling flotation the applicability of the Tóth-equation as an alternative flotation kinetic model for the systems with particle interaction is proved. The applicability of Tóth-model in mineral processing demonstrates again its universal character and the great talent of the late József Tóth, great Hungarian chemist. Keywords : Toth isotherm, biosorption, Langmuir, Freundlich

Sep 1, 2012

By R. L. Templin

THE increasing use of aluminum and its alloys in commercial fields has demanded a better understanding of their machining properties. This fact is exemplified by problems that have arisen in the automotive and airplane industries, but many in other fields might be cited. As pure aluminum and its alloys in their various commercial conditions show appreciable differences in their machining properties, it is not surprising that quite divergent solutions have been offered for the machining problems encountered. However, if the fundamental requirements of the most suitable cutting tools for these metals are understood, these machining problems lend themselves more readily to satisfactory solutions. Since the machining of free cutting brass and mild steel is understood by most persons accustomed to working these metals, it may serve our purpose better to first make a general comparison of the tools more commonly used in machining these metals with the tools most suitable for machining aluminum, then proceed to a more specific discussion of the individual stools.

Jan 1, 1927

By A. Eilers

COMPOSITION OF CHARGES AND CONSUMPTION OF FUEL AT VARIOUS WORKS. A MARKED peculiarity of most of the smelting-works of the Far West is the looseness with which accounts of the operations are kept. Indeed, probably over half of the works do not keep any detailed accounts at all, the yearly gross statement of profit or loss being considered sufficient for all purposes. The reasons for this must apparently be sought in the as yet unsettled state of all business relations, and in the deplorable fact that only in isolated cases educated metallurgists are in charge of the smelting-works. Continual and regular assays of the ores, by-products, and slags, are almost unknown, so that it is impracticable to ascertain, even approximately, the losses in the smelting processes. Of cases where regular accounts are kept of the quantities of ore smelted, of the composition of charges, and of the fuel consumed, I know only two or three. Under these circumstances it is extremely difficult to collect figures which cover the operations for a considerable length of time, and which are so valuable for the metallurgist, who wishes to get an insight into the economy of smelting operations, as shown by practice. Figures obtained by personal observation, which can of course cover only the brief space of the visit of the travelling metallurgist, must, therefore, be made to replace the more valuable data. The writer has had occasion, during the last and the preceding summer, to visit the larger number of the Western lead-smelting works, and offers, in the following pages, such data relating to the economy of lead-smelting in the blast furnace at various works, as he has been able to obtain. The only object in doing so is to place these figures on record, so that they may be from time to time supplemented with other data, which are now wanting. I. EUREKA CONSOLIDATED COMPANY'S SMELTING-WORKS. These works smelt the ores from the mines of the same company on Ruby Hill, Eureka, Nevada. The supply is almost unlimited,

Jan 1, 1873

By Bill Gray

Jan 1, 2008

By D. Doyle, T. Cienski

"This paper presents and discusses the results of a detailed study conducted on the subject of energy consumption in the comminution of industrial minerals. The study was based on pilot circuit testing, plant operating data collection, detailed equipment data and literature research. The areas covered by investigations include: high efficiency classification; air classifiers for cement grinding circuits; grinding aids in dry grinding; and dry grinding circuit control based on particle size measurement. Results obtained indicate a large potential for the reduction of energy consumption, in particular in the cement clinker grinding circuits. Better classification techniques and correct application of grinding additives can significantly reduce power used per tonne of product and also substantially increase grinding circuit output."

Jan 1, 1992

By Charles A. Stetefeldt

This treatise is the sequel of a paper on "Russell's Improved Process for the Lixiviation of Silver-ores," etc., read at the Chicago meeting, in May, 1884, and published in the Transactions, vol. xiii., page 47. The facts it presents are principally compiled from Mr. Russell's notes on his practical experience gained in various places where the Russell process has been introduced. For a complete understanding of this paper a perusal of my former one is desirable, as can be seen from the frequent references here made to it. All silver-ores that do not carry a large percentage of lead or copper can be treated by Russell's process with success and economy. I do not mean to create the impression that from ores containing considerable quantities of lead and copper a high percentage of the silver cannot be extracted by this process. Such ores, however, will, in many localities, be reduced to better advantage by smelting. In case lead-bearing silver-ores are suitable for concentration, it may be profitable to concentrate the ore by Krom's dry system, obtaining a smelting-product high in lead, and to lixiviate the tailings and the dust. This plan has been adopted in a mill recently erected in Cortez District, Nevada. The dry system of concentration deserves the preference because it delivers the tailings and the dust in a condition ready for chloridizing-roasting. In wet concentration the drying of the tail ings would be expensive, and there would be a considerable loss of silver in slimes. Oxidized ores, containing silver chloride and lead minerals, may be lixiviated after crushing, and the tailings may be concentrated for lead. In this case wet concentration would be most suitable. This has been done at the Old Telegraph Mine, Utah. I would give, however, the preference to dry concentration in all cases which, of course, requires that concentration should precede lixiviation. The Russell process is also adapted to the treatment of tailings resulting from ores which have been worked either by the old

Jan 1, 1887

By R. F. Mehl, C. S. Barrett, A. H. Geisler

THE mechanism by which the super-saturated solid solution of 20 per cent silver in aluminum decomposes has been reported in two previous publications. 1,2 The analysis of streaks in Laue photograms showed that thin platelike particles (the so-called Guinier-Preston aggregates) form upon {111} matrix planes in the early state of decomposition.1 The size of these particles is larger, the higher the temperature at which they form in accordance with nucleation theory;3 at all temperatures they increase in size with aging.2 When they have grown thick enough to afford three-dimensional diffraction, powder X-ray photograms show that the structure is not that of the equilibrium precipitate y but that of a transition lattice ?'. Since this is also platelike in shape and also lies upon the {111} matrix planes with the {110} direction in the matrix parallel to the {11.0} direction in ?', it seems likely that the original platelet particles are merely ?' in an early stage of formation, and thus finely dispersed. The atomic spacing and pattern on the {00.0} plane in ?' are identical with those on the {111} matrix plane to which it lies parallel, and since comparable directions in the two planes are parallel, the lattices are thus coherent at the interface; an analogous coherence has been found in aluminum-copper alloys.3 The structures ?' and y are both close-packed hexagonal and are oriented alike; they differ only in interatomic distances. Consequently, ? ' is regarded as y strained from its ordinary dimensions by the lattice coherency between it and the matrix.2 The lattice movements that transform the matrix to the equilibrium precipitate appear to be very simple.2 The mechanism of precipitation in this system is simpler and is more precisely known than that in any other system,2,4 hence the system should be a profitable one for the difficult task of correlating property changes with structural alterations. The present report provides additional studies on powder X-ray diffraction from alloys of 10 per cent, 20 per cent and 30 per cent Ag, and presents the correlation of crystallographic changes with changes in microstructure, Brinell hardness and electrical resistivity of the three alloys. PREPARATION OF SAMPLES AND EXPERIMENTAL PROCEDURE The preparation of the 20.2 per cent Ag alloy has been described.2 Alloys containing 9.9 and 29.7 per cent Ag were prepared from 99.97 per cent Al and 99.99+ per cent Ag using a similar procedure. Rolled

Jan 1, 1943

By Arthur Crowfoot

Page IntRodUction ................... The Round Table in Lake Superior Practice .........420 Early Use of Revolving Round Table in Butte District...... Use oF the Round Table at GREat Falls foR Sand-Slime Feed ., . The Round Table for Fine Slime........,.... Construction of Slime Plant at Great Falls..... '..... 424 Tests on Wood, Linoleum, and Cement Decks.........426 Central Feed Apron Removed ....'......... Re-treatment of Round-Table Tailing........... Determination of Conditions for Round-Table Treatment of Slimcs ... 430 Variation in Slope of Round-Table Deck........ ,... The Steel-Frame Cement-Deck Round Table ........ Tests on Cement and Canvas Dock Surfaces ..: ..... Conoidal Deck Round Tables............. Results with Sand-Slime Feed on Conoidal Deck....... Conclusions from Preliminary Tests on Conoidal and Conical Decks ... 446 Discussion of Results of Four-Day Test on Conical and Conoidal Decks . 452 Discussion of Results of Eight-Day Test.......... Qualitative Sampling of Concentrates Across Conical Deck.... Summary of Slime-Plant Practice............ Suggested Flow Sheet for Slime Classification and Treatment.... Conclusion...................467 Introduction The principal object of this paper is 60 presest, data on the development of the revolving convex round table as a concentrator for the through 0.07-mm. slimes from the ores of the Butte district, although some brief notes on the earliest recorded use of this type of concentrating table in the ore-dressing plants of the Lake Superior region and of the Butte district are also presented. The revolving convex round table belongs to the class of concentrating tables known as film-sizing. tables, these tables using the relative transporting power of a film, or thin sheet of water, as it flows over a quiet inclined surface, to separate the minerals of a sorted product. The grains of heavy mineral move down the slope of the table deck slowly, or, in some cases, not at all, after the initial force of the feed entry VOL. XLIX.—27

Jan 1, 1915

By Wayne D. Goodfellow, William M. Luff, Steven J. Juras

Brunswick No. 12 is a vent-proximal massive sulfide deposit that formed above a feeder pipe with associated hydrothermal alteration. Because of the replacement of bedded sulfides deposited above the hydrothermal vent, individual sulfide lenses show the following vertical and lateral zoning outward from the vent complex: massive pyrite-pyrrhotite-ehalcopyrite core interlayered pyrite-sphalerite-galena (pb-Zn ore zone) - bedded pyrite. The feeder zone which underlies the Cu-rich core consists of an anastomosing network of pyrite-pyrrhotite-chalcopyritequartz veins with variable and generally minor contents of ferroan carbonate, Fe-rich chlorite, sphalerite, galena and arsenopyrite. Hydrothermal alteration of felsic igneous rocks hosting and adjacent to the feeder pipe is represented by an inner zone (zone I) characterized by sulfide stringers, Fe-rich chlorite, muscovite, quartz, and ferroan carbonate that formed at the expense of feldspars and what was probably glass; outer zones (II and III) are represented by Mg-rich chlorite and muscovite formation, and the albitization and silicification of K-feldspar. Accompanying these alteration trends is a marked decrease of Na + Ca, and an increase in Fe + Mg + C03 in zone I, and increases in Mg + Na in the outer zones. The classic zoning of metals within the sulfide lenses, the formation of a feeder pipe below the vent-proximal sulfide core, and the hydrothermal alteration of felsic volcanic rocks cut by the feeder pipe all support a vent-proximal origin for the Brunswick No. 12 deposit. Furthermore, restriction of sulfide stringer mineralization to the footwall sequence, the folding of the stringer zone by an F, fold, and the difficulty of long distance mass transfer of metals from the sulfides into the host rocks all argue against a tectonic origin for the stringer zone. All of the evidence indicates that the feeder pipe formed during the ore forming hydrothermal event, but has been distorted and in some areas detached from the overlying massive sulfides during subsequent deformation.

Jan 1, 1992

By M. Machina

Anew approach to the use of projectiles for rock fragmentation uses recently-developed technology to optimize projectile shape and composition to achieve the desired type of breakage. Projectiles can also be made of various materials, as determined by the requirements of downstream processes. This paper describes laboratory tests with an 21-mm (8-guage) gun, and field tests with a 60-mm cannon.

Jan 1, 2003

The 2-4D window shown above is the base startup window which allows you to begin a new project. ??Setting up the project is the first step ??The next step is to setup the properties to be used in this project

Feb 1, 2008

By Edmund J. Flynn

My subject Is Industrial Relations. Thus, I may appear as an intruder at this annual meeting of the Society of Mining Engineers. But I am no more an intruder here than is Industrial Relations in the day-to-day functioning of an engineer either in a staff or a line job. Engineers deal with people, as well as with blueprints, organizational charts, production data, etc. Where you have people, you have emotions, gripes, wants - real or imagined. Or you may just need some people or, at the other end of the pole, you may want to free yourself of people. But whether it is the wants or the needs, the pleasant or the unpleasant aspects of dealing with people, an Industrial Relations Department within an organization is there to help with these human relationships. This is the point for a definition of terns. Reference has just been made to "dealing with people? and to "human relations." This is, precisely the area in which Industrial Relations operates in the western Mining Divisions of Kennecott. In other organizations, what we refer to as Industrial Relations, may be called personnel relations, personnel administration, employee relations, or labor management relations. In our opinion the term Industrial Relations is best descriptive of the activity because it embraces the broad field of human behavior, reactions and satisfactions growing out of an individual?s entire employment relationship including his hiring, his lifetime on the job, and his termination. This is an individual?s industrial life. However, despite the use of the word "industrial", we are ever conscious that Industrial Relations is limited to human relations. Operational activities and decisions relating to the mining, milling, smelting and refining processes are for the line organization. The Industrial Relations interest in these line organizations activities and decisions relates only to the impact they nay have on employees - on people generally within the organization.

Jan 1, 1959

By James P. Kimball

THE object of the present memoir is to put on record some practical experiments by the writer in smelting a silicious native magnetite with no other flux than the silicates of its own gangue: This work was undertaken in the spring of 1878 for Messrs. Naylor & Co., of Boston, to whom I am indebted for the privilege of here communicating its results, these having hitherto only been simply announced.* So far as I am aware these are the first instances of the kind in this country that non-calcareous; or rather non-carbonated, magnetites have successfully been used strictly alone as self-fluxing ores in the blast furnace; that is, without the addition of calcareous flux in the form either of limestone, quicklime, calcareous ore, or basic (calcareous). slag. Previous to the spring of 1878, when the Chateaugay magnetic ore was first brought to my notice, its use had been limited to Catalan forges, after "separation" at the ore bed. The blooms and billets made from it in the several forges of Messrs. Weed & Williams, and of Mr. Williams, were well known in the trade as among the best in the market. The Chateaugay ore beds proving of great magnitude, and the ore exceptionally low in phosphoric acid, it commended itself for blast-furnace purposes to Messrs. Naylor & Co., who employed nee to blow-in the charcoal furnace at Pittsford, Vt., on this ore in the spring of 1878., a previous trial of this ore in the same furnace in the fall of 1877 having proved abortive. This was therefore the first time that Chateaugay ore was successfully smelted in a blast furnace, although since well known as a blast-furnace ore possessing superior and exceptional qualities. The Pittsford furnace, although rebuilt in 1844, and subsequently improved by the former owner, the late J. Prichard, is one of the few furnaces of the old type with open breast (Sumpfofen) still active in this country. Its improvements on furnaces of the period, * Bulletin American Iron and Steel Association, XII, 1878, 132, 156.

Jan 1, 1881

By K. Robert Dorman

This Bureau of Mines report describes laboratory and field experimentation in building mine ventilation stoppings, air-door frames, and fan bulkheads with a civil construction technique. Shotcrete is applied to a free-standing, three-dimensional wire-truss panel, which is easily cut and rapidly erected. In mines where shotcrete equipment is available, this technique should be faster and cheaper than conventional block-and-mortar or monolithic concrete construction.

Jan 1, 1980

By Leonard Grimshaw

DIFFUSION Of carbon from gases into iron has been the object of much research, because of its long recognized importance in carburizing processes, but the direct diffusion of carbon from steel into iron has received relatively little attention. Because of the increasing use of clad metals in industry, direct diffusion from steel into iron is becoming of practical importance. Therefore, the object of this investigation was to study the diffusion of carbon from several different kinds of steel directly into relatively pure iron, realizing that elements in the steels other than carbon might influence the rate of carbon diffusion. The previous work on diffusion of carbon into iron has been consider-able, and includes many reports in foreign languages. This work has recently been well reviewed by Mehl1 and Krynitsky,2 and the reader is referred to their excellent bibliographies.

Jan 1, 1937

By Michael Traylor, Michael Jatczak, Brett Robinson

The Detroit River Outfall No. 2. is an effluent water conveyance system linking the Detroit Metropolitan Wastewater Treatment Plant to the Detroit River. The 6.4m (21ft) finished diameter tunnel extends 1,890m (6,200ft) east from the bottom of a 91m(300ft) deep, 9.2m (30ft) diameter drop shaft. At the eastern terminus of the tunnel, six Riser Shafts connect the tunnel to diffuser heads on the riverbed. The tunnel runs through a highly fractured Limestone formation capable of producing high levels of groundwater in?ows and Hydrogen Sul?de gas. Control of this water and gas was a theme which ran through the entire Project’s design and construction. This paper will provide an overview of each portion of the Project’s construction, including the Entrance Shaft, Precast Concrete Segments, TBM Tunnel, Pre-Excavation Grouting Methods, and the Riser Shafts.

Jan 1, 2003