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By N. Choi

The distribution behavior of cobalt, gold, and silver in nickel sulfide smelting was investigated between 1250-1300 °C under inert gas atmosphere. The distribution coefficients of these elements between nickel-copper-iron matte and silica-saturated iron silicate slag were determined as a function of matte and slag compositions. The effect of slag additives such as CaO, MgO, and Al2O3 on the solubility of cobalt, gold, and silver in slag was also investigated. It was observed that the distribution coefficients of these &nor elements were strongly dependent on matte grade. For cobalt and silver, the distribution coefficients decreased as the matte grade increased. However, the distribution coefficients of gold increased as the matte grade increased. The solubility of these minor elements in iron silicate slag was considerably decreased by the addition of basic oxides. Temperature dependence of the distribution of the minor elements will also be discussed.

Jan 1, 1995

By R. A. Wood, R. I. Jaffee, H. R. Ogden, D. N. Williams

Dispersion-containing titanium-copper alloys were prepared having mean free paths varying from 1.0 to 9.7 P. Tensile studies at room temperature and at 1000°F showed that little or no strengthening occurred when the mean free path exceeded 3 p. However, at lower values of mean free path appreczable strengthening was observed. A considerable amount of strengthening also resulted from copper in solid solution. DURING the past several years, an increasing amount of study has been devoted to dispersion hardening, an alloying process in which increased strength is obtained through the addition of a ran-

Jan 1, 1961

By K. P. Gupta, P. C. Panigrahy

The stabilization of the R, a-Mn, and 0-Mn phases have been studied in the Mn-Ti-Fe and Mn-Ti-Co systems. Iron and cobalt both appear to stabilize the (Mn-Ti) R phase to almost the sarne extent. The R-phase region was found to extend from the lowest e/a to slightly beyond the maximunz e/a limit known for this phase. But, while iron appears to stabilize the a-Mn phase, cobalt tends to stabilize the p-Mn phase. In the two systems manganese appears to get replaced by iron and cobalt in each of the mentioned phases. The instability of the a-Mn phase in the Mn-Ti-Co system and the /3 -Mn phase in the Mn-Ti-Fe system cannot be explained on the basis of adverse size effects because atomic diameters for both iron and cobalt (C.N. 12 at. diam) are ziery similnr and not much different from manganese which they replace. Qualitatively, the reason for the stability of the a-Mn and the p-Mn phases can be traced to the more favorable e/a ratio prevailing in the respective systems and to a competing tendency between the two phases. In transition metal alloy systems the o, p,P, R, a- Mn,' and p-Mn2 phases have been claimed as electron compounds. A large volume of work has been done to establish the criterion for the formation of the o phase but until very recently practically no systematic work was done on the a-Mn and the /3-Mn phases. A recent investigation on the P-Mn phase3 indicates the e/a criterion for p-Mn phase stabilization. Since the R phase was first known to appear only in certain ternary systems1 no detailed work was then possible for this phase. The R phase has been recently discovered as a binary intermetallic compound in the Mn-Ti~ and Mn-si~-' binary systems. The existence of binary R phases opens up the possibilities of studying the effect of alloying elements on the stabilization of the R phase. Of the two binary systems possessing an R phase, the Mn-Ti system appears to be more interesting because at a suitable high temperature it is possible to find the three electron compounds, the a-Mn, p-Mn, and R phases, side by side and it is possible to study the effect of a third transition element on these three electron compounds. For the present investigation iron and cobalt, so called B elements for the formation of electron compounds, have been used as the third element to study the stabilization of the a-Mn, P-Mn, and R phases. EXPERIMENTAL PROCEDURE The alloys were prepared by using 99.9 pct pure electrolytic Fe and Mn, 99.5 pct Co, and crystal bar titanium, supplied by Semi Elements Inc., New York and Gallard Schelsinger Mfg. Co., New York. Weighed amounts of the components were melted in recrystal-lized alumina crucibles in an inert atmosphere (argon) high-frequency induction melting unit. Titanium was made into fine chips for easy dissolution and a special charging procedure was adopted to avoid contacts of titanium chips with the alumina crucibles. Up to 20 at. pct Ti, the maximum titanium content in the investigated alloys, there was no visible sign of reaction of titanium with the alumina crucibles. With a careful control of melting time and temperature the losses were minimized and were always found to be below 0.1 pct. Because of such small and almost constant weight losses, the alloys were not finally analyzed. The alloys were wrapped in molybdenum foil and annealed in evacuated and sealed silica capsules at 1000" * 2°C for 72 hr and subsequently quenched in cold tap water. Annealed samples were examined metallographically and by X-ray diffraction. For all high manganese alloys oxalic acid solutions of various concentrations and 1.0 pct HN03 solution were found suitable as etching reagents. Best contrast between the a-Mn and the R phases could be obtained by using freshly prepared 60 pct glycerine + 20 pct HN03 + 20 pct HF solution. For high iron and cobalt containing alloys, especially for alloys containing the a-Fe, y-Fe, and P-Co phases, 15 cc HNOJ + 60 cc HC1 + 15 cc acetic acid + 15 cc water solution was found to be the best etching reagent. All X-ray diffraction work was carried out (using specimens prepared from annealed powders) with a 114.6 mm diam Debye-Scherrer camera using unfiltered FeK radiation at 25 kv and 10 ma. All calculations for X-ray diffraction work were carried out using an IBM 7044 digital computer RESULTS AND DISCUSSION The two ternary systems, MnTiFe and MnTiCo, were investigated near the manganese rich end, Figs. 1 and 2, and show some common features. In both alloy systems large extensions of narrow R phase regions occur at almost constant titanium contents. At titanium contents higher than that of the single phase R-phase alloys, the same unidentified X phase was found in both ternary systems. The extensions of the X phase close to the Mn-Ti binary indicate that this phase could be the TiMns phase. Too few X phase diffraction lines were present in the diffraction patterns to make positive identification of the X phase. In contrast to this similarity the two systems show opposite behavior in the extensions of the a-Mn and 8-Mn phase regions; while iron tends to stabilize the a-Mn phase, cobalt

Jan 1, 1970

By Alejandro Freyre B.

"El presente texto señala el proceso de explotación de la veta Shiusha situada en el distrito de las minas de Huarón. La veta es de origen hidrotermal, cuyo rumbo aproximado es E-W, y su buzamiento varía de 75º N en el Estea 85º N al Oeste, uniformizándose en los niveles inferiores en 85º :N. El eje mayor probable del depósito ( plano Nº. 1 '), tiene una inclinación de 25 º E. El depósito se extiende sobre una longitud de 1100 m, entrelas coordenadas 4600 - 57 00 E., pero la calidad y cantidad del mineral son variables en las tres dimensiones. Asimismo, se describe la prospección, preparación para corte y relleno, arranque, intermedias de los tres compartimientos y la aplicación de gradines descendentes vacíos."

Aug 20, 1963

By N. H. Mannakee

[Secretary's Note.—At the Spokane meeting of the Institute, in discussion of President Brunton's address on "Modern Progress in Mining and Metallurgy in the Western United States," and at the request of members present, Mr. Ayres gave an oral account of his new separator, which is here published as an independent paper, partly because of its inherent importance and partly because it describes an improvement which did not originate in the Western United States, and therefore does not fall, strictly speaking, under the title of President Urunton's address.—R. W. R.] A brief history of the growth of the anthracite-coal preparation will give a better view-point from which to judge the present problem of separating slate from coal. At the beginning of the commercial value of anthracite, 70 years ago, only the pure portions, or " splits," of the veins were mined and shipped to market, and without any preparation or screening other than the selection, while loading, of the glassy lumps, and the rejection of the fine material and the slate that had strayed accidentally into the coal. The next step was the crushing or breaking of the coal (hence the name "breaker" as applied to the preparation-building), and the sizing of it by means of bars or revolving screens. This stage of its development marked the advent of the " breaker-boy " as a slate-picker, with his ever-increasing capriciousness. As the richer veins or a splits " became exhausted and the market demanded a still greater output, the less-pure " splits " and the thinner veins were utilized to produce the coal. Carrying as they do a far greater percentage of impurities, particularly when removing the pillars, it became necessary to build new and better equipped preparation-plants. Finally, we are now at the highest stage of complicatioii yet known to the art of coal-preparation. We are dealing with varying specific gravities, frictional difference, hardness, structure, and form in the pieces of coal and slate coming from many different veins, and

Jan 1, 1910

By James P. Bennen

Limited efforts have been made to recycle/reuse-spent refractory materials in the steel and aluminum industries of North America. The driving force is usually part of a larger waste reduction program. -Economic or legislative forces have not been a driving force for spent refractory recycling/reuse. Past and current spent refractory recycling / reuse practices will be reviewed, with emphasis on specific programs at steel and aluminum companies. Program goals and progress of the joint Office of Industrial Technologies-DOE/Steel Manufacturers Association program directed at spent refractory reuse with electric arc furnace steel producers will also be discussed.

Jan 1, 2000

By Bruce A. Kennedy

The first light of dawn was appearing through the window of the giant Pan American Boeing 747 as we crossed the Irish Coast on course into London's Heathrow Airport While still over Ireland, the plane began its descent and a few minutes later an announcement on the public address system informed us that we were coming up on Lands End. Cornwall, and would then begin our final approach into London. Barely visible below through the WISP). clouds were the Seven Sisters Lighthouse and the rugged cliffs of Lands End and Cape Cornwall, the westcrnmost point of England. Start at Lands End To a displaced Englishman, it seems amazing that technology has brought us to a point where large jet aircraft use Lands End as the starting marker for final approaches into London. It was not so very long ago that we considered the eight-hour car journey or the 12- hour train trip from London to Lands End as a major undertaking. Today, with the 180,000-lb thrust of four engines, this enormous aircraft transports 350 or more passengers that distance in a matter of a quarter of an hour. The incongruity of the situation is that the technology leading up to the development of the powerful jet engines used on: today's aircraft started with the ; invention of the steam engine which found its first commercial use some 300 years earlier in the mines of Cornwall 20,000 ft below.

Jan 1, 1971

By P. V. R. Bhaskar Sarma, P. K. Sahoo, G. Roy Chaudhury

A process was developed to treat an ammoniacal leach liquor containing zinc using Di (2-ethyl hexyl) phosphoric acid (D2EHPA) as the extractant. The objective of this work was to develop a process package for the treatment of complex sulfide leach liquors. Zinc extraction could not be carried out directly from the ammoniacal solution in mixer-settler units because of crud formation and low extraction efficiency. After neutralizing the free ammonia with H2SO4, the extraction efficiency was only about 40%, due to the high concentration of (NH4)2SO4. To decrease the (NH4)2SO4 concentration, the free NH3 was steam stripped, and the resultant liquor was subjected to zinc solvent extraction. An extraction efficiency of 98% could be achieved by controlling the equilibrium pH. Stripping studies were also optimized after removing ammonia from the zinc-loaded organic. A continuous 100-hr operation that included extraction, scrubbing and stripping, was carried out successfully.

Jan 1, 1995

By M Elias

Management of risk has always been an integral part of successfully executing engineering and construction projects although formal recognition of the discipline of risk management is a relatively recent development. This paper describes the establishment and application of a proprietary business risk management framework for FluorÆs global engineering and construction business.

Jan 1, 2003

By Bekta? Uz

The study area is located between Orhangazi and Sapanca geographically known as Armutlu Peninsula (Figure 1). It is steep broken and mountainous with an area of 4000 km2. [ ] Economic marbles are investigated in regionally such as Orhangazi, Elmali, Menek?eyayla, Sapanca, Pamukova and they are seperated approximately 800 km2 (Figure 2). These marbles are massive, thick and dispersed as small sized outcrops in Armutlu Peninsula.

Jan 1, 2005

By C. B. Navalkar

The optimization of blast design under consideration is for the conventional driveways in under ground coal mines with respect to board & pillar workings in India. Basically The Blast Design includes following parameters: AA> Drilling Pattern. BB> Charging Pattern. CC> Material & Method Of Stemming. DD> Selection of type & quantity of explosives. EE> Initiation system & Blasting Sequence.

Jan 1, 2002

By J. W. Galpin, R. H. Allen

Controlled pre-grouting is a technique developed during a period of more than ten Years experience, in an effort to produce safer, drier and more economical mine shaft sinking. The technique involves a knowledge Of hydro-mechanics, both static and dynamic, and a series of specially formulated grout mixtures to obtain several desired results through precontrolled setting time. In general, the following procedures have been used to secure the best results in controlled pre-grouting: I. Before drilling is commenced, One Of two decisions is made: one procedure, a modified form of the Francois method, is to stage drill and grout, that is, drill a limited portion of the hole, then grout and redrill that section which has been grouted, progressing in stages until the required depth is reached. We prefer this method because no casing Or grouting packers are required in the bore hole. This eliminates the risk of losing them in the bore hole due to packer failure, which might result in the expense of drilling a new grout hole. Another feature Of this approach is that smaller drill holes may be effectively used, further reducing the costs. One drawback, however, is that because of the open and small size hole, it is impractical to attempt water draw-down tests. The second alternative is to drill the bore hole, (generally NX size), to the re-quire~ depth. he casing and grouting packer are placed in the bore hole at the lowest packer setting. A small, portable, power driven, swabbing device is used in the grouting casing to test the packer and remove mud or cuttings from the bore hole below the packer. The hydrostatic level is recorded and a close estimate or test is made of the quantity of water at each packer setting. Grouting progresses upward in a series of packer settings to the surface. Occasionally, casing is inserted in the bot-tom of the bore hole from within the mine, and water pressure and volume can be obtained in this manner. This is usually dangerous because of the unknown quantity of water. 2. The grouting, mining and geological engineers at the drill location make a detailed examination of the cores and also locate proper and firm grouting packer locations. A competent driller,s opinion should be given due consideration as to the character and condition of the bore hole. 3. Several samples of formation water

Jan 1, 1949

By C. W. Sherman, J. Chipman, H. I. Elvander

J. F. Elliott—This is an excellent piece of work and makes a chemical metallurgist more enthusiastic than ever about what can be done with multicomponent systems, if we have satisfactory data. I have a remark to make on the interpretation of fig. 5. First, I will comment on the problem of activities in solutions. The iron-sulphur system has in its phase diagram an intermediate solid phase FeS. The occurrence of an intermediate phase is normally associated with negative departures from Raoult's law over a portion of the activity curves in the liquid. (Perhaps it would be better to reserve the phrase "departure from ideality" to departures from Raoult's law line rather than to departures from Henry's law line). Fig. 5 indicates that the deviation of the sulphur activity curve from the Henry's law line is negative;

Jan 1, 1951

By J. C. Norman

The United States was the world's largest producer and consumer of boron compounds during 1994. According to US Bureau of Mines (USBM) estimates, boron mineral concentrate and chemical production in the United States totaled about 1.05 Mt (1.15 million st), yielding 560 kt (617,000 st) of B203, for a total estimated value of $370 million. This production level was about 2% less than 1993 revised figures. The United States continued to provide nearly all of its own boron supply while maintaining a strong position as a source of sodium borate products and boric acid for export. Domestic employment in the mining and beneficiation of boron products during 1994 was 900 people, about the same as in 1993. USBM estimated total world production of boron of about 2.3 Mt (2.5 million st), yielding 1.1 Mt (1.2 million st) of B203. World production during 1994 was about the same as during 1993. USBM estimates US reserves to be about 210 Mt (231 million st) of ore and world reserves to be about 630 Mt (694 million st) of ore.

Jan 1, 1995

By Zay Jeffries

Page Introduction............................. 474 Nature of Experiments ........................ 476 Materials Used in Experiments..................... 476 Description of Samples........................ 476 Details of Tests and Apparatus .................... 486 Determination of Elongation...................... 488 Determination of Reduction of Area .................. 488 Results of Tests........................... 489 Quantity and Arrangement of Amorphous Phase............. 497 Properties of Amorphous and Crystalline Phases............. 501 Intercrystalline Fracture........................ 530 Trans-crystalline Fracture....................... 531 Rupture ............................... 535 Explanation of Beilby's Results..................... 536 Mechanical Properties of Copper Wires................. 537 Mechanical Properties of Tungsten Wires................ 542 Mechanical Properties of Iron Wire................... 546 Effect of Diameter of Wire on Mechanical Properties........... 554 General Considerations on Properties of Metals at Very Low Temperatures .. 556 General Considerations on Physical Properties of Complex Alloys...... 557 Summary.............................. 559 Discussion.............................. 562 Introduction DuRing the period 1914 to 1916. the writer observed many times that tungsten wire could be drawn hot until it became brittle but on cooling to room temperature it became ductile again. In searching the literature for parallel cases. it was found that Beilbyl had produced hard-drawn wires of gold. silver. and copper that showed less than 1 per cent.

Jan 1, 1919

By Shengli Yang

Solid backfill mining, as a green mining technology, has the advantages of a higher resource recovery, less damage to the environment and the ability to dispose of waste underground. It has been applied successfully in the Xingtai and Xinwen mining areas in China. Strata behavior and the movement of overburden strata in this mining method are very different from fully mechanized longwall mining, which results in a natural caving, because the gob is filled with waste rock, fly ash and other backfill material. The results of field measurements showed that the periodic weighting interval of the main roof is longer; the magnitude of periodic weighting is smaller; the peak and zone of influence of the front abutment pressure are smaller than those in fully mechanized mining; that major deformation of mine roadways occurs within the influence zones of the abutment pressures; that the falling space of immediate roof is smaller, with the lower portion falling more sufficiently than the upper; that the main roof subsides slowly; and that the falling height of the overlying strata is greatly reduced.

Jan 1, 2011

By Emilie Williams

The Mouska Mine uses primarily shrinkage mining to extract the narrow veins that contain its mineralization. Mining is currently occurring on levels 12 to 14, reaching depths of 800 m below surface. Although the mine is not considered ?deep?, no backfill is available to fill empty stopes and certain areas remain open for over 500 m in height. As only narrow sill pillars remain to separate the levels, a highstress environment is created. Seismic activity was first observed when mining reached Level 11 (600 m deep) and has steadily increased since then. Seismic activity is associated with the highly-stressed sill and rib pillars; no geological structures have demonstrated significant seismic potential to date. In response to this increase in activity, pillar dimensions have been increased with depth and dynamic ground support has been installed. Seismic and pressure monitoring have been implemented, among other types of instrumentation. The following paper further describes the challenges associated with using conventional methods in the high-stress environment typical of the Canadian Shield, as well as several solutions implemented to mitigate these risks.

Feb 1, 2008

The high cost of sampling systems is largely due to the fact that indiv- idual mechanical type sampling units must be installed at the discharge end of ore/pulp pipelines, that is, at points where the pipeline discharges into pump sumps or the like. A considerable economic advantage may be obtained in the use of a samp- ling device that can be installed at any point in the path of the trans- porting pipe line. Initial tests on a vertical line with an injection sampler using iron ore concentrates reveal the validity of this type sample versus that taken with a mechanical sampler. A descrip- tion of the injection sampler shows its simplicity of installation, requir- ing minimum downtime on existing lines.

Jan 1, 1976

By D. C. Shelton, C. S. Ek

Corneille S. Ek (Assistant Professor in Ore Dressing, University of Liege, Liege, Belgium) — This is a very valuable paper, in that it shows how it is possible to take care of a multitude of laboratory routine tests, and derive from them successful modifications of flowsheets or of operating methods. The author and the Company appear to be test-minded and this is best seen through the case histories described. There are however some corrections to be made, and questions arise when one studies the paper. If all the equations are to be homogenous, one obviously has to write Eq. 4 On the other hand, it is difficult to accept the definition put on Eq. 7, for that equation, which represents the factor of transformation from tpd of solids to cu ft per min of pulp in Eq. 6, has nothing to do with conditioning. It is evidently assumed here that conditioning means, as Gaudin calls it,' modulation of collection. One would prefer, for Eq. 7, the appel-ation "pulp conversion factor". Eq. 8 and 9, giving the amount of reagent to be fed

Jan 1, 1965

By Kevin MacPherson

After 34km of roof bolted drivage the first fall of ground occurred at the Phalen Colliery in the maingate of the 8th East longwall panel. The fall occurred over the stage loader as the wall approached an area of poor roof geology. This area had developed a severe cutter since initial drivage and the longwall had yet to mine through 500m of even worse conditions. This paper describes the cause of the poor roof conditions, the use of polyurethane resin injection and cable bolting to re-stabilize the roof outby the fall, and the measurement of roof movement and performance subsequent to the continuation of mining under the rehabilitated roof.

Jan 1, 1999