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By C. Díaz, A. D. Dalvi, C. E. O'Neill

"Roast-reduction smelting (RRS) of nickel concentrate, combined with flash smelting of copper concentrate, was one of the process options that Inco considered as a means of meeting its 1994 sulphur dioxide abatement target at its Copper Cliff operations. RRS involves deep roasting the nickel concentrate in fluid bed roasters. The roaster off-gas is treated in a sulphuric acid plant, and the low sulphur calcine is reduction smelted with coke in an electric furnace to yield a sulphur-deficient matte. The latter material is converted to Bessemer matte in Peirce-Smith converters, with minimal evolution of sulphur dioxide, and the converter slag is reverted to the electric furnace. Excellent nickel and cobalt recoveries (Ire obtained. This paper discusses the development of RRS, including extensive commercial scale testing at Inco's Thompson Smelter, and its key operating parameters. IntroductionReduction of sulphur dioxide emissions has been a long-standing endeavour at Inco. At the company's Ontario Division, as shown in Figure 1, sulphur dioxide emissions were reduced from about 2 million to 685 000 tonnes per year over the period 1970-1985. Most of this impressive improvement was the result of a sustained research effort which led to increased rejection of pyrrhotite from the ore during milling while maintaining an acceptable nickel recovery. Between 1970 and 1985, the combined grade of the separate nickel and copper concentrates feeding the Copper Cliff Smelter increased from about 10070 to about 'lIJ0J0 Cu +Ni and the combined S/(CU +Ni) ratio decreased from about 2.8 to 1.65."

Jan 1, 1994

By Daniel W. H. Su

Underground roof geology reconnaissance is being conducted by CONSOL Inc. to enhance mine productivity. Often, roof instability within mine entries is the consequence of highly variable geology that cannot always be detected from information provided by widely-spaced surface core holes. Utilizing a combination of roof drilling data, geophysical logs, and borehole camera and fiberscope observations, roof geology mapping is conducted within longwall development entries in areas of specific concern prior to commencement of longwall mining, Depending on the uniformity of the site-specific roof geology, data point spacing along the longwall development generally ranges from one to five crosscuts. Surface core hole data are correlated with the roof geology mapped underground to validate the underground observations. Detailed roof geology maps can then be produced to enable ground control engineers and mine management to select cost-effective ground control techniques. However, this procedure is not necessary or useful in all situations and it is employed only when there is strong geologic evidence to justify a closer inspection.

Jan 1, 1999

This Bureau of Mines report summarizes the research, development, and evaluation demonstrations conducted by the Bureau of Mines under the Health and Safety Act of 1969 to improve the means of notifying miners underground, who are away from their own phone, that they are being called.

Jan 1, 1977

By William H. Bird

Over the past 14 years, the efforts of 2 companies and several individuals have outlined a major solfataric gold ore body in the Summitville district in the southeast San Juan Mountains of Colorado. The hard work of these years could not have flowered without a dedication to modern exploration methods, an intense interest in new theories of ore genesis, and a relentless discontent with the accepted geology of the Summitville area. To set the stage for this discovery period, it must be noted that it began 100 years after gold was first found at Summitville. It was the height of the "porphyry copper" era and gold was still not a part of the explorationists' portfolio. It was also a time of great intellectual stimulation. Theories were rapidly developing to relate different types of ore deposition and to place ore genesis within the fabric of plate tectonics. Summitville itself had just been linked to the newly discovered Platoro caldera complex and the Platoro lineament. This in turn related Summitville to the other San Juan volcanic field caldera ore deposits.

Jan 1, 1990

By R. F. Mehl, G. V. Smith

THE decomposition of austenite in steels, because of its immense practical importance, has been subjected to extensive study in recent years from the point of view of the mechanism of the process.1-3 Although much information has been acquired a number of questions, principally of theoretical interest, remain. One is that of the atomic-crystallographic mechanism by which each of the various reaction products forms. The isothermal reaction products of the eutectoid decomposition in plain carbon steels (to which this study is restricted) have conveniently been classified in three general groupings-pearlite, bainite, and martensite. Of these several products, pearlite and martensite have been studied extensively, but bainite has received only scant attention. As a result, the mechanism of the formation of pearlite and that of martensite are now fairly well understood while a great deal of uncertainty exists regarding bainite. PEARLITE Pearlite forms from austenite by the precipitation of alternate platelets of cementite and ferrite, which grow into the austenite matrix.2-5 The rate of reaction may be described in terms of a rate of nucleation and a rate of growth 2 3 Mehl and Smiths have attempted to determine the lattice relationships existing between the ferrite in pearlite and the parent austenite. Using a pole-figure method of analysis, it was found that a limited number of ferrite orientations resulted from the decomposition of a single grain of austenite; it was not possible,[ ]decide between two assumed ideal relationships, both of which appeared to account for the experimentally determined pole figure. It was definitely shown, however, that the relationship obtaining was quite different from that determined for the proeutectoid separation of ferrite.7 No attempt was made to determine the habit plane (matrix plane to which the precipitate lies parallel) of the pearlite lamellae. Belaiew8 earlier had stated that the number of directions assumed by the pearlite lamellae in a single grain of austenite was 12 (no details were given) and concluded wrongly, as Mehl and Smith' have pointed out, that the lamellae delineate the {210} planes of ferrite.* MARTENSITE It is known that martensite is a transitional constituent of body-centered tetrag-

Jan 1, 1942

By R. E. Morgan, Barkleym J. F.

"INTRODUCTION Wood burned for commercial heat and power usually is waste material from some manufacturing process. The amount of it reaches substantial proportions. It is estimated that over 50 percent of the timber cut for lumber becomes ""waste"" in the process - sawdust, shavings, trimmings, slabs, and bark. Woodworking manufacturing processes also produce much waste. The incentive to use this waste has resulted in much development of wood-burning equipment to produce heat and power. To answer general inquiries received by the Bureau, this publication covering developments along these lines was written. There is included a bibliography of additional information on the subject.COMPOSITION AND BURNING CHARACTERISTICS OF WOODThe approximate composition of moisture-free wood is, in even figures:PercentHydrogen 6Carbon 49Oxygen 44Ash 1Total 100This composition corresponds to about C6H1005. Moisture is essentially always associated with wood. Green wood contains approximately 30 to 50 percent moisture; air-dried or seasoned wood contains 15 to 25 percent and kiln-dried about 8 percent. Exposed to the weather, wood absorbs and gives off moisture depending on weather conditions and water contact.""Dry"" wood ignites relatively quickly and readily gives off volatile matter when heated. Long flames and smoke easily occur during burning. The burning action is substantially retarded, however, by appreciable moisture content; ignition is more difficult. When the moisture content is more than about 70 percent, an auxiliary fuel is required to maintain combustion. One of the main factors in the problem of the satisfactory and smokeless combustion of wood is its moisture content."

Sep 1, 1950

By J. S. Vanick

An extremely hard, tough, and strong, white or chilled cast iron has been applied for the past several years to industrial and mining services in which its unusual properties have been confirmed by its ability to deliver in many instances much better performance than plain chilled iron, or other wear-resistant materials. It is being produced regularly by alloying a good base composition of chilled or white cast iron with essentially 4 to 6 per cent of nickel and 1 to 2.5 per cent of chromium. Such a material can attain a hardness exceeding 600 to 750 Brinell as against 380 to 530 for corresponding grades of plain chilled iron. The strength is approximately doubled and the toughness significantly increased. These properties make it especially useful for many applications requiring a high hardness for resistance to wear, abrasion, attrition, deformation; to some extent to high compressive loading and to a lesser but important degree to corrosive action. A wide variety of commercial castings is being successfully produced from this iron, ranging in size from the small grain-grinding plates or burrs through medium-sized castings such as sand pumps up to large, heavy castings such as rolls for metal rolling or cement grinding. The composition of this white cast iron may be roughly bracketed within the range shown in Table 1.

Jan 1, 1933

By James L. Martin, Daniel J. Martin

The dendritic pattern of steels shown by deep etching is used extensively as a guide in the inspection and control of the great majority of steels used in ordnance construction and for many applications in industry. The value of macroexamination lies in the fact that it enables a qualified observer to make deductions concerning the general quality of relatively large pieces of metal. Not the least of these general characteristics is the nature and extent of the dendritic segregation in the steel, either in the cast condition or after mechanical or thermal treatments. Previous Work Detailed methods for macroetching were outlined by Yatsevitchl and have been standardized by the American Society for Testing Materials. A comprehensive study of the occurrence, origin, and the chemical and crystalline nature of the dendritic structure was given by Keshiam2 The marked persistence of dendritic segregation in nickel steels is fully recognized and has been discussed by Sauveur and Reed3 and by others. Very little, however, has been written on the effect of the various elements on the macrostructure of steels, and the purpose of this report is to submit evidence concerning the influence of chromium, nickel and molybdenum on the macrostructure of some 4 by 4-in. ingots cast and treated under closely controlled conditions. Methods and Results The ingots to be described were made in a 60-lb. high-frequency induction furnace at the Watertown Arsenal. Heats were made from a single lot of materials; were molten for the same length of time; tapped at approximately the same temperature into a standard mold preheated in each case to 150º ± 10º C.; and stripped and buried in ashes after 10 min. in the mold. Transverse disks were taken from the same location in

Jan 1, 1939

By Brien RT, O&apos

The work reported in this paper extends,-bhsb on the "Heat Hardening of Artificial Magnetite ;Pellets"., which was described at the- International Symposium on Agglomeration ;-sponsored by the American Institute. of Mining, Metallurgical and Petroleum Engineers at Philadelphia; U.S.A. in April, 1961. Whereas- that work was of a.,more basic nature, -serving to illustrate the suitability of artificialòmagnetites with various.admixtures, to the application of heat hardened pellets, on: this occasion the aim-is to illustrate the procedures-which were used-to- establish the dimensions of commercialòrecuperativ strands for Australian raw materials,The nature of the pellet feed, i.e. relatively uniform :spheres of4 3/8 in. - 7/16. in. diameter, makes it possible to use small scale static pots for test work. By the use of a closed system and the measurement of suctions, gas f lows, and temperatures through beds, the speed and heat requirements of the various stages of heat hardening can be measured, so: that for a specified quality of product estimates can be made of the broad design characteristics of a moving grate system. In practice of course it is .usual to correlate the data from this type-of :experimental 'apparatus with . existing production units upon which good operating data, in the statistical sense, are available.

Jan 1, 1963

Chromite ores have a long history of low pricing and for AustraliaÆs only chromite mine this has been a particularly tough challenge, especially as the mine is located nearly 400 km from the nearest port at Port Hedland. A stockpile of chromite fines (-16 mm) has been built up since 2003. The opportunity to develop a facility to treat this material to produce a chip (-16 + 1 mm) product and a sands (-1 mm + 45 micron) product was taken when the price increased to above US$140/t. A simple add-on plant containing a heavy media cyclone circuit for the chips and a spiral circuit for the sands was designed and developed. During construction of the fines plant the price of chromite reached a level where the payback for the entire project was less than eight weeks. Soon afterwards the price and the demand for chromite plummeted and the site was put on care and maintenance, except for the commissioning of the fines plant. This put considerable pressure on whether to continue to operate the plant or to place it in care and maintenance. Times of boom and bust provide management with almost totally opposite views. By not taking a conservative view on prices and costs, the effect of extremely low prices and minimal demand can be devastating to a good project. Designing and building plants with conservative costings in boom times gives a greater chance of keeping projects alive during the bust periods that tend to follow.

Jan 1, 2009

By J. Kochhar, Robert G. Cooper

"The Cape Breton Development Corporation is a federal Crown corporation which was formed in 1968. Initially, the Corporation had two divisions - the Industrial Development Division, whose purpose was to stimulate Cape Breton Island's economy, and the Coal Division with a mandate to phase out the operating coal mines. However, that strategy changed in the early 1970s with the Middle East oil crisis. As a result of that crisis, Nova Scotia Power Corporation adopted an ""off oil"" policy. Today, approximately 700/0 of Nova Scotia power needs are met by generation of electricity from coal. Therefore, since the early 1970s, emphasis has been on the rehabilitation of the Cape Breton coal mining business with the opening of three new mines.Today, Devco is solely a coal mining company which employs 3300 people.Physical DescriptionThe mines operate in the Sydney coal field which is located on the eastern tip of Cape Breton. The Corporation leases the deposit from the province of Nova Scotia and its leases cover all coal from the outcrop to the 4000 ft depth. The seams outcrop along the shoreline and dip beneath the ocean floor at dips varying between 5% and 100%.There are eleven seams, of which three - the Harbour, Phalen, and Hub - have been extensively mined."

Jan 1, 1990

By Kongfang Feng, Fei Ruan, Zhiyu Liu, Jieyu Zhang, Xin Hong, Shaobo Zheng, Jixu Wang, Jinyin Xie

"Mixing phenomena in smelting reduction furnaces with asymmetric side blowing were studied in this paper. Mixing phenomena in a smelting reduction furnace was represented as the mixing time by electrical conductivity measurements. Experiments were performed in a water model under various operating conditions to determine the effects of horizontal angle, radial angle, inserting depth, flow rate of the upper and the lower side nozzle, the included angle between the upper side nozzle, and the lower side nozzle on mixing phenomena in smelting reduction furnace. Comparing mixing time and mixing phenomena, the optimal conditions were obtained for an asymmetric side blowing process.IntroductionIn recent years, many countries have put forward development strategies for saving resources and environment-friendly, the development of various industries had to face its influence for resources and the environment .As we all know, the steel industry is a pillar industry of the global economy, in which ironmaking is an important part of it. In the modern ironmaking process, the blast furnace is regarded as the most important equipment and tool. But with the increasing scarcity of metallurgical coke resources and considering the environmental impact of such processes, metallurgists proposed the concept of smelting reduction. Smelting reduction processes to produce hot metal from iron ore and coal were being developed as a possible alternative to the traditional blast furnace. At present, a number of smelting reduction processes had been developed all over the world, they were mainly included COREX, HISMELT, FINEX, DIOS, etc."

Jan 1, 2012

By Y. C. Liu, R. H. Richman

From rolling textures of polycrystalline AgCl determined as a function of temperature, changes in the amounts of the individual textural components are correlated with temperature-dependent changes in glide geometry. The preferred orientations are influenced by the slip behavior as follows: 1) pencil glide, characterized by (110) slip directions and a greater participation in the deformation the higher the temperature, leads to a(012) fiber texture; 2) low-temperature deformation, primarily on (110) (110) systems, generates the {237}-(11, 9, 7) component; and 3) slip on {111}(110), comprising a significant portion of the room-temperature deformation, generates the {135}(211) and {110}(112) components. Typical re crystallization textures are also presented and briefly discussed. SPECIFIC relations between flow mechanisms in crystals and the individual orientations or components in deformation textures are necessary for a thorough understanding of the origin of such textures. Within each ordinary class of crystal struc- tures there is insufficient variety in the observed preferred orientations to permit direct and unambiguous correlation between flow mechanism and texture. A second approach to this problem is the correlation of textural changes with some known variation in glide geometry within one substance,1 In this paper, the latter approach is applied directly to a material in which there are distinct changes in the character of glide with changes in temperature. Silver chloride, although a nonmetal, is reported to exhibit slip,2,3 fiber textures,4 and rolling textures5,6 crystallographically similar to those of the well-studied fcc metals;7,8 in addition, there is a marked temperature sensitivity of the glide planes upon which flow occurs.3 Previous investigations of textures in AgCl unfortunately did not employ methods sufficiently sensitive to define possibly important minor components in the texture, nor did they utilize the temperature dependence of the glide systems. Thus, in order to clarify the effects of changes in slip mechanism, this paper reports a survey, using semiquantitative methods, of preferred orientations in rolled AgC1. Inasmuch as the influence of prior deformation texture upon preferred orientations after annealing is also of interest, some representative annealing textures are presented.

Jan 1, 1965

By Vincent Doyon

For several years, the GDD SSW EM Probe is being used in nickel?s mines in Canada and Brazil to define ore limits, reduce dilution and predict nickel grades. It is used with success to test most if not all percussion blast holes at all Falconbridge Mines in Sudbury and Raglan and all Inco?s Thompson mines. However, after testing the SSW Probe in other metal mines, we realized that EM conductivity does not define ore limits by testing blast holes for copper, zinc or gold. For non-conductive ores, no instrumentation is yet available on the market to reduce dilution, by outlining quickly and inexpensively the real shape of an orebody. To that effect, Instrumentation GDD Inc has developed a new revolutionary photonic probe that will make the reduction of dilution possible by probing blast holes. Once surveyed with the probe, a computer draws graphs of the ore grade as a function of depth for each blast hole. A contribution by Canada Economic Development made possible the development of this new technology. Canmet and Soredem also cautioned this technology developed by Instrumentation GDD Inc. This new photonic probe will allow: 1) to better understand the shape of the orebody 2) to raise the grade of the ore fed to the mill 3) a more complete extraction of the ore 4) to raise the competitiveness of mines

Oct 1, 2004

Abramovits, Charles, Student, Case School of Applied Science Cleveland, Ohio. '37 Abreu, Ovidio M., Student, Stanford Univ Stanford University. Calif. '38 Adams, Albert, Student, New Mexico School of Mines Socorro, N. M. '38 Adams, Benjamin C., Jr Address Wanted. '36 Adams, George H 44S2 4th St., Riverside, Calif. '36 Adams, Robert E., Student, Univ. of Wisconsin Madison, Wis. '38 Adkisson, J. F., Jr., Student, Agricultural & Mech. College of Texas, Box 2044, College Station, Tex. '38 Afshar, Hodji khan A., Amiranian Oil Co 10 Khiahan-i-Nusrat, Teheran, Iran. '35 Agvas, Cesar G., Student, Adamson School of Industrial Chem. & EngrgManila, P. I. '38 Ahlen, Louis S., Student, Univ. of North Dakota Univ. Sta., Grand Forks, N. D. '37 Albers, Francis C., Student, Univ. of Wisconsin Madison, Wis. '38 Alden, George P., Student, Univ. of Tulsa Tulsa, Okla. '38 Alexander, Donald B... Student. Univ. of Oklahoma, Sigma Nu House Norman, Okla. '37Alexander, Joe M., Student, Agricultural & Mech. College of Texas. Box 954. College Station. Tex. '38

Jan 1, 1938

By M. G. Corson

INFORMATION regarding the use of manganese alloys has hitherto been incomplete and available only from widely scattered sources. This paper attempts a systematic description of properties and uses of alloys other than manganese bronze, manganin and duralumin, which are probably the only non-ferrous alloys associated with manganese in the minds of most metallurgists.1 PROPERTIES OF MANGANESE Manganese can react either acid or basic; it is hard to obtain in the pure state; it has two different crystalline lattice structures, both of the cubic system, one stable above 850° C. and the other below 650° C., both coexisting in the intermediate range. Although the commercial product is hard and brittle, the pure metal seems to be ductile. In fact Zhemchuzhny, in Russia, was able to obtain ductile manganese and draw it to fine wires by the simple expedient of adding about 3 per cent. copper to the alumino-thermic product. Copper most probably brings the silicides, aluminides, nitrides and carbides present in the commercial product into a much less harmful form of distribution. One industrial use that can be foreseen for wrought manganese articles is as anodes for electrolytic processes in sulfate and nitrate solutions, particularly with high voltages. A practically insoluble skin of manganese peroxide is likely to form in such cases and an insoluble and strong anode material will be available. MANGANESE AS A SCAVENGER Because of its activity manganese might become the most efficient scavenger and refiner of copper, were it not for the fact that 0.01 per cent.

Jan 1, 1928

By Harrison Everett Ashley

Slimes are usually defined as all material passing a certain sized sieve, which is invariably the finest sieve employed by each metallurgist in his tests; 100-mesh and 200-mesh have been taken as the limits by different writers in recent volumes of the Transactions; 150-mesh is common practice. The reader of the first two volumes of Richards' is impressed by the inflexibility with which all grinding-arrangements are praised or condemned according as they make little or much slime. Until recently, one of the principal aims of the mill-man was to keep down the slimes. He was obliged to have separate apparatus for sand- and slime-treatment. The latter was sometimes puzzling and erratic. Often it was found most economical to omit treatment of the slimes entirely, or to store them in immense basins or heaps, waiting for possible future improvements in methods of treatment. Recently, improved processes of agitation and filtration have made possible the successful extraction of values from many slimes. The tendency, when the metal is exceedingly finely disseminated, is to cut out all sand-treatment and to slime everything. These processes have been almost entirely mechanical in their conception, and it is the object of the present paper to show that certain chemical considerations may greatly hinder or assist their successful operation. It has long been a source of dissatisfaction to chemists that their analyses fail to be of much help to the clay-worker; that it is a matter of common occurrence for clays of closely identical ultimate chemjcal constitution to show the widest possible divergence in physical properties.

Jan 1, 1911

By E. V. d’Invilliers

The position of these magnetic ore-mines, with reference to the county-seat, is shown in Fig. 1. They are situated on the south margin of the Great Valley, five miles south of Lebanon, and about midway between Reading on the Schuylkill River and Harrisburg on the Susquehanna River, in three prominent, contiguous hills, standing in front of the Mesozoic red shale arid sandstone hill country of northern Lancaster and southern Lebanon counties, and overlooking the great limestone plain to the north. The three hills, named respectively Big, Middle, and Grassy Hills, and separated from each other by two branches of Furnace Creek, range in a nearly east and west direction for a distance of about one mile. Their summits are respectively 870, 715, and 700 feet above tide. The railroad line opposite the base of Middle Hill is 575 feet above tide at Cornwall and 471 feet at Lebauon. These features are all distinctly illustrated in the contour-line map accompanying this paper, but are made still more clear in the relief. map, Fig. 2, comprising, as it does, about six square miles of territory contiguous to the ore-mines. This is a photographic plate of a model made by Mr. A. E. Lehman, from surveys of my own and Mr. W. F. Shunk. The model was built in layers of cardboard, each layer representing one 10-foot contour-carve line. The scale was the same as the original map, 400 feet= 1 inch, without any vertical exaggeration. The lowest contour-line is 530 feet above ocean level; the highest, 1075 feet. The center of the model was made the focusing-point of the view, which was taken—according to scale—51/2 miles north from and 24 miles above the focusing-point, looking southward. When first mined in the last century these hills exhibited smoothlyrounded surfaces, composed of soft weathered ore of great parity, beneath which lay the great mass of hard ore, constituting the whole

Jan 1, 1886

By Morgan Walker

Intermittent injection of gas in gas-lift pumping is a variation of the common practice in that the gas is delivered to the well for a short period, called the "on time," followed by a period during which none is admitted, called the "off time," instead of being admitted continuously at a constant rate or by intermittent flowing in which it is occasionally delivered to the well in just sufficient quantity to flow off the accumulated head of fluid. The term "gas" is used throughout this discussion but it should be remembered that in so far as the operation is concerned either air or natural gas may be used. The equipment at the well is the same as commonly used in gas-lift installations and gas may be admitted to either the tubing or the casing. It seldom occurs that all the wells on a lease can be pumped economically by intermittent injection from one header. Wells that have flow characteristics which permit their being handled together have their intake lines grouped at a central compressor station. Well groups may consist of two or more wells. The total volume of gas delivered by each group of compressors goes to one well at a time through a quick opening valve, each well connected to the header receiving its charge of gas in turn. Special cases may require a deviation from this arrangement. The distribution of the gas to the different wells is effected by an automatic timing device which operates quick-opening valves on the intake lines. The timing mechanism may be actuated by electricity, liquid or gas pressure, The essential factor in the operation of the timing mechanism is that as one intake valve is closed another must be opened. Water-operated Timing Device Timing devices operate the intake valves either directly, or indirectly by pilot valves. Of the former type one that is operated by water and has given satisfactory service is shown in Fig. 1 and can be made on the lease. The horizontal cylinder is a piece of 10-in. casing about 7 ft. long, closed at each end and free to oscillate about a fulcrum at the center.

Jan 1, 1929

By Brian Mattie

Overview ?Overview of the mining area ?Description of the mining phases ?Risk assessment ?Design criteria and description for freeze drifts ?Freeze wall design ?Raisebore mining Four Main Phases: 1.Development of freeze drifts on the 520 and 590 levels 2.Freeze drilling and ground freezing to isolate the Zone 4 North ore body from water bearing sandstone. 3.Develop raisebore and extraction chambers including access drifts and ramps under freeze protection. 4.Start raisebore production mining of the Zone 4 North area.

Nov 1, 2011