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By Mingming Zhang, Mallikharjuna R. Bogala, Ramana G. Reddy

Steelmaking desulfurization slag samples were characterized using chemical, X-ray diffraction (XRD), scanning electron microscopy (SEM) and energy dispersive spectrometry (EDS) methods. The objective of this work is to investigate the occurrence of sulfur and phosphorus components in the slag samples and to identify their origin and associations with the iron phases. Thermodynamic calculations results confirm the presence of phosphorus and sulfur components in the slag sample at high temperatures (1400 to 1800oC). The main constituents of slag include Ca3SiO5 (28.1%), MgO (9.31%), Ca3(PO4)2 (9.18%), CaS (8.39%) and CaO (5.68%). The major phosphorus and sulfur components of the slag are Ca3PO4 (99.2%) and CaS (79.3%) respectively. Characterization studies indicate the presence of microparticles of different sizes and shapes in the slag sample. Elemental analysis of these particles confirm the presence of major elements (O, Mg, Al, Si, S, Ca and Fe) in the slag sample.

Jan 1, 2015

By Zhigang Zak Fang, Michael L. Free, Jaehun Cho, Syamantak Roy, Amarchand Sathyapalan

Leaching characteristics of impurity removal from the Upgraded Titania Slag (UGS) using hydrochloric and boric acids has been investigated. Specifically, this study has focused on removal of iron oxides from the UGS that has been reduced by hydrogen gas and magnesium at 750oC for 5 hours. Reduced UGS is mainly composed of titanium hydride and impurities like iron oxides, silicon oxide, aluminum oxide, and magnesium oxide. The concentration of hydrochloric and boric acids and the leaching temperature have been chosen as the prime variables to identify the optimum conditions and leaching characteristics for removal of iron oxides. It was observed that under the constraint that 1 wt % of titanium hydride loss is the maximum amount tolerable, 0.1M HCl with 1M boric acid and 90oC are the most effective parameters for iron removal from the reduced UGS. Also, the overall rate of reaction seems to follow interfacial reaction controlled kinetics. The calculated activation energy of the reaction is 73.90kJ/mol.

Jan 1, 2016

By J. Wendt, P. R. Sahm, T. Uloth, M. Weck, F. Foertsch

"The FEM program systems CASTS (Computer Aided Solidification TechnologieS) (1) and FINELF (FINite ELement Frontal Solver) are used to optimize a thin walled die casting. After a short description of the programs it will be worked out how to use them not only for simulating solidification processes but also for optimizing the design of workpieces. The calculations will be done for an automobile's support bracket which is manufactured in a well known car factory in Stuttgart, FRG.IntroductionAt the Aachen Foundry Institute the software package CASTS was developped to simulate solidification of castings. In order to optimize the whole manufacturing process it does not appear sufficient any more to take into account only the specific aspects of casting. For instance one has to consider additionally the stress situation under service load. For this reason the Foundry Institute together with the Aachen WZL-Institute (Machine Tool Laboratory) and the car factory mentioned above started to probe into a first step in that direction. Figure 1 shows the support bracket which shall be optimized."

Jan 1, 1986

By Harold L. Hinds

The refining of precious metals from steel wool cathoodes is completed by one of two methods: 1) By direct fire smelting or: 2) Acid treatment of the cathodes to dissolve the steel wool and then followed by fire smelting. To further the refining of the cathodes, the Miller Process and the Wohlwill Process are used.

Jan 1, 1981

By R. R. Rogers

Introduction The subject of cathodic protection is not new. In 1824 Sir Humphry Davy, in publishing the results of his investigations for the British navy, pointed out that copper could be protected from sea-water corrosion by connecting it electrically with zinc or iron. Since that time much work has been clone in this field, particularly in the protection of metals from the action of sea water, neutral brines, and treated and untreated waters. Special mention should be made of the successful protection of underground pipe-lines which formerly were badly corroded by the water in the ground. So far, magnesium alloy and zinc anodes have been the most popular. However, fairly recent work has indicated that aluminium anodes will give good service under certain conditions. The principle of cathodic protection has been applied extensively in coating steel articles with zinc and in cladding aluminium alloy sheet with pure aluminium. A valuable discussion of the fundamentals and applications of cathodic protection recently was presented in the Corrosion Handbook. A useful list of references was included in the article.

Jan 1, 1949

By Zhanjun Wang, Mei Zhang, Zuotai Zhang, Min Guo

In this study, the viscous flow and crystallization behavior of CaO–SiO2–MgO–Al2O3–FetO–P2O5–TiO2 steelmaking slags have been investigated over a wide range of temperatures. The results indicated that the viscosity of the slags slightly decreased with increasing TiO2 content. The constructed non-isothermal continuous cooling transformation (CCT) diagrams revealed that the addition of TiO2 lowered the crystallization temperatures. This can mainly be ascribed that the addition of TiO2 promotes the formation of [TiO6]-octahedra units, thereby MgFe2O4–Mg2TiO4 solid solution is formed. Moreover, the decreasing viscosity has a significant effect on the diffusion of ion units, such as Ca2+ and [TiO4]-tetrahedra, from bulk melts to crystal-melt interface. The crystallization of CaTiO3 and CaSiTiO5 was therefore accelerated, which can improve the phosphorus content in P-enriched phase.

Mar 1, 2017

By V. O. Tenorio, K. W. B. Requist

As the mining industry begins efforts to examine the feasibility of extraterrestrial resource utilization, the extraction and processing of icy regolith containing water and other volatile materials will be the initial focus for future expansion of capabilities. Pure water is essential for human consumption, and a source of oxygen and hydrogen. The latter, along with the volatile materials, lend themselves to the creation of fuels that may be used for further space exploration at distances not currently feasible. For any extraterrestrial scoping project, the transport of materials to geoscientists remains virtually impossible. Therefore, analysis must be done in-situ, possibly millions of miles away from the nearest human. To address the need for geologic resource estimation in the absence of geoscientists, an infrared framework has been developed for the analysis of water ice content in simulants of permanently shaded lunar regolith. This framework relies on a convolutional neural network model for the rapid analysis of percent water ice content in samples, at which point standard geostatistical methods may be employed.

Feb 1, 2023

By J. R. Guard

Development of electrical power in coal mining has been an outstanding example of adaptability. It has accommodated itself to new inventions, changing mining methods, increasing demands, increasing safety requirements and many other new conditions. With the appearance of the continuous miner in the mining machinery picture, those engineers interested in the application of electricity to mining have been thinking about what new combination of electrical apparatus will best suit this newcomer. It is the purpose of this paper to discuss the relative costs of supplying d-c versus a-c power to mining equipment with particular reference to continuous miner setups. Assume that a-c power will be delivered to the mine at some high voltage suitable for transmission to the various substation locations. Typical voltage for this purpose is 4000 volts. The problem then is to change the power to some kind of power suitable for driving the motors of mining equipment. For safety and other reasons the voltage to be delivered to the motor terminals must be under 600 volts.

Jan 1, 1950

By R. M. Reynolds

Engitec Impianti, S?.p.A. of Milan, Italy has successfully designed, constructed and has in operation state-of-the-art battery breaker systems at two European locations. A third facility i:s partially completed in Toronto, Ontario, Canada. The CX system crushes whole batteries, separates the various components and desulfurizes the battery paste. The system also produces sodium sulfate from the sulfuric acid and lead sulfate contained in the batteries. Actual plant operating data indicates that the desulfurized paste contains less than 0. 6 percent sulfur and less than 0. 5 percent antimony. The CX system utilizes mechanical screening and an up-flow hydrodynamic separator to accomplish the component separation. Sodiwn hydroxide or sodium carbonate is used for desulfurization. The sodium sulfate brine is evaporated and crystallized to produce clean anhydrous sodium sulfate suitable for use by detergent or glass manufacturers. Plant data also indicates that an increase in furnace productivity of about 25 to 30 percent is achieved using feed from the CX system. The desulfurized paste is very suitable for electrolytic processing as an alternative to pyrometallurqical processing.

Jan 1, 1990

By Min Chen, Lei Xu

Sintering behavior and performance of high alumina refractory based on the ternary subsystem MgAl2O4-CaAl4O7-CaAl12O19 were investigated using ZrO2 as an additive up to 8 wt.% by solid state reaction sintering. It was found that the added ZrO2 could dissolve in the CA6 grains in the form of a solid solution, which enhanced the isotropic growth of CA6 grains and then improved the sintering. As a result, the densification process was improved and areas with enrichment of ZrO2 showed a more compact structure. With further increase of ZrO2 addition, tetragonal ZrO2 were found to locate in the grain boundaries for exceeding the solid solubility limit, which enhanced the thermal shock resistance, indicating that addition of ZrO2 exhibited a positive effect on sintering behavior and performance of this refractory. In addition, it is considered that the optimal amount of ZrO2 addition was about 4% considering the performance together with the cost.

Jan 1, 2015

By F. Dai

Granitic rocks usually exhibit strongly anisotropy due to pre-existing microcracks induced by geologic loadings. The understanding of the rock anisotropy in mechanical properties such as tensile strength is critical to quarrying and stabilization of underground structures. In this paper, Brazilian tests are conducted in combination with MTS material testing machine and split Hopkinson pressure bar (SHPB) system to measure both static and dynamic tensile strength of anisotropic Barre granite. Samples are cored and labeled using the three principle anisotropic directions of Barre granite (BG). These directions are also chosen as the loading directions for the Brazilian discs. For dynamic tests, pulse shaping technique is used to achieve dynamic equilibrium in the samples during the test. Finite Element Method is implemented to formulate equations that relate the failure load to the material tensile strength employing a orthotropic model for Barre granite. For samples in the same orientation group, the tensile strength shows clear loading rate sensitivity. The tensile strengths exhibit clear anisotropy under static loading; while less anisotropy under dynamic loading. The tensile strength anisotropy of Barre granite is interpreted as interactions of the pre-existing microcracks.

May 1, 2009

By AIME AIME

BERYLLIUM is one of the most interesting of the minor metals and distinctly a modern development, for until the last two decades it had practically no commercial importance whatever. Then it was discovered that when small quantities of it were alloyed with copper, a copper alloy of unusual and valuable qualities resulted. This is by far its major use-in the manufacture of strong, heat-treated copper-base alloys in which the beryllium content varies from about 0.3 to 2.5 per cent. Its second most important use, though much smaller, is in the form of oxide or other nonmetallic products in the fluorescent lamp, X-ray, cathode ray, and television industries. Certain beryllium salts have the quality, in common with several other materials, of transforming short-wave radiation and cathode rays to visible radiation. Such materials are commonly known as phosphors, and the beryllium salts are the most important phosphors now in use. The third largest use for beryllium is for ceramics, including refractories. Beryllium is also used in small quantities in the form of the metal itself.

Jan 1, 1943

By Do-Hyeong Kim, Tae-Jung Kim, Seung-Yeon Won, Jong-Jin Pak, Min-Kyu Paek

Liquid iron alloys containing V, Mo, and Ni can be produced by the carbothermic reduction of spent catalysts used in petrochemical industry. Thermodynamics of carbon in these alloy melts is important for refining these alloys. In the present study, the carbon solubility in Fe-V, Fe-Mo, Fe-Ni, Fe-V-Mo, Fe-V-Ni, Fe-Mo-Ni and Fe-V-Mo-Ni alloy melts of various compositions was measured at 1873 K. The temperature dependency of vanadium effect on carbon solubility in liquid iron was also measured in the temperature range from 1823K to 1923K. The additions of vanadium and molybdenum significantly increased the carbon solubility in liquid iron alloys while nickel decreased the solubility. The experimental results were thermodynamically analyzed using Lupis’ relation at constant activity to determine the first- and the second-order interaction parameters of vanadium, nickel and molybdenum on carbon at carbon saturated condition. Using thermodynamic parameters determined in the present study, the carbon solubility in Fe-V-Mo-Ni alloy melts of various composition were accurately predicted and verified experimentally at 1873 K.

Jan 1, 2014

By J. B. Hamilton

The advantages of generating and distributing electrical energy direct from the coal-fields so closely affects the mining industry that a few remarks on the unbalanced phases of coal distribution is worthy of attention. The value of coal imported into Canada from 1912 to 1921 exceeded the sum of $580,000,000. In 1922 Ontario imported 1,640,000 tons of anthracite and 9,440,000 tons of bituminous coal. I submit that the use of Saskatchewan lignite in an electrical super-power plant equipped for the carbonizing of coal, and disposal of excess gases would be the commencement of a solution of the fuel shortage in Ontario. As Saskatchewan becomes more and more populated and manufacturing increases, the amount of by-product carbonized fuel available for shipment to Ontario will increase, and its shipment to that province would decrease the trade deficit of the national balance sheet. If and when this is carried out it will mean a better and wider market for Alberta fuels in Saskatchewan and Manitoba.

Jan 1, 1924

By H. P. Greenwald

"INTRODUCTION In the course of its studies of the explosibility of various coal dusts in the Experimental coal mine, the Bureau of Mines has tested coals representing the entire range of volatile content found in the United States. In connection with their work the Bureau's field engineers some¬times meet operating officials who are not impressed by the fact that there is an explosion hazard in mines working low—volatile coals. Actually the difference in explosion hazard between high—volatile and low—volatile coals is one of degree and not of kind. The purpose of this paper is to set forth briefly the experimental evidence that has been accumulated on the explosibility of coal dusts containing 8 to 31 percent volatile matter on a dry, mineral—matter—free basis.There have been numerous dust explosions in mines in which coals were worked that have compositions within this range. Those explosions are listed in an appendix, together with a bibliography of Bureau of Mines papers describing explosion tests in the Experimental coal mine."

Jan 1, 1940

By John N. Cunningham

Despite the wide use of micropiles for rehabilitating and retrofitting existing structures, little is known regarding the load-transfer distribution of grouted micropiles in various soil deposits. The rehabilitation of a concrete-frame warehouse in Portland, Oregon, required provisions for the seismic restraint of a new shear wall; the installation of two micropiles was specified to meet project requirements. The micropiles were uncased, 19-m (63-ft) long, 200-mm (8-in) nominal diameter, and reinforced full-length with a 64-mm (No. 20) diameter hardened steel threadbar. Due to space limitations, a sacrificial, instrumented micropile was installed near the two production piles to verify design assumptions. This paper describes the geologic setting of the project within the unsaturated Missoula Flood deposits, instrumentation, load-displacement behavior, load transfer, and Beta-coefficients for the sacrificial micropile.

Jan 1, 2011

By D. Moradkhani

The heap leaching of oxide copper ores with copper cathode recovery by solvent extraction and electrowinning is now well established as a low-cost method of copper recovery. The main purpose of this study was to extract copper from the copper low-grade oxide ore of Chodarchaei mine using column leaching. The copper oxide ore contained 1.1% Cu and 1.75% Fe. The mineralogical analysis indicated the malachite (Cu2(OH)2CO3) was mainly composed of oxidized phases. The sulfuric acid leaching experiments were performed under the laboratory conditions. The influence of several parameters on the course of the reaction such as particle size, acid concentration, flow rate, and time was examined. The optimum collective extraction of copper and iron was obtained at a particle size of +10-15 mm for a leaching duration of 3 days with sulfuric acid concentration of 100 gpl and using a flow rate of 2.5 cc/min. Under these conditions, the recovery of copper and iron were 98.54% and 41.99%, respectively. Keywords: column leaching, copper, iron, working diagram.

Sep 1, 2012

By Sadtler, C. B.

IT is generally assumed that in most metals and alloys a given tensile stress produces a given deformation irrespective of the length of time during which the stress is applied. This assumption is justified in most of the important engineering applications of metallic materials; however, in the case of some metals and alloys used or tested at temperatures over or slightly under that at which recrystallization can occur the assumption is not warranted.1 This paper deals with the variations of deformation produced by a constant tensile stress acting for varied lengths of time in the special case of thin aluminum alloy sheet of the duralumin type, which had been subjected to different thermal and mechanical treatments. The material investigated was in the form of a sheet approximately 0.002 in. thick, which had been cold-rolled from a thickness of 0.020 in. It has been found that at a sufficiently high constant tension such material deforms continuously with the elapse of time and that the rate at which this deformation occurs is greatly influenced by the previous thermal and mechanical treatments.

Jan 1, 1927

By CHARLES M. SCHWAB

THE ENGINEERS have placed this great country of ours in a preeminent position with everything pertaining to manufacture, metallurgy, and the kindred arts. We are second to none in the world. We have a country which, another speaker has said, God has endowed with such riches in coal and natural resources as no other country in the world. But rich as these are, there is one thing greater; the sturdy character, energy, and integrity of its people, which will make these great resources an influence in the world's developments. Great as are these resources and the energy and integrity of our people, there is one problem of our .engineering, which I term human engineering, that is of far more importance than the creation of machines and methods, with which you have been so successful in the past. Of what value is the skillfully devised machinery, the complex process, unless manned and operated by people whose heart and soul are in sympathy with the work they are doing and who have before them the giving of a complete day's work for a day's pay?

Jan 1, 1920

By Tom Gonzales

At San Manuel, AZ, Magma Metals Co. operates an Outokumpu flash furnace, four Peirce-Smith converters and two anode casting wheels that are supported by six anode vessels. Process gasses from the flash furnace and converters are treated in a two-train/ double-contact sulfuric acid plant. The plant captures 98% of the sulfur. A new flash furnace was commissioned in July 1988. It has since processed more than 2.7 Mt (3 million st) of sulfide concentrate without a major rebuild. The company has gained unique experience in the operation of the flash furnace at high oxygen enrichments with low off-gas dust loadings. New procedures have been developed to maintain secondary material generation at equilibrium and for maintaining metallurgical control of operating parameters. Process flow description At Magma's San Manuel plant, concentrates and other copper-bearing material are blended and conveyed from two separate areas of the plant to three 420 t (465 st) capacity wet charge bins located above the rotary dryer. Flash furnace silica flux is conveyed to a 227-t (250-st) capacity fine flux bin located adjacent to the wet charge bins. The concentrate and flux are blended in controlled amounts and fed into a 168-t/ h (185-stph) gas-fired rotary dryer. The wet charge enters the dryer at 8% moisture and is dried to 0.2% moisture. The dried charge is pneumatically conveyed to a 580-t/h (640-stph) dry charge bin located above the flash furnace. Flash furnace charge is drawn from the bin by two drag conveyors at a concentrate feed rate of 145 t/h (160 stph). The charge is mixed with enriched combustion air and injected into the furnace reaction shaft. In the reaction shaft, the charge is oxidized to form matte, slag and a rich SO, off-gas.

Jan 1, 1992