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By L. T. Loe, A. S. Norsk, Mo i. Rana

High production rate and good stability demand the optimization of all phases of electric pig iron smelting. This is important with respect to slag chemistry, which to a large extent regulates the process temperature in electric smelting. Controlled basicity and slag volume. and a satisfactory screen analysis of the reduction material and sinter, are of the utmost importance for smooth furnace operation. Large variations in slag volume and in B/ A and C/Fe ratio will have an influence on the furnace resistance and thus the specific energy development in the furnace, which lead to variable reduction of SiO.. The result will be variable hot -metal quality and un-stable furnace operation.

Jan 1, 1970

By Bill Linville

During calendar year 1972, the Bureau of Mines was engaged in some 20 major areas of research for the development of new and improved efficient methods of conservation and utilization for petroleum and natural gas, oil shale, and coal. Made up of numerous projects described in this report, the program was carried out through research performed at research centers and laboratories in the field supervised and supported by administrative personnel of this Bureau of the Department of the Interior. Based un this research, 186 technical reports were published by the Bureau or others, and numerous other reports were prepared for Federal agencies, State agencies, and organizations engaged in cooperative research programs with the Bureau.

Jan 1, 1973

By G. R. Harrod

Effective mine operation demands that the right people have the right information at the right time. Caterpillar's Mining and Earthmoving Technology System (METS) meets this demand by providing "real-time" information transfer between the mine offices and machines equipped with the Caterpillar Computer Aided Earthmoving System (CAES). Transfers of mine plans from the mine planning software to CAES-equipped machines give operators access to current mine plans within minutes of their creation. Additionally, office personnel have access to a current digital terrain model (DTM) of the mine site as it is updated in "real-time" by CAES-equipped machines. METS provides mine personnel in operations, planning, and management the information they need when they need it.

Jan 1, 1998

What is a conflict, as it is understood by men of the extractive industries? And what are the circumstances out of which these conflicts arise? A start can be made with the notion of economic conflict, which can be defined as rivalry over the use of economic resources. Such rivalry is a central part of all economizing activity. It is present within the individual, within the family, and within the business firm. In each of these units there are multiple goals competing for use of a limited income. And economic rivalry is present among individuals and firms who are competing with one another for use of the limited quantity of economic resources available to us as a society.

Jan 7, 1961

By J. A. Drozdiak

In this paper we examine, through pilot-scale testing, the possibility of operating a circuit comprised of two stages of HPGR comminution, followed by grinding through a horizontal stirred mill. In order to assess whether the novel circuit design could achieve the reduced energy requirements indicated in the literature, two more-established circuits, a cone crusher / ball mill and an HPGR / ball mill, were examined using a combination of testing and flowsheet simulation. The results showed that, based solely on the specific energy requirements for comminution, the HPGR / stirred mill circuit achieved a reduction of 9.2% and 16.7% over the HPGR / ball mill and cone crusher / ball mill circuits, respectively.

Jan 1, 2012

By Donald C. Strimbeck

The Bureau of Mines, U.S. Department of the Interior, is conducting research and development on a coal-burning gas turbine. This work includes the development of (1) turbine blades resistant to coal ash erosion, (2) equipment to feed coal under pressure to a turbine, (3) an efficient combustion system, and (4) equipment to remove coal ash from the gases that drive the turbine. Initial emphasis is being placed on testing the first turbine ever equipped with blades designed specifically for use with coal as the fuel. Operating tests with this turbine are now in progress. This paper describes the Bureau's coal-burning gas turbine development program and progress on this operating test.

Jan 1, 1964

By B. G. White

Traditional interpretations of vein ore deposits in the Coeur d' Alene Mining District, such as the view that these deposits formed in a transcurrent tectonic regime during the Precambrian, are being supplanted by the view that the deposits (1) formed in low-grade metamorphic shear zones similar to those that host an important type of gold deposit, (2) display features, such as wall rock carbonate zoning and vein zoning, that are common to ore deposits elsewhere, and (3) are probably Mesozoic and possibly related to emplacement of the Idaho batholith. In recent years, new interpretations have led to major ore discoveries that are likely to extend the life of the district for decades.

Jan 1, 1998

By AIME AIME

I am happy to welcome you to the twenty-third conference of the National Open-Hearth Committee, and our joint conference with the Blast Furnace Committee, of the American Institute of Mining and Metallurgical Engineers. It is appropriate that, for our fifteenth year anniversary, we should meet in the hotel and the city where this Open-Hearth Committee was inaugurated in 1925. At that first meeting, only a handful of men from a number of steel companies met to discuss ways and means to start a movement to improve the practical and metallurgical technique of open-hearth operations among independent manufacturers, as the United States Steel Corporation had carried on for many years.

Jan 1, 1940

By J. P. Powell

Since the beginning of waterflooding in the Midcontinent area, the Bureau of Mines has published many reports3-6/ describing in detail the results obtained on individual waterflooding projects in the area. These are intended as guides for operators in the selection of well-spacing, water-treating, and other techniques, as well as an indication of the results being obtained in waterflooding in various areas, fields, and horizons. In addition, Bureau personnel has arranged a tour of selected waterflooding projects each year for the past several years so that actual operating conditions may be observed and an additional opportunity provided for exchanging information. Each of these tours has been supplemented by a published

Jan 1, 1959

By J. H. E. Jeffes, K. T. Jacob

Solid oxide galvanic cells, of the type: Pt,Ni-NiO | Solid electrolyte | O(metal),Cermet,Pt, were used to measure the activity coefficient of oxygen in liquid Cu at 1 100 and 1 300°C and in Pb at 1 100°C. Similar cells were used to study the activity coefficient of oxygen in the whole range of Cu + Pb alloys at 1 100°C and in Pb-rich alloys at 900 and 750°C. The results obtained are discussed in terms of proposed solution models. An equation based on the formation of 'species' of the form M(2)O in solutions of oxygen in binary alloys is shown to fit the experimental data

Dec 1, 1971

By B. R. Arvidson

Sharper separation and improved control of the top size increases the fine particle product yield. As the milling circuit recycle stream is reduced, the overall capacity is increased. In some cases, a doubling of throughput is realized, although 25 to 30% increase is more typical. Alternatively, the energy demand may be reduced, although the best economic improvement results from higher capacity. A comparison with a high-pressure roller mill circuit shows that an optimized ball mill circuit retrofitted with the new air classifier has lower energy consumption. The new air classifier features low energy demand and substantially lower maintenance compared to similar equipment. Design and operation of this recently patented classifier are discussed. Several industrial installations will be described.

Jan 1, 1999

By R. W. Huber

The successful development of a titanium prototype of the 81-mm. mortar base plate for the Army Ordnance Corps is outlined in this report. Information is presented dealing with forming, forging, and machining, welding and assembly techniques, and design changes relative to this prototype. INTRODUCTION The work of the Federal Bureau of Mines in making ductile titanium available2/ has resulted in the establishment of a new industry. Owing to its strategic importance and the combination of low density and high strength, titanium has received considerable attention as a structural metal. Titanium's favorable strength-to-weight ratio is of particular importance to the Army Ordnance for equipment that is transported by airplane or by foot soldiers.

Jan 1, 1956

By Peter Dietrich, Joseph DeMello, Norbert Fuegenschuh, Kerwin Hirro, Jeff Brandt, Mike Cole

This paper presents a successful case history of the ground improvement efforts and excavation of twenty-three cross passages between twin bore tunnels driven by EPB tunneling machines in Los Angeles, California on Section 1 of the Westside Subway Extension. Unique and complicated ground conditions local to the tunnel alignment include San Pedro sands, siltstone/claystone Fernando Formation, and zones of “asphalt impacted soils.” To provide water cut-off and soil stabilization, jet grouting was performed prior to TBM excavation at the location of many of the cross passages. However, upon investigating the cross passages prior to excavation, the subsurface conditions required additional measures and SEM tools to ensure successful completion of the project.

Jun 13, 2023

By David G. Dixon

A general, unsteady-state model for leaching of one or more solid reactant species from a non- reactive, porous, spherical pellet is derived in dimensionless form for the interpretation of leaching data, and for use in the design of coarse-ore leaching processes. The effects of diffusion rate, chemical reaction rate, variable reaction order, and competition between multiple solid reactants are examined using the concept of the effectiveness factor. It is shown that the model is capable of simulating both "reaction-zone" and "heterogeneous" kinetics, depending on the choice of three dimensionless parameters. Results of batch leaching tests of artificial ore pellets are presented, and their relationship to the model is discussed.

Jan 1, 1993

By Yogeshwar Sahai

Submerged gas injection into melts contained in furnaces, ladles, or similar transfer vessels is commonly used in industrial practice. In this review paper, conditions leading to gas bubble formation at the nozzle are first summarized. The increasing gas injection rates and other conditions, such as nozzle size, lead to regimes which are commonly known as "bubbling" and "jetting". These are explained. The gas/melt interactions result in energy transfer to the melt. In recent years, a large number of researchers have investigated the relationships between the energy density and the mixing times. Their work is reviewed, and the mixing mechanisms is described. Finally, computational approaches of modeling submerged gas injection are briefly presented.

Jan 1, 1993

By C. I. Basilio

The adsorption of dialkyl di-and mono-thio-phosphinates on gold, silver and gold-silver alloys has been studied in the present work. These reagents, which are selective collectors for sulfide flotation, have been found to improve precious metals recovery from ores. Voltammetric studies have indicated that dithiophosphinate adsorbs on gold at much higher potentials than on silver, while monothiophosphinate adsorbs only on silver. However, both adsorb on gold-silver alloys with the adsorption potential decreasing with increasing silver content. Using FTIR spectroscopic measurements, the surface species formed during the interactions of these collectors have been identified. The results of the electrochemical and spectroscopic measurements have been compared with the contact angle data obtained at controlled potential conditions.

Jan 1, 1992

By A. K. Croteau

"At Craigmont Mines Limited, Merritt, B.C., the mining practice of trackless sub-level caving was started in the latter part of 1966. This type of mining was new to the mine personnel and the mining industry of Canada as a whole. Sub-level caving has presented many old and a number of new problems in maintaining the equipment used in this method. This paper will deal with some of these problems as they affect this particular mining operation. It will be impossible to review all phases of the equipment, but an attempt will be made to cover the most pertinent aspects in maintaining the drilling, mucking and hauling, and auxiliary equipment."

Jan 1, 1970

By Robert S. Williams

NO new ferrous alloys have been produced in the last five or six years that are as outstanding contributions to civilization as were the high-speed steels of the early part of the century or the stainless steels announced at the close of the World War. There have been, however, many developments of major importance having to do either with modifications of existing alloys or with new methods of treatment of older iron or steel alloys. Only a limited number of these new developments can be discussed and their selection does not necessarily imply that these are the most important but merely that they are of general interest rather than perhaps of greater importance in highly specialized fields.

Jan 1, 1939

By Vianey Garcia-Osorio

One of the problems in the carbothermic aluminum process is the substantial loss of aluminum compounds as vapors due to the high temperatures in the process. In order to solve this problem a Vapor Recovery Unit (VRU) is proposed. In this unit operation the aluminum vapor undergoes a series of heterogeneous non-catalytic reactions forming solid, liquid and gas products. In this work a model for the simulation of this unit was developed which includes heat and material balances as well as heterogeneous non-catalytic reactions. The model leads to a system of differential equations; its solution was implemented in Matlab giving as a result a stage-by- stage solid-fluid reaction model.

Jan 1, 2001

By Brendan Demich, Linda L. Chasko, Brendan Macdonald, Timothy J. Orr, Jessie J. Mechling, Cassandra Hoebbel, Jason Navoyski, William Helfrich, Jessica Cohen, Paul E. Schmidt, Jennica L. Bellanca

The National Institute for Occupational Safety and Health (NIOSH) in partnership with the Mine Safety and Health Administration (MSHA) developed VR Mine Rescue Training (VR-MRT). It is a training platform that allows mine rescue team members to explore virtual emergency scenarios collaboratively. Team members use a head-mounted display to visualize and interact together with equipment, hazards, and dynamic ventilation. All player actions are recorded and displayed for debriefing. Researchers at NIOSH demonstrated the training platform at various mine rescue competitions, including the International Mine Rescue Competition, and collected feedback. Participants’ responses were overwhelmingly positive. This paper describes the development of the software platform and the results of the usability surveys and interviews.

Jun 25, 2023