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By R. S. Celmer

The distributions of cobalt, molybdenum, copper, and selenium between nickel matte and silica-saturated iron silicate slag have been determined in the region of the metallic saturation boundary, at 1523 K. Results are given as a function of the composition of the coexisting Fe-Ni alloy and the activity of iron in the system. Under strongly reducing conditions, these minor elements display a marked preferential accumulation in the sulphide phase. It is shown that the dissolution of cobalt and molybdenum in slag follows an oxidative mechanism, and distribution equilibria are correlated with the oxygen potential. From these data, the thermodynamic properties of cobalt in nickel matte are computed. Further, comparisons of minor element partitions are made between the nickel and copper matte smelting cases under metal saturation conditions.

Jan 1, 1988

By Douglas A. Donato

This Information Circular presents the MULSIM/PC system of numerical modeling computer programs developed by the U.S. Bureau of Mines. This system consists of four programs: PREMUL, the preprocessor or mesh generator; MULSIM/PC, the actual numerical modeling program (number cruncher); MUL3D, a three-dimensional postprocessor; and MUL2D, a two-dimensional postprocessor. These programs were specifically designed to operate on IBM-compatible (MS-DOS-based) personal computers for easy transfer of this technology to the mining industry and academia. MULSIM/PC uses a subvariation of the boundary-element method, namely, the displacement-discontinuity technique, for linear-elastic geomechanical analysis of mine plans in one or two parallel underground tabular deposits. Results calculated by this technique include stresses and displacements as they relate to changing mine geometries and materials. In addition to describing the MULSIM/PC program and its features, and providing a detailed example model, this report also documents the associated preprocessing and postprocessing programs that are part of the MULSIM/PC system. User's guides for all the programs are contained in the appendixes following the main report.

Jan 1, 1992

By P. Soupios

Seismic geophysical methods have long been used by geologists and geophysicists to delineate subsurface features. These techniques work because different types and strengths of soil and rock transmit energy at different velocities. The Crosshole-Downhole tests (CH-DH) and seismic refraction survey (RS) are among the most used methods in engineering applications to obtain the elastic properties of subsurface layers. As a result, seismic methods have evolved into a cost-effective tool for rapidly determining depth to bedrock in engineering and construction projects. The seismic methods are best suited to sediment thickness analysis, bedrock quality determination and detection of the presence of weaknesses in the bedrock before the erection of any civil engineering structures such as bridges, tunnels, dams and portals. Seismic methods are also useful in estimating the rippability of bedrock ahead of construction. These methods are particularly useful for large-scale projects that require a significant number of drill holes, resulting in a substantial investment of time and costs for drilling. The CH-DH and RS methods are typically comparable in total cost to drilling, but provide significantly more information in 2-D and 3-D and therefore reduce the likelihood of conceptually oversimplifying the subsurface conditions. The above mentioned methodologies were considered to be the most appropriate geophysical methods for investigating the shallow structure and the dynamic soil properties of the area where the Ilarionas Dam is scheduled to be constructed. The main target of this work was to prove the potential of geophysical methods in providing accurate information to the civil engineer and to obtain information on the dynamic soil and rock properties for earthquake design analyses for the dam construction. Specifically, nine refraction seismic profiles and three cross-hole-downhole seismic tests were implemented to determine the subsurface conditions of the study area. The tests determined the shear and compression wave velocity profiles versus depth and other crucial parameters such as Young and Rigidity modules. Furthermore, they allowed the detailed 2-D mapping (along several profiles of the study area) of the subsurface variation of the soil and rock dynamic moduli.

Jan 1, 2006

By L. Alan Weakly

At a time when the US mining industry is struggling to emerge from a lengthy recession, the burden of new, unnecessary regulations could shorten the life of, or be fatal to many domestic mining companies. The possibility of new restrictions on the use of diesel equipment operating in underground mines is one example of unnecessary regulations. These could cause serious harm to the economic health of many mining companies. Whether future health-related Mine Safety and Health Administration (MSHA) regulations restricting the use of diesel equipment are unnecessary, depends on whether these restrictions are supported by fact or created in a political environment. The mining industry has benefited from the use of diesel equipment in underground metal-non-metal and coal mines for more than 50 years. Since first introduce to underground mines in the early 1940s, the use of diesel equipment has grown in numbers and size. During this time, the mining industry in America has achieved much higher productivity rates and improved safety. Although all these gains cannot be attributed to the greater use of diesel equipment, a high percentage can be. I began my professional mining ca¬reer in 1970 working in the Missouri lead mines. At that time, the use of diesel equipment was well established in metal-non-metal mines throughout the United States and many parts of the world. As director of mining research for St. Joe Minerals Corp. (now The Doe Run Co.), I was involved in research to improve mining productivity and safety. This involved investigating the better and safer use of existing or new mining methods, products, equipment and people. Within this group, diesel equipment had the single largest positive impact.

Jan 1, 1993

By AIME AIME

The following persons have been proposed for election as members or associates of the Institute during the period, March 16 to May 1, 1907. Their names are published for the information of members and associates, from whom the Committee on Membership earnestly invites confidential communications, favorable or unfavorable, concerning these candidates. A sufficient period (varying in the discretion of the Committee, according to the residence of the candidate) will be allowed for the reception of such communications, before any action upon these names by the Committee. After the lapse of this period, the Committee will recommend action by the Council, which has the power of final election. The names of candidates were formerly published in the various circulars of the Institute, issued from time to time to the members. Hereafter, they will appear regularly in the Bi-Monthly Bulletin, each number of which will contain the names received since the issue of the preceding Bulletin.

May 1, 1907

By Sarah Bélair, Denis Beltrami, Valérie Weigel

"Mabounié is a polymetallic deposit in Gabon containing niobium (1.2%), tantalum (0.03%), rare earth elements (REE) (1.4%) and uranium (0.03%) that are mostly carried by Pyrochlore minerals. Classical route for niobium recovery is a pyrometallurgical process that consists in pyrochlore flotation, dephosphorization of the niobium concentrate and aluminothermy to obtain ferro-niobium. Pyrochlore concentrates can also be treated by a hydrometallurgical process with a mixture of sulfuric and hydrofluoric acid leaching followed by solvent extraction to separate niobium and tantalum. However, the first process does not allow recovering REE and the second one is not environmentally friendly because of the use of HF.ERAMET is looking for new opportunities on strategic metals market and has recently developed a hydrometallurgical process for the recovery of all these metals based on a sulfuric acid treatment of the ore. After solubilisation of the valuable elements, niobium / tantalum are precipitated as a concentrate (12% w/w Nb and 0.3% w/w Ta) while REE (2.7 g L-1) and uranium (90 mg L-1) remain in solution. Nearly 90% of REE are recovered from the solution by conventional REE double salt precipitation [NaREE(SO4)2.xH2O) method but some REE still remain in solution as this method does not allow to quantitatively recover medium (Sm, Eu, Gd, Tb, Dy) and heavy (Ho, Er, Tm, Yb, Lu, Y) rare earth elements. From the different process routes studied (solvent extraction, precipitation, ionic exchange etc.), an innovative method has been developed and patented to recover REE residual concentration in solution. This is based on an aluminum removal step followed by precipitation of REE as REE phosphate concentrate (REEPO4) by phosphate addition into solution. The phosphate concentrate is then purified according to the conventional monazite treatment, i.e. caustic conversion and REE solubilisation in acidic media."

Jan 1, 2016

By G. W. Cullen

Niobium-tin has been prepared on insulating suhstrates hby simultaneous hydrogen reduction of gaseous niobium and tin halides. Stoichiometric material is greater than 98.8pct theoretical density, appears to he single-phase, and has a total impirity level less than 0.3 at. pct. Transition temperatures and lattice constants may he related to composition. Typical current densities in various fields and orientations are given. IT is known that Nb3Sn carries large current densities in high fields, 1 and exhibits an unusually high transition temperature2 and critical field.3 For these reasons high-field solenoids have been constructed of this material.4 Because of the emphasis on solenoid fabrication, much of the materials research has been directed toward development of wire geometries wherein the brittle Nb3Sn is supported by a more malleable metal or alloy. There are, however, basic studies and applications that can be carried out only on Nb3Sn supported by an insulator. Insulating substrates are desirable for a number of reasons: the substrate does not interact with applied or induced currents and fields; diffusion of metallic species into the de- posit is avoided, both during the preparation and during subsequent heat treatment; irradiated samples are not more active than the deposit itself. Unsupported Nb3Sn geometries may also be prepared by preferential chemical dissolution of the insulating substrate. This report describes the preparation and properties of Nb3Sn deposits on ceramic substrates. Experiments currently utilizing material prepared in the manner described in this report include the following: dependence of current-carrying properties on field strength and orientation 5,6 radiation damage,7,8 tunneling,9 thermal conductivity (substrate removed),1° microwave surface impedance," tube magnetization,6,12 resistivity as a function of temperature,13 and current density and transition temperature as a function of annealing.14 Possible practical applications include magnetic shielding, superconductor generators, and frictionless bearings. PREPARATION Methods for the deposition of elemental niobium and tin by hydrogen reduction of the gaseous metal halides have been known for some time,15,18 but only recently a procedure was developed in this laboratory17 for the codeposition of these two metals on a hotwire as the intermetallic compound, Nb3Sn. This method of simultaneous hydrogen reduction of the gaseous niobium and tin chlorides is used for the preparation of Nb3Sn On ceramic substrates. The procedure differs from that employed on a hot wire in that insulating substrates cannot conveniently be heated to temperatures greater than their surround-

Jan 1, 1964

Process variables in flotation circuits are outlined with a view to producing mathematical models of circuits. The nature of the kinetics of flotation are discussed and the effect of process variables on the kinetics considered. An approach for a possible model is briefly outlined.

Jan 1, 1971

By Larry Kaufman, Morris Cohen

THE solid phase equilibria' and the martensitic transformation in the iron-nickel system have been the subject of considerable study. In addition, there have been numerous investigations on the calorimetric and thermodynamic properties of iron-nickel alloys. The purpose of the present work is to extend the existing information concerning the martensitic reaction in the iron-nickel system, and to develop a general thermodynamic treatment which will encompass the equilibrium and non-equilibrium phase

Jan 1, 1957

By E. C. Reed

Oil was discovered in Nebraska on Nov. I, 1939, when the Pawnee Royalty Company's Boice No. I well, about 3 miles west of Falls City (NE 1/4 NE 1/4, sec. 18, T.r N., R.16 E., Richardson County) was drilled into the Hunton formation but the develop-ment of the area took place during 1940. After a pumping test lasting 18 days, the Boice well stopped producing and failed to qualify for the State bonus of $ 15,000 offered for the first oil well to produce go bbl. per day for 60 consecutive days. On May 9, 1940, the Pawnee Royalty Company's Bucholz No. I well was completed about M mile southeast of the discovery well and flowed at the rate of about 330 bbl. per day, easily meeting the State bonus requirements. In addition to the discovery well, which later was reconditioned, and the bonus well, 28 producers were drilled in the Falls City field during 1940. Of these wells, 23 are in sec. 20, two are in the northern part 'of sec. 29, two in the southwestern part of sec. 17 and three in the eastern part of sec.

Jan 1, 1941

By E. C. Reed

Oil was discovered in Nebraska on Nov. I, 1939, when the Pawnee Royalty Company's Boice No. I well, about 3 miles west of Falls City (NE 1/4 NE 1/4, sec. 18, T.r N., R.16 E., Richardson County) was drilled into the Hunton formation but the develop-ment of the area took place during 1940. After a pumping test lasting 18 days, the Boice well stopped producing and failed to qualify for the State bonus of $ 15,000 offered for the first oil well to produce go bbl. per day for 60 consecutive days. On May 9, 1940, the Pawnee Royalty Company's Bucholz No. I well was completed about M mile southeast of the discovery well and flowed at the rate of about 330 bbl. per day, easily meeting the State bonus requirements. In addition to the discovery well, which later was reconditioned, and the bonus well, 28 producers were drilled in the Falls City field during 1940. Of these wells, 23 are in sec. 20, two are in the northern part 'of sec. 29, two in the southwestern part of sec. 17 and three in the eastern part of sec.

Jan 1, 1941

By AIME AIME

Air transport supplants the old methods. The 3-piece canoe fits in the plane and likewise makes possible not a bad division of labor over a 5-mile portage

Jan 1, 1933

By James T. Bartis

Review of Key Issues Affecting the Prospects of CTL in the United States ?Issues of concern to the public - Impacts of coal mining - Water use - Greenhouse gas emissions ?Issues of concern to investors - CTL production costs - Oil prices - How greenhouse gas emissions will be managed ?RAND recommendations

Jan 1, 2009

By J. S. Kennedy, A. A. Lerew, C. M. Judson, G. L. Simard

DITHIOPHOSPHATE collectors are commonly used in the flotation of sulphide minerals. Studies of the interaction of a typical dithiophosphate collector with galena surfaces have been previously reported from. these laboratories." These fundamental studies were carried out by employing phosphorus labeled radioactive dithiophosphate. Radioactivity determinations then could be used to measure readily and accurately the small concentrations of dithiophosphate that, are present under conditions of flotation processes. Measurements were made on ground mineral, determining the amount sorbed indirectly from the concentrations in solution; and studies were also made with single crystals, determining the amount sorbed directly by counting the crystal surface. The rates, isotherms and reversibility characteristics of dithiophosphate sorption, the competition between phosphate and dithiophosphate for the mineral surface, and the exchange of sorbed dithiophosphate with dissolved dithiophosphate were studied. These studies have now been extended by sorption measurements in flotations with a Fagergren, machine. For this work, the selective flotation of galena and sphalerite from quartz was chosen, using ammonium di-(sec-butyl) dithiophosphate as. the collector, sodium cyanide as depressant for sphalerite, and copper sulphate as an activator for sphalerite. While the selective flotation of galena and sphalerite using a single dithiophosphate collector is not typical of flotation practice (two different collectors are generally used), it was found that a reasonably good separation could be obtained by using zinc sulphate with the sodium cyanide in the galena flotation and by cleaning the sphalerite concentrate or by carrying out the sphalerite. flotation in an alkaline medium. Data of practical importance on the distribution of collector between the concentrates, tailings, and solutions were obtained, particularly with regard to the effect of copper sulphate and sodium cyanide. In addition to the. selective flotation of galena and sphalerite from quartz, single flotations of galena-quartz and sphalerite-quartz mixtures were carried out, along with blank flotations on quartz alone. The present paper describes the results of these experiments. As in previous papers, the term sorption is used to designate uptake of collector by the mineral, without implication as to the nature of the processes involved. Experimental Materials: The mineral system was a ground synthetic mixture of galena, sphalerite, and quartz. The galena was from Galena, Kans., and contained 75 pct lead (theoretical 85.6 pct Pb for PbS); the sphalerite, from Ottowa County, Okla., contained 63 pct zinc (theoretical 67.2 pet Zn for ZnS) ; and the quartz from Klondike, Mo., analyzed as 99.97 pet SiO2. Sulphur labeled radioactive di-(sec-butyl) dithiophosphate was prepared from S82 supplied by the Oak Ridge National Laboratory on allocation from the U. S. Atomic Energy Commission. The synthesis consisted of precipitating barium sulphate, reducing the barium sulphate to barium sulphide, acidifying to form hydrogen sulphide, and oxidizing the hydrogen sulphide with iodine to elemental sulphur.

Jan 1, 1952

By Bennett D. Lass

A new method for determination of residual flotation oils on beneficiated kaolin clays has been developed. The method, which yields qualitative information, is based on fluorescence measurements employing a spatially resolved, polychromatic illumination source for excitation, and a two-dimensional detection scheme using a silicon-intensified, video imaging device. The method was used to identify residual oils on a beneficiated, Washington County, Georgia, crude clay. The results were compared to a similar qualitative analysis performed via capillary column gas chromatography using an FID detector. The video fluorometry was the preferred method of, analysis.

Jan 1, 1983

By Todd Minoski, Matthew McElhinney, Mark Morris, Mark Mazzella, Joseph Bright, Morgan Sears, Craig Compton

To promote the safety and health of U.S. mineworkers, researchers with the National Institute for Occupational Safety and Health (NIOSH) are currently involved in gathering additional field data from the nation’s underground coal mines. The purpose of this field study was to monitor ground movement and changes in pressure during mining where conditions include a thick parting in the coal seam. To accomplish this, three arrays of field instrumentation were installed in the wraparound bleeder of a room-and-pillar panel at the Maple Eagle mine located in southern West Virginia. Borehole pressure cells (BPCs) were used to monitor the change in pressure in pillars located adjacent to the gob. Roof extensometers were installed to measure roof sag at various horizons in the immediate roof, while rib extensometers were installed to measure displacement of the in-seam parting as mining progressed. Additionally, visual observations and manual measurements were taken during subsequent site visits. The repeatability of results, important from a scientific perspective, was accomplished by successfully obtaining field measurements from two nearly identical instrumentation sites. The data collected indicated that the front abutment extent at the edge of the panel was approximately 200 ft, corresponding to a distance of 9– 10 times the square root of the depth. Yielding of the slabbed pillar began when the pillar line was approximately 290 ft outby the instrumentation sites. This was followed by load shedding onto the abutments and the measurement of small amounts of roof sag in the No. 1 entry. Instrumentation data, as presented in this paper, can be used to better understand stress redistribution, pillar performance, and roof/rib displacements. Additionally, this data is suitable for assisting in the calibration of numerical models. Insight gained from applying these models can be used to make better engineering-based judgments for conditions that could potentially be encountered in the future.

Jul 1, 2023

By U JSger

The Westerschelde tunnel will be the first permanent road link between the Dutch regions of South Beveland and South Flanders. Two tunnel tubes, each 6.6 km long, will be driven using the shield tunnelling method. The difficult ground conditions and a water pressure of up to 6.5 bar make great demands on the design. This paper describes the problems and their solutions.

Jan 1, 1999

By Paul Kennedy, Daniel R. McConnell, Ruth Price

"The underwater search for the passenger aircraft MH 370 produced rare high resolution datasets of the ocean floor of extraordinary size and detail. The survey design and operations were for sole purpose of finding the aircraft debris field. The aircraft was not found in the detailed search area and the survey was suspended. As planned, the data are now being made available to scientists and researchers. The large survey area includes geologic settings that might be prospective for seafloor minerals. A review of the data can provide insights to seafloor mineral prospectivity in the Southern Indian Ocean and is a large dataset that can be used to calibrate object detection for the design of dedicated mineral exploration surveys.Economic minerals in the Southern Indian OceanOceanographic research and scientific drilling cruises have assembled geologic and geophysical data points in the Southern Indian Ocean. These, together with satellite derived bathymetry and gravimetric data, earthquake mapping, and mapping of magnetic anomalies have, even if they lack detail, produced a general understanding of the main tectonic features and plate movements in the Southern Indian Ocean as well as contributed some marine mineral data.The Southeast Indian Ocean Manganese Pavement, a large manganese nodule field south of Diamantina Fracture Zone was discovered in 1970. Dredging and photographic data from the discovery cruise determined that dense nodule accumulations cover 900,000 sq. km."

Jan 1, 2017

By D. F. Cater

The Macassa Mine is a mature mine with a 61 year history of continuous production. The majority of past production has been derived from a zone called the '04 Break (Main Break). Recent underground mine exploration has been successful in locating several neighbouring ninera1ized zones. This paper will characterize the spatial location, geometry and mineralogical properties of these secondary zones. Future plans for underground mine exploration to follow-up on these target zones will be outlined.

Jan 1, 1995

By Arnold R. Pasieka, George V. Sotirow

"The object of this paper is to outline a computerized net cash flow approach for practical cutoff grade determinations. A cutoff grade carries not only geological but also economic value, in which costs are balanced against revenues. For different situations, cutoff grades are a 'standard of value' that are determined for the purpose of classifying economic or uneconomic mineral reserves in a specified time frame. In a constantly changing technical and economic environment, the decision to develop or maintain a mining operation at its best economic potential, requires an appropriate cutoff grade strategy, a strategy consistent with short- and long-term operational and corporate objectives and one based on realistic marketing and metal prices forecasts. The use of a project evaluation computer program, in combination with specific corporate net cash flow requirements, shows the most promising and flexible team approach for cutoff grade optimization.IntroductionThe recent recession has had a devastating effect on the Canadian mining industry. Exploration and mining R&D expenditures have been critically reduced and now are believed to be below healthy levels. Ore reserves, mine life and cutoff grades are careening in several directions because of low base metal prices, relatively high costs and sensitive precious metal prices.These conditions demand an improved understanding of the terms ""ore"" and ""cutoff grades"" as they are applied to the planning process and day-to-day operations. ""Ore"" or 'ore reserves"" is a dynamic concept, reflecting a cumulative effect of changes in geological, technical and economic conditions in terms of material which can be mined at a potential profit. By contrast, if economics are not the primary consideration, the term ""mineral reserve"" or ""mineral inventory"" should be used to describe the mineral deposit. For different situations, cutoff grade is ""a standard of value"" determined for the purpose of classifying mineral reserves as economic or uneconomic in a specified time frame. The question of mining at average reserve grade or low-grade material during high metal prices is of paramount importance for cutoff grade strategy."

Jan 1, 1985