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By Batric Pesic

Solvent extraction of nickel and cobalt from the real leach solutions was studied by using a novel extraction system. The extraction system was a mixture of 2,6-bis-[5-n-nonylpyrazol-3¬y]] pyridine (BNPP) and dinonylnaphthalene sulfonic acid (DNSSA). The BNPP represents a novel molecule, which was designed and synthesized in our laboratory. Real solutions for the study were prepared by leaching of two different cobalt-nickel bearing concentrates, cobaltite [CoAsS] concentrate from Blackbird Mine, Idaho, and siegenite [(Ni,Co)3S4] concentrate from Missouri Lead-Belt. The major strength of the system was the selectivity of extraction toward nickel and cobalt from iron containing solutions. Other metals such as Mn, Mg, Ca, Al and As were not extracted. Due to the irreversibility of copper extraction, its removal from solution was required prior to the extraction of nickel and cobalt. Zinc was not as strongly extracted (i.e. its stripping was readily achieved) as was copper . Flowsheets for the recovery of nickel and cobalt were also developed.

Jan 1, 1997

By R. K. Govila, E. H. Parkison

THE interplanar angles for hcp metals vary with c/a ratio, and therefore must be computed separately for each particular metal or alloy. Manual computation of these angles is laborious and time consuming, and for this reason computer programs have been developed to accomplish this task.1"3 However, these programs have certain disadvantages. For example, they require prior knowledge and understanding of ALGOL or FORTRAN languages. Further, they will not print out specific angles but instead give all angles between given limits—thus program2 prints out a total of 26,649 angles between planes with indices and in the range from (4 4 4) to (4 4 4) for any given c/a ratio. The purpose of this note is to present a simple and inexpensive computer program for accomplishing this task. This program is written in BASIC language4 which does not require any prior knowledge of computer programming, and is ideally suited for nonprofessional programmers. It also provides flexibility for the user by allowing him to select any indices for as many or few planes as desired for any given c/a ratio. The computer program proposed below is based on the relationship in which + is the angle between any two planes and . TO illustrate use of the program, consider the problem of calculating the interplanar an-

Jan 1, 1970

By Zbigniew Zurecki

The selection of atmosphere composition is critical for controlling surface quality of reactive aluminum alloys during solution treatments. An improper selection of annealing atmosphere can result in surface blistering in AI-Mg and sub-surface depletion of lithium in AI-U ingots. To determine optimum atmosphere compositions for homogenizing A1-Mg and Al-Li alloys, Ii number of exploratory experiments were carried out in air, nitrogen, and carbon dioxide based atmospheres including reactive impurities or additive such as moisture and sulfur hexafluoride. This paper describes the influence of these atmospheres on high-temperature oxidation and sub-surface defects. The results are discussed in terms of the change in Pilling-Bedworth ratio.

Jan 1, 1996

By Mario Bendezú Chalco

La estimación de un mineral contenido en un yacimiento minero es un paso importante en el proceso de explotación. En este sentido, el texto señala la valoración de depósitos masivos de mineral a partir de la técnica del "Krigeage", la cual determina un estado lineal óptimo y calcula no solo el error cometido en la estimación, sino minimiza el error estimado. Asimismo, para lograr la aplicación del marco teórico señalado, se describe un sistema de programas compuesto de rutinas en Algol-W y Fortran IV, desarrollándose una interacción entre ellas.

Nov 20, 1978

By Elisa Comis, Jeffrey Peterson, Yama Ebrahimi

Construction of the Northeast Boundary Tunnel (NEBT), the last leg of the Anacostia River Tunnel System on DC Water’s Clean Rivers Project, started in September 2018 and was completed in April 2021. The 26-foot-bore earth pressure balance (EPB) tunnel boring machine (TBM) mined 26,737 feet at elevations between 80 to 160 feet belowground. Approximately 55% of the tunnel was cut through lower predominantly coarse-grained facies identified as the Cretaceous Patuxent Formation (undifferentiated) (PTX), and the remainder was cut through upper predominantly overconsolidated fine-grained plastic material facies identified as the Cretaceous Patapsco/Arundel Formation (P/A). Mixed face conditions were encountered in the transition from the P/A to the PTX and vice versa. This paper reviews the performance of the TBM that mined the NEBT through several unique challenges, including 8,000 feet of tunneling under the heavily developed Rhode Island Avenue corridor, major sensitive structures, cast iron water distribution mains, and other sensitive utilities.

Dec 1, 2022

By R. R. Brandenthaler

The development of the Seminole area into one of the major oil-producing sections of the country has been accompanied by many innovations and departures from former methods of development. On July 1, 1929, two years and nine months from the date of discovery, 20,490 acres were considered proved, and additional acreage is constantly being developed. Because of its peculiar conditions, extent, and rapid rate of development, the Seminole area provided numerous problems, the solution of which necessitated research in connection with practical field operation; as a result, there was a radical departure from methods usually employed in the development of a new field in the Mid-Continent area.

Jan 1, 1930

By G. H. Bennett

A field experiment was performed in a production unit of an operating copper room and pillar mine to compare the support capabilities provided by resin and mechanical roof bolts. Resin and mechanical roof bolts were alternately installed in eight intersections in a single entry. Rock mechanics instrumentation was installed to measure roof sag, bed separation, convergence, bolt pullout, torque, and strain. Bolt cost and installation time are included. Two analyses of the test were made. The analysis of the rock mechanics data showed there was no definite difference between the two bolting systems. From a broader analysis on a mine-wide basis it was concluded that resin bolts gave better support. A critical view of the experiment is given in the appendix.

Jan 1, 1974

By A. Ansari

Standard depressants used in the selective separation of copper and molybdenum sulfides by flotation pose environmental and health hazards. In this investigation, the floatability of chalcopyrite and molybdenite in the presence of six well-characterized lignosulfonates was studied through Hallimond tube flotation and adsorption tests. The results define the physicochemical conditions (lignosulfonate type and dosage, pH, presence of ions) for possible selective separation of molybdenite from chalcopyrite. Dissolved polyvalent cations, especially calcium, appear to serve as "activators" for lignosulfonate adsorption on both minerals. From this point of view, the use of lime as a pH modifier is not always appropriate for optimum selectivity since high dosages of lime to produce high pH tend to indiscriminately depress both sulfides.

Jan 1, 2006

By Harlow D. Phelps

"INTRODUCTION The Copper Butte mine was examined, surveyed and mapped (fig. 1) by a Bureau of Mines engineer in January 1944. As a result, it was decided to diamond-drill the deposit, using Bureau of Mines equipment, and drilling was started October 14, 1944, under the supervision of two Bureau engineers, and stopped April 5, 1945. Nine holes were drilled for a total of 1,274 feet, not including 48 feet on a lost hole. Figures 2 and 3 are sections at AA' and BB' of figures 1, and show the adjusted average assays of drill-hole samples. Figures 4 and 5 are separate maps of holes 4 and 6, respectively.ACKNOWLEDGEMENTSIn its program of exploration of mineral deposits, the Bureau of Mines has as its primary objective the more effective utilization of our mineral resources, to the end that they make the greatest possible contribution to the national security and economy. It is the policy of the Bureau to publish the facts developed by each exploitation project as soon as practicable after its conclusion. The Mining Branch, Lowell B. Moon, chief, conducts preliminary examinations, performs the actual exploratory work, and prepares the final report. The Metallurgical Branch, R. G. Knickerbocker, chief, analyzes samples and performs beneficiation tests. Both these branches are under the supervision of R. S. Dean, Assistant Director."

Aug 1, 1946

By Robert S. Schechter

This report describes the development and application of PHASEQ/FLOW, a geochemical flow simulator capable of describing the dynamic changes in chemical composition of an aqueous solution during flow in a permeable medium. The solution components can react through intraaqueous reactions, redox, precipitation, or dissolution. The assumption of local thermodynamic equilibrium ensures maximum generality with respect to the number of species and components possible; however, the fluid flow itself is limited to one-dimension. The report describes several applications: generic batch equilibria, flowing equilibria, uranium roll-front deposition, and roll-front leaching.

Jan 1, 1985

By R. P. Bhagat

The paper reports results on sinterability of iron ores from the mines of Tata Steel Limited. The objective was to improve tumbler index (TI) of sinter and its reduction parameters, reduction degradation index (RDI) and reducibility (RI) while maintaining strand productivity same or to improve. Pot sintering experiments were carried out with Joda and Noamundi mines having LOI 3.8% and 2.9% respectively. Sinter basicity (CaO/SiO2) was varied in the 2.1 to 2.5 range and its MgO content was kept in the 1.4% to 1.8% range according to the blast furnace requirement. The ignition condition and vacuum was maintained according to the plant practice. The effect of variables namely, granulometric composition of ores vis-à-vis that of sinter mix, bed height, solid fuel, moisture content of green mix on the sintering indices was studied. The productivity with Noamundi ore (26 %+6.3 mm) was lower than that with Joda ore (45% +6.3 mm) at 4% coke in the mix and sinter basicity (CaO/SiO2) 2.1. However, with 4% coke (ash 22%) the RDI value was significantly high in case of Noamundi Ore, which decreased significantly to 29% with 5% coke. The size parameter of ore fines and its LOI content do influence the sintering speed and the sinter properties significantly. At 2.1 basicity ratio, the sinter with the Joda ore having coarsergranulometry had highest TI (=70.2%). The RDI (27%) in this case was inferior to that (23.2%) when Joda ores with finer size was sintered. Better RDI with finer sized ore could be attributed to better assimilation of CaO/ MgO with more balanced and uniformly distributed hematite minerals. The size parameter has been inter-influenced by the coke requirement. With the lower mean sized Joda ore the sinter RDI decreased significantly to 23% and the productivity improved to 42.9 T/(sq m*d) when the coke in the mix increased from 4% to 5%. An attempt to reduce the coke in the mix from 5% to 4% with respect to both the ores was not successful as it resulted higher RDI and lower strand productivity. The present study has revealed that sinter RDI improves (decreases) with decrease in the sintering time, while such correlation was absent between TI of sinter and speed of sintering. Corollary to this observation, one can take advantage of other stronger parameters to increase the sintering speed (and hence sinter productivity) without affecting the sinter strength. In the present study higher FeO sinters has displayed excellent RDI, however cold strength of sinter was not correlated with its FeO content. The TI and RI parameters of sinter improves marginally with increase in its MgO content while RDI got worsened. Keywords: LOI content, iron ore, reduction properties, sinter, noamundi, joda

Sep 1, 2012

By Louis J. Mittoni

"It is well known that gas injection systems can exhibit a wide range of dynamical behaviours, ranging from linear periodic bubbling through to highly complex turbulent jetting. Recently, it has been observed that an important intermediate regime exists under certain system conditions, where the dynamics are complex in nature yet predictable for short time periods. This paper reviews the evidence to support the above hypothesis, and discusses the invariant quantitative measures such as density, return maps, Lyapunov exponent and dimension which may be used as pattern recognition features in a mOnitoring and control strategy.INTRODUCTIONThere has been a great deal of research on the submerged injection of gases into liquids. This interest is primarily due to the large number of applications in the pyrometallurgical and chemical engineering industries. Gases are typically injected into liquids to achieve goals such as heat and mass transfer, or physical mixing and agitation. Only recently though has the possibility of using the evolution of the gas dynamics as a probe to internal system conditions been raised [1, 2].At very low gas injection rates and small upstream chamber volumes, gas normally disperses in the form of stable bubbles of constant volume [3]. With increases in gas flow rate, the dynamics become more complex, bifurcating into double bubbling, multiple bubbling and complex coalescence behaviour. Irregularities measured in pressuretime series acquired upstream of the injection port under these complex conditions have usually been treated as bothersome noise or contamination to be filtered from the signal and ignored in the analysis. These irregularities, however, may contain physically interesting and useful information on the system from which they were produced if the system may be classified as deterministically chaotic [4]."

Jan 1, 1996

By A. A. Holland

Introduction The world's largest known deposits of natural sodium sulphate (Glauber salt), generally termed 'alkali ' throughout western Canada, are located in the Province of Saskatchewan: reserves are estimated to exceed 200,000,000 tons. These are surface deposits resulting from the recent or present-day natural evaporation of brines, in which respect they are similar to those occurring in certain other parts of the world, as in semi-arid sections of the United States, Russia, Germany and Austria. In some areas, underground deposits formed hundreds of thousands of years ago have been _encountered in drilling, and indications are that they also were formed under arid or semi-arid conditions. The master key to the formation of deposits of natural sodium sulphate, wherever they occur, is a climate, either past or present, under which evaporation exceeds precipitation over a considerable period of time. Commercial development of the Saskatchewan deposits began about thirty years ago. Previously, the demand for sodium sulphate had largely been met by salt cake produced as a by-product in the manufacture of hydrochloric acid from common salt. The rapid increase in the production of Kraft paper and, more recently, the development of synthetic detergent materials, have caused a marked increase in the market for sodium sulphate. This chemical gives the extra toughness to Kraft paper and is used in detergent compositions in proportions as high as 75 per cent. Saskatchewan now has six commercial plants producing natural sodium sulphate. Production from each in the fiscal years 1947 and 1948 is shown in Table I. The newest and latest plant is that of Saskatchewan Minerals, at Chaplin, which 1s designed to produce up to 150,000 tons of salt cake, 98.5 to 99.5 per cent pure, yearly. This is equivalent to about 24 percent of the total United States production of crude commercial salt cake for 1947.

Jan 1, 1949

By Ivette E. Torres

The final 26 tables of this chapter, tables 24-49, extend and expand the statistical series on production that was started in the 1963 edition of the Area Reports: International volume of the Minerals Yearbook and that was subsequently updated and expanded in the 1965 and 1967-90 editions. Mainly because of the separation of the countries that formed the U.S.S.R., the column that provided a 5-year average, was deleted. The listing order of major producers, however, continued to be, as in past years, in descending order of rank in the year of review, 1992. This group of tables now includes each of the top 19 crude minerals in 1983 in terms of value of their output plus 3 others of lesser rank. These 22 crude mineral commodities accounted for more than 98 % of the estimated value of world crude mineral production in 1983. Coal production, included in the 1983 value of production table as two separated entries, is combined in one table in this chapter. World output of five key downstream products-aluminum, steel, cement, nitrogen in ammonia, and refined oil-is included because of their significance as products.

Jan 1, 1994

By G. Jenny

The particle size distribution of ground minerals is of decisive importance for downstream processes like floatation, separation, drying or others. In order to optimize the process efficiency on one hand and the final product quality on the other hand an early control of the grinding or classification stage is essential. The ultrasound based particle size analyser OPUS is capable of performing on-line particle size distribution (PSD) and solid content measurement of mineral slurries such as iron ore, copper ore, fluorspar, or quartz sand and alumina directly in heavy and rough process environment. The instrument provides a PSD of 31 size classes and can be applied for particles from nanometer range up to several millimetres. Arbitrary interpolations in between the 31 measured points are available. Typical residue values show an excellent agreement to off-line particle size analysis methods such as e.g. sieve analyses or laser diffraction. OPUS is designed as rugged in-line probe made from stainless steel. The applied technique is independent of product flow dynamics, contamination, optical properties, vibrations, pressures or changes in solid concentrations. The instrument provides all data on the system?s PC or on the process control system by a variety of interfaces.

Jan 1, 2014

By Sally A. Shoop

Thirty-seven blasts have been monitored using either three or four seismographs, at four coal strip mines and at a limestone quarry. Statistical analysis of the data shows that square-root, cube-root, and site-specific scaling methods predict peak particle velocities with about the same (low) degree of reliability. Some mines have peak particle velocities that are significantly lower or higher than the U.S. Bureau of Mines averages (Siskind et al., 1980). This suggests that the option provided by the proposed regulations (Office of Surface Mining, 1983), to adjust blast designs based on site-specific measurements could be highly beneficial both to operators and to the public. The frequency spectra reveal that the predominant frequencies were generally less than 50 Hz but several blasts had a significant amount of energy up to 125 Hz. In some cases the vibration energy was concentrated at frequencies corresponding to the delay intervals.

Jan 1, 1983

"Mining with blast holes drilled upwards may be done to recover sill pillars, or for economic reasons when the distance between the levels is relatively large. If the rock is sufficiently competent to accommodate large stope size, the distance between sublevels could be increased to as much as drilling accuracy allows. The same drill drift can be used for the drilling of both down holes and up holes. In the case of down holes, the initial opening of the stope (drop raise) is not as much a problem as for the inverse drop raise for mining with up holes. This is because, with a drop raise, a lot of space is available at the toe for the blasted rock to expand. In addition, the raise can be blasted in many shots, thus allowing smaller blasts each time. Inverse drop raises are generally much more difficult to blast because of the limited space for muck flow, and must, therefore, be taken down in a single blast, requiring special considerations in order to ensure a success. A case study of a 29 m (95 ft) inverse drop raise successfully blasted in a single shot at Heath Steele Mines is described. The paper covers technical considerations such as drilling accuracy, hole deviation survey, delay extension and protection, initiation methods and initiation sequence. Finally, a novel method for creating the initial opening called ’slot drilling’ is presented. This method, inspired from LKAB in Sweden, consists of drilling a row of interconnected holes using a special guide mounted on a regular production drill hammer.With a case study of blasting an inverse drop raise of 29 m (95 ft) in one blast, this paper further discusses some technical issues that are critical for the development of inverse drop raises. A novel method for creating the initial opening with a slot of interconnected holes is also presented with the experience acquired at different mine sites across the Noranda group."

Jan 1, 2000

By S. W. Zoldok

"ERRATUMFor paragraph 1, page 1, read the following:The Cle Elum nickeliferous iron deposits occur on an unconformable contact between the serpentine and overlying Swauk sandstone formation and extend about 2 miles along the Cle Elum River in Kittitas County, Wash.The linear extent of the deposits and their proximity to a large source of,electric power and coal supply indicated that a development program was in order to determine the probable grade, extent of the ore bodies, and a suitable metallurgical process for recovering the iron, nickel, and chromium from the ore.The northern portion of the serpentine formation was investigated by the Bureau of Mines from August to December 1943 and from August to October 1944. The investigation consisted of road building, diamond drilling, sampling, and metallurgical tests.The Geological Survey assisted with logging of cores and made geologic and topographic maps."

Feb 1, 1948

By B. K. Shibler, A. O. Ipsen, W. W. Agey

"INTRODUCTION As a part of the program of investigation of domestic sources of manganese ore, mining engineers of the Bureau of Mines obtained and examined samples of ore from six properties in the vicinity of Pioche, Lincoln County, Nev., and from one property near Caliente, Lincoln County, Nev. As the ores were too low-grade to be acceptable for the direct production of ferromanganese, their amenability to concentration by ore-dressing methods was investigated.In general, the Pioche ores had a low manganese content and, owing to extremely intimate association of manganese minerals with iron oxide and nonmetallic gangue, were refractory to concentration by ore-dressing methods. Only two samples (Zero Gap and Wheeler ores) were amenable to the production of concentrates that would sinter to a marketable plus 35-percent manganese grade. The Prince Consolidated and Ely Valley No. 1.ores were roasted and sintered to produce lead-silver-zinc fumes. The residues were of possible value as manganiferous iron ore. No marketable manganese products were made from Calton semi-oxidized ore, but over 80 percent recoveries of lead, silver, and zinc were made by bulk sulfide flotation followed by Diming of the sulfide concentrate. No satisfactory results were obtained by treatment of Golden Eagle and Ely Valley No. 2 ores.The Cudverwell ore was amenable to the production of high-grade manganese concentrates by ore-drssing methods. However, fine grinding was required to effect mineral liberation, and loss of manganese as slime limited the mangenese recoveries obtainable.In the coarse of the investigations, many data were obtained and compiled, but for the sake of brevity, several data, of secondary importance have been omitted or condensed, and only the tests giving the more promising results are discussed in detail. For convenience, the report has been divided into two parts, one opertaining to the Pioche ores and the other summarzing results obtained by testing Culverwell ore."

Aug 1, 1947

By H. A. Watson

Laboratory tests on three commercial methane detectors, two combustion-type detectors and one interferometer-type detector, were made by the Bureau of Mines to determine their response to certain single and multiple flammable gases mixed with normal and abnormal air atmospheres. Although both types of detectors responded accurately to methane-normal air mixtures, they did not show correct concentrations for other single flammable gases in air. Uniquely, the response of the interferometer-type detector to hydrogen was in a negative direction. The effects of individual gases in multiple flammable gas mixtures were approximately additive. In oxygen-deficient atmospheres the methane response of the interferometer-type detector erred on the high side, but only in very low oxygen concentrations were the combustion-type detectors affected-showing low, erratic methane readings.

Jan 1, 1966