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By P. J. Potter

PRACTICALLY all tin-base babbitt metals used in engine bearings are made to customers' specifications, which are many and varied. The copper ranges from 3 to 8 per cent. and the antimony from 4 to 13 per cent.; generally, the babbitt with lower copper content will contain from 4 to 8 per cent. antimony and that with higher copper will have from 7 to 13 per cent. antimony. The allowable lead content varies from 0.20 to 2.00 per cent. If a solder is used as a bonding material instead of tin, the resulting material in the finished bearing will have a higher lead content, but it would not be enough to bring the lead above specificational limits. Impurities such as iron, arsenic and bismuth should be determined in the tin before using to insure a uniform and high-grade product. These points must be considered when segregating and grading the waste that comes from the finishing operations on lined bearings.

Jan 1, 1929

By Gürkan Bacak

Study area is located on the NorthWestern of Yatagan-Yenikoy and placed in the units of the crystaline Menderes massif of Eagen, Turkey. Stratigraphically gneissic, migmatitic and metagranitic rocks are found at the base. Garnet schists, phyllitic rocks lie unconfirmitelly upon the basement rocks. Permian aged marbles can be observed as diferrent sized lenses within the schists. Triassic, Jurassic and Cretaceous aged gray colored dolomites and pure crystaline calcite bearing marbles lie upon the Permian aged schists. Neogen series, mainly composed of conglomerates, claystones, marl and limestones unconformly cover the other basement series, mentioned above. Pure calcite bearing marble occurances are found at 2 locations in the study area. These are known as Berber Quarry and Kavuk Quarry. Samples numbered as N7, N8, NA from the Berber Quarry, mineralogically composed of Calcite (97-99%)+iron oxide (1-3%) and chemically contain CaCO3 (97,98%), Fe2O3 (0.5-1%), SiO2 (0.025%) N9 and N10, sampled from the Kavuk Quarry-mineralogically composed of Calcite (94,95%)+iron oxide (2-3%)+albite-Quartz (1-2%) and chemically contain CaCO3 (92-93%), SiO2 1.49%, Fe2O3 0.42%. Especially in plastic and paint sector albite and quartz are unwilling minerals due to their hardness. Approximatelly 1/20 of the study area (87.500 km2) contains industrial calcite occurances. Moreover about 100 billion Tons geological, 1.86 billion tons runable (possible) calcite reserve calculated. It can be expected the calcite quality will be increased with depth. During the running stage of the quarries over burden removel and hand sorting processes will positive affect of the quality.

Jan 1, 2005

By R. C. Bunge

Many minerals float best with fatty acids in the intermediate pH range. For example, fluorite, a semi soluble salt mineral, exhibits a maximum contact angle and a maximum flotation recovery in the pH range of 6-8 after conditioning in a palmitate solution (fig. 1). The maximum in flotation coincides roughly, as many researchers have observed, with the boundary of bulk precipitation of the fatty acid. According to fig. Z this boundary is in the above case of 5xl0-7 M palmitate approximately at pH 6.3. For assessing the phenomena occurring at the bulk precipitation boundary of fatty acids, the surface tensions of carboxylate solutions have been measured under various conditions. Fig. 3 shows the surface tension development of palmitate and myristate solutions of increasing concentration at pH 12. Also shown are the bulk precipitation edges (BPE) of the respective solid species that is stable under these conditions, that is the potassium acid soap, HKAZ. Both curves display a similar behavior. As the concentration of carboxylat,e increases, the surface tension decreases, until a minimum is reached at which the curves level off. The decrease of surface tension with increasing carboxylate concentration is generally taken to indicate the surface excess of the carboxylate ion. The point where the curve suddenly levels off has not yet been explained. While it is well known that the onset of micellization (CMC) may cause such an inflexion of the surface tension curve, this cannot be the case here because the position of this point depends, as shown in fig. 4 for palmitate, on pH (the CMC is generally independent of pH). We believe that this point indicates the precipitation of a colloidal acid soap (colloidal precipitation edge, CPE) before the bulk precipitation of this species sets in (BPE).

Jan 1, 1994

By V. N. Krivobor

The study and use of low-carbon manganese steels have been curiously neglected in the general history of developments in alloy steels. Hadfield1 made an extensive study of manganese-iron-carbon alloys about 1886, which culminated in the wide application and use of Hadfield austenitic manganese steel. His alloys were nearly all high in carbon, as compared with the steels discussed in this paper, and he found a marked tendency toward brittleness in the alloys of medium and low manganese content, that is, below 7 per cent. manganese. As a result, there has been a widespread prejudice against the use of manganese steels containing between 1.0 to 3.5 per cent. manganese with comparatively low carbon. Steels of this composition have never been studied adequately in comparison with other alloy steels, and have had litttle use in practice. In a very recent paper by Sir Robert Hadfield2 the following statement appears: 6L... manganese-iron alloys with little or no carbon do not seem to offer any practical employment; they only become valuable in the presence of quite high percentages of carbon, 0.90 to 1.50 percent." The results of the present investigation are so contrary to the findings of Hadfield that the writers feel fully justified in presenting the preliminary report incorporated in this paper. Previous Investigations As early as 1886 the Terre Noire CO.3 in France produced alloys containing up to 2.5 per cent. of manganese, using ordinary low-grade

Jan 1, 1927

By W. F. Watts

In 1980 the Bureau of Mines developed the Mine Inspection Data Analysis System (MIDAS). MIDAS is a computerized, industrial hygiene data base capable of statistically analyzing environmental data collected in coal and noncoal mines and mills by Mine Safety and Health Administration (MSHA) inspectors or mine operators. The objectives of this report are to describe the current contents of MIDAS, to report analyses of coal and noncoal mine respirable dust samples collected by MSHA inspectors and to evaluate the proposed change in the metal and nonmetal respirable dust standard from a formula based upon the percentage of quartz identified in the sample to 100 µg/m3 of respirable quartz. Based on samples collected by MSHA inspectors, changing the noncoal respirable dust standard would result in 4 pct fewer samples with dust concentrations exceeding the standard. Analysis of respirable coal dust data collected by MSHA inspectors showed that mines with longwall plows or shears had the highest geometric mean concentrations (1.64 and 1.29 mg/m3, respectively). Mine operations using continuous rippers out-numbered longwall mine operations about 10 to 1 and had a geometric mean concentration of 0.66 mg/m3.

Jan 1, 1987

By H. M. Howe, W. E. C. Eustis

The processes which form the subject of this paper have been experimented on in the laboratory of W. E. C. Eustis, but have not passed beyond the experimental stage. The first is the invention of Mr. J. L. Thomson, of Capelton, Quebec, Canada, the others have been invented by the writers. Thomson's PRocess foR the Extraction oF Nickel. This consists essentially in first rendering the nickel magnetic, and then separating it from the materials with which it is mechanically vol. X.—20

Jan 1, 1882

By F. J. Fayers, R. L. Perrine

For many years the problem of increasing ultimate recovery of oil from a reservoir has been a subject of interest to the oil industry. At present, a standard secondary recovery technique is to flood the reservoir with water once natural forces of the system are depleted. The permeability characteristics of the rock, together with interfacial forces which exist between the two fluids and the porous material. allow only part of the oil in the rock formation to be recovered by the water-flooding process. Laboratory experiments have shown that when detergents are added to the flooding water, the flow properties of oil in a porous rock arc improved. This improvement results in greater oil recovery. Even though higher recoveries are obtained using detergents, the extra cost associated with the method may make it economically unsatisfactory. To establish economic feasibility requires experimental laboratory measurement of fluid and rock properties together with a calculational procedure to predict field results. Pilot tests in the field may also be required. This paper presents a mathematical procedure for predicting detergent flood behavior. A number of reasonable simplifying assumptions are made to obtain a tractable system of equations. The resulting method may be regarded as a generalization of Buckley-Lev-crett' theory to solve simultaneously for water saturation and detergent concentration profiles. Consequently this type of calculation can be used in much the same manner as Buckley-Leverett theory is used to evaluate a water flood. The mathematical method employed is the so-called method of characteristics for solving hyperbolic partial differential equations. This application of the method is instructive because several other problems in reservoir analysis may be analyzed in a similar manner. FLUID FLOW EQUATIONS The flow behavior of oil and water without detergent through porous reservoir rock is usually expressed by Darcy's law and a continuity equation for each phase. If gravitational forces are neglected, vrg = kr (s)µr v p rg.........(1) vrg = kr (s)µr v p rg.........(1) ? pa va = F ?/?t (sd) where v is the volumetric flux, k represents permeability, S is saturation, and P the pressure. Fluid viscosity is denoted by 11, p is the density, 4 is porosity, and I the time. The subscripts w and o refer to water and oil. The capillary forces in the system lead to a difference in pressure between phases. This may be expressed by the relation: Pm -P0 =Pc(S).........(5) The capillary pressure? P,, is determined experimentally as a function of saturation. DETERGENT BALANCE EQUATION Addition of detergent to the water phase affects the flow properties of the system. Capillary pressure and relative permeability become functions of detergent concentration, c, as well as fluid saturation. That is: P--P (S,c) and k,,,.- - -- k,,,. At low oil saturation values, the presence of detergent reduces capillary pressure and reduces the relative permeability ratio. Detergents are surface-active and adsorb on rock surfaces. The quantity adsorbed, a, will depend on the concentration c of detergent solution and may also depend on the saturation; thus, a = a(S,c). In this analysis we have assumed that the detergents used are water soluble but not oil soluble, and their movement is therefore restricted to the water phase. The dispersion of detergent in water is neglected by comparison with transfer by flow within the system. Detergent movement is determined by the water flux and adsorption: ? cv m = -F ?/?t (cs + a) We will assume that the quantity of detergent in solution is too small to significantly change water density or viscosity. When the permeability and capillary pres-

By T. Yamasaki, S. Usu

Adsorption of potassium dodecyl xanthate from aqueous solutions on artificial and natural zinc sul-fides was studied by means of infrared absorption spectroscopy. The adsorption species and their stabilities varied depending upon the conditions of the surfaces of the zinc sulfides. Adsorption products were analyzed after they had been removed from the surface with pyridine. Zinc dodecyl xanthate was confirmed for surfaces covered with oxidized products while dodecyl alcohol and carbon disulfide were detected on purified or weakly oxidized surfaces. It is of great significance to study the adsorbed species of collectors on the surface of sulfide minerals with a view of increasing our understanding of the mechanism of flotation. Compared with other methods, infrared spectroscopy promises to be of particular value in determining the nature of the species adsorbed at the mineral/solution interface since it gives direct identification of the adsorption products; and, furthermore, it has an advantage over the electron diffraction technique which has been employed in similar problems in that infrared spectroscopy utilizes radiation of very low energy so that the probability of changing the unstable surface films during examination should be correspondingly decreased. Infrared spectroscopic studies concerned with sulfide mineral flotation have already been reported by several investigators on zinc sulfide-hexanthi01' and lead sulfide-xanthate2,3 systems. The purpose of the present study was to investigate the adsorption of potassium dodecyl xanthate (KDX) at the zinc sulfide-aqueous solution interface by means of infrared spectroscopy. Rarely is the pure zinc sulfide-xanthate system encountered in practical flotation since zinc sulfide is usually activated with small amounts of certain metallic ions, such as copper ion. However, investigation of the pure zinc sulfide-xanthate system appeared promising for studying the fundamental mechanism of the adsorption of xanthate on the sulfide minerals. Although there are few cases where xanthates having an alkyl radical higher than hexyl are employed in practical operations, KDX was used in this study since it was reported that the adsorbability of xanthate on zinc sulfide was increased with an increasing number of carbon atoms of the alkyl radicals.4 EXPERIMENTAL Samples: Experiments were made on artificial zinc sulfide and natural sphalerite. The artificial zinc sulfide was obtained commercially from Dainihon Toryo Co. as a fluorescent pigment of the purest grade A. Considering the fact that there are often cases where the surface of sulfide minerals are apt to be oxidized so that the adsorption of xanthate at sulfide mineral/solution interfaces may be substantially affected, two different procedures were employed in preparing the samples of the artificial zinc sulfide. 1) The zinc sulfide was washed with hot concentrated ammonium chloride solution (300 g per liter) to remove surface oxidation products and followed by washing with deoxygenated hot distilled water by centrifugation until the constant electric conductivity of the solution was reached (Sample I) (specific conductivity of the solution = 8.6 x l0-5 ohm-' cm-'). 2) Sample I in a suspension of 5% by weight was oxidized with a 1.5% aqueous hydrogen peroxide solution for about one hour, and then was washed with distilled water as mentioned in the preparation of Sample I (Sample 11) (specific conductivity of the solution = 1.0 x 10"4 ohm-' cm-'). Both Samples I and II were dried under vacuum and stored in a vacuum desiccator. The specific surface areas of the samples determined by the BET method using carbon dioxide gas were 19 x l04 cm2 per g for Sample I and 35 x l04 cm2 per g for Sample 11. In addition, a sample which was derived from Sample I was also prepared. In 40 ml of 3 x 10-2 M zinc sulfate solution was placed 2 g of Sample I for 2 hours, washed with distilled water by successive centrifugation until no sulfate ion could be detected and dried under vacuum (Sample 111). The purpose of this treatment will be described later. Natural sphalerite was carefully selected by hand, ground in a mechanical agate mortar for about 40

Jan 1, 1965

By M. Sagisaka

The purpose of this study is to obtain carbon dioxide emissions by copper production systems and quantitative merit to use copper scraps in Japan. Electrolytic copper and sulphuric acid originating from the refining gas are produced in the system. In this study, the inventories such as the fuel consumption of the unit processes and the in-house electricity generation were obtained from published papers and public statistical data. The following observations were made based on the Life Cycle Assessment (LCA) method: (1) Carbon dioxide emissions from the production of electrolytic copper and sulphuric acid in the system are about 1.0 kg and 0.4 kg/kg-product respectively. The carbon dioxide emissions attributable to the transportation of copper concentrate correspond to 20% of the total emission. This emission is higher than that of zinc because the metal content in the concentrate is lower than zinc. (2) The carbon dioxide emissions from the system decrease with the recycling of copper scrap to the converting process because the consumption of copper concentrate is reduced. The reduction is estimated to be 0.18 kg-CO2/kg-Cu at the point of 0.1 kg-scrap/kg-blister Cu. This corresponds to 9% reduction for the present system. However, this recycling leads to the decrease of sulphuric acid by 450x103 tonne at the point. The recycling of scrap should be evaluated not only from the reduction of carbon dioxide emissions, but also in terms of sulphuric acid demands as well as advantage of waste management.

Jan 1, 2003

By G. E. Walden

The Bureau of Mines is currently engaged in a continuing investigation of the thermodynamic properties of certain inorganic compounds. As a part of this investigation, the heat contents of bismuth and cerous chlorides were measured throughout the temperature ranges of 370° to 630° K. and 370° to 1,200° K., respectively. Equations representing heat contents as a function of temperature were derived from the data by the method of least squares. These equations were used to calculate heat contents at selected temperature intervals ranging from the ice point to 650° K. for bismuth chloride and to 1,200° K. for cerous chloride; also, the heats of fusion of both compounds were calculated at their respective melting points. EXPERIMENTAL Materials The cerous chloride used in this investigation was supplied by the National Carbon Company of Cleveland, Ohio. A chemical analysis indicated Ce 56.57 percent and Cl 43.39 percent. No attempt was made to purify the compound or identify impurities since the analysis showed only about 0.04 percent total impurities. Reagent grade bismuth chloride was used without additional purification.

Jan 1, 1961

By M. S. Abrahams

Germanium has been rolled in the temperature range of 700o to 800°C. The thickness has been decreased by as much as a factor of four, from a thickness of 0.032 in. to a thickness of 0.008 in. For deformations below 60 pet, the true strain per pass is found to be a constant; from the temperature dependence of this slope, an activation energy of about 2.5 ev is obtained. This energy agrees with that for dislocation climb in germanium . For reductions greater than 60 pet, complete rings are seen in the Lave photographs, new grains are observed in the microstructure, considerable softening occurs, and the hole mobility is very low. This evidence indicates that the recrystallization of gertnanium has occurred. GERMANIUM has been deformed in many ways1 including tension, compression, torsion, and bending since Gallagher2 first described its plastic nature at elevated temperatures. All of these studies indicate that the glide plane in germanium is (111) and that the glide direction is (110). Rolled germanium specimens were used by Kolm, Warekois, and Kulin3 in their X-ray study of deformed semiconductors, but no information is given on the rolling itself. The present experiments deal with the rolling of germanium at various temperatures and for different orientations. In all previous deformation studies, the phenomenon of recrystallization (i.e., the transformation of a single crystal into a polycrystal) in germanium has not been observed4 despite relatively large deformations at elevated temperatures. The proposed reason4 for this was that sufficient energy could not be stored in the deformed germanium lattice. In contrast to the earlier studies this work will present evidence indicating that recrystallization occurs in germanium during rolling at an elevated temperature. I) EXPERIMENTAL PROCEDURE A) Test Specimens. The samples used for rolling were in the form of rectangular parallelepipeds measuring 0.3 in. long, 0.06 in. wide, and 0.035 in. high. They were cut from an undoped single-crystal ingot of p-type germanium with a resistivity of 24.4 ohm-cm, a Hall mobility of 2300 sq cm v-' sec-l, and a hole concentration of 1.1 x 1014 cm"3 at room temperature. The surfaces of the specimens were metallographically polished prior to rolling. The initial dislocation density of the samples was about 10' cm-' as determined by etching in CP4. Two different specimen orientations were used. In the first case, the direction of rolling was parallel to (251), the surfaces in contact with the rolls were of the form (1021, and the normal to the third face was parallel to (211). The corresponding di-

Jan 1, 1964

By L. M. Demers, R. E. Edelson, M. P. Rose, D. T. Superdock

The pulmonary alveolar macrophage is a major defensive cell which counteracts the invasive properties of bacteria and particles when these substances invade the pulmonary environment. Pulmonary exposure to coal dust particles is believed to activate these macrophages to release a host of d1emical mediators which can neutralize or contribute to the harmful effects of these dust particles. Our efforts have been concerned with assessing a specific family of mediator substances produced by the alveolar macrophage from arachidonic acid when these cells are in contact with activating substances such as coal dust. Metabolites of arachidonic acid produce a vast array of effects which can impact significantly on pulmonary function both with normal pulmonary events and with pathologic processes of the lung. Our studies demonstrate that isolated alveolar macrophages obtained from rats or guinea pigs cultured in vitro release appreciable amounts of the cyclooxygenase products prostaglandin E2 and thromboxane A2 and release significant amounts of the lipoxygenase products .5-HETE and LTB4. In the presence of l x 104 -1x10·7 g/ml of a coal dust suspension, alveolar macrophages from the rats and guinea pigs alters their pattern of arachidonic acid metabolite release. In the rat, exposure of alveolar macrophages in vitro to the higher concentrations of coal dust causes a significant reduction in PGE2, TXB2 and LTB4 in a 4 hour time course study. In contrast, macrophages from the guinea pig in response to coal dust had little change in TXB2 release, only a slight inhibition in PGE2 production and an initial stimulation in LTB.t release over the 4 hour time course. Cells from guinea pigs released considerably more TXB2 than the rat under these conditions while rat cells formed considerably more LTB4 than guinea pig alveolar macrophages. These findings support the following conclusions.

Mar 1, 1989

By V. Runolinna, R. T. Hukki

Preliminary separation of precious metals by flotation can offer a simplification of the conventional method of treatment of anode slimes. Laboratory flotation experiments show that rich gold and silver concentrate can be obtained with excellent recoveries. THE purpose of this paper is to present the results of an investigation into the possibilities of separating precious metals from anode slimes by selective flotation. The work was carried out at the State Research Institute in Helsinki, Finland. The sample of anode slimes tested was submitted by the Outo-kumpu Co. in Finland. In 1947 the average assay of filtered and dried anode slimes in the Outokumpu refinery in Pori was as follows: Au, 0.50 pct; Ag, 9.38 pct; Cu, 11.02 pct; Ni, 45.21 pct; Pb, 2.62 pct; Fe, 0.60 pct; Sn, 1.00 pct; Sb, 0.04 pct; As, 0.70 pct; Se, 4.33 pct; S, 2.32 pct; SO,, 2.17 pct; SiO2, 2.25 pct. The daily assay naturally varies considerably from the figures presented above. The present conventional method of treatment of anode slimes consists of the steps shown in the flowsheet in fig. 1. As seen from this simplified flowsheet, the present method of treatment involves many steps by which the components of the anode slimes are removed one after another until the main products, gold and silver, may be separated. Due to the small scale of operations, the above procedure is carried out in small batches requiring considerable amount of manual labor. If, however, the anode slimes could be treated in

Jan 1, 1951

By V. Runolinna, R. T. Hukki

Preliminary separation of precious metals by flotation can offer a simplification of the conventional method of treatment of anode slimes. Laboratory flotation experiments show that rich gold and silver concentrate can be obtained with excellent recoveries. THE purpose of this paper is to present the results of an investigation into the possibilities of separating precious metals from anode slimes by selective flotation. The work was carried out at the State Research Institute in Helsinki, Finland. The sample of anode slimes tested was submitted by the Outo-kumpu Co. in Finland. In 1947 the average assay of filtered and dried anode slimes in the Outokumpu refinery in Pori was as follows: Au, 0.50 pct; Ag, 9.38 pct; Cu, 11.02 pct; Ni, 45.21 pct; Pb, 2.62 pct; Fe, 0.60 pct; Sn, 1.00 pct; Sb, 0.04 pct; As, 0.70 pct; Se, 4.33 pct; S, 2.32 pct; SO,, 2.17 pct; SiO2, 2.25 pct. The daily assay naturally varies considerably from the figures presented above. The present conventional method of treatment of anode slimes consists of the steps shown in the flowsheet in fig. 1. As seen from this simplified flowsheet, the present method of treatment involves many steps by which the components of the anode slimes are removed one after another until the main products, gold and silver, may be separated. Due to the small scale of operations, the above procedure is carried out in small batches requiring considerable amount of manual labor. If, however, the anode slimes could be treated in

Jan 1, 1951

By Anjali Talekar

Low temperature heat capacities of pentaerythritol [PE: C(CH2OH)4], pentaglycerine [PG: (CH3)C(CH2OH)3], and 2-amino-2-methyl-1,3-propanediol [AMPL: (NH2)(CH3)C(CH2OH)2]have been determined by adiabatic calorimetry from 3 K to 300 K. To the best of our knowledge, this is the first reported heat capacity measurement below 280 K for PE and AMPL. The Debye temperatures for these organic crystals have also been determined and compared with other alcohol derivatives of neopentane.

Jan 1, 2006

Idaho Bureau of Mines and Geology, University of Idaho, Moscow, Ida. John W. Finch, Director. A list of publications will be sent upon application. A series of Bulletins and Pamphlets have been issued by the Bureau to date since 1920 Of the Bulletins, six are out of print, and a charge is made for eight. Each of the Bulletins, in the main, treats of the geology and resources of a particular district in Idaho, as follows (only available Bulletins listed): Bulletin 1, South central Idaho (1920), 15 cents, 7, North central Idaho (1924), 50 cents, 8, Bonneville, Bingham and Caribou counties (1924), 50 cents, 9, Boise Basin (1924), 50 cents; 10, Boundary County (1926), 50 cents; 11, Region about Silver City (1926), 50 cents; 12, Clark Fork district (1930), 50 cents, 14, Eastern Cassia County (1931), 50 cents, Press Bulletin 15, Teton County (1927), Bulletin 16, Melon Valley near Buhl (1927); 17, Concerning land slips near Whitebird, Idaho (1928) The 37 Pamphlets are issued free of cost, and each treats, also, in the main of the geology and resources of a particular district in Idaho Nos 1, 2, 3, 4, 5, 7, 8, 10, 17, 18, 20, 22, 25, 26, 30 and 35 are out of print Of those available, attention may be called to Pamphlet 6, Reported platinum occurrences near Coeur d' Alene (1925), 11, Bruneau River Basin, 12, Power and Oneida

Jan 1, 1933

By Mary L. Pearson

Ibis report summarizes the results of the contract. Included are summaries of existing legislation pertaining to outcrop barriers and a state-of-the-art survey of outcrop barrier designs and related, mine closure techniques. Six sites were inspected in the field and are presented as case histories The data analysis presented includes a computer modeled seepage analysis, an overburden blew-out analysis, and a wedge stability analysis. The results tit these analyses are interpreted to form recommendations for coal outcrop barriers which will minimize seepage and the potential for failure. Supplementary support and reinforcement alternatives are also discussed.

Jan 1, 1981

By Chee Theng

"So many talks, so little time.One of the toughest challenges associated with attending the SME Annual Conference and Expo is deciding how to allocate one’s resources. After accounting for keynote and plenary sessions, committee meetings, networking events, luncheons and exhibits, attending even one of the 109 technical sessions and more than 600 technical paper presentations can be a labor of love. Many, however, managed to make it to many of the sessions, including the mineral and metallurgical processing technical session on solvent extraction, ion exchange and electrowinning.At one point, that room was seated to near capacity, with a considerable number of the audience members standing by the walls at the back. Brittany Valera of Freeport-McMoRan Inc. was one who came early and enjoyed the session in its entirety. "Everything was pretty exciting," she said. "I really liked the modular plants. I think the future of mining, just like what we talked about in there, lies in thinking about things like remote locations, lifetimes of plants, anything that would be reusable and sustainable; and lower-cost and user-friendly would be really beneficial."Michael Moats, associate professor of metallurgical engineering at Missouri University of Science and Technology, started off the session by presenting on behalf of post-doctoral student Alex Luyima, who, like many before him, had been snapped up by industry and is now working for a secondary-metals refining company in Texas. Their team studied the nucleation and growth mechanism of copper on stainless steel from synthetic acidified copper sulfate in the absence and presence of chloride ions and three commercial organic additives: Hydrostar 4208, DXG-F7 and Cyquest N-900. Currenttime data were analyzed using known models, with reference to scanning electron microscope images. Good agreement was achieved between the models and SEM micrographs of deposits at a commercially relevant current density of 30 mA/ cm2. The addition of 20 mg/L chloride was found to increase the size and reduce the number of nuclei. The addition of 2.5 mg/L of each additive did not change the mechanism, but all three reduced the size and increased the number of nuclei, leading to more uniform coverage of the substrate with smoother deposits produced in twohour electrowinning experiments. N-900 had the best deposition coverage while DXG-7 was the easiest to dissolve."

Jan 1, 2014

By Brian Gettinger, Jim Schlaman, Alston Noronha

"INTRODUCTION The public understanding of green solutions today is based on the definition of sustainability adopted by the Brundtland Commission (World Commission on Environment and Development) in 1987: “development that meets the needs of the present without compromising the ability of future generations to meet their own needs.” Over time this initial definition evolved to identify three distinct factors impacting sustainability that are often referred to as the “Triple Bottom Line”: Economic, Environmental and Social. The triple bottom line approach seeks to drive outcomes that create maximum value for all stakeholders. In the last ten years purveyors of water and wastewater tunnel solutions have found themselves on the wrong side of a politically polarizing issue in the crosshairs of politicians, environmental activists and community groups branding tunnels as expensive, “gray” and not-sustainable. Tunnels under design were stopped and large planned tunnel programs were delayed or canceled. Therefore being sustainable and “green” is not simply using natural vegetation, but creating an asset that meets current and future needs and will not become a future liability. As this paper will discuss, tunnel projects embody a sustainable triple bottom line project well, are equally sustainable as green infrastructure, and have begun to gain awareness for their sustainability. GREEN INFRASTRUCTURE CHANGES TUNNELING LANDSCAPE The green movement quickly swept across the nation in the mid to late 2000’s and was a hot topic in the media and at all the local, regional and national industry conferences. Politicians espoused the benefit of green infrastructure including job creation, urban renewal, aesthetics, property values economics and sustainability. The political microscope was focused the closest on stormwater and wastewater management, particularly in communities responding to combined sewer overflow (CSO) consent decrees from the Environmental Protection Agency (EPA). As communities with CSO problems evaluated their long term control program (LTCP), local government officials and planners began to balk at the huge price tag required for compliance and began looking for alternatives. “Green” infrastructure was proposed as lower cost solution that could be used to offset capital-intensive “gray” infrastructure like new sewers, storage tanks, tunnels, and treatment facilities. In addition, including green infrastructure in a previously negotiated LTCP required a reset on the entire planning process, additional studies and more planning which would push capital investment further off into the future, subsequently delaying unpopular user rate increases. As a result, tunnel projects as well as trenched conveyance and treatment plant projects that had not yet started construction were stopped, delayed or substantially changed."

Jan 1, 2016

By H. F. Yancey

One of the important duties of the Bureau of Mines is to sample and analyze coals and to publish the results of such analyses for the information of producers, consumers, and the general public. Numerous publications containing such analyses have been Issued from time to time. Although the chemical properties of a coal as revealed by its proximate and/or ultimate analysis and heating value aid one considerably in visualizing its probable behavior and in determining its usefulness and value for a specific purpose, they do not furnish complete information. The physical properties of a coal, such as its ability to retain its original form without undue breakage or degradation in size under the various conditions of storage and usage, are also of importance in determining its suitability, technically or economically, for a given purpose.

Jan 1, 1932