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The selection of a particular machine for production drilling is the most critical drill evaluation the pit engineer is called upon to make. It is a true engineering design problem requiring value judgments. Generally, the procedure follows these steps: (1) Determine and specify the conditions under which the machine will be used, including such service factors as labor, site, weather, etc. (2) State the objectives for the rock-breakage phases of the production cycle of operations--considering excavation and haulage restrictions, crushing capacity, production quota, and pit geometry-in terms of tonnage, fragmentation, throw, etc. (3) On the basis of blasting requirements, design the drill-hole pattern (hole size and depth, in- clination, burden, spacing, etc.) (4) Determine the drillability factors and select the drilling methods which appear feasible for the kind of rock anticipated. (5) Specify the operating variables for each system under study, considering drill, rod, bit and circulation fluid factors. (6) Estimate and compare performance parameters, including costs. Major cost items are bits, drill depreciation, labor, maintenance, power and fluids. (7) Select the drilling system that best satisfies all requirements with the lowest over-all cost.

Jan 10, 1967

By R. T. Jones

Slags have been produced as by-products from pyrometallurgical processes for thousands of years, and have generally been regarded as waste. Many of these slags are no longer seen as residues merely to be discarded, but as potential economic sources of metals, or as useful by-products in their own right. Slag cleaning can enhance the recovery of valuable metals in existing pyrometallurgical processes, or can produce economic value from recycling old slag dumps. For example, a process has been developed and implemented industrially for recovering cobalt from copper smelting slag in a DC arc furnace. The relatively non-leachable behaviour of glassy slags allows them to be used as a very safe means of disposal of metallurgical waste streams, including many that are classified as hazardous. The high temperatures, reducing conditions, and good mixing that can be achieved in a DC arc furnace enable the effective functioning of this environmentally beneficial means of disposal. Lead blast furnace slag can be rendered safe for disposal by treating it using the Enviroplas process, which strips most of the hazardous lead from the slag (and traps the rest in an insoluble glassy slag) and recovers economic quantities of zinc by absorbing (in a lead splash condenser)the zinc vapour that is fumed off in the furnace. Another example can be seen in the recovery of a chromium- and nickel-containing alloy from stainless steel plant dust, while producing a disposable residual slag. The examples presented here illustrate that it is possible to develop processes that are both economic and environmentally beneficial. Keywords: DC arc furnace, plasma, slag cleaning, cobalt recovery, zinc fuming, Enviroplas, jigging, re-melting fines, environmental, economic

Jan 1, 2004

By Yuanbo Zhang, Zhixiong You, FENG ZHOU, Guanghui Li, Zhengwei Yu, Zhiwei Peng

Reduction disintegration of sinter significantly affects the coke consumption and productivity of blast furnace smelting. As we know, the reduction disintegration index (RDI+3.15) of sinter obtained from titanomagnetite concentrate is relatively worse than those from ordinary iron ores. In this study, the effect of sintering parameters, mainly involving coke breeze dosage and basicity on sintering indexes was investigated using titanomagnetite concentrate as raw material in an experimental-scale pot. Subsequently, RDI+3.15 of the sinter was detected according to the Chinese standard of GB/T13242-91. The results show that RDI+3.15 rises with the increase of coke breeze dosage, while it decreases with increasing basicity from 0.5 to 2.0 and then increases in the basicity range of 2.0-3.0. Finally, the microstructure of sinter before and after reduction was studied. And the mechanism of reduction disintegration was preliminary revealed by analyzing the morphologies and distributions of minerals in the sinter.

Jan 1, 2015

By William Petruk

"Heap leaching is a developing technology for recovering native gold and electrum from low grade deposits and from tailings. Recovery depends on permeability of the rock and ore minerals, size of particles in the heap, and ore textures that influence exposure of gold grains to cyanide solutions. These ore textures include gold-bearing veinlets and microveinlets along fractures and microfractures, gold grains in porous minerals and rocks, and gold graim. occurring along grain boundaries of other minerals. On the other hand, small encapsulated gold grains arc not likely tote exposed even with fine grinding. Most gold grains that occtir along grain boundaries of other minerals can be exposed with a moderate to fine grind, but the. resulting material will be too fine-grained to be permeable in a heap. Such finely ground ore, as well as tailings from flotation operations, can however be prepared for heap leaching by agglomerating the material into porous briquettes. Oxidized and weathered zones above. orebodies are frequently amenable to heap leaching because the gold-bearing pyrite and arsenopyrite have become permeable by conversion to porous iron oxides and ferric oxyhydroxides. A review of ore textures in several types of gold deposits suggests that:(1) the gold in vein deposits would gtmerally be amenable to heap leaching of both oxidized ores and fresh non-refractory ores,(2) the gold in Carlin-type deposits and in volcanogenic massive sulfide deposits is not likely to be amenable to heap leaching fresh ore, but oxidized zones above the orebodies are generally amenable to cyanidation, and(3) the gold in porphyry copper-gold deposits and in Witwatersrand-type deposits would likely be amenable to heap leaching of both fresh and oxidized ores but with high cyanide consumption."

Jan 1, 1997

By H. P. Rue

The Bureau of Mines has recently collected two samples of crude oil from wells in the Greasewood Flat area of northeastern Colorado. Sample 31310 was taken from the Continental Oil Co.'s well Briggs No. 1 which care in or September 27, 1931, with a maximum production of 940 barrels per day. Sample 31311 was taken from tie Reiter-Foster Oil Co. Is well Ida Johnson No. 1 which came in on August 24, 1931 with a maximum production of approximately 1000 barrels per day.

Jan 1, 1932

By J. R. Eckel

It has long been known that mud properties affect drilling rate and that drilling with water is as much as six to .seven times faster than with mud. However, it is not known why drilling rates with mud are lower. Recent studies show what fluid properties govern microbit drilling rate and also provide a quantitative correlation of these fluid properties and hydraulics with microbit drilling rate. All the microbit tests reported in this paper were made with a low permeability (about 10 md) limestone. They were conducted at constant bit weight and rotary speed with varying fluid properties, flow rate Q and nozzle dinnteter d. The tests showed that (1) drilling rate in a given system with constant circulating rate and nozzle velocity is a function of the kinematic viscosity [viscosity /density, (cp)/ p (density)] of the drilling fluid measured at near bit nozzle shear rates; (2) the combined effect of fluid properties and hydraulics on microbit drilling rate is defined by a Reynolds number function (kQp/dp); (3) for the same kinematic viscosity, drilling rate is independent of solids content; and (4) for the same kinematic viscosity, drilling rate is independent of fluid loss. INTRODUCTION The fact that mudding up reduces rate of penetration is well known, but the reduction varies from well to well. The rate with mud may be 80 percent of the water rate or it may be as low as 15 percent. Since this reduction of up to seven-fold takes place under conditions of constant bit weight, rotary speed and mud circulating rate in a uniform formation, it can only be a result of the change in fluid properties. Previous work1-" both in field tests and in laboratory microbit tests) showed that drilling rate with mud is lower than with water (Figs. 1 and 2). Microbit tests also confirm, at least qualitatively, the field observation that drilling rate slows with increased pressure differential from borehole to formation (Fig. 3). The qualitative effect of drilling rate of bit weight, rotary speed and rate of mud circulation are also the same for the field and microbit rig. For these reasons, the industry generally accepts microbit results as being qualitatively meaningful in terms of field application.

By V. I. Lakshmanan, Dan A. Mackie

Traditional vat leaching methods have had limited success, primarily due to the high cost of loading and unloading the vats. In general, such batch methods are labor-intensive and costly. Heap leaching has emerged as a viable, low- cost alternative, but low recoveries, normally in the 70% range, offer opportunities for improvement. Also increased regulatory guidlelines for effluent and spent heap leach pads disposal offer potential for alternative methods. The Mackie Vat Leaching Jig (MVLJ) has had its incubation at Ortech International, where bench scale through pilot scale testing continues. Design developments and testwork over the past two years indicate that the time may be right for field trials.

Jan 1, 1990

By S. Mostaghel, S. Nicol, M. Y. Solar

Once upon a time, the process engineer developing the design criteria for a new saprolite ferronickel smelter had it easy: most ores were around 2.5% Ni, with a Fe/Ni ratio of 4 to 5 and a SiO2/MgO ratio of about 1.6; to use the French word: garnierites. The ferronickel grade selected was the conventional 20 to 25% Ni and the impurity levels could be predicted from well established [C], [Cr] and [Si] vs (FeO) graphs. However the process engineer can no longer depend on statistics to design smelters: Ni grades are decreasing while the goethite contents are increasing; SiO2/MgO ratios vary from 1 to 3; and Al2O3 concentrations are reaching levels that cannot be ignored. Mechanistic models must be developed to select or predict essential parameters such as kiln and furnace reductions, ferronickel grade, slag losses, metal and slag liquidus, operating temperatures, etc. But these models must be simplified so that they can be used on a routine basis; and they must be calibrated against a wide range of commercial operations in order to yield the most realistic predictions possible. The present paper proposes one possible approach, using FactSage as a basic source of thermodynamic data. The predictions thus obtained are compared to actual performance for two well documented operations, as well as to the predictions made with other tools that might be more accessible.

Jan 1, 2014

By R. Daignault et G. O. Allard

The Chibougamau area represents a part of the Abitibi greenstone belt. The rocks constitute a volcanic pile (Roy Group) overlain by a volcano-detritic sequence (Opemisca Group). Three important periods of tectonic deformation have been distinguished. The first one produced folds with north-south horizontal axes. The second one is responsible for the isoclinal east-west folds, and the associated regional schistosity. Reverse faulting contemporaneous with this period of deformation, produced two distincts effects. In some cases the faults cause a repetition of the stratigraphic sequence. Whereas in others the faults truncate second period folds. Domes and basins interference pattern are produced by the superposed effect of Di and D2 deformations. The motion of these two periods would be more or less contemporaneous. The deformation could be generated by rising diapirs of early plutons combined with the progressive formation of troughs by gravitational subsidence of denser strata. The rising diapirs of late granitoid plutons produces a wraparound of the host strata.

Jan 1, 1984

By Claude Bazin, Jalna Lamontagne

"The operators of mineral processing plants collect daily samples from strategic process streams with a view to prepare production balances to assess plant performances. The rules to minimize the risk of systematic sampling errors are known and applied in many mineral processing plants. The mass of the sample to be collected is calculated to yield a target measurement reproducibility considering the fundamental error associated to the sampling of heterogeneous material. This paper demonstrates that this practice is partly valid if one does not account for the time variation of the ore composition during the day. The concept is demonstrated using samples collected on a 30 minute basis from different streams of a gold ore concentrator. Results show that depending of the natural variability of the stream characteristics the mass of the daily samples may not be the critical variable to obtain reproducible measurements. On the other hand the number of cuts taken during the day could impact on the variance of the measurements obtained from daily samples.IntroductionMineral processing plants may treat several thousand tons of ore every day to produce concentrate or impure gold ingots. The operation and performances of these plants are monitored on a daily basis through the collection of ore samples from various streams of the processing circuit. The samples are prepared and assayed to obtain the concentrations of target elements that are subsequently used to calculate the mass flowrates in the streams of the circuit and ultimately the distribution of the target metals for the estimation of the plant performances (Morrison, 2009; Lachance and Leroux, 2016).The acquisition of representative and reproducible samples is therefore the first step in the characterization of plant performances. The term representative sample is used here to indicate an unbiased sample, i.e. a sampling procedure that does not introduce a systematic error. Rules for the collection of unbiased samples are reviewed in the literature by different authors (e.g. Morrison, 2009) and are not discussed in this paper. The term reproducible indicates the dispersion of the measurements around the average value of a characteristic of a stream meets an acceptable level of variance. The reproducibility of a measurement process (sampling and analysis) is assessed by the relative standard deviation or coefficient of variation of the measurement that is a function of the sampling and assaying errors (Morrison. 2009; Gy, 1979). Usually the focus is put on the fundamental error of sampling whose variance can be controlled by the choice of the primary sample mass or adequate particle size reduction during the preparation of secondary or tertiary samples extracted for the chemical analysis. When a sample is taken from a stream that exhibits a time varying characteristic, the obtained measurement exhibits a variability that is not only a function of the sample mass but also of the natural variability of the ore in the sampled stream. This paper examines this aspect of the sampling of a time varying process on the reproducibility of composite samples for a day of production."

Jan 1, 2017

By S. Ubaldini

Acid mine drainage (AMD) is a common problem in different areas with a past history of mining activities, which is characterized by low pH (2-4.5) and significant toxic metals concentration. The main aim of the present work was to perform a process feasibility analysis in order to remove heavy metals (Cd, Zn, Ni, Mn, Cu) from AMD (Acid Mine Drainage) in a relatively cheap and environmentally friendly way, by means of electrowinning and biosorption. A first characterization of an Italian AMD sample was performed evidencing a zinc concentration around 2 g/L, cadmium and nickel content of about 4 mg/L, manganese of 85 mg/L and iron 190 mg/L. Electrowinning tests lead to the following metal removal after three hours treatment: Zn 99%, Ni 99.9%, Cd 99.9%, Cu 99%, Mn 87%, Fe 96%. Moreover, an high grade of purity of the metal deposit has been achieved (Zn>95%), as observed by X-ray diffraction analysis. Considering that metals concentration in the effluent was still above legal limits (in particular for Zn, Mn and Fe), a further biosorption treatment was planned in order to produce an effluent fitting environmental limits. Experimental electrowinning tests and literature multimetal column biosorption data have been used in order to perform a preliminary techno-economic feasibility analysis of the process aimed at metal removal from AMD. A treatment cost of about 6.5 ?/m3 AMD has been estimated, for a plant capacity of 10 m3/h AMD inlet flow rate.

Jan 1, 2006

By J. Daavittila

In the latter part of the 1980s Outokumpu Chrome in Tornio, Finland, was in a situation when its twenty-year-old ferrochrome plant was becoming too inefficient to sustain economically sound production. The company made extensive studies on the then available processing methods to find out the best possible processing route. As a result, the whole plant was practically rebuilt and expanded. When equipment was proven in practical operation, an application for FeMn production was developed. Now as the Tornio FeCr-plant is considering expansion, the same type of exercise is to be performed with today?s challenges, which will be discussed in the paper. These challenges include increasing costs or decreasing quality of raw materials, increasing energy costs, stricter environmental regulations and demand for better working conditions. The possibilities of resolving to these challenges will be discussed in the paper. The future and continuing development with FeCr includes the better utilization of process dusts and a lower consumption of energy. By adapting the latest automation tools to better control the process, even higher efficiencies can be achieved with present technology. New processes are considered for development in the future and some possible technologies will be described.

Jan 1, 2004

By J. Gurland, A. Gangulee

The cracking of silicon particles embedded in an aluminum matrix occurs progressively over the range of plastic deformation of the composite specimen. The fracture probability of the particles increases with increasing particle size and decreasing silicon contents. The crack orientation tends to be perpendiculay to the direction of the maximum tellsile strain. An example of a direct association between matrix slip and particle cracking is shorn. ALUMINUM-SILICON alloys of commercial compositions fail by ductile fracture in three stages:' I) initiation of cracks in the silicon particles, 2) growth of cracks into cavities, and 3) rupture of the aluminum matrix separating the cavities. The present work is concerned with the first stage: the initiation of cracks in the silicon particles. EXPERIMENTAL PROCEDURE Aluminum samples with 2.8, 6.1, 9.6, and 13.2 vol pet Si, respectively, were cast from commercial al- loys. Machined tensile specimens (2 in. gage length) were annealed in air at 1000°F for 100 hr, and then pulled at a strain rate of 0.025 per min. The grain size (average linear intercept) of the aluminum matrix was 0.24 and 1.6 mm in the 6.1 and 13.2 pet Si alloys, respectively. The particle size of silicon in alloys of one composition (6.1 pet Si) was varied by either modifying the castings with 0.15 pet Na or prolonging the annealing time. The average particle size was measured by linear and planar analysis, assuming spherical particles of uniform size. The particle sizes and compositions of all samples are tabulated in Fig. 8, together with the identifying symbols used in the graphs. The respective numbers of broken and unbroken silicon particles were determined from metallographically prepared longitudinal sections by counting a total of approximately 2000 particles per sample. EXPERIMENTAL RESULTS 1) Crack Initiation During Deformation as Function of Composition. Nominal stress-strain curves of four specimens of different compositions, but approximately equal particle sizes, are presented in Fig. 1. The fraction of broken particles, P (no. of broken particles/ total no. of particles), is shown in Fig. 2 as function of true stress and in Fig. 3 as function of nominal strain. The last point of each composition line in Fig. 2 rep-

Jan 1, 1968

By J. C. Taylor

The Rhodax inertial cone grinder, designed by France?s FCB Group Fives, is the result of three years, theoretical and mechanical research in the field of compression grinding by the research staff of FCB?s CRM minerals research centre. A number of potential uses have been assessed and will be discussed in the paper. The crusher is an inertial grinder that works on the pressurized bed fragmentation principle. The fragmentation force is caused by the rotation of unbalanced masses rather than by an eccentric mass, as is the case in a conventional crusher. This makes it possible to achieve very high reduction ratios. By controlling the speed of rotation of the unbalanced masses, the grinding force can be modified, thus changing the product size distribution. The paper describes the machine layout, operating principles, control parameters and will briefly describe the results obtained on reef, waste and ROM reject pebbles. Some comparisons are made with conventional crushing.

Jan 1, 1998

By Earl L. Rau

Although the Sagasca deposit has been known for 76 years, the property was never put into successful operation because of various adverse factors including low market price for copper, legal entanglements, unsuccessful financial arrangements, and an inadequate metallurgical process. Late in 1963, Continental Copper & Steel Industries, Inc., obtained legal control of this property. Since that time there has been a concentrated effort to complete the necessary mine appraisal, process development, and engineering design, and to solve the legal and financial problems to bring this property into production.

Jan 1, 1970

By M. Metzger, J. C. Bilello

Microyielding in 99.999 pct Cu occuwed in two distinct parabolic microstages and was substantially indeoendent of grain size at the relatiz~ely large grain sizes stzcdied. The strain recouered on unloading was a significant fraction of the forward strain and was initially higher in a copper-coated single crystal than in poly crystals. Results were interpreted in terms of cooperative yielding and short-range dislocation motion activated otter a range of stresses, and a formalism was given for the first microstage. It was suggested that models involving long-range dislocation motion are more appropriate for impure or alloyed fcc metals. THERE are still many unanswered questions concerning the degree and origin of the grain size dependence of plastic properties. In the microstrain region, a theory of the stress-strain curve proposed by Brown and Lukens,' based on an exhaustion hardening model in which the grain boundaries limit the amount of slip per source, accounted for the variation with grain size of microyielding in iron, zinc, and copper.' This theory assumes N dislocation sources per unit volume whose activation stress varies only with grain orientation. Dislocations pile-up against grain boundaries until the back stress deactivates the source, which leads to a relationship between the axial stress and the strain in the microstrain region given by: where G is the shear modulus, D the grain diameter, a the flow stress, and a, is the stress required to activate a source in the most favorably oriented grain.3 If this or other grain-boundary pile-up models are correct, then the reverse strain on unloading would be much larger for a polycrystalline specimen than for a single crystal. Also, the microplasticity would become insensitive to grain size if this could be made larger than the mean dislocation glide path for a single crystal in the microregion. These questions are examined in the present work on polycrys-talline copper and a single crystal coated to provide a synthetic polycrystal. EXPERIMENTAL PROCEDURE Tensile specimens 3 mm sq were prepared from 99.999 pct Cu after a sequence of rolling and vacuum annealing treatments similar to those recommended by Cook and Richards4-6 to minimize preferred orientation. Grain size variation from 0.05 to 0.38 mm was obtained by a final anneal at temperatures from 310" to 700°C. Dislocation etching7 revealed pits on those few grains within 3 deg of (111). For all grain sizes dislocation densities could be estimated as -107 cm per cu cm with no prominent subboundaries. The single crystals, of the same cross section, were grown by the Bridgman technique with axes 8 deg from [Oll] and one face 2 deg from (111). An anneal at 1050°C produced dislocation densities of 2 x 106 cm per cu cm and subboundaries -1 mm apart in these single crystals. A Pb-Sn-Ag creep resistant solder was used to mount the specimens, with a 19 mm effective gage length, into aligned sleeve grips fitted to receive the strain gages. All specimens were chemically polished and rinsed8 to remove surface films just prior to testing. The synthetic polycrystal was made by electroplating a single crystal with 1 µ of polycrystalline copper from a cyanide bath. Mechanical testing was carried out on an Instron machine using two matched LVDT tranducers to measure specimen displacement, the temperature and the measuring circuit being sufficiently stable to yield a strain sensitivity of 5 x 107. At the crosshead speeds employed, plastic strain rates were, above strains of 10¯4, about 10¯5 per sec for polycrystalline specimens and 10-4 per sec for the single crystals. Plastic strain rates were an order of magnitude lower at strains near l0- '. A few checks at strain rates tenfold higher were made for reassurance that the initial yielding of polycrystalline copper was not strongly strain-rate dependent. Test procedures followed the general framework outlined by Roberts and Brown.9,10 An alignment preload of 8 g per sq mm for polycrystals, and 2 to 4 g per sq mm for single crystals, was used for all tests. These gave no detectable permanent strain within the sensitivity of the present experiments; although at these stress levels, small permanent strains are detectable in copper with methods of higher sensitivity.11 12 stress and strain data are reported in terms of axial components. RESULTS General. The initial yielding is shown in the stress vs strain data of Fig. 1. For polycrystals, cycle lc, the loading line bent over gradually without a well-defined proportional limit, and almost all of the plastic prestrain appeared as permanent strain at the end of the cycle. The unloading curve was accurately linear over most of its length with a distinct break indicating the onset of a significant nonelastic reverse strain at the stress o u, indicated by the arrows. The yielding in subsequent cycles, Id and le, had the same general character. The single crystal behavior, shown to a different scale at the right of Fig. 1, was different in that initially the nonlinear reverse strain was unexpectedly much greater than for polycrystals. It should be noted that these soft crystals had a small elastic

Jan 1, 1970

By M. E. Bell

The term "operational research" was probably first used to describe work started under E. C. Williams, now Director, SHAPE Air Defense Technical Center, late in 1937 or 1938, at the Bawdsey Research Station of the British Air Ministry, a laboratory center concerned with the development of radar equipment. After the practicability of the early techniques had been demonstrated, a large (for those days) program of development and installation was authorized. It was very soon realized, both by the Royal Air Force and by the scientists that almost as important as the gear itself was the way in which it should be used. Accordingly, it was decided that some scientists should cooperate to study the way in which the equipment should be deployed and operated in conjunction with the Royal Air Force. To distinguish this work from the normal work of a research and development establishment, the term "operational research" was coined. It merely meant at this time that this particular section of scientists was to be concerned with the use of the gear rather than with its technical development and it seemed natural to those concerned to adopt the word "operations" which has a specific connotation in the armed forces.' This method was later extended to peacetime business enterprise, government operations and other human activities. Operations research appears to have penetrated the extractive industries more slowly and less completely than other industries, the military, or the government. This may be due (1) to a difference in the attitude of management towards operations research, or towards research of any kind, for that matter; (2) to unsuitability of the extractive industries for application of the operations research method; (3) to inaccessibility of the data; (4) or to a lack of trained personnel who are interested in applying operations research to the mineral industries.

Jan 8, 1963

The following is a 'partial list of members and guests who called at Institute headquarters during the period Oct. 10, 1917, to Nov. 10, 1917. Edwin T. Blake, Berkeley, Cal. Alfred C. Lane, Tufts College, Mass. H. M. Boylston, Cambridge, Mass. W. G. Matteson, Houston, Texas. W. B. Cogswell, Syracuse, N. Y. E. Francis M'Crossin, Birmingham, Ala. Paul R. Cook, Zaruma, Ecuador. R. E. Murray, Butte, Mont. F. W. DeWolf, Washington, D. C. Edmund Newton, Minneapolis, Minn. A. Faison Dixon, Venezuela. J. J. Ormsbee, El Paso, Texas. W. H. Dufur,, Oil City, Pa. Pablo Ortega, Havana, Cuba. Maxwell E. Erdofy, Lieut. Engr. Officers'. W. E. Pomeroy, El Paso, Texas Reserve Corps, New York. J. C. Ralston, Spokane, Wash. Evan Fraser-Campbell, Scotland. W. L. Remick, Chrome, N. J. David B. Gemmill, Crown King, Ariz. Howard D. Smith, San Francisco, Cal. F. Lynwood Garrison, Philadelphia, Pa. Harold C. E. Spence, Steeple Rock, N. M. C. J. Hall, Spassky, Siberia. R. K. Stockwell, Salt Lake City, Utah. H. Hamada, Tokyo, Japan. Maurice W. Summerhayes, Timmins, Rush M. Hess, Bouse, Ariz. Ont., Canada. A. Howard Higgin, London, England Malcolm M. Thompson, Morsemere; N. J. A. O. Ihlseng, Joplin, Mo. Nicholas Truschkoff, Petrograd, Russia. T. Ishikawa, Japan. H. J. Wendler, Los Angeles, Cal. C. H. James, Tucson, Ariz. Ira T. Wright, Hurley, N. M. R. R. Landon, Philippine Islands. C. Yabe, Japan. Robert W. Bissell has now become associated with Gunn, Richards & Co., of New York, N. Y. Major Reginald W. Brock is giving a course in a school for commanding officers in England.

Jan 12, 1917

By W. H. Bassett

THE ease and value of the application of spectrum analysis to industrial chemistry appears to be appreciated in few of the large works laboratories of this country. For 8 years, this analysis has been of great value to the authors in both analytical and metallurgical work. To the analyst the complete qualitative analysis of an unknown alloy, revealed by a spectrogram, is a sure basis for the planning of the most direct and rapid method of attack. As the determination of each element proceeds, the purity of precipitates may be checked as often as desired. The spectrograph proves invaluable in the recognition of impurities, the separation of which would entail a lengthy and difficult procedure, or when the weight of an unknown is less than is necessary to complete the desired determinations. A few hundredths of a gram will usually suffice for spectrographic analysis. In the separation of the rarer elements, the spectrograph will show, with precision, the point where each step has been successful. In zinc of certain classes, indium, gallium, and germanium have been isolated in this way; the presence of antimony in lake coppers has been proved; and bismuth has been detected in zinc and in alloys where the presence of a few thousandths of a per cent. would be harmful. An antimony precipitate in a delicate determination may contain a considerable proportion of tin or arsenic, both of which will be revealed. The spectrograph is consequently important to the metallurgist as well as to the analyst.

Jan 2, 1922

By Sue W. Wells, James J. Moore, Stephen D. Lynch, R. Hunter White

This paper describes the products and services that Phelps Dodge Corporation desires from solvent extraction reagent suppliers and the partnering relationship that Phelps Dodge wishes to develop with these suppliers. Product topics include: 1) manufacturing concerns, 2) product and process quality control reporting and 3) reagent customizing to meet individual plant needs. Service subjects include distribution, delivery time, emergency re-supply, terms, and tailoring technical support. The partnering relationship discussion reviews mutual benefits, communications, reliability, cross-functional teams for problem solving and developing new opportunities, and long-term commitment.

Jan 1, 1994