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By Jean Scott, G. A. Collins, G. W. Hodgson

WHILE it is well known that trace metals in crude •oils and distillates have been a matter of deep concern to refining engineers because of the damage done .by the metals to cracking catalysts and refractories (8, 5), the trace metals in crude oils may be of great benefit in correlation studies and in origin studies. During the geological processes in which the oil is formed from •animal and vegetable life, the hydrocarbons are subjected to a host of inter-related reactions, both physical and chemical. It has been well demonstrated that the lighter materials, certainly the short-chain paraffin hydrocarbons, are degradation products of the heavier molecules, and it might be concluded that for correlation studies it would be advisable to direct attention as much as possible not to the degradation products of the large molecules but to the large molecules themselves. Be this as it may, the methods at •hand to conduct the study are not particularly precise and, in the past, attention has centred on the simpler small molecules, as evidenced by the great mass of work involving distillation and chromatography with painstaking separation of the simpler 'front-end' hydrocarbons.

Jan 1, 1954

By K. Ohto, B. B. Acihikari, H. Kawakita, M. Gurung, S. Alam

Two kinds of adsorbents were prepared from persimmon tannin extract to investigate their adsorption behavior of metal ions from hydrochloric acid solution; one was prepared by treating with concentrated sulfuric acid while another was prepared by immobilizing functional groups of quaternary amine. The former adsorbed only gold(III) and its maximum adsorption capacities was evaluated as high as 1510 g/kg while the latter adsorbed not only gold(III) but also palladium(II) and platinum(IV), the maximum adsorption capacities of which were evaluated as 820, 89 and 101 g/kg, respectively. For both adsorbents, practical adsorption of base metals was not observed.

Jan 1, 2011

By D. F. Lillie

The milling plant of Bicroft Uranium Mines Limited has been in operation for a period of 2 years. During this time many changes, both physical and chemical, have been made in an effort to improve plant efficiency. Investigational work has been facilitated greatly by the fact that the Bicroft mill consists to a large extent of two parallel circuits; however, the number of inter-related variables is great, and it is difficult to measure, let alone control, all of them simultaneously. The Bicroft mill staff feel that much progress has been made, but there is much yet to be done and many questions still to be answered. The property of Bicroft Uranium Mines is located in Cardiff Township in the Highlands of Haliburton County, southeastern Ontario, some 140 miles northeast of the city of Toronto and 70 miles due north of Lake Ontario. The ore-bearing dikes are classed as mafic, non-segregated, syenite and granite pegmatites. Microline, microline perthite, quartz, uraninite, uranotharite, fluorite, titanite, cyrolite, calcite, pyrite, pyrrhotite and molybdenite as important accessories. The mill was designed for a nominal capacity of 1,000 tpd with all sections except grinding, leaching and clarification capable of 1,500 tons. Feed was entered to one mill unit on October 29, 1956 and to the second parallel line on November 13. The total feed rate was at 1,000 tpd on November 15. The first precipitate was produced on November 12. By August 1958 the average entry had been increased to 1,410 tpd without the installation of any additional major equipment. The overall recovery has been greater than 93,0 pet do several months, but a recovery of 92.5 pct appears to be most economical. Operating time for 8 months in 1958 has been 97.1 pet although all grinding mills were relined during this period.

Jan 1, 1959

By Mei Yang, Wei Gao, Jian Yang, Qingcai Liu, Wenchang Xi

"TiO2 has been loaded on cordierite porous ceramic to prepare the SCR catalyst carrier by using both APCVD and sol-gel technology. In APCVD method, TiC14 and O 2 were used as reaction precursor. TiC14 was gasified by using N2 as carrier gas which was controlled to 500sccm. Its reaction temperature and reaction time were limited to 773K and 30min respectively. The physical properties, SEM and SEM-EDX of the TiO2-cordierite carrier and the properties of SCR catalysts prepared by these carriers have been tested. The tests showed that TiO2 loaded by APCVD method were of graininess shape and even accumulation. The loading rate of TiO2 and the specific area of carrier sample were increased 114% and 21 % respectively comparing with sol-gel technology. In the result of sol-gel method, the maximal difference of Ti content was 66.92%, while the result of APCVD method was 18.89%. It demonstrated that TiO2 was uniformly attached with the cordierite ceramic by using APCVD method, which would ensure more active ingredients well loaded on the Ti02-cordierite carrier. This difference made the denitrification ratio of catalyst prepared by APCVD method was 8.1 % higher than that of catalyst prepared by sol-gel method.IntroductionIn recent years, the emission of NOx, which were caused by coal-fired power plants, has gotten more and more attention. SCR (selective catalytic reduction) is the most effective technology to DeNOx [ll. The core technology of it is the catalyst. The SCR catalyst usually uses Ti02 as the carrier, and V2O 5 as the active component [2, 3] . However, the thermal stability and mechanical properties of TiO2 carrier are unstable, which would influence the performances of the catalyst. The commercial catalyst generally uses WO3 or MoO3 to promote its heat stability at present [4-7] Besides, TiO2 is expensive. Compared with TiO2, the cordierite is of good thermal stability and lower price. So loading Ti02 on cordierite porous ceramic as carrier to produce SCR catalyst is of good prospects [S, 91 • Currently, TiO2 is usually loaded on cordierite by the sol-gel method. But some research has shown that the sol-gel method easily reduced the loading performances of TiO2, such as distribution, combination, etc. APCVD (atmospheric pressure chemical vapor deposition) has many advantages to preparing TiO2 films, such as high bonding strength, fast reaction rate and so on [l0-13l_ In this paper, TiO2 has been loaded on cordierite porous ceramic to prepare the SCR catalyst carrier by using both APCVD and sol-gel methods. The properties of the carriers prepared by the two processes have also been compared."

Jan 1, 2011

By M. Nzotta, L. Teng, S. Seetharaman, A. Chychko

The objective of the present work is to optimize the EAF practice towards Mo alloying with maximum retention of the alloying element in molten steel. During Mo additions, there were significant losses to the dust (ca 7 %) and to the slag phase (ca 2 %), which had serious economic and environmental impacts. The present work was aimed at designing a suitable Mo precursor, an alternative to ferromolybdenum, as the Mo source and a process sequence for optimal retention of Mo in the steel. The design of the Mo source should be in such a way that low cost raw materials such as MoO3 concentrate have to be used, stable during the addition so that the vapour phase losses as MoO3 are kept minimum and the dissolution of the precursor in molten steel is easy without loss to the slag phase. After thermodynamic considerations, three precursor materials were chosen, viz. CaMoO4, MgMoO4 and Fe2MoO4. Synthetic mixtures of the component oxides in each case as well as pure MoO3 were investigated by TGA and high temperature XRD in order to find out the temperature range in which the compounds were formed. Experiments were also conducted separately where the evolved gases were analyzed. All the three precursors were formed easily and the loss of MoO3 to the vapour phase was found to be extremely low. Addition of the oxide mixtures to steel melts were conducted in three different scales, viz. 16 g, 500 g and 3 tons (induction furnacle). Initial experiments showed that MgMoO4 was not suitable since the Mo yield in the steel melt was not very high. Fe2MoO4 was found to perform best, the Mo yield reaching 98 %. Further trials were conducted in the 65 ton Electric Arc Furnace (EAF) at Uddeholms AB in Hagfors. Mixtures of mill scale, MoO3 and carbon in suitable proportions were added in a pre-determined addition sequence. It was found that, in the actual practice, the Mo yield reached 99 %, equaling in performance the addition of ferromolybdenum. The process offers an effective use of cheaper raw materials and very high Mo yield avoiding a pre-treatment step like the production of ferromolybdenum. This is both cost effective and environmentally advantageous. The process has been patented and is being currently implemented at Uddeholms AB, Hagfors, Sweden.

Jan 1, 2011

By J. C. Murray

Introductory: In dealing with a topic so large, one that involves such a multiplicity of details, and that also has certain controversial aspects, it is quite impracticable within the limits of this article to touch upon many most interesting phases and incidents. Also, to bring out the actual truth, it is necessary to make certain categorical statements. The writer believes that all such statements made here-under are supported by facts. Again, however, it is out of the question to cite all the proof. The writer, therefore, will gladly answer any pertinent criticisms or questions and thus supplement the unavoidable brevity of this paper. Controversial points will take care of themselves. Historical: For present purposes the history of gold mining in Nova Scotia may best be summed up in a very few paragraphs, in some of which the writer quotes freely from recent reports compiled by himself. The first material discovery of gold was made in the year 1860. As this and rapidly succeeding discoveries were looked upon as bonanzas, the claims were fixed at a size of 20 by 50 feet, and a yearly rental of $20 was charged. Later the claims (areas) were increased in size to 50 by 150 feet. In the year 1866 a temporarily successful company, so we are informed by a contemporary writer, owned a mill and mining plant worth $6,000. As this fact is cited with admiration, it is apparent that most of the mining and milling must have been done in a very primitive manner indeed.

Jan 1, 1926

This paper deals with the evolution of Canadian shaft sinking technology over the last 15 years. Most, if not all, shaft excavation projects in Canada prior to 1990 were sunk using traditional benching methods with labour intensive equipment. In the late-1980s, J S Redpath Limited of North Bay, Ontario, Canada, were contracted to deepen the shaft at Atomic Energy of Canada LimitedÆs Underground Research Laboratory (URL) located in southern Manitoba. The laboratoryÆs role was underground hydrological and geomechanical research, so the project offered both time and opportunity to conduct additional experiments while sinking. The offshoot of the research program was the true birth of the Canadian version of full-face, long round shaft sinking technology. Throughout the 1990s, this sinking method has been further refined over a number of shafts. The results have been faster sinking rates, a safer work environment and an overall improvement in project economics.

Jan 1, 2002

By Seung-Kyu Son, Michael T. Chandler, Youngtak Ko, Gyuha Hwang

Over the past decade, sea-floor hydrothermal vent fields have been studied by many researchers because of their commercial potential of mineral resources and the origins of Earth’s life. Approximately 300 of these are reported as massive sulfide deposits near the mid-ocean ridge, most of which are located in the Atlantic and Pacific ridges. However, only fourteen deposits have been identified in the Indian mid-ocean ridges. The Central Indian Ridge (CIR) between 8°S and 12°S is composed of three segments with a slow full- spreading rate of 33-37 mm/yr. The hydrothermal activity at the slow-spreading center can be generated along the ridge axis attended by volcanism or along the tectonic features, such as oceanic core complexes (OCCs). OCC is an exposed mantle rocks composed of peridotite and ultramafic rocks uplifted through long-lived detachment fault processes which can also lead to extensive hydrothermal circulation near the slow-spreading center. Therefore, the identification of OCC’s properties will be an important indicator for finding the sea-floor hydrothermal vents. To study hydrothermal activity of the CIR, Korea Institute of Ocean Science and Technology (KIOST) have conducted expeditions using R/V Onnuri over four years (2009-2011, 2017). High-resolution bathymetry and backscatter data was obtained during expeditions using multibeam echo system of EM120 in 2009-2011 and deep-tow side-scan sonar system of IMI-30, which has more higher resolution than EM120, in 2017. In this study, we use these high-quality data for constraining location and size of OCC. We also analyze the geophysical and morphotectonic characteristics of OCC gathering high-resolution bathymetric map and backscatter image.

Jan 1, 2018

By Thomas E. Shufflebarger

Definition of glass sand prospects may be modified by constraints which range from demography to critically important product-control. Characteristics of usable raw materials, physical and chemical, are discussed; an ideal raw material is defined. Following field investigations and preliminary sampling, evaluation of selected prospects includes use of modern drilling techniques, viz.: core, percussion (air-hammer), auger, jet, rotary jet, split-spoon and other. Nearly complete core (sample) return is mandatory. Land-use regulations, availability of water and transportation continue to direct exploration in a major sense. But fitting a prospect to burdensome politics nay be considered a decidedly negative factor.

Jan 1, 1983

By R. D. Brown

"""A matter of serious concern to the mining industry in British Columbia""; this comment reflects the attitude of the Mining Association of British Columbia toward the proposed new B.C. Mineral Royalties Act. The proposed legislation, introduced by the provincial government in February and now being debated by the legislature, combines a basic 5% royalty on the selling price, less approved p1ocessing and transpo1•tation costs, of minerals produced in B.C. with an ""excess"" royalty of 50% of any price increases over a predetetmined base. Government estimates project annual revenues of $20 million from the new royalty structure. The accuracy of these figures has been contested by the mining industry. Based on current world prices for copper the industry estimates that the provincial revenues from this mineral alone may run as high as $140 million in 1974 and $150 million in 1975. The Mining Association has warned that the new royalties “threaten to become confiscatory""."

Jan 1, 1974

By Paul Hett

The much-heralded Deep Ruth operation of Kennecott Copper Corp., at Ruth, Nev., is scheduled to become a producer by 1957. Inaugurated as a project in 1951, production was originally scheduled to start in 1953, but excessive water hindered shaft sinking. A revised schedule called for output by 1955, but again plans had to be changed. This time the change was to permit mining of an orebody that would have otherwise been lost because of block caving methods planned for the main deposit. The new ore is within the cave limits of the larger orebody, above the first production level. Ore will start coming from this new source in 1956, a year ahead of the principal operation. (See NEWS, page 344.) There is little doubt that current economic conditions and unforeseen expenditures for early shaft development will make the Deep Ruth a high-cost producer. Yet, some of the drawbacks of the Kennecott operation may be mitigated by the possibility that additional exploration will increase the already assured 25 million tons of 0.83 pet copper ore. While Kennecott is missing out on the current high copper market and is thus left with a potentially narrowed profit, the predicted demand for copper has created an optimistic feeling. Its development is certain to enlarge known U. S. copper reserves and significantly extend the life of Kennecott's Nevada operations.

Jan 4, 1955

By Chi-Yuen Wang, Chaw-Long Chu

The time-dependent volumetric constitutive relation for a San Andreas fault gouge and a consolidated kaolinite are experimentally determined at confining pressures to 200 Mpa, under creep condition and at ultrasonic frequency. At any given pressure, the bulk modulus determined at 1 Mhz frequency is identical to the "elastic" modulus determined at a stepwise change of pressure. After the pressure change, there occur a time-dependent change of volume and thus the effective bulk modulus. The constitutive relations may be modeled by a standard linear viscoelastic medium with pressure-dependent moduli and viscosity. For the San Andreas fault gouge, viscosity increases from 2x10 13 poise, at 17 Mpa, and 10 14 poise, at 100 Mpa. For kaolinite sample, the corresponding values are 3x10 12 poise and 10 13 poise. These results imply that both stress and pore pressure in fault zones may show time-dependent variations in response to a change of state of stress, such as that occurring after an earthquake.

Jan 1, 1982

By R. L. Vaughn, A. G. Moon

In 1972 a major renovation of the flotation and regrinding circuits was completed at Kennecott Copper Corporation's Chino Mines Division concentrator at Hurley, New Mexico. At that time a new lime distribution and control system was placed in operation. Lime is used to depress pyrite, and flotation at a high pH or alkalinity is required for optimum recovery of principal copper minerals, chalcopyrite and chalcocite with good rejection of the pyrite. Regrinding is also required to liberate chalcocite, much of which occurs as intimately associated chalcocite-pyrite middling grains. Accurate control of the lime addition is necessary to obtain both optimum metallurgy and minimum lime usage. At low pH levels, flotation cell control is difficult due to excess froth, but excessively high pH levels can go unnoticed because froth characteristics do not change from those experienced at the desired pH. With manual control of the lime addition, the desired pH can be exceeded for periods of up to two hours. Test Work Plant test work on a lime control system using conventional pH probes gave disappointing results with high electrode maintenance and poor control characteristics. For example, the rougher flotation cells are operated at a pH between 11.4 and 11.6 and the probes required cleaning at least once a day, and occasionally every shift. These high maintenance requirements were considered unreasonable for a plant-wide system using six or more control loops.

Jan 1, 1979

By H. B. Farnam

"THE IRON ORE Company of Canada has been using do-it-yourself type explosives for three years. During the last 12 months we have used over 10 million pounds of ammonium nitrate-fuel oil explosives and either purchased or formulated one million pounds of slurried explosives.W e have been moving approximately one million cubic yards of stripping and ore per month and we expect our production rate to in-crease. Eighty per cent of our strip-ping and ore is soft enough to be blasted successfully with ammonium nitrate-fuel oil mixtures. Twenty per cent of our material is extremely hard and requires an explosive having greater strength than an AN-fuel oil mixture.W e had been using canned am-monium nitrate base explosives and TNT pellets to give maximum bottom loading density to fracture hard rock. As AN -fuel oil became widely used, it was apparent that other types of explosives could be formulated to fit our blasting requirements. Dr. M. A. Cook of the University of Utah was consulted regarding new explosives and together we developed the blasting slurries.Figure 1 shows a general view of one of our hard rock pits. The foot wall is on the right-hand side and this material is called iron forma-Figure 1.-General view of hard rock pitstion by our Company but is called 'Taconite by the operators on the Mesabi Range. This material runs 35 to 45 per cent iron and many pieces are hard enough to scratch glass. The formation is tilted at an angle of 55 degrees as can be seen in Figure 3.The bedding planes of this rock are about 24 to 36 inches apart and if the material is not well broken or fragmented, large chunks or slabs must be handled by the shovels which reduces shovel capacity and efficiency and increases maintenance costs."

Jan 1, 1960

By A. Dolatmoradi

Nanocrystalline structure formations produced by severe plastic deformation in Fe-0.15C with initial ferritic-pearlitic and IF steel with ferritic microstructures have been studied through microstructural observation and microhardness measurements. It was found that the nanocrystalline region first forms near the surface of samples due to localized severe deformation. It was also observed that the nanocrystallization rate of Fe-0.15C and IF steels and the deformed layer thickness in these two materials are different with similar milling conditions. The crystallite size and structural evolution of the samples during milling was studied by employing XRD and SEM.

Jan 1, 2010

By D. Adiguzel

In this research, providing the sustainability of production quality was aimed for a quarry which is located in Istanbul western part of Turkey and producing concrete aggregates with different types of rock. First, research field was divided in 3 different areas in accordance with the geological differences and parameters that control their product quality, limit values of standards and effect levels were determined. Concrete aggregate conformity tests which are stated in international standards were applied on samples which were taken from these 3 different areas and physical, geometric and chemical properties of each rock type were revealed. The properties of the 3 different types of rock which were produced in the quary were determined and the binary blends were composed. Blending studies were conducted with linear programming technique. In the linear programming model, the cost of aggregate production was aimed to be minimal. The limit values that meet literature and national standards for usability of aggregates in concrete were defined as constraints in the linear programming model and evaluated with objective functions, thus the most suitable aggregate blends were composed. In conclusion, to provide the sustainability of product quality, the most appropriate product blends were composed for the research field and the usability of this model for those quarries were revealed.

Aug 1, 2013

By V. Rastogi

Surfactant-based bactericides are able to control acid formation in sulfidic materials such as pyrite and sulfidic ores, thereby helping to abate acid rock drainage. Bactericides are used in the following two ways: as periodic or continuous spray treatments for the prevention of acidification of material actively handled and moved and in controlled-release form for reclamation. Site-specific bactericide treatments are designed for active sites and reclamation. Results from two active coal refuse sites show that acid production can be reduced by 88% or more. Results from reclaimed sites show that bactericide treatment can be more effective than the addition of alkaline materials such as limestone and can reduce acid production from 3,500 to <30 ppm. The controlled-release-pellets treatment outlasts the life of the pellets, as shown by a study of a site now 10 years old A single treatment sets up a change in site microbiology to replace acid-producing Thiobacillus ferrooxidans bacteria with heterotrophic bacteria and creates a stable site without the need for further treatments. A secondary beneficial effect of bactericides is on revegetation, and biomass from treated areas is almost 10 times that from areas not treated with bactericide. Depending on the application, bactericide treatment can be cost effective upfront and certainly long-term, compared to the perpetual water treatment that could be required, even after productive use of the site is completed

Jan 1, 1997

By Pedro Cunha Alves, Wagner Viana Bielefeldt, Vinicius Cardoso da Rocha, Augusto Lachini Pereira, Julio Aníbal Morales Pereira

The capacity of steelmaking slags (CaO-SiO2-Al2O3-MgO) on inclusion removal from liquid steel was investigated through experimental conditions. Laboratory experiments with slag and steel samples (with inclusion population known) were performed using a vertical electric resistance furnace at 1600 ºC. After the melting experiments, slag and steel samples were separated and analyzed regarding their chemical composition and inclusion population evolution. The capacity of slags on inclusion removal was evaluated based on the thermodynamics (solid and liquid phases proportion, phase composition and effective viscosity of slags) calculated using the FactSageTM 7.2. Results indicated that changes in the composition of slags (regarding CaO/SiO2 e Al2O3) presented effects on the steel cleanliness. The total inclusion density decreased in all steel samples and the removal of inclusions by slags shows a tendency to improve as their viscosity decreases (< 0.23 Pa.s).

Oct 1, 2019

By Herbert Haas

CHEAP power is essential to large-scale mining and metallurgical operations, particularly where fine grinding of large tonnages has to be resorted to, as is the case with an increasing number of. mines treating disseminated copper ores, or low-grade gold ores, in the grinding of which considerable power is consumed. A comparison of the cost of generating power with Diesel engines and steam turbines and a brief discussion of the different factors governing the profitable use of either type of prime mover may be timely in view of the importance of. a cheap supply of power to the mining industry, and the prominence that has lately been given to Diesel engines in America. As many of our most important mines and largest producers of metals are located in sections where neither cheap coal nor water power is available, and the price of oil fuel is increased by long hauls, the Diesel. engine will. become a prime mover of increasing importance. This applies particularly to the Southwestern States, where an ample supply of cold water for condensing purposes is unusual and local climatological conditions interfere in securing the high vacua essential to high turbine efficiency. About 12 times as much water will be required for condensing purposes with steam turbines under general conditions as is needed for jacket-cooling of two-stroke, cycle Diesel engine; four-stroke cycle Diesel engines require only one-twentieth of the cooling water. Another condition favoring the use of Diesel engines is the high load factor at which most mine power plants operate. The influence of load factor on the cost of generating power is shown in Tables 1 and 2 and in Fig. 1.

Jan 7, 1916

By S. Marion Tucker

THE aggregate number of "papers" read within any one year before more or less bored and bewildered audiences is simply appalling. We have seventy to eighty engineering societies alone, not to speak of the many hundreds of societies of every other imaginable kind. And each meets at least once a year to tell what it has found out since the last meeting. All this is very fine and fortunate, at least in the case of the scientific and technological societies; for if even only one significant discovery, one new truth, one new idea comes out at the meeting, the session has been abundantly justified. To many of us, not scientists or technologists, the scientific and technological societies seem to release by far the most useful and important information. What they have to say is often of prime importance directly to human life and to industry, and is perhaps even more important indirectly in its final influence upon social and economic conditions, thus ultimately determining the course of what we like to call civilization. The paper read by that quiet, unpretentious man on the platform ma; mean the revolutionizing of a great existing industry, the creation of an entirely new industry, the gain of millions of dollars to some persons, the loss of millions to others. But, lamentably,

Jan 1, 1940