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By R. P. Chapman

The geochemical interpretation of results of statistical analysis of published multi-element stream sediment data from southwest and northern New Brunswick is presented. Element concentrations in southwest New Brunswick are low and comparable to element concentrations in background areas in northern New Brunswick. Deposits of copper and nickel are indicated in southwest New Brunswick. Anomalous element concentrations occur in several areas in northern New Brunswick and the elements most commonly associated with these anomalies are Cu, Pb, Zn, As and Ag; and also Mo, Wand Sb. Bedrock geology greatly influences element concentrations and may cause false anomalies. Manganese has a pronounced effect on the dispersion patterns of Co and also Zn, Mo, Pb, As, Ba and Ni. Nickel and Cr are strongly sympathetically related and this association is independent of bedrock type.

Jan 1, 1977

By Adrian Dance

Newmont Mining Corporation?s Carlin (?Carlin?) operation processes roaster feed through a double rotator, dry grinding mill following secondary crushing. Metso Process Technology & Innovation (?PTI?) was involved in a review of crushing and dry grinding circuit operations in August 2009. A number of opportunities for increased throughput were identified in the PTI study. Extended plant trials were conducted in July 2010 to provide justification for possible circuit modifications and if needed, additional equipment. The trials confirmed that a finer crusher product would reduce the build-up of material ahead of the coarse grinding chamber in the double-rotator. Also revealed were material transport and airflow restrictions in the dry grinding circuit that resulted in a high circulating load. The secondary crushing plant demonstrated it was capable of reducing the amount of +¾? material in the mill feed thus increasing dry grinding throughput. However, wet and sticky feed affected screening efficiency resulting in low utilisation of the existing crusher capacity. The open circuit configuration also made it difficult to control crushing circuit product size. For the dry grinding circuit, changes in grinding media size, transfer grate design and increased airflow were recommended to reduce circulating load issues and increase circuit capacity. This paper summarises the crushing and grinding circuit review, the extended site trials performed by PTI and the improvements in dry grinding operation that resulted from this study.

Jan 1, 2012

By Yuanming Pan, Brett Rogers, Baoquan Hu, Gary Yeo, Christine Austman

The nature and distribution of radiation-induced defects (RIDs) in quartz from the Maw Zone, a yttrium- and rare-earth-element-enriched sandstone breccia complex exhibiting intense hydrothermal alteration, have been investigated by electron paramagnetic resonance (EPR) spectroscopy. EPR spectra show that detrital quartz in sandstone, from five diamond drill holes intersecting the Maw Zone and one above the crest of the so-called Quartzite Ridge, contain only background-level RIDs, indicating that Ubearing fluids were absent in this area. However, close to the sandstone-basement unconformity, in hole WR-194 immediately west of the Quartzite Ridge, the concentration of RIDs in detrital quartz is significantly above background but at least an order of magnitude lower than those at the Key Lake and McArthur River deposits. Widespread drusy quartz at the Maw Zone, which signifies intense hydrothermal alteration, is associated with hematite-, sulfide- and carbonate-bearing mineral assemblages, which exhibit complex crosscutting relationships. EPR spectra of drusy quartz in all three types of mineral assemblages are low in RIDs as well, supporting the EPR evidence that fluids at the Maw Zone did not carry significant U. These EPR results suggest that, in spite of intense hydrothermal alteration and favorable structural geology, the Maw Zone is unlikely to host any significant U mineralization. Moreover, this study shows that the EPR technique is potentially a useful exploration tool, capable of determining whether individual alteration zones in the Athabasca Basin were associated with U-bearing fluids or not.

Jan 1, 2013

By M. Reda

Inorganic oxidizing agents of the type MeOx-z such as Chromate, Vanadate, Tungstate, and Molybdate... etc. are widely used as corrosion inhibitor. In non acidic solution these oxidizing agent are reduced on the surface of the meta, according to OX + m e + p H20 Red + n OH" In which y = (n-m)/m. The purpose of this publication is to show that for many metals the value of y for any oxidizing agent determines the possibility of that oxidizing agent being an inhibitor or activator for the corrosion process. The inhibition efficiency for other ions such as Pertecnetate and Tellurate which have not been extensively studied can be predicted. A mathematical, equation was derived to express the relationship among the concentration of oxidizing agent, degree of retardation of the corrosion process I cord cor ° (ratio of corrosion current in the solution containing inhibitor to the base solution) , ionic strength of the solution and the coefficient y. The validity of y and the mathematical, equation were verified by many experimental, works on various metals such as zinc, aluminum and steel. Al, the above research works are based on the published research works of Prof. Mikhailoviskii (from 1979 til, 1998) from the Russian Academy of Science.

Jan 1, 2010

By Anthony J. Deevy

"Abstract -The Magino gold mine is located 45 km northeast of Wawa, Ontario. There was limit­ ed gold production in the Iate thirties. The present operation was officially opened in October 1988 and produced gold until September 1992. It was a 635 tonnes per day, decline-accessed mine, with ore coming from several small blast hole and shrinkage stopes.The host for the gold is the Webb Lake granodiorite stock which was intruded into the Goudreau Lake Deformation Zone. This east-northeast-striking deformation zone overprints the generally east­ west-striking isoclinally folded metavolcanic and metasedimentary rocks, which make up the east end of the Michipicoten greenstone belt. The ore-shoots are controlled by dextral delatancy associated with the Goudreau Lake Deformation Zone. Shearing, bleaching and silicification accompanied the gold emplacement."

Jan 1, 1994

By B. S. Kim, Y. D. Kim, T. S. Kim, T. B. Kim, H. J. Chae

"The Nd-Fe-B scrap was placed in Fe crucible with pure Mg in an Ar atmosphere, and the scraps were melted using an induction heating method. The effects of experimental parameters such as melting temperature (range of 993K to 1073K) and holding time (15min-600min) on the ability of extraction were investigated. The microstructure and diffusion layers were analyzed by Scanning Electron Microscopy (SEM) and Energy Dispersive Spectroscopy (EDS), and the constituent phases were characterized using XRay Diffraction (XRD). Diffusion of Nd through the Nd-Fe-B scrap into liquid Mg was described, and the diffusion coefficient of Nd in liquid Mg was estimated.INTRODUCTIONNd-Fe-B magnets are usually produced either from comminuted melt-spun ribbons as bonded magnets or hot pressed bulk magnets, or by sintering in conjunction with prior green compaction in an applied magnetic field (Sagawa et al., 1984). These magnets have been widely used for various electromechanical and electronic devices such as voice coil motors (VCMs) and magnetic resonance imaging (MRI) (Samardzija et al., 2012; Matsuura et al., 2006). The production of the Nd-Fe-B magnets is increasing by about 20% per year because of their excellent magnetic properties. However, the expansion of Nd-Fe-B magnet market induced a concern for the scarcity of Nd at the aspect of natural resource. Therefore, the development of an effective recycling process for Nd-Fe-B magnet scraps is an extremely important issue from the viewpoint of resource and energy conservation. Several recycling processes for the Nd-Fe-B magnets have been proposed (Uda et al., 2002; Lyman et al., 1993]. It has been reported that the best separation of rare-earths from the Nd-Fe-B magnets is obtained by sulfuric acid dissolution followed by precipitation of recyclable rare-earth salts. However, this process can make a large amount of waste water including dangerous solutions. Recently, (Xu et al., 2000) have reported a technique to extract Nd from 18Nd-72.4Fe-0.9B-1.82Pr-5.3Dy (wt.%) magnet scrap by using liquid metal extraction (LME) processing. However, these techniques seemed to be difficult for application, because the scraps consist of an infinitesimal amount of other minor elements (Pr, Dy, Cu, Al and Tb), and these minor elements can make a new intermetallic compounds with Mg. Also, some oxides or the plated Ni metal can be preventable to reaction between solid-liquid (S/L) interfaces. For these reasons, the substantive reaction mechanism between Mg and Nd-Fe-B scrap is not clear. In this study, the simple composition of 33Nd-66Fe-1B (wt.%) magnet scraps were prepared using an induction melting process. The effects of the experimental parameter on the diffusion properties between Mg and scraps were investigated to determine whether these methods could be used in industrial application in a liquid metal extraction (LME) process."

Jan 1, 2012

"Developing markets for western metallurgical coal have continued to stimulate considerable exploration activity in the Rocky Mountain foothills and to influence major segments of a wide-ranging carbonization R&D pro-gram. Adjunct studies have included expanded petrographie investigations.Coal preparation has• been principally directed toward utilization of prepared small coal and was, like much of the year's combustion work, strongly influenced by concern over atmospheric pollution. Particular attention has been given to desulphurization and to the suppression of pollutants in combustion systems.In the area of non-fuel utilization of coal, interest has centered on plant nutrients and on a series of coal-based carbons which, inter alia, possess utility as filtration media.Other projects included the development of improved sampling and analytical methods, investigations into the effect of storage on coal proper-ties and R&D in solids pipelining. In addition, a significant volume of basic 'uncommitted' research has been maintained."

Jan 1, 1968

By James Kear, Romain Prioul, Robert G. Jeffrey, Andrew P. Bunger, Dimitry Chuprakov

"Unconventional gas and geothermal reservoirs are typically naturally fractured and therefore the challenging problem of hydraulic fracture (HF) growth through naturally fractured rocks is an important issue especially for the development of accurate predictive HF models. This paper presents results from laboratory experiments in which HFs have been created in both sandstone and crystalline (gabbronorite) rock specimens such that they impinge either orthogonally or at an oblique angle on an unbonded, machined frictional interface. Depending on the conditions of each experiment, the fractures either cross or are blunted at the interface. The growth behavior was ascertained for these experiments based on a synthesis of the injection pressure record, active ultrasound monitoring, and direct post-experiment inspection of fractured specimens. From these experiments we observe: 1) A contrast between direct crossing and crossing with an offset for orthogonal and oblique intersection, respectively, 2) Apparent independence of crossing/blunting behavior on the friction coefficient for orthogonal intersection, 3) Dependence of the stresses required to promote crossing on the intersection angle between the HF and NF, 4) Existence of cases in which the hydraulic fracture crosses but then essentially ceases propagation such that all fluid is diverted to the interface. INTRODUCTIONHydraulic fracturing is a vital technology used to increase the productivity of oil, gas, and geothermal wells. Predicting hydraulic fracture (HF) growth is, in turn, critical to design of hydraulic fractures that grow to the desired length, accept the desired amount of proppant, and remain contained in the reservoir without unwanted height growth into surrounding layers (e.g. Economides and Nolte, 2000). The importance of HF modeling has prompted 6 decades of research during which simulators have become more efficient, more accurate, and have addressed a growing range of complexities (see review of e.g. Adachi et al., 2007).One of these complexities is the interaction between HFs and mechanical discontinuities such as natural fractures (NFs). Efforts in this area have been mainly driven by development of unconventional (i.e. low permeability) oil and gas resources because essentially all viable low permeability reservoirs, including shale gas/oil reservoirs, are naturally fractured to some degree (King, 2010). One of the most important questions for developing effective HF stimulation strategies in these reservoirs is whether the hydraulic fracture(s) is/are expected to be single-stranded or whether interaction with the NFs will lead to network-like growth. The basic building block for numerical simulators that can address this question (such as Kresse et al., 2013 and Weng et al., 2014) is whether an HF that intersects an NF will cross the NF or whether its growth will be captured by the NF so that additional fluid injection pressurizes the NF but does not generate ongoing growth of a new HF. These scenarios, including subcategories such as crossing with an offset, have been recognized for several decades (Daneshy, 1974; Warpinski and Teufel, 1987, and as recently reviewed and expanded by Chuprakov et al., 2013)."

Jan 1, 2015

By Colin E. Dunn

The high mobility of gold within the plant kingdom results in detectable accumulations of gold in many plants. Concentrations vary within individuals, among species, and with seasons. From an evaluation of the chemistry of easily acce sible organs of common pecies in the northern forests, it is concluded that alder twigs (or leaves) and conifer bark scales are the vegetation components of greatest use in the earch for concealed gold mineralization. Maximum anomaly enhancement is obtained from twigs collected in the spring. Examples are given of urvey conducted in the La Ronge Domain using 1) jack pine bark (A nglo-Rouyn and Upise Lake areas) ; 2) alder twig (McLennan Lake) ; 3) black spruce bark (Rod Zone near Mallard Lake, and at Waddy Lake) ; and 4) multi-media (Tower Lake). At the latter two sites gold-bearing till is blanketed with late glacial material. Gold enrichment in the plants suggest that the roots are ab orbing gold from the underlying till. Complex processe control the uptake and retention of gold in plants. An understanding of these processes pem1its biogeochemistry to assist in locating near- urface mineralization .

Jan 1, 1986

By E. Rosseland

Glencore Nikkelverk is operating its Chlorine Leach Process in Kristiansand, Norway, producing nickel, copper and cobalt metals by electrowinning. The copper tankhouse, with an annual capacity of 40 000 tons, is based on traditional technology with copper starting sheets and cast lead anodes. Due to the integration of this copper sulphate process in a nickel chloride refinery, operating conditions are unique. In recent years, operating costs have escalated, and health, safety and environment are top priorities. Test work on a new copper process involving permanent cathodes was therefore initiated in 2007, and a pilot plant was started up in 2012. The objective was to introduce innovative technologies and tailor these to be robust in the Nikkelverk process, to form a basis for a new sustainable copper tankhouse with a high degree of automation. Key learnings from more than 10 years of R&D work is presented, focusing on cathode materials and copper metal deposition including product quality, robotic stripping, coated titanium anodes, electrode contacts and alignment, electrode current monitoring with Hatch HELM tracker technology and acid mist capture using cell hoods with off-gas scrubbing. The new copper tankhouse project was approved in December 2018, and commissioning is planned in 2022. INTRODUCTION The Kristiansand nickel refinery was started up in 1910, processing nickel-copper matte originating from Norwegian mines. It was the first industrial plant in the world to produce nickel by electrolysis using the Hybinette electrorefining process. After roasting to burn off sulphur in the matte, copper was leached and recovered as cathodes by electrowinning with lead anodes. In the first years, the copper cathodes were fire- refined and cast into ingots for sale (Thonstad Sandvik, 2004). The Nikkelverk refinery was acquired by Falconbridge Ltd. in 1929, and since then matte from Sudbury, Canada has been the main feed source. The Hybinette process was in operation until 1975 when conversion to the newly developed Chlorine Leach Process was started (Stensholt, Zachariasen, & Lund, 1986). In this process still used today, nickel and part of the copper in the matte is leached using chlorine gas generated on dimensionally stable anodes in the nickel and cobalt electrowinning tankhouses, as illustrated in Figure 1. The presence of dissolved copper ions in the strong chloride leach solution is essential for effective chlorine absorption and nickel dissolution. To improve copper-nickel separation, slurry from the atmospheric leach is pumped to autoclaves and then to cementation tanks for precipitation of copper as copper sulphide, which is collected in filter presses. The leach residue, also containing the precious metals, goes through a 3-stage wash to remove chlorides before being introduced as a slurry to fluid-bed roasters for sulphur removal. The resulting calcine is then leached in spent electrolyte from the copper electrowinning tankhouse, to dissolve most of the copper and also some nickel, cobalt and other elements. After separation of the leach residue, elements like Bi, Te, As and Ag are removed from the strong copper sulphate solution by reaction with metallic copper in three columns in series filled with cut copper cathodes. The purified solution then passes polishing filters before being mixed with spent electrolyte and returned to the electrowinning cells.

Jan 1, 2019

By N. M. Steven, J. M. Moore, J. L. Kuyper

Abstract - Mineral exploration and research has led to the identification of four types of tungsten mineralization in the NE-trending, largely ensialic, inland branch of the late Proterozoic/early Paleozoic Pan-African Damara Orogen. The mineralization (mainly scheelite) occurs in a terrane (the Central Zone) that is characterized by multiple deformation, greenschist/amphibolite-facies metamorphism and numerous peraluminous S-type granitic and pegmatitic intrusions. The four major types of scheelite mineralization are (in ascending stratigraphie order of host rock): (1) thin (5 cm to 2 meter) quartz+ plagioclase+ diopside ± scapolite cale-silicate granofels with finely disseminated scheelite (scheelite-bearing granofels; SBG) developed as discontinuous intercalations within the cale-silicate rocks of the Khan, Spes Bona, Oberwasser and Kuiseb Formations (Nosib and Swakop Groups); garnet+ pyroxene ± vesuvianite + scheelite ± fluorite replacement skarns hosted by Okawayo, Karibib and lower Kuiseb Formation marbles in the aureoles of late tectonic, unmineralized leucogranites; metaturbidite-hosted scheelite- (and possibly wolfrarnite-) bearing tourmalinites, both stratiform and crosscutting, in the Kuiseb Formation located in the 'cleavage fronts' of late tectonic granitoids; scheelite-bearing vesuvianite +quartz+ garnet skarnoid rocks (several hundred meters in length) in the calcareous metaturbidites of the upper Kuiseb Formation. These scheelite occurrences were discovered by the follow-up of a large number of tungsten anomalies located during a regional stream sediment sampling program. Detailed mapping, ultra-violet surveys and rock sampling proved to be the most effective surface exploration techniques for locating mineralization; soil sampling and geophysics were of almost no use. The largest, continuous scheelite-bearing skarn of economic interest, Otjua, has a drill-indicated reserve of 250 000 tonnes at 0.53 wt% W03 and 8 wt% CaF2.

Jan 1, 1994

By T. G. Joseph, M. J. Bolster

ABSTRACT This paper explores passive seismic measurement as an alternative, nonintrusive approach to conducting annual brake testing on surface mine sites. Dictated by the test site location, this evaluation adhered to the brake testing procedure as per British Columbia occupational health and safety regulations. Results showed excellent correlation to those reported via conventional practice: Comparing stopping distance, time, and velocity for the proposed instantaneous passive seismic versus conventional approaches, less than a 0.5% variance was evident. A viable alternative, the passive seismic approach, allowed an entire fleet of trucks to be sequentially evaluated for annual brake testing without disrupting operations by installing mechanical testing equipment.

Jan 1, 2012

By Robert B. Parsons

"Ontario and Quebec taxpayers will have to dig deeper into their pockets to pay more tax, according to budget papers tabled in these provinces in May 1993. Individuals will be hardest hit, but corporations will also have to ante up in the face of higher rates, reduced deductions, and new taxes.Up, up, and away...Somewhere in the bleak picture of the 1993 Quebec and Ontario budgets, there is a bit of good news for the mining industry.Careful scrutiny reveals:• Ontario will correct a capital tax provision which inadvertently penalizes flow through share issuers;• Quebec's flow-through incentives will be extended to December 31, 1995; and • both Quebec and Ontario will allow deductions for mine site reclamation payments.The industry may also find some comfort in the fact that Ontario's new corporate minimum tax will be profit-based (unlike the federal minimum tax), so that non-producers should not face a liability for this tax. There is some concern though, about Quebec's announcement that the refundable credit mechanism in the Mining Duties Act will be reviewed."

Jan 1, 1993

By William E. Roscoe

"Valuation methods are well established for mineral properties with production or imminent production, and include discounted cash flow and comparable transactions. Valuation methods for non-producing mineral properties, however, are more subjective. Non-producing mineral properties include those at various stages of exploration, properties at the prefeasibility or feasibility stage, properties with currently uneconomic mineral resources, and past-producers. Different valuation methods may be appropriate for different types of mineral properties.Income approach methods such as discounted cash flow and option pricing are generally not applicable to properties at the exploration stage. The market approach is generally appropriate to all types of mineral properties, although it is difficult to find good comparables because of the unique nature of mineral properties and the small number of transactions. Cost approach methods, such as appraised value and geoscience factor, are commonly used for exploration stage properties.Canadian standards and guidelines for valuation of mineral properties are in the process of being finalized by a Special Committee of the Canadian Institute of Mining, Metallurgy and Petroleum (CIMVal Committee). The CIMVal Standards are intended to be consistent with National Instrument 43-101, which sets regulatory standards of disclosure for mineral projects, and with International Valuation Standards. The intent of the CIMVal Standards and Guidelines is that mineral property valuation be carried out by appropriately qualified individuals and that all relevant information be disclosed."

Jan 1, 2003

By U. Storck

"Shaft sinking for exploitation of the deep potash beds in Saskatchewan involved great difficulties from the very first because of the need to exclude from the shaft the high-pressure water encountered in the overburden. Control of the troublesome Blairmore quicksands was achieved relatively quickly by use of the freezing method and by lining with cast iron tubbing. The unsolved problem remained, however, of sealing the water-bearing Devonian where the formations had extremely low permeability and were thus hard to grout. Long experience in German potash mines had shown that the permanency of the whole mine would be seriously endangered if large amounts of unsaturated salt water were allowed to flow in from the shaft wall and merely removed by pumping. The prevention of water movement and the resulting dissolution of salt in the overburden were known to be most important. In the Alwinsal shaft, water flow from the Devonian has been prevented by the use of a steel and concrete sandwich lining similar in principle to a kind of lining introduced a few years earlier, and for another reason, in German coal shafts. As its installation is neither more expensive nor more time consuming than that of cast iron tubbing lining, this same lining was also chosen as protection against the Blairmore quicksands. The great advantage of the steel lining, in addition to its relatively high strength, is the fact that it is possible to make the joints of the individual segments absolutely and permanently water-tight by means of tested welds. The virtual dryness of the Alwinsal shaft will also result in lower costs because significant corrosion of all its steel installations, including skips, cage and ropes, will be prevented."

Jan 1, 1968

By R. P. D. Graham

It is almost exactly two hundred years since the foundations of the mining and metallurgical industries in Canada were laid. There '."'as nothing spectacular about this early start. It had to do with the most basic phases of these industries-the mining of coal and iron ore, and the manufacture of cast and wrought iron. At several points along the coast of Cape Breton island, coal seams may be seen outcropping quite conspicuously, and it is probable that they had been observed, and possibly worked in a small way, in very early times. However that may be, these coal seams have the distinction of being the first in North America of which there is any printed record, reference to them appearing in a volume by Nicolas Denys which was published in Paris in 1672. Regular coal mining in the district did not commence until about fifty years later, however. The metallurgists started their operations along the north shore of the St. Lawrence river. Here, at many points between Montreal and Quebec, are to be found deposits of bog iron ore, and in 1 730 a furnace for smelting such ore was established on the St. Maurice river. The St. Maurice forges continued in operation until 1880, and throughout that long period they were famed for the fine quality of castings produced, and also for a-superior wrought iron.

Jan 1, 1924

By D J. McDougall

Due to changes in the solid-state conditions of minerals in the rocks surrounding hydrothermal, contact meta-somatic or metamorphosed ore deposits, positive or negative thermoluminescent anomalies may be found in their vicinity. Several types of equipment which can be used for both quantitative and semi-quantitative measurements of the emission are discussed and compared. Methods of selecting, preparing and testing samples to ensure reproducible results are outlined, along with the kind of data which can be obtained from different types of equipment. The normal thermoluminescence of rock-forming min~ erals in the common rock types is noted, and variations in the solid-state conditions in the wall rocks which will cause marked increases or decreases of true thermoluminescence are outlined, as well as the thermolum-nescence-like emissions which are present in the vicinity of ore deposits. Introduction T HERMOLUMINESCENCE occurs when certain crystalline materials are heated to temperatures ranging between 180' and 400°C. The light emission can be ascribed to the release of electrons metastably trapped within the crystal lattice, with peak emissions taking place at temperatures which are more or less specific for a particular set of traps; the area under

Jan 1, 1965

By E. J. Sides

In this paper, the argument is put forth that the codes used for public reporting of mineral resources and mineral reserves have some significant limitations with regard to the information provided to investors on the short- to medium-term value of mining properties. Such limitations include a) failure to explicitly incorporate a time element and b) failure to state explicitly the quantity and quality of mineral product that will be produced for sale. A time-value framework for reporting mineral assets is proposed in order to overcome these limitations. The proposed system is based on two classification axes: a) an X-axis representing time in years during which the value of the asset is likely to be realized and b) a Y-axis representing the value identified by a mining or exploration company\u2019s activities. The potential benefits of this system are discussed, including the ability to incorporate factors, such as permitting and construction times, directly into the magnitude of the reported mineral assets. The proposed framework would assist in the standardization of mineral assets reporting in such a manner that they could eventually be more readily included in financial statements. Year of Publication: Not explicitly mentioned in the document.

Jan 1, 2010

By B. R. MacKay

Introduction Of all Canada's mineral resources, its coal deposits have probably received the most continued attention by the Geological Survey since its inception ninety years ago. A casual review of the many geological maps of coal areas by the Geological Survey will show how geological and topographical detail on the maps has gradually increased to meet the ever urgent demands of the mining industry. In the early stages of exploration, the mapping done, especially in the coalfields of the Rocky mountains, was largely of a reconnaissance nature. On these maps the topographical relief, where shown, is indicated by form lines or by hachures, the boundaries of the coal-bearing formations are only approximately defined, and the geological structure of the coal seams is illustrated by one or more generalized cross-sections. Once mining development on a coal area began, there arose a demand for more detailed maps. To meet this need, topographical and geological maps on a scale of one inch to a mile were made, in which the ?topographical relief is shown by contour lines having generally an interval of 100 or 200feet. On the geological maps, the boundaries of the formations are accurately delineated, and the geological structure of the area is illustrated by one or more structure sections drawn across the area, which show the position and attitude of fault lines, the crests and troughs of folds, and the attitude of the various formations (See maps of Costigan Coal Field, 1905, and Cascade Coal Basin, 1907, by D. B. Dowling).

Jan 1, 1932

By Seshadri Seetharaman, Nurni N. Viswanathan, Haijuan Wang

The present work aims at some process modifications in specified metallurgical processes, wherein CO2 can be used successfully as an oxidant for decarburization in steelmaking and applied in some non-ferrous metals production processes. During the decarburization of Cr-containing high alloyed steels, the present researchers investigated the possible use of CO2 instead of Ar-O2 mixture and could successfully decarburize the steel melt without significant loss of alloyed Cr to the slag phase. A mathematical model was developed based on the bubble formation accompanying the chemical reaction: C(molten steel)+ CO2(gas)= 2 CO(gas). The model predictions were tested by laboratory scale (1 kg) experiments carried out in an induction furnace and very good agreement between the model predictions and experimental results were observed. A national project has been sanctioned in China for the implementation of CO2 in decarburization of ferroalloys as well enable the addition of pig iron in the electric arc furnace process when the scrap supply is limited. New processes have been developed for the utilization of CO2 in the case of non-ferrous processes. A novel method of treatment of Al dross by leaching with water and capturing the evolved NH3(formed by the hydrolysis of AlN) has shown very promising results.

Jan 1, 2015