Search Documents

By T. S. Smith

INTRODUCTION IN PREPARING this paper for the District 4 Meeting, three factors had to be considered. First, the paper must fit the time alloted; second, it must give a general picture of the geology for those unfamiliar with the property; and third, it must contain some new material in order to be of interest to local delegates. The most comprehensive extant discussion of the geology of the property of McKenzie Red Lake Gold Mines, Limited, is contained in Horwood's report on the general Red Lake area ( 1). This report is the 'bible' of the area, and a general paper on the geology of this particular mine would almost certainly appear to be a condensation of it. It was thought, therefore, that the most suitable procedure would be to base the general outline on Horwood' s report, to extend that outline where possible from information gained since its publication, and finally to leave dangling for the contemplative geologist some of the ideas and problems which ?are currently under consideration. LOCATION AND HISTORY The property of McKenzie Red Lake Gold Mines, Limited, is in Dome township, in the Red Lake mining division of northwestern Ontario. The mine is on McKenzie Island, about four miles north, by water, of the Hasaga mine and old Howey mine.

Jan 1, 1951

By F. Ajersch, A. R. Hekmat

Apparent viscosities of hypo-eutectic (Al-7% Al) and hyper-eutectic (Al-35% Si) binary alloys were measured in the semi-solid state using a Couette type viscometer at variable shear rates. Analysis of the microstructural evolution demonstrates the differences in the rate and degree of attrition of the primary phase particles which are characteristic of the thixotropic nature of the semi-solid alloy. It was observed that the Si primary phase in the hyper-eutectic alloy is much more difficult to fragment than the dendritic a-Al phase in the hypo-eutectic alloy. For the case of the a-Al, the dendritic structure is broken down by attrition and fracture of the dendrite arms whereas the fracture of the Si hexagonal crystals in the hypereutectic alloy occurs along the {100} and {110} cleavage planes. Results are presented for fixed solid fractions of the primary phase at isotherm condition for each type of alloy.

Jan 1, 2006

By F. G. Vetsch, F. A. Ronaghan

"Introduction1N THE FALL of 1951, Peace River Allied Fort St. John No. 1 well was drilled in Lsd. 1, Section 9 Township 83, Range 18, West of the 6th Meridian, on the flats of the north side of Peace river, six miles southeast of the village of Fort St. John, B.C. During this operation, non-commercial shows gas in three zones and of oil in one zone were obtained during the drill-stem tests. Further geological study indicated that this well was on the southeastern edge of the Fort St. St. John structure.Pacific Fort St. John No. 4, drilled shortly afterwards, obtained possible commercial gas flows on drill-stem test in five zones and thus encouraged development of what has become Canada's largest multizone gas field.In general, the productive horizons in this area possess fair per-meabilities and high porosities, a combination which provides for high reserves and moderate productivities. Development to date has therefore stressed experimental techniques in drilling and completion practice to provide high deliverability wells.Data and information of a specific nature apply, in all cases, to the pools in the Fort St. John structure."

Jan 1, 1954

By R. A. L. Drew, G. Mendoza-Suarez, J. Filipi, R. Vintila, J. A. Kozinski

Economics and environmental considerations along with the increasing demand of hydrogen encourage development of novel technologies such as plasma processing of hydrocarbons and thermal cracking of natural gas. Plasma discharges, either in thermal or non-thermal regimes are expected to allow low temperature and fuel flexible on-site hydrogen generation. The main drawback of thermal plasma reformers is the high-energy consumption resulting from high-temperature operation. On the other hand, non-thermal plasma, generated by dielectric barrier discharge (DBD), is able to simulate the chemical reactions employing much lower energies than those required by thermal treatment processes. The non-thermal plasma process allows for instance, a direct conversion of methane into hydrogen and carbon black with no CO2 release. The focus of this research was on the GHG-free method of H2 generation in compact non-thermal plasma reactors using low, medium and high permittivity dielectric ceramics. A stable, non-thermal plasma was generated by placing a dielectric ceramic between two electrodes with a 25 thou gap and applying an alternating current of 1-5kHz and voltages of 4-8kV. In order to ensure energetic efficient plasmas, experiments were conducted to analyze the behaviour of different permittivity ceramics. It was found that the dielectric properties of a ceramic, when used in a DBD reactor, have a strong influence on the discharge characteristics, which in turn influence the power consumption. Higher dielectric constant resulted in higher conversion rates of methane (higher yield of hydrogen and carbon). At the same time, the mechanical properties of the dielectric material, which are closely associated with its processability, influenced its resistance to electron bombardment, as well as thermal and mechanical damage. Therefore a reliable ceramic should have good dielectric properties, in addition to good thermo-mechanical stability.

Jan 1, 2004

By Paul W. Kingston

In New Brunswick, during the 1970's, rocks of the Lower Carboniferous Windsor Group in the Moncton Basin of the Fundy Epieugeosyncline have been the target of intense exploration and drilling programs. Sylvinite ore was discovered in three structural basins of the Moncton Basin near Sussex through a drilling program sponsored jointly by the Federal Department of Regional Economic Expansion and the New Brunswick Department of Natural Resources. In 1973, exploration and development rights to the western end of the Moncton Basin were awarded to the Potash Company of America. One high-grade sylvinite unit, varying between 15 and 70feet in true thickness, with a strike length in excess of 5 miles, is located near the stratigraphic top of the assymetric, semi-diapiric, locally overturned anticline. Late in 1975, exploration and development rights to the Marchbank Syncline were awarded to International Minerals and Chemical Corporation (Canada) Limited. To date, a stratigraphic evaporite sequence, forming the semi-diapiric core of the syncline, has been shown to contain one major high-grade sylvinite unit averaging 70 feet in true thickness over a strike length in excess of 2 miles. Both properties appear to have potential considerably in excess of that revealed by the exploratory drilling, and both, because of numerous mineralogical, structural and stratigraphic similarities, are thought to be depositionally contemporaneous. Both potash deposits lie within 50 miles of the Saint John all-weather deepwater port, thus affording easy access to eastern and mid-western U.S. markets. Further opportunities for potash exploration in New Brunswick are considered excellent, as there are large untested areas with favourable geology and known potassium water anomalies and negative gravity anomalies occurring in the Moncton and Cumberland basins, and in the Central Basin of New Brunswick.

Jan 1, 1979

By M. Dupuis

In the present study, the heat balance of the Hirakud smelter aluminium reduction cell has been accurately assessed using only a surface thermocouple and a pyrometer, As it is well known that using a single linear or quadratic relationship to estimate the heat flux from the measured surface temperature does not provide the accuracy required to close the cell heat balance, this approach was not used in this study, Instead, the fundamental natural convection and radiation heat flux equations were used systematically for each measurement point, Practically, this means that the ambient air temperature and at least one ambient radiative temperature must also be known in addition to the surface temperature for each measurement point. Sometimes, the radiative heat flux could not be accurately estimated using a single ambient radiative temperature, In those cases, a more accurate estimation based on two ambient radiative temperatures and corresponding view factors has been used instead, It turns out that although at least three temperature measurements are required to estimate a single heat flux, it takes a lot less time to make those temperature measurements using a pyrometer than directly measuring the heat flux using an expensive heat flux meter, Furthermore, no loss in accuracy was detected when using this approach as the cell heat balance could be closed within 5%, the level of accuracy typical of cell heat balance assessment using heat flux meter.

Jan 1, 2004

By R. W. Boyle

"PREFACEThis paper comprises two parts. The first part discusses lithochemical surveys based on major, minor and trace elements in whole-rock samples from primary enveloping halos. The second part continues with discussions of surveys based on leakage halos, zonation of elements, stable and radioactive isotopic distributions, geothermometric, geobarometric, thermolumin escent, pedochemical, hydrochemical, atmochemical and biogeochemical methods. A selected bibliography follows the second part of the paper.ABSTRACTAreal (two-dimensional) geochemical surveys, based mainly on secondary dispersion halos and trains in media such as surface waters, soils and drainage sediments, have proven particularly successful in recent years and have greatly assisted in the discovery of a large number of varied mineral deposits. Three-dimensional surveys based on primary halos and leakage halos have received relatively little attention by research organizations and the mineral industry. Such surveys offer many novel approaches for discovering blind mineral deposits deeply buried below overburden or within their host bedrocks. This paper reviews detailed methods for the discovery of blind mineral deposits based on sampling rocks (lithochemical methods), soils and other types of overburden (pedochemical methods), waters (hydrochemical methods), gases (atmochemical methods) and biological materials (biogeochemical methods) . All are applicable to the discovery of blind deposits; the efficacy of each or in combination depends essentially on the type of mineralization, the extent of the development of the primary and secondary dispersion halos, and the finances available for sampling techniques employing overburden drilling, bedrock drilling, and sophisticated water, gas and vegetation collection."

Jan 1, 1982

Slurry flow, including flow through the charge, through the discharge grates, along the pulp lifters and its discharge from the mill is an important contributor to the efficiency of the grinding process within a SAG mill. Poor transport of finer ground material can adversely affect grinding leading to excess energy consumption and over-grinding of fine material. This paper extends a 1-way coupled DEM-SPH method to three dimensions and applies it to a 1.8 m diameter by 0.6 m long AG/SAG pilot mill. This provides detailed information on the internal flow of slurry within a SAG mill, including the prediction of dry regions and of slurry pooling. Full 3D analysis also allows the pulp flow patterns into and out of the mill via pulp lifter chamber to be investigated.

Jan 1, 2012

By E. P. Williams

"Prince Edward Island, Canada's smallest Maritime Province, is located in the southwestern part of the Gulf of St. Lawrence. The Province is more or less centrally located in the Maritimes Basin, a large intermontane basin within the Appalachian orogenic belt. The Maritimes Basin is subdivided into sub-basins and uplifts which exhibit two dominant structural trends: east and northeast. The Basin is known to be petroliferous because of the seeps, shows, oil shales and albertite found in southern New Brunswick and northern Nova Scotia and the gas and oil produced from the Stony Creek field near Moncton, New Brunswick.Permian beds are exposed on the Island, mostly along sea-cliffs. A maximum thickness of about 5,000 feet of red beds -shales, sandstones and conglomerates -make up the sequence. Over most of the Island, the Permian section is much thinner. Four key wells (Mississippian tests) and several shallower tests have been drilled. The Pennsylvanian-Mississippian section thickens rapidly off the Port Hill Uplift at the northwest, where it is less than 4,600 feet thick, and continues to thicken to about 20,000 feet in the Cumberland Basin at the southeast. Geological and geophysical data combine to give us the structural picture of the deeper beds.Prospective reservoir rocks are primarily in the Missis-sippian Horton and Windsor groups. Prospects are:-1. on or over structural highs in the basement; 2. on anticlines or fault highs; 3. over or peripheral to salt domes or salt-core anticlines; 4. at truncation pinchouts of Mississippian prospective beds; 5. in basal sandstone or granite wash on the pre-Carboni-ferous basement; and 6. in facies traps at changes from sandstone to shale or porous to tight carbonate rocks."

Jan 1, 1967

By J. W. Craig

THERE are, broadly speaking, three classes of refractories: acid, basic, and neutral. Fireclay, diaspore, silica, and the sillimanite group of minerals are included in the acid class, which for the most part are not very resistant to basic slags. The neutra! class includes chrome, graphite, and silicon carbide, while most important in the basic class are magnesite and dolomite. Although chrome is a neutral refractory, it has no sharp distinction from magnesitic refractoriness. The two are mineralogically (1) and chemically related, and there is available on the market a complete range of brick from straight chrome to straight magnesite. In many indus trial applications, one. type may be replaced by another. The present paper is confined entirely to such refractories. The following types of basic and neutra! brick, each sold under sorne special trade name, are available for use in Canada: (1) Burned chrome from crude ores (2) Burned chrome from treated ores (3) Chemically bonded (unburned) chrome-magnesite ( 4) Burned chrome-magnesite (5) Chemically bonded ( unburned) magnesite-chrome (6) Chemically bonded (unburned) high-iron magnesite (7) Burned high-iron magnesite (Regular) (8) Burned low-iron magnesite (9) Burned olivine-magnesite (10) Burned magnesitic dolomite-chrome (Magnecon) (11) Chemically bonded magnesitic dolomite-chrome (Magmecom) (12) Dolomitic brick

Jan 1, 1936

By Jie Li, Xinyu Liu, Yan Chen, Linjian Ma, Yasong Wang

Nonlinear time-dependent response analysis of salt cavern under extreme loads in disaster mode is of great importance to the safety and disaster prevention of gas storage group. Uncontrolled blowout is one of the extreme conditions for compressed-air cavern operation. Based on the geological structure of Jintan salt deposit, China, the numerical model of the complete process of water solution, cyclic operation, and internal pressure runaway was developed. The effects of rapid unloading on the stress filed, the progressive failure of surrounding rock, the volume convergence of storage cavern, and the ground subsidence were simulated employing an elasto-viscoplastic damage constitutive equation for rock salt. The results indicate that the damage and failure zones propagate much larger in the mudstone interlayer than in the host salt. The volume of damage and failure zones surrounding salt cavern induced by unloading process is 5~6 times that of cyclic injection and withdrawal process. The average volume convergence rate of salt cavern reaches 0.012%/d~0.013%/d, which is 6~6.5 times that induced by cyclic operation. The ground subsidence exhibits a typical funnel curve. The affected region of ground subsidence due to rapid unloading in the blowout period is about two times the maximum cavern diameters. Furthermore, double cavern analysis reveals that the interaction between adjacent caverns may be ignored so long as the pillar width is larger than two times the maximum cavern diameters.

Jan 1, 2015

By Sib N. Mukherjee

Main ventilation fans are used in all the mines and they run continuously 24 hours a day and 365 days in a year. Any improvement in their performance can lead to considerable power saving. The basic principle for selection, operations, and related measures are discussed in brief in the paper. The contributions of different elements of mine fan on its performance are discussed in brief. The means to improve efficiency of a running fan is also discussed and the importance of saving even 1 Kwh is elaborated. It is found that the cost of the energy saved may even permit a replacement fan to be procured in a few years time.

May 1, 2007

By Nn Li

Energy consumption in commercial buildings has been increasing rapidly in the past decade. The knowledge of future energy consumption can bring significant value to commercial building energy management. For example, prediction of energy consumption decomposition helps analyze the energy consumption patterns and efficiencies as well as waste, and identify the prime targets for energy conservation. Moreover, prediction of temporal energy consumption enables building managers to plan out the energy usage over time, shift energy usage to off-peak periods, and make more effective energy purchase plans. This paper proposes a novel model for predicting heating, ventilation and air conditioning (HVAC) energy consumption in commercial buildings. The model simulates energy behaviors of HVAC systems in commercial buildings, and interacts with a multiagent systems (MAS) based framework for energy consumption prediction. Prediction is done on a daily, weekly and monthly basis. Ground truth energy consumption data is collected from a test bed office building over 267 consecutive days, and is compared to predicted energy consumption for the same period. Results show that the prediction can match 92.6 to 98.2% of total HVAC energy consumption with coefficient of variation of the root mean square error (CV-RMSE) values of 7.8 to 22.2%. Ventilation energy consumption can be predicted at high accuracies (over 99%) and low variations (CV-RMSE values of 3.1 to 16.3%), while cooling energy consumption accounts for majority of inaccuracies and variations in total energy consumption prediction.

Aug 1, 2013

By I. M. Gordon, J. Blackshaw

"Run-of-mine ore is reduced to 4 per cent on 4 mesh (3/ 16 inch), using four stages of dry crushing. The mill feed is then reduced to 2 per cent on 48 mesh and 60 per cent through 200 mesh, using one stage of ball milling in cyanide solution. During the subsequent treatment about one-tenth of the tonnage is removed as a table concentrate and ground to 77 per cent through 325 mesh. The size of the mill tailing is 66 per cent through 200 mesh.Four stages of ore reduction began when the dry crushing plant at No. 26 Shaft came into operation at a maximum rate of 440 tons an hour on July 31, 1941. A detailed description of the crushing plant was published in C .I .M. Trans., Vol. LVI, 1953.One-stage ball milling in cyanide solution came into full operation on January 11, 1938. The ball milling plant had a capacity of 4800 tons daily when reducing mill feed at 2. 7 per cent on 1/ 4 inch to 54. 3 per cent through 200 mesh. Primary grinding to 60 per cent through 200 mesh commenced May 22, 1945, when the feed was 3 per cent on 4 mesh. Under these conditions the capacity of the ball milling plant is estimated at 4300 tons daily. A description of the 11 Hollinger Crushing and Grinding Plant"" by D. C. McLaren was published in the Canadian Mining Journal, June 1944.The concentrate grinding circuit using a 7 x 15 low discharge ball mill and a 19-foot diameter bowl classifier with a 6-inch centrifugal pump to close the circuit began operating in the ball milling plant on October 24, 1939."

Jan 1, 1965

By Fathi Habashi

"Hydrochloric acid (HCl), although more expensive than sulfuric, find uses as a leaching agent in reactions involving iron oxide. The reason for this substitution was the discovery that oxyhydrolysis of ferrous chloride by which HCl can be recycled economically. This avoided the pollution of the environment by ferrous sulfate. It was found further that the rate of leaching of sulfides is faster when HCl is used as compared with sulfuric apparently due to the formation of aqueous chlorine. In case of refractory gold ores, HCl leaching under pressure avoids the use of cyanide solution since gold chloride is produced which can be recovered by standard methods. Hydrochloric acid find also uses in the leaching of scheelite and apatite but its use in leaching clay and anorthosite is questionable.INTRODUCTION Sulfuric acid is the cheapest acid and is used as a leaching agent in many hydrometallurgical processes. However, hydrochloric acid (HCl), although more expensive since it is prepared by reaction of sulfuric with sodium chloride, has replaced sulfuric acid in many reactions involving iron oxide. It replaced sulfuric acid for the first time in 1960s in pickling of steel because of pollution problems (Habashi, 2000). Ferrous chloride produced in pickling can be economically decomposed to ferric oxide and HCl according to:2FeCl2 + 2H2O + 1/2O2 ? Fe2O3 + 4HCl (1)which also shows that the acid can be regenerated but ferrous sulfate cannot be economically decomposed to recover sulfuric acid for recycle. Since then, HCl has been used in many leaching processes. Hydrochloric acid is a corrosive acid and is usually handled in rubber-lined equipment. REGENERATION OF HYDROCHLORIC ACID Regeneration of HCl is conducted in fluidized bed or in spray roaster Fluidized bed oxyhydrolysis In a fluidized bed, ferrous chloride solution is introduced onto a bed of hot ferric oxide where heating is provided by the hot fluidizing combustion gases (Figure 1). The solution is fed on top of the bed of oxides. The liquid feed wets the outer layer of the hot oxide particles and is quickly evaporated to form a layer of new solid oxide on top of the existing oxide, thereby producing dense homogeneous particles."

Jan 1, 2017

By K. P. Wright

THREE OF the gold mines in the Red Lake Camp operates fluid bed roasters in their milling circuits. The mines are Campbell Red Lake, Cochenour Willans, and Dickenson. The roasters are used for the autogenous roasting of a flotation concentrate for subsequent gold recovery by cyanidation. Cochenour and Dickenson operate single stage reactors, whilst Campbell use a two-stage system. Ore treated by the mines is similar in that the major part of the gold is associated with arsenopyrite. Other sulphides present are pyrite, pyrrhotite, stibnite and sphalerite. Gangue minerals are mainly quartz, with carbonates and talc. Mineralization is, for the most part, extremely fine, and there is intimate association between sulphides and quartz, so much so, th at a picked specimen of apparently massive arsenopyrite will frequently contain as much as 80 per cent gangue. Gold recovery by straight cyanidation on this type of ore would not be higher than 80 per cent and

Jan 1, 1961

By L. Szecowka, M. Poskart, Siwka M. . J.

Oxides of nitrogen, created during combustion, are the most hazardous components of atmospheric pollution. However, it is possible to limit the negative influence of hazardous components on the natural environment. An experimental appartatus was built to determine the influence of the following "primary methods" on the reduction in concentration of NOx: air staging, reburning and flue gas recirculation. The influence of the simultaneous usage of the primary methods on reduction in NOx emissions was also examined. A significant increase in the efficiency of NOx reduction was achieved in two cases.

Jan 1, 2004

By C. J. R. Braithwaite, Giancarlo Rizzi

"Abstract-The Navan zinc-lead ore deposit (70 million tonnes) is hosted principally (97%) by the Meath Formation (Lower Carboniferous, Courceyan, Navan Group), comprising a lower, mainly carbonate mudstone unit, the Stackallan Member, and an upper grainstone-dominated unit. The Stackallan Member, about 60 m thick, comprises about 35 peritidal cycles including an oolitic grainstone interval. Grainstones forming the upper part of the formation, about 150 m thick, comprise at least six shallowing-upward ramp cycles. Emergence horizons are indicated by subaerial dissolution surfaces, in situ breccias, and a single palaeosol.Most dolomitization at Navan is confined to the Meath Formation. The linear dolomite body, trending NE-SW, has a flattened, laterally limited, tabular geometry in cross-section, suggesting that dolomitizing fluids initially rose vertically, cross-cutting stratigraphic and sedimentological boundaries, although fluid flow was subsequently controlled by these features. Three stages of dolomitization are indicated by textural relationships, cathodoluminescence (CL), oxygen isotopes, and fluid inclusion data. Stage 1 crystals, with generally dully luminescing cores and up to six overlying subsidiary zones, are the main replacive phase. Crystal surfaces are commonly corroded and overlain by bright stage 2 rhombs (which also form new nuclei lining molds and fractures). Three subsets of zones are present in stage 2 crystals: bright, non-luminescent, and dull; these are locally separated by additional corrosion surfaces. Stage 3 comprises relatively large baroque crystals, generally dully luminescent but with up to seven sub-zones. Isotopic and fluid inclusion data suggest growth of successive stages from waters which became progressively hotter (60°-160°C).The distribution of the ores follows the dolomite trend. Ores were precipitated between Stages 1 and 2 of dolomite growth, following Stage 2, and also during the nucleation and growth of Stage 3 crystals. Dolomitization and mineralization appear to have been temporally and genetically related. The cyclic sedimentation of the host rocks, which accentuates lithological and petrographical contrasts between depositional units, controlled dolomitization. The relationship between dolomitization and mineralization, which is closely associated with faults, provides powerful exploration criteria. The recognition of these features in limestones elsewhere in the Irish ore field may point toward unrecognized zinc-lead prospects."

Jan 1, 1997

By C. J. Newman, D. J. Kemp, R. M. Sweetin

"The smelter is described by area; feed preparation, continuous furnace line, gas handling and auxiliary systems, blister refining, Hazelett casting of thin anodes, and scrap remelting. Early smelter campaign data is presented and compared to design. Some modifications to the basic design of the furnaces and gas trains are indicated, with their respective impacts on improving smelter performance.Plant compactness, the use of jumbo tanks, and a highly automated electrode handling system are featured in the refinery description, with brief coverage of the liberator and slimes leaching sections. Early experience in refining thin regular Hazelett anodes, and submersible pump recovery of raw slimes are relayed, together with automatic stripping from titanium blanks.Refinery tonnages and operating parameters are given showing the relatively trouble-free attainment of refinery design performance.IntroductionPrevious papers and articles ( 1), (2) ,(3 ) have described the metallurgical facilities serving the copper-zinc-silver Kidd Creek orebody located near Timmins, Ontario. For convenience a brief review of their mid-1983 operating status is presented.The concentrator, originally designed for 9,000 short tons, was commissioned in late 1966. It can now comfortably process over 13,000 metric tonnes per day largely as a result of the addition of a fourth circuit in 1978."

Jan 1, 1984

By C. Kunze

ABSTRACT Although closure sureties cover works that are carried out during the existence of a mining company, certain liabilities are not known when the surety is established and become apparent only in a late stage of the closure phase, or even after the site has been relinquished. This paper supports the concept that these financial risks lend themselves to insurance solutions. Making insurance for unknown liabilities mandatory while defining unambiguous legal conditions could create a viable market for insurance products, provide a sufficient statistical basis for the calculation of premiums, and reduce costs.

Jan 1, 2013