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By H. O. Lien

Among the known iron deposits in Canada, many are of low grade and require beneficiation to produce an acceptable blast-furnace feed. Some of the deposits have never been considered for commercial exploitation due to the lack of a suitable concentrating process. A number of deposits of this type are located in Northern Ontario. The problem in upgrading these deposits is three fold. Firstly, the iron occurs as a mixture of magnetite and hematite. Secondly, the grain size of the material can be fine to very fine. Thirdly, the complex mixture of gangue minerals, which consists invariably of silica, flaky silicates and carbonates, slimes excessively on fine grinding. Algoma's efforts to concentrate these iron-bearing materials culminated in the development of a "Selective Flocculation and Desliming Process" employing slimes removal as the sole beneficiation technique. The process was applied successfully in the laboratory using two stages of grinding and a total of seven deslimings. Prior to the removal of slimes, the iron-bearing fines were selectively flocculated from a thoroughly dispersed pulp using a modified starch as flocculant, Sodium silicate was employed as dispersant. An attempt was made to optimize some of the process variables using material from one specific iron formation near the town of Geraldton in Northern Ontario. The preparation of the starch proved most critical. This matter, and the method used to evaluate the degree of breakdown of the starch molecule, are therefore discussed in some detail.

Jan 1, 1978

By R. J. Evans

The generation and disposal of solid waste from electric utility plants using a lime or limestone wet-scrubbing system and the potential effects on the environment were estimated for 1975 and 1980. The study indicated that in 1975 approximately 5.8 million tons of desulfurization solid waste (50 percent solids) will be generated. In 1980, when it is estimated that desulfurization will become commercially accepted, approximately 71.4 million tons of this material will be generated for disposal and/or utilization. The desulfurization waste material when combined with lime, fly ash, and water may have potential for use as a roadbase material, landfill reclamation, and synthetic aggregate.

Jan 1, 1974

By H. C. Boydell

Introduction Situated in the district of South Lorrain, some 16 miles southeast of Cobalt, Ontario, and reached from that centre either by branch line of the T. & N. O. railway or by what, for a mining camp, is a reasonably good road, the Keeley mine, owned by the Keeley Silver Mines,' Ltd., has had its history recorded by C. W. Knight (1). Silver was first discovered in South Lorrain, in Woods' vein, on Keeley property, in 1907, and the Keeley mine has been described by Knight (2) and Bell (3). The total production to February 28th, 1930, has been 10,760,107 ounces of silver and 1,285. 434 pounds (weight) of cobalt.

Jan 1, 1931

Explosive manufacture, handling and transportation is hazardous and special precautions should be taken while manufacture, handling and transportation. Various regulations and rules defined in explosive act and factories act of India are discussed in this communication. General process control measures during the manufacturing of different types of explosives are also dealt in detail. Various processes hazardous in manufacture of various explosives like slurry explosives, PETN, detonators, styphnic acid, lead azide and lead styphnate and special precautions to be taken during the manufacture of the above explosives are also discussed.

Jan 1, 2007

By C. H. Fisher

Sulphuric acid of various concentrations has long been used as a reagent in the determination of olefins and aromatics in hydrocarbon oils4 such as gasoline, kerosene, and neutral oils from coal-tar distillates. Despite its long use, however, there is no general agreement as to optimum conditions and concentration of acid, and numerous methods and modifications have been recommended. In most cases, treatment of the neutral oil with 80 to 90 percent sulphuric acid, followed by distillation to the original endpoint to remove olefin polymers, is recommended for the estimation of unsaturated hydrocarbons. The distillate thus obtained is taken as olefin-free oil and used in later stages of the anlysis. Aromatic hydrocarbons generally are determined in the olefin-free oil by suphonation with more concentrated acid (96 to 100 percent and fuming sulphuric acid are recommended), the hydrocarbons not attacked and removed as water-soluble sulphonic acids being considered as saturated hydrocarbons. In some cases the saturates are examined further by differentiating between cyclic (naphthenes) and acyclic hydrocarbons (paraffins), Generally this is achieved by physical methods, although strong sulphuric acid is known to react preferentially with some types of saturated hydrocarbons. It was the purpose of the present work to make a general study of this type of analysis and to investigate the reactions of hydrocarbons under conditions often used in analyses that employ sulphuric acid reagents. Since previous work is not in good agreement, the optimum concentrations of acid for the different stages of the analysis were determined. Several sulphuric acid methods previously recommended and new modifications were compared, two synthetic solutions being used as the reference oil. The results obtained are presented below under separate headings.

Jan 1, 1937

By C. H. Fisher, Abner Eisner

"INTRODUCTION Sulphuric acid of various concentrations has long been used as a reagent in the determination of olefins and aromatics in hydrocarbon oils 4 such as gasoline, kerosene, and neutral oils from coal—tar distillates. Despite its long use, however, there is no general agreement as to optimum conditions and concentration of acid, and numerous methods and modifications have been recommended. In most cases, treatment of the neutral oil with 60 to 90 percent sulphuric acid, followed by distillation to the original endpoint to remove olefin polymers, is recommended for the estimation of unsaturated hydrocarbons. The distillate thus obtained is taken as olefin—free oil and used in later stages of the anlysis. Aromatic hydrocarbons generally are determined in the olefin—free oil by suphonation with more concentrated acid (96 to 100 percent and fuming sulphuric acid are recommended), the hydrocarbons not attacked and removed as water—soluble sulphonic acids being considered as saturated hydrocarbons. In some cases the saturates are examined further by differentiatingbetween cyclic (naphthenes) and acyclic hydrocarbons (paraffins). Generally this is achieved by physical methods, although strong sulphuric acid is known to react preferentially with some types of saturated hydrocarbons,It was the purpose of the present work to make a general study of this type of analysis and to investigate the reactions of hydrocarbons under conditions often used in analyses that employ sulphuric acid reagents. Since previous work is not in good agreement, the optimum concentrations of acid for the different stages of the analysis were determined. Several sulphuric acid methods previously recommended and new modifications were compared, two synthetic solutions being used as the reference oil. The results obtained are presented below under separate headings."

Dec 1, 1937

By Robert C. Ellman

The Bureau of Mines investigated the factors that cause agglomeration of lignite by freezing during winter shipment and sought methods to avoid it. Tests showed that lignite may be freezeproofed by removal of the relatively small quantity of moisture involved in forming the frost crystals which cement particles together, or by controlling the crystal characteristics. Adding dried lignite fines proved to be an effective and superior freezeproofing method. Commercial adoption of this method has been successful.

Jan 1, 1965

By J. P. Powell

This report provides information on the techniques and results obtained on representative waterflooding projects in Cowley County, Kans. Records show that waterflooding was begun as early as 1935, but not until 1948 was the method expanded. The greater depths to the oil-producing formations in this area compared to those in eastern Kansas undoubtedly delayed the widespread use of secondary-recovery methods. This report presents a discussion of four waterflooding projects in Cowley County, Kans. The locations of these projects are shown in figure 1. The projects have been in operation from 1 to 7 years and have produced more than 1 million barrels of additional oil by injecting 11.5 million barrels of water. The projects are designed to take advantage of elevation and height of the separator tank to collect by gravity flow the produced brine at the respective treating or storage tanks. The closed-type water system is used on three of the projects and an open-type water conditioning system on the fourth. On one of the projects, which was drilled along a narrow shoestring formation, alternate well, were converted to input wells. However, most of the input wells for flooding converted producing wells.

Jan 1, 1958

By D. A. Paice

A power supply to operate fluorescent or mercury vapor lamps from 300 volt dc coal mine trolley wires has been developed for the Bureau of Mines. A high frequency regulated inverter unit incorporates ballasts for a mix of lamp loads up to 650 watts. For 600 volt trolley systems an additional power converter unit was developed to step down the dc voltage to 300 volts for the inverter unit. Both units have operated in a working coal mine for over 12 months without need for servicing. The lamp load in these tests included two 100 watt mercury vapor head lamps and six 75 watt fluorescent lamps.

Jan 1, 1979

By Irving Hartmann, John Nagy, Donald Mitchell

"SUMMARY AND CONCLUSIONThe test data indicate that water infusion of the Pittsburgh coal seam does not reduce the amount of fine dust produced during mining operations to the extent reported elsewhere. Wide variations in the amounts of dust collected in the air current were noted in duplicate samples and repetitive tests. Changes in depth and location of the infusion holes and amount of water injected and addition of a wetting agent to the water had little effect on the amount of dust liberated.Water was forced readily into the coal. Some water flowed out along the cleats, but an appreciable amount remained in the seam. Little or no water pene¬trated the coal seam above the upper infusion holes.The average dust concentration (with and without infusion) in the return air, 40 feet outby the working face, was 25 million particles per cubic foot during undercutting, 20 million during drilling, 75 million during shot firing, and 20 million during hand loading. At the working face the average concentration was 3 to 6 times higher. The concentrations were measured at an airflow of 1,600 cubic feet per minute (c.f.m.) at the face.On the basis of this short investigation, no final conclusions can be made on the effectiveness of water infusion in reducing the amount of fine dust liberated during mining in the Pittsburgh coal seam. However, the data indicate that dust reduction resulting from infusion would be small.INTRODUCTIONThe production of fine coal dust is an inherent part of nearly every phase of mining. The use of large, high-speed continuous-mining machines and other mechanical equipment has increased dust production. In addition, in coal seams that have been subjected to high pressures for a long period, and particularly in dry and friable seams, some very fine dust is in the seam before mining. Much effort has been devoted to allaying and collecting at its source the fine coal dust released during mining. One of the comparatively recent techniques that has been developed for this purpose is infusion of water or other liquids into the coal seam. This method consists of injecting water under pressure into a coal seam to neutralize the fine dust released during mining. The water generally is introduced through bore holes in the face before undercutting."

Jul 1, 1957

By G. W. Birge

Carbonizing properties of the principal coalbeds of Elk, Clarion, Jefferson, Clearfield, and Centre Counties, Pa,, are described in this Bureau of Mines report, Twenty-six samples, representing the Upper Freeport, Lower Freeport, Upper Kittanning, Middle Kittanning, Lower Kittanning, and Brookville beds, were carbonized by the Bureau of Mines--American Gas Association (BM-AM) method, and yields of products and physical properties of cokes were determined. Expansion or contraction of the majority of the samples was measured in the Bureau of Mines sole-heated oven. Chemical analyses, agglutinating values, and free-swelling indexes are given for all samples. In this area the coals generally are characterized by high sulfur and moderately high ash content, and their suitability for metallurgical use would depend largely upon satisfactory cleaning. The samples from Elk, Clarion, and Jefferson Counties were high-volatile A bituminous In rank, whereas, most samples from Clearfield County and all those from Centre County were of medium-volatile rank. Coals from Clarion County had dry, mineral- matter-free fixed-carbon contents ranging from 56.5 to 60.3 percent and were weakly coking. With the exception of two samples which contained excessive ash, the medium-volatile coals of Clearfield and Centre Counties were strongly coking and, as indicated by sole-oven expansion results, would require blending with lower rank coal to avoid oven damage.

Jan 1, 1963

By C. M. Frost

The hydrodesulfurization characteristics of a residual fuel prepared from Wilmington, Calif., crude oil were determined at temperatures from 600° to 900° F, pressures of 200 to 800 pSig, and space velocities from 0.2 to 2.0 Vo/Vc/hr, using cobalt molybdate type catalysts. A prediction equation, developed from the experimental data, satisfactorily predicts the fraction of total sulfur that can be removed under any combination of operating conditions within the ranges investigated. Yields and properties of the low sulfur product are correlated with the fraction of total sulfur removed. Kinetic calculations show that the apparent reaction order and activation energy change with space velocity and temperature.

Jan 1, 1970

By W. W. Agey

An inexpensive technique that laboratory studies indicated would significantly reduce seepage in irrigation canals was devised and tested through research sponsored by the Bureau of Reclamation and the Missouri River Basin Field Committee. Laboratory tests simulating optimum field conditions determined that easily applied sodium carbonate solutions made test beds of canal lining materials virtually impermeable for long periods. The study comprised alternative laboratory treatments of 3-inch-deep test beds of canal earths with 74 water-soluble chemicals in search of one 01' more that would effectively improve the water barrier characteristics of the component clays. Sodium carbonate, one of the least expensive, was among the most effective. The addition of 0,4 lb of reagent per sq yd greatly reduced the seepage from typical, highly permeable test beds. The reagent penetrated and sealed surface for about a 1.5-inch depth.

Jan 1, 1965

By I. Dymov, W. Phillips

A process has been evaluated, on a continuous pilot plant scale, to treat refractory gold arsenopyrite/pyrite concentrates. The process consisted of biological leaching to partially oxidise sulphides, followed by pressure leaching for complete sulphide oxidation and arsenic precipitation, followed by liquor neutralisation and cyanidation of the autoclave residue for gold recovery. This paper provides a brief description of the treatment flowsheet and discusses some of the main parameters and results of the process. During integrated pilot plant campaigns, it was confirmed that acceptable sulphide oxidation and gold extraction of 96-98% could be achieved by a two-stage oxidation with BIOX® (4 days total retention time) followed by PDX (40 minutes retention time at 220°C). Only partial arsenic precipitation was achieved in the autoclave, followed by complete precipitation by neutralization under atmospheric conditions. The overall process could be significantly simplified, and capital and operating costs reduced, with a flowsheet modification allowing all of the BIOX® liquor to bypass the autoclave directly to the neutralization circuit.

Jan 1, 2004

Stellite-6 coatings were formulated on two Ni-base superalloys, namely Superni 75 and Superni 600, by a shrouded plasma-spray process, and the oxidation behaviour of these coatings has been investigated in air and in an aggressive environment of Na2SO4- 60%V2O5. Accelerated oxidation tests were conducted in a silicon-carbide tube furnace under cyclic conditions at an elevated temperature of 900°C for 50 cycles. Each cycle consisted of 1 h heating and 20 min cooling in air. A thermogravimetric technique was used to approximate the oxidation kinetics. The corrosion scales were characterised by XRD, SEM/EDAX and EPMA analysis. It has been observed that the coatings nearly followed the parabolic rate law of oxidation. Overall weight gain conceived in air was just 51% of that in the aggressive environment in the case of coated Superni 75, whereas in case of coated Superni 600, the cumulative weight gain in air was found to be one-third of that in the Na2SO4-60% V2O5 atmosphere. Furthermore, the coating showed very good adherence to both of the substrates during the course of air oxidation, whereas some superficial cracks were observed near the edges of the specimens during the molten salt induced oxidation. XRD analysis revealed the presence of phase-like CoO, CoCr2O4 and Cr2O3 in the oxide scales, which are reported be protective against high-temperature oxidation. The XRD results were further supported by SEM/EDAX and EPMA.

Jan 1, 2005

By A. R. Sorta, D. C. Sego

ABSTRACT The settling, shear strength, and index properties of oil sands fines-sand mixture tailings (FSMT) for a wide range of solids and fines content are investigated. Results indicate that the liquid limit of FSMT obeys a linear mixture law. The fines-water ratio (FWR) governs the permeability of composite tailings (CT) and CT with comparable geotechnical behaviour can be produced from the same initial FWR mixtures. A phosphogypsum (PG) dosage > 900 mg/kg does not improve the dewatering behaviour of CT. The undrained shear strength of FSMT at the liquid limit is approximately 2.4 kPa, but is dependent on fines content at the plastic limit.

Jan 1, 2013

By Wayne D. Gould

The Cities Service Company's Pinto Valley mine and concentrator lie about 6 miles west of the town of Miami, Arizona at an elevation of approximately 4,000 feet above sea level. The concentrator started its first ballmill in July 74 and all six were available by November. Every effort was made to reduce capital costs, consequently, each unit process was studied critically to eliminate excess capital costs without loss of efficiency. Equipment selection was made on the basis of proven dependability and operating costs rather than on low bids. The result is a very workable plant with some important innovations. The concentrator is nominally 40,000 tons per day. The flowsheet is typical with 3 stage crushing, single stage closed circuit grinding, flotation, regrinding of rougher concentrate and cleaning of the rougher concentrate. The major equipment list is: 1 60 x 89 Traylor Primary Crusher 1 84" x 20' Stevens-Adamson Apron Feeder 3 7' x 16' Double Deck Tyler Screen 3 7' Nordberg Standard Crushers 6 8' x 20' Tyler Screens

Jan 1, 1975

By J. G. Kirby

According to the Bureau of Mines annual survey, there were 319 petroleum refineries in the United States as of January 1, 1957 capable of processing 9,123,674 [ ]-barrels of crude oil daily. This was the first time in eleven years that the total number of refineries increased. The crude throughput capacity of the refineries increased 491,284 barrels daily (6 percent) above the January 1, 1956 capacity. The East Coast and Texas Gulf Coast refining districts accounted for 60 percent of the additional capacity installed. Three new refineries were put into operation on the East Coast during the year with a total daily crude throughput capacity of 154,434 barrels while the other refineries in the district report a net loss in capacity, installing equipment capable of processing 140,000 barrels, but dismantling equipment with a capacity of 150,100 barrels. In the Texas Gulf Coast district, one new refinery with a daily crude oil capacity of 5,000 barrels was placed in operation in 1956 and 143,700 barrels of crude capacity was added to existing refineries. The capacity of the average refinery to process crude oil increased from 27,145 barrels daily to 28,601 barrels in 1956.

Jan 1, 1957

By L. Tong, D. Robinson

"The stirred milling of nickel laterites offers possibilities for improving liberation and selective size reduction of soft nickel-bearing minerals in laterites. Batch grinding tests were performed in a netzsch™ lME4 stirred mill on siliceous goethitic, goethitic, and saprolitic nickel laterites. Tests on the -2,000 µm sample displayed the effects of selective comminution. The -38 µm product of grinding the -2,000/+38 µm feed confirmed the effects of selective grinding and nickel upgrading. Size classification followed by stirred milling is recommended for nickel upgrading. The energy requirement in the stirred milling was also investigated.RÉSUMÉ le broyage par billes de latérites comportant du nickel offre des possibilités d’amélioration de la libération et de la réduction sélective de la taille des minéraux nickélifères tendres dans les latérites. Des essais de broyage en vrac ont été effectués dans un broyeur à billes netzschMD lME4 sur des latérites nickélifères à goethite siliceuse, à goethite et saprolitiques. Des essais sur l’échantillon -2000 µm présentaient des effets d’une comminution sélective. le produit -38 µm de l’alimentation -2000/+38 µm confirme les effets d’un broyage sélectif et du rehaussement de la teneur en nickel. Pour améliorer la teneur en nickel, il est recommandé de classifier le minerai en fonction de sa granulométrie, puis d’effectuer un broyage à billes. l’énergie requise pour le broyage à billes a aussi été étudié."

Jan 1, 2015

By D. S. Burgess

An investigation of the hazard of spillage of liquefied natural gas (LNG) onto water is described. About 2,000 gallons of LNG were consumed in various tests. The initial vaporization rate of LNG following spillage was found to be 0.037 lb/ft2 sec; when the spill was confined, this vaporization rate was moderated after about 20 seconds by the growth of an ice layer on the water surface; when the spill was unconfined, a coherent ice floe was not observed and the vaporization rate was essentially time independent. The maximum diameter (in feet) of the spreading LNG pool was found to be given by 6.25 Wo 1/3, where Wo is the weight of LNG in pounds, Downwind of a natural gas source, time-averaged methane concentrations were given in good approximation by standard air pollution equations. However, peak concentrations were as much as twentyfold higher than average, adding an additional factor to the assessment of hazard. The effect of layering by the cold vaporized natural gas was similar to the effect of a temperature inversion on normal gases in the atmosphere. Small-scale explosions were observed on pouring LNG onto a water surface; no single explanation seems pertinent to all of the incidents observed.

Jan 1, 1970