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By S. Abe

An extensive study has been carried out to determine the true cause of floating slimes precipitation which sometimes occurs and badly affects the quality of copper cathodes. Soluhilities of floating slime compounds systematically measured for the ternary system As-Sb-Ri added solely or in combination with conventional copper electrolyte (63°C) and bench scale electrorefining experiments done by varying electrolyte composition, have shown conclusively that the level of Sb(V) ions plays a substantial role in the precipitation mechanism. It was, therefore, speculated that controlling the level of the less soluble S b ( V ) ions below a certain critical level should result in a complete elimination of the undesirable precipitation. This can be easily achieved, for instance, by the addition of a reducing agent such as SO2 gas and the simultaneous employment of a certain type of cheating agent that effectively removes excessive Sb and Bi from the contaminated electrolyte. Long-term pilot testing conducted in line with the above speculation has confirmed the SO2/chelating resin scheme to be industrially very attractive and feasible.

Jan 1, 1987

By J. R. Hurley

The continuous flow, horizontal drum blender has dynamic properties which may be described by the same type of equations which often arise in electrical filter analysis. Furthermore, the equations may be readily solved by the same techniques used in electrical control analysis. For this reason the blender model developed is termed an "Electric Analog", although strictly speaking it is a mathematical model. Presentation of the dynamic performance of the blender as an electrical (or mathematical) model is desirable for several reasons. The model can be of assistance in correlating performance data with equipment design parameters. The model 'can be used with other process equipment models for simulation of an entire plant operation or in stability studies. In addition, the model may be useful in providing insight into the actual blending mechanism, or it may suggest a similar method of analysis for other closely allied equipment.

Jan 1, 1967

By C. A. Fleming, K. W. Sarbutt, P. K. MacPhail

The SART process has been developed for Teck to treat bar­ren solution from the cyanidation/CIP process that has been developed for the Lobo-Marte project in Chile. The objective of the process is to recover cyanide in a form that is suitable for recycling to the leaching part of the process. The Marte and Lobo ore bodies require a dosage rate of about 2 kg/t NaCN, of which only 0.5 kg/t is truly consumed (as thiocyanate, cyanate and ferrocyanide species). The remaining -1.5 kg/t is present as cop­per cyanide (-1 kg/t) and free cyanide (-0.5 kg/t), and is poten­tially recoverable and recyclable. SART is an acronym that describes the unit operations in this cyanide recovery process; namely, .. Sulphidization .. Acidification .. Recycling of precipitate " Thickening of precipitate The basic chemistry has been applied previously, and has also been the subject of two patents (American Cyanamid Company, 1965, Potter et al., 1986). The process involves the conversion of all free and WAD cyanide in solution to hydrocyanic acid by acidification of the tailings solution to pH :s,4, and the conversion of all copper in solution to cuprous sulphide (synthetic chal­cocite) by the addition of a sulphide salt:

Jan 1, 1998

By R. E. Simpson

Beginning in 1972, fully grouted resin bolts were used in underground mines. An estimated 20 million resin bolts will be installed in 1980 owing to their apparent support improvement in most roof-bolt applications. Inorganic cements were tested to replace the resin at a lower cost while retaining the advantages of a grouted bolt. Although other inorganic materials were considered, all but portland and gypsum cements were rejected for reasons of availability, performance, or cost. Portland and gypsum-type cements were tested by the Bureau of Mines to select a fast-hardening, low-cost material that would anchor a roof bolt adequately to meet safety standards. An alpha-gypsum cement, accelerated with potassium sulfate, was selected as the best material because it had adequate pull strength at a desired set time of less than 5 minutes and was readily available.

Jan 1, 1980

By A Takahashi, Y Uchisawa, M Hayashi, T Watanabe, M Susa

Owing to the deterioration of iron ore, the Al2O3 concentration in iron ore increases, and thus it is important to investigate the effect of increment in Al2O3 concentration on the microstructures of iron ore sinters. During the sintering process, a melt is present in the sinter for only a few minutes, and therefore the microstructure of the sinter doesn’t reach thermodynamic equilibrium. Nevertheless, the formation process of the microstructures can be interpreted and predicted to some extent from the equilibrium phase diagram. This study investigated the liquidus isotherm in the CaO-SiO2-Fe2O3- 5 mass% Al2O3 system at 1240°C in air and the phase equilibria of silico-ferrite of calcium and aluminium (denoted by SFCA) and SFCA-I by XRD (X-ray diffraction analysis) and electron probe micro analyzer (EPMA). The following results were obtained: 1. The ferrite melt region with a high Fe2O3 concentration shifts to the lower Fe2O3 side than the liquidus isotherm in the CaO-SiO2-Fe2O3 system. 2. The compositional region of SFCA extends in the CaOꞏ3Fe2O3-4CaOꞏ3SiO2 direction than the silico-ferrite of calcium (denoted by SFC) composition region with a 0 mass% Al2O3. 3. SFCA-I is observed in the present system, which suggests that the increment in the Al2O3 concentration contributes to the stability of SFCA-I. These results imply that an increment in Al2O3 concentration in iron ore leads to a decrement in the volume fraction of the bonding phase and that the fraction of the SFCA phase increases, and those of 2CaOꞏSiO2 and slag phases decrease in the bonging phase. The SFCA-I phase is also precipitated from the slag with an Al2O3 concentration around 5 mass%.

Jun 19, 2024

By Haydn H. Murray

Since the advent of machine coated paper in the mid 1930's, the kaolin industry has had a remarkable growth, In 1935 the domestic production of kaolin was 500, 000 tons and in 1970 the estimated production was in excess of 3. 5 million tons. The process industries which use kaolin most extensively are paper, rubber, paint, ceramics, plastics, catalyst manufacturers, ink, and pharmaceutical. The paper industry is by far the largest consumer of kaolin using approximately 70 per cent of the total tonnage mined and beneficiated. Up until 1970 the major kaolin producers were able to expand rapidly enough to supply the demand but for the first time in thirty years the demand is expected to be in excess of mining and beneficiation capacity through at least 1975. The major reason for this is the expansion of coated paper production in Europe and Japan. Two areas supply the lion's share of kaolin for the world markets. These are the Cornwall area in extreme southwestern England and a limited area of Georgia and South Carolina in the southeastern U. S. The English kaolins are primary - (found in decomposed granite) whereas the Georgia-South Carolina kaolins are secondary - (found in lenticular, continuous beds in the Tuscaloosa formation of Cretaceous age. ) The English kaolins are mined by hydraulic methods whereas the Georgia-South Carolina kaolins are mined by dragline or shovel and benefidated by using a wet process for the majority of the production and/or a dry

Jan 1, 1971

By Kamran Esmaieli

Open Pit Mining Through Underground Voids: Challenges Main Challenges/Hazards: Unexpected collapse of the pit floor and/or pit walls; The loss of equipment and/or people into underground voids; Loss of explosives from blast holes that broken through into the underground voids. How to address these challenges? An important step that must be integrated into mine planning and design is the accurate detection and delineation of underground voids. (i.e. probe drilling, Geophysical techniques, laser scanning,?); Leaving a pillar of adequate thickness between the working bench and the underground voids; Backfilling the underground voids from surface using vertical or inclined raises; Monitoring the working locations (pit floor and pit slopes) to detect movements.

May 1, 2013

By Alan Christopherson

Nearshore construction projects often require installation of steel piles and specific methodologies of installing piles may adversely affect nearby species of concern. Water is an uncompressible medium which allows for easy transmission of energy through the water column. Energy transmission through water depends on the following factors for pile driving: 1) direct contact of the pile and the water; 2) the depth of the water column; 3) the size of the pile; 4) type of hammer; and 5) the energy of the hammer. Seasonal restrictions are usually the best practicable alternative for reducing habitat impacts when pile driving activities may adversely affect the species of concern. When seasonal restrictions are not practical other options need to be evaluated, including mitigation and noise attenuation devices. The broad array of mitigation options will not be discussed as part of this presentation but instead will focus on noise attenuation technologies. Dewatered cofferdams can be effective noise attenuators as they eliminate direct contact of the pile with water while driving. Also, introduction of a compressible medium, like air, near the energy source can provide sound energy attenuation. An unconfined bubble curtain is relatively inexpensive but is not effective in tidal marine projects or rivers and may have unacceptable secondary effects. Secondary effects must be evaluated as these can increase exponentially for larger projects. Secondary effects to the environment include air quality degradation from air compressor use, transportation costs for fuel and equipment, and the potential for injecting oily compressed air into the water column. The confined bubble curtain works well in nearly all environments. It usually is more expensive initially, relative to an unconfined air curtain, but there is less potential for harmful secondary effects. Generally, seasonal restrictions will be adequate to protect species of concern. However, there are conditions in which mitigation or one of the sound attenuation options should be utilized. Site specific factors, including the amount of energy being imparted into the environment, sensitivity of the species of concern, current, accessibility, length of time needed to complete the project, and the cost of the sound attenuation, should be factored into the permit evaluation.

Jan 1, 2013

By K. F. Unrug

The method of coal pillar design involves primarily two aspects, the geometry of the pillar and the strength of the coal. However, the strength of the coal has to be emphasized with respect to the entire pillar dimension rather than isolated strength values of coal samples taken and measured from different locations. The presently applied pillar design systems do not specify clearly what the coal sample strength really represents. The intention of this paper is to introduce the concept of seam strength as opposed to the current practice of using coal strength as a prime design criteria in the formulation of pillar calculations. Seams are most of ten composed of multiple layers of coal, partings, and bone in different configurations, changing within the vertical section of the seam even in relatively close locations. The difference in strength between the weakest and strongest component of the coal seam could be as much as five times or more. An experimental approach based on multiple compressive tests performed on coal samples from the Coalburg and the Warfield seams from Eastern Kentucky was undertaken. The analysis of the results lead to the conclusion that for pillar calculations both the weighted mean of the seam strength and the strength of the weakest stratum should be considered rather than the relatively vague aspect of coal strength The design of pillar dimensions based on the above mentioned aspects should assure a more realistic design performance.

Jan 1, 1985

By Joseph B. Umpleby

WHEN the Cushing field flooded the oil market in 1914 and 1915 with a daily output equal to nearly one-third of the world's production, the situation was soon corrected by increased consumption, and the price of crude oil rose from 45 c. per barrel in, February 1915 to $1.10 in December of the same year-the highest price paid in the Mid-Continent field up to that time. The intensive search for oil during the following seven years failed to disclose a single new ,field equal to Cushing, and many observers concluded that the rapidly increasing number of wells contributing to the world's output, each declining roughly 20 per cent. a year, combined with the rapidly increasing con¬sumption of petroleum, made it highly improbable that any field would; be found again sufficiently large to seri¬ously affect the oil market. That seven exceptional fields should then be discovered simultaneously is a remarkable coincidence. Long Beach, Santa Fe Springs, and Powell, each exceeded Cushing in daily output and reached the apex of their production during a year when Burbank, Tonkawa, - Smackover and Huntington Beach each contributed several times the daily output of the average new pool. This unexpected and tremendous flood of flush production could only have the effect of depressing price and greatly adding to stocks throughout the country. It was particularly depressing in the Mid-Continent as the new oil from California proved of attractive refining grade and because of cheap transportation by water easily undersold Oklahoma crude in the eastern markets.

Jan 1, 1924

By Guillaume Blanc

The development of marine mining in the offshore areas adjacent to most of the insular and continental European States is limited by the complex and evolving nature of its legal regime on the basis of the relevant applicable international, European and domestic rules. As the development of marine mining requires investments in capital-intensive technologies, the bankable feasibility of marine mining projects is very much dependent on the legal security of mining rights, assets and operations in offshore areas. This is quite difficult to assess due to the constant accumulation of applicable and potentially conflicting international and domestic laws in these areas, in particular the coastal zone, the territorial sea, and the Exclusive Economic Zone (EEZ). The often conflicting interaction of international treaties, laws and regulations in offshore areas raises specific and major issues in terms of permitting processes, access rights, ownership rights over the mineral resources explored and mined, flag vs. coastal State jurisdiction over mining vessels and marine mining equipment, international environmental liabilities, and unitisation and multi-forum disputes. In addition, the determination of jurisdiction and the legal regime under which marine mining could take place is becoming even more complex with the development of EU Law and the recent revision of the International Law of the Sea, particularly the new extension regime of the EEZ and jurisdiction over the continental shelf.

Jan 1, 2004

By W. M. Small

From the one producing well in Austria, 7000 bbl. of heavy oil was produced and sold in 1933. This well, owned by the Raky-Danubia, was completed late in 1932 in the formation called Flysch (Upper Cretaceous or lower Eocene) near Zistersdorf north of Vienna. Two wildcats drilling in the vicinity have not yet reached the producing beds. Near Vienna, the European Gas and Electric Co. drilled five shallow wells for gas, three of which were failures. One gas well was completed for 8 million cu. ft. capacity at 260 meters depth and with a pressure of 570 lb. Another is being tested following blowouts. One gas well and one dry hole were completed in the pool in 1932. In Upper Austria, the same company abandoned one wildcat at 679 m. and is drilling at 280 m. on a second. No gas was sold during the year, but a line is being completed to supply fuel to boilers of the Vienna Electric Works. Hungary No deep drilling was done in 1933. Oil and gas concession was granted by Parliament to the European Gas and Electric Co. on Trans-danubia. Active geological and geophysical investigation is in progress. Czechoslovakia In the Gbely and Hodonin shallow fields, some 26 wells were drilled of which three were reported as failures. The total production of the fields was 111,736 bbl. of oil and 40 million cu. ft. of gas used as fuel in the field. At Vacenovice, where there were already two small gas wells, a third producer was completed at 420 m. This pool markets a small amount of gas, which is compressed and used to light railway carriages. Wildcat wells were reported drilling at about 300 m. depth at both Jasina and Telnice. One 700-ni. wildcat near the Hodonin field was abandoned. Another failure was reported completed and abandoned at 820 m. near Holic.

Jan 1, 1934

By Doris M. Hyde

The economy of Belize continued to be relatively unaffected by activity in the minerals sector. Mining production consisted of limestone, marl, and sand and gravel. All production was used for domestic construction projects. By the end of 1979 the major oil companies had, temporarily at least, ceased active exploration efforts. Esso Ventures, Inc., after drilling three dry holes in southern Belize, planned to reappraise its activities. The Reef Exploration, Ltd., concession was acquired by Anschutz Oil Co. (81.25%). with minority interests held by Anglo Oil Co. and Carolina Oil Co. The Anschutz group drilled offshore in the Gulf of Honduras and in Belize Harbor. Echo Exploration has a con-cession along the Mexican border and Spar-tan Petroleum Corp. obtained seven exploration licenses covering 768,000 acres in northern Belize. Spartan's concessions included about 130,000 acres offshore, with the remainder along the southeastern rim of the Yucatan Peninsula. Placid Oil Co. took an interest in the Spartan acreage and became operator. Seismic exploration was underway in 1979. A Mexican company, Pan American Oil and Gas, S.A., was awarded two exploration concessions, one in southern Belize and one near the Mexican border.

Jan 1, 1981

By A. G. Pronk, D. M. Burton

"A regional till sampling program in the Upsalquitch Forks-Tetagouche Lakes area, centred some 70km west of the city of Bathurst, has proven an effective method for gold exploration in the heavily glaciated interior of northern New Brunswick. Prospecting activities within this area over the past three years, have led to the discovery of several gold occurences associated with quartz-carbonate alteration in a variety of intrusive rock types emplaced along major fault zonesQuaternary mapping shows that the glacial history is complex. However, the displacement of material is uniform in distance and direction, and the till is generally thin (0.5 m to 2.0 m) and locally derived, making the interpretation of till geochemical patterns relatively simple for the explorationist. Previous studies have shown the the fin e-grained gold is best detected in the -250 mesh (-0.063 mm) till fraction (clay plus silt) and that the C-horizon is the preferred medium for analyses.Samples were collected on a 2 km grid and analyzed f or Cu, Pb, Zn, Au, Ag, As, Sb, Mn, Fe, Ni, Co, and Cd. Results indicate that concentrations of 10 to 20 ppb Au can effectively delineate areas of anomalous gold in bedrock associated with fault structures, and that a good potential for discoveries exists to the west of the known occurrences, where up to 678 ppb A u has been detected in tills. IntroductionThis paper reports on the result s of surficial geological investigations conducted over the past two field seasons in north-central New Brunswick. The stud y area is located in the Upsalquitch Forks-Tetagouche Lakes map area s (N.T.S. 21 0 19 and 21 0 (10) 70 km west of the city of Bathurst (Fig. I). The area is situated on the margin of the New Brunswick Highlands and has a maximum elevation of 640 m (for a detailed description of the physiography, see Rampton et al. 1984).Historically, exploration in northern New Brunswick has concentrated on base metals within the Cambro-Ordovician Tetagouche Group, resulting in the discovery of man y significant massive sulphide deposits (Brunswick No.6 and No. 12, Heath Steele, Caribou, Armstrong Brook, Orvan Brook, McMaster, Murray Brook, and Restigouche). Auriferous base metal occurrences along the Rocky Brook-Millstream Fault have also been previously investigated."

Jan 1, 1988

By Aiyuan Ma, Tu Hu, Chenyu Sun, Yonggang Zuo, Hongying Xia, Jinhui Peng, Libo Zhang, Yongguang Luo

"In this study, the adsorption characteristics of tannin acid in aqueous solution were investigated using regenerated activated carbon (AC), with the aim to remove the tannin acid organic matter from the solution after zinc hydrometallurgy and Ge precipitation. Results showed the temperature has little effect on the adsorption ability (q.) of the regenerated activated carbon. The experimental equilibrium data were tested for the Langmuir and Freundlich isotherms. The adsorption equilibrium was better described by the Langmuir isotherm (R2 > 0.99). Pseudo first- and second-order kinetic models were used for describing kinetic data. It was determined that the kinetics of tannin acid removal was well fitted by second-order reaction.IntroductionGermanium recovery is a complex processes [1]. Hydrometallurgical processes are favoured and these are based on the precipitation of germanium as hydroxide or sulphide or alternately with tannic acid [2]. However, in the germanium recovery process, too much tannin is consumed by the germanium-tannins complexation process, and results in a high content of tannic acid remaining in solution, which is harmful to the valuable metal recovery [3]."

Jan 1, 2014

By J. J. Pelley

NOT being a scientist, an engineer or a metallurgist, I consider it a very great honor indeed to be asked to address the American Institute of Mining and Metallurgical Engineers. Your program indicates that any lack of intricate and technical knowledge on my part in the field of metals will be well taken care of by others. Therefore, I believe any remarks that I have to make might well be devoted to the practical side of metals in railroad service and to the general railroad situation as I view it today. The experiments now being conducted on the railroads with so-called streamlined, light-weight trains and cars would not have been possible had it not been for scientific and engineering research in the past that made these lighter weight metals available. The railroads now have approximately forty units of these new trains in operation. Experi-ence with them will no doubt be a guidepost for future construction in that direction. While the best known experiments are in the passenger service, they are being extended into the freight service. Within the past three years there was constructed for the Association of American Railroads a new standard box car of ordinary carbon steel, in which, by reason of superior design, weight was reduced by 3500 to 4500 lb. under that of existing cars of like capacity. The Association is now testing a box car that weighs approximately six or seven tons less than practically all of the box cars of like capacity in service today. If these tests are successful a very large field for the use of lighter weight metals will immediately be opened, provided the costs of such metals are not too high. The fact that various experiments are being carried on with other classes of equipment constructed with so-called light-weight and non-corrosive metals no doubt will have a considerable effect upon the rebuild-ing of old equipment. The question then will be: How much can we afford to spend on the rebuilding of an old car weighing six to seven tons more than a new car constructed with the latest available materials?

Jan 1, 1936

By Anand Bhagwat

Surface control can prevent the falls of ground between primary roof support systems and rib support. Using existing industrial products, and adopting them for mining applications, has historically attained surface control in underground mining. However, the latest innovative solution, a revolutionary wire mesh product, is designed specifically for underground mining applications jointly by Bekaert and Orica. This knotted wire mesh, FlexKnot? 2500 and FlexKnot? 3500, uses smaller gauge, higher tensile strength wires, than a chain link fence or welded wire mesh. The higher tensile wire enables the mesh to achieve greater ultimate load-bearing capacity, with significantly lower overall weight. Test results, obtained at the National Institute for Occupational Safety & Health (NIOSH) Mine Roof Simulator facility, illustrate the comparisons of the new FlexKnot with traditional 8- and 10-gauge welded steel mesh. The FlexKnot is superior in deflection, load-bearing capacity, and stiffness?categories that are critical in achieving safer surface control. It also offers enhanced corrosion resistance because of the galvanized coating applied on the individual wires prior to the knotting process. Case studies from underground coal mine installations confirm that FlexKnot has the ability to significantly reduce installation cycle time and to minimize use and repetitive manual handling of individual mesh panels. An added advantage is the ability to supply FlexKnot in rolls for quick and easy handling for either rib or roof support application. When using rolls, the bolter can install the entire roll with one continuous forward motion, unlike the wasteful back and forth travel for mesh panel.

Jan 1, 2014

By Zou Dingxiang

Rock blasting in the project of “Site Formation and Associated Infrastructure Works at Choi Wan Road and Jordan Valley” is the largest urban blasting project in the history of Hong Kong and also is rare in the world. More than 6.2 million of in-situ rock has to be excavated by blasting. The site is located in the center area of eastern Kowloon peninsula, surrounded by highways, registered cut slopes, high-rise residential buildings, MTR subways and the public utilities. The complex situations bring great difficulties and risks to the blasting works. A bird-view photo of the site is shown on Picture 1.

Jan 1, 2007

By Chris Castle

Following the recent award of a prospecting license by the New Zealand Government, Widespread Energy Ltd. (Widespread) is focused on the acceleration of its exploration program in order to bring a potential phosphorite deposit to market in the near future. Rock phosphate is the primary constituent of most fertilizers that are manufactured and distributed in New Zealand. Field trials in the 1980s demonstrated that direct application of rock phosphate can result in a more effective fertilizer (than super-phosphate) with less environmental damage from run-off. At present virtually all of the rock phosphate used by the New Zealand fertilizer industry (approximately 1 million tonnes a year) is imported from Morocco. In recent years price increases of up to 12 fold (peak of $500/t) with massive increases in freight costs have bought to the forefront the economic opportunity to in part replace foreign imports with a local source of phosphate. The Chatham Rise phosphate deposits are relatively well understood, having being discovered during the 1950?s and it is estimated that approximately 100 years supply (at current requirements) is present at shallow depths. An estimated 100 million tonnes of rock phosphate is present within the license area based on previous private and publicly funded research. Widespread has engaged several parties to assist in the exploration planning to confirm the resource potential. Widespread has commenced investigating the feasibility of recovering the phosphorite nodules off the sea floor, and presently has several conceptual technical solutions under consideration and will advance the discussions with potential contractors during the exploration phases. Widespread is acutely aware of its responsibilities to conduct both the exploration program and extraction of the rock phosphate, in a manner that causes minimal disruption to the marine environment. To this end, the National Institute of Water and Atmosphere (NIWA) ? a New Zealand Crown Research Institute has been engaged to assist in designing sampling and extraction methods that will minimize disruption to the seabed. All sampling and extraction activities are planned to be conducted with reference to the environmental guidelines published by the International Marine Minerals Society ?Code for Environmental Management of Marine Mining.? Widespread is conducting its project with a background of changing regimes to both the allocation and environmental management of its activities.

Jan 1, 2010

By P. Sharma

Longwall panels facing wind blasts have been investigated at both Newstan and Moonee Collieries in the Newcastle Coalfield under the Wind Blast Project of the School of Mining Engineering, The University of New South Wales. The fluid mechanics involved in the compression and expulsion of air during wind blasts have been defined and the overpressure and air velocity time histories utilized to determine the wind blast parameters and define the relationship between them. The characteristics of wind blasts pressure pulses in mine roadways show some similarity with transient phenomenon like air blasts from explosives and shock waves from the failure of pressurized vessels. The peak wind velocities in roadways, however, exhibit marked deviations from theoretical predictions based on compressible fluid flow and Rankine-Hugoniot relationships applied to goaf air displacement and panel geometry. Peak overpressures and wind velocities have shown a positive correlation with the areas of goaf falls, with the values peaking off for larger areas. The field investigations have helped the mine management in risk assessment and in evaluating the success of induced caving by hydrofracturing to mitigate the hazard.

Jan 1, 2004