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By Uusna S, Canning R. G, Goodheart B. A

The development of a process for removal of iron oxides from ilmenite is outlined whereby the Ti02 content of Western Australian ilmenites can be upgraded from 55 to approximately 90 per cent. In the first stage, the iron oxides are reduced with solid carbon (coal) to metallic iron. Experimental reductions were carried out in crucibles, a fluidized bed, and a small pilot plant rotary kiln. The reduced ilmenite was then agitated in aerated water, in the presenceof catalysts, so that the iron "rusted" away from the ilmenite grains and the precipitated iron oxide was easily separable by decantation.The influence of variables on the rates of reduction and oxidation are discussed. The oxidation rate was examined for both the physical oxygen transfer characteristics and electrochemically by reference to Pourbaix diagrams, in which redox potential is plotted against solution pH.The upgraded ilmenite is expected to be an attractive material for pigment manufacture, and the iron oxide has prospects of being a marketable by-product. The process may possibly be applied to other ores.INTRODUCTIONThere are extensive deposits of ilmenitic beach sands, Le. iron titanium oxides of the general formula FeTi03, 'occurring in the lower south-west portion of Western Australia, and although there has been considerable commercial development, local producers face keen competition on a freight-cost basis. Thus the removal of the unwanted iron oxide constituent would have the double advantage of reducing the freight differential and presenting a more attractivematerial to pigment manufacturers.

Jan 1, 1965

Recently discovered Carboniferous bentonites are variable in charadeI and thickness, but being altered aeolian, ash-fall tuffs, they are probably extensive. Most are the Ca-montmorillonite type without the natural swelling characteristics of the Wyoming deposits, but their situation, thickness, and response to beneficiation through cation exchange may give them some potential as sources of future economic deposits.INTRODUCTIONLoughnan and See (1959) gave an account of bentonites and fuller's earth deposits of New South Wales. The most likely potential industrial sources were those occurring in the uppermost formations of the Newcastle and Singleton Coal Measures (Permian) in the Hunter Valley and deposited during epochs not marked by strong contemporary vulcanicity.One feature of the record of known occurrences at that time was the absence of bentonites from the thick volcanic sequences of the Carboniferous, but since this paper appeared, many bentonite beds have been discovered by the writer in the Carboniferous facies formerly known as the "Kuttung Series".The purpose of this contribution is to report briefly on the occurrence, genesis, mineralogy, and economic potential of these deposits which augment possible sources of bentonite near major industrial centres on the eastern seaboard.The potential world demand for bentonite would increase markedly with the trend to pelletization in the steel industry, if its use in this field became more general. More detailed mineralogical studies will be presented in later publications.STRATIGRAPHIC DISTRIBUTIONBentonite occurs at irregular intervals throughout a thick sequence of dominantly continental, plant bearing strata...

Jan 1, 1965

By G. E. Perry, R. D. Seba

The steam soak process is the most widely applied and most successful thermal supplemental recovery process in use today. This process, which consists of injection of steam in various quantities into a well that is subsequently used as a producer, can be repeatedly applied to the same well. The treatment, if successful, will increase the production rate of the well for a given period. For this reason, the steam soak process should be considered primarily as an acceleration method rather than as a method for producing oil that could not be recovered by primary means. However, application of this process to reservoirs containing viscous crude may produce oil that otherwise would have zero present value or would be produced at such low rates by primary methods that it would not be profitable. A major necessity for the successful application of the steam soak process is a source of natural energy. This source of energy may exist in one or more of the following forms: expansion of fluids, compaction, gravity drainage. This study was undertaken to determine the effect of gravity drainage on steam soak production and recovery and to develop a method for predicting production rates, ultimate recovery, and heat requirements when applying this process to a reservoir in which the primary driving mechanism is gravity drainage. (For additional discussion of some of the factors that affect recovery of viscous oils by the steam soak process, see Ref. 5.) Model The model developed for analyzing the performance of the steam soak process in gravity drainage reservoirs is a modified form of that developed by Matthews and Lefkovits.1,2 The model used in this study consists of two concentric cylindrical volumes of productive formation with cap and base rock of impermeable material. The inner cylinder, extending from the radius of the wellbore to some predetermined radius, is referred to as the hot zone; and the outer cylinder extending from the exterior boundary of the hot zone to the outer drainage boundary will be referred to as the partially heated zone. Fig. 1 is a schematic cross-section of the model, indicating its thermal properties. Horizontally the reservoir is divided into two regions, the upper region having a high gas saturation and residual liquid saturation, and the lower region containing a high liquid saturation. The boundary between these two regions is referred to as the free surface, which drops and changes shape as fluid is produced from the reservoir. The model was used to analyze the steam soak process by applying the following assumptions: 1. The horizontal formation is composed of one or more homogeneous noninterconnected layers containing incompressible fluids. Each layer is treated separately. 2. The hot zone is heated by the initial soak and is maintained at the steam temperature corresponding to atmospheric pressure by resoaking. 3. The height of the free surface at the producing well is at all times zero (producing well is pumped off). 4. The position of the free surface at the start of

Jan 1, 1970

Paper presented at the Mining Institute of Scotland's annual general meeting held in Glasgow, 8th April 1916. Although there is nothing novel or difficult about the sinking described, circular shafts are not numerous in Scotland so the details connected with such a sinking may be of interest. The shaft was sunk at Dykehead Colliery, Larkhall, which has been worked for over 50 years from the upper seams. It became necessary to sink another shaft to serve as a replacement downcast, by which the output might be maintained and some of the lower seams won. As the sandy clays regularly caused bulging into the rectangular shaft and sinking of the surrounding ground it was decided to make the new shaft circular and to enclose its mouth in a foundation-block of concrete resting on the solid clay. Details are given of the sinking, brick seating and lining, kettle strike, water-rings and doorhead lintels as well as the permanent fittings, winding gear and the cages themselves

Dec 1, 1916

WITH the exception of the deposits of the Milburn Cement Co near Dunedin, Wilson's Portland Cement Co., on the Mahurangi River (a short distance north of Auckland), and those of the New Zealand Portland Cement Co., at Limestone Island, the cement. Tesources of New Zealand remain practically undeveloped. The Milburn Company utilizes a mixture of limestone and mud for the manufacture of cement, while Wilson's and the New Zealand Portland Cement companies both have the advantage of a natural cement stock which requires but small additions of highgrade limestone to give the mixture required. The plant and deposits of the New Zealand Portland Cement Co are located in Whangarei Harbour, some six miles from thetownship of Whangarei. The works and dwelling-houses are situated on Limestone Island, which, with an area of 92 acres, and rising to a height of 212 ft., supplies the bulk of the raw material required. In addition to the island, the company possesses a high-grade limestone area of, roughly, four acres, situated on the mainland, 11 miles to the south. A better location for a cement works could not well have been chosen. On the east side of the island there is a deep channel, which never shows less than 18 ft. of water alongside the company's...

Jan 1, 1912

THE following notes were accumulated during the years 1905 to 1911, when the writer was employed at Stannary Hills. The writer's duty took him over the underground workings daily. In odd moments the geology of the surrounding country was worked out. As the time for this purpose was limited, many interesting points had to be left, untouched. The faulting system in the mines was of such a puzzling character that it seemed as if the geology of the surrounding district might throw some light on it. Dr Jack, in 1907, reported on these mines for the shareholders, but came to no definite conclusions. Unfortunately, the writer has not had access to this report for many years. At the time of his visit the larger develbpments in the Ivanhoe and, Kitchenen orebodies (see Fig 1, B2) were only being opened up. Mr. H. Herman mentions Stannary Hills on p 320, Proceedings Aust Inst ME, new series, No 14, and on p 326 expresses the opinion that the pipe or joint-veins (as at Irvine bank and Stannary Hills) were more valuable to follow than lodes in the granite in that district.GEOLOGY OF DISTRICTThe main feature of the area mapped is a band of altered sedimentary rocks which carry no fossils. It is a mile wide, and consists of a hard band of greywackes 200 ·t ·300 yds. wide, flanked on both sides by contorted shales which become more micaceous as the granite-area to the east is approached. The strata have a general strike of N. 30° W., with a steep westerly dip. A large area of acid intrusive rocks occurs to the west of this band. The outstanding feature of the district is a fault which cuts the sedimentary series in two, to the...

Jan 1, 1918

On the basis of field observation, four principal styles of hydraulic breccia are recognised, and their characteristic features noted. In practice, hybrid styles are most commonly encountered. Numerous examples will be illustrated during the oral presentation, and the potential for definition of a formative environment is emphasised. In one example presented, it is suggested that more than 50 episodes of hydraulic fracturing can be recognised. In all cases at least sane useful conclusions can be drawn in the context of modeling for drill targets.

Jan 1, 1987

By M Begbie, R J. Norris, D J. MacKenzie

The Otago Schist is crossed by numerous deformation zones that formed in the latter stages of metamorphism and uplift of the metamorphic belt. These deformation zones are long (tens of km) linear features at the regional scale, and are generally narrow (km scale or less). Many of these structural zones separate schist domains with different rock types and structural/metamorphic histories. The Hyde-Macraes Shear Zone is one such deformation zone, and this zone hosts the active Macraes gold mine. The Rise & Shine Shear Zone, 80 km NW of Macraes, is also enriched in gold and has been mined historically. Mineralisation in both these shear zones occurred during the transition from ductile to brittle deformation as the schist belt was uplifted from greenschist facies metamorphic conditions. Recrystallisation of quartz and micas in the early stages was overprinted by cataclasis, with sulfide and gold precipitation throughout. Many of the other late metamorphic deformation zones formed under similar greenschist to sub-greenschist facies conditions, with similar overprinting of recrystallisation textures and folds by more brittle textures such as breccias. Under these conditions, originally regionally pervasive deformation at the highest metamorphic grades was evolving towards more focussed high strain zones at lower temperatures and pressures. Shear zones initially focussed fluid flow along microshears and mineral grain boundaries, resulting in 1 to 100 m scale alteration and replacement in the host schist, with only local development of quartz veins. Fluid flow was not controlled by open fractures, and the rate of fluid movement was probably slow and pervasive. After uplift into the brittle regime, the schist belt underwent tectonic extension. Extension was accompanied by development of swarms of steeply dipping veins, with localised mineralised normal faults. Hydrothermal fluid flow throughout this uplift history was a normal consequence of late stage devolatilisation of the metamorphic belt. Hence, all late metamorphic deformation zones should be considered prospective for gold accumulation.

Jan 1, 2005

By G. K. Jorgenson, S. H. Chung

"IntroductionThe SABREX Blast Modelling Program was developed jointly by the companies of the ICI Explosives Group, of which C-I-L Inc. is a member. SABREX (Scientific Approach to Breaking Rock with Explosives) is a modular computer program which incorporates new technology with a number of tested programs that have been in use world wide.SABREX predicts the performance of blasts in terms of (I) fragment size and distribution; (2) muckpile profile and face velocity; (3) grade fracture; (4) collar breakage; (5) a rupture envelope which depicts crack penetration behind and beneath blastholes; and (6) a complete cost analysis including explosives, drilling and accessory costs. The predicted blast results are displayed as dynamic colour graphics and in tabular form.SABREX uses data on the detailed geometry of the drilled and loaded pattern, detonation characteristics of the explosives and the dynamic properties of the rock to generate blast predictions. SABREX blasting calculations take into account the effects that shock and quasi-static pressures exert on the rock around the blastholes. While physical effects occur very rapidly in rock blasting, it is possible to view and model the sequence of events as discrete sections.The program can be run on a microcomputer and is currently operated by C-I-L technical service staff in Canada for the use of drilling and blasting operators.Figure I is a diagram representing the modules of the program and associated technology that is used to complement the program.Any, or all, of the modules may be used in a particular study or blast optimization. Because the BOBCAT module of the SABREX program has been described in previous papers(7.8.9), this discussion will concentrate on the newer modules: CRACK, HEAVE, RUPTURE ENVELOPE and to a limited extent, KUZ-RAM, which present a more detailed picture of the blasting process.Each of these modules is discussed in terms of the information they offer the operator in analyzing the blast. Specific examples of recent usage in Canadian mining situations are included to illustrate the ability of the model to produce practical results that can assist in optimizing actual blasting operations or solving problems that do exist."

Jan 1, 1987

By J. Adkins

This document presents a description of the results of a project aimed at producing a broad description of current mining training programs and an evaluation of their effectiveness with respect to reducing mine injuries. Aggregate training and injury data were used to evaluate the overall training effort at 300 mines as well as specific efforts in twelve categories of training course objectives. From such evaluations, recommendations were derived with particular emphasis being placed on identifying program characteristics that tend to be associated with effective training. Recommendations were also formulated with reference to role changes in industry and government interaction with respect to training programs, new or additional training programs, changes in the types of course materials and training methodologies, and recommendations concerning new areas for investigation.

Jan 1, 1976

By O. E. Palasvirta

Several drum-type, low-intensity dry magnetic separators have recently been described 1,2,3,4 all of which share at least two generic similarities. The magnet consists of a multiplicity of poles of alternating polarity and, the speed of the drum shell, relatiw to the magnet, is such that the magnetics are agitated through rotation of the magnetic particles around their individual axes. The speed of the drum relative to the magnet (differential speed) determines the frequency of the field reversals. For effective agitation this frequency generally has to be above a specific value, which varies according to the mean particle size of the magnetics. With separators of small diameter, say less than 11/2 ft., a sufficient differential speed for treatment of fine magnetite can be attained only by rotating both the magnet and the drum separately; separators of large diameter may attain sufficiently high differential speeds with stationary magnets. Separators of large diameter thus have the advantage of simplicity of design. The capacity of a separator of this type is directly proportional to the speed of the shell. As the centrifugal force opposing the magnetic force increases at a slower rate than the peripheral speed of the shell when drum diameter is increased, large drums can be operated with higher peripheral speeds. Thus they have a higher capacity than smaller drums. Separation is also a statistical phenomenon, i.e. the grade of concentrate improves as the number of agitations or rotations of the magnetic particles per separation increases. As separators of large diameter have space for a large number of magnets they are best suited for production of optimum grade concentrate. The statements above are general clues For separator design. In the following an expression IS derived showing a more exact relationship between the pertinent separator variables. As both magnetic attraction and centrifugal forces are directly proportional to the volume of the affected bodies, complications in mathematical analysis, arising from variable particle size, are avoided by considering the force per unit volume of affected material. For the magnetic force per unit volume Runolinna (3) gives the following equation: V " 1 + N(ur, - 1) uo dr (1) where ur and uo stand for the relative permeability and the permeability of vacuum, respectively, N is the demagnetization factor, B the intensity of the magnetic field, and r the distance from the face of the magnetic pole. The permeability of a specific magnetite ore can generally be considered as a constant. For ground, liberated material N can also be treated as a constant, and the first simplification can be made by writing ur-1 1=k1. 1 + N(ur - 1) uD k1. Fig. 1 shows the field intensity curves for two U-magnets of different size, but of roughly similar geometry of cross-section as plotted against the distance from the plane of the pole faces. The curves

Jan 1, 1961

By Silvana Costa

In the last two decades, there have been nearly no new mining towns built in Canada. Governments and mining companies have viewed long distance commuting (LDC), commonly known as fly-in-flyout or fly-in mines, as a way to avoid problems associated with building a new community and providing for its sustainability after mine closure. LDC is also considered more cost-effective than building a mine town. The intensification of the use of LDC in the Canadian mining sector has been quite rapid, particularly in northern regions. However, LDC has implications to employees, their families and communities, which deserve further examination, particularly considering the significant expansion in Northern mining and Aboriginal participation in this sector. This paper presents a review of the major issues in long distance commuting, both from an industry and community perspectives. It is a result of preliminary investigation for a PhD research project that will be pursued by a Bridge Fellow and UBC Mining Sustainability Working Group member, and guided by an interdisciplinary research team at the University of British Columbia (UBC). The Bridge Fellowship Program is research-training program linking the UBC?s Faculties of Medicine, Engineering and Graduate Studies. Its mission is to develop creative evidence-based prevention measures for public, environmental and occupational health problems. The SWG is an interdisciplinary student group based in the UBC Department of Mining Engineering, committed to respond to the complex sustainability-related challenges currently faced by the mining industry. In other to pursue this project, it is paramount that industry and local communities alike participate in the development and clarification of research questions as well as in the research design. It is hoped that this paper will function as an invitation for industrial and community partners for such study. The main themes identified for this research are occupational health and safety of LDC employees, family life impacts and community health impacts of this model of resource development.

May 1, 2004

By C Vuillier, A Roshdieh

Water is the main medium for removing impurities from iron ore during wet processing to achieve a higher quality product. However, there is a substantial increase in freshwater consumption due to an increase in demand from the following two factors: in the past 55 years the world population has doubled from 3 to 7.5 billion and crude steel production has increased five times from approximately 350 to 1662 Mt/a (IISI, 2008). Furthermore, social development in developing countries exacerbates water consumption making freshwater an increasingly valuable resource with an average distribution of 70 per cent for agriculture, 20 per cent for industry and only ten per cent for domestic consumption (Hourtolle, 2005; OECD, 2009). Rapidly changing regulations over the access and preservation of water across the world indicates the growing importance of this issue, so the mining industry must adapt to this continual change and must be committed to increasing the efficiency of water usage.Tailings dams receive most of the water used by the process plant. In arid regions where evaporation is high and availability of water low or non-existent, technical solutions other than the conventional tailings dam, such as thickened and/or filtered tailings, exist to optimise the recovery of water and reduce the need for external water consumption. However, these solutions present additional challenges, such as energy consumption and transportation from the process plant to the ultimate storage area.This paper considers a range of alternatives covering thickening and filtering, transportation and storage, water return, closure and rehabilitation. Mining projects in the future will be more affected by the rising cost in water and tighter regulations in accessing water and energy. Good tailings management can contribute significantly to reducing the dependence on these two key commodities (water and electricity), improving the resilience of iron ore projects especially in arid regions and areas with high competition for water.CITATION:Vuillier, C and A Roshdieh, A, 2017. Minimising the water loss associated with mine tailings disposal, in Proceedings Iron Ore 2017, pp 245–250 (The Australasian Institute of Mining and Metallurgy: Melbourne).

Jul 24, 2017

By M. J. Blattman

Upon completion of an underground mine design, the planning engineer is faced with a surprisingly complex problem, “What development and mining sequence should be implemented so as to maximize the return on investment?” The problem relates to the scheduling of development headings to access stope production areas in such a way that the most money is made as quickly as possible for as long as possible. The total dollar value of the stopes, the average grade, the total tonnage, nor even the profit margin do not accurately give an indication of the “proper” mining sequence on their own. This paper will outline a method being developed by the author that can create a sequence of events that maximizes the net present value (NPV) of a given development and production design using information already being generated during the design process.

Jan 1, 2003

By Y. K. Wong

This paper describes in detail various problems concerning the construction of a pile-raft foundation supporting a 42-storey tower block. The subsurface generally consists of highly weathered sedimentary rock. A comprehensive instrumentation program is implemented to monitor the behaviour of the foundation system throughout the construction period of the superstructure. Instrumentation observations are highlighted in the second half of the paper.

Jan 1, 2010

A review is made of the limited published experience of the effects of cemented fill in flotation.A general approach is adopted in listing and discussing possible sources of, and reasons for, ore contamination by cemented fill, together with basic, fundamental approaches to minimizing this contamination. These approaches involve basic mining design, effect of fill placement density, optimization of curing time and of cement content, variation of fill particle grading, use of flocculants and of pozzolans, fill placement and dewatering, and or blasting and handling practice.

Jan 1, 1974

By W. J. Verner, J. R. Lucas

Billions of tons of bulk solid materials are processed through our industrial plants each year, and the tonnage is steadily rising. It has been estimated that for every dollar spent in industry as a whole, approxinlately 30 cents is consumed in the handling of bulk solid materials. It is in this category that tremendous savings are possible through the use of improved techniques. Since World War 11, the mining, steel, chemical, and grain industries, among others have made use of increased materials-handling automation in order to gain some of these savings. However, in a chain of automatic operations, every link must be completely reliable, for if there is a single failure, the whole system immediately becomes ineffective. Only too often the weak link in the chain proves to be the flow of bulk solids from bins. To contribute to the fundamental knowledge in this area, a research study has been continuing at The Ohio State University. The principal objective of the investigation has been to study the internal stresses existing in confined bulk solids. LITERATURE SURVEY Literature studies have revealed that many outstanding people have made contributions to the field of bulk solids. For instance, C. F. Jenkin,1 suggested: a. The pressure on a bin wall is not directly proportional to the depth beneath the surface of material in the bin. b. The vertical pressure distribution on the base of a bin is not actually uniform but is a variable. c. Arches form in bins as a result of very small deformations of the material in the bin. This deformation causes a series of gaps to appear, and consequently causes the disappearance of diagonal forces that cannot act across these gaps. The removal of the diagonal forces causes horizontal forces to be introduced which seem to be the chief cause of arching. 11. A. Janssen,4 in 1895 in connection with his experiments on bins, derived a differential equation to describe both the lateral and vertical pressure in bins with vertical sides. This represents a significant contribution to bulk solid theory, and thus its solution is reproduced as follows: L = KV = RW/U' [l-e -U'KY/R] I where L is the lateral pressure of the bulk solid in psf., V is the vertical pressure of the bulk solid in psf., K is the ratio of the lateral pressure to the vertical pressure at any point, R is the hydraulic radius of the bin in feet, W is the density of the bulk solid in lbs. per cubic feet, U' is the coefficient of friction between the stored material and the bin wall, and Y is the head of material above the point in question in feet. In 1903, Jamieson,6 in an elaborate series of experiments on full sized bins measured vertical and lateral pressures by hydraulic diaphragms. He determined many values for mediums of corn, wheat, peas, and flaxseed. In 1951, Caughey, Tooles, and scheer3 measured both lateral and vertical pressure in deep bins by using strain guages on steel bands. Values were calculated for cement, gravel, sand, soy beans, shelled corn

Jan 1, 1961

A short account is given of the theory and practice of determining the true U3O8 content of ore samples by the determination of the beta and gamma activities separately, using the method of Eichholz and his associates.It is shown that, despite the variation of sample activity without change in U3O8 content, the true U3O8 value can still be found.Thorium can be determined simultaneously if this element is also present.

Jan 1, 1957

By Mark H. Balfe

Over the last decade, Fenway Park has undergone annual improvements to modernize the facility for players and fans. These renovations include the Monster Seats, the Right Field Roof expansion, a new pavilion behind home plate, expansion of the Red Sox clubhouse, additional roof seating, and concourse improvements. Retrofitting the historic ballpark to bring it up to current standards required installation of foundations to support the new structural loads for each of the alteration projects. This required evaluation of existing conditions, and in many cases augmentation of the foundations at existing columns to accommodate the structural changes to the park. New foundations, generally consisting of drilled-in micropiles, were installed in numerous configurations and conditions. Since 2003, a total of 215 drilled-in micropiles have been installed to augment various columns around the park. The micropiles range in capacity between 40 and 70 tons and are installed through Fill and Organic Soils and embedded into the dense Glaciofluvial Sand and Gravel layer. Issues and learning related to the foundation augmentation include schedule constraints (work is typically conducted during the off-season and schedule is very aggressive), encountering old/abandoned utilities or foundations, ventilation of equipment, and management of spoils during micropile installation.

Jan 1, 2011

By Ray H. S, Galgali R. K

It is well accepted that the blast furnace will continue as the main route for iron-making for many more years. However, its limitations have motivated researchers to look for alternative routes, particularly, those where non-coking coal is used for liquid iron production. Smelting reduction (SR), where coal and oxygen are used to produce liquid iron and power is now receiving serious attention. Several smelting reduction reactors are now operating in pilot plant scale and one or two have reached commercial status.

Jan 1, 1999