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By I. N. Gridasov, T. V. Ignatova, E. V. Shelepov

"Mikhailovskoye Deposit is comprised of oxidized ferruginous quartzites among other minerals with the former widely spread across the ore field and mined along with unoxidized ferruginous quartzites. PJSC Mikhailovsky GOK strategic development is aimed at iron ore product output expansion. The most critical item of the strategic development road map is process design for separation and concentration of hematite contained in oxidized ferruginous quartzites mined as the by-product in the open pit. Laboratory and semi-industrial tests run to design cost-effective, reliable and environmentally friendly process for Mikhailovskoye deposit oxide quartzites processing included the following processes: - pilot tests of reverse anionic flotation which produced concentrate with Fe60.1-62.9% total iron content and 66-69%Fe recovery rate; - combined magnetic separation and flotation (Marubeni Company, 1982) including slime removal, reverse anionic and cationic flotation and high gradient magnetic separation resulting in 48.9% yield, Fe55-57.5%, up to Fe60.5% hematite concentration ( Fe64.1% being the best result achieved),76.2% recovery. - magnetic separation and flotation, including separation in low gradient (1400 Oe) and high gradient (up to 17000-18000 Oe) magnetic field. The results of these pilots tests were the following: 57-59%Fe concentrate, 70%Fe recovery (Mekhanobrchermet, MGOK, 1982-1988): - magnetic roasting in pilot plant of TSGOK (Krivoy Rog) which produced 61.1%Fe concentrate with 81.5% recovery. Major disadvantage of the method is high generation of dust equal to 20% of the initial feed. Based on third-party studies flotation of oxidized ferruginous quartzites process embracing best processing methods was designed by Metalloinvest Management Company LLC and PJSC Mikhailovsky GOK engineers. This paper discusses analysis of studies aimed at intensification of separation processes with application of mechanical slurry agitation (MSA), addition of alkali (NaOH) and elutriation of initial feed. The paper also provides a design solution to implement a lab-scale MSA plant. It includes feasibility evaluation of MSA inclusion in flotation of oxidized ferruginous quartzites process to enable higher yield and hematite recovery in resultant concentrate. Outcomes of the discussed work have significant value for prospective engineering of OFQ concentration process."

Jan 1, 2018

By J Graaf, R A. Murrell

Gold Fields Australia is constructing two major ventilation shafts at the Wallaby gold mine in Western Australia. The new ventilation shafts are required to facilitate the long term ventilation strategy for the mine, thereby allowing continued extraction of ore beyond 1000 m below the surface. The construction work has involved all of the challenges that shaft construction can throw up, including challenging geotechnical conditions, unexpected high water inflows and major circulation loss during pilot hole drilling for raise boring. An extensive geotechnical and hydrological investigation program was undertaken prior to awarding the shaft construction contracts. While most of the risks were identified, several proved to be much more challenging than expected. The shaft construction methods included conventional sinking into the fresh rock profile in each shaft, followed by raise bore pilot hole drilling and reaming. A headframe was constructed for the first shaft, which was sunk to 92 m with a stage suspended in the shaft to facilitate the concrete lining and provide rope guides for the kibble winding. Drawing from experience when sinking the first shaft, additional ground pre-conditioning was implemented for the second shaft, which was pre-supported with continuous piles to 28 m followed by sinking to 50 m using a crane instead of winders and a headframe. Following the conventional sinking through the weathered zone in each shaft, the shafts were completed using a raise bore. The first shaft utilised a riser pipe and rotary vertical drilling system (RVDS) with the second shaft having utilised a dual rotary rig for pilot hole drilling. This paper reviews the site investigations undertaken, construction methodologies applied, the results achieved and the lessons learnt.CITATION:Murrell, R A and Graaf, J, 2017. Shaft construction at the Gold Fields Wallaby mine, in Proceedings 13th AusIMM Underground Operators’ Conference 2017, pp 321–334 (The Australasian Institute of Mining and Metallurgy: Melbourne).

Oct 16, 2017

By D. W. Morgan, K. W. Downes

"OVER half a million tons of chromite ore is used annually on the North American continent, all of which is imported from overseas. Chromite is essential in the manufacture of stainless steel, armour plate, and tool steel, to mention only three important uses. It is, therefore, a strategic mineral, and every effort should be made to discover a means of utilizing our domestic supplies.Both Canada and the United States possess deposits of chromite, but they are low grade with respect both to their chromium content and to the ratio of chromium to iron. Mechanical concentration can improve the chromium content •by rejecting gangue, but chromium concentrate produced is still lower in chromium than imported chromite and, more important, the ratio of chromium to iron is only about half that in the imported material. At present, a chromium to iron ratio •of 3:1 is desired by industry. To obtain this .ratio in the case of domestic ores, a chemical attack on the chromi'e is necessary."

Jan 1, 1952

By Richard Keith Corbin

Canadian junior mining companies whose gold exploration and exploitation programs take them across the border into the western United States should be prepared to deal with the myriad of title issues involved in acquiring unpatented gold mining claims. The purpose of this paper is to serve as an introductory outline for Canadian junior mining companies to mining laws of the United States, as well as to relevant laws of some of the western gold mining states. Topics will include the five w's (who, where, what, why and when) of Canadian junior mining companies1 rights and responsibilities in acquiring interests in U.S. gold mining properties by claim staking, lease or purchase. Historic terms of common parlance among U.S. miners, such as "claimjumping" are defined and discussed. Various legal doctrines, such as "pedis possessio" and "good faith" in the location of claims are covered as well. Controversial subjects of contemporary interest are addressed in some detail, such as whether to locate a bulk-mineable disseminated gold deposit with placer claims or lode claims, and whether lodes may be staked over placers. By thus heightening the awareness of Canadian junior mining companies, it is hoped that they can be properly prepared to avoid title disputes, and to win lawsuits when they are unavoidable.

Jan 1, 1988

By Ashley P, Neale T

Alluvial gold was discovered on Sudest Island in 1888, and by 1893, an official production of 10 000 oz had been won by expatriate miners from shallow alluvial and colluvial workings. Hardrock sources were located and while one was developed at Mt Adelaide, production is unknown. Sudest Island comprises mostly phyllites and lesser coarse grained rocks which are cut by metamorphic quartz veins and basic (locally shoshonitic) intrusives. Sheared and altered basalts and serpent- inites represent are believed to be elements of an ophiolitic suite inferred to be associated with metamorphic core complex development and thus similar to tectonic environments on Misima and the D'Entrec- asteaux Islands. No epithermal-style quartz suggestive of a target similar to that on Misima Island has been identified on Sudest. A hardrock source for the alluvial and colluvial gold is interpreted to be metamorphic quartz veins similar to those in the Bendigo- Ballarat Zone of central Victoria, possibly remobilising gold derived from the meta- sedimentary and meta-igneous rock pile. The present focus is on development of a small scale alluvial gold mining operation in conjunction with exploration for hardrock targets. This latter programme remains at a reconnaissance stage.

Jan 1, 1991

Jan 1, 1967

By B. Yu, Y. O. Oyediran, M. Robart

"This paper presents the latest flotation development testwork conducted in 2015 on the ‘B Zone’ samples from the Strange Lake Alkalic Complex (SLAC). Since the discovery by Iron Ore Company of Canada (IOC), metallurgical development has been under taken by a number of mining companies targeting various value metals, including yttrium, zirconium, niobium, and rare earths.Most recent, Quest Rare Minerals Ltd. (Quest) completed a Pre-Feasibility Study (PFS) in 2013 where the flowsheet was relatively complex and led Quest to explore alternative options. In 2014, the PFS flowsheet was simplified and one of the features introduced was pre-concentration by rougher flotation. The combined rougher flotation concentrate and slimes successfully recovered >90% TREE in 60% mass thus reducing capital cost and technical risks of the downstream hydrometallurgical processes. The latest flotation development testwork focused on achieving a pre-concentrate in which >80% TREE are recovered in 20% mass. Two separate reagent schemes, based on an ester phosphate collector (Clariant 1682) and a benzoylhydroxamic acid collector (Florrea 7510), were developed. Parameters evaluated in the development testwork included desliming, secondary yttrium and zircon collectors, depressants, temperature, conditioning temperature, time, and density, pH, sodium silicate type, cleaning, and flowsheet configuration. Both developed reagent schemes achieved the targeted metallurgy.INTRODUCTIONThe Strange Lake Alkalic Complex (SLAC) was discovered after geological survey and mapping studies by Geological Survey of Canada and Newfoundland and Labrador Department of Natural Resources between 1967 and 1980. Subsequent exploratory drilling programs by Iron Ore Company (IOC) in the 1980s found that the REE and high field strength element (HFSE) mineralization were within the central region of the SLAC which was named A Zone by IOC and later renamed Main Zone by Quest Rare Minerals Ltd. (Quest). Additional exploratory drilling outside the Main Zone by IOC and later by Quest, led to the discovery of B Zone, which was recognized as the most significant deposit of rare earth elements, yttrium, and zirconium in the SLAC. The B Zone Indicated Resources are estimated at 278.13 Mt at 0.93% total rare earth oxide (TREO) and Inferred Mineral Resources are estimated at 214.35 Mt at 0.85% TREO (Oyediran et al., 2014)."

Jan 1, 2016

By H. W. Knott, M. H. Mueller, P. A. Beck, W. P. Chernock

PREFERRED orientation studies by Harris of rolled uranium rods indicated that hot rolling to a small reduction of area caused the (010) planes to become strongly oriented and the (110) planes weakly oriented perpendicular to the rolling direc- tion. The relative intensities of these two fiber texture components were reversed upon rolling to higher reductions of area. Cold rolling caused the (010) planes to become strongly aligned and the (130) planes weakly aligned perpendicularly to the rolling direction. The present investigation was undertaken to explore in more detail the effect on the rolling texture of variables, such as the penultimate condition, the final rolling temperature and reduction of area. In addition, the recrystallization texture of rolled uranium rods was also investigated.

Jan 1, 1959

By Ming’an Wei, Qifu Duan, Chengtie Wang, Jianmin Wu, Erdenet Mining Corporation, Lusheng Zhou, Wenjian Wu

"The development and industrial applications of magnetic liners have been around for decades. A Swedish company SKEGA first introduced the rubber magnetic liner, and then followed by the Chinese metal magnetic liners. Traditionally, both liners were used in secondary and regrind ball mills, especially for ores containing magnetic materials. Mostly steel balls or equivalent forged balls, usually below 60 mm in diameter, were used as grinding media. With the development of mineral resources over the years, SAG mills and larger ball mills have become the dominating components for comminution circuit design globally. Due to the larger ball mills and thus larger grinding balls (up to 80 mm) especially in non-ferrous metal industry, the application of magnetic liners has been very limited. Based on the new development of materials, the HMR Group Limited has been exploring new designs of magnetic liners which led to the invention of the Nano Steel Magnetic Liner (NSML). Recently, NSML had a successful application in a 5.5m x 6.5m ball mill with 80 mm balls at the Erdenet Copper Mine in Mongolia. Although the first set of liner had a service life of 12 months, the design of the second set was modified and improved to accommodate the operating conditions, which is expected to reach least 24 months service life. The original manganese steel liner only had about 8 months liner life.1. IntroductionMineral processing is an essential operation for the development and utilization of mineral resources. The effective concentration of various useful minerals depends on sufficient liberation of the mineral particles in the ore. The crushing and grinding process such as ball milling are the most common way to achieve proper liberation size. Mill liner is an eternal topic for the operations, not only because it protects the equipment, but also affects the mill grinding efficiency and availability. In recent years, magnetic mill liners have been developed that can easily meet the production targets with numerous benefits, such as zero maintenance, reducing specific energy consumption and improving grinding efficiency."

Jan 1, 2016

Polymer electrolyte membrane (PEM) fuel cell has increasingly become the potential choice of zero-emission power source for portable, mobile and stationary co¬generation applications. However, technical barriers need to be overcome before its widespread commercialization; cost reduction and performance improvement including reliability are the two key areas, that can be realized through better cell/stack design and improved understanding of the transport processes occurring inside the individual cells and stacks. In this presentation, we will provide an overview of various cell/stack models that are available in the literature, their strength and weakness, and then present a comprehensive multi-species, multi-phase and multi-dimensional formulation of a single PEM fuel cell, with consistent and systematic formulation for all the regions involved, including the solid bipolar plates, gas flow channels, the electrode backing layers, the catalyst layers and the electrolyte membrane. Such a detailed approach allows us to extract sufficient information to the analysis of a stack of PEM fuel cells. Stack model will be presented that investigates the various stack designs and flow configurations, and the optimal stack design based on the present study will be described. Also some innovative cell/stack designs will be featured.

Jan 1, 2005

By R. A. D. Pattrick, D. A. Polya, D. J. Marsh, J. -J. Bao

"The utility of high-density stream sediment and stream water sampling to the exploration for silver deposits was investigated by the study of the epithermal Ag-Au base-metal prospect at Lagalochan in western Scotland. The geology of Lagalochan is dominated by a calc-alkaline Caledonian intrusive complex emplaced into Dalradian Supergroup rocks (Harris et al., 1988a). The complex consists of subvolcanic porphyrytic rocks associated with intense hydrothermal alteration and brecciation. Early Cu-Ag-Mo-rich mineralization is found in the core of the complex with later Pb-Zn-Ag-Au-As-Sb-rich mineralization toward the margins (op. cit.).Stream sediment sample analysis spatially resolved the Cu-rich and Ag-rich mineralization. Ag and Cu anomalies relative to local background values were found in all size fractions analyzed (-125µm, +125 µm, +180 µm, +250 µm) but the more pronounced anomalies were found in the -125 µm fraction. The coarser fractions generally revealed more erratic but longer dispersion trails. The separation of Cu-rich and Ag-rich mineralization is also apparent in the distribution of relatively high dissolved Cu and Ag in stream waters, particular when expressed relative to the solute load as Cu/TDS and Ag/TDS.The mineralization at Lagalochan is indicated by Ag, Cu and Pb stream sediment and water concentrations that are anomalous with respect to local backgrounds, but are difficult to distinguish from regional backgrounds. This emphasizes the further potential of high-density stream water sampling,in particular, as a viable geochemical exploration tool on a sub-regional scale for epithermal depositsin relatively unpolluted upland terranes."

Jan 1, 1995

A. K. McCosh, Coatbridge, Scotland (written discussion*).-It is well known in Great Britain that oven operators in the United States have been able to reduce the coking time much below European standards by the employment of higher temperatures. Our linings have always been the factor that has prevented our doing the same, and it would be of much interest to coke-oven operators here if Mr. Blauvelt would give a typical analysis of the bricks his company uses for the linings of its ovens, and if he could see his way to send me a sample so that I could have the texture examined, I should personally be very much obliged. The lining brick which my company has found most successful is of a ganister variety, and has the following analysis: Silica, 80.8 per cent.; alumina and iron oxide, .17.8 per cent.; lime, 0.8 per cent.; magnesia, 0.07 per cent.; but with this brick the least carelessness on the gas regulator's part may destroy the lining. It would also be of interest if Mr. Blauvelt could give the temperatures of the air leaving these generators and also of the oven flues.

Jan 10, 1918

By Q. M. Huang

In 1979 our company undertook the project of infra-structural work of White Swan Lake Hotel, (International class ) Guangzhou. Visit to the site showed that it was situated at the riverside, covering an area of 54,000 M2 with 30,000 M2 of which reclaimed from Pearl River. The material used for reclamation was black sand which was dredged from the nearby riverbed. The sand had the properties of high permeability and very low internal friction. The basement of the building was 6.2 m below ground level and 3 m lower than the riverbed. Apart from the pile foundation, a diaphragm wall was to be constructed prior to the commencement of excavation work for basement. A feasibility study was carried out to determine the method of construction which would maximize utilization of the plants and equipment that were available in the execution of the aforesaid foundation works. This report concerns only the construction of the diaphragm wall and the performance of the plants employed. A detailed delineation of the construction method is herein discussed

Jan 1, 2010

In the geologically prospective nations which rim the Pacific Ocean, mineral deposits offer great potential to create wealth for social and economic development. The paper first examines the geological and economic attributes of potential mineral wealth based on current outlook assessment of all significant base metal deposits discovered to 1988 in two Pacific Rim nations - Australia and Canada. The variability of mineral wealth among the economic deposits evaluated and the major contribution of the few world-class discoveries to total mineral wealth are highlighted. Then, the essential but too often neglected linkage between the makeup of potential wealth and its actual realization is analyzed. The impact of taxation and the role of exploration are crucial in this regard. Finally, the ingredients of exploration success, prerequisites for realizing the mineral wealth of nations, are examined.

Jan 1, 1995

By George Carico

Research and related demonstration projects are being conducted in West Virginia on both existing and former coal surface mine lands to determine potential post-mine land re-use options that offer the greatest likelihood of future benefit and success. Examples of projects include renewable energy considerations that incorporate solar, wind, and/or biomass options, and contain components designed to educate business, government entities and the local community on renewable energy options and potential opportunities Multiple property re-use options are being researched and evaluated, based on site-specific conditions and characteristics, including infrastructure, local community needs and regional economic conditions. Re-use options being explored include innovative uses and needs, such as specialty housing, unique business and industrial needs, and an extensive variety of recreational and small business opportunities that best fit the specific needs of the local community and regional economic structure.

Aug 1, 2013

By P. B. Altringer

Searles Lake, CA, contains the largest known domestic tungsten resource. The brines in this near-dry lake bed, located in the Mojave Desert 130 mi northeast of Los Angeles, contain an estimated 135 MMlb of tungsten. However, the low concentration of tungsten (0.080 g/L W03) in the supersaturated brine makes selective tungsten extraction very difficult. Although many brine chemicals are extracted from the lake, tungsten recovery was an elusive goal prior to Bureau of Mines development of an ion-exchange technique. This publication describes the Bureau process. The following subjects are ad-dressed: ? The Searles Lake tungsten resource. ? General problems associated with tungsten recovery. ? Bureau research objectives. ? Synthesis of ion-exchange resins. ? Development of a two-stage ion-exchange tungsten extraction and concentration procedure. ? Product recovery and purification. ? Economic evaluation. Flowsheets for recovering three products (calcium tungstate, sodium tungstate, and tungstic oxide) are presented and evaluated, as well as a summary of the research effort and potential applications.

Jan 1, 1985

By Louis W. Cope

Placer material, regardless of the value of gold, tin, titanium, diamonds or other value mineral it contains, remains worthless until the valuable constituent is separated from the bulk of the material. This separation is no mean task when considering that a gold placer containing 0.01 to 0.03 oz/yd3 of gold, which is the range of grade of typical placer deposits; yes, 1:3,000,000! It is a miracle that gold placer mining has ever been profitable. Added to the situation of minute quantities of gold are several other problems, such as the gold often being very finely divided, the association of boulders and clay, and running and/or ground water. As each placer deposit is individual and distinctive, many factors have to be considered in planning the method for gold recovery from the alluvial deposit. Previous chapters have shown that in the exploration and sampling stage, some knowledge of the amount of each size of coarse and fine material which occurs in the deposit as well as the size distribution of the discrete gold particles is determined. Unless informed to the contrary, as a general rule of thumb, plant designers will consider that 40 percent of the material will pass through a 5/8-inch screen or punched plate hole. Also that there may be an occasional nugget and normally considerable amounts of fine gold. The designer must

Jan 1, 1992

By J. F. Peters

The term solution loss is discussed and defined. Examples are given showing that solution loss may either have a favorable or unfavorable effect on blast furnace performance. A theory is advanced explaining the contradictions encountered during earlier studies of the problem. MANY papers have been written and numerous theories advanced concerning the chemical reactions in the iron blast furnace. Richards, discussing the utilization of fuel in the blast furnace, said: "All the carbon burnt in the furnace should be first oxidized at the tuyeres to CO and all the reduction of oxides above the tuyeres should be caused by CO, which thus becomes CO,. This dictum is not Gruner's own words, but expresses their sense, and from the point of view of the present discussion, it is the correct principle upon which to obtain the maximum generation of heat in the furnace from a given weight of fuel." Richards also said the cubic feet of wind per pound of coke does not express how efficiently a furnace is running, but it will be shown later where Howland paid much attention to this figure. Richards pointed out a shortcoming of Grun-er's discussion in that Richards claimed there is not enough CO generated in a good working blast furnace to possibly combine with the oxygen of the ore, so some of it must be reduced by solid carbon. Mathesius2 made two important contributions. First, he wrote the direct and indirect reduction equations showing the heats of formation in each case and stressed that the indirect reduction reaction produces heat while direct reduction absorbs heat. Secondly, he substantiated Richards' conclusion that there may be a deficiency of CO gas and that some direct reduction is required, but he pointed out that "direct reduction in the hearth has often been confused with direct reduction in the stack, which more correctly should be termed 'premature combustion'." Then he said that "as this carbon is consumed partly by economical (direct reduction in the hearth) and partly by wasteful reactions in ever varying proportions, it is evident that the relation of this total carbon gasified above the tuyeres to the fuel consumption of a furnace cannot possibly have a direct bearing on the economy of furnace operation. The premature combustion of carbon (CO2+C?2CO) must therefore in all cases be considered a detrimental reaction." Johnson3 discussed this whole problem. Through experience Johnson found that when departure from Gruner's ideal working is considerable, the fuel economy is poor, and when the quantity of blast goes up, the fuel economy goes up in the same proportion. Johnson said that the wind per pound of coke is a measure of fuel economy, which will be shown to be wrong. Howland4 established the fact from operating data that there was no relationship between the coke consumption of a furnace and the percentage of coke burned at the tuyeres. But some of his calculations have led to questionable conclusions, such as "it is practically impossible to obtain low coke consumption unless we keep our wind low." Howland made an important contribution when, in his concluding paragraphs, he reached certain negative decisions as to why one coke works better than another. He said the reason one coke works better than another in a blast furnace is not because: 1—there is any difference in the percentage gasified at the tuyeres, or 2—there is any difference of wind required per pound of coke. Korevaar5 propounded a new theory on combustion which disagrees with Gruner because "as far as we can see, this is sufficient proof for the invalidity of Gruner's ideal, for if it was valid, the Low coke consumption should always be accompanied by a higher percentage of carbon burned at the tuyeres. This not being the case, we must deliberately give up our belief in Gruner's ideal." The part in italics will be proved to be wrong. Martin" contended that there was not enough reducing capacity in the blast furnace unless solution loss occurs. He came to a series of conclusions, such as: 1—The greatest efficiency of the blast furnace may not be attained when the reduction is performed entirely by carbon monoxide as demanded by Gruner's definition of the ideally perfect working of the blast furnace. 2—The so-called solution loss reactions, which should more properly be termed direct reduction reactions, promote furnace efficiency. 3—In modern blast furnace practice, the carbon consumption of the process is determined primarily by the carbon needed for reduction purposes, any thermal deficiency created by the reduction process being balanced in practice by the use of blast heat. From a practical standpoint further discussion of the theory of chemical reactions is of little moment. There is however one phase of the general theory of chemical reactions which is very important and that is the combustion of coke in the blast furnace. The purpose of this paper is to show that the reaction

Jan 1, 1955

Since early July, domestic producer listings in primary aluminum ingot have been at 53¢ per pound. Dealers, however, lowered their August quotes by 1.8¢-2¢ to 47.5¢-48¢ per pound. BITUMINOUS COAL AND LIGNITE -The wildcat strike of UMWA coal miners which began on June 23 in protest of cutbacks in medical benefits appears to have ended. According to the West Virginia Coal Association on September 7, 1977, all mines in West Virginia were back in operation on September 6 and again on September 7. The Kentucky Coal Association reported approximately 2,500 miners were on strike in eastern Kentucky on September 6, but there was full employment on September 7.

Jan 1, 1977

By R. L. Marovelli

ANTICIPATING the eventual use of the huge tonnages of nonmagnetic taconites of the Mesabi range of the United States, the Federal Bureau of Mines is classifying and evaluating these deposits in detail. This introductory report describes work begun in 1954 as part of a long-range program to sample, classify, and evaluate important occurrences of nonmagnetic taconite on the Mesabi, range. Included in this report are brief discussions of the geology, history, and potential of the Mesabi range district and mining industry, together with a more detailed presentation of the sampling and metallurgical evaluation of these nonmagnetic taconite deposits. A total of 898 field samples was collected. Most of these were taken in the region between Grand Rapids and Chisholm, Minn., but a few came from the area between Chisholm and Buhl, Minn. Of the total samples, 865 were from open pit bank faces where the greater vertical distances presented by the cherty members facilitated the taking of a large number of samples. Conversely, the narrow face presented by the slaty members confined and limited the areas from which samples were taken. In addition, 33 of the field samples were taken from rock dumps in order to determine, in a preliminary way, the characteristics of these materials.

Jan 1, 1961