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By Y. S. Sun, Northeastern University, W. B. Li, P. Gao, Z. Y. Zhang, J. W. Yu

"The boron-bearing iron concentrate was extracted from ludwigite ore by the process of magnetic-gravity separation. In order to fully utilize the refractory ore and meet the boron consumption of China, a novel process for separation of boron from iron in boron-bearing iron concentrate was proposed in this paper. In particular, laboratory scale experiments of improving boron reactivity were performed. Fine boron-bearing iron concentrate briquettes were reduced by bituminous coal completely at 1125 °C for 150 min. The effect of sodium carbonate, which was used as an additive in the roasting process, was investigated. The addition of sodium carbonate decreased the boron reactivity and facilitated the volatilization of boron. The influence of diverse cooling methods of the reduced samples on the boron reactivity was studied. The results indicated that boron reactivity could reach up to 80.76% when the reduced samples were cooled by rapid water quenching. In addition, the magnetic material containing 92.71 % Fe with a recovery of 95.11 % and boron-rich non-magnetic material containing 14.51% B2O3 with a recovery 88.85% could be obtained by low-intensity magnetic separation. The magnetic material and boron-rich non-magnetic material were good raw materials for steel-making and borax production, respectively.INTRODUCTION Ludwigite ore is abundant in Liaoning province of China, with 28.43 Mt B2O3 accounting for 57% of the boron resources of the country (Liu et al., 2006). However, it has not yet been utilized on an industrial scale due to its complex mineralogy and fine mineral dissemination (Wang, Wang, Ding, Ma & Xue, 2012). At present, boron-bearing iron concentrate and boron concentrate can be obtained from ludwigite ore using magnetic-gravity separation. The boron concentrate contains B2O3 12%~16%, which can be used as a high-quality raw material for the boron chemical industry after activated roasting, but the B2O3 content in the iron concentrate reaches up to 4%~6%. In order to further separate boron and iron from boron-bearing iron concentrate, a blast furnace and a solid pre-reduction followed by electric arc furnace melting have been proposed (Liu, Cui & Zhang, 1998; Wang et al., 2012). However, both of these two current routes face the same crucial problem that molten boron-rich slag has to be cooled slowly to obtain the alkali-dissolution activity of boron, which affects the yield of boron resource."

Jan 1, 2016

By N. Erarslan, M. Ghamgosar

With the increased use of mechanized rock excavation, there have been developed internationally a number of methods to assess the abrasivity of rock materials. These methods range from determination of abrasive and hard mineral content using petrographic thin section analysis to weight loss or rate of wear flat development on specified test pieces. The Cerchar abrasivity index (CAI) test has been widely accepted for the assessment of rock abrasiveness and is determined as the abrasion of a steel pin after scratching over the freshly-broken or saw-cut surface of a rock. Two types of testing devices are in use today: (i) the original ‘Cerchar apparatus’, and (ii) the ‘West apparatus’, which was adopted herein. The CAI is calculated from the measured diameter of the resulting wear flat on the steel pin after 10mm scratching. This test has been considered to provide a reliable indication of rock abrasiveness for isotropic rocks. However, a great amount of rocks in natureis anisotropic. Phyllite is an anisotropic and foliated metamorphic rock and various types of phyllite specimens were tested in this research. Although phyllite is a type of rock primarily composed of quartz and the expected CAI value can be high, mechanical cutting of this rock should not be very problematic compared with igneous rocks have same CAI value. As phyllite is a foliated metamorphic rock, most of the specimens split into sheets through the quartz seam by the tip during scratching normal to the axis of quartz seams. Hence, viability assessment of Cerchar abrasivity test and F-Schimazek index values for the anisotropic rocks is investigated in this research.

Jan 1, 2015

By T. Patching

"COAL MINING at Canmore, Alberta, began in 1886 and continued there until July 1979. A comprehensive review of the Canmore operations is not available, but the following notes have been prepared to accompany references where more complete information about the operations and problems encountered may be found. The coal measures at Canmore occur in the Kootenay formation of Lower Cretaceous age, and at least twelve seams of varying thickness and horizontal extent have been recognized. The coal, of high quality, ranges from semi-anthracite in the lower seams to low-volatile bituminous in the upper seams. The strata of the Canmore area form an asymmetric syncline, the western limb being overturned to vertical by the Palaeozoic strata of the Mount Rundle Range. The eastern limb is more gently sloping, its dip ranging from IO to about 40 degrees. Tectonic movements have created a troubled and complex coal field. The seams were initially not regularly or uniformly deposited, and mountain-building activity folded and faulted the strata and in many places sheared and crushed the original structures of the coal(l,2,3,4,5). The lack of continuity of the seams, and changes in thickness and inclination, made longrange mine planning difficult and necessitated flexible methods of work, and the local disturbances sometimes created problems in roof support and contributed to the occurrence of sudden outbursts of coal and gas. Almost all of the coal was produced from underground operations but a few relatively small V-cut mines were worked along surface outcrops. These have all been filled in and revegetated. The basic method of underground work was by room-and-pillar, but many variations in layout and sequences were employed. Gangways were driven along the strike and pillars were formed by raises or slopes and crosscuts. Pillars were recovered to the extent that ground conditions permitted by splitting or taking 'skips' from the sides of the raises or splits or crosscuts. Because of the variety of conditions that existed in the field a considerable range of cutting, loading and support methods were employed, including hand-loading, slushers and scrapers, duckbills and shaker conveyors, mobile loaders and continuous miners. Except for the coal obtained by continuous miners most of the coal was broken out by blasting when driving narrow working places or by air picks when cutting from a face. In the early years hand loading onto cars or conveyors predominated. A continuous miner was introduced into Canmore in 1959 on a trial basis, and another was subsequently acquired, in order to minimize blasting and hand loading, but problems in operating these machines in inclining seams and difficulties in providing safe roof support for the machines and workers restricted their efficient use. Another major difficulty with the use of continuous miners was the problem of ventilating development headings in the very gassy conditions. In the early 1970s they were replaced by electric and compressed air slushers and scrapers, resulting in a general increase in productivity, roof control, safety, and flexibility of operations(1.6,7,8.9)."

Jan 1, 1985

By R. W. Allgood

"THE world-wide shortage of elemental sulphur, which became sharply apparent in 1950, has focused attention on the commercial exploitation of sulphur-bearing materials such as pyritic ores, sour natural gas, and smelter gases. Although there •are no known commercial deposits of elemental sulphur in Canada, there are vast quantities of these sulphur-bearing materials. The International Nickel Company of Canada and Canadian Industries Limited have for many years collaborated in an effort to develop economic processes for the recovery of sulphur from the smelter gas arising from Inco's metallurgical operation at Copper Cliff, Ontario. While sulphuric acid has been •produced at Copper Cliff for over twenty years, recent developments will result in a 60 per cent increase in acid production early in 1952 and, later in the year, in commencement of the operation of the largest single unit ever erected for the manufacture of liquid sulphur dioxide.The purpose of this paper is to discuss •briefly the general factors associated with the recovery of sulphur from the Copper Cliff smelter gases and to describe the sulphuric acid operations and the liquid sulphur dioxide development.Processes for the manufacture of elemental sulphur, liquid sulphur dioxide, and sulphuric acid from sulphur-dioxide-bearing smelter gases are well known and in some cases •highly developed."

Jan 1, 1952

By Shin-Kun Ryi

The world nowadays faces many challenges associated with excessive utilization of fossil, fuels, such as poor air quality and greenhouse gas emissions. Hydrogen appears to be an attractive alternative to the conventional, fossil, fuels with better energy efficiency and less environmental, impact. Pd and Pd-based alloy are the most often used membranes for hydrogen separation due to their superiority over other membranes. However, the stability of the commonly-used thin Pd-based composite membranes at high temperatures still, remains a big challenge. In this presentation, we will, report our progress on thin Pd-Ru alloy composite membrane by electroless plating high temperature applications.

Jan 1, 2010

By Warnett Kennedy

"GENUINE CONCERN for the environment is a built-in attitude of mind. If you do not have it by age 40 you probably never will. Some people speak the jargon of 'environment' and 'ecology' for political reasons, others because it feeds their need and bias toward attitudes of moral indignation or dissent. Others pay lip-service for purely business reasons. Complete reactionaries equate conservationists, ecologists and environmentalists as either 'commies' or 'pinkos'. Their real credo is the old saying, ""Where there's muck there's brass."" Those who have genuine concern for good environment are not only romantics like Thoreau but realists who sense the danger to our planet if human greed is rampant and unchallenged. The cities are in real trouble. Almost 75 per cent of the population already live in and around cities. Even mining men live in cities or bring up their children in the new 'instant' towns. The ecology of cities is the concern of all. Our distinguished guest Stewart Udall, in his book ""The-Quiet Crisis,"" quoted Thoreau in 1859 as having written ""each town should have a miniature wilderness park, a primitive forest of five hundred or a thousand acres where a stick should never be cut for fuel, a common possession forever."" Mr. Udall will be glad to know that this advice was taken in at least one instance known to me. I refer to Stanley Park in Vancouver. It is a primitive forest of 1000 acres right inside our small downtown peninsula. It remains unmanicured. This month we celebrated the completion of a seawall of 4%, miles along its perimeter. The construction of this wonderful walkway started in 1910. We are very, very proud of our park."

Jan 1, 1972

By C. Jewell, G. H. Rupay

"67 - 2:15-3:00Regeneration of Hydrochloric Acid from Waste Pickle Liquor Using a Fluidized Bed Reactor System. G. H. RUPAY and C. JEWELL, Dominion Foundries and Steel Ltd., Hamilton, Ont.The disposal of acidic waste liquors from pickling processes has always been a problem for the steel industry. With increased awareness toward environmental control and the problems acidic wastes create, processes utilizing recovery and regeneration of the waste acids are becoming more popular. This paper describes the Keramchemie/Lurgi process for regenerating hydrochloric acid from waste pickle liquor using a fluidized bed reactor system. The process parameters are outlined, together with a brief description of the equipment. This is followed by a discussion of the operating problems and concludes with economic data."

Jan 1, 2000

By D. J. Farmer

Mining hoists are major components of any underground mine, however, the detailed design work required to get the actual power required for a particular hoist is outside the scope of preliminary feasibility studies. Nonetheless, a hoist is costly. Therefore, an accurate estimate is needed for the design parameters and the power required. There are two methods available, namely, the O’Hara method and the Society of Mining Engineers’ method. Tests were done for both methods employing nine friction hoists and 19 drum hoists currently in use at Canadian mines. The O’Hara method provided unacceptable results for both friction and drum hoists. While, the SME method was designed for American regulations and factors of safety which often differ significantly from Canadian ones, good results were obtained. The two relationships deter-mined were simply to add 5% to friction hoist design and to add 4% to drum hoist design. Modifying the SME method by these two factors will allow the hoisting system determined by the SME method to be within the error for a prefeasibility study.

Jan 1, 1997

By M. G. Goudge

IT IS ENOOURAGING indeed to note during the past year that, despite a slackening off in many markets and with numerous major difficulties and problems to solve, the mining industry of Nova Scotia was maintained at a very high level. The value of the Province's mineral production for 1957 amounted to approximately $65,000,000. This represents a drop of only 1.5 per cent from the figure of the previous year. Coal Atlantic Collieries, Ltd., opened a new coal mine during the year at Bras d'Or. This colliery is equipped with the most modern type of mechanical equipment available, with transport of the ?coal by a belt-conveyor system. Other mines in the Province continued to mechanize their operations by the addition of Diesel haulage locomotives and other mechanized mining equipment. New wash plants are in operation and .an additional one is planned.

Jan 1, 1958

By E. R. Olson

The introduction gives not only a historical background but also touches on shaft sinking and surface construction and gives some general information on the Potash Conservation Regulations which the Saskatchewan government introduced in 1969. It also gives information on the corporate and local organization of Alwinsal Potash.

Jan 1, 1972

By S. S. Al-Thyabat, A. M. Ghrair

"Printed circuit board (PCB) is the main part of any electric or electronic device, providing mechanical support and electric connection for the board eclectic components such as capacitors, resistors, diodes etc. PCB consists of non-conductive substrate overlaid with one or more layers of copper sheets. They also contain appreciable amounts of base metals (copper, nickel, tine, and aluminum) and precious metals (gold, silver, and rare earth elements (REE)) which end up in the landfill at the PCB end-of-life.PCB recycling E-waste in general is a profitable business; many valuable raw materials, precious and base metals, can be extracted with high purity. Approximately, one metric tonne of PCBs may contain 80-1500 g of gold and 160–210 kg of copper. The precious metals recovered from PCBs occur at concentrations higher than commercially mined minerals. Also PCB recycling is very important to our environment since many heavy metals (e.g. lead) may be leached from the landfills to the underground reservoirs. In Jordan, however, the work conducted on E-waste and PCB recycling in particular is limited; currently most of the E-waste is either exported or dumped in the landfill.In this work, a combination of physical (magnetic separation), physicochemical (flotation), and chemical methods (leaching) were used to compare metals concentrations in leach liquors produced from a concentrates resulted from a combination of these methods. It was found the leach liquor of the magnetic fraction of the PCB coarse size gave the highest concentration of Fe, Al, and Ni while concentration of Cu was higher in leach liquor of nonmagnetic sink fraction. On the other hand, metals concentration almost similar for both sink and float of the fine size fractions, indicating even distribution of metals concentrations in the fine size fractions."

Jan 1, 2016

By Zhenyu Han, Dion Weatherley, Ruslan Puscasu

"This study aims to demonstrate the capacity of the Discrete Element Method (DEM) to model and simulate fracture in brittle rock, capture the crack propagation process and determine crack propagation rates for various levels of external loading. In the numerical experiments reported here, a macroscopically homogeneous body of brittle rock, containing a single pre-existing crack, was subjected to tensile stress loading. Simulations concerned with model I crack growth process in 3D were carried out. The process of fracture has been observed under various steady state and dynamic conditions. The numerical results obtained reproduce qualitatively and quantitatively a variety of observed fracture phenomena. Specifically, this study examined the onset of cracks, single dominant cracks that grow across the specimen, crack bifurcations and branching. The density of fractures that can be nucleated and grow to a significant size with and without arresting each other, crack growth speed and stress distribution, all have been consistently and systematically analyzed. Suggestions on potential future developments are made and discussed.INTRODUCTIONFracture and failure mechanics are very important in mining, manufacturing, materials processing, mineral processing, civil and mechanical engineering, and many other disciplines of science and engineering. Yet, due to the complexity of fracture phenomena, no theoretical models of broad applicability are currently available (Bieniawski 1967). The simulation of crack propagation is therefore considered an open question in numerical rock mechanics. Although, a significant body of experimental research on fracture of materials was carried out since the early days of fracture mechanics (circa 1940s) (Poncelet 1946, Mott 1948), often in parallel with the development of fracture mechanics theories as well as with the development of experimental and observational techniques themselves, the experimental results were often done on particular classes of material such as glasses and other very brittle materials. Indeed, a number of specific experimental observations on the behavior of growing cracks in brittle materials were made in the 1940s for which generally accepted explanations based on physical principles are still lacking. Likewise, quantitative numerical modeling, based on both continuum and discrete methods, as a basis for understanding dynamic crack growth is still in a preliminary stage."

Jan 1, 2015

By M. Uszko

The paper presents the conditions for determining the selection of methods for methane drainage in Polish hard coal mines. Various factors for the evaluation of methane drainage performance are used, including the methane drainage effectiveness ratio. However, as will be discussed there are limitations to the methane drainage ratio approach resulting from the characteristics of the deposits extracted in Kompania Weglowa S.A. coal mines.

Aug 1, 2013

By Y. Luo

The rock breakage process in drilling is a main source of noise in roof bolting operations, especially when hard rocks are encountered. Proper control of drilling operation can provide an opportunity to improve energy efficiency of drilling and to reduce noise and heat generated from bit-rock friction. Drilling tests have been conducted in laboratory settings to confirm this noise-reduction strategy. Preliminary results show that the drilling parameters, penetration and rotational rates can be controlled to achieve in a desirable range in drilling medium hard rock. Based on the theoretical and experimental studies, rational drilling control strategy is developed for noise control while maintaining a safe and productive roof bolting operation. Applying this strategy in underground roof bolting operation, the noise exposure of roof bolter operators will be significantly reduced.

Aug 1, 2013

By Y. Chunhua, L. Chunsheng, W. Sheng

"Countercurrent solvent extraction is the dominant industrial rare earth separation method. For the rare earth separation, with low separation factors and multiple components, designing and optimization plays an important role in reaching product quality and reducing separation plant costs. Based on the theory of countercurrent extraction, cost-efficient methods, such as third-outlet separation and hyperlinked extraction processing, have been introduced following computer simulation. The consumption and fixed investment of industrial practice are compared, by which advantages of the optimized rare earth separation process are indicated. INTRODUCTIONThe rare earths (RE) have outstanding optical, magnetic and electric properties in advanced material applications and have therefore received much international attention in recent years. Liquid-liquid extraction is the major industrial RE separation method and is widely used in the industry. Supported by the government and with collaboration from the institutions and enterprises, China has made great progress in RE separation, and has become the dominant supplier of separated RE products. Complicated by multiple elements and low separation factors, careful design of RE separation processes is vital for the quality and cost of production. The theory of separation is the key to basic of flowsheet design and industrial applications.BASIC SEPARATION PROCESS AND THEORYGeneral ProcessAcidic extractants such as P507, P204 and naphthenic acid, are the most popular extractants in modern RE separation industry. In the general separating process, the extractant is saponified with a base, then ion-exchanged with RE solutions, thereby to provide stable and high RE loading in the extractant to fulfill the requirement of production quantity and quality. The RE-loaded extractant is then countercurrently extracted and scrubbed with RE solutions and the RE element thereby is purified. After the countercurrent extraction process, the RE-loaded extractant is stripped with acid to obtain an aqueous RE product, and prepare the extractant for recycling (Xu, 1995)."

Jan 1, 2012

By Sunil S. Gandhi

"The Mountain Lake deposit is a tabular sandstone-type uranium deposit, hosted by the basal unit of Middle Proterozoic Dismal Lakes Group. Uranium occurs mainly as sooty pitchblende disseminated in stratiform lenses within gently dipping quartzose sandstone. It is associated with copper sulphides, pyrite, hematite, and traces of nickel and cobalt arsenides and of silver.Exploration HistoryUranium showings on the PEC claim group were discovered during 1969 by an airborne radiometric survey carried out over the Dismal Lakes-Great Bear Lake area by Aquitaine of Canada Limited (Bizard and Salat, 1969). Some drilling was done in the vicinity of the showings in 1975 by the company under a joint venture with Eldorado Nuclear Limited but the results were not encouraging (Hassard and Woollett, 1975). During 1972, Trigg, Woollett and Associates Limited conducting surveys for Imperial Oil Limited, discovered numerous high-grade radioactive boulders scattered over a distance of several kilometres north and west of the showings, and the area north of the PEC claims was staked as the YUK claims (Ahuja, 1974). A systematic study of the boulder distribution and Pleistocene geology suggested a source additional to the showings. More intensive exploration followed, and in 1976 drilling just north of the PEC claim group boundary intersected the main deposit at a depth of 75 m to 150 m, beneath overburden up to 60 m thick. Part of the deposit extends into the PEC claim group which is under exploration by the Aquitaine-Cominco Joint Venture.The following brief description is based on the presentations in 1978 by F. Hassard of Trigg, Woollett and Associates Limited at the Geoscience Forum in Yellowknife, and by S.S. Gandhi of the Geological Survey of Canada at the Mineralogical Association of Canada Uranium Short Course in Toronto."

Jan 1, 1986

By C. Dupuis, P. Waite, S. Leboeuf

Casthouses throughout the aluminium industry commonly use chlorine gas as a fluxing agent for furnace and in-line treatment of molten aluminium alloys. Its positive impact on the removal of alkali elements and non-metallic inclusions is well known. Nevertheless, the elimination of its use is highly desirable due to the safety and environmental risks associated with storage and handling. Over the past decade, the aluminium industry has significantly reduced its chlorine consumption. This has been achieved by maximizing the chlorine gas utilization efficiency during metal processing, and by the chlorine replacement for crucible and furnace metal treatment applications. Operation of sealed in-line treatment units without chlorine is now possible, but with lower or inconsistent removal efficiency penalties for alkali and inclusions respectively. This paper reviews the progress made at Arvida Research and Development Centre regarding the reduction of chlorine and the development of an alternative to chlorine for in-line metal treatment without penalizing the metallurgical performance.

Jan 1, 2006

By J. M. B. Scarborough

This paper deals with measures taken to maintain effective operation of heavy-duty equipment in open-pit mining. at Pine Point, N.W.T., during periods of extreme cold weather. The points covered include equipment modifications designed to improve cold-weather performance, effective lubrication of machinery that is vulnerable to extreme cold and operating procedures designed to prevent equipment damage.

Jan 1, 1966

By J. E. Gill

"The Wasa Lake property is a block of about 1,640 acres in Beauchastel township, Quebec. Gold was discovered there first in 1936 in what is now known as the 'Southern area ( Fig. 1). Stripping and trenching were followed by 9,218 feet of diamond drilling in twenty holes. A number of good intersections were obtained, but their interpretation in terms of ore was difficult. A shaft was then sunk to 220 feet vertical depth. Thirteen hundred feet of lateral work and 543 feet of diamond drilling were completed at the 200-foot level before work was discontinued in 1938. Results up to this point had been just fair.Early in 1944, surface diamond drilling was resumed. The first hole cut material of ore grade in a strong shear zone 1,000 feet north of the old workings, and holes to the east and west showed this to be an extensive gold-bearing zone.In August 1945, a main working shaft was started. This has been sunk to 550 feet slope depth. A cross-cut at 390 feet vertical depth was driven to the ore zone and, by drifting and drilling at regular intervals, a length of 725 feet had been tested to December 31st, 1946 ( Figs. 1 and 2). The results check those from surface drilling quite closely.In the main zone, scoping widths from 8 to 40 feet and averaging about 25 feet are indicated. The grade after dilution should be about 0.15 oz. gold a ton and operation will probably start at 1,000 tons a day."

Jan 1, 1954

By W. Fergusson

This paper takes a look at the use of rubber to provide corrosion resistance and wear resistance in the mining industry. The longer life and reduced down time involved with the use of rubber are stressed, and examples are given of applications in grinding mills, skips, discharge chutes and screens.

Jan 1, 1979