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By John E. Udd

In early 2000, CANMET-MMSL was engaged by the Ontario Ministry of Labour (OMOL) to conduct an international study of the practices, in several key mining jurisdictions, of determining the criteria that are used to decide when the wire ropes used in mine hoisting are to be retired from service. Subsequently, the writer visited key officials and institutions in Canada, the USA, the Republic of South Africa, the United Kingdom, Germany and Poland. Material from the Australian province of New South Wales and Hungary was also included. The report that resulted included, among other sections; (1) the history of wire rope and trends in manufacturing technology; (2) a review of mine hoisting practices; (3) the requirements as regards safety factors; (4) a review of the players and the inspection practices; (5) the criteria for rope replacement; (6) a look into the future to outline the developments that could take place in both hoisting and rope inspection practices in Canada; (7) recommendations. Subsequently, the report was issued as a book by OMOL, and as a CD-ROM by the Mining and Mineral Sciences Laboratories, Natural Resources Canada. In this paper the author presents the key findings and the recommendations made in the study.

May 1, 2003

By Stephen van Duin

As productivity in coal extraction demands increase in underground coal mines, the industry is faced with finding new ways to support production without jeopardising safety. In modern mines the capacity and scale of longwall coal extraction has steadily increased to a point that support processes are failing to keep pace. In particular, roadway development is continually placed on the critical path of activities which maintain mine production, so any inefficiency in this area is quickly exposed. Original equipment manufacturers are under immense pressure to modify their machines to be more interconnected with each other, with machine communication and logistical sharing of space becoming a known requirement. This paper looks at the changing trends in mining practice, analysing available technology as well as currently emerging research into hard automation and discusses the need to integrate machinery and processes in order to see increases in productivity and safety.

Aug 1, 2013

By W. N. Hamilton

"Evaporites abound in the Western Canada sedimentary basin, recurring throughout the stratigraphic column and widely scattered over the basin region. Alberta, situated centrally over the basin, includes many of the evaporites within its borders, but only a few have the right geological conditions to form potential economic deposits of salt or gypsum. These include the Middle Devonian Elk Point Group and related evaporites, Upper Devonian Wabamun Group-Palliser Formation evaporites, and evaporites of the 'Triassic Charlie Lake and Whitehorse formations.Salt deposits underlie almost half of Alberta. The major deposits belong to the Elk Point Group, which includes thick salt units in the Lotsberg, Cold Lake and Prairie Evaporite formations. Another, younger salt deposit in the Wabamun Group has only local distribution. Elk Point salts have a maximum aggregate thickness of 430 m in east-central Alberta. The deposits deepen southwestward across the province, from minimum depths of210 m at Fort McMurray to 1820 m at Edmonton.The thickest, most extensive salt deposits are the upper Lotsberg and Prairie Evaporite salts. Both have excellent development potential. The upper Lotsberg is up to 150 m thick, consists of clear, very coarse crystalline halite with only minor impurities, and has a notable lack of non-salt strata in its succession. Analytical data for the Lotsberg Salt show extraordinary chemical purity. Prairie Evaporite Salt differs lithologically from the Lotsberg in having a significant non-salt component. The deposit is up to 200 m thick and consists of medium crystalline halite, brownish coloured and cloudy as a result of finely dispersed impurities. The main impurities-shale, anhydrite and dolomite-are most prevalent as interbeds in the salt succession, ranging from very thin laminae to beds several metres thick. Although of lesser purity, the Prairie Evaporite Salt is shallower, thicker and more extensive than the Lotsberg and the salt quality is quite acceptable for most industrial uses."

Jan 1, 1982

By R. D. Parker

Location The Frood ore-body is expressed on surface as a prominent gossan ridge, with a total length of approximately two miles. The original Frood (the old No. 3 mine of the Canadian Copper Company) is at the southwest end of this gossan; adjoining it on the northeast is the Frood Extension (until 1929 the property of i:he Mond Nickel Company), while at the extreme northeast end is the Stobie mine. The first two of these divisions of the ridge form the Frood mine as it is known today.? This lies in lots 6 and 7 of the sixth concession, township of McKim, and is two and a half miles north of the city of Sudbury. The general elevation is 1,000 feet above sea level. The Ore-Body The Frood-Stobie parallel offset(l), as its name implies, has no connection in the field with the main mass of the Sudbury nickel eruptive-a norite. It lies one mile to the southeast of that body, and, in general, parallels it in strike. The ore occurs as a more or less tabular structure in what is known locally as the Sudbury series. They are the oldest rocks of the district, and have been placed by Collins(2) as earlier than the lower Huronian, of pre-Cambrian time. The series is comprised of sediments, volcanics (both acid and basic flows), tuffs, agglomerates, breccias, and basic intrusives, all highly metamorphosed, yet all forming a more or less regular picture. The controlling feature of the area has been the attitude of the sedimentary strata, from which has arisen the present sill-like character of the flow rocks, the basic intrusives, and the ore-body itself.

Jan 1, 1932

By V. K. Karra

"A simplistic algorithm jar simulating the rod or ball mill Bond grindability test applied to ores and minerals is presented. A performance comparison between the present algorithm and a previously published algorithm by Kapurot, modified in this work jar a fair evaluation, is also given. A worked example is furnished jar leading the reader through the various calculations.IntroductionThe Bond grindability test is widely used for the prediction of the power requirement of an industrial grinding mill. The procedures for conducting this test in either a ball or a rod mill are available(1). In the case of a ball mill, batch grind abilities have been correlated to Bond grindabilities to help monitor day-today variations in ore grindability for the purpose of plant control( 2,3). Of special interest is the algorithm presented by Kapur(3) for the simulation of the Bond test. In practice, the test lasts from 6 to 14 cycles (4 to 10 hours). With this algorithm, one can predict the Bond grind ability using information available from only the first two cycles.Sometimes the prepared feed for the grindability test contains too much fines compared to the total product desired at the mesh of grind under consideration. In such a case, the operator separates the fines from the test feed and adds to the remaining coarse fraction an equal amount of fresh feed. This combined feed then forms the feed to the first cycle of the test. In the present work, Kapur's algorithm is modified to include this special case. A new and relatively simpler algorithm is also presented. Statistical equations relating work index to pertinent variables are also given."

Jan 1, 1981

?Founded in 1969 by the Ruia family ?Diversified global business corporation with a balanced portfolio of assets in the manufacturing and service sectors; $15 Billion revenue in FY 2009-2010 ?Employs 70,000 people worldwide with offices in Asia, Africa, Europe and North America

May 1, 2011

By Zara Hosseini

?Microseismicity ?Seismic Systems ?Intrinsically Safe and Explosion Proof Seismic System ?Case studies: ?Gas Drainage Optimization ?Fault Identification ?Conclusion Seismic Event ?Occurrences in which energy is released in the rockmass creating a series of seismic waves propagating throughout the rockmass ?Can cause a Fall of Ground or CoalBurst Factors creating Seismicity: ?Mining at Depth ?High stress zones ?Major geological structures ?Mining practices and strategies ?Mining activities i.e. drilling and blasting

Aug 1, 2013

By H. M. Thurgood, F. A. Godfrey, F. W. Gilbert

This is a detailed presentation of the ancillary facilities, including power production, water supply, shiploading facilities, fire-fighting equipment, housing and community services. Additional subjects discussed include construction problems, townsite philosophy and staff organization.

Jan 1, 1968

By M. Abumiya, N. Onodera

Stabilization of arsenic via the precipitation of large-sized scorodite (FeAsO4·2H2O) particles usually involves the use of expensive autoclave systems operated under high temperature and pressure conditions. Alternatively, DOWA developed a novel scorodite synthesis process (DMSP®) wherein the Fe(II) ions in solution containing As(V) ions were oxidized by O2 gas under atmospheric pressure. In this process, crystalline scorodite particles were formed via the formation of a gel-like precursor containing Fe(II). Based on this concept, in this study, we have demonstrated the synthesis of scorodite particles by the addition of Fe(III)-containing solution to the experimental solution containing Fe(II) and As(V) ions, without the O2 gas oxidation process. Ferric sulfate (Fe2(SO4)3) was used as the source of Fe(III) ions. Results indicate the precipitation of scorodite particles, comparable to that of the O2 gas oxidation method.

Jan 1, 2014

By S. Nakamura, M. Takaoka, Y. Mizuno, T. Kusakabe

"Mercury is produced as a byproduct from gold mines and, historically, has been transferred to recyclers and used for various industrial processes and products. However, under the Minamata Convention on Mercury, adopted in 2013,the intentional use of mercury in processes or products will be minimized in the world. Surplus elemental mercury should be treated as a hazardous waste and consequently, should be converted to a more stable chemical form for long-term storage or permanent disposal. A stabilization method has been developed to react mercury and sulfur using a planetary ball mill. The planetary ball mill can produce high-energy conditions and enable samples to react within a short period of time. A series of tests has been conducted to confirm that mercury sulfide can be produced using a bench scale machine with 2400 mL pot. Under a suitable experimental condition with 25 mm ball diameter, 30%of ball filling rate and 1.05 of molar ratio of S/Hg, a powdered mercury sulfide product was successfully obtained in 60 minutes. The leach ability and atmospheric emission from the product was extremely low. This stabilization method would contribute to an environmentally sound mercury management strategy for the gold industry.INTRODUCTIONDue to its unique physical and chemical properties, mercury has numerous applications, including in industry and medicine. However, mercury and its compounds are highly toxic. For example, in Japan, methyl mercury in waste water caused Minamata disease in the 1950s, which affected large numbers of people (Minamata Disease Municipal Museum, 2001). In recent years, environmental pollution caused by emissions and releases of mercury into the atmosphere, waterbody and land by various emission sources such as coal fire plants, artisanal and small-scale gold mining (ASGM), non-ferrous metal industries, waste incinerations etc. has also become a significant problem. To protect human health and the environment from anthropogenic emissions and releases of mercury and its compounds, the Minamata Convention on Mercury was adopted in 2013(UNEP, 2013)Because ground gold ore typically contains mercury at 0 to 100 ppm, mercury is often produced as a byproduct from gold mines (UNEP, 2016). In gold mining operations, mercury can be released from the ore by roasting or by leaching in cyanide solutions and recovery onto activated carbon. According to Yanget al. (2016), 85.1%of mercury in a concentrate was vaporized during a roasting process. Both processes finally discharge elemental mercury as a byproduct. In the USA, more than 100 ton of mercury was discharged from large-scale and industrial gold mining (Miller, 2004)."

Jan 1, 2017

By T. Sugawara, S. Hara, Y. Mitsui

Surfaces of rock slopes in cold regions often become frozen in winter. Therefore, understanding time-dependent behavior of frozen rock, as well as that of unfrozen rock, is important for long-term stability assessment of rock slopes. In this study, a series of uniaxial compression tests and creep tests were carried out on Shikotsu welded tuff under dry and water-saturated conditions at -20 °C to clarify timedependent strength and deformation of the frozen rock. The influence of water content on them also was investigated. It was found that the amount of deformation of the water-saturated specimen was much greater than that of the dry specimen. It also was found that the creep behavior of the water-saturated specimen was similar to that of polycrystalline ice. These show that deformation of the water-saturated specimen is strongly affected by pore ice. The UCS of the water-saturated specimen was approximately equal to that of the dry specimen at a strain rate below 4.2×10-6/s, and its value was about 17 MPa. However, the former increased up to 26 MPa at 4.2×10-4/s with loading rate, whereas there was little increase in the latter. This means that the UCS of the water-saturated specimen was always greater than that of the dry specimen at higher strain rates. The creep life of water-saturated specimens was longer than that of the dry specimens at stress level greater than 15 MPa. These results of UCS and creep life show that inclusion effect due to presence of pore ice plays an important role on strength of the water-saturated specimen. Creep life of the non-failure specimen that was loaded for more than three days was estimated by the relationship between creep life and axial strain rate at 10 s on failure specimens. It was found that creep life of the water-saturated specimens was shorter than that of the dry specimen at stress levels less than 14 MPa. This suggests that estimation of creep life of frozen rock under water-saturated condition is important for the stability assessment of frozen rock slopes. It was clear that the loading-rate dependency of UCS was related to the stress-level dependency of creep life in both dry and wet conditions. This indicates that there are common fracture mechanism in creep and uniaxial compression tests. It also indicates that the creep life can be estimated by the relationship between the UCS and the loading rate. The time dependencies of the water-saturated specimen were in good agreement with those of polycrystalline ice. This confirms that pore ice strongly affects the strength of the water-saturated specimens as, well as the deformation behavior.

Jan 1, 2015

By K. A. Clark

A meeting between representatives of the Scientific and Industrial Research Council of Alberta and the Deputy Minister of Mines for Canada was held at Edmonton in May, 1929, for the purpose of formulating a co-operative plan for carrying forward studies in aid of the development of commercial methods for utilizing the bituminous sands of Alberta. It was agreed that to the Alberta Research Council should be allocated the general problem of investigation of the processes for the separating of bitumen from the sands, including studies of methods of emulsifying, dehydrating and otherwise preparing separated bitumen for industrial applications. It was further agreed that during the present year the work of the Alberta Research Council should be to continue its laboratory investigations of points of design of its separation plant; to further perfect its separation procedure; to recondition its existing separation plant at Dunvegan Yards, Edmonton, in the light of laboratory studies and to operate it for the purpose of demonstrating its efficiency; to carry on tests in emulsifying and dehydrating or otherwise preparing separated bitumen for industrial application; and on the basis of the experience gained in the operation of the preliminary plant at Dunvegan Yards to prepare and design and, as far as possible, to proceed with the erection of, a semi-commercial separation plant at a site to be chosen, probably at the bituminous sand deposits near McMurray, Alberta. This paper presents, in the main, a progress report of the carrying out of this programme.

Jan 1, 1929

By R. Loj

Katowice Coal Holding (KHW) is one of the largest coal companies in Europe. The company owns five coal mines with a daily output of around 60 000 tons of coal. In the Katowice city area, very good quality steam coal is extracted. The depth of mining varies between 400 and 1100 m and some of the mines rank amongst those most afflicted by methane in the Upper Silesian Coal Basin, with the methane hazard having a significant impact on production and safety. ?Myslowice-Wesola? mine, being a part of the Katowice Coal Holding is characterized by high methane and rockburst hazards. The mine is equipped with a modern surface drainage pumping station. At the mentioned mine, longwall 514 was selected for analysis of its methane emission. The longwall was extracting the thick seam 501 (over 4 m), at a depth of over 900 m, which was subject to high stress and high gas concentration conditions. At a distance of about 50 m above, seam 501 is covered by thin seam 416. The strata between these two seams are sandstone and mudstone layers. In the floor of seam 501, with a thin shale interlayer, is located seam 510, which is the thickest (over 10m) and richest coal seam in the Upper Silesian Coal Basin. In longwall 514 and it?s vicinity, methane was the dominant risk. For this longwall three methods of classical gas drainage were carried out. At first, drainage was undertaken using long boreholes from a cross-cut at level 665 m, located far from the production panel. Later, it was performed using typical boreholes drilled from the ventilation gallery (tail gate road). Finally, it was undertaken using a degassing drift executed in the upper coal seam 416. All of these headings, ie. cross-cut level 665 m, the ventilation road and conveyor road in seam 501 and the degassing drift in seam 416, were equipped with media for drilling and proper drainage pipelines. Due to the high rockburst hazard and some problems with caving, several kinds of de-stressing and torpedo blasts were carried out in both coal seams and roof rocks. The subsequent analysis and experiments allowed the establishment of some general rules for carrying out degassing operations effectively. The effectiveness of a degassing drift was demonstrated. In some instances, the system allowed more than 70% of the total methane released to be captured and fed into pipelines. The aforementioned blasts had a marginal impact on methane emissions and the efficiency of degassing methods. Cyclic drilling and regular switching of boreholes in phase with the mining progress and working face advance were shown to be essential.

Aug 1, 2013

By Vard H. Johnson

"In contrast with the well-publicized Pittsburgh coal, and the Everglades of Florida, most coal-forming swamps of Cretaceous time in western North America occupied relatively limited areas. They formed in areas of irregular subsidence, bounded by the changing levee systems of meandering streams. Coke quality is determined by the physical and chemical behaviour of the vitrain during thermal decomposition. Vitrain is at least in part a colloidal substance, originally containing large proportions of water; its formation and survival depend on maintaining a shallow cover of stagnant water up to the time of burial. Heat from swamp fires or subaerial dyhydration could destroy it or impair its quality. Observed patterns suggest that the metamorphism is almost entirely thermal, and that there is little relation to tectonic stresses, or loading. These coals had probably achieved essentially their present rank prior to deformation. Evidence of frictional heating along the thrust planes is minimal or absent. Normally, coal beds are aquifers. Oxygen carried into the subsurface becomes available and reacts with the vitrain to destroy its natural thermoplastic properties. The tolerance of oxygen without loss of thermoplasticity is inversely related to the volatile content. Significant lateral variations of coal thickness are common and sometimes occur in short distances. In deformed areas these thickness changes are more commonly due to differential tectonic stress rather than to original thicknesses of coal. Locally, coal is known to have flowed into cavities, or fractures. These principals are discussed in relation to coal deposits of western Alberta and eastern British Columbia."

Jan 1, 1972

By K. K. Mamyrbayeva, G. Z. Guseinova, V. A. Luganov

This paper presents the results of theoretical and technological studies on leaching ore of Bozshakol deposit. The major oxidized copper mineral of Bozshakol ore is atacamite, and the content of malachite, azurite, cuprite, copper sulfide minerals is insignificant. The chemical composition of the test sample, with mass, %: 0.9 Cu; 55.00 SiO2; 22.40 AI2O3; 9.00 Fe2O3; 2.24 CaO; 3.56 MgO. Technological studies on leaching the ore were carried out with sulfuric acid 5, 15, 25 and 50 g/dm3 in one and multistage (up to 4 stages) countercurrents. Size of ore 1 mm, the ratio S : L 1: 4. It was found that with increasing of acid concentration from 5 to 50 at one-mode leaching the copper extraction reaches 55 %. At multistage leaching the copper recovery reaches 73 %, a productive solution containing g/dm3: Cu - 4; Fe – 1.2; Al – 1.1 at a pH of 2.8. When leaching the cinders obtained by ore roasting in an atmosphere with limited value of oxygen, with increasing of the roasting temperature from 650 up to 750 °? the extraction of copper from the Bozshakol ores reduced from 31.5% down to 24.4%. The rate of filtration is markedly increased compared with the crude ore. When leaching the cinders obtained by roasting in a nitrogen atmosphere a marked increase up to 87.2-88 % of copper extraction from Bozshakol ores is observed. As an extractant for the extraction of copper from the pregnant solution used LIX984N extractant in kerosene. On the basis of the calculations it was built extraction isotherm and modeled processes of copper recovery with the circuit 2E + 1P, allowing up to 93 and 96% extraction. The through extraction of copper from the ore in the electrolyte was 67 %. Technology is recommended for semi test.

Jan 1, 2016

By J. Nalaskowski

A study of the interfacial properties of the basal plane and the edge surfaces of talc is described in this paper. The isoelectric point measured at the two different crystallographic planes by the streaming potential method was found to be similar and exists at about pH 3.0. In the case of the edge surface the zeta potential increases at higher pH values which can be attributed to the hydration of magnesium ions at the edge surface. The atomic force microscopy (AFM) colloidal probe technique was used to measure interaction forces. For such experiments a 20 um talc particle was attached to the AFM cantilever and forces between the edge of the talc particle and two different crystallographic planes of talc were measured at various pH values. These measurements, while being qualitative due to the poorly characterized contact area, show differences between the properties of the base plane and edge of the talc and correspond to the results from streaming potential measurements. Finally, the differences in the hydration of the basal plane and the edge of talc are revealed from molecular dynamics (MD) simulations. The basal plane of the talc is much less hydrated than the edge, as can be seen from the water density distribution functions, which correlate quite well with the contact angle measurements at the basal plane surface and the edge surface of the talc sample.

Jan 1, 2006

By Adam J. Szladow

"INTRODUCTIONThe low calorific value and the high moisture and ash contents of run-of-mine (r.o.rn.) lignite limits the utilization of Saskatchewan lignites to thermal power plants in Saskatchewan, Manitoba and western Ontario. On the other hand, the low sulphur content and the low mining cost make lignites potentially attractive for new coal markets, if suitable processes can be found for upgrading. Economic upgrading to a higher quality fuel would make lignites more acceptable for industrial and utility boilers.This paper presents a summary of the process engineering evaluation of coal upgrading technologies conducted in support of a study of selected lignite upgrading processes. The summary presents the relative advantages and offers specific comments on the application of coal upgrading technologies for lignites. ResourcesLignite comprises the largest fossil fuel energy deposits in Saskatchewan. The total resources of immediate and future interest exceed 27 billion tonnes. The measured and indicated lignite resources of immediate interest are large enough to last for over 200 years at the current production rate of about 10 million tonnes per year (Table 1).Saskatchewan lignitedeposits are present in three different geologic formations: (I) the Ravenscrag Formation of Paleocene Age in southern Saskatchewan; (2) the Swan River Formation of Lower Cretaceous Age in central north Saskatchewan; and (3) the Judith River Formation of Upper Cretaceous Age in central west Saskatchewan. The deposits in the Swan River and Judith River Formation are not currently of economic interest.The Ravenscrag deposits are confmed to four lignite basins, namely: the Estevan, the Willow Bunch, the Wood Mountain and the Cypress basin (Fig. 1). The estimated resources of immediate interest in the four basins are over 7 billion tonnes (Table I). These resources include lignite seams at least 1.5 m thick, at depths of less than 45 m.The average quality of lignite varies relatively little between the four basins considering the distance between deposits (Table 2). There is, however, a progressive increase in moisture and ash content, and a decrease in calorific value and carbon content as one moves westward from the Estevan to Wood Mountain and Cypress basins. The Estevan area deposits are of higher rank despite the fact that they are stratigraphically younger than the Willow Bunch deposits (Cameron and Marconi, 1979).In upgrading lignite to a higher quality fuel, it is important to know not only the average proximate and ultimate analysis (Table 2) but also other lignite characteristics influencing the product quality . For example, Figure 2 shows the effect of lignite HIC ratio on the product equilibrium moisture for hydrothermal treatment of lignite. It is apparent that lignites with a higher HIC ratio, or high liptinite content yield much better quality product for the same hydrotreatment conditions. Other examples of lignite characteristics which are important in upgrading include distribution of sulphur forms and mineral matter, maceral composition and degree of surface oxidation."

Jan 1, 1989

Mine Safety in Chile ?Since the year 2000 fatality rate averages 34 per year ?1% of world mining labour force but 8% of world?s mining fatalities San Jose Mine Safety ?From 1998 to 2010 eight fatalities ?In 2003 mine inspectors recognized no second means of egress and a raise system was developed ?In 2006 182 workers were injured, 56 of them seriously ?In January 2007, there was a fatality after a rock burst, and the government ordered the mine closed ?Less than a year later the mine was back in operations. It had not complied with some of the basic safety measures ordered. One of those measures was to complete the escape way ladder.

May 1, 2011

By W. A. Gow, V. F. Harrison, H. H. Mccreedy

A semi-continuous bench-scale, countercurrent-decantation system, in which the ore was moved countercurrently to the flow of leaching solution, was used to conduct acid-leaching tests on uranium ore with the aid of bacteria. This method, which involved a low degree of agitation, was successfully applied to extract uranium in practical amounts and at practical rates. The acidity of the leaching solution was the main variable investigated in the bench-scale tests done at the Mines Branch, Ottawa. Over 90 11er cent of the uranium was extracted in a six-stage system. The results suggest that this technique could be ap-plied in the utilization of bacterial oxidation and leaching as a method for treating Elliot Lake uranium ore.

Jan 1, 1969

By J. Costigan, C. Corless

In 1997, damage as a result of Castrol R40 entering the INCO pressure carbonyl plant carrier gas stream was becoming increasingly severe. The oil in the gas stream was adversely affecting both equipment availability and process control resulting in rising unit costs. The main source of the Castrol R40 was determined to be the carrier gas and low pressure gas blowers. Plant personnel initiated a plan to prevent the Castrol R40 from entering the carrier gas stream by replacing the mechanical shaft seals with Ferrofluidics seals on these blowers. The following paper details a brief case history of the Castrol R40 in the carrier gas including impact on the plant. This will be followed by a technical discussion of the new sealing arrangement that was developed by plant personnel, Roots Blower and Ferrofluidics. Lastly, this paper will update the status of the blower upgrade project and document the results to date.

Jan 1, 2000