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By E. P. Williams

"Prince Edward Island, Canada's smallest Maritime Province, is located in the southwestern part of the Gulf of St. Lawrence. The Province is more or less centrally located in the Maritimes Basin, a large intermontane basin within the Appalachian orogenic belt. The Maritimes Basin is subdivided into sub-basins and uplifts which exhibit two dominant structural trends: east and northeast. The Basin is known to be petroliferous because of the seeps, shows, oil shales and albertite found in southern New Brunswick and northern Nova Scotia and the gas and oil produced from the Stony Creek field near Moncton, New Brunswick.Permian beds are exposed on the Island, mostly along sea-cliffs. A maximum thickness of about 5,000 feet of red beds -shales, sandstones and conglomerates -make up the sequence. Over most of the Island, the Permian section is much thinner. Four key wells (Mississippian tests) and several shallower tests have been drilled. The Pennsylvanian-Mississippian section thickens rapidly off the Port Hill Uplift at the northwest, where it is less than 4,600 feet thick, and continues to thicken to about 20,000 feet in the Cumberland Basin at the southeast. Geological and geophysical data combine to give us the structural picture of the deeper beds.Prospective reservoir rocks are primarily in the Missis-sippian Horton and Windsor groups. Prospects are:-1. on or over structural highs in the basement; 2. on anticlines or fault highs; 3. over or peripheral to salt domes or salt-core anticlines; 4. at truncation pinchouts of Mississippian prospective beds; 5. in basal sandstone or granite wash on the pre-Carboni-ferous basement; and 6. in facies traps at changes from sandstone to shale or porous to tight carbonate rocks."

Jan 1, 1967

By M. O. Makwarela, M. W. Erwee, K. Bisaka

"Energy efficiency in mining and minerals processing forms part of Mintek’s long-term research strategy which includes a specific programme designed at overcoming the challenges faced by the South African pyrometallurgy industry.The electric smelting industry is currently severely constrained by the global economic downturn as well as by the availability and increasing cost of electricity. Efficient utilisation of electricity through energy recovery systems and improved smelting process flowsheets can significantly contribute towards creating sustainable operations.Apart from efficient engineering design and solid process control, smelting of either cold or hot pre-reduced ores has been shown to decrease furnace electricity consumption by more than 40%. Various methods of solid-state reduction tests have been carried out at Mintek in order to select the most appropriate process option in the context of the South African industry. This paper summarises a subset of the results obtained, specifically on pre-reduction tests done on South African chromite and manganese ore pellets.In this set of tests, it was found that the use of an organic binder, together with B2O3 as flux, promotes manganese ore pre-reduction, but retards the pre-reduction of chromite. By pre-reducing the manganese ore feed, significant cost savings can be achieved in subsequent smelting processes and there is potential to minimise manganese losses as a result of fuming, due to possible lower operating temperatures."

Jan 1, 2016

By Jason J. Ballentine

This case study presents the results of a maintenance review of a soot blower system at a coal fired power generation station. The power generation station was following a ?repair when it breaks? maintenance strategy for its soot blowers. The efficiency losses incurred as a result of failures in the soot blower system and the resulting interruption and out of service time was found to have a significant effect on the plant output. The maintenance strategy for the soot blowers was reviewed using Reliability Cantered Maintenance and lifecycle simulation. This methodology provided visibility to the monetary implications of failures and allowed alternative types of maintenance to be assessed and where justified were added to a maintenance schedule in the Maximo work order management system. By reducing unplanned breakdowns the predicted reduction in efficiency losses was 45%.

May 1, 2007

By Staff

This paper contains an outline of the history of the Sullivan mine, now owned and operated by the Consolidated Mining & Smelting Company of Canada, Ltd.; some account of the various methods by which the ore has been treated in efforts to solve the metallurgical problems which its complex character presents, and, finally, to give, as concisely as possible, an outline of the present mining and metallurgical practice along with a description of the mining and milling plant at Kimberley and the smelter and refineries at Trail, in British Columbia. EARLY HISTORY In May, 1892, Pat Sullivan, John Cleaver and Mike Holland left the Coeur d'Alene country, in the State of Idaho, to seek their fortunes in the Kootenay lake district in British Columbia. They were aided in their venture by James Cronin, afterwards locator and owner of the St. Eugene mine at Moyie. Two months later the party broke up, Sullivan and Cleaver crossing the mountains from Crawford bay on Kootenay lake to the head waters of the St. Mary's river, the course of which they followed down to Fort Steele. Here they found a good deal of excitement about the North Star mine, and, joined by "Ed." Smith, who was familiar with this part of the country, they determined to return and prospect in its vicinity.

Jan 1, 1924

By M. F. Almeida

"Due to the randomness of all factors influencing the sintering operation, a two-stepped procedure is proposed to find the best way of using stocked fines at a plant producing Fe-Mn alloys for the steelmaking industry. The approach is based on the following: (1) predict the result of the sintering operation by establishing the best multilinear regression model using some of the characteristics of the loaded material; and (2) find the best solution under a minimizing cost criteria by solving a linear optimization problem using the regression equation plus constraints on the feed and product. IntroductionSome tests carried out using 20% to 30% of sinter in the material loaded into a 60 000 KVA Tysland-Hole electric furnace producing Fe-Mn alloys for the steelmaking industry indicated: (1) a meaningful decrease in the off-gas temperature and, consequently, a better energy use due to the material higher porosity; (2) more uniform heat distribution as a consequence of the electrode reaction zone enlargement; (3) an improved furnace control resulting in a smoother operation; and (4) a decrease in gas production facilitating the off-gas treatment. For some years, this plant used only the coarse fraction of the Mn ores, thus stocking all the received and own-generated fine particles. In view of the mentioned results, a strategy for increasing the use of stocked fines was formulated, including a step where it was necessary to decide which components and respective quantities should be used in the blends to be sintered (Almeida, 1984).It is well known that several factors affect productivity and energy consumption in sinter production, also influencing the product quality. Raw materials characteristics, namely chemical and size composition, affect permeability to gases and may or may not allow a deeper bed. In general, finer ores decrease permeability, increasing electricity consumption by fans, but due to their higher specific surface area, react more completely with other components in the mixture. For coke granulometry, a compromise must be obtained in order not to burn it too quickly nor to widen the flame front, therefore decreasing productivity. Decreasing coke in the blend also acts in sinter bonding, decreasing its consistency and increasing crushing and return fines. Moisture addition also influences components mixing, pre-agglomeration, bed permeability and, consequently, sintering productivity. Therefore, optimum conditions must be established for both a given sintering plant and the components in the feed (Dawson, 1993)."

Jan 1, 1998

By R. M. Graves, C. B. McKenzie, D. Barbour, D. W. Desnoyers

"Abstract -The prospective Tulks volcanic belt hosts five significant massive sulfide deposits, Tulks Prospect, Tulks East, Jack's Pond, Daniel's Pond and Victoria Mine, as well as numerous showings and indications throughout its 70 km outcrop length. Regionally, the 498 Ma sequence consists dominantly of felsic pyroclastic rocks and flows with interbedded mafic volcanic units and fine­ grained sediments, commonly graphitic. Contemporaneous granitoid rocks occur in the south half of the belt. Rocks usually display a strong NE-SW, steeply dipping, penetrative foliation and other shear-related high-strain fabrics. Facing directions are normally northwest, although there is local evidence of folding. Sulfide bodies and their alteration systems are deformed and shape-modified in the style of ambient strain.The Tulks, Tulks East and Jack's Pond prospects appear to occupy a similar stratigraphic level, on or near the contact between a thick felsic pile and an overlying broad, conductive package of graphitic sedimentary rocks. AU are pyritic deposits with well-developed footwall alteration systems. The Tulks prospect comprises four polymetallic lenses totalling 750 000 t. Three lenses constituting more than 6 000 000 t of sulfide mineralization are indicated at Tulks East but only the 210 000 t ""B"" lens contains significant base metals. Jack's Pond consists of a very extensive, zoned alteration complex in which four lenses of massive to semi-rnassive pyrite + chalcopyrite are known.The central part of the system, characterized by Mg chlorite and carbonate, is enveloped by pervasive sericitization and capped by intensely silicified and pyritized volcanics. The sulfide lenses are interpreted as part of the footwall zone and are beneath that part of the system most likely to host polymetallic massive sulfides.Daniel's Pond differs from the other prospects in such fundamental ways as metal content, associated alteration and structural setting. The deposit comprises strongly tectonized, Ag-rich, Zn-Pb mineralization distinguished by a pronounced Ba-As-Sb signature. Mineralization is confined to a narrow, north-south high-strain zone which separates unstrained mafic volcanic rocks to the east from well-foliated felsic rocks. The deposit Jacks an extensive alteration halo and at its north end is associated with a lens of barren, undeformed massive pyrite.The Victoria Mine deposit, the most cupriferous of the five, is related to a moderately dipping structure that separates well-foliated Tulks volcanic rocks from an overlying, Jess deformed volcanic­ sedimentary sequence that may be as young as 462 Ma. The structure is also the locus of black chlorite, dolomite and quartz alteration. Structurally remobilized precursor sulfide mineralization is one possible source for the deposit."

Jan 1, 1993

By Tuomas van der Meer, Jukka Tanninen, Annukka E. Mäkinen, Mika Martikainen, Laura M. Nevatalo

The mining industry consumes huge water volumes and the waste streams typically contain sulfate, which has caused problems to many operations around the world. Discharge of sulfate to fresh waters is being restricted as the sulfate load increases salinity and causes problems when sulfate is reduced to toxic H2S by natural bacteria. To reduce fresh water consumption, internal water recycling had become a necessity in metallurgical processes. However, the recycling causes accumulation of sulfate and other components in water, causing problems to process performance and increases scaling in piping and equipment. Few technically feasible water treatment processes exist in the market that can be applied to decrease sulfate concentration below gypsum saturation level: biological sulfate reduction, membrane separation, ion exchange, evaporation and chemical precipitation. Some of these technologies are effective for treating wastewater, but there is typically a highly concentrated sulfate fraction left requiring still further treatment. Outotec has developed a sulfate removal solution, Outotec Ettringite process, which allows flexible control of residual sulfate concentration, thereby opening doors for increased water recycle within processes and control of the sulfate in discharged waters. In this article the results and benefits of this novel process along with examples of operating costs are presented.

Jan 1, 2014

By William B. Hetherington

Communities are the foundation upon which the whole structure of society rests and upon which the nation builds its hope for the future. They are not established to serve any one particular generation, nor any one element or group, but should be erected to render a lasting service to all who are to follow. They play a very vital and important role in the lives and welfare of the people, in their industrial, business, and social relations, and in the economy of the nation, of which they are the fundamental assets. Communities and civic governments are destined to be vital factors in the national welfare in the days that are to come. Any improvement in national or world conditions must have its origin within the communities. Any attempt at solution of the community problem must give some consideration to the fundamental elements which exist in every community, and to the underlying principles, and ways of life and thought, upon which community life is based. The community is, in its essence, a number of people living and working more or less closely together, sharing common rights, privileges, conveniences, and comforts, which would be impossible for the individual to obtain for himself by his own efforts alone, or in any other way than by the mutual exchange of persona! services and resources. In this way, men have increased the returns from their labour and commerce, have raised the standard of their living, with better social, educational, and recreational facilities, and enjoy a greater personal security.

Jan 1, 1943

"Mining with blast holes drilled upwards may be done to recover sill pillars, or for economic reasons when the distance between the levels is relatively large. If the rock is sufficiently competent to accommodate large stope size, the distance between sublevels could be increased to as much as drilling accuracy allows. The same drill drift can be used for the drilling of both down holes and up holes. In the case of down holes, the initial opening of the stope (drop raise) is not as much a problem as for the inverse drop raise for mining with up holes. This is because, with a drop raise, a lot of space is available at the toe for the blasted rock to expand. In addition, the raise can be blasted in many shots, thus allowing smaller blasts each time. Inverse drop raises are generally much more difficult to blast because of the limited space for muck flow, and must, therefore, be taken down in a single blast, requiring special considerations in order to ensure a success. A case study of a 29 m (95 ft) inverse drop raise successfully blasted in a single shot at Heath Steele Mines is described. The paper covers technical considerations such as drilling accuracy, hole deviation survey, delay extension and protection, initiation methods and initiation sequence. Finally, a novel method for creating the initial opening called ’slot drilling’ is presented. This method, inspired from LKAB in Sweden, consists of drilling a row of interconnected holes using a special guide mounted on a regular production drill hammer.With a case study of blasting an inverse drop raise of 29 m (95 ft) in one blast, this paper further discusses some technical issues that are critical for the development of inverse drop raises. A novel method for creating the initial opening with a slot of interconnected holes is also presented with the experience acquired at different mine sites across the Noranda group."

Jan 1, 2000

By Euler De Souza, J. Daniel Stinnette, Julian Varaschin

"This paper outlines some of the factors that affect the airflow required for the ventilation of modern diesel-powered equipment and of electric equipment and examines how they can be applied in determining reasonable ventilation rates for Tier IV compliant diesel equipment and for electric equipment operating in mining environments. Airflow calculations for modern diesel-powered equipment and for electric equipment are more complex and must be based on a combination of factors that are unique to each mine. Methodologies for ventilation rate determinations for each case are proposed in this paper.INTRODUCTIONTraditionally, airflow requirements for production and support equipment operating in underground mines have been determined by multiplying the vehicle power by a ventilation rate that was either mandated by regulations or determined empirically from known quantities. However, in light of the drastic reductions to diesel equipment emissions mandated by the US EPA Tier IV and EURO Stage 4 regulations, there is still a great deal of uncertainty in the underground mining industry among those responsible for the ventilation of planned new mines or the expansion of current mines. The question remains, what ventilation rates should the ventilation system designer apply for modern diesel equipment?Also, given the ongoing development of grid/battery-electric equipment and active construction of fully electric mines, it has become critical to determine adequate airflow rates per brake kilowatt of electric engine power. One of the most important criteria for determining ventilation rates for electric equipment is the amount of heat they generate, as this is the most significant emission produced by electric equipment (which do not produce exhaust gases or particulates). Therefore, ventilation rates required to dissipate heat from electric equipment must be suitably determined for all electric vehicle fleets operating in underground mines."

Jan 1, 2019

By K. D. Hester

This paper will review the metallurgical aspects of the completed expansion program at Quirke, and the current rehabilitation and refurbishing program at Panel. During the Quirke program, completed at the end of 1977, the plant capacity was increased from a nominal 4,500 to 7,000 short tons per milling day. The expansion of crushing, grinding, neutral thickening and filtering, leaching, partial neutralization, sand-slime separation, sand washing, C.C.D., clarification, ion exchange, mine water treatment, and tailings neutralization and pumping will be considered. The application of Enviro-Clear thickeners in the mine water treatment circuit and in the C.C.D. will be briefly reviewed. An automatic grinding and classification circuit for limestone will also be covered. The refurbishing program underway at Panel will be discussed. The Quirke and Panel plants will be contrasted and compared. In particular, reference will be made to environmental considerations. The innovative system for producing yellow cake at Panel, LAMIX, will be considered as well as the proposed treatment system for Panel tailings.

Jan 1, 1979

By H. J. McQueen

Mineral and energy resource consumption were continuously reduced by process improvements as chemical understanding was developed and applied. During the past two centuries, technological improvements increased human productivity that was accompanied by social advances and labour saving products; however, these sometimes proliferated to endanger sustainability, e.g., automobiles. In the steel industry, precisely controlled rolling of HSLA steels required little extra mineral consumption but reduced weight and heat-treating energy. Continuous casting of slabs reduced scrap compared to ingots and energy for the homogenizing soaking pit. Al alloy extrusions were improved by retaining the strengthening in the near-surface substructure, of high strength textures and of press quenching that is suitable for direct age hardening. Continuous bar casting of Al-0.65Fe, coupled with rod rolling and followed by wire drawing with only a final recovery anneal, yielded electrical wiring for households to replace less plentiful Cu and later for light-weighting use in autos and aircraft Looking backwards, the 1970 decade saw the first oil crisis and inspired Ottawa to undertake a campaign to develop an energy strategy that would decrease dependence on imported fuels. One significant undertaking under Energy Mines and Resources was the organization of industrial energy conservation, managed by each industry association,that collected detailed current statistics and set the goals for a 2-year campaign. The metal producing industries, as compared by E.C.N. Perryman to about 7.2 exajoules (EJ) for the nation, consumed about 0.8 EJ, being about one third of all heavy industries. While manufacturing consumed 30.2% of total energy, it created 87.3% of total national dollar value. Within the industrial envelope, smelting and refining utilized 28% (0.67 EJ, mining beneficiation 6.7%, 0.16 EJ); there was a significant contribution to exports: 80% of iron ore and 70% of aluminium in 1973. A general concern was that decreases in ore grade would lead to a rise in energy expenditures countering benefits from processing efficiency.

Jan 1, 2012

By M. Vallée

Several reviews of mineral project performance in the past 35 years indicate a pattern of occasional, but recurrent, mining project failures due to shortcomings in geological information and estimation, mineral processing and metallurgical testing, feasibility study objectives and requirements, and project start-up methods. A commitment to quality assurance and continuous improvement methods and to obtaining “ENOUGH DATA, OF APPROPRIATE QUALITY” is essential. Recent international and Canadian proposals for mineral resource and ore reserve definitions have taken a nonprescriptive stance that will undermine the formulation of requirements, guidelines and industry standards for efficient deposit delineation and estimation, and for the determination of project feasibility. To help reduce problems, every feasibility study supporting a mine development and production decision should be based on objectives and methods adequate to reach completion targets similar to the bankers’, as a good business target for a profitable project. In a resource/reserve system, the use of reserve should be restricted to a project that meets required technical, economic and legal feasibility requirements for successful project implementation, and the definitions of these categories should provide explicit limits. Current shortcomings will limit the ability of the Qualified Person to provide “adequate professional practice,” fulfill his/her professional responsibilities to his employer or client and provide adequate information to the investing public. We must take advantage of present opportunities for Setting New Standards for the new Millennium.

Jan 1, 2000

By Jonathan Ruiz Lizardo, Met-Chem Canada Inc., Flavio Ccuno, Constante Umipig, Ewald Pengel, José Ruiz

"Cerro de Maimón is located in the Dominican Republic on the island of Hispaniola approximately 75 kilometers northwest of the capital city, Santo Domingo. The processing facility consisted of two separate processing plants for oxide and sulphide ores. The oxide plant processed oxide ore bearing gold and silver ore using cyanide leaching and Merrill Crowe processes, while the sulphide plant produced a copper concentrate using conventional flotation. Cormidom is a commendatory example how mineral processing facilities can co-exist in balance with the environment. In 2014, natural occurring copper oxide contamination with finer grained copper-zinc sulphide mineralisation was expected to dominate the sulphide ore body. In anticipation Cormidom contacted the original plant designer Met-Chem to assist in overcoming this challenge. Test work indicated that increased flotation time and subsequent very fine grinding were required. Met-Chem provided the detailed engineering and Cormidom proceeded with the expansion project internally. Currently Cormidom has processed the sulphide ore successfully by implementing flotation modifications. This paper describes the history of Cormidom, test work on the “new” ore body, modification in process design in the Cu-Zn sulphide flotation circuit, construction and implementation.INTRODUCTIONCorporación Minera Dominicana (CORMIDOM) was a wholly owned subsidiary of GlobeStar Mining Corporation (a Canadian based minerals exploration company) with extensive exploration of base and precious metals in the Dominican Republic. In 2007-2008 CORMIDOM constructed the Cerro de Maimom project. The company was subsequently sold and purchased by Perilya Limited from Australia in 2013. Cerro de Maimón is located in the Dominican Republic on the island of Hispaniola approximately 75 kilometers northwest of the capital city, Santo Domingo. It is near the town of Maimón in Monsenor, Nouel Province (see Figure 1)."

Jan 1, 2016

By P. Talonen

Since the last Iron Control in Hydrometallurgy Symposium in Montreal in 1996, the Kokkola zinc plant has increased its capacity from 175,000 t/y to 280,000 t/y by installing an atmospheric concentrate leaching process, which has also affected iron control in the leaching circuit. Major changes have been made at the jarosite residue pond; a subterranean plastic wall reinforced with bentonite and cement has been built around the pond. A new water collecting system that is used for groundwater level control in the pond area was installed. With these two investments in the pond area, it is now possible to prevent any seepage flow from the pond into the surrounding environment. Water pumped from the residue pond is treated in the water treatment plant. This paper describes the behavior of iron in Kokkola's current leaching processes. The treatment of the jarosite, the improvements to the residue pond and the water treatment process are also described.

Jan 1, 2006

By R. P. Nicholson

On September 3rd, 1947, the Acadia Coal Company put into operation a central coal preparation plant. This plant was designed to process all coals mined by this Company in the Pictou County coal field. The problem, briefly, was to make a three-way separation of the raw coal fed into the plant. It was desired to remove all stone, metal, and wood from the marketable coal and to produce a splint coal from the raw material which would be suitable for making power. This splint coal product is belted directly to the power plant which is adjacent to the wash plant. To attain this object it was therefore necessary, first, to wash the raw coal, removing all splint, stone, metal, and wood. The stone, metal, wood, and highest-ash splint had then to be removed by a second washing in order to obtain the lower-ash splint for use in the power plant. The plant is on the east side of the Allan colliery, in the town of Stellarton (see accompanying photograph). It is of steel frame construction with wood siding, covered on the exterior with corrugated galvanized iron. Considerable concrete had to be poured for the foundation piers as the plant site is largely 'fill' ground. This necessitated the construction of extremely heavy footings containing a large amount of reinforcing steel. In all, 884 cu. yds. of concrete were poured for the various pits, tanks, and foundations; its average test was about 3,500 lb. per square inch. At the time the plant was constructed, the steel shortage in Canada and the United States was acute and, in order to obtain steel for the structure which is four stories high- an unused part of the Allan bankhead was torn down. Enough steel was obtained from this demolition to fabricate the new plant.

Jan 1, 1948

By K. M. Wild, C. D. Martin, F. Amann

"Argillaceous rock formations, in particular clay shales, are notorious for creating challenges in rock engineering. Due to their generally low hydraulic conductivity and their complete saturation in their natural state at depth, the behavior of clay shales is usually characterized by a strong hydro-mechanical coupling.This paper presents typical pore pressure responses monitored in different underground rock laboratories and explores alternative ways for their interpretation. The underpinning processes and their relevance are identified based on analytical and conceptual numerical models. Pore pressure monitoring data from Opalinus clay at the Mont Terri Underground laboratory, the Boom Clay at the Mol facility and the Callovo-Oxfordian clay in the Meuse/Haute–Marne URL show a similar pore-pressure response associated with stress changes accompanying tunnel construction although the tunnels were built in different rock types, at different locations, and under different in-situ conditions.The numerical analyses in this study shows that the pore pressure response around an excavation in low permeable clay shales may have different explanations. Pore pressure drops observed in the tunnel near field can theoretically be explained by both, a pure elastic response in an isotropic or anisotropic rock mass with an anisotropic stress state, or a inelastic response and related dilatancy. However, a comparison between the numerical models and the in-situ measurements revealed that the latter is more likely. This conclusion is justified by the observation that pore pressure drops occur significantly ahead of the tunnel face which is not the case in elastic numerical simulations. Pore pressure measurements in the far field, where failure processes are unlikely to occur, can only partly be explained by a linear poroelastic models. The introduction of an anisotropic material plays a key role in reproducing the responses, conceptually."

Jan 1, 2015

By Ali Montaser

Hauling trucks are important part of equipment fleets for large earthmoving operations such as those encountered in dams and highway construction projects. This paper presents an automated methodology for tracking and estimating productivity of hauling trucks fleet operations in near-real-time. Recent advancement in automated site data acquisition technologies made their use in tracking and monitoring of construction operations feasible. However, these technologies fail to track hauling truck fleets due to the change in the cut and fill locations from one cycle to another; making tracking and progress reporting difficult and inaccurate. In addition, there is very little work done utilizing data sensed directly from equipment, for example sensing when truck dumping bed is raised during the dumping process. The technologies deployed in the developed method are Radio Frequency Identification (RFID) and equipment control sensors. Low cost passive RFID tags are attached to hauling trucks and fixed RFID readers are attached to loaders or excavators. The read range of the used RFID tag is centimeters, to be activated only when a loader with an attached RFID reader is loading a truck. On the other hand, control sensor is connected to the truck control system and operated by the motion of its movable bed. The function of control sensors is to record the signal time when the truck operator gives order to the truck control system to raise or lower truck bed. The captured data is then transferred wirelessly from the RFID reader and control sensor to a computer housed in one of the temporary offices onsite and subsequently to the main server in the contractor?s head office. Fusing the data captured from RFID reader and control sensor is used to identify loading, travel, dumping and return time that constitute the hauling truck cycle time. The collected data is analyzed and processed automatically, without human intervention, to calculate the productivity of the hauling truck and to report it directly to onsite personnel. Relational database is developed to support the implementation of the proposed method. The developed database is used to process the data captured by the RFID and the control sensor to calculate the productivity achieved in cutfill operations in near-real-time. The developed methodology is expected to facilitate early detection of discrepancies between actual and planned performances.

Aug 1, 2013

By A. Lloyd, Montgomery, J. Jorgesen, W. J.

"Coals are ranked according to their degree of metamorphism or progressive change in the natural series from lignite to anthracite. The reader is referred to ASTM Standard D-388, ""Standard Classification of Coals by Rank"" for a detailed description of the system in use throughout North America including Canada.Fixed carbon and calorific value (expressed in Btu/ lb) calculated to the mineral-matter-free basis have been chosen as the main characteristics from which rank is established. Higher rank coals are classified according to fixed carbon content, lower rank coals according to the calorific value on a ""moist"" mineral-matter-free basis. Certain adjacent groups are differentiated according to their agglomerating (caking) properties. ""Moist"" refers to inherent moisture. Referring to Table 1, coals having calorific values greater than 14,000 Btu/lb on a moist mineral-matter-free basis and fixed carbon of 69% or more on a dry mineral-matter-free basis are classified according to fixed carbon. Coals having calorific values of less than 14,000 Btu/lb on a moist mineralmatter-free basis are classified according to calorific value on a moist mineral-matter-free basis. Agglomerating coals having 69 to 86% fixed carbon on the dry mineral-matter-free basis are classified in the low or medium volatile group of the bituminous class according to their volatile matter content. Agglomerating coals having calorific values between 10,500 and 11,500 Btu/lb are classified in the high volatile C bituminous coal group; nonagglomerating coals in the same calorific value range are classified in the sub-bituminous A coal group."

Jan 1, 1985

By E. H. Henderson

Introduction Stamp-Milling and amalgamation is, perhaps, one of the oldest processes of recovering gold from its ores. Many papers, theses, and textbooks have been written on the subject of stamp-milling practice in general, but, to my knowledge, there have been no publications describing the modern stamp-mill as designed, developed, and operated in Nova Scotia. Although it may be said that the gravity stamp-mill is the most primitive, and perhaps the crudest, crushing machine in existence, it is at the same time the most satisfactory all-round milling and amalgamating device yet contrived. Originating in Saxony, and used in North America first in Virginia and Georgia, the stamp-mill, in a primitive form, later found its way to California and Colorado. Here, it speedily developed from an affair of wood shod with iron, and operated with the crudest gearing, to substantially its present form. Briefly, it consists (see Figure 1) essentially of a series of hammers (the stamps), which fall upon a mixture of ore and water contained in a cast-iron box (the mortar). The resulting crushed ore (the pulp) is splashed out through a screen on the front of the box. For some years after the discovery of gold in Nova Scotia, in 1861, the ? arrastra and Chilean mill were used to recover the gold from the rich ores. The stamp-mill followed, and various types were used, principally the California and Gilpin County types. Then, in 1895, Mr. M. R. O'Shaughnessy, one of our foremost amalgamators, conceived the idea of a new type of stampmill, which has since become standard in Nova Scotia gold mines. This mill, unique in its design and operation, is specially adapted for the most efficient extraction and recovery of gold as it occurs in our Nova Scotian ores. It is commonly known as the Underwater Feed type, as opposed to the usual Overwater or Top Feed type, and it may be rightly termed The Nova Scotia Self-Classifying Stamp Amalgamation Mill. It is conceded by experienced mill-men that it is superior to any other type of mill for recovering the very coarse and granular gold typical of the ores of this Province. The particular installation and practice to be described in this paper is that of the Guysborough Mines, Limited, at Goldenville, Guysborough county. Emphasis will be laid on certain operating innovations of extreme simplicity and high efficiency.

Jan 1, 1935