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By Walter Greaves

THIS paper describes a series of tests performed at the Hollinger mill during the past four years, in which both metal and rubber-lined pumps were used for pumping sand and slime. While conditions will not be the same at other mills, it is felt that the information gained from the tests should be of value to other operators and of assistance to them in selecting the most efficient size of pump and kind of lining for economical operation. For the successful operation of pumps with rubber linings there are certain conditions, which, if recognized at the outset, will save the operator a good deal of work and trouble. First is the necessity of keeping sharp pieces of steel, or anything that might cut the lining, out of the pumps. This can be effected by placing screens in the proper locations. Second is to recognize the fact that the rubber lining of the shell, and the rubber cover of the impeller, are subjected to very different conditions. The shell lining, :being at rest and well supported by the metal case, has a relatively easy job compared ? with the impeller covering, which is subjected to centrifugal force and has a tendency to tear itself away from the metal core. Also, the pulp travels through and past the impeller at a high velocity. These two factors, centrifugal force and velocity of the pulp, would appear to set a limit to the speed at which, for a given set of conditions, it is economical to run a rubber-covered impeller. Therefore, a pump should be large enough for the work to be done. To get the best mechanical efficiency, it must be operated somewhere near the limit of its capacity, but this may not give the best overall cost, because the saving in power, due to the high efficiency, may easily be lost through excessive wear on the lining. It would appear that this condition is more critical in a rubber-lined pump than in one lined with metal.

Jan 1, 1939

By Lan Vu

"The Ferderber mine consists of a series of Archean gold-bearing quartz lenses within a shear zone that crosscuts the central part of the quartz diorite Bourlamaque batholith. This zone has sharp contacts with the enclosing quartz diorite, and on average strikes N70E and dips 65SE. Along the contact with the shear zone, the quartz diorite is chloritized, sericitized and carbonatized. The chlorite schist within the zone is probably derived from mafic dykes.The geometry and distribution of structural features within the Ferderber shear zone suggest a long history of repeated movements. The majority of gold-bearing lenses were first emplaced during a probable early period of brittle shear which resulted from strike-slip movement. They were then folded and pulled into boudins by a later episode of reverse movement that accompanied ductile shear. New mineralized veins were emplaced in the shear zone and deformed at this time.Mineralized veins are dominated by quartz, carbonates, tourmaline and micas. Gold is more common within pyrite where chalcopyrite is abundant and is generally in contact with both pyrite and chalcopyrite at ""triple point"" grain junctions. This intimate association suggests that copper may have played an important role in gold deposition.Recent exploration has shown that the Bourlamaque batholith is cut by many parallel or en echelon shear zones. Study of ""Landsat"" and aerial photographs has indicated a number of linear structures striking ENE-WSW and ESE-WNW which form a conjugate system. The intersection of these two structural trends presents an interesting exploration target."

Jan 1, 1990

By Karl J. C. Harries

"14.1. INTRODUCTION1The boilerplate of an agreement is not a single provision, but a series of provisions that are expected in “every agreement”. They are sometimes also referred to as the “lawyer’s provisions”. Many businessmen consider the boilerplate to be superfluous and, to some extent, window-dressing by the lawyers – even legalese. They will often offer advice to the effect that it can “pretty well be ignored”. Such advice could not be more wrong.Most boilerplate provisions are essential parts of every agreement. Some may be part of a “standard package” and may have little relevance to the agreement at hand, but these are the exception rather than the rule. The exceptions should not be treated as justification for giving all these provisions short shrift. The boilerplate should receive the same review, consideration, and negotiation as the provisions that set forth the business deal. It is often these provisions that make the deal work or that are turned to at the time of disputes. If they are inadequate, as they sometimes are (unfortunately, some draftsmen are also loath to review or update their standard boilerplate provisions or to tailor them to the deal at hand), they can create problems, rather than offer solutions. Such problems can be costly and time-consuming for the parties to address. Inadequate or incomplete provisions may ultimately be one of the reasons for the parties to turn to the courts to settle their differences. On the other hand, good boilerplate provisions can help keep them out of the courts.One of the principal objectives of an agreement should be to provide procedures, or mechanics, for implementing agreed principles and for the parties to follow to settle their differences, real or perceived, without going to the expense and disruption of a lawsuit. An agreement should aim to keep the parties away from the courts, not serve as a springboard to the courts. It must nevertheless be acknowledged that, if there is a major falling-out among the parties to an agreement, the chances are that, however carefully the provisions of that agreement have been negotiated and drafted, the parties will end up before the courts or some other adjudicating body."

Jan 1, 2003

By J. E. Dutrizac, J. M. Zinck

Ferrihydrite is often the initial precipitate resulting from the rapid neutralization of Fe(III) sulphate solutions, and it seems to be a major constituent of zinc plant neutral leach residues. The most important parameters affecting ferrihydrite precipitaton are temperature, solution pH and the neutralization rate. Low temperatures and rapid neutralization rates yield poorly filterable ferrihydrite, whereas higher temperatures and slower neutralization rates produce readily filterable precipitates; in all instances, however, the precipitates are two-line ferrihydrite. Significant amounts of Zn are incorporated in the ferrihydrite precipitates, and the Zn contents increase with increasing Zn concentration, pH or temperature. Generally, the sulphate contents of the precipitates decrease as the Zn contents increase, and this may indicate that the Zn is adsorbed on the ferrihydrite. Discrete Zn phases were not detected. Neither Cd nor Tl is precipitated with ferrihydrite, although thallium jarosite co-precipitates with ferrihydrite at high Tl concentrations and elevated temperatures. Virtually all of the Sn added to the solution precipitates with the ferrihydrite, but the tin is believed to be present as intimately admixed amorphous SnO2.nH2O. Although selenite extensively precipitates with the ferrihydrite, selenate remains mostly in solution, likely because of the close similarity of the SeO4 2- ion to the SO4 2- ion which is present in high concentrations and saturates the available sites for anion adsorption.

Jan 1, 1998

By W. H. Gross

To pollute means to make impure or unclean. We tend to forget that man defecates, urinates, sweats, expectorates and exhales and in himself is a beastly little pollutor-but then so is Mother Nature! The object of this paper is to try to put what man and nature do into perspective. The facts indicate that although man may sweat a little, Ms. Nature is by for the greatest pollutor of all.

Jan 1, 1979

By D. Janney

Kennecott's Utah Smelter commenced operations in June 1995 utilizing Outokumpu Flash Smelting (FSF) and Kennecott-Outokumpu Flash Converting (FCF) technology. After some initial teething and equipment problems the smelter achieved its design capacity in mid-1997 and now processes over 1.0 million tonnes of copper concentrate per year with exceptional environmental performance. The smelting furnace has operated for 11 years and the converting furnace for 5 years without major shutdowns. The first major smelter shutdown commenced in September 2006 after extensive planning. The FSF was completely re-bricked and the latest above and below bath containment systems installed. The FCF was inspected and re-bricked with some improvements made to the above bath containment system. The FCF life is now anticipated to be the same as the FSF. Numerous improvements and modifications were made to the rest of smelter facility including extensive upgrades to the dry electrostatic precipitators. Production ramp-up was smooth with the smelter now frequently operating at acid plant capacity.

Jan 1, 2007

By M. W. Wadsley

"Physical and chemical property models are widely used in process engineering. There exist, in the published literature, completely empirical models of ''thermodynamic properties"", that is, property models that are not consistent with the laws of thermodynamics. There also exist property models that purport to be thermodynamically consistent but are flawed in their implementation. There are also published property models that are consistent with the laws of thermodynamics but that do not reproduce property values with an acceptable accuracy. A practicing engineer might be asked to assess very different property models for which there are a variety of claims. This paper discusses features of thermodynamic and empirical property models that may assist in their practical evaluation and implementation."

Jan 1, 2005

By N. Wachgama, J. P. T. Kapusta, R. U. Pagador

The Thai Copper Industries smelter (Thai Copper) is located some 200 km southeast of Bangkok near the MapTaPhut deep sea port in one of the industrial centres of Thailand. Although construction of the complex started in the mid 1990s, the smelter, acid plant and refinery were completed in 2004. Thai Copper is a state-of-the-art copper smelter processing imported concentrates with a total yearly capacity of 165,000 tonnes of cathodes. It employs the El Teniente Technology where concentrates are blended and smelted continuously in a primary smelting reactor to produce high grade matte or white metal. The white metal is converted in batches to blister copper in Hoboken siphon converters equipped with Air Liquide Shrouded Injector (ALS I) Technology for sonic injection of oxygen enriched air. Final refining is carried out in two anode furnaces prior to anode casting and electrorefining. Thai Copper and Air Liquide Canada executed a technical assistance agreement in late 2005. Pre-commissioning of the shrouded injectors took place in July and November 2006 while hot commissioning occurred in December 2006. This paper presents the major technical aspects of the joint commissioning, including the establishment of operating practices specific to shrouded injection converting. Preliminary results of this first commercial implementation of ALSI Technology in copper converting are also provided.

Jan 1, 2007

By R M. Ennis, J. C. Botham

This paper is one of a series pre-pared to study the role of fuels and reductants in metallurgical processes, especially from the viewpoint of Canadian requirements. The object of these studies is to provide a reason-ably authoritative interpretation on the interrelation of fuels in light of the considerable changes that have taken place in the Canadian energy field during the past few years. Previous papers in this group have dealt with the problem generally, and specifically in terms of the development of the iron and steel industry of Western Canada. These latter papers, presented at the Symposium on Iron and Steel in Western Canada held in Edmonton, Alberta, on September 8-9, 1959, surveyed the ferrous processes of interest for use in Wes tern Canada, especially with regard to solid fuel requirements. At that time it was evident that there was a need for a similar study of the fuels aspect of the non-ferrous metals industry.

Jan 1, 1961

By Ken McIntyre, Trodel Wolf-Dieter

"Sirius Minerals is a UK based fertilizer development company focused on advancing into operation its polyhalite project in North Yorkshire, England. The operation is known as the Woodsmith Mine which has an estimated 2.7 Billion Tonnes of reserves and is currently in the construction phase. DMC Mining Services was selected to carry out the construction of four shafts for the project, a production shaft of 6.75m diameter to a depth of 1594 m, a ventilation shaft of 6.75 m diameter to a depth of 1565 m, and two additional shafts to support the construction of the material transport system (the MTS and Lockwood Beck intermediate) to 360m in depth for servicing the underground conveyor network for transport of product from the mine site to the costal port facilities located at Teasside. This paper will review the status of the project to date and the innovative approaches that DMC is utilizing to ensure a safe and successful shaft sinking project. INTRODUCTION The Woodsmith Mine in North Yorkshire is a Sirius Minerals-owned deep potash and polyhalite mine located near to the hamlet of Sneatonthorpe, Whitby in North Yorkshire, England, approximately 75 km east of York. The area of interest is more than 700 km2. The £3.2 billion project is to develop the Woodsmith Mine to extract polyhalite, and a tunnel system to transport it to a materials handling facility and harbour at Teesside. The site is the world's largest and highest-grade deposit of polyhalite and is expected to produce 20 million tonnes of polyhalite, potash and POLY4 per annum, as well as create over 1,000 direct jobs and many more indirectly. It has the potential to generate over £2 billion of annual exports for the UK. As the project will require mining to be undertaken in the North York Moors National Park, many objections were raised about the mine. Sirius Minerals has gone to great lengths to ensure that the project is sensitive to the local landscape, including: mineshaft head frames that will be positioned below ground to reduce their visual impact; surface buildings will be kept to a minimum; and the entire site will be landscaped and screened by existing woodland to blend in with the surrounding area. The project will also abide by strict environmental limits which govern our activity during the construction phase."

Jan 1, 2019

By Richard E. Barrett

SOME YEARS AGO I was associated with a mining operation which, because of its isolated location, burned wood for heating purposes. Year after year the tractors and tucks hauled the cordwood in from the edge of the ever-growing clearing. Each year the cartage costs became greater. The degree to which transportation distances affect the economics of fuels obviously varies with many factors, but the main criterion is the amount of heat a unit weight of the fuel will produce. For in-stance, wood is limited in most cases to a haulage distance of a few miles. Coal can be shipped hundreds of miles, whereas petroleum and gas ?can be transported thousands of miles. The world is now on the brink of having a new fuel -uranium. It has the virtue of being so concentrated that transportation costs can, for all practical purposes, be disregarded.

Jan 1, 1958

By Arthur M. Whiteside

Discussion of the laws bearing upon the economics of mining in this province at once resolves itself under three headings: (a) The rights and obligations of holders of mineral bearing lands; (b) Taxation of mines; (c) Regulation of methods adopted in financing mining operations. Titles: The law relating to titles is contained in the Mineral Act, Placer Mining Act and Coal Mines Prospecting Act. Origin: Mining laws in force in this province and elsewhere on the continent had their origin in the rule-of-thumb regulations adopted by prospectors themselves, when, far from the centres of civilization and the seats of the courts of justice, they found it necessary, for mutual protection, to fix the conditions of possession by right of location, and to prescribe the duties to be performed in order to enable the individual to maintain his ground against all comers. These regulations have been codified and added to by legislatures, until we find adequate protection and safeguard to property in the laws of this province.

Jan 1, 1924

By Ozdemir. O.

Magnesium additions to aluminum enhance strength and hardness, lowering density, and improving corrosion resistance. However, during melting and casting processes, significant amounts of magnesium are lost due to selective oxidation. Preventing these losses would reduce the production cost and improve the quality of the final product. The effects of strontium addition on the oxidation behaviour of aluminum-0.5% and 1% magnesium alloys were investigated by monitoring sample weight gains with time with a thermogravimetric balance at 750°C. Sample cross sections have been examined using Field Emission Gun Scanning Electron Microscope.

Jan 1, 2004

By Martin P. O'Connell

"IT IS INDEED A PRIVILEGE to address a group representing a sector of the Canadian economy so important as is the mining sector. Important, not only today, but certainly of great importance for the future development of Canada, for employment, for our trade balance and indeed, when one looks at what we are calling increasingly an industrial strategy, for the future. Surely mining will have a very significant role to play in fulfilling that. It's of special interest to me, as the Minister of Labour - and I ought to confess at the very beginning that I am just two months into this function - of special interest for me to know that you are giving such attention to labour-management relations. I think it is timely that, from my point of view at least, you do this, because for the first time in twenty four years major revisions of the Canada Labour Code as it relates to industrial relations and disputes settlements are currently in the House of Commons going through their second reading, after an easier introduction and some changes which I would be very pleased to describe later this morning. It is very timely too, I think, that we should be looking at this area because public interest is certainly at a high level. It is not only at a high level but it expresses a good deal of irritation with the current status and procedures and results in collective bargaining and there is some urgent search for more sophisticated or modified procedures for settling differences in labour-management relations. The public wants different kinds of results. I think that is apparent to all of us. They want results in terms of justice and equity on both sides. And it means that a Minister of Labour and certainly governments who often are representing, or are the third party in discussions, have a very important and complex role to play in attempting to create a balance as these two parties come to contracts and come to agreements."

Jan 1, 1972

By Paul Guliov

Potash dominates the industrial mineral scene in Saskatchewan accounting for 44% of total provincial mineral production in 1981. More than 7 million tonnes of potash have been produced annualy in recent years; ten underground mines are presently (1983) active. Sodium sulphate and cement are also important mineral products. Construction aggregates, clay products, bentonite, salt, peat moss and sulphur complete the list of industrial mineral products.

Jan 1, 1984

By G. M. Ross, J. A. Scott, C. A. Laamanen, H. Shang

"Indirect recovery and use of waste heat contained in smelter off-gas is proposed to expand regions available for year-round, on-site production of micro-algae–sourced biodiesel, a fuel that could be used in underground machinery. A dynamic model of an off-gas heat exchanger describes capture and distribution of heat into open, external, rectangular micro-algae ponds. Smelter off-gas contains sufficient energy to maintain large-scale micro-algae cultivation pond temperatures above 15°C, even with winter ambient temperatures below –15°C. Results highlight opportunities that could lie in tapping these heat resources to produce renewable biofuels on-site and sequester CO2 while leaving the industrial process unaffected.RÉSUMÉ On propose la récupération et l’utilisation indirectes de la chaleur résiduelle contenue dans les dégagements gazeux des fonderies pour développer les régions se prêtant à une production toute l’année durant et sur place de biodiesel à partir de micro-algues, carburant dont on pourrait se servir pour le matériel d’exploitation souterraine. Un modèle dynamique d’échangeur de chaleur contenue dans les dégagements gazeux décrit le captage et la distribution de la chaleur dans des bassins rectangulaires ouverts de micro-algues en extérieur. Les dégagements gazeux des fonderies contiennent suffisamment d’énergie pour maintenir les températures des grands bassins de culture de micro-algues au-delà de 15°C, même avec des températures ambiantes en hiver inférieures à –15°C. Ces résultats soulignent les possibilités que pourrait offrir l’exploitation de ces sources de chaleur pour la production de biocarburants renouvelables sur place et pour la séquestration de CO2 sans que cela n’ait d’incidence sur le procédé industriel.INTRODUCTIONMicro-algae that grow in water can efficiently convertsolar energy and carbon dioxide into biomass. This biomass can be up to 50% oils (lipids), which can be extracted and converted into biodiesel through transesterification (Demirbas, 2008). Compared to terrestrial plants that produce similar oils (e.g., jatropha, soybean, and rapeseed), micro-algae represent an order of magnitude increase in areal productivity, do not require arable land, and can be continuously harvested (Rawat, Ranjith Kumar, Mutanda, & Bux, 2013). The potential advantages through the production of biodiesel from micro-algae also include sequestration of carbon dioxide, reduced reliance on fossil fuels, and the co-production of other value-added bioproducts."

Jan 1, 2017

By S. Duvah Pentiah

The transformation of an open pit coal mine to a horizontal-punch underground mine is subject to a number of challenges. These include scheduling the operation of various sizes of trucks over a long period, as well as updating delivery routes and dump site locations as the mine transformation progresses. In this process, rock is excavated from a quarry through earthworks. The bulk earthwork and quarry material delivery were initially drawn from traditional planning and experienced issues in their early phases. As a result, a traffic simulator was developed in order to validate schedules and predict achievable throughput, likely delays or blockages in the long term. The dynamic traffic simulator was also used to provide traffic density and vehicle arrival data at selected intersections in order to identify possible safety and efficiency issues.

Aug 1, 2013

By T. R. Carter, A. C. Colvine

"Rocks of the Grenville Province in southeastern Ontario are currently largely dismissed by many geologists as having little or no potential for discovery of significant deposits of metallic minerals. The present study demonstrates that the area contains numerous deposit types which elsewhere are major metal producers. Therefore, there is significant unrealized potential, especially for gold, zinc, uranium, and possibly copper.The variety of deposits of metallic mineralization include stratiform zinc in marbles; stratabound base metal sulphides in volcanic and sedimentary hosts; gold-quartz veins; quartzmagnetite iron formation; copper-nickel and iron-titanium in intrusive rocks; magnetite skarns; molybdenum in skarns and pegmatites; uranium and thorium in pegmatites, veins, and calc-silicate gneisses; hematite veins; dolomite marbles (magnesium); and barite-jluorite-celestite-galena-calcite veins. There has been significant production of iron, lead, zinc, magnesium, gold, silver, and uranium.The vast majority of the metallic mineral deposits are confined to late Precambrian supracrustal and related intrusive rocks of the Grenville Supergroup. Many of the deposits are stratiform and/or stratabound and occur within units toward the top of major volcanic successions and in the lower portions of younger carbonate-clastic sedimentary successions.Processes responsible for mineral concentration in the area include: (I) syngenetic hydrothermal activity related to both volcanism and sedimentation; (2) epigenetic processes related to diagenesis, regional metamorphism, and igneous intrusive activity; (3) magmatic processes related to igneous intrusions; and (4) supergene concentration and enrichment. The genetic classification of the mineral deposits presented is based on observed geological relationships and these interpreted geneses. The deposit types have counterparts in volcanogenic and sedimentary exhalative, Mississippi Valley type, magmatic, contact metasomatic, and lode gold deposits. Many of the exploration criteria for deposits of these types may be applicable in the Grenville Province, despite the generally high metamorphic grades and complex deformation."

Jan 1, 1985

By H. Abdollahi

Cold rolling is one of the most important techniques in metal forming since the cold rolling products are almost finished product, The product quality of this process is widely influenced by friction in the roll gap; therefore, controlling the friction and other parameters affecting the cold rolling is very important in order to have a product with high quality, Among the cold rolling parameters, the pressure distribution or friction hill within the roll gap is known as the most significant one, In this study, a new software (Matroll), is introduced which can determine the coefficient of friction (COF) and plot the friction hills for an industrial mill, Besides, based on rolling equations, it offers about 25 rolling parameters as outputs. To verify the software operation, the real industrial rolling data was used as inputs, The results (outputs) are in good agreements with the findings of other researchers, The COF values are very reasonable, The friction hill shows that COF is not constant over the whole arc of contact.

Jan 1, 2005

By B. Kenney

For SOFCs, composite cathodes comprising an electronically conducting electro¬catalyst (e.g. LSM) and an conically conducting electrolyte material (e.g. YSZ) are considered to improve the electrochemical performance by extending the active reaction zone to regions beyond the electrolyte-electrode interface, as in the case of conventional cathodes. Interpretation of experimental data for composite cathodes, however, is complicated by the mixed conducting behaviour which results in local overpotential distributions throughout the composite cathode. These local overpotentials depend on many factors, such as the composition, particle size, porosity and thickness of the cathode. Reliable experimental data obtained from composite cathodes requires carefully crafted microstructural parameters in order to minimize the overpotential variations. A mathematical model of a composite cathode was developed using coupled differential equations describing transport and consumption of chemical species, oxygen ion and electrons. Simulations under various oxygen concentrations were used to obtain the reaction order of the oxygen reduction reaction. An apparent po2 dependency was then extracted from the predicted Rp vs P02 data. It was found that this p02 dependency can be significantly influenced by the micro-structural parameters of a composite cathode, primarily due to local overpotential distributions.

Jan 1, 2005