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By L. Kong, V. G. Papangelakis, L. Li

"The Eh-pH diagram of lithium-titanium-water system at 25°C, 100 °C and 200 °C was constructed. It shows that there exist thermodynamic stability areas of Li2TiO3. This indicates a thermodynamic possibility for the formation of Li2TiO3 in aqueous solution. A hydrothermal process has been applied for the preparation of Li2TiO3 using TiCl4 and LiOH•H2O as raw materials. The prepared samples were examined with X-ray diffraction, scanning electron microscopy and thermo-gravimetric analysis and differential scanning calorimetry. The results show that temperature and washing condition have significant effects on the phase composition of the product. Phase-pure Li2TiO3 powders were obtained at 200°C with Li:Ti molar ratio of 2.0.INTRODUCTIONLithium-containing ceramics enriched in 6Li, such as Li2O, LiAlO2, Li4SiO4, Li2ZrO3 and Li2TiO3, are considered as tritium breeding materials (Saito et al., 1998; Roux et al., 1998; Johnson et al., 1998; Hoshino et al., 2002). In view of its admirable properties: low-activation, good thermal stability and thermal conductivity, excellent tritium release performance and reasonable lithium atom density (Kopasz et al., 1994; Roux et al., 1996; Saito et al., 1998; Wu et al., 2008), Li2TiO3 is recognized as one of the most promising candidates of tritium breeding materials. Meanwhile, Li2TiO3, as the precursor of H2TiO3-type lithium absorbent, receives more attention as the development of extracting lithium from salt lakes (Zhong, 2004; Zhang, 2010).Several synthetic techniques have been applied to prepare Li2TiO3 powders, such as solid-state methods (Lulewicz and Roux, 2002; Ramaraghavulu et al., 2011; Mandal et al., 2012), sol-gel processes (Deptula et al., 2002; Lee, 2008) and solution combustion routes (Cruz et al., 2006; Jung et al., 2006; Sinha et al., 2010). A solid-state method may produce a series of problems, including impurity contamination and difficulty in morphology control of the obtained powders, although the process involved is simple. The solgel process is prolonged and usually demands for multi-step reactions, while solution combustion route requires plenty of energy and easily causes product contamination by the fuel used. Owing to its environmentally benign and highly suitable characteristics in fabricating materials, hydrothermal technology has been widely used and became a powerful tool in the field of material synthesis (Yoshimura and Byrappa, 2008). For example, ZnO in the form of bulk single crystals, fine particles and thin films, which is an attractive photoelectric material, was successfully synthesized by hydrothermal process (Sekiguchi et al., 2000; Ohshima et al., 2004). A hydrothermal technique was also used to the preparation of carbon nanotube, which possesses outstanding mechanical, structural and electric properties (Bernholc et al., 1997), and is superior to the commonly used method (Gogotsi and Libera, 2000). There, it provides an option for preparing Li2TiO3. Laumann et al. (Laumann et al., 2010) synthesized cubic a-Li2TiO3 by hydrothermal reaction at 180 °C for 18 h, using TiO2 powder, comprising of anatase and rutile, and lithium hydroxide in de-ionized water. However, the prepared a-Li2TiO3 is extremely unstable with a maximum lithium loss of 75% when treated in bathing experiment."

Jan 1, 2012

By Guy Demers

"This paper defines the responsibilities and functions of the Maintenance Department, and its organization, physical and human assets, highlighting the unique operating problems. Due to the self-sufficient aspect of the Asbestos Hill Deception Bay project, the Maintenance Department cover-s fields that are numerous and very dissimilar: production, mobile, processing, service, power generation, fire protection, heating, water and sewage disposal equipment. Added to this, buildings, plant and camps, wharves and communications equipment all demand versatility, adaptability and expertise from maintenance personnel. Good maintenance practices are a necessity in this environment and are more critical than at southern locations; that is, high-quality replacement material, complete and well-controlled preventive maintenance, major repairs on a component-replacement basis, updated inventory, efficient training and permanent contacts with suppliers, combined with an equipment improvement program, updated specifications on lubricants, hoses, seals, filters, etc., are mandatory. The seasonal aspect of the operations applies a great deal of pressure on the maintenance team, as the production months do not permit major repairs. Short- and medium range planning and accurate evaluation of equipment conditions highly influence production efficiency. Maintenance control, planning and scheduling do not follow the accepted standard routines, as personnel turnover normally does not permit an accumulation of knowledge of the equipment history and condition by the •individual tradesman."

Jan 1, 1976

By Henry C. Knight

A number of improvements in the techniques of budgetary control have been developed in the 1970's. The most significant of these is zero-base budgeting. This procedure is a marked improvement, because it overcomes some of the key weaknesses inherent in most traditional approaches to budgeting. It incorporates techniques and disciplines which improve the quality of both the budgeting effort itself and the documents that most senior managers will need to evaluate. The end result is a budget that establishes and improves cost effectiveness. This budget is based on resource allocations using cost-benefit criteria and on a system of prioritization for making funding choices. Zero-base budgeting is applied only to costs and expenses that are not conducive to control using industrial engineered standards. Therefore, the benefits attributed to zero-base budgeting will only hold true for administrative, selling, exploration, safety, fire protection and overhead, and other indirect types of costs and expenses. It is in this context that the question of its attractiveness for the mining industry is dealt with.

Jan 1, 1978

By A. Alfantazi, M. Mahon

The current efficiency in zinc electrowinning is a key indicator of the performance in a cell house. This is typically measured by comparing the weight of the cathode to the electric current applied over the deposition period. This calculation can be cumbersome because the deposition history of each pulled set of cathodes will be unique. It will depend on the applied current and electrolyte conditions from onset of deposition until the cathode is removed and stripped. Not accounting for these can introduce errors to the calculated current efficiency. To track this history and reconcile the current efficiency, a time based computer process simulation was made of an industrial cell house. Two months of hourly recorded measurements from the cell house were input to the simulation, including current to the cell houses, concentrations, flow rate, and temperature of the purified leach solution. The simulation’s predictions of the concentration of zinc in the circulated, spent, and returned electrolyte all showed good agreement with the industrial data over the two months giving a validated zinc balance. The simulation was then tuned to predict the instantaneous current efficiency for all times, as well as the expected masses for the deposits given their deposition history.

Jan 1, 2014

By G. Reuben Yourt

THIS paper is chiefly a description of the improvements in dust control chat have been brought about in the assay office grinding room at Wright-Hargreaves. The fume exhaust systems are briefly included because they also are important to the health of the employees. There are three chief factors which determine the efficiency of a dust control system: First, the amount of time and thought spent in designing it. Second, how close! y it is kept up to date with the growth of the plant-a system that is adequate for the number of machines operating when it is installed may fall short of fulfilling its purpose as the plant expands. Third, unless someone is held directly responsible, a system is likely to get out of repair and gradually lose its efficiency-this can easily be detected by regular dust surveys. In designing the present system at Wright-Hargreaves, the object kept in mind was to reduce the dust concentration of all operations to a safe limit, chat is, well under 300 particles per cubic centimecer of air. By doing this, a condition would be attained chat would make it possible to discontinue the use of respirators, which at best are not very comfortable and do not remove all of the hazardous fine-dust particles.

Jan 1, 1941

By J. E. Dutrizac, J. B. Sunstrum

Until relatively recent times, virtually all gold was recovered by gravity and/ or amalgamation methods. Although such techniques are very effective on coarse gold, they become increasingly less useful for finer grains especially when the gold is partly enclosed in rock matrix. Throughout the nineteenth century a number of bonanza gold fields were found in the United States, South Africa, Australia and Canada. In every case the abundant supply of gold nuggets and coarse alluvial gold soon gave way to hard rock mining with its inevitable losses of fine gold in the stamp mill tailings. Continuing efforts to develop new technologies capable of dissolving gold from finely ground ore were eventually successful first with chlorination (the Plattner process) and subsequently with cyanidation. Even before the nineteenth century, however, European chemists such as Scheele and Berthollet were aware that gold could be readily dissolved in an excess of free cyanide(1). As early as 1840, a patent was issued to the Elkington brothers for the dissolution of pure gold in cyanide solution and its subsequent plating onto various metals, with or without an applied electrical current. In 1846, Elsner showed that oxygen was also required to solubilize gold or silver in cyanide media(1). Despite the fact that much work was done on the reaction of cyanide solutions with gold, a viable leaching process for gold ores did not quickly emerge although cyanide solutions were used to enhance amalgamation from the 1860s onward. Major problems were associated with the use of concentrated cyanide solutions; the costs of cyanide were excessive and it was difficult to recover gold from the concentrated media.

Jan 1, 1999

By M. D. Vance, G. R. Corbett, S. D. Butt

Surface wave imaging is a relatively new seismic technique that generates subsurface depth images without having to drill boreholes into the ground, and is rapidly becoming a standard tool in non-destructive geotechnical characterization. This paper presents a case study of the application of these surface wave techniques to image shallow abandoned mine workings at the Montague Gold Mines district near Dartmouth, Nova Scotia. This district has numerous steeply dipping narrow vein workings from historical mining activity, and has actively subsiding and collapsing crown pillars. Due to the rugged conditions at the site and the relative narrowness of the openings (often less than 1 m), a surface seismic system was developed that had improved portability and lateral resolution over other available seismic imaging systems. Seismic surveys were conducted over two sites where independent evidence indicated the presence of shallow mine workings. At one site, a comparative gravity survey was also conducted. The seismic data was processed to generate velocity vs depth images. Overall, the velocity images show vertical zones of zero velocity in the same lateral positions where historical mapping, current subsidence and gravity surveys indicate the presence of steeply dipping workings. Further, the velocity sections are consistent with the thickness of the till cover at each site and the possible weakening of crown pillars at one of the sites.

Jan 1, 2005

By G. W. Norval, V. G. Papangelakis, G. A. Moldoveanu

Smelting has been the primary method of treatment for refractory copper sulfide concentrates such as enargite (Cu3AsS4), but the pyrometallurgical processing generates elevated levels of volatile arsenic. The present research investigates a novel hydrometallurgical process of oxidative dissolution of enargite at ambient conditions in the presence of chlorine dioxide (ClO2), a very powerful oxidant generated in solution by the reaction between a strong acid (HCl or H2SO4) and sodium chlorite (NaClO2). The effects of initial oxidant concentration, particle size, agitation speed and temperature on dissolution kinetics and copper extraction were investigated. It was found that a stoichiometric ratio of ClO2:Cu3AsS4 = 9:1 were needed to completely and congruently dissolve the mineral with fast kinetics (<15 minutes) under ambient temperature. The dissolution extent (metal extraction) increases with increasing ClO2 concentration and decreasing particle size of solids, but is not influenced by temperature or agitation speed.

Jan 1, 2014

By N. B. Brown

ABSTRACT The effect of a low4emperature stress relief at 232.2°C. (450°?F.) on the fatigue properties of shot-peened SAE. 1080 steel has been investigated. Specimens of the steel were first annealed. One half of the steel bars were then normalized and the other half were water-quenched and drawn. Specimens of the steel with each heat treatment were tested in tensile, notched bar impact, and fatigue. The fatigue specimens were test in air and water in R. R. Moore high-speed rotating bending machines in the following conditions: un-peened, peened, and peened-and stress-relieved at 232.2°C. ( 450°F.) The &apos;endurance life&apos; and fatigue properties of specimens given a stress relief heat treatment after shot peening were superior to those of specimens given a smooth machine finish or shot peened. INTRODUCTION THIS investigation was initiated to obtain preliminary information on the effect on the fatigue resistance of shot peening the machined surface of a high-carbon steel similar in composition to that used in hollow drill steel. The data obtained in this investigation could be applied in analysing the application of shot peening hollow drill steel shanks. It is well known that the &apos;endurance life&apos; and fatigue limits of steel are greatly ?improved by shot peening. References to this in the literature are numerous.

Jan 1, 1951

By F. Rivard, M. G. Drouet, W. S. Ruff, P. Carabin

"In both the hot rotary-salt-furnace (RSF) treatment of aluminum dross and the cold ball-millsieving (BMS) treatment of zinc dross, enormous amounts of energy and recoverable metal are wasted and large amounts of greenhouse gas are produced. Such wastes and the environment pollution could be avoided by using the DROSRITE PLUS™ technology. Economic and GHG production comparisons between the presently used industrial treatment processes and DROSRITE PLUS™, supported by over one hundred tests conducted in Canada, the US and Europe, are presented. The savings, with DROSRITE PLUS™, would be about $191 and $418 per MT of aluminum and zinc dross, respectively.INTRODUCTIONDross is a material, which forms on the surface of molten non-ferrous metal, such as aluminum or zinc, during melting, metal holding and handling operations when the molten metal is in contact with a reactive atmosphere. Dross normally consists of metal oxides entraining a considerable quantity of molten free (unreacted) metal, and for economic reasons it is desirable to extract the free metal before discarding the residue. In the case of aluminum dross, recovery of the metal is usually carried out by treating the dross in a furnace at a high temperature (Peterson et al., 2002). By contrast, cold zinc dross is crushed in a ball mill followed by sieving to separate the coarse metal portion from the fine oxide residue.The conventional aluminum dross treatment process, using gas or oil-heated rotary salt furnaces (RSF), is thermally inefficient and environmentally unacceptable because of the salt slag and CO2 produced from the combustion of fossil fuels. In the past several years, a number of salt-free processes have been developed and some of these have found limited commercial use (Gripenberg et al., 1994; Lavoie et al., 1990). In all these dross treatment processes, heating of the cold dross in a rotary furnace requires an external energy input that varies between 375 and 2,500 kWh per (metric) tonne of dross. Molten metal separated during processing of the heated dross is tapped, and the remaining solid residue is discharged from the furnace."

Jan 1, 2012

By W. B. Agocs

"IntroductionWITH THE DISCOVERY of natural radioactivity at the end of the 19th century, and the design of equipment for the detection of this phenomenon, radioactivity surveys bad their inception. Early in the 20th century it was found that almost all rocks are radioactive to a certain degree. This radioactivity is due to the nuclear disintegration of six naturally radioactive elements: potassium, thorium, uranium, rubidium, samarium, and lutecium.The radioactivity of these elements manifests itself by the emission of some concentration of alpha, beta, and gamma 'rays'. Of these, the alpha and beta 'rays' are, respectively, helium atoms and electrons, while the gamma 'rays' are short wave length x-rays generated in the nuclear disintegration by the transformation of mass into energy.The alpha and beta rays, being particles of matter, are stopped ve• easily by material barriers, but gamma rays are extremely penetrating and they will pass through a foot or more of rock or several inches of lead.The radioactivity may be detected by the causing of ionization by the radiation. The radiation detectors may be divided into four classes: ionization chambers, proportion al counters, and Geiger counters, all of which use gas for ionization, and scintillation counters, in which a solid is ionized. The basic principle of all these detectors is the same; the difference lies in the method used to measure the degree of ionization produced by the rays. Currently, the scintillation counter is displacing, the other instruments in radioactivity surveying."

Jan 1, 1955

By E. Herrera, L. Mariscal

"Ilo Copper Smelter operates since 2007 with an ISASMELTTM furnace as a single smelting unit (1,200,000 tpy) associated with two Rotary Holding Furnaces for separation of matte and slag, and which directly produces a discard slag. Southern Peru continually has been improving the slag chemistry of its ISASMELTTM furnace in order to reduce copper losses, given its big economic impact due to large slag mass generation. The present paper describes the influence of the CaO, Al2O3 and magnetite content in the slag of the ISASMELTTM furnace correlated with the SiO2/Fe ratio and its liquidus slag. Also it defines the best slag chemistry and operating practice in order to reduce the copper losses without compromise the bricks life of the furnace.INTRODUCTIONIlo Copper Smelter of Southern Peru (Grupo Mexico) is located on the southern coast of Peru, and treats mainly copper concentrates produced in its own mines (Toquepala and Cuajone).The modernized smelter was commissioned in 2007 and operates with an ISASMELT™ furnace as a single smelting unit (1,200,000 tpy), which is associated with two Rotary Holding Furnaces (RHF) for separation of matte and slag. This slag is directly sent to the dump. Figure 1 shows the smelter flow diagram.The ISASMELT™ process is a bath-smelting process using a single lance. The lance tip is immersed into a molten slag bath contained within the stationary, vertical, refractory-lined ISASMELT™ furnace. The injection of oxygen-enriched air, through the lance into the slag results in a highly turbulent molten bath. Feed material falling into the turbulent bath from above reacts rapidly, resulting in extremely high productivity for a relatively small bath volume."

Jan 1, 2012

By M. C. Walton, W. Roelofs

ABSTRACT: In most cases, a refractory repair involves dealing with used refractory linings above shoulder height, defining these as overhead refractories. This paper details a method of personnel protection involving a low-pressure inflatable balloon system, installed to prevent the dislodgement and freefall of in-situ refractories. This system has been successfully applied to numerous types of vessels in the process industries in the last three to four years. This paper, prepared for the CIM Conference of Metallurgists held in Vancouver, British Columbia in October 2010, outlines details of the system and gives examples of successful applications.

Jan 1, 2012

By K. D. Genn, A. Mucha

This paper deals with Hilton Mines' approach to the maintenance of wear items such as truck boxes, shovel buckets, tractor pads, crawler sprocket idlers and the drop-ball. Each will be given a brief. description as to application, design, kind of materials involved and type of wear. The maintenance procedure is then outlined in terms of materials used, preliminary preparation, and welding and machining practices. The service history of new and re-paired items and the relative economics of repair vs replacement will then be presented.

Jan 1, 1969

By Matthew Blecha

The Tribag copper deposit is one of the rare examples of mineralized breccias in the Canadian Shield. The breccia is a pipe-like body, and consists of granitic, diabasic and volcanic fragments embedded in a vuggy, quartz-carbonate matrix. The mineralization is essentially chalcopyrite and pyrite, with minor molybdenite, sphalerite, galena and other sulphides. The main ore zone is saddle-like in shape, and is enveloped in a zone of chloritization, sericitization and clay-mineral alteration. It is suggested that the breccia is of the diatreme type. Introduction T HIS paper is based on eighteen months of field work, including surface and underground geological mapping and core logging, and on the survey of relevant literature. No significant amount of laboratory work has been done as yet. Location and Access The Tribag Batchawana property is located 40 miles north of Sault Ste. Marie, Ontario, about 10 miles east of Lake Superior. A 17-mile, all-weather road connects the property to the Trans-Canada highway to the south, and 4 miles of a 12-mile road remain to be completed to link it to the Algoma Central Railway to the northeast.

Jan 1, 1965

By V. Ushakov, P. Bogdan

Daily production scheduling in a highly dynamic smelter environment has always been a great challenge for the operation management due to a significant amount of uncertainties. Planned and unexpected equipment failures, various energy outages, inaccuracies in flow and mass balancing, manpower availability conflicts and other constraints make the job of daily production planning exceptionally difficult. This paper discusses a general scheduling approach utilized by the production management of the Phelps Dodge Miami Smelter (the Smelter). It also describes logical assumptions and some practical software solutions that have been exploited by the Smelter managers to assist the front line supervisors in dealing with daily planning activities for several years.

Jan 1, 2007

By T. G. Joseph, M. Welz

ABSTRACT: Joseph (2002) introduced passive seismic monitoring to measure mining equipment performance. This paper evaluates the potential of passive seismic monitoring to correlate mining equipment operation with oil sands surface response, with a mining hauler as the seismic source. When applied to moving haulers, this action–reaction approach is complex. Vibrations from on-board equipment, such as pumps and tires, dirty the signal with noise. To facilitate any correlation, the signal must be cleaned up. Existing geophysical analytical techniques were manipulated to evaluate the noise problem and to filter sufficiently to permit an evaluation of whether a mining equipment action–ground response relationshipis in fact discernable.

Jan 1, 2011

In several European countries, including Russia, it has become economically attractive to utilize peat as a fuel for power generation, the production of metallurgical coke, the production of fuel briquettes for the domestic market and low-Btu gas. Although the economic base and availability of energy supplies in Europe is much different than it is in Canada, regional economics here may warrant the development of peat as an alternative source of energy. Canadian peatlands cover several thousands of square miles and have historically been considered as waste land. Now, with the increasing costs of other energy sources, it is apparent that fuel peat should be re-evaluated as a potential energy resource. A nation-wide inventory of peat deposits has been prepared and reserves evaluated for some of these areas where field surveys have been carried out. The paper describes alternative mining methods developed to meet some of the various conditions encountered on virgin peatland . These mining techniques are generally based on current peat technology exercised in other parts of the world and would be applicable in some of the peat regions of Canada. Cost estimates have been prepared for peat production in regions of Canada, and the socio-economic aspects of a large-scale fuel peat operation are discussed. Several potential utilization schemes have been described, with particular emphasis on electric power generation. The paper makes recommendations for steps to be taken in the development of a fuel peat industry in Canada.

Jan 1, 1978

By A. Oja, M. Lahtinen, P. Salonen, B. Saxen

Most of the secondary and low grade zinc raw materials cannot be treated successfully by either conventional roasting - leaching - electrowinning (RLE) process or even by atmospheric direct leaching process. The problems arising especially from high impurity content of these raw materials can be effectively solved by implementation of the solvent extraction process. The utilization of solvent extraction process has been demonstrated by Outotec with raw materials like Waelz oxide, crude zinc oxide and zinc containing concentrator tailings. Based on batch and continuous test work it has been shown that SHG quality zinc can be produced even from the lowest grade raw materials. Impurity control in the solvent extraction process has been examined. The solvent extraction process is the key feature of the whole zinc plant for such raw materials. However, design of the entire zinc process including neutralization and bleed treatment is important for optimization of investment and operation costs of the plant. Very careful evaluation of the zinc process with modern simulation tools is essential. The optimized Outotec zinc process ensures a sustainable and profitable process containing minimal effluent and requiring little residue treatment.

Jan 1, 2014

By Mel Torrie

1 Want access to low level vehicle data so 3rd party apps can be applied as desired 2 Hardware Agnostic (COTS plug and play) 3 Common/Open protocols that facilitate integration and the coexistence of a variety of applications on a variety of equipment 4 Minimum computer hardware footprint 5 Technology Independence (including comm. backbone)

May 1, 2013