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By P. K. STRONG

AS an evidence of the fact that mines safety is not being neglected even in the remote district of the Philippines, a short account is appended of the organization and activities of the Mambulao-Paracale District First Aid and Mine, Rescue Association, whose headquarters are at Jose Panganiban Cam, Norte P. I. The second annual miner?s safety celebration which is sponsored by the Association was held in Paracale on Sept. 2, 1940. The event is the big occasion of the year when the thousands of employees of the mines in the district meet to compete for prizes and has become a great social function as well.=

Jan 1, 1941

By Dhanesh Chandra

[The U.S. Ucparunent of tlIe III LeriOr, Bureau of 1?Ilnes, lnta dcvcltil- (I a m.?tl,nd to extract nickel, i:ob.tll and IlIIicr Valuc:l,1, mrl?tl., lrom I.ow grad:, dumusI it Inlet itc.: :isin;; a rarb-i mnnnxid:: reducl.iun and ,innnonln/mumonlum sull,h.Ito Icitcll Col lowed by solved. evil let foil and clot tr:,winnfu,;. 'I 'o rain bcLtur undcI'sLandin;; uI the producLs reduced rind leached with the s;:Item, the liureau of t?Ilite; was enf,ngod In a 1 uinL sl.utly IIt1I the Uuttvcr ltc~:c:n-ch LnstiI-IL-. 'I'hr'ut;;h C(Im:drlod ahplit I¬L ion:; of a rotnbIW)L11nl ill eleu Lyon :utJ uplical inicrnscopy, cle trun beau micru,inal?;st?s and X-r.iv tcchnitlaes, Lhc factors jilt] ucncing low nickul e::lracl.on yLrids Iron, ccrlnin l;tteritos wul the hcuefhe al yCferL front addil.I:un u1. r:u)plowt' ruug,ounus and halides have bucn rrvealod. IL leas ht'en shown their nt nliJcrate Lion terlperuLuri's (5S0°C - 6501C) Lhe 111LACl extraction ylolds were low hccausc of the futmetlt-m of rufrill t,urv sillc:Ite compicxcs during ciii lit Hi [hut COOL.tlu sig nlficnnt anutunls of nickel .Lrui LhaL arc resistant Lu discolullull it, a su6r.C?quent ammnnlIca1 Jcaeh. 'This formation ill rulracLorv rnngtieves is altrlbuU?d Lo the prc.srnCV of aluauinum combined with c.ilicun jn addlt.lon In tnnl;neni~im in I.lic Lalerites, Iligb exII.Ictlon yields were oblalneJ when none or only a few I ,fraCLot' e, were InrmeJ. Hit s;intc rcfrarlnry cowl, Icxc5 also lend Lo surround Ow IaaIIiable meI.allle iron-IIIcI:el :iILoy CIUSisling ill the mau'ix, tIll: rrhv nreveu)Ling cuntacr ,Itlt LI5U Jeacl: solution; this, huwrvcr, ran ho ovu:rcoml by At ti itlon .111.11 retieCtiun. 'I'hc eIIcc l of prr.reJIctlun .,Ill itivi's vucli i's lye iii', ',udlum "Ill orIde, hv,Irogrn CIIInrILIC, etc., and Lht? 1111,Lre:InrLlI'll he'e:tleg un Lbe cxLt,icLitin are also iilsr.ussod 111 Lhe rcl,olt.]

Jan 1, 1979

By E. W. Greig

This paper is an account of exploration for bauxite in the Amazon Basin, Brazil, and particularly of the discovery, exploration and development by Alcan of the Trombetas deposit so a general account of the Trombetas Project has already been published in E/MJ (Anon. 1975) to which the reader is referred for details on owner-ship, infrastructure and construction as well as the proposal for mining and treating the bauxite. It is impossible to consider the Trombetas deposits in isolation. A regional account of bauxite in and around the Guyana Shield and the northern portion of the Brazilian Shield is included and it is suggested that these deposits all formed during Tertiary time under similar conditions.

Jan 1, 1977

By Henry Newton

It may seem somewhat a work of supererogation to present to the American Institute of Mining Engineers, composed largely of gentlemen with whom the subject is so familiar, a paper on iron ores and their distribution. To many of them, however, it possibly will not be without interest, as there may be some, like myself, who hare nowhere found a connected account of the character of the deposits and the circumstances upon which are founded the great iron-producing centres of the world. This blank I have endeavored to fill,

By R Klepper

Separation of leach residue suspended solids from pregnant liquor solution is an important step in hydrometallurgy flowsheets. Alternative flowsheet options are counter-current decantation (CCD) thickeners or counter current washing (CCW) horizontal belt vacuum filters. Extensive sedimentation and vacuum filtration simulations have been completed by FLSmidth on leach discharge slurries to indentify equipment capacity and performance. These data were used to compare Capex and Opex for CCD versus CCW alternatives. In addition, Capex and Opex for large horizontal belt vacuum filters with filtration areas greater than 250m2 are compared to current state of the art sizes of 150m2. This paper presents this information and discusses various advantages and disadvantages.

Aug 8, 2011

By Y Zhu, D J. Williams, M O’Neill, C Zhang, X Lei

A cover of inert material overlain by topsoil is required over compacted, seawater-neutralised red mud, a waste product from the refining of bauxite to produce alumina. The cover is to be revegetated, and it is necessary to demonstrate that the potential evapotranspirative-driven uptake of salts from the seawater-neutralised red mud will not impact the revegetation. An instrumented column was designed and constructed to test the evaporation-driven uptake of salts from compacted red mud into an overlying cover material with a thickness limited to 600 mm. The PVC column is 1.2 m high, with a 200 mm internal diameter. The column is instrumented with up to ten of each of moisture, suction, salinity and temperature sensors, together with a data logger, designed and manufactured at The University of Queensland (UQ) in Brisbane, Australia. The sensors were installed through the wall of the column at various depth intervals, with each set of sensors located at quarter points around the circumference of the column. Two pressure transducers were installed in the column to monitor the change of water level due to rainfall and evaporation. The column was filled with compacted red mud to a depth of 600 mm overlain by 600 mm of cover material, both sourced from the Queensland Alumina Limited (QAL) site in Gladstone, Queensland, Australia. The column is installed on a building roof at UQ, alongside a weather station, and will be subjected to the prevailing weather conditions for up to 1 year in the first instance, during which time the weather conditions and sensor responses will be continuously monitored. This paper reports on the instrumented column set-up and the early results obtained from the test.CITATION:Zhang, C, Williams, D J, Lei, X, Zhu, Y and O’Neill, M, 2018. Instrumented column testing of salt uptake from compacted red mud into a cover, in Proceedings Mine Waste and Tailings Stewardship Conference 2018, pp 220–226 (The Australasian Institute of Mining and Metallurgy: Melbourne).

Jul 23, 2018

By A. M. S. Hussein, B. E. Rogers

Progressively more stringent emission limits and advances in regulations and enforcement have made air compliance more difficult for metallurgical facilities. This has historically required improved collection and treatment of stack sources. Fugitive emission reductions are now increasingly required to achieve compliance. Typically small in magnitude, fugitive emissions have a disproportionate impact on ground level concentrations, can be visible to the public and can influence workplace health and safety. Moreover, these emissions are complex, as they are spread over multiple sources, distance and time and are affected by various activities and conditions. As such it is difficult to find, define and monitor these emissions and their impacts. This difficulty translates to the design of emission reduction measures and operational requirements. This paper presents an overview or ‘heuristic’ of fugitive emissions management for compliance in existing operations. This includes aspects such as the impact of regulations on project scope, approaches to developing a comprehensive emission inventory, considerations for solution development and the plant’s role in sustaining compliance once achieved. Case studies are presented to demonstrate how portions of this approach have been applied.

Jan 1, 2015

As fulfillment of the requirements of Contract H0387019 for the United States Department of the Interior, Bureau of Mines, a complete field kit, for performing on-site determinations of individual employee Time Weighted Average (TWA) exposures to nitrogen dioxide (NO2) and nitric oxide (NO), has been developed by MDA Scientific, Inc. This report provides background information and experimental data validating the use of this kit with confidence to ? 10 percent accuracy.

Jan 1, 1981

By Kazuyuki Kikuta

MMAJ, a govemmental organization in Japan, has carried out a 4 year project for the development of the decontamination and metals recovering technology for the fly ashes from municipal waste incineration. Heavy metals (zinc, lead and copper) are recovered as raw materials for the non-ferrous metals production, without formation of any waste materials to be disposed. More than 500 thousands tonnes a year of fly ashes generation from the municipal waste incineration has been one of the main social issues in Japan, because most of them need to be disposed to the registered areas after decontamination, and occupy 5% of the municipal wastes disposed. The segregation, flotation and chemical process are applied to the treatment of the primary fly ash from municipal waste incineration, and MF (Mitsui-type blast furnace) Process after the chlorine removal to the secondary fly ash. The main results of experiments are -About 90% of heavy metals, zinc, lead and copper, can be recovered from the primary and the secondary fly ashes to the products for the non-ferrous metals production. -Both of the leaching residue from the primary fly ash treatment and the slag from the secondary fly ash treatment can be used as a raw material for the cement production, meaning that the decontamination technology for the ashes without the landfill has been established. -Dioxins in the primary ash can be decomposed satisfactorily, and the dioxins content in the segregation furnace gas is less than O.lng-TEQ/Nm3 without any gas cleaning system

Jan 1, 2003

By Derrick Hunter, Pat Feighan, Keith Chrystall, David Wells

"Equipment which may be remotely operated, has some degree of on-board intelligence, and which for periods of time may operate autonomously, is referred to as telerobotic. Recent advances in electronics, computers and hydraulic equipment have dramatically reduced the cost and simplified the process of converting standard industrial equipment to telerobotic control. The benefits of telerobotic equipment include improved safety by removing the operator from dangerous situations, reduced maintenance costs and increased productivity. This technology has been proven in various military, nuclear, and police applications.The surface mining industry has expressed an interest in automation and is characterized by a willingness to use remotely operated equipment, however, the majority of telerobotic equipment currently in use is experimental or prototypical. Potential applications of telerobotic equipment for surface mining include remote operation of equipment near dangerous high walls and other unsafe areas, utilization of robotic trucks for routine hauling operations, and control of jointed equipment. In addition, component technologies of telerobotic systems are relevant to various forms of condition monitoring, operator feedback systems, and vehicle positioning.Attention must now be directed toward resolving more complex problems associated with enhancing feedback to the operator, improving the man/machine interface, and ultimately, improving efficiency. Removal of the human operator from the work site introduces significant complications in replacing the sensory inputs that an operator normally uses to efficiently run his machinery. These can be difficult to define and even more difficult to replicate remotely and may include restrictions pertaining to vision, hearing, and touch.In cooperation with Defence Research Establishment Suffield and the Alberta Research Council, Robotech Industries Ltd. is pursuing the development of additional technologies to further enhance an operator’s ability to control remote telerobotic equipment. These developments include a head-mounted display, additional control station displays and improvements to coordinated motion control software. Prototypes of these developments are expected to be completed and tested by the fourth quarter of 1997."

Jan 1, 1996

By Sanjeev Malhotra

"This paper presents the results of a pile installation monitoring and performance assessment program for pile foundations supporting 14 piers and 2 abutments of the 1700-ft long bridge crossing over a river in Baltimore, Maryland. Dynamic measurements were conducted during installation and restrike of 16 test piles, one at each support location. The foundation piles were 30-inch diameter, 0.75 inch thick pipe piles at the piers and 24-inch diameter, 0.5 inch thick at the abutments. The piles at the piers were approximately 100 ft long and were designed to carry 260 kips service load with a factor of safety of 2.25. The piles were driven open ended into a variable site stratigraphy containing recent deposits of organic clayey silts near the mudline followed by loose to medium dense sand, with some silt, and then by soil deposits from the Cretaceous period consisting primarily of dense to very dense, poorly to well graded sands and gravels and cobbles, with occasional seams of very hard to very stiff, low to moderate plasticity silts and clays. This paper presents the approach taken to evaluate the driven index piles and to develop criteria for driving production piles. It provides the Engineer with some data on pile driveability in Cretaceous soils in the Baltimore area, soil set-up effect, and an estimate of pile capacity.INTRODUCTIONThe typical approach to pile foundation design and construction should include an indicator pile program with dynamic measurements and a static load test program. However very often paucity of funds and schedule constraints cause an owner to do away with conventional static load testing which can take $25,000 to $100,000 and several weeks per test. This paper examines an alternate (though not equivalent) truncated approach to foundation assessment and presents a case history where this approach was implemented.Dynamic measurements were conducted during pile installation for the 14 piers and 2 abutments of the new 1700-ft long bridge over a river in Baltimore, Maryland. Strain transducers and accelerometers were attached to the pile top during initial driving and restrike of 16 pipe piles. The foundation piles consisted of 30-inch outside diameter, 0.75-inch thick pipe piles at the piers and 24-inch outside diameter, 0.5 inch thick at the abutments. The piles were driven open ended into a variable site stratigraphy. The approach taken to assess the foundation performance included 1) a pre-field wave equation driveability analyses, 2) field pile driving measurements, 3) post-field Case Pile Wave Equation Analyses (CAPWAP), and, 4) revised wave equation analyses based on field and CAPWAP data. The following sections describe in greater detail each of the steps taken to assess foundation performance and the results obtained."

Jan 1, 2005

By Gervais Soucy, François Quesnel, Pierre Hovington, Wen Zhu, Karim Zaghib, Jocelyn Veilleux

The properties of lithium titanates anodes in Li-ion batteries are highly dependent on their secondary constituents. While their main phase is usually constituted of Li4Ti5O12, significant quantity of lithium titanates compounds of various stoichiometry are often present, due to either the processing, usage or aging of the material. These may go underreported, as many of these spectrums overlap or display low signal in X-ray diffraction (XRD). Samples of nanosized lithium titanates synthetized by inductive plasma were characterized by XRD and scanning electron microscopy (SEM), as they provide a regular yet typical crystallite size and shape including multiple phases. A Rietveld refinement was developed to extract the composition of these samples. Mass balance through further annealing and differential scanning calorimetry (DSC) enthalpy measurements from phase transformations were also used as identification and validation techniques.

Jan 1, 2015

By Jie Ma, Bo Wang, Jieyu Zhang, Jian Zhao, Zheng Chen

"In this paper, solidification process of steel ingot was simulated by ProCAST software, based on cellular automaton-finite element (CAFE) model. A 22 t steel ingot was divided into continuous small zones (100x150x180 mm) in radial direction, then the temperature field, shrinkage cavity and porosity, particularly, the microstructure were simulated. The results show that: there was a columnar-to-equiaxed transition in microstructure on radial direction. Zones, closing to the center of the ingot, had a more developed and fined equiaxed zone, while zones closing to the periphery of the ingot had a more developed columnar zone. It indicated that temperature gradient has a great influence on microstructural morphology. Thus, the simulation results were highly agree with the experimental results, verifying the feasibility of this simulation method. It significantly reduces the time of simulation, and has important significance for predicting the microstructure of large steel ingot.IntroductionSolidification microstructure of steel ingot have a significant effect on the quality of the final steel products. Although many experimental works have been carried out in order to obtain the optimum condition for solidification process of continuous casting, it is also very desirable to establish mathematical models to simulate the evolution of solidification structure. The simulation methods can be divided into deterministic models and stochastic models, which have been developed rapidly over the last couple of decades. Cellular automaton method is one of the stochastic models. Rappaz and Gandin [1, 2], Nasatac and Stefanescu [3, 4] are the earliest researchers engaged in the this field. Moreover, Rappaz and Gandin simulated the solidification structure and CET (columnar grain to equiaxed grain transition) of metals using the CAFE method (cellular automaton-finite element method) for the first time [1, 2]. Recently, the CA (cellular automaton) model also considered the effects of fluid flow on the solidification process. Zhu, et al. [5-11] improved method of CA , they used the KGT model to describe the undercooling needed during the growth of the dendrite tip."

Jan 1, 2014

By W. J. Mahoney

A good quality assurance program at a coal mine or power plant is accurate, timely, and consistent. The quality analysis is accurate due to a complete sampling of the coal stream loaded into the unit train. The sample analysis is accurate because standardized testing procedures are applied. Once the analysis is completed, the results must be communicated to the electric utility in a timely manner. The electric utility needs the results to better manage the coal inventory at the power plants. A quality assurance program can also help the mine deliver a consistent product to the electric utility's power plants. The importance of the three major tenants for a good quality assurance program: accuracy, timeliness and consistency, are based on major changes that are taking place in the electric utility industry.

Jan 1, 1994

By G. L. Oldright

This paper is the second of a series that is to appear on smelting in the lead blast furnace. The objects of this investigation are to determine the conditions obtaining within the blast furnace by direct experimentation, and to correlate the behavior of the furnace at various times with the main factors governing the operation of the blast furnace, and metallurgical losses. The writers wish to express their appreciation to the management of the International Smelting Company at Tooele. Utah, for their kind cooperation which made possible the assembling of these data.

Jan 1, 1929

By Stavros A. Argyropoulos

Exothermic mass transfer takes place in various areas involving metallic systems, ranging from liquid metal processing operations to the growth of thin films in microelectronics. The formation of intermetallic compounds plays an important role in the exothermic mass transfer of metallic systems. Two types of exothermicity are identified , namely , Microexothermicity and Macroexothermicity. The former is encountered when small amounts of metals are mixed, while the latter is exhibited when a solid metal in a lump form is added into liquid metal. In this paper two types of exothermic mass transfer in metallic systems will be presented and reviewed. Mathematical modelling work for these types of exothermic mass transfer will be analyzed.

Jan 1, 1993

By V. F. Parry, W. S. Landers

"INTRODUCTION The primary object of this investigation was to determine changes in physical and chemical properties of subbituminous lump coal while in storage for 8 months in a typical residence and to demonstrate how this fuel may be stored without degradation or spontaneous combustion. The second object of the study was to determine how the stored coal performed in a hand-fired furnace operated under practical conditions.The investigation revealed that if care is exercised in placing sub-bituminous lump coal in a closed bin, no significant slacking or degrada¬tion occurs, no hazards arise, and over-all indicated efficiencies of about 65 to 69 percent can be obtained under practical,firing conditions that the average home owner can meet.Owing to the war emergency, much attention is being given to the proper storage of coal, and campaigns are being conducted to increase the quantity of coal being stored to relieve transportation and production overloads. Ordinarily, coal dealers do not recommend storage of subbituminous coal in homes owing to deterioration of the coal and to possible hazards from spontaneous combustion. This practice has grown from some troubles that have been experienced, which can be traced to improper preparation, improper bins, and poor technique in placing coal in a bin. There is no good reason why subbiturninous lump coal cannot be stored safely in homes."

Jun 1, 1944

By G. Frithum

In the present paper a new and highly economic route for Fe-separation from HCl leaching processes in hydrometallurgical applications is described. In most ore leaching processes, Fe is involved and needs to be separated; HCl has become an interesting leaching agent, because it can be recycled. Usually a mix of Fe2+ and Fe3+ is obtained which can be hydrolyzed directly (in case only Fe3+) or roasted via pyrohydrolysis (in case of Fe2+) to ferric oxide. Economic oxidation of Fe2+ to Fe3+ is described, and potential technologies for regeneration of HCl with separation of Fe are shown and compared.

Jan 1, 2014

By I. Demers, A. Blier, M. Mbonimpa, M. Benzaazoua, B. Bussière

The Doyon Mine in Quebec, Canada, evaluates the possibility of desulfurizing its tailings to produce material to be used as cover for the acid-generating tailings disposal site. Laboratory tests showed that a single-layer cover made of desulfurized tailings placed over reactive tailings can prevent the generation of acid mine drainage. Modeling with the software Vadose/W was used to optimize the design parameters, namely, cover thickness, water table position and residual sulfide content of desulfurized tailings following laboratory work. It was found that the optimal configuration includes a 1-m (3.3-ft) desulfurized tailings cover containing 0.8% S, with the water table kept at the interface between the reactive tailings and the cover. To maintain the cover performance to reduce oxygen flux toward acid-generating tailings even in the event of a long dry period, a sand layer is suggested to protect the cover from excessive evaporation. It is possible to reach the environmental objective for oxygen flux chosen for the Doyon Mine (10 mol/ m2/year) with the protective sand layer, even in extremely dry conditions.

Jan 1, 2009

By H. E. Perlee

The concentration limits of flammability and autoignition temperatures of trichloroethylene in atmospheres of air, oxygen, and nitrogen tetroxide have been determined in a spherical vessel. The autoignition temperatures of TCE in atmospheres of air, oxygen, and nitrogen tetroxide were found to be 419°, 396°, and 221° C, respectively. The flammability zones of TCE-air, TCE-oxygen and TCE-nitrogen tetroxide mixtures at 100° C were found to be 10.5 to 41, 7.5 to 91, and 13.5 to 69 volume percent TCE, respectively. In addition, maxi-mum combustion pressures of 50 ps and 140 were recorded for constant volume combustion of the lower limit mixtures of trichloroethylene in air and oxygen, respectively.

Jan 1, 1966