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By H. F. Ghezzi

The indirect method of drying coal fines is applied to filter cakes which ordinarily contain 22 to 30% moisture and are not readily transportable. The "Thermal Dryer", which operates on the mass transfer principle, has found wide use in coal preparation plants. The thermal dryer is penalized in operation by the necessity of adding coarse coal to the wet fines before entering the dryer body in order to produce a permeable bed, and thus enable hot gases to uniformly contact the wet mass. The ratio of coarse coal to fines varies from 2:1 to as much as 4:1, depending on the average particle size, moisture, and ash content of the fines.

Jan 1, 1985

By Christian M. Sagedahl

The stringent environmental regulations for air pollution regarding emission control, along with the need of dry concentrates to feed autogenous smelting processes, are enhancing the development of cleaner technologies. Indirect drying of concentrates by a Kvaemer steam dryer is a technology with promising results, reducing dust entrainment to the exhaust gas stream and leading to smaller dust separation units. The Kvaemer dryers are designed for a very high availability, a high-energy efficiency, low amount and velocity of exhaust gases, no SO2, CO or CO, emissions combined with a wide range of satisfactory operating conditions and low total operational costs.

Jan 1, 1999

By J. de Bakker

It hardly needs to be repeated that if coal is to continue as America’s premier source of cheap energy, it is absolutely necessary that the carbon dioxide from its combustion somehow be sequestered. A promising method proposed to accomplish this is the “indirect” carbonation of serpentine in a concentrated magnesium chloride brine. Indirect carbonation could be also applied to precipitate magnesium in lateritic nickel processing: this would not only solve magnesium-control problems in laterite hydrometallurgy, but also reduce its energy requirements and create CO2-sequestration credits. Fifty-five percent of the electricity generated in the United States comes from coal-fired power plants, and American coal reserves can last over 500 years at 1990-level consumption1. Coal is therefore both abundant and cheap: it could (and in fact probably will) continue to be an affordable source of energy, both for producing electricity and as a feedstock for liquid hydrocarbon production by Fischer-Tropsch reactions. As a result, it is important to find a workable method of permanently sequestering CO2.

Jan 1, 2007

By A. Dell’Era, E. Ciro, C. Lupi

The indium recovery via electrowinning from sulfate baths has recently gained significant attention as it does not present toxic emissions, hermetically sealed system requirements, human health, and environmental hazards. Following previous works related to the optimization process for AISI 316L and Ni cathode, it was observed significant importance of the metal supports on the input and output parameters of the indium electrowinning process from sulfate solutions. Thus, comparing input and output parameters in both cases seems very interesting. Particularly, regarding the input parameters, the attention has been focused on the electrolyte composition, current density, and temperature, while productivity, morphology, and structure have been considered regarding the output parameters. Considering the productivity as the optimal output, the findings for Ni cathode were better than that for AISI 316L in most of the selected conditions studied. In the case of morphology, indium grains appear rounded and dendritic on the AISI 316L, while those on the Ni cathode show stratified lamellar grains. Anyway, the indium deposit obtained on Ni cathode shows bigger grains independently from the used operative conditions with respect to that on AISI 316L. Regarding the structure, it is clearly tetragonal, but preferential orientation, crystallinity, and deformation of the structure strongly depend on the metal support.

Jun 14, 2023

By Priscilla Aki Mori de Hanashiro, Viviane Tavares de Moraes, Denise Crocce Romano Espinosa, Hugo Hashimoto

"The LCDs are used in televisions, calculators, mobile phones, computers (laptops and tablets), video games and other electronic devices. The advancements in technology make obsolete these devices, causing excessive disposal of LCDs and therefore decreasing life span of landfills. In this context, the LCDs from LED LCD TVs arise as an additional source of waste electrical and electronic equipment (WEEE). Thus, it is essential to develop LCDs recycling methods, beginning with the LCD characterization followed by displays processing, aiming the materials separation and using some Ore Treatment Techniques, and finally, the recovery of indium using acid leaching. The analysis methods that will be used in this work are: Fourier Transform Infrared (FT-IR) and Inductively Coupled Plasma Optical Emission Spectrometry (ICP-OES).IntroductionLiquid Crystal Display (LCD) technology is applied in modem televisions, calculators, mobile phones, computers and a wide range of electronic devices. It has replaced Cathode Ray Tube (CRT) technology as the most advantageous display product, due to lower electrical power consumption, size and weight reduction, and no radiation emission [ 1]. The constant improving of LCD screen technology reflects on its growing contribution to the amount of waste electrical and electronic equipment (WEEE): an estimated 50 million tons of WEEE are produced every year [2]. Once the most common method of its disposal are landfills, the LCD technology therefore became an environment issue [3].LCD structure is composed by components made by different materials. In order to develop a LCD recycling methodology that gives the right destination to these materials, a previous characterization stage is required. This characterization includes a disassembly process and material identification analysis. One of the LCD components is the screen, which is composed by polymeric and glass layers. The liquid crystal glass was the starting material of this study. It contains indium in the form of indium tin oxide (ITO) film. This ITO film is deposited in the glass by a sputtering process and acts as the electrode material [4,5]. It has in its composition 90% ofln203 and 10% ofSn02 [6]."

Jan 1, 2014

By C. F. Smart

SINCE their comparatively recent development, the alloys of cadmium with silver and copper or nickel, and of cadmium with nickel alone, have been used somewhat extensively as liners for connecting rod bearings and main bearings of internal-combustion engines. In applications where, owing to high hearing loads and elevated operating temperatures, the life of hearings made from tin-hale or lead-base alloys has been undesirably short, cadmium alloys have demonstrated considerable advantage. In applications where, because of deflection of the crankshaft or bearing supports, copper-lead bearing metals have resulted in scored shafts, cadmium alloys have been operated successfully. The somewhat serious drawback to these alloys in hearing service has been that they, in common with copper-lead and certain lead alloys, are susceptible to corrosion in the presence of lubricants containing organic acids. These acids may be fatty acids (such as oleic acid) derived from animal or vegetable oils that sometimes have been compounded with engine lubricants, or they may be compounds of an acid nature developed by the oxidation of some petroleum oils under operating conditions. The result of such acid attack on hearings is illustrated by the photograph, Fig. 1. The petroleum oils that are most readily oxidized to a corrosive condition, and the operating conditions under which such oxidation most readily occurs, are now rather well known among the technical organizations of both the petroleum and automotive industries. While means have been developed for inhibiting petroleum oils against such acid formation, the knowledge that this condition may be encountered has been a factor in restricting the wider use of cadmium alloys as engine bearings. It has appeared, therefore, that their value and use would be enhanced if they could be made corrosion-resistant to a degree compatible with the most severe operating requirements. Investigation, undertaken with this in view, indicated that the addition of fractional percentages of the metal indium to the cadmium bearing

Jan 1, 1938

By C. F. Smart

SINCE their comparatively recent development, the alloys of cadmium with silver and copper or nickel, and of cadmium with nickel alone, have been used somewhat extensively as liners for connecting rod bearings and main bearings of internal-combustion engines. In applications where, owing to high bearing loads and elevated operating temperatures, the life of bearings made from tin-base or lead-base alloys has been undesirably short, cadmium alloys have demonstrated considerable advantage. In applications where, because of deflection of the crankshaft or bearing supports, copper-lead bearing metals have resulted in scored shafts, cadmium alloys have been operated successfully. The somewhat serious drawback to these alloys in bearing service has been that they, in common with copper-lead and certain lead alloys, are susceptible to corrosion in the presence of lubricants containing organic acids. These acids may be fatty acids (such as oleic acid) derived from animal or vegetable oils that sometimes have been compounded with engine lubricants, or they may be compounds of an acid nature developed by the oxidation of some petroleum oils under operating conditions. The result of such acid attack on bearings is illustrated by the photograph, Fig. 1. The petroleum oils that are most readily oxidized to a corrosive condi-tion, and the operating conditions under which such oxidation most readily occurs, are now rather well known among the technical organiza-tions of both the petroleum and automotive industries. While means have been developed for inhibiting petroleum oils against such acid formation, the knowledge that this condition may be encountered has been a factor in restricting the wider use of cadmium alloys as engine bearings. It has appeared, therefore, that their value and use would be enhanced if they could be made corrosion-resistant to a degree compatible with the most severe operating requirements.

Jan 1, 1938

By J. A. Finch

A closed grinding circuit, typified by a ball mill-cyclone combination, is often required to treat a feed comprised of a variety of minerals of differing properties. Usually, the individual behaviour of the minerals is not assessed, a procedure which requires sizing and metal or mineralogical assaying of each size fraction. Further, sizing is frequently by screening to perhaps 325 mesh meaning that detail on the important -44 um fraction is unavailable. It is well appreciated that minerals can exhibit both individual classifying and grinding behaviour. Recognizing that cyclone classification results from differential centrifugal settling and acceleration rates, then minerals of differing specific gravity will exhibit individual mineral cyclone performance curves. If the minerals have differing grindabilities, then individual mineral rates of breakage may be expected. When treating an ore containing minerals of a range in specific gravity and/or grindability, individual mineral behaviour in the closed-circuit grind could be notable and perhaps important to the overall concentrator performance. An example is a lead-zinc ore, as shown by Kelsall et al.(1,2) This paper describes the individual mineral cyclone performance curves at sizes down to ti 10 um for the four major minerals at two lead-zinc concentrators; the Sullivan concentrator at Kimberley, British Columbia, and the Pine Point Mines concentrator at Pine Point, North West Territories, both operated by Cominco Ltd. In addition, individual mineral grinding behaviour for the four major minerals at the Sullivan concentrator is presented.

Jan 1, 1977

By J. A. Finch

Individual mineral cyclone performance curves were determined for the four major minerals at two lead-zinc concentrators. Sizing was by screen and cyclosizer down to approximately 10 um, with lead , zinc and iron as saying of each size fraction. The performance curves were similar in shape and located according to the mineral specific gravity, Pm. The curves displayed a discontinuity at the fine end and a magnitude of short-circuiting of fines to the underflow which increased with Pm. Mass fraction of water to the underflow was only a guide to this short-circuiting. Sharpness of separation seemed in dependent of Pm. An inflection in the over-all performance curve was shown to be a consequence of the individual component mineral performance. A general relationship was observed showing that the flow regime of classification changed from laminar/ intermediate to turbulent with increasing cyclone feed size. Individual mineral size reduction for the four major minerals at one of the concentrators was also determined. Size reduction of the silica was greater than that of the galena, in contradiction to their accepted relative grind-ability. The observation did correlate with silica being much coarser than the galena in the feed to the ball mill. It is suggested that the silica acted as a buffer to the galena.

Jan 1, 1977

By Kiichiro Hayashi

"Indonesia is one of the world leaders in palm oil production. Palm oil industry is an industry to be considered when it comes to environmental impacts. This paper utilizes three step approaches. First, a material flow analysis of palm oil related industry was conducted in Indonesia. Second, a factory visit survey was conducted for getting information on environmental impacts of plantation and CPO mills. Third, a LCA study was made for a model Indonesian CPO mill in several bio-waste treatment options. Main findings were that, first; over 70% of FFB was bio-wastes generated from CPO mills. Second, some mills introduced a zero emission bio-waste policy. However, untreated bio-wastes in the zero emission policy, such as, CH4 from POME ponds, may have potential to reduce more impacts on the environment. Introduction Indonesia is one of the world leaders in palm oil production with approximately 12.4 million tons of crude palm oil (CPO) production in 2005 and with the plantation area 5.6 million ha spreading out in 19 provinces [10]. The expansion of palm oil cultivation in Indonesia and its export oriented industry heavily relies on the strong world market demand for food. Currently, there are 320 CPO industries in Indonesia [10]. These include plantations and palm oil related factories. Among them, there are six biggest players in CPO business in Indonesia: PT. Perkebunan Nusantara (PTPN) consisting of 9 PTPN, Sinar Mas, Raja Garuda Mas, Astra Agro Lestari, Minamas Plantation and Indofood. They are managing more than 50% of plantation estate in Indonesia and are leading the Indonesian palm oil business.Palm oil industry is an industry to be considered when it comes to environmental impacts. Unfortunately, there is not so much available information related to the performance of each CPO on environmental impacts. There are reports which provide information on environmental impacts of CPO mills in South East Asian countries, but are limited to, for instance, Thailand’s cases [4 and 5] and Malaysia’s cases [1, 3, 6, 7, 9, 11 and 12]. On the other hand, similar studies on the Indonesian’s case are not well established in academic literatures. And also there is limitation on Indonesian palm oil industrial information from plantation to consumption and disposal in academic articles. There is no literature related to material flow analysis focusing on the whole Indonesian palm oil related industry. One way to describe and present the environmental impacts is through a life cycle assessment (LCA). The LCA could be used to estimate the impacts of CPO production including the stages of plantation, transportation and milling [5, 8 and 11]. However, studies on Indonesian CPO production process were not well established in academic articles. The purpose of this paper is thus to clarify environmental impacts of palm oil industry in Indonesia especially by focusing on plantation and CPO mills with consideration to various bio-waste treatments."

Jan 1, 2008

By A. Motamedi

Indoor localization has gained importance as it has the potential to improve various processes related to the lifecycle management of facilities and to deliver personalized and location-based services. Radio Frequency Identification (RFID) based systems, on the other hand, have been widely used in different applications in construction and maintenance. This paper investigates the usage of RFID technology for indoor localization of RFID equipped movable assets during the operation phase of facilities. The location-related data on RFID tags attached to fixed assets are extracted from a Building Information Model (BIM) and can provide context-aware information inside the building which can improve Facilities Management (FM) processes. The paper proposes a new approach to use received signals from available reference tags in the building attached to fixed assets to locate movable assets. The approach uses signal pattern matching and clustering algorithms for localization. As a result, a user equipped with an RFID reader is able to estimate the location of target assets, without having access to any Real- Time Location System (RTLS) infrastructure. A case study is performed to demonstrate the feasibility of proposed methods.

Aug 1, 2013

By Antrekowitsch Jürgen

The recycling of residues from metal producing by-products has become a main field of interest in metallurgical investigations. Forced by a stricter environmental legislation and the resulting increase of landfilling costs, combined with the aim to recover as many valuable metals as possible, a lot of different processes have been developed in the last two decades. Because of the high yearly tonnage residues from the iron and steel industry like slags, dusts and sludges have moved in the center of interest. Dusts from the steel mill, containing heavy metal oxides and halides did not play a considerable role as secondary raw materials for a long time. They even contain a huge amount of leachable elements and compounds which cause noticeable problems in case of a dumping. Nevertheless, the implementation of a new landfilling regulation, including a prohibition of aboveground dumping without inertisation, caused a rising interest concerning recycling technologies for such residues. In addition, the zinc content of these dusts became higher and higher and began to play the most important role for the economy of dust recycling.

Jan 1, 2006

By R. D. Stewart

Abstract. Induced fluorescent sorting is a means of beneficiating an ore by selective labeling with a reagent combination which fluoresces when activated by ultraviolet light The reagent combination normally consists of a surface active compound and a fluorescent dye. The surfactant adheres selectively to a specific surface and carries the dye with it. Upon activation with ultraviolet light, the labeled pieces, in the size range 1.27 cm to 20 cm (0.5 to 8 in.), are detected during free fall by photosensitive cells and ejected by water jets. Either ore or gangue may be labeled.

Jan 1, 1980

By H. O. Seigel

Induced Polarization includes many types of dipolar charge distributions set up by the passage of current through consolidated or unconsolidated rocks. Among its causes are concentration polarization and electrokinetic effects in all rocks and the phenomenon of Overvoltage in rocks containing electronic conductors such as metallic sulphides and graphite. In normal rocks the polarization effects may be usually con-fined within relatively narrow limits and any large departures may be at-tributable to the presence of electronic conductors. In practice, Induced Polarization is measured in one of two ways. In the first a steady current of some seconds duration is passed and abruptly interrupted and the slowly decaying transient voltages existing in the ~round are measured after interruption. This is known as the "pulse", "transient", or Direct Cur-rent Induced Polarization (D.C.I.P.).The second method entails a comparison of apparent resistivities using sinusoidal alternating current of two or more frequencies, generally within the range of 1/10 to 10 c.p.s. Induced Polarization extends the

Jan 1, 1962

By Richard W. Cannon

INTRODUCTION The authors, by means of this paper, will attempt to show the role of Induced Polarization and Resistivity surveys in the discovery of the orebodies of Gibraltar Mines Limited (N.P.L.). In this paper, we will also attempt to show the importance of conducting large enough surveys in order to properly evaluate the results obtained from these surveys. LOCATION The orebodies of Gibraltar Mines Limited (N.P.L.) are located on the western slope of Granite Mountain, central British Columbia (52°30' north, 122°16' west) (See Fig. 1). The property lies approximately 28 miles north of Williams Lake, B.C. and can be reached by way of 10 miles of newly improved road from McLeese Lake, on the Cariboo Highway. The area in and around Gibraltar Mines has a moderate topographic relief with elevations between 3,500 and 4,100 feet. {EARLY HISTORY AND GEOLOGY The present Gibraltar Mines property before amalgamation consisted of the Pollyanna property (Duval-Canex) and the Gibraltar property (original Gibraltar Mines) as well as some Coast Silver and McLeese Lake Copper claims (See Fig. 2). The Pollyanna property was first described in the 1917 B.C. Minister of Mines Report which referred to it as the "Rainbow Group". The development at that time consisted of several open-cuts on copper bearing quartz veins.

Jan 1, 1972

By D. M. Hendrick, D. K. Fountain

Since the discovery by conventional prospecting of the Horne deposit in 1920, the Noranda area has produced 82 million tons of copper-zinc-gold-silver ore from sixteen massive sulphide bodies. Recent exploration in the area has consisted of systematic studies employing geology, geophysics and geochemistry. Due to the depth of the deposits being sought, surface geo-physical surveys are limited in their effectiveness as DIRECT indicators. However, because of the geological environment, surface geophysical methods, and the Induced Polarization method in particular, can be success-fully employed as INDIRECT indicators of ore deposits. Examples of survey results from various properties in the Noranda area illustrate the advantages and limitations of the Induced Polarization method as an exploration tool in this area.

Jan 1, 1971

The National Mining Hall of Fame and Museum in Leadville, CO seized the opportunity to show off during its 10th anniversary induction banquet on Sept. 6. "We wanted to make people more aware of the mining hall of fame and museum," said Carl Miller, its executive director. The annual event honors inductees into the Mining Hall of Fame. This year, the inductees included Paul Wheeler Allen, Joseph Rosenblatt, Arthur Fay Taggart, Joseph Toy, Joseph Wharton and John Benjamin Zadra (ME, August, pp. 60-63). Allen, of Pasadena, CA and Rosenblatt, of Salt Lake City, are both living. Only Allen was able to attend. This year's induction banquet was the first held in Leadville, North America's highest incorporated city, at 3,094 m (10,152 ft) above sea level. The banquet gave attendees an opportunity to see the museum in its century-old 6,500-m2 (70,000-sq ft) Victorian schoolhouse. Many of the 350 guests came in 1890s dress to the black-tie affair. The evening included a cocktail reception and an open house along with a catered, prime rib dinner. During the open house, attendees had the opportunity to tour the museum's 12 rooms of exhibits and displays. Among items of interest, it was noted that a framed directory of inductees now enhances the entrance to the hall of fame. The directory is organized by the inductees' names and the location of their plaques, allowing visitors to quickly find hall of fame members. Noted mining historian and author Duane Smith delivered the keynote address at the banquet. After the induction of the six honorees, attendees danced to the big-band era music of the Leadville 17-piece band BandAge. Karl Elers was the master ceremonies for the evening's program. He is a member of the hall of fame's board of directors and is chairman of Battle Mountain Gold Co. Allen was honored by the presence of 26 former colleagues and associates. He told the audience that he originally thought the museum should have been located in Denver. "But I have been proven wrong," he said. For many years, Allen was the operational executive of Cyprus Mines Corp. and a key participant in the company's growth. Allen received a replica of his mining hall of fame plaque from Thomas Falkie, chairman of the hall of fame's board of governors and president of Berwind Natural Resources Co.

Jan 1, 1997

By John H. Hearding

Induction heating, together with automatically controlled tempering and hardening is giving Oliver faster and more accurate bit sharpening, while experiments with bit taper promise to offer increased footage per bit.

Jan 10, 1953

By C. Lemire, A. Biscaro

Ferro-alloys are sold according to the size grading specifications of users. Fines are produced during crushing and the amount produced depends on the crushing process and the physical characteristics of the ferro-alloy. The market value of fines has declined. Market demand is very weak and in some extreme cases is nonexistent. An induction furnace melt process has been developed to solve this problem. The process feasibility has been demonstrated on a small scale with charges of approximately 2.5 kg. The piloting was carried out using a 100 kW furnace with a metal liquid capacity of 140 kg. The operating parameters were determined during the pilot process. The procedures were defined and the equipment required for melting fines produced at the client's site was sized. With the production of ingots, the client can now recover the full value of ferro-alloy fines.

Jan 1, 2004

By Fei Chen, Lesley J. Gaydos, Laurence M. Demers, Douglas C. Kuhn

The fibrogenic effects of silica in experimental animals and humans has been extensively studied (I 7, 20). However, the pathogenesis and molecular mechanisms underlying lung injury and fibrosis resulting from silica exposure remain to be elucidated. It is well-documented that silica can stimulate monocyte-macrophage lineage cells to produce cytokines and growth factors, including interleukin-I (IL- I) (20), tumor necrosis factor-ex (TNF-cx) (I 7), insulin-like growth factor-I (IGF-1) (4), and transforming growth factor-P (TGF-P) (24). Consequently, it has been suggested that the fibrogenic effect of silica may be mediated by cytokines in the fater stages of silicosis. During the early phase of interaction between silica and the pulmonary alveolar macrophage, several direct and indirect lines of evidence suggest that reactive oxygen intermediates (ROI) may play a pivotal role in silica- induced tissue damage (2I, 22). One of the most important components of and contributors to ROI is nitric oxide (NO) produced from L-arginine and molecular oxygen under the catalytic influence of NO synthase (NOS) (I 9). At present, at least three NOS genes have been cloned: a constitutive neuron NOS, a constitutive endothelial cell NOS and an inducible NOS (iNOS) (16). A number of factors have been shown to differentially induce iNOS gene expression in different cell lines including bacterial cell products and foreign antigens. During inflammation, NO is a double-edged sword in terms of the host immune defense mechanisms and the physiologic response to an inflammatory insult. The macrophage is one of the major cellular sources of NO. During the early phase of acute inflammation, NO produced from the macrophage appears to facilitate the clearance of pathogens and promotes a local relaxation effect on the microcirculation of vascular smooth muscle. When the production of NO is left unattenuated, especially under oxidative stress, direct cytotoxic effects of NO can emerge through the formation of peroxynitrite as a result of a reaction between NO and superoxide (2).

Jan 1, 1998