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By Tae-kyeong Yeu

KIOST has developed the pilot mining robot, named MineRo ?? from early-2011 to mid- 2012. The robot consists of two unit-modules having an identical mechanical structure and hydraulic system. One unit-module has two track systems, two pick-up devices, two crushers, one lifting pump and one thruster. The pick-up device is fitted on the frame of the track device. All actuators are driven hydraulically, which are manipulated by valves and the controllers. Each unit-module is equipped with one dual HPU of 250kW / 4,000V. PWM-16 (INNOVA AS) as hydraulic valve controller is adopted, which outputs PWM signals of 16 channels and can be used under pressure in oil-filled box. To measure angular velocity or displacement of hydraulic actuator, turbine-type flow-meters are adopted. The flow-meter has RF (Radio Frequency) type pulse detector, which extends the flow range by eliminating drag on the rotor. Two track motors, two crusher motors, lifting pump, one thruster can be controlled their velocities through feedback of the measured flow-rates. As well as the flow-rates, the states of the hydraulic system such as hydraulic pressures, temperatures, leakages are measured through a self-developed flow-pressure canister. In that canister, multi-channel amplifier boards are installed, through which the vast amount of data is acquired and transmitted to the main controller using serial communication.

Sep 14, 2011

Correspondent. Must be able, by virtue of, connection, to forward; daily ands weekly, reports, outlining, conditions affecting economics of. industries, particularly the metallurgical, and chemical, industries. New. York, City. R-1982. Sales Lubrication. Engineer. Preferably with experience, as chief marines engineer familiar with internal-combustion; engines and, with, automobile trade. Must be good salesman, of goody appearance and be able to meet people. Middle West. Salary $27.00: to start. R71984.

Jan 12, 1919

By O. N. Mohanty, S. Mohan Rao, N. D. Rao, T. Mukherjee, P. V. T. Rao

"Chromite ore is an indispensable raw material in the manufacture of ferro-chrome and charge-chrome, which are used for the production of stainless and other alloy steels. The demand for chromite ore is ever increasing because of increasing consumption of these steels. Keeping this in view, Tata Steel is keen to recover values from fines and wastes, and also to produce value added products from their captive chromite mines and its processing plants.Tata Steel has its captive chromite resources at Sukinda, Orissa. They contain two ore types, i.e. (i) Ferruginous and (ii) Siliceous. The generation of off-grade ores is an increasing trend and simultaneously customer quality requirements are becoming ever more stringent. The ferruginous type ore also contains a considerable quantity of in-situ fines (~20% particles below 0.5 mm) that compound the beneficiation problem.In many places, in India and abroad, mined non-marketable off-grade and low grade chromite ores are upgraded by using either simple classification techniques like screw classification, hydrosizing, hydrocycloning or conventional gravity concentration processes such as Heavy media separation, Jigging, Spiraling, Tabling etc.At Tata Steel, the ferruginous type ores are treated in Chrome Ore Beneficiation (COB) Plant that comprises: a crushing and grinding circuit; a classification circuit using hydrocyclones; and a beneficiation circuit using 4 stage spirals in the coarse circuit (-0.5+0.1 mm) and 3 stage spirals & tables in the fine circuit (-0.1+0.038 mm). In this process, 3 types of tailings are being generated and together analyses about 17 % Cr2O3, which is high. From the present operation the chromite recovery is around 70% and could not produce coarse concentrates (+0.5 mm size). Whereas the siliceous type ore is treated in the Lumpy Ore Processing (LOP) plant, consisting of crushing-washing & classification-hand sorting operations, to produce marketable grade lumpy ore and –10 mm de-slimed fines. These fines are intermittently treated in the COB plant. The higher silica content (greater than 1%) and low Cr/Fe ratio (less than 2.8) are the problems with these concentrates."

Jan 1, 2003

By J. W. Rutter, K. T. Aust

The motion of individual grain boundaries under a constant driving force was investi,qated for zone-refined lead, with and without solute tin additions. The rate of boundary migration was found to depend strongly on tin content and on the orientation relationship between the adjacent grains. The results are compared with the theory of impurity-controlled grain boundary miqration developed by Lucke and Detert. Evidence was found that grain boundaries separating grains which have the Kronberg-U&apos;ilson orientation relationships of 38 and 22 deg about <Ill> and 28 deg about <100>, correspond to boundaries of high mobility. The results are discussed in relation to the formation of annealing textures in metals and the structure of high-angle boundaries. It is generally known that small amounts of impurities in solid solution greatly influence the re-crystallization behavior of metals. For example, the addition of 0.005 at. pct of tellurium to copper,&apos; or 0.005 at. pct of silver to lead,2or 0.01 at. pct of manganese or nickel to aluminum3 greatly decreases the rate of recrystallization of these metals. However, this effect may be the combined result of a decrease in the rates of both nucleation and growth; recrystallization experiments do not separate these two factors. Bolling and winegard4 determined the effects of small quantities of tin, silver, and gold on grain growth in polycrystalline zone-refined lead.

Jan 1, 1960

By William Gleason

"Komatsu has been on the cutting edge of autonomous mining for the past 30 years and the company remains at the forefront of the technology that is changing from concept to a full-fledged reality.In 1996, Komatsu America Corp. (KAC) purchased a controlling interest in Modular Mining Systems; a move that enabled both companies to expand their product lines. It was through this effort that Modular helped to deploy the first autonomous haulage system (AHS) — the Komatsu FrontRunner system. In January 2008, the first commercial implementation of the FrontRunner system occurred at Codelco’s copper mine in Chile. Since then, Komatsu has put more than 130 haul trucks into seven sites on three continents to haul copper, iron ore and oil sands and its equipment has moved 1.8 Gt (2 billion st) of material with zero lost time incidents attributed to Komatsu’s autonomous trucks. The 1.8 Gt (2 billion st) is the most of any commercial mining autonomous haulage system and there is more to come. In November, Komatsu announced that an additional 150 autonomous haul trucks will be deployed to the Canadian oil sands over the next seven years.Komatsu has continued to pioneer autonomous haulage development, creating a range of autonomous options that includes semiautonomous and teleremote options all the way up to a haulage vehicle that stole the show at the world’s largest mining equipment trade show.In 2016, Komatsu advanced the concept of driverless haul truck to a new level when it displayed its Innovative Autonomous Haulage Vehicle (IAHV) at MINExpo in Las Vegas, NV. The concept vehicle is the first mega class haul truck designed to be fully autonomous, without an operators’ cab included on the vehicle.Unlike other haul trucks, the vehicle was developed exclusively as an unmanned vehicle designed to maximize the advantages of unmanned operation. Among other advancements, it was designed to distribute equal load to the four wheels, both when the vehicle is loaded and unloaded, and adopt four-wheel drive, retarder and steering. Komatsu said it is aiming for high-performance shuttling of this vehicle in both forward and reverse travel directions, thereby eliminating the need for K-turns at loading and unloading sites."

Dec 1, 2018

By Adolf Mikula

Lead-tin solders are commonly used in electronic packaging due to their unique combination of electrical, chemical, physical, thermal and mechanical properties. Since it is known that lead and lead containing alloys cause great environmental concern and health hazards it is necessary to replace lead in solder materials. Besides the environmental concerns new technologies in electronic packaging require new and improved solders. In most cases the new solders will consist of ternary or quarternary alloy systems, the main component will be tin or indium and the second element could be bismuth, silver, copper and gold and to improve certain properties a third element will be added. For a third element zinc, nickel, antimony and aluminum can be considered. This report will concentrate on solders containing zinc as an environmental safe element.

Jan 1, 2003

By Charles H. Behre

KEYNOTE of the mining geology sessions was the preparation for an extensive war with all that this implies as to the need for strategic minerals, both metallic and nonmetallic. Nevertheless the sessions also included many papers of less urgent, more theoretical interest. The stress of wartime production had the effect of giving an unusually full and rich program, the longest in recent years, with sessions continuing virtually throughout the meeting. Some papers dealt with geophysical prospecting as applied to mining geology; others were concerned with the grand strategy of mineral reserves and thus involved the industrial minerals; such "borderline" subjects were presented before sessions held jointly with the Geophysics Committee or the Industrial Minerals Division.

Jan 1, 1942

Noranda Mines, of Quebec, signed a contract for construction of a $20 million copper refinery at Gaspe, P.Q. The plant is expected to have a 65500-ton daily capacity for both concentrator and smelter. Extensive drilling. around Gaspe has revealed more than 65 million tons of 1 to 2 pct copper in several deposits. Cerro de Pasco Corp. has called a special stockholders meeting for August 19 to obtain permission to engage in the oil and natural. gas business, in addition to its present production of zinc, lead, copper, silver and other metals. St. Joseph Lead Co. recently entered the oil development field. The United States, Canada and Great Britain have agreed to establish a permanent organization to work on unification of engineering standards. General accord has been reached on drafting standards and practices, screw threads, fittings for gas cylinders, and fits and tolerances. Permanent committees will study these fields. Reconstruction Finance Corn approved the largest sum in its history. for a mining enterprise when it loaned $94 million to San Manuel Copper. Corp., of Pinal County, Ariz. The loan will be used to increase production of copper and molybdenum, in what was described as-the biggest copper deposits in the country. Three large gold mining concerns operating in the Philippines told the Philippine Wage Board that they would be forced to close if they had to boost miners&apos; wages 500 to $2 per day. The companies are Mindanao Mother Lodes, Benguet Consolidated, and Balatoc Mining Co.

Jan 1, 1952

By Ángel Nuñez-Meza, Juan Alfaro-Bernedo

La intención del trabajo reportado en este artículo es la de superar las limitaciones que conlleva no trabajar con modelamiento previo, base de datos y un enfoque sistémico. En atención a esta idea, el estudio desarrolló un software para dos circuitos (directo e integral). Como resultado, se recomienda desarrollar un software integral de toda la planta concentradora —chancado, molienda, flotación y eliminación de agua— con diferentes tipos de circuito, en un solo sistema (enfoque holístico); además de migrar a un modelo de servicio en la nube, con el objeto de poder contar con completa disponibilidad.

Sep 30, 2019

By William L. Fink, H. R. Freche

This is the thirteenth paper of a series from the laboratories of the Aluminurrl Company of America presenting the results of investigations of equilibrium relations in aluminum-base alloys prepared from electro-lytically refined aluminum. The ninth paper, on The Constitution of High-purity Aluminum-titanium Alloys,&apos; presented a type of system that had not previously been encountered in aluminum alloys. Subsequent work has shown that there are several similar binary aluminum diagrams including that of aluminum and chromium. The present investigation was limited to the cxtreme alnminum end of the aluminum-chromium system. The first systematic investigation of the aluminum-chromium equilibrium diagram was carried out by Hindrichs.? The resulting equilibrium diagram with some imaginary additions suggested by Guillet3 is shown in Fig. 1. Recently Goto and D6gane4 investigated the constitution of aluminum alloys containing up to 32 per cent chromium, and presented the diagram that is reproduced in Fig. 2. Wide discrepancies in the two diagrams are evident. The following intermetallic compounds have been reported in the literature: A1Crl5,6 AlloCrlzSi,5 AlCr4,6 AlCr3,7 AlaCr.8 Preparation of Alloys and Chemical Analyses With the exception of sample Y4206, which will be described under Determination of Hyperperitectic Liquidus, the alloys were prepared from electrolytically refined alurninum% Of which the analysis is given in

Jan 1, 1933

By David R. Baughman, John C. Gathje, K. C. Oberg, Gary L. Simmons

Santa Fe Pacific Gold Corp. conducted pressure-oxidation pilot plant studies on refractory carbonaceous gold ores from the Twin Creeks Mine in Nevada. The tests were conducted at Hazen Research Inc., Golden, CO, during 1993 and 1994. Laboratory investigations using CIL cyanidation after batch pressure oxidation demonstrated gold recoveries of 90% to 95%. However, pilot plant testing showed that several of the same ore types responded very poorly, with gold extractions of only 45% to 75%. Plant testing was suspended for approximately four months while extensive research was conducted to determine why these ores responded poorly and to identify potential solutions. This paper describes the batch and pilot plant test results, the extensive research activities that eventually identified the cause of the gold recovery problem and the final semicontinuous and continuous pilot plant operations that confirmed possible solutions. Final pilot plant results showed gold recoveries that were consistently greater than 90%.

Jan 1, 1999

By Heinrich Hutchison, Thomas von Moltke, Roelof F. Sandenbergh, Katarina P. Cerovic

Although the cyanidation process for gold leaching has been applied for more than a hundred years, some aspects of it, such as the passivation of the gold and the depassivating action of heavy metals, are still not well understood. In this work the anodic behaviour and surface composition of gold in alkaline aqueous cyanide with lead additions were investigated using polarization experiments and XPS. It was found that lead in the solution activated the gold at low concentrations, somewhat more positive than the reversible potential for gold, but that the activity again decreased at higher concentrations of lead. The potential range for the activation of the gold coincides with that where underpotential deposition of lead occurs, i.e. –200 to –600 mV(SCE), as indicated by the surface composition of the gold, shown in figure 1. Note that the concentration of lead on the surface of the gold only increased with time in the bulk plating potential range for lead, where gold is not activated by the presence of lead. It is also shown that up to 20 mg/L of lead added to the solution will activate the gold, provided that bulk plating of the lead is avoided. It is also important to avoid reducing conditions during leaching, where bulk plating of lead may occur, if the gold is to be activated by lead to achieve a high leaching rate, as the bulk plated lead screens the surface rather than activating it.

Jan 1, 2003

By W. Miola, R. V. Ramaoi

"The MSHA prescribed method for the determination of quartz in airborne respirable-dust samples from underground coal mines is the P-7 method, a combination of /ow-temperature, radio-frequency ashing (LTA) and infra7 red analysis (IR). There is no prescribed procedure for quartz analysis in bulk samples of coal and host rock. Dispersive infrared (IR), Fourier-transform infrared (FTIR) and X-ray diffraction (XRD) methods are most commonly used for the analysis of quartz in powders. Several aspects of the experimental procedures, such as the preparation of the analysis sample from bulk samples, ashing techniques, scanning procedures, peak measurement location, calibration techniques, sample amounts, size consist and data interpretation, affect the results from each of the methods differently. Significant differences in analytical results obtained from X-ray diffraction (XRD) and infrared spectroscopy (IR) on the same samples are reported. All studies point to the need for reliable quartz analysis methods.In a recent research program, a procedure for preparing bulk-coal and host-rock samples for quantitative quartz analysis was developed. Further, the results from X-ray diffractometry and infrared spectroscopy for quartz content on identical samples were compared. Calibrations with pure and mixed standards were used to assess the influence of particle-size distribution, matrix and calibration on the analytical results. In this paper, several issues concerning the measurement of quartz in the samples of coal, host-rock and airborne respirable dust from mines are outlined and quantified. IntroductionThe literature on coal-mine airborne-dust control has identified a need for a better understanding of the sources, mechanisms and amounts of quartz in mine airborne respirable dust (Althouse, 1984; Jankowski, Nesbit and Kissel, 1985; Ramani 1988; Qin, 1988; Bhaskar and Xu, 1990; Bhaskar and Li, 1992; Ramani, Qin and Miola, 1991 ). To understand the quartz content in the source materials, bulk samples of coal and host rock must be analyzed. Establishing an analysis procedure for determining the quartz content in bulk-coal and host-rock samples is necessary for identifying the sources of quartz in mines; for establishing the relationships between the quartz contained in the source and in the airborne dust; and for controlling the content of quartz in the mined product and in the airborne respirable dust."

Dec 1, 1996

"The ore currently being milled at Delnite is a high pyrrhotite ore with the gold intimately associated with the pyrrhotite. To get maximum recovery of the gold with the lowest reagent cost, it is necessary to keep the pH as low as possible In the laboratory the best results were obtained with a pH of 10 but in the plant it was found that a pH of 11 was the minimum practical pH. With the n1anual control it was difficult to maintain this figure.The Mines Branch had a conductivity probe (see Fig. 1), developed by Dr. G .G. Eichholz that they wished to try out in plant operation.On June 17, 1963, the probe with all necessary control equipment was installed in the regrind circuit (see Fig. 2) at Delnite Mines. Crushed quick lime is fed at this point but it is also necessary to feed hydrated li1ne at two other points in the cyanide circuit in order to maintain the pH close to 11. 0 throughout the circuit. Only the feeding of the quick lime at the regrind mill was controlled in this test.One thing that concerned me with the operation of the probe was whether the reading on the probe chart would correspond to the pH. A look at the graph accompanying this paper will show that except for very minor variations the graphs of the chart reading and the pH reading are parallel. The upper graph shows that the pH reading and the lime titrations also correspond and that the cyanide titrations appear to have little effect on the pH reading.Table 1 gives the results obtained for the two months before and after the instal1ation of automatic control as well as the two months of control. Unfortunately there was a decided change in ore just after the automatic controls were removed. There was much less pyrrhotitc in the ore than usual thus changing the need for lime and cyanide."

Jan 1, 1964

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

"Nowadays, End-of-Life (EoL) Liquid Crystal Displays (LCDs) are traditionally disposed in landfills. The increasing access to LCD technology over the last years by Brazilian consumers has intensified LCD' s disposal as an environmental and economic issue. This study aims to characterize used LCDs to identify the main components for recycling. Characterization was performed through scrap disassembly and its components were identified, separated, and weighted. LCDs were disassembled and the following divisions were applied: screen, metal frame, polymeric frame, polymeric sheets and electronic part. Some techniques were used to determine the concentration of Indium in the LCD, the glass/plastic ratio and the different kinds of polymers that compose the screen. The techniques used for characterization included inductively coupled plasma optical emission spectrometry (ICP-OES), Fourier transform infrared spectroscopy (FTIR) and thermogravimetric analysis (TGA). This method, when applied to a wide range of LCDs, can allow the development or improvement of an EoL management of LCD.IntroductionWaste Electrical Electronic Equipments (WEEEs) are waste from discarded equipment, such as computers, monitors and cellphones [1]. Over the past years, treatment of WEEE has been emphasized. It occurs due to the technology's advancement that leads to an even larger increase of WEEES [2].Among WEEEs, there are the liquid crystal displays (LCD). LCD technology is applied in cell phones, tablets, computers and monitors. Nowadays, it's the most well known technology when it refers to monitors, due to its advantages over the Cathode Ray Tube (CRT) technology. Some of them are energy saving, smaller size and no radiation emission [3].This feature in the LCD's global market along with the speed at which electronic equipment becomes obsolete affects society economically and ambiently.This issue becomes even more serious when considering the final destination of the liquid crystal displays. LCDs are lead to landfills as other WEEEs. Besides the different materials long degradation time, the environment is damaged by the disposal of the potentially reusable and hazardous materials [ 4]."

Jan 1, 2014

By Carlos Castañeda Reaño

La presente investigación señala la etapa de creación de las organizaciones de seguridad y de SOGESA, funcionamiento, orientación inicial y el programa mínimo de ejecución inmediata y progresiva. El programa de seguridad se inició en 1980. La técnica impuesta para este programa surge de un compendio de la experiencia desarrollado en programas anteriores. La aplicación se dio en la industria metalúrgica de Cerro de Pasco, y luego en la industria azucarera con la Grace Co. de la hacienda Cartavio, no lográndose definir el programa por completo. En este sentido, se perfila el planeamiento de un programa mínimo a través de un estudio a corto plazo de la situación real en SOGESA y se precisa el lugar que ocupa la seguridad e higiene industrial dentro de una organización. Asimismo se describe las necesidades mínimas del equipo de seguridad y protección, como la difusión de la creación de un conciencia de seguridad en cada trabajador a través de charlas, exhibiciones y reuniones con jefes de servicio y supervisores. También se desarrollan otros elementos estructurales de seguridad como las inspecciones, brigadas de voluntarios de seguridad, estadísticas, campaña contra incendios e higiene industrial para la comunidad, respectivamente.

Aug 20, 1963

By D. N. Esfahani, K. Khazen, M. Mohammadi

Electrowinning is one of the nickel recovery processes from solutions obtained from the leaching of nickel sources. Every year significant amounts of nickel products are used in various industrial processes and daily life, such as catalysts or batteries, which are a valuable source of nickel for recovery. Nickel purity is also very important in the electrowinning process, because the amount of impurities in nickel such as sulphur, if greater than 100 ppm, make it unsuitable for use in catalysts and plating. Because sulfur is intrinsic to the sulphate electrowinning system, we needed to investigate parameters that can affect the quality and purity of nickel. In this regard, experiments were performed in static and circulating electrowinning processes. A monitoring and circulation system was designed and built to measure voltage, current and temperature as well as to circulate the solution in the system at a specified rate. It was then observed that nickel ion concentration, pH, using the circulation system and additives, were factors affecting the purity and quality of nickel, and in the best case the amount of sulphur in nickel was below 100 ppm. Keywords: Nickel, electrowinning, sulphur impurity

Jan 1, 2020

By James P. Rider, Charles D. Taylor, Edward D. Thimons

Research was conducted to investigate how ventilation of a mining face is affected when scrubber flow is greater or less than intake flow. Tests were conducted in a full-scale surface test gallery built to simulate a mining entry with a continuous mining ma- chine at the face. Methane gas was released at constant flow at the mining face. Gas measurements taken at six locations near the face were used to evaluate how well the face was being ventilated. Increasing scrubber flow resulted in lower methane levels even when scrubber flow was much greater than intake flow.

Jan 1, 1997

By A. M. Gaudin, D. W. Fuerstenau

By streaming potential techniques, the zeta potential of quartz has been measured as a function of the concentration of dodecylammonium salts at different pH values. These experiments indicate that adsorption of dodecylammonium ions takes place as individual aminium ions until a certain critical concentration is reached in the double layer, at which point the adsorbed collector ions begin to associate into patches of ions, called hemimicelles. Because of its effect on the surface potential of quartz, pH controls the adsorption of dodecylummonium ions. The value of cooperating agents and nonionized constituents of flotation systems is discussed. Previous investigation of the role of pH in the flotation of quartz with anionic collectors is here extended to an inquiry of how the cationic collector, dodecylammonium acetate, is adsorbed at the quartz-solution interface. The equilibrium amount of this collector adsorbed by quartz has already been measured as a function of concentration and pH. The weight of prior evidence has suggested that two mechanisms are involved in the adsorption of this collector by quartz, but with existing adsorption measurements alone it is not

Oct 1, 1955

By W. C. Knoblaugh

Rotary kilns are adaptable to many fuels, but this paper deals principally with the use of powdered coal. The observations and conclusions presented are based on rotary kilns used in the manufacture of basic refractories for steel furnaces. Solid fuels are pulverized for two principal reasons: (I) ease of control, and (2) rapidity of combustion. By the use of pulverized coal, the operator can increase or decrease the fuel supply by small increments and with very little time lag between the change of control and the resultant change in the flame. This is extremely important in this type of furnace, as the temperature range for maturing the clinker is very narrow. By fine grinding, it is possible to increase the rate of burning of the coal, thereby liberating great quantities of heat within a small space in a short time. Under given conditions, temperature is a measure of the heat liberated per unit of time. To attain the temperatures of 2950° to 3150ºF., which are encountered in the manufacture of various steel-furnace refractories, it is estimated that it is necessary to liberate 125,000 to 175,000 B.t.u. per cubic foot of the burning zone per hour. The manufacture of dolomitic refractories is a ceramic process and, as is true in most such processes, the material must be subjected to a certain critical temperature for a certain length of time in order to complete the reaction. If the time of reaction is reduced, the temperature must be increased; in other words, if the rate at which the material flows through the hot zone of the kiln is increased, the temperature of the hot zone must be increased to compensate for this shorter exposure to the flame. Firing with Pulverized Coal Fig. I is a line drawing of a rotary kiln with the attendant equipment indicated in their relative positions. The kiln proper consists of a sloping, refractory-lined steel tube rotating slowly about its longitudinal axis (0.75 r.p.m.), and is countercurrent in operation in that the raw feed is introduced at the stack end and gradually approaches the zone of highest temperature at the lower end, where the fuel is introduced. Before 1930, the usual method of firing a rotary kiln was to store the coal in the pulverized form and then feed from this storage to the kiln as needed. This proved unsatisfactory and dangerous because of dust explosions and the inability to obtain an even feed to the kiln caused by arching of the coal in storage and flooding of the coal feeders. In later years the practice has been to store the raw coal and grind it as it is needed. Such a layout is indicated in Fig. I. The coal is stored in bins, charged from the top and drawn from the bottom into recording scales and then into some type of unit pulverizer. There are a number of good pulverizers .on the market, each incorporating features that the manufacturer considers outstanding.

Jan 1, 1948