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Research on the Thermodynamics of Siderite Roast Decomposition and the Experiment of Magnetic Roasting-Separation

Sep 13, 2010

By Peter Richards, Alexander Lewis-Gray, Mark Davies, Nicholas Katsikaros

"Gekko Systems developed the Gekko Resin Exchange Column (G-REX) in order to optimise the recovery of gold in complex leach-to-electrowinning processes, as an intermediate step using a highly gold-selective resin to isolate contaminant metals. The AuRIX®100 resin produced by Purolite is licensed exclusively to Gekko, with the G-REX column designed specifically for this resin (Lewis-Gray et al, 2015). Operational experience has been gained at the CGT Ballarat Gold Plant in near continuous operation since 2008, treating unclarified concentrate leach solution. The extension of the technology to higher throughputs and more complex chemistry is discussed.Aurix®100 ResinAuRIX®100 resin is a cross-linked polystyrene alkaline resin developed by Henkel (Virnig et al, 1996). The resin beads are off-white in colour, spherical, with a nominal size of 100% +600µm. This resin is highly selective for gold and silver over many metals, by way of extracting precious metal cyanide complexes from leach solutions with a pH less than 11.5. The higher end of the pH scale produces best selectivity according to the order of preference: Au > Ag > Hg > Zn > Ni > Cu > Co > Fe. Purolite produces the resin and Gekko Systems maintains licensing of AuRIX®100 resin for use in its G-REX column as part of its unique suite of gravity gold handling equipment.Significant cost savings over carbon-in-solution (CIS) systems are realised with AURIX®100 resin, of around 4% to 12% in capital savings and 27% to 40% in operating costs (Virnig et al, 2004). Allied to this is that AuRIX®100 resin is not susceptible to fouling, that is, the resin does not load with inorganic salts or organic compounds which would affect the loading and extraction of precious metals. To counter any potential for fouling by inorganic salts, in service a dilute acid wash is carried out periodically on the resin to unblock resin pores."

Jan 1, 2016

By Frank E. Scott

During the past year interest in the use of hydrazine and hydrazine hydrate as a fuel has increased in the United States; For this reason it was felt to be desirable to obtain information on the explosives properties (if these materials in order that hazards inherent in their manufacture, storage, transportation, and use might be evaluated.

Jan 1, 1949

By Katherine A. Klein

Refuge chambers may potentially save the lives of miners during a mine emergency. For this reason, it is crucial that miners know how to operate them. Unfortunately, because refuge chambers provide so many services, they can be very complicated and difficult to operate. Therefore, NIOSH has created this document with suggestions for developing manuals and educational materials. A multidisciplinary team comprised of NIOSH engineers, sociologists, psychologists, health communication professionals, and geologists developed the recommendations contained in this document. These recommendations are based on an evaluation of manufacturers? instruction manuals from both the U.S. and globally, interviews with over 20 mining and safety experts, and an extensive literature review. This research, focused on the best practices for refuge chambers, led to the formulation of this document. It is intended to offer suggestions to manufacturers and mine operators on how to create effective and easy-to-understand training manuals for miners as well as tips to create the most comfortable and usable refuge chambers. It should be noted that these recommendations are not meant to substitute for manufacturer-supplied materials but rather to be used in conjunction with manufacturer?s materials. Manufacturers should always be consulted for up-to-date information about their chamber. Although different states and different mines refer to underground refuges by different names, this guide will simply refer to underground refuges nearest to the face as refuge chambers, whether inflatable from a skid or constructed from steel. Other popular terms for refuge chambers are rescue chambers, rescue shelters, and refuge shelters. Refuges that are nearer to the shaft, whether a prefabricated refuge chamber or one built into a crosscut, will be referred to as outby refuges because of their location in the mine. Outby refuges can be permanent, semipermanent, or portable and are usually located at every other SCSR cache. Outby refuges are sometimes called hardened rooms, outby shelters, and in-place shelters. When discussing outby refuges and refuge chambers collectively, this guide will refer to them as underground refuges. Other terms for underground refuges include refuge alternatives, locations of safety, and safe havens. This document is designed to be read either cover to cover or by specific section. It is recommended that on first read, this guide be read cover to cover. In subsequent readings, manufacturers and mine operators may find it easier to use the table of contents page to locate specific information on parts of the refuge chamber.

Jan 1, 2009

By Jerry C. Tien

Mining in China dates back at least 4,000 years. Today, with no less than 103,000 metal/nonmetal mines and between 40,000 to 80,000 coal mines, China’s mining industry is undoubtedly the largest in the world. Despite improvements in recent decades, seemingly endless mining accidents continue to make the news. Official coal mining deaths were 6,702 in 2003, and 6,027 miners died in 2004; actual figures may be much higher. Added to these were the 2,699 deaths in the metal and nonmetal industries. Most of these accidents were due to CH4 (methane gas) explosions and fires as a result of inadequate mine ventilation de-sign or practices. A good portion of these accidents occur in small, privately run and often technically illegal mines. During the past 10 years, the Chinese government has attempted to crack down on small and often technically illegal mines without much success. The number of accidents and associated fatalities has not significantly reduced. However, there appears to be a new urgency in China’s efforts to step up mine safety in the country. After its worst reported mine disaster in more than a half century, the government quickly paid reparations to families, suspended high-level officials in charge and announced additonal reforms. One of those was the elevation of the central government’s work safety office to cabinet-level status. There has been increased transparency in reporting and investigation of mine accidents and disasters in recent years. There has also been an increase in public criticism by labor leaders concerning the neglect of mine workersafety.1 This article examines the causes of China’s many mining accidents, current legal and enforcement structures, respective mining health and safety related laws and regulations, recent mining industry developments and the latest effort to curtail small mining operations.

Jan 1, 2005

By R. R. Klimpel

"SYNOPSISA discussion of the importance of flotation rate in the analysis of mineral flotation is presented. In particular, the highly interactive nature of the flotation ""system"" is emphasized where there are components of chemistry, equipment, and operating conditions simultaneously involved. It is further shown that: 1) flotation rate must be measured in order to economically optimize the performance of an industrial flotation circuit, 2) that consistent patterns exist in both flotation rate and equilibrium recovery when changing various settings of the system components, 3) that knowledge of these patterns is necessary in order to avoid making system changes that are either self-compensating or dramatically re-enforcing in some particular aspect of performance, and 4) the rate related role of the chemistry component (e.g.frothers and collectors) is often much bigger than is sometimes realized (especially in a negative sense involving overdosing of reagents). INTRODUCTIONFroth flotation is widely usedl-6 in mineral beneficiation processes as a method for separating different types of finely divided solids present in a liquid (usually aqueous) suspension. The approach is based on the contacting of solids with upward moving air bubbles in an agitated vessel where the solids are exposed to chemicals (collectors) which create a condition favoring the attachment of a certain portion of the solids to the air bubbles. This selected portion is then removed in a froth stabilized by chemicals (frothers) and subsequently recovered from the flotation vessel. Depending on the settings of the various components of the flotation ""system"" (see Figure 1) it is possible to achieve a wide range of flotation performance."

Jan 1, 1984

By Philip K. Hopke

A systematic study of the mechanism of interaction of 218Po(RaA) armed by the decay of 222Rn with airborne particulate matter has been made. The rate of attachment of RaA to particles in the diameter range of 0.1 µm to 10.0 µm has been measured as a function of particle size, concentration, and composition, radon concentration, time of interaction, relative humidity and temperature. It was found that under the conditions in these experiments the attachment rate was proportional to the square of the particle diameter and varied with temperature and relative humidity. The composition of the particles apparently has no effect on the attachment. The variation in attachment rate was related to a sticking probability coefficient of approximately 0.02 that varies systematically with temperature and humidity. In addition, the rate of deposition of RaA on the wall of the attachment kinetics system was measured and also found to change with temperature and relative humidity.

Jan 1, 1980

By D. A. Stanley

The Bureau of Mines conducted laboratory-scale experiments to determine whether or not surface waters with a high organic content could be purified sufficiently to be used to replace the natural high-quality deep well water currently being used in the silica flotation step of phosphate rock beneficiation. Waters abundant in organic matter were collected from two central Florida streams, flocculated with a cationic polyethylenimine polymer, and processed in a sand filter. This treatment removed most of the organic materials from the water. Untreated surface water, treated surface water, and distilled water were used to compare the flotation response of the acid insolubles in an amine flotation circuit. Surface water treated with PEI-1000 was shown to be as effective as distilled water for the acid-insoluble-flotation step. Flocculation and filtration can therefore produce water suitable for amine flotation of quartz, which would permit substitution of surface water for deep well water.

Jan 1, 1981

By E. L. Singleton

The Bureau of Mines investigated extraction of aluminum from aluminum-silicon alloys as a means of utilizing domestic aluminum silicate ores for aluminum production. Aluminum was extracted from aluminum-silicon alloys by electrolysis in molten electrolytes of NaCl-KCI-AIC13 and NaCl-KCI-AIF3 in a laboratory-scale cell. Six alloys with aluminum contents ranging from 20 to 87 percent aluminum were tested, and aluminum products of primary grade or better were obtained. More than 80 percent of the aluminum was recovered with current efficiencies as high as 91 percent. Recovery of a metallurgical-grade silicon product from the anode residue by an acid leaching procedure was possible with the 50-50 and 65-35 Al-Si alloys.

Jan 1, 1972

By . José Arango O

El presente trabajo describe las nuevas técnicas de lixiviación aplicadas en Cerro Verde ante un posible desabastecimiento del mineral en un futuro y por ende, ocurra un alza de costos en el tota de la producción. En este sentido, se implementa nuevas técnicas en el el sistema como la lixiviación con curado, la lixiviación en capas delgadas y el retratamiento de los pads, las cuales prolongan la operatividad de sus plantas y mejoran el nivel de ingresos de divisas.

Nov 8, 1984

The following pages discuss the objectives, the background, and scope of work of an industrial engineering analysis of far-,n haulage systems in underground retreat coal mining. This study ran concurrently with an existing industrial engineering study of methods of improving safety and production efficiency in underground pillar extraction. 1. OBJECTIVES The objective of this project was to provide basic data inputs that will inpart knowledge as to the major constraint to pillar extraction sections. Furthermore, the industrial engineering study will suggest ways to optimize haulage systems and to develop more efficient work practices and operational techniques that will maximize equipment utilization.

Jan 1, 1975

By Tapan Goswami

The expectation from the blasting engineers and shotfirers is often that explosives will perform optimally at all times. However, in reality, non-ideal situations exist on mine sites and occurrences of poor explosives performance are common. Often the cause is difficult to identify. Having a good application technique and analysis skills will minimise the risk of poor performance. This paper will discuss the experiences gained by the author while blasting in the Hunter Valley, Australia.

Jan 1, 2003

By R. S. Warfield

Several reconnaissance-type surface and drill core samples of Arctic Northwestern Alaska coals were taken during the summer field seasons of 1964 and 1966 for coking studies. Surface samples were taken from the Kokolik River and the Cape Beaufort areas; core samples were obtained from the Kukpowruk River and the Cape Beaufort areas. Only one Kokolik River surface sample possessed coking properties. This sample, representing an 11.6-ft coal seam, made coke approaching metallurgical quality when a 30-pct portion of selected blending coals was added. Four Kukpowruk River core samples, each representing the same 19-to 20-ft coal seam, were all of about the same coking quality. No differences of coke quality attributable to depth of permanently frozen overburden were found, but the data confirm previously reported information that the 19- to 20-ft coal bed is a potentially satisfactory base coking coal. In the Cape Beaufort area, a core sample with appreciable coking properties was taken at depth from a coalbed determined noncoking in a surface sample.

Jan 1, 1969

By Alastair Torrance, George Boucher

The authors were involved in the Trial Blast work at Chek Lap Kok, the site of the new Hong Kong Airport. As part of that work a series of computer programs including 3x30, QFRAG, DESIGNER and 3DMUCK was employed to predict various aspects of the trial blast programme. These aspects included fragmentation and muckpiie shape. This provided an excellent opportunity for these programs to be calibrated, verified and compared under controlled conditions. The results indicated that computer simulation has reached a high level of sophistication and good correlation between prediction and measured results was found.

Jan 1, 1994

By Walter F. Bradley

CLOSE to 300 members and guests were registered at the Regional Meeting of the Institute in San Francisco. Oct. 3-6, and many other mining men were present at some of the sessions, but failed to register. Headquarters were at the Palace Hotel. Technical papers for the Metals Session were sponsored by the San Francisco Section, whereas the program for the Industrial Minerals Session was arranged by the Southern California Section. Walter W. Bradley, Chairman of the San Francisco Section, opened the General and Metals Session, introducing President Buehler, who gave a hearty welcome to those present. Clyde M. Eye, of the. Benguet Consolidated Mining Co., presented the first paper, entitled "The Economic and Strategic Value of Philippine Metals to the United States." In closing, he urged. that this country retain and control the Philippines because their large

Jan 1, 1935

By Norman] [Seldle

This report describes the development of a mine machinery training system from initial conception through a task and skill analysis, a training system analysis, implementation of a prototype system, and initial validation of the prototype system. The objectives of the training are to improve safety and productivity simultaneously via complete, thorough training. A task and skill analysts was executed for shuttle cars, continuous miners, cutters, loaders, face drills, tractors, and scoops. The prototype training system is for shuttle car operator training.

Jan 1, 1976

By Annie G. Smelley

As a part of research conducted in its mission to effect pollution abatement, the Bureau of Mines, U.S. Department of the Interior, is developing a dewatering technique that allows for disposal of clay wastes, for reuse of water now lost with clays, and for reclamation of mined land. The technique utilizes a high-molecular-weight nonionic polyethylene oxide polymer (PEO) that has the ability to flocculate and dewater materials containing clay wastes. In laboratory experiments, coal-clay waste, potash-clay brine slurry, phosphatic clay waste, uranium tailings, and talc tailings were successfully consolidated. Coal-clay was te was consolidated from 3-. 6 to 57 percent; potash-clay brine slurry was consolidated from 3.8 to 35 percent; phosphatic clay waste from 15.6 to 49 percent; uranium tailings from 15.4 to 67 percent; tailings from talc production from 9.7 to 53 percent; and an acidic Ti02 slurr slurry from 1.68 to 30 percent.

Jan 1, 1980

By Jos. Kalbhenn

MR. G. G. BOWSER: Mr. Kalbhenn's paper is an excellent one and is a concise description of a very interesting piece of work. It is well known that a great deal of preliminary study was given to this job before the final plans were made. It is due to this thorough preparation .chat the work progressed so satisfactorily, smoothly, and safely. The ideas carried out in the construction of the hardwood pack, timbered compartment, inclined raise, loading chute, and steel-boomed room, all contributed to a successful conclusion of the work. The extra care in being certain that the compartment shafts were well timbered was especially necessary on account of the difficult blasting conditions. In other words, the foundations .of this job were well and truly laid. The blasting in this work was very difficult due to the nature of the Strata. Working under an ever precarious roof condition and completing .this job with only two lost-time accidents is a record of which to be proud. The shaft men engaged on this work are also due for praise. I regret I did not visit this work while it was in progress. It was not in lack of interest. This, however, more or less proves that the blasting end .of this job went along with practically no trouble. I have seen the nature of the rock, as I made several visits to the tunnels while they were being put through from the Phalen to the Harbour seam. According to figures in Mr. Kalbhenn's paper, the explosives consumption works out to 1.61 pounds per cubic yard of rock in the solid, or 0.8 pounds per ton. The explosives consumption in the tunnels ran from 2.86 to 3.46 pounds per cubic yard or an average of 1.58 pounds per ton of rock. Of course, the rock in the shaft was blasted in the most economical way possible, as far as powder costs are concerned, as the face advanced at close -wright angles to the strata and gravity was acting with the explosive. The tunnels were driven nearly 'end on' the strata and bottom holes had to be lifted, and I believe there was some re-drilling of ribs left in the floor. I would like to congratulate Mr. Kalbhenn on his very fine paper.

Jan 1, 1944

By J. L. Sanchez

Using a special double-zone transpiration reactor, the vapor transport chemistry of vanadium pentoxide in the presence of water vapor has been investigated. Three possible volatile hydroxides above V,O,(s) are reported in the literature: VO,(OH),, V,O,(OH),, and VO(OH),. In the present study, it was established that VO(OH), is the principal gaseous hydroxide species formed. The predominant reaction was found to be: { } The vapor pressure of VO(OH), was measured as a function of temperature, water pressure, oxygen pressure and flowrate. The results have been used to determine the Gibbs free energy of the above reaction as a function of temperature: { } The results of the present work were combined with thermodynamic data reported in the literature to obtain expressions for the AGO for the reaction above V,0,(1) and the AGO of formation (units in cal/g-mole).

Jan 1, 1993

By G J. Lyman, S A. Tittlemier

International regulations exist to manage the concentrations of mycotoxins such as Ochratoxin A (OTA) and deoxynivalenol (DON) in grains and prevent health risks from excessive exposure to OTA and DON. Since the permitted levels of these mycotoxins are very low (existing maximum levels are in the range of 5 ppb for OTA and 1–2 ppm for DON), sampling for these mycotoxins is potentially challenging. Given that the distribution of infected kernels in a consignment of wheat can be highly heterogeneous, detection by current sampling methods is subject to a high variance. Furthermore, the concentrations of mycotoxins in individual kernels vary over orders of magnitude, intensifying the heterogeneity of the bulk grain.In these circumstances, there is much interest in developing sampling plans that inform regulatory agencies, and mitigate the risk of misclassifying grain shipments as compliant or non-compliant within the global grain trade, when correctly implemented.Experimental data from laboratory and field studies describing individual wheat kernel concentrations of OTA and DON were combined with experimental data describing the variance due to the analytical methods used for OTA and DON to calculate the sampling distribution for wheat having various levels of contamination. This work has focused on quantifying the heterogeneity of samples at the point of submission for analysis and within subsequent sample preparation to arrive at total sampling distributions that include uncertainties due to the intrinsic heterogeneity and the analytical uncertainties. The sampling uncertainty that relates to the difference between the primary sample analysis and the true lot analysis is not included as it has been dealt with elsewhere.CITATION:Lyman, G J and Tittlemier, S A, 2017. The sampling characteristics of grains contaminated by mycotoxins, in Proceedings Eighth World Conference on Sampling and Blending , pp 281–294 (The Australasian Institute of Mining and Metallurgy: Melbourne).

May 9, 2017