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By Albert L. Toenges

A phase in strip mining of bituminous coal is the overturning of the surface of the land. The purpose of this report is to acquaint the operators and others interested in stripping with the work that has been done in certain States to reclaim the surface of land from which the coal has been removed by this method of raining. The preparation of this manuscript follows an extensive study of the subject in the field in the course of which a large number of strip mines were visited. ACKNOWLEDGMENT The information used in the report was obtained through the courtesy and cooperation of the operators of the mines visited, State officials and educational institutions, and others interested in the subject.

Jan 1, 1939

By A. B. Cecala

Video technology coupled with data logging exposure monitors have been used to evaluate worker exposure to different types of contaminants. However, previous application of this technology used a stationary video camera to record the worker?s activity while the worker wore some type of contaminant monitor. These techniques are not applicable to mobile workers in the mining industry because of their need to move around the operation while performing their duties and tasks. The Helmet-CAM is a recently developed exposure assessment tool that integrates a person-wearable video recorder with a data logging dust monitor that are worn by a miner in a backpack, safety belt, or safety vest to identify areas or job tasks of elevated exposure. After a miner performs his or her job while wearing the unit, the video and dust exposure data files are downloaded to a computer and then merged together through a NIOSH-developed computer software program called EVADE (Enhanced Video Analysis of Dust Exposure). By providing synchronized playback of the merged video footage and dust exposure data, the EVADE software allows for the assessment and identification of key work areas and processes, as well as work tasks that significantly impact a worker?s personal respirable dust exposure. The Helmet-CAM technology has been tested at a number of metal/nonmetal mining operations and has proven to be a very valuable assessment tool. Mining companies wishing to use this technique can purchase a commercially available video camera and an instantaneous dust monitor to obtain the necessary data, and the NIOSH-developed EVADE software will be available for download at no cost on the NIOSH website.

Feb 27, 2013

By A. Taylor, J. Shelegey, H. Sullivan, J. Doucet

"Historically, performance at Vale’s Clarabelle Mill was measured by Mill throughput and Mill recovery. After the economic collapse in 2008, a series of reviews were performed to drive improvements in business efficiency. These identified that product quality (e.g., concentrate grade, variability in concentrate grade) had a profound impact on downstream processes and suggested that improved control of these parameters would generate the greatest value for the customer (the Copper Cliff Smelter) and the company (Vale). Consequently, a movement was initiated to transform the Mill operating philosophy to consider customer needs as paramount. Systems and strategies used to drive the transformation are described. In 2011, an unexpected furnace failure resulted in decreased capacity at the Copper Cliff Smelter. In response, a two-stage change in production strategy was developed at Clarabelle. The first stage was to modify the ore blend feeding Clarabelle so that the concentrate grade could be significantly increased with minimal impact on recovery. The second stage was a circuit modification to ensure the elevated concentrate grade could be sustained. Execution of the first stage was complete five days after the failure and the second stage was complete within 10 weeks. Steps involved in each stage are outlined and the overall benefits are presented.INTRODUCTION Clarabelle Mill is located in Copper Cliff, Ontario, Canada (approximately 350 km north of Toronto). The Mill treats copper (Cu) and nickel (Ni) sulphide ores. The primary diluents are pyrrhotite (Po) and non sulphide gangue rock (Rk). The process description of the circuits at Clarabelle is documented in the paper by Taylor, Doucet, Blanchette, Barrette & Lawson (2012) in this Proceedings and will not be repeated. The Mill treats ore containing Cu, Ni and platinum group elements (PGE’s) and produces two concentrates; a Cu concentrate and a bulk Cu/ Ni Concentrate (referred to as nickel concentrate). The Cu concentrate is sold to market while the Ni concentrate is thickened at the Mill and pumped to Vale’s smelter complex in Copper Cliff Ontario for further processing. Since commissioning in 1971, Clarabelle Mill has undergone many circuit changes to suit the changing needs and wants of our customers, both internal and external. The Mill processes ores of varying quality, based on mineralogy and size and until 2009 the Mill daily performance was primarily based on throughput. The second key performance indicator (KPI) of “good” or “bad” performance was quality of the concentrate and third; Mill metal recoveries. There were other plant level KPIs such as flotation feed grind size, slurry densities and mass flows to the separation circuit, but for the most part each day was good or bad depending on how many tons were processed through the Mill."

Jan 1, 2012

By John P. Weir

The planning of an underground mine for successful extraction of a bedded deposit in sedimentary rocks requires the integrated evaluation of many interdependent problems. The development and coordination of feasible solutions are the responsibility of the mining engineer. One of these problems will be discussed herein; this is the design and .layout of mine workings to secure effective control of the strata above and below the deposit. The objective is the simplest possible repetitive system permitting safe maximum recovery at optimum cost. Mining conditions to be encountered must be predictable. The best mining equipment is ineffective unless strata are controlled. Conversely, a mining layout is only of academic interest, if equipment can not be adapted to work it with adequate provision for ventilation, compliance with mining laws, proper ingress and egress and other practical requirements. Strata control, then, is but one of the mining engineer's problems, and the solutions must be worked out concurrently with solutions to other problems. Dr. Karl F. Fetters in his introductory remarks before the Fourth International Conference on Strata Control and Rock Mechanics at Columbia University said that mining engineering ?has come from the stage of empiricism backed by intuitive reasoning, to where it is based on fundamental scientific and engineering principles?. The standard curriculum in mining engineering now reflects such a change. In common with other branches of engineering education, less and less emphasis is placed on practical skills and more and more on broad scientific education. Science, research and the quest for basic truth are stressed, while descriptive courses and the teaching of specific skills are limited.

Jan 1, 1966

ABSTRACT Understanding process histories and worker exposures in nickel production operations is critical in determining the role nickel compounds play in respiratory cancer incidence. As part of a series on Vale Canada’s (previously known as Inco) nickel processing operations, this paper includes descriptions of Ni electrolytic operations at refineries in Port Colborne, Ontario (1922–1984), and Thompson, Manitoba (1961–present). Industrial hygiene measurements, by area and personal sampling, of workplace aerosols at these operations are reported.

Jan 1, 2014

By Ray Hutton, Darrell Liebno, Taro Nonaka

Background Population growth and increasingly stringent regulatory controls on water quality across North America have resulted in municipal governments investing heavily in infrastructure to control what are known as Combined Sewer Overflows (CSOs).These are events which occur when combined sewers exceed their conveyance capacity during periods of heavy rainfall or snowmelt. The city of Atlanta, Georgia is one such municipality; with a population of over450,000 within city limits and a sewer system servicing 1.2 million including adjacent jurisdictions, the City of Atlanta has a Combined Sewer System (CSS) encompassing approximately 15% of its total 3,540 km (2,200 miles) of sewers. Atlanta’s CSO discharges to local watercourses began to draw fire from environmental groups in the1980s. As a result, in the early 1990s, the City constructed a series of CSO control facilities which provided screening and chlorination at seven CSO discharge points across the CSS watershed. Unfortunately, these facilities were not capable of handling all of the overflows generated due to heavy storm events; frequently, untreated water was bypassed around the treatment facilities. The federal Environmental Protection Agency (EPA) deemed that water quality standards were being violated by these discharges, and a suit was brought against the City to force a higher standard of compliance. As a result, the City entered into a federal Consent Decree which would bring CSOs into compliance with federal standards by 2007. A critical component of this plan was the design and construction of the West Area CSO Tunnels and Pumping Station. In February 2003 the City’s Department of Watershed Management retained the services of Jordan Jones & Goulding/Hatch Mott MacDonald/Delon Hampton Associates (JDH Joint Venture) to design and provide construction management ser-vices for the project, which was designed to capture combined sewage from three of the City’s existing CSO facilities on the northern end of the CSS watershed. The design consisted of two connected tunnels which would convey the wastewater originating from the North Avenue, Clear Creek, and Tanyard Creek CSO facilities to a submersible wet well pumping station located at the R.M. Clayton Water Reclamation Center (WRC). Since the majority of the effluent stream consisted of storm water, the City elected to design and construct a separate treatment plant. This plant was designed under a separate contract, and is currently under construction.

Jan 1, 2007

By D Woolmer

Since January 2019, BHP Olympic Dam have been trialling the use of a drone based LiDAR mapping system for the purpose for surveying stope voids. This new technology utilises Simultaneous Location and Mapping (SLAM) algorithm providing positioning, stability and collision avoidance in GPS denied environments. Implementation of this system utilised underground personnel trained in the equipment’s use. The study’s intention was to evaluate the effectiveness of this equipment versus traditional surveying methods in regards to quality, safety and productivity. The trial results showed a marked improvement in the quality, productivity and personnel safety when conducting surveys. The use of the drone and LiDAR system reduced personnel and equipment requirements for surveys, thus allowing these resources to be deployed elsewhere. The technology’s simple and rapid deployment allowed multiple surveys to be conducted during a 12 hour shift, including ad-hoc work with minimal disruption to underground operations. After the drone’s initial trial, further work was conducted to utilise the Hovermap LiDAR scanner on other platforms to increase utilisation. A mounting system was created allowing the LiDAR to be mounted on a remotely operated loader or vehicle. This enabled drawpoint scans to be taken directly after production completion, resulting in faster stope close outs and drive scans for convergence monitoring. Implementation of the LiDAR system has resulted in improvements in the stope production cycle by reducing delays previously associated with data capture. The increase in the volume and quality of data has also allowed in-depth back-analysis of stopes in new mining areas to be conducted, which have driven improvements in the design process.

Mar 15, 2021

By David Seaman, J-P Franzidis, Emmy Manlapig

"A new device has been developed to directly measure the bubble loading of particle-bubble aggregates in industrial flotation machines, both mechanical flotation cells as well as flotation column cells. The bubble loading of aggregates allows for in-depth analysis of the operating performance of a flotation machine in terms of both pulp/collection zone and froth zone performance. This paper presents the methodology along with an example showing the excellent reproducibility of the device and an analysis of different operating conditions of the device itself.The device has been used to investigate the froth selectivity of attached particles. Simultaneous measurements were made using a different froth recovery measurement technique in the same flotation cell. A comparison of these techniques shows that in this case, particles are selectively detached from bubbles at or near the pulp-froth interface.INTRODUCTIONA flotation cell can be considered to operate in two distinct phases or zones; namely the pulp or collection phase and the froth phase. The pulp zone is responsible for the formation of hydrophobic particle-bubble aggregates, whilst the froth phase is responsible for the separation of these aggregates from surrounding suspended hydrophobic and hydrophilic particles. Thus, the froth phase is the grade determining phase in flotation. A measurement of the bubble load (the mass of particles attached to air bubbles in units of mass/volume) will enable the analysis of the performance of both the collection zone at creating bubble-particle aggregates and also the froth zone at separating these aggregates from surrounding pulp.A measure of froth zone performance that has been used extensively in flotation research is the Froth Recovery, Rf, of a particular system. Froth recovery is defined as the mass of particles collected in the concentrate launder by true flotation as a fraction of the mass of particles entering the froth phase. The measurement of bubble load allows for this term to be calculated easily, rather than having to go through the laborious task of, for example, changing froth depths to determine this performance criterion (Contini et al., 1988; Vera et al., 1999b; Feteris et al., 1987)."

Jan 1, 2004

By J. M. Garcia

This paper highlights several management practices from the oil and gas industry to support the proposition that financial performance in the finite, non-renewable resource business relates more to upstream rather than downstream activities. Based on the analysis of nine oil and gas companies, this study supports a previous study involving fourteen mining companies that showed reserves growth is one of the main levers of value creation in mining. Interestingly, this study also finds that the oil and gas industry has been historically more profitable than mining. The reason, it is argued, is that oil and gas companies count on management practices that focus primarily on the upstream segments of the business, compared to the traditional downstream focus of mining. This paper delves into these ideas to conclude that what mining may need to improve its competitive advantage is a new organizational framework. Another conclusion is that the upstream management focus is vital not only for strategy formulation in the resource business, but also for policy formulation in economies based on the export of finite, non-renewable resources.

Jan 1, 2011

By Dennis R. Kasper

This study evaluates selective environmental impacts of two distinct in situ mining techniques. In situ leaching of uranium, porphyry copper and native copper and in situ borehole (slurry) mining of uranium, sandstone, and pebble phosphate ores are the techniques and minerals investigated. The potential impacts onsite in the desert southwest (porphyry copper), Michigan (native copper), Texas and Wyoming (uranium), and Florida and North Carolina (phosphate) are addressed and discussed. The study emphasizes those impacts which are unique to in situ solution leaching and borehole slurry mining. Impacts which are characteristic of all construction projects in the general geographical areas investigated, such as socioeconomic effects on surrounding communities and site-specific impacts, such as rare and endangered species, are beyond the scope of this study. For each of the in situ processes and associated ores investigated, the physical and chemical characteristics of the systems are described, the toxicity of the leaching solutions are presented, and the potential impacts on the environment are developed.

Jan 1, 1979

By Isabelle Lamb, Manfred K. Lechner, Daniel N. Adams

Sydney Australia’s M5 East Motorway connects southwestern suburbs to the airport. Central to the project are twin 3.8 km roadway tunnels which are mostly driven through rock. In order to come up with the winning tender, the project team developed several unique approaches for tunnel excavation and support. The project’s flat roof with thin shotcrete lining, 20 m wide underground intersections, thixotropic-grout sheathed rockbolts and cablebolts, and new shotcrete testing methods all differ significantly from traditional concepts. This paper presents the design basis and construction methods used to achieve the 100-year design life required by the project’s owner.

Jan 1, 2001

By D David

Amongst those whose task it is to design tumbling mills and other comminution machines there is an almost religious divide between devotees of the Bond method and devotees of other methods developed in more recent times. For a decade or so the issue was between the Bond power-based methods and the JKMRC (JK) simulation based approach. The newest method to challenge the status quo is power-based and was developed by Steve Morrell. As the title suggests, this paper will take some liberty at concluding that Fred Bond and Steve Morrell may be separated by history, but not by their approaches to their individual contributions to the science of comminution. Another driver for the paper is that although it is good to have diversity of thought, the existing divisions are problematic for those of us signing public disclosure documents. If alternative design methods produce materially different outcomes for the mill duty, then at least one of them is wrong or being used incorrectly. At some point the unsustainable argument may need to be put in a court of law that we metallurgists have two or more materially different design methods, each of which is correct! Therefore, perhaps a resolution is needed before this occurs?The works of both Fred Bond and Steve Morrell are each directly related to their contemporary grinding mill design and operational environments. Both their approaches are empirical, borne of observing and measuring real world situations. Both worked with theories that preceded them, gathered their own data and then each saw shortfalls in the status quo.Fred Bond was an escapee from revolution, a victim of The Great Depression, and had several near death experiences during his early site-based career. Perhaps he was fortuitously rescued from himself when asked by Allis Chalmers (A-C) to set up its rock testing laboratory in Milwaukie in 1930. Fred’s testing led him to conclude that neither the Kick nor the Von Rittinger theories explained his measurements. His writings on the failings of these old theories caused a divide between devotees of the old and new methods at that time. After many years, and much thought and plotting of data (the old way!), he came up with his now-famous equations (and his Third Theory) which have stood the test of time, certainly in the world of Bond-era machines.Coming from England via several African diamond mines, Steve Morrell immersed himself into the comminution world of the JK in Brisbane about a decade after Fred passed on. The JK had developed its semi-autogenous grinding (SAG) simulation framework using its own pendulum breakage tester, itself a derivative of the twin pendulum impact device invented by Bond decades earlier. At the JK Steve developed his authoritative Tumbling Mill Power equations and was involved in real world analysis of comminution problems on the global stage. Steve’s JK experience coincided with the demise of the rod mill, the rise of autogenous grinding (AG) and SAG milling and a rapid expansion in concentrator capacity.Morrell left the JK to pursue his own interests, which included ongoing consulting work, now demanded by the comminution world. He then turned to investigating a growing list of discrepancies between the opinions of designers and theoreticians, and the factual outcomes. The Morrell Method of design arose from this re-examination of ore testing, real world operating data and these glaring and expensive discrepancies between design and outcome. The elements necessary for a relook at the world of rock breakage were in place!CITATION:David, D, 2017. Steve and Fred would have been mates – a comminution design evolution story, in Proceedings MetPlant 2017, pp 2–11 (The Australasian Institute of Mining and Metallurgy: Melbourne).

Sep 11, 2017

By S. B. Mishra

Ni-20Cr metallic coating was deposited on a Ni-based Superalloy (3Fe-19.5Cr¬0.3Ti-Balance Ni) by a shrouded plasma spray process; NiCrA1Y was used as a bond coat. Erosion studies were conducted on uncoated and plasma-spray coated superalloy specimens using an air-jet erosion test rig at a velocity of 40 m/s and impingement angles of 30° and 90°. The coating has been characterized for porosity, microhardness and microstructure and X-Ray Diffraction (XRD). An electron probe micro analyzer (EPMA) was used to obtain X-ray elemental mappings of the coating along the cross-section. Scanning electron microscope (SEM) with EDAX attachment was used to analyze the eroded surfaces.

Jan 1, 2005

By A. G. Starliper

The Bureau of Mines made laboratory investigations to determine the feasibility of utilizing fine tungsten wires to reinforce a number of nonferrous metals and alloys and a superalloy, S-8l6. The composites of tungsten filament and metals were chosen to attain elevated temperature strength and corrosion resistance. Oriented clean or precoated tungsten wires were incorporated with the other metals by extrusion, swaging, and infiltration casting. Although widely varying characteristics were found in the composites, none were considered satisfactory for high-temperature use, chiefly because of reactions between the matrix metal-tungsten surface. Diffusion, solution, and chemical reactions between matrix and tungsten wires were sufficiently slow for some combinations, such as 15 v/o 8-816, to exhibit increased high-temperature strength for a limited time. A few metals failed to wet or bond to the tungsten surfaces, while a few responded after precoating with a third metal.

Jan 1, 1968

By Thomas J. Peters

In 1984, at the request of the Bureau of Land Management, the Bureau of Mines studied 7,000 acres of the 9,240-acre Little Blitzen Gorge Wilderness Study Area in Harney County, OR, to evaluate its mineral resources. The study area is dominated by a 1,500-ft-deep canyon that was carved by Pleistocene glaciers in gently westward-dipping homoclinal flows of Miocene Steens Basalt. The Bureau reviewed pertinent literature and county mining records During the field investigations, 18 rock samples were collected from basalt dikes, breccia, fractured or porphyritic flows, and 20 alluvial samples from gravel accumulations. Mercury anomalies from sampling by the Oregon Department of Geology and Mineral Industries could not be verified. The mercury might have originated -From the Pike Creek Formation, a known mercury-producing unit that may extend into the study area beneath the Steens Basalt. Any epithermal deposit at depth would be expensive to explore and develop.

Jan 1, 1986

By M. Gaula

"Gold bearing deposits of the Witwatersrand basin are generally less than 2m thick and require conventional narrow-reef mining methods for extraction and employ explosives as a means of rock breaking. Optimal utilization of explosives is dependent on the overall design of the blast. The under-utilization of explosives arises when shot-holes are drilled inconsistently, overcharged, and when tamping is absent. This can be rectified by emphasizing the importance of good drilling practices as part of induction programmes and refresher courses. The project was aimed at determining whether or not explosives are being optimally utilized at project site. This was investigated through a study of the properties of explosives, mine standards, and recommendations for usage. Underground observations were made to determine whether or not mine standards were being adhered to. Historic data was obtained to establish the historic relationship existing between the quantity of explosives used (kg) and the production output (m2). This was then compared to the quantity of explosives the mine expects to use per unit of production. The results obtained were analysed to determine the presence and extent of over- or under-utilization. It was found that explosives are being under-utilized at the mine. More explosives are ordered than expected per unit of production. The explosives’ properties are not thoroughly exploited during blasting, thereby requiring the use of more explosives than prescribed. Paper written on project work carried out in partial fulfilment of BSc. (Mining Engineering)"

Jan 1, 2015

By Paul M. Tyler

The literature on radium is already voluminous, but mcuh of it is too technical to be intelligible to the average reader, and there is no single publication that covers certain economic features of the radium industry. As a result of the renewed interest in the possibilities of domestic carnotite deposits a number of requests have been made to the Bureau of Mines for information, more particularly with reference to the business aspects of the industry. In order to meet this apparent need, the present paper has been prepared from material available in the files of the bureau. The technical data are compiled from various sources and are believed to be reasonably dependable, but the attempt has been not so much to achieve meticulous scientific accuracy as to brim; together facts of industrial significance and popular interest. GENERAL DESCRIPTION Radium is a brilliant white metal that melts sharply at about 700°C. and volatilizes appreciably at that temperature. With an estimated specific gravity of nearly 6.0, it is more than twice as heavy as aluminum and 25 per cent lighter than irons. Although it has been isolated in its metallic state, it is not used in that form, partly because it tarnishes rapidly even in dry air (forming a nitride), partly because of the greater expense of reducing it to metal, and partly because of the difficulty of dealing with such minute quantities of material. It is used always in the form of its compounds, the most important of which from the vie point of utilization are the bromide, chloride, and sulphate.

Jan 1, 1930

By W. O. Crosby

WASHINGTON CAMP, in Santa Cruz county, Arizona, is a small and little known mining district situated on the lower, eastern slope of the Patagonia mountains, about 20 miles east of Nogales and a like distance south of Patagonia Station on the Sonora railroad, which connects it Benson, 83 miles from Nogales, with the main line of the Southern Pacific. This district is also about 4 miles north of the international boundary, 35 miles west of Bisbee and 40 miles north of Cananea, in Sonora. The topography of the district, which lies at a general elevation of 5,500 ft. above the sea, is only very moderately rugged, and presents no obstacles to mining operations. Although some of the claims of the camp, including the Pride of the West, Belmont and Holland, were extensively worked for silver 25 years ago, they passed, at moderate depths, as in so many other districts, out of the argentiferous lead carbonate and sulphide into zinc, copper and iron sulphides; and for two decades the camp was abandoned and almost forgotten. In recent years, however, its apparent possi¬bilities as a copper producer have led to a revival of mining activity; but not, as yet, with conspicuous success. Although economically relatively unimportant, the deposits of Washington Camp are, mineralogically and structurally, nevertheless, typical examples of ore-bodies developed in connection with the garnet ledge now recognized as a normal feature of granite-limestone contacts; and, in the opinion of the writer, this is an instance where a minor example is yet essentially normal and capable of throwing important light upon the origin and genetic relations of the type.

Nov 1, 1905

By A. A. Cochran

The purpose of this Bureau of Mines research was to investigate the theoretical and practical aspects of using ionizing radiation to promote chemical reactions that are of interest to metallurgists, and to carry out a radiation study of a suitable reaction. The effect of 44,000 roentgens per hour of 120,000-volt X-rays on the chlorination of highly pure mixtures of rutile, carbon, and various catalysts at temperatures up to 540° C. is described. At these low temperatures, recoveries were very low; however, in the eight different systems studied, an increase in yield due to X-rays was statistically significant in two instances and was of borderline significance in a third instance. In the other five systems, the differences in yield were not significant. Impurities and added catalysts caused relatively large variations in the yield of TiC14 from the reaction. Although the catalysts employed were reported in the literature as positive catalysts for the reaction, most of them were negative catalysts for the highly pure system studied. With only one exception, each increase in the purity of the charge resulted in a decreased yield of TiCl4. The experimental results indicate that many substances catalyze the reaction studied and suggest that the differences in reactivity of the charge stocks may be due to their various contents of positive and negative catalysts.

Jan 1, 1962

By N. N. Malila, N. R. Shoko

The ever-increasing pressure on the profit margins of ferro-chrome producers and the gradual depletion of deposits of rich hard lumpy chrome ores calls for the ferrochrome industry to maximise the use of fine fractions of concentrates and friable chromite ores. Zimbabwe is endowed with huge deposits of refractory and friable ores that occur on and off the Great Dyke complex. The conventional metallurgical process of smelting of chromite ores in submerged arc furnaces is favoured by the use of refractory hard lumpy ores. The requirement to use all lumpy ore has been circumvented to a large extent at Zimbabwe Alloys. The use of briquetted chrome ore fines in the production of Ferrosilicon Chrome and High Carbon Ferrochrome has yielded positive results over a period in excess of twenty-five years. Of the three industrially used methods of agglomeration of chromite ores; sintering, pelletisation and briquetting, briquetting is preferred because the other two are associated with higher capital and operational cost. Zimbabwe Alloys has developed operational and technical expertise on the briquetting and utilisation of chromite ore fines and concentrates. Variations in the quality of available chromite ore fines imply that their amenability to briquetting is a dynamic problem. Appropriate briquetting parameters to guarantee quality briquettes are essential to the successful use of briquetted chromite ore fines. In developing a technology for briquetting of chromite ores, it is important not only to study the mineralogical and grain-size characteristics of the chromite ore fines but also to make an informed choice of the type and quantity of the binder and the conditions for producing a physically and chemically competent green and cured briquette. This paper discusses Zimbabwe Alloys' experience on the briquetting process and the advantages derived in the smelting of the briquetted chromite ore fines in comparison to the use of conventional lumpy chromite ore with respect to improvements in chromium recovery and as a consequence related efficiencies and unit cost of production.

Jan 1, 2004