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By Benjamin W. Haynes

The Bureau of Mines conducted research to provide technical information needed to devise waste management plans for the processing of manganese nodules. Studies included summary descriptions of Pacific manganese nodules, process options and flowsheets, methods for characterizing nodules and their tailings, and results of analyses of laboratory and pilot-plant generated tailings. This information is the result of a cooperative research effort of the Bureau of Mines and the National Oceanic and Atmospheric Administration (NOAA), with NOAA providing funding and the Bureau conducting the research. A summary of the extensive literature review is provided for manganese nodule mineralogy, chemistry, processing techniques, and methods of analyses. Characterizations and analyses of laboratory-generated tailings and slags are given, as well as the results of the leaching studies on these waste materials. Leachability was determined by three standard leachate tests- the Environmental Protection Agency (EPA) extraction procedure (EP) toxicity test, the American Society for Testing and Materials shake extraction test, and the U.S. Army Corps of Engineers-EPA seawater elutriant test. While the wastes generated in the laboratory may not be entirely representative of those to be generated in full-scale plants, results of these studies provide a positive indication that commercial recovery of cobalt, copper, manganese, and nickel from manganese nodules would be environmentally acceptable.

Jan 1, 1985

By A. E. Aho

"The Pacific Nickel property lies 7 miles northwest of Hope and 100 miles east of Vancouver, in the Coast Mountains of southwestern British Columbia. Nickel-copper sulphides were discovered in ultrabasic rocks on this property in 1923 and the deposits were explored by Pacific Nickel Mines until 1937, then again between 1951 and 1954 by Pacific Nickel Mines and by Newmont Mining Corporation through its subsidiary,Canadian Ore DepositsWestern Nickel. The property was studied by C. E. Cairnes (1) in 1924, by W. E. Cockfield and J. F. Walker (2) in 1933, by H. C. Horwood (3), (4) in 1936 and 1937, and by the writer in 1951 and 1952. Except for a few thousand tons for trial shipments, the property has never been mined. Indicated ore reserves now total somewhat over one million tons averaging about 1.4 per cent nickel and 0.5 per cent copper, with lesser values in precious metals and cobalt.GEOLOGIC SETTINGThe nickeliferous ultrabasic rocks form part of the core of a 15-milewide block of Late Palæozoic metamorphic rocks and Mesozoic intrusives which extend north-south between the coast batholith of British Columbia and the Chelan batholith of Washington. Margins of this block are faulted in part against less metamorphosed volcanic and sedimentary rocks largely of Jurassic and Lower Cretaceous age (Geo/. Surv., Canada, Map 737 A, 1942). Serpentinites, suggestive of deep transgressive structure, occur within the block, and also at its east margin along faults which are southern extensions of the regional Yalakom-Fraser River fault zone. Some of the other mineral deposits in the Hope area appear to be spatially related to these major faults.The mineralization at Pacific Nickel occurs almost exclusively within a stock-like mass of ultra basic rocks which mingle with, and partly cut, a larger batholithic mass of genetically related diorites and norites of late Mesozoic age (Figure 1 ). The ultra basic mass consists essentially of fresh, medium-grained hornblendic pyroxenite with peridotitic cores and with a remarkable margin of pegmatitic hornblendite. The most hornblendic rocks appear to be chiefly products of reaction and replacement of the pyroxene and olivine rocks. The mineralization consists of disseminated and massive pyrrhotite, with subordinate pentlandite and chalcopyrite, amongst fresh olivine, bronzite, and, Jess commonly, augite and hornblende. Both the ultrabasics and mineralization are cut by small hornblenditic and dioritic dykes, and by veins and alteration zones."

Jan 1, 1949

By Peter J. Szabo

Introduction This is the Pacific Rim. Nearly three fourths of the world's population live on or near its border. In the recent past, on any given day, one could find traversing its„ borders pirates, smugglers, gunrunners, missionaries, slave traders, tourists, and businessmen. If one were not too observant, he would notice that over the last several years the ocean traffic in the Rim has pretty much stayed the same--Polynesian outriggers, passenger ships, general cargo vessels, ore carriers, and oil tankers. If he were to look a little closer, he would notice some coal colliers. A still closer look would reveal that most of them were hauling metallurgical coal destined for the steel mills of Japan, Taiwan, or Korea. If his senses were keen, he would observe that not only were the number of colliers increasing dramatically, but also that a relatively new cargo was being carried to those countries as well as additional areas in the Pacific Rim., This new cargo thermal coal holds the promise of not only exceeding the metallurgical coal trade, but significantly cutting into and decreasing the already vast oil tanker business throughout the Pacific Rim. The high price of crude oil as a result of the oil embargo in the Middle East in 1973-74 has forced the Pacific Rim countries to convert to coal, and as a result, the coal resources of the Rim are being exploited at an ever-increasing rate. Although coal produced outside the Pacific Rim does enter its borders for ultimate consumption from such places as South Africa and the East Coast of the United States, the vast majority of thermal coal that will enter this booming market place will be sourced from countries within the Pacific Rim. Accordingly, this paper will provide an overview of those sources with particular emphasis on the non-communist block nations. This is not to say that countries such as China and Russia will not be players in the Pacific Rim thermal coal arena, but that -most consuming countries in the Rim are basing the majority of their near-term sourcing requirements from countries that provide a stable source of supply. Pacific Rim Coal Resources Figure 1 is a map of the Pacific Rim countries and identification of major coal resource locations within its border. Going in a clockwise direction, the following countries will be the major suppliers of thermal coal through the year 2000: Australia, Indonesia, China, Russia, Alaska (U.S.), Canada, United States (Utah, Colorado, Wyoming, Montana), and Colombia, South America. Other countries such as New Zealand, Malaysia, Philippines, Korea, etc., will play a role in supply, but compared to the ones previously mentioned, will only have a minor impact. When one looks at the vast stretch of ocean that separates the sourcing countries from the consuming countries (Japan, Korea, Taiwan, Hong Kong, Singapore, etc.), one realizes that costs of transportation will play a significant role in determining which countries and in what quantities coal will be purchased. Figure 2 for comparative purposes, shows

Jan 1, 1982

By George E. Edwards

Pacific Rim markets for export coal already represent a larger market than the total tonnage imported into the European Community countries and they will continue to expand. The largest importers will continue to be in the sector comprising Japan, Korea, Hong Kong and Tai- wan. It is likely that the total Pacific Rim markets will reach 206 m.t.p.a. by 1990 and 290 m.t.p.a. by 2000, with the major growth in steam coal demand. Australia has an efficient coal industry, represents a stable long term source of supply and is favourably situated geographically to continue to be the largest single supply source.

Jan 1, 1982

By D. G. Ball

Other than being used to convey fill material for the gob stowage or building of ribside packs on advancing longwell faces, pneumatic conveying has not been used for the transport of materials on a large scale in mining operations. The technique is extensively used in the wood products industry for conveying wood chips, limestone and other ingredients for the manufacture of paper, for the transfer from railcars, barges or ships to silos or stockpiles and further transfer into the pulp mills. This method of material transfer has the distinct advantage of transporting suitable material over horizontal and vertical distances within the same system. In considering material associated with mining, this includes, ore, coal and rock up to 4 inch cubed size, throughputs of 200 tons per hour over horizontal distances of 3000 feet or vertical lifts of 2000 feet. In recent years tests have been carried out to determine the physical and economic limitations of pneumatic hoisting, the results of which have led to the installation of two fully productive coal hoisting systems at mines of the National Coal Board in Great Britain. The equipment used for the pneumatic hoisting of coal or waste rock is described in this paper, together with a brief history of the tests which led up to the installation of the two hoisting systems in Great Britain.

Jan 1, 1977

By James R. Strong

Before getting into the subject of packaging and materials management, please permit me to introduce you to MICRO SWITCH. MICRO SWITCH, A Division of Honeywell Inc. is located in Freeport, Illinois. We manufacture and market thousands of types of precision snap-action electrical switches. Most of them are used as components by other manufacturers in industrial and commercial products. MICRO SWITCH also offers a broad line of industrial control devices including heavy- duty limit switches, relays, manual controls and proximity switches. Other product lines are solid state keyboards for the computer industry and high-performance d.c. motors used in computer related equipment. So you can see that we are a component manufacturer. With the exception of the keyboards, every one of our products would "fit comfortably into a breadbox." Some are so tiny that one could easily fit several thousand into a man's hat. In my position as supervisor-packaging. package design, and materials handling engineering, I am actively involved in package design projects, parts handling design projects, and numerous activities involving departmental layouts, storage facilities, and material handling equipment. Two package design technicians, a materials handling engineer, and a materials handling technician make up the technical staff.

Jan 1, 1973

By J. Ye

A comprehensive flotation study has been carried out on a Chinese fluorspar ore using the packed flotation column developed at Michigan Technological University. The results are compared with that of a conventional mechanical flotation method on the same feedstocks. Key factors controlling flotation performance of both methods are evaluated based upon a simple statistic design. The flotation concentrate produced in one stage of the packed column has 4-S% higher recovery and much lower silica impurity content than that produced by up to six stages when a conventional mechanical cell is used. The results also show that the packed column flotation process is particularly suitable for recovery of finer fluorspar particles.

Jan 1, 1992

By David Yang

Commercially available flotation technologies for recovery of mineral fines have remained essentially unchanged for several decades. Recent studies have focused simply on improving mechanical and open column cells. Such studies have explored different control strategies and have aimed to improve reagent selectivity, fine air bubble generation and particle-air contact. However, no study has questioned whether current techniques are the most efficient technology for recovering mineral fines. Given that both mechanical and open column cells have a widely accepted carrying capacity limitation, the lack of extensive research into an alternative technology is surprising. Most recently, open column flotation has become an entrenched technology, and it is undermining the efficient recovery of mineral fines worldwide. An alternative exists. Packed column flotation overcomes the above-stated problems as the technology surpasses the carrying capacity limitation of current means by several-fold and almost always achieves the best performance in many comparative pilot tests and full-scale plant operations. Filling a column with packing plates creates a network of sloped walls capable of supporting a froth bed many times deeper than conventional machines. Having froth up to 75 percent of the total column volume tolerates all feed changes encountered in the plant environment and permits maximum flexibility in concentrate quality control. Furthermore, its scale-up is straightforward by increasing column volume or the number of interconnected small cells. As the air breaks upon rising and is distributed horizontally through packing plates, the air spargers can be replaced with a simple blower, resulting in considerable savings in operation and maintenance costs. Packed flotation technology provides a break-through solution for the separation of fine and ultra-fine minerals. Its simplicity, superior performance, and low cost structure make it an appealing alternative to current technologies and allow greater flexibility in downstream processing. Future industrial applications include a wide variety of metallic and non-metallic ores. This paper focuses on some recent scale-up campaigns for nickel and copper sulphide flotation applications compared directly to conventional equipment.

Jan 1, 2014

By Alessandro Martinis

The performance requirements for modern steelmaking facilities are ever more stringent, as customers and markets are continuously pushing for technologies which allow having high quality steel produced in an economic and sustainable way. In the details, this paper has the aim to present the excellent results obtained by integrated steel plant where an EAF is fed with high quality hot ENERGIRON DRI. The recent technology developments, combined with the affirmed basic process design, contributed to further maximize the energy of the DRI, reaching the EAF at temperatures above 600°C with a carbon content up to 3.5%, as confirmed by plant data. These improved input material characteristics resulted in reduced electrical energy consumption and increased liquid steel production.

Aug 16, 2017

By D. Royston

In SAG mills fed with a variety of ore types, hard packing between the shell lifters can come and go depending on rock type and rock size distribution and the presence of a binder. Packing can appear in all sizes of SAG mills, and can be tenacious. High ball impact forces (depending on ball size) in larger mills may compact and encourage packing. Packing can have a negative impact on milling performance and a change in shell liner design may be required to remove it. However shell liner design changes need to be managed with care to ensure liner reliability. In smaller mills control of packing can extend shell plate wear-life and may help to maintain milling performance in fixed-speed mills through the liner wear-cycle.

Jan 1, 2012

By Alessandro Martins Duarte, Gabriela Patrícia Gomes, Christiano de Paula Boaventura, Hélio Braz Loss, Janeir Ribeiro Dutra

Para produção de aço em uma usina integrada o gusa líquido é parte predominante na composição da carga metálica, porém, levando em consideração a sua composição típica e para otimização do processo é necessário que haja um tratamento precedente ao carregamento do convertedor. Teores elevados de silício carregados em convertedores para produção de aço carbono e elétricos provocam um maior consumo de fundentes para neutralizar a sílica gerada durante o processo e maior instabilidade, por outro lado teores muito baixo não fornecem um balanço térmico favorável para utilização de sucata. Diante disso é necessário trabalhar com uma faixa de silício que atenda o mínimo necessário para que se tenha um balanço térmico favorável. Este projeto teve por objetivo modelar a dessiliciação através da adição de um agente dessiliciante e sopro de oxigênio na panela, trabalhando com um teor de silício final entre 0,20% a 0,50 %. A dessiliciação do gusa é realizada em 2 etapas, sendo a primeira quando o gusa é transferido do carro torpedo para a panela e a segunda etapa com sopro de oxigênio. O projeto conseguiu reduzir em 44% a quantidade de corridas fora da especificação, reduzindo dessa forma o consumo de fundentes no convertedor.

Oct 1, 2019

By S J. Schafrik, E S. Gilliland, E C. Jong, J Waynert, C W. Weiss

Two commercially available through-the-Earth (TTE) communications systems were evaluated at an active underground longwall mine in West Virginia. One system utilises magnetic field (H-field) antennae while the other system utilises electric field (E-field) antennae to achieve communication. A large portion of this mine is overlain by an inactive gas-oil field composed of densely spaced wells. This feature provided a unique opportunity to determine the impact of cased wells on both TTE technologies. The following communication modes were investigated: surface to underground, underground to surface, underground to underground and real-time two-way communications. Standard deployments of the TTE systems using the manufacturer’s recommended procedures were able to achieve clear communications between underground and surface locations under certain circumstances. As a result, the design and deployment that will optimise TTE transmissions are unique to each system and to the specific area of the mine. This field study was conducted as a part of a larger multisite evaluation of available TTE systems in an effort to determine their operational sensitivity. The performance of these two TTE systems suggested that one may be preferable over the other depending on the conditions present during deployment.CITATION:Jong, E C, Schafrik, S J, Gilliland, E S, Weiss, C W and Waynert, J, 2015. Pairing magnetic and e-field through-the-Earth communication systems based on mine site conditions, in Proceedings Third International Future Mining Conference, pp 245–252 (The Australasian Institute of Mining and Metallurgy: Melbourne).

Nov 4, 2015

By J. P. Gliddon, G. C. Wade, J. W. Lill

Since 1980 a number of significant changes have been introduced at Palabora in an effort to offset the effects of reduced product price and increased unit costs of production. These changes and improvements include major equipment rationalization programs, the introduction of trolley-assisted truck haulage, adoption of a sophisticated computerized truck control system, pit design enhancements, improved drilling practices, use of emulsion explosives, and the installation of an in-pit crushing and conveying system. The various changes, their effect on the operation, and their contribution to cost reduction and improved productivity at Paihbora are considered.

Jan 1, 1987

By J. P. Gliddon

Since 1980 a number of significant changes have been introduced at Palabora in an effort to off-set the effects of reduced product price and increased unit cost of inputs. These changes and improvements include major equipment rationalization programs, the introduction of trolley assisted truck haulage, adoption of a sophisticated computerized truck control system, pit design enhancements, improved drilling practices, use of emulsion explosives and the installation of an in-pit crushing and conveying system. The various changes, their effect on the operation and their contribution to cost reduction and improved productivity at Palabora are considered.

Jan 1, 1987

By J. L. Robson, C. M. Bristow

mass flow rates of particles and air (the loading ratio).

Dec 1, 1994

By Wyborn L. A I, Idnurm M, Hinman M. C

Comparison of the Proterozoic Apparent Polar Wander Path (APWP) for Australia with the corresponding geology of northern Australia suggests that a number of discrete interplate tectonic events, manifested on the APWP as bends or inflections, may have controlled sedimentary basin evolution, ore fluid production and the timing of mineralisation. Similar features in the Phanerozoic APWP for the North American plate appear to correlate with major orogenic events, basin deformation, movement and 'entrapment' of hydrocarbons and minerals. Interplate tectonic events cause intraplate deformation which in turn controls the subsidence/uplift and sedimentation histories of the basins. Interplate events are thus responsible for creating, deforming and destroying sedimentary basins and the associated petroleum and mineral systems. The basins of northern Australia show remarkable similarities in the successions of volcanic and sedimentary deposits. Unconforrnities of regional or sometimes only local extent have been mapped between the major sedimentary sequences and it is predicted that interplate tectonic events corresponding to bends or inflections on the APWP directly reflect the processes that have produced these widespread unconformities. These processes are also likely to have controlled the geometry and character of the fluid migration pathways and hence the mineralising events. Palaeomagnetic studies of Proterozoic rocks in sedimentary basins provide a tool for predicting the timing of regional mineralisation events, particularly for low-temperature mineral systems. The techniques, when coupled with systematic regional basin analysis, using petroleum exploration techniques, may identify a number of new mineral 'plays' in northern Australia. Prominent inflections in the APWP occur at approximately 1700, 1670, 1650, 1600, 1540, and 1480 Ma. Each of these may be related to a regional compressional deformation, important mineralising event, or significant change in style and type of sedimentation. Most appear to be associated with magnetic overprints. Some of the inflections between 1400 and 540 Ma may also mark significant events in the evolution of Meso- and Neoproterozoic basins. Further work is required to correlate inflections in the APWP with alteration events in order to understand their regional significance.

Jan 1, 1994

In order to appreciate fully the place of palaeontology within the general framework of the geological sciences, consideration must be given to the time, about 150 years ago, just before the study of fossils was beginning to be applied to geological problems. At theend of the eighteenth century, almost all geologists recognised that fossils were the remains of animals and plants that had lived at the time when the rocks in which they occur were formed. It was also realized that many-some geologists thought all-rocks hadbeen formed under water, but as regards the order of succession in which these rocks had originated, and the relative ages of rocks found in different parts of the world or even of one country, only the haziest and most contradictory ideas existed.Around the turn from the eighteenth to the nineteenth century, a widely taught system of theories was that of the German professor, Abraham Gottlob Werner, who believed that the surface of the earth had once been covered by a universal ocean at whose bottom all rocks had been deposited. As the level of this ocean gradually subsided, older rocks-so Werner taught-are now generally found in the mountains or at great depth below the younger rocks; this was his "Primitive Division" which included granite, gneiss, schists, slates, basalt, porphyry and other igneous and metamorphic rocks, all of which he believed to be of sedimentary origin. Younger rocks, according to Werner, were formed at successively lower levels as the water receded. Next in age he placed a "Transition System" of limestones and greywackes; still younger the so-called "Floetz Division," which included sandstone, limestone, gypsum, salt, coal, but also some basalt, porphyry and other rocks; youngest were the alluvial deposits of recent clays, loams, sands and gravel. Thus, in the Wernerian system the age of a rock was determined on the basis of its petrographic properties and the height of its occurrence relative to sea-level.Here and there these ideas survived well into the nineteenth century. As late as 1825, Charles Darwin listened to lectures by Professor Jamieson, one of the last proponents of Wernerian theories in England. The fact that entirely different kinds of fossils occurredin rocks which were regarded as contemporaneous did not worry the theoreticians.It is, therefore, noteworthy and significant that the value of fossils for the interpretation of geological events was demonstrated to the geologists by an engineer and surveyor, WiIIiam Smith, who, although no professional geologist, has often been called the "Father of English Geology." His professional work, which was mainly concerned with drainage and irrigation projects, took Smith to all parts of England, where he sometimes journeyed as much as 10,000 miles in 11 year. Smith was a keen observer and, unhampered by theoretical speculations, he noted the occurrence of fossils and collected specimens wherever he went. Before long he realized that the same kind of fossils followed each other in successive layers of rocks in much the same way in different parts of England, and soon he was able, by looking at fossils collected by other people, to tell from what...

Jan 1, 1950

By Irina A. Pulyaeva

Hydrogenetic Fe-Mn crusts play an important role in marine mineral-deposit research because of their widespread occurrence and high concentrations of valuable and rare metals. Most Fe-Mn crust deposits occur on the tens of thousands of seamounts found in the global ocean as well as on ridges and plateaus. Because of these circumstances, it is essential to clarify a number of outstanding issues with regard to Fe-Mn crust history and development, including controls on metal sources and concentrations. The first-order characteristics of Fe-Mn crusts as potential ore deposits include concentrations of metals (grade) and the thickness of crusts (tonnage), which vary depending on Fe-Mn crust structure and texture. Data on the structure, composition, age, and deposit characteristics will help define which factors are key for the creation of mineral accumulation and which combination of factors leads to the formation of potentially economic concentrations of metals. In this paper, we address the structure and characteristics of Fe-Mn crust stratigraphic sections collected from Central and Western Pacific seamounts. We describe the changes in mineralogical and chemical compositions of crust layers of different ages, the occurrence and regional distribution of these layers that correlate regionally, and reconstruct the paleoceanographic conditions that influenced crust growth.

Jan 1, 2010

By James A. Martin

Evaluation and subsequent development of a quarry in east-central Missouri was based on a general but brief examination of outcrops and core from five (5) test holes. Neither core, outcrops, nor existing quarries in the general area gave any indication of potential major problems. In the third year of operation large areas of collapse rubble, consisting of green shale and large blocks of limestone and sandstone, were encountered. Their size and random distribution resulted in both blasting and quality control problems. By the fourth year of operation, production costs became prohibitive and the site was abandoned. Prior to dismantling the plant a geologic investigation, which included shallow seismic and resistivity surveys, was made of the unmined portion of the lease. The collapse dolines appear to be related to structure and predate development of the modern topography. Surface indications of these features are few. The seismic profiles were especially helpful in plotting their distribution. Geologic relationships and seismic data developed at this site are being related to similar suspect areas in Missouri and have been useful in their evaluation.

Jan 1, 1970

By W. Mueller, M. Rocheleau, E. Dimroth

The paleogeographic evolution of the Abitibi Belt is subdivided into three phases, namely: 1) a phase of the growth of a submarine volcanic chain, 2) a phase of the emergence and growth of volcanic islands and 3) a phase of uplif t and erosion of volcanic islands. Isostatic calculations suggest that the volcanic sequence in the south of the Abitibi Belt rests on oceanic basement or on the mantle; the volcanic sequence in the north of the belt rests on about 13-14 km of tonalitic basement. 10-15 km of plutonic material accreted to the volcanic islands during paleogeographic phases 1 and 2, and caused the uplif t during paleogeographic phase 3.

Jan 1, 1984