Search Documents

[Separates of all the Technical Publications published in 1929 are available at lnstitute headquarters. All the papers are on file in public, university and technical libraries, and when so indicated in the list, may be found in the Transactions.] Metal Mining Technical Pdbli- Title Author Meeting Trans. cation . Volume No. and Page* 182-A-23 The Royal Commission on Mining Henry Louis New York Subsidence Feb., 1929 183-A-24 Cycles in Metal Production D. F. Hewett Nen. York T29, 65, 95 Feb., 1929 199-A-25 Ventilation at the United Verde Oscar A. Glaeser New York T29,- 114. Mine Feb., 1929 206-A-26 Air Conditioning In Deep Mines R. W. Waterfill New York T29. 99, 112 Feb., 1929 245-A-27 Bumps in No. 2 Mine, Springhill, Walter Herd New York Nova Scotia (with discussion) Feb., 1929 257-A-28 Misfires: Their Causes, Prevention New York and Treatment on Occurrence Feb., 1929 Misfires in Anthracite Coa1 T. D. Thomas Mines (With Discussion) Misfires in Bituminous Coal W. H. Forbes Mines (With Discussion) Misfires in Non-metallic Mining A. W. Worthington (Limestone) (With Discussion) Milling and Concentration 195-B-15 A Study of Differential Flotation C. R. Ince New York Feb., 1929 196-B-16 Elements of Operation of the Arthur F. Taggart New York Pneumatic Table H. L. Lechmereoertel Feb., 1929 202-B-18 Silver-bearing Minerals of Some A; W. Habn New York T29, 325 Ores from Tintic Mining District Feb., 1929 204-B-17 Experiments with Flotation Re- A. F. Taggart New York agents T. C. Taylor Feb., 1929 C. R. Ince 208-B-20 Cyanide Regeneration or Recov- C. W. Lawr Sun Francisco ety as Practiced by the Com- Oct., 1929 pania Beneficiadora de Pachuca, Mexico 214-B-19 Calculations in Ore Dressing W. Luyken New York E. Bierbraer Feb., 1929 217-B-21 Differential Grinding Applied to Leon M. Banks San Francisco Tailing Retreatment George A. Johnson Oct., 1929 224-B-22 Reducing and Oxidizing Agents Research Staff San Francisco and Lime Consumption in Flo- of United Verde Oct., 1929 tation Pulp Copper Co. 247-B-23 Copper Sulfate as Flotation Acti- 0. C. Ralaton San Francisco vator for Sphalerite 0. R. King Oct., 1929 F. X. Tartaron

Jan 1, 1929

By F. A. Rutledge, J. J. Mulligan, W. H. Kems, R. L. Thome

"As a part of the United States Department of the Interior program for the development and use of Alaska raw materials, the Bureau of Mines is conducting an investigation of deposits f nonmetallic minerals accessible to the Alaska Railroad for use in building materials in the Alaska Railroad-belt area. The results of the investigations, to date, indicate that raw materials for the production of brick products are in plentiful supply as clay in the Anchorage area, as fire clay at Sheep Mountain, and as shale in the Healy Creek coal formations near Healy, Alaska.Shale for the production of lightweight aggregate or Haydite occurs near mile 67 on the Glenn Highway, and preliminary tests give excellent results. Physical tests are new in progress on commercial-size concrete building units made with this aggregate. Another shale deposit in the same formation was located at mile 16 on the Matanuska Branch of the Alaska Railroad, and preliminary tests give comparable results.Natural lightweight aggregate in tree form of pumice and pumicite occurs in Katmai National Monument and has been used with excellent results in lightweight-building units in Anchorage and Fairbanks. These deposits will be investigated in more detail by the Bureau of Mines during 1952.One small perlite deposit near Healy, Alaska, showed excellent expanding properties, and the product compares favorably with commercial perlites being used in the States for plaster and concrete aggregates. Additional investigation by the Bureau of Mines to delimit the known occurrence and, if possible, discover others were planned for the 1951 field season.The pumice from Katmai National Monument also was considered for use as a pozzolan in pozzolan-portland concrete. Tests by the Bureau of Reclamation indicate that the pumice sample submitted by the Bureau of Mines would be satisfactory in strength development but is not outstanding. Natural activity is good and is greatly improved by calcination at 1,4000 F. Water requirements and shrinkage also are satisfactory. However, the material is ineffective in reducing expansion owing to alkali-aggregate reaction; and, if reactive aggregate is used to make concrete, it would not insure against excessive expansion. An attempt will, be made during the 1952 field season to delimit pumicite deposits along the Alaska Peninsula more amenable for use in pozzolan-portIand concrete.Because the Railroad belt has such a rigorous climate, insulation for new construction is of prime importance. Luring the Bureau of Mines, investigation of building materials all samples were submitted for chemical analyses as possible sources of raw materials for the production of rock wool, one of the best insulation mediums. Four areas having deposits of the required constitu¬ents were located as follows: Anchorage area, with Potter limestone and argillite; Cantwell-Windy area, with limestone and shale; West Fork of the Chulitna River area, with limestone and agrillite; and Homer-Seldoyla area, with Seldovia limestone and Homer clay. It was planned to take bulk samples of these formations and submit them for testing during the 1951 field season."

Mar 1, 1953

"IntroductionThe combined library facilities of the five universities in the Generic Technology Center for Respirable Dust, The Pennsylvania State University, West Virginia University, University of Minnesota, Massachusetts Institute of Technology, and Michigan Technological University, represent one of the most extensive and comprehensive collections of information on respirable dust research which is available in the United States. The Center encompasses two major medical schools, the Milton S. Hershey Medical Center at The Pennsylvania State University and .West Virginia University Hospital at West Virginia University, and includes national and international experts from such diverse disciplines as geology, geomechanics, mining engineering, mineral processing, electrical engineering, industrial engineering, mechanical engineering, material science, physics and several areas of medicine. In order to maximize achievements in research and facilitate early results application in the private industry, university, government and public sectors, a geographically dispersed Reference Center on Respirable Dust has been established at each of the affiliated universities. This network serves to encourage unity between the universities in the Center and coordination and communication with other entities who benefit from their research.Description of the Reference CenterIn this light, the goal of the Reference Center network is to identify at what location Information is available and to provide a means for others to access this information. It is especially necessary to have both ease of input and maximum retrieval capabilities available to all the research personnel in the Reference Center. At the same time, the service provided to the inquiring public must be complete and cost-effective. The Center's approach to realizing this goal incorporates advances in computerized and electronic searching of individual library holdings and the networking of major library and commercial search systems.The Reference Center uses the following means to achieve this goal. At each participating university, a hard copy collection ls maintained of the current respirable dust research in progress by that institution's personnel. Also, available. at each university ls a review of their past and present research on respirable dust. At each participating university a hard copy collection of annual status reports and of all publications produced by Center personnel for symposiums, national and international conferences ls maintained. A key word computer search capability ls available to participating universities. This computer search, by title, author and location, allows researchers to determine at which facility information is available, thus avoiding the tremendous expense and effort of housing all the information on respirable dust research under one roof. The Reference Center has access, through The Pennsylvania State University Libraries system and the libraries of other institutions, to a large number of data bases such as MEDLINE at the National Library of Medicine,"

Aug 31, 1989

By R. N. Johnson

This report is a summary of the work performed for the Bureau of Mines to evaluate the feasibility and desirability of a movable in-pit crusher combined with conveyors to substantially reduce or eliminate truck or train haulage in large open-pit non-fuel mineral mines. The report includes an introduction and summary of previous work, an analysis of movable crusher system components, a description of the selected system, a review of possible movable crusher system applications, and finally requirements for future work to bring about the general availability of such systems. It was clear from the program that there is a real need for movable in-pit crushers.

Jan 1, 1982

By S Thomas, E Grimsey

Mining education in Australia has undergone another cyclical downturn over the past five years and several departments have been discontinued while others are still teetering on the brink of destruction. During this downturn Curtin UniversityÆs WA School of Mines (WASM) has managed to stay alive and well, but this has not been by accident. This paper outlines some of the strategies and experiences that have kept WASM in a strong position and offers hope to other departments and schools elsewhere that are still experiencing difficulty. This paper is also directed at all mining departments and schools that are certainly going to see it all happen again after the next mining boom turns to bust.

Jan 1, 2004

By Clinton C. Knox

To demonstrate the feasibility of unwatering ore reserves previously indicated in the virgin Melrose zinc-lead field in Kansas and Oklahoma, the Bureau of Mines .carried through a pumping project on the Park Walton farm in 1943. Due to success of the undertaking, attention was turned to exploration of other indicated ore deposits and promising areas within that part of the field benefited by .the drainage project, By the middle of 1946, four private mining companies were active in the field; and a considerable output of lead and zinc concentrate had been obtained from the new Park Walton mine and mill. The Park Walton Ore deposit was unwatered by installing deep-well pumps in three holes previously drilled by the lessee. Pumping was continued by the Bureau of Mines at a rate of 2,500 to 1,000 g.p.m. for about 6 months; during this time the local static artesian water-level, originally averaging 108 feet below the surface in the old drill holes was lowered to the 316-foot level, which justified beginning the initial shaft sinking and mine developments. In all, about 750,000,000 gallons of water was pumped by the Bureau of Mines at an operating cost averaging $0.024 per 1,000 gallons.

Jan 1, 1948

By B. McHenry, A. E. Wraith, P. J. Mackey

The Wallaroo smelter on the Yorke Peninsula, South Australia commenced smelting operations in 1861 treating ores from the nearby Moonta and Kadina mines. The plant expanded and modernized on several occasions and was a leader in the successful introduction of new technology to improve operations. It operated continuously until 1923 when local mines became exhausted; in the closing stages of the 19th century it was the largest copper smelter in the world outside of those in Swansea, Wales. In 1892 a small electrolytic refinery was established at Wallaroo, the first in Australia, based on principles developed by Elkington at Pembrey, Wales in 1869. The Wallaroo refinery was specifically built to recover gold and silver from copper produced by smelting gold-containing feed materials shipped from Western Australia. This first venture into electrolytic refining was replaced in 1903 by a somewhat larger refinery which, although modest in size for its time, with a capacity of about 1000 tonnes of cathode copper per year, was very productive in precious metals. Anode copper was produced by an updated version of the reverberatory-based Welsh process until 1910 when barrel-type pneumatic converters were introduced based on American practice; subsequently, anodes were cast by tapping the precious-metals rich "bottoms" portion of converter copper as produced at about one-fifth into the copper blow. The present paper describes the Wallaroo refinery, its anode supply and products, supported by initial observations on a sample of a Wallaroo cathode held in the collection of the South Australia Museum, Adelaide SA, Australia. INTRODUCTION Australia ranked 6th in the world for copper mine production in 2018, with an output of 918,000 tonnes of mined copper, after Chile, Peru, Congo, China and the USA; about 40% of Australian mined copper was smelted in the country. Interestingly, the world ranking of Australia in mined copper has, with a few variations, remained about the same for more than 100 years – of interest, it was also the 6th largest country for copper production at 21,089 tonnes in 1899. At that time, all or most of the copper was smelted in the country (Mackey, 2016). Copper was first discovered in Australia in 1842 in South Australia not far from Adelaide; additional copper discoveries in the region soon followed. At first, copper ore was shipped to Swansea, Wales for smelting (Bampton, 2003). However, in addition to the long, 150 day one-way sea passage, it seems Welsh smelters preferred higher grade of ores – these aspects and likely a mood in the new colony to be independent of Swansea (Evans, 2014) evidently encouraged local smelting at the mine sites using small, Welsh-type reverberatory furnaces fired with hardwood as fuel and operated by Welsh and Cornish migrants. The first large copper smelter in Australia commenced in 1848 at Bremer, near Callington some 60 km east of Adelaide. With larger discoveries on Yorke Peninsula, the Wallaroo copper smelter at Wallaroo Bay on the west coast of the peninsula commenced operations in 1861 (Bell & McCarthy, 2008). Thus began one of the most successful, and in its day, one of the most advanced and innovative plants in Australia if not the world. In the late 1860s, it was considered one of the largest copper smelters in the world (Bell & McCarthy, 2008)

Jan 1, 2019

By Helen D. Robinson

Traditional practice to resist large lateral loads on foundations is the use of large diameter caissons, battered driven piles, or battered micropiles. Dense urban construction environments, however, limit the usefulness of these systems due to the close proximity of below- and above-grade obstructions. This paper presents two micropile construction projects in the United States where a complex scheme of battered micropiles and grade beams was developed to counteract large lateral loads at the foundation level. The paper also presents a procedure used to design vertical micropiles for large lateral loads, which can greatly simplify the design of foundations subject to significant lateral loads in urban environments. A design example shows a case where vertical micropiles were used to support allowable design lateral loads greater than 80 kip per micropile.

Jan 1, 2010

By Thiago Rangel Bittencourt

Com a tendência de aumento da complexidade geométrica dos painéis de cobertura dos automóveis, aumento de resistência mecânica e diminuição da espessura dos materiais, a estampagem dessas peças tem tornado cada vez mais difícil. Neste contexto, dois graus de aços que exibem elevada resistência mecânica e boa conformabilidade, têm sido ofertados pela siderurgia à indústria automotiva, o Bake Hardenable (BH) e o Interstitial Free High Strength Steel (IFHSS). O presente estudo teve como objetivo avaliar aços BH e IFHSS, em termos de propriedades mecânicas, de conformabilidade, de ganho de resistência em função da deformação, envelhecimento e de resistência à indentação, em escala laboratorial. Desse modo, visou-se avaliar sob quais condições de estampagem deve ser decidido o uso do BH ou do IFHSS em aplicações de painéis automotivos. Os aços avaliados, de um modo geral, apresentaram desempenho similar em termos de conformabilidade. O aço BH foi superior ao IFHSS em relação à resistência à indentação. Portanto, o aço BH aparece como uma solução técnica atrativa, comparativamente ao aço IFHSS, quando aplicado em painéis externos (capôs, portas e paralamas) que requerem maior exigência quanto à resistência à indentação.

Aug 7, 2018

By L Edwards, M Haest, D Mittrup

The focus in the iron ore industry has shifted from increasing production volumes with less regard for cost, to efficient production of quality tonnes. BHP Billiton iron ore geoscience and exploration has embedded infrared spectroscopic sensing of drill hole samples to help meet this challenge.Infrared spectroscopy is delivering mineral predictions that are used for (automated) geology logging and modelling. The spectra are processed together with other available data sets to predict geometallurgical and geotechnical variables that include lump per cent and uniaxial compressive strength.Trials are ongoing to test the benefit of infrared spectroscopy during mining, including the analysis of grade control samples and remote sensing of mine faces. Results show great benefits in the fields of short-term geology modelling, better understanding of material (handling) properties, identification of geotechnical risk areas and high resolution ore-waste delineation.These trials are bringing BHP Billiton iron ore closer to its ultimate goal of having infrared spectroscopic data collected across the mining value chain. Once such data are available everywhere, regression models can be trained at one point (eg iron grade model trained on exploration samples) and be applied elsewhere (eg iron grade predicted on mine faces). Such predictive analytics will enable not only high precision mining, but also provide maximum time to tailor plant design to the ore in the ground, based on learnings from ores processed in other plants. This will improve planning outputs that will eventually increase mining efficiency, processing capability and product quality.CITATION:Haest, M, Mittrup, D and Edwards, L, 2017. Infrared spectroscopy in BHP Billiton iron ore with a focus on in-mine infrared sensing, in Proceedings Iron Ore 2017, pp 549–556 (The Australasian Institute of Mining and Metallurgy: Melbourne).

Jul 24, 2017

By Kenneth Eilerts, Vincent Smith

"INTRODUCTION Knowledge of the Phase relations of fluids produced from combination wells 4/ at the pressures and temperatures characteristic of production from natural reservoirs is essential to efficient recovery and refining practice. An accurate sample of the fluid from such wells may be prepared by mixing (in the proportions of the measured gas:liquid ratio) gas and liquid taken from the separator conditions of steady flow; and physical properties of the sample, at significant pressures and temperatures, may be determined with suitable laboratory apparatus for use in the solution of engineering problems. The results of study of sample so obtained and of mixtures of gas and liquid from the separator combined in other proportions are presented in this report. Attention was given in the study to the relationship between the physical properties of what may be regarded as the constituent materials - the gas and liquid taken from the separator - and the properties of mixtures of these constituents. Data obtained for the complete range of mixture Proportions are expected to provide a reference scale for the study of other combination-well fluids produced at different liquid:gas ratios."

Apr 1, 1942

By J. W. Thompson

ESTATE IN MINERALS. Minerals beneath the surface may be made the subject of separate ownership either by a grant of the minerals by the owner of the land or by a grant of the land excepting the minerals, and thereby an estate in fee simple is created in the minerals, as corporeal things real. Colby, In re, Iowa, 169 Northwestern 443, p. 444. DEEDS EXCHANGING DIFFERENT MINERALS-RIGHTS OF PARTIES. The lands of two adjoining owners were underlaid with cement rock and clay at a depth of about 100 feet from the surface and with coal veins some 600 feet below the surface. By an exchange of deeds one of the land owners conveyed to the other the cement rock and clay with the right to mine and remove the same without entering upon the surface, but the deed contained no covenant not to injure the surface. The other deed conveyed the coal seam and so much of the rock and other minerals just above and below the coal as might be required in connection with the mining and removing of the coal, together with the right to mine and remove the same, and the adja- cent rock, clay, and other minerals, without entering upon or injuring the surface, with one immaterial exception. The deeds do not define the word "surface" and neither expressly nor by implication did they secure to the coal owner the right to subside the overlying cement rock; but the implication is to the contrary, as the deed gives the right to mine and remove coal without entering upon or injuring the surface. The provision that the coal owner should not enter upon or injure the surface amounts to a clause that the coal mine. shall not be worked so as to let down the surface and this does not create any inconsistency with the provision giving the right to mine and carry away the coal.

Jan 1, 1919

By Mayo D. Hersey

This problem was taken up by the Bureau of Mines as a result of the oxygen explosion at the Jefferson Physical Laboratory of Harvard University , and other similar explosions , in order to supply technical information which would serve as a basis for safety precautions in the future . At the Harvard inquiry the fact was emphasized by the Massachusetts State Chemist , Mr. Walter M. Wedger , that we do not know the limiting pressures and temperatures above which compressed oxygen and lubricating oil are capable of spontaneous explosion . The problem is also of importance to the Army and Navy and to the Bureau of Mines in connection with the hazards incurred in the use of compressed and liquified gases in the repurification of helium. In fact , the risk of fires and explosions due to traces of lubricating oil coming into contact with high pressure oxygen is of serious interest to all concerned with the manufacture and use of oxygen , a commodity which is now being produced and distributed on a rapidly increasing scale . Part of the money expended on this investigation was from Army and Navy funds . The problem was undertaken by the Bureau of Mines at the suggestion of Dr. Charles E. Munroe , Chairman of the Committee on Explosives Investigations of the National Research Council , and referred to the Pittsburgh experiment station of the bureau.

Jul 1, 1923

By Roger C. Malan

The Monument Valley and White Canyon districts are in northeastern Arizona and southeastern Utah. Exploration and mining for uranium has been conducted in these districts since the late 1940's. In July 1965, ore reserves plus ore production at 174 properties were approximately 3.3 million tons of ore containing about 19 million pounds U3O8, of which about 10 per cent remained in reserves. The two largest mines, Monument No. 2 and Happy Jack, together account for about 45 per cent of the sum of production and reserves. Approximately half the deposits in these districts contain less than 1000 tons of ore. Nearly 5000 feet of Permian, Triassic, and Jurassic sedimentary rocks, mainly continental in origin, are exposed in these districts. All the important uranium deposits are in the Shinarump, the basal member of the Chinle Formation of Triassic age. The Shinarump lies on a widespread unconformity. It is composed of fluvial sediments, generally less than 100 feet thick, that were deposited by streams flowing from a source to the south. Most of the deposits are in an arcuate belt, convex to the west. This belt, 3 to 12 miles wide, extends from Monument Valley northward nearly 130 miles. It is along the western flank of the ancient Monument Valley-Monticello upland, an area that was slightly uplifted at the beginning and again at the end of deposition of the Shinarump. Erosion and subsequent reworking of the Shinarump sediments in the vicinity of this upland are postulated to have made possible the transportation, in solution, of the uranium contained in these sediments. The soluble uranium probably was carried by migrating ground water into sites favorable for precipitation in Shinarump beds bordering the upland. Thus, the original very small amounts of dispersed uranium in the early Shinarump sediments were accreted in the favorable belt where the accumulations of carbonaceous plant remains and their decay products provided a persistent reducing environment.

Jan 1, 1968

By G. W. Center

This manual is intended to assist federal, state, and local regulatory and planning agencies, the mining industry and consulting engineers in determining the regulatory, environmental, technical and economic constraints influencing the site selection, planning, construction/operation and reclamation phases of a waste disposal facility. The information presented illustrates that factors affecting an individual site may be simple or very complex. This manual discusses methods for making future land use decisions, determining regulatory requirements, evaluating physical, chemical and structural properties of the disposed waste and selecting appropriate waste disposal methods and control techniques. Procedures and guides in the manual will assist personnel in assessing the complexities of waste disposal on a site specific basis. The major types of waste disposal systems are discussed and evaluated in terms of their advantages and disadvantages and applicability to varying site conditions and waste characteristics. Appropriate references following each chapter provide more detailed data on material presented in the text.

Jan 1, 1982

By J. H. Adkins

The goal of the project reported in this paper was to make recommendations for changes in roof bolting procedures and bolter design that would reduce roof bolter accident rates. To that end the project identified the major hazards associated with each task a roof bolter operator per-forms, normalized task accident frequencies. by the time spent on each task, reviewed equipment design features and operating procedures related to the identified hazards and developed recommendations for equipment and procedural changes that would reduce, if not eliminate, the hazards. The research steps completed during the project were: a. A review of related literature and re-search including roof bolting time studies b. The collection and analysis of 1975 accident data pertaining to roof bolter activities c. The normalization of the accident frequency data on the basis of time/task data d. A review of roof bolting equipment e. The development of a field data collection instrument f. The selection of mines for bolter observations g. The collection of field data h. Data analysis and problem specification i. The development of recommendations for corrective measures

Jan 1, 1978

By J. A. Herbst

A state of the art computer simulation package, named UTAH-MODSIM is being developed. This package can run on a mainframe (eg. UNIVAC) as well as on a microcomputer (eg. IBM/PC with at least 512 kBytes of core memory). Friendliness was the major concern in developing this software. The user simply generates a complete flowsheet by presenting the flowsheet on a graphics terminal. This flowsheet defines the circuit to be simulated. With the minimum required data, the user can obtain a complete mass and water balances within a few minutes. Moreover, this package will provide scale-up and capital cost information of specified equipment relevant to design. In order to illustrate the utility of this software, three design examples are given. They are: a) A typical multistage crushing plant. b) A reverse closed grinding circuit comparing one stage with two stage classification. c) A standard closed grinding circuit suitable to liberate a specified fraction of chalcopyrite from a copper ore.

Jan 1, 1986

By Ronald B. Stotelmeyer

This report summarizes studies of 55 Idaho national forest roadless areas completed by the U.S. Bureau of Mines (USBM) in the period 1966-1992. These roadless areas have been recommended for addition to the National Wilderness Preservation System, proposed as special management areas, or otherwise recommended for study by the U.S. Forest Service or the Idaho congressional delegation. The Bureau of Mines' studies indicate which parts of the roadless areas contain mineral resources. They also show where mining and prospecting are likely to occur in the future, where mineral production has occurred in the past, and where abandoned mine workings (possible hazards) would be encountered. The number of mine and prospect workings found are a measure not only of surface disturbance, but of areas not wilderness in character.

Jan 1, 1994

A major highlight of Fiscal Year 1993 is the completion of a new research facility dedicated to the advancement of robotics research and development. This new facility brings to the U.S. Bureau of Mines one of the largest and most unique facilities of its kind in the world. Located at the Bureau's Pittsburgh Research Center, the facility consolidates under one roof, all of the resource requirements of a first class automation and robotics research program. The Mining Robotics Development Center (MRDC) is the result of a major renovation of a large under-utilized warehouse-type structure and brings together the laboratories and offices previously housed in five separate buildings scattered throughout the Pittsburgh Research Center's 238-acre site. This new facility will support the computer-assisted mining research program, a high priority, multi-million dollar program that is expected to have a high impact on the health and safety of miners and coal productivity.

Jan 1, 1993

Australian coals tend to be young in geological age and high in ash by world standards; preparation of the coal before marketing is almost universal. On the basis of float and sink data from 39 locations in the Eastern Australian coalfields, the coals are placed in four categories representing increasing difliculty in their washability characteristics. These seem to be related neither to the geological age nor the geographical position of the deposit and Hunter Valley coals, for example, span all categories. The influence of crushing on the washability of Australian coals is briefly considered and from limited data it is concluded to be appreciably smaller than for British or North American coals. A strategy for the float and sink analysis of Australian coals is proposed and the influence of washability characteristics on current trends in the selection of separating processes for coking and steaming products is discussed.

Jan 1, 1979