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By B. D. Nichols, W. S. Gregory

SOLA-DM is a three-dimensional finite-difference computer code designed to model the dynamics of an incompressible fluid and the transport of discrete particulate material around obstacles impervious to flow. The numerical methods used in this code are described. SOLA-DM was used to predict the particle flux sampled by the 10-mm Dorr-Oliver Cyclone and MINIRAM dust monitors. Various geometric and dynamic variations of monitor and airflow combinations were tested. The code predictions are shown in computer-generated graphic plots.

Jan 1, 1987

By Stafford McKnight, Larissa Koroznikova, Steve Hall, Cameron Klutke

This paper outlines a simple methodology for mineral characterisation, developed as part of the Australian Mineral Industry Research Association (AMIRA) managed research project P777 ?The Development of Heavy Suspension Techniques for High Density Separations (Replacement of Clerici?s Solution)?. The project was sponsored by De Beers, Rio Tinto and Iluka Resources. Heavy mineral characterisation of samples arising from exploration, mining or metallurgical processes is frequently conducted using laboratory heavy liquid analysis. Unfortunately, there are only a limited number of high density (?heavy?) liquids and these tend to be more toxic as their density increases. Low-toxicity inorganic solutions, based on tungsten compounds, have been developed that can be utilised at relative densities (RD) up to 3.0. Beyond this value organic liquids can be used, however this presents significant health and safety hazards. Diiodomethane (methylene iodide) having a relative density of 3.31 is commonly used. Mixtures of thallium formate and thallium malonate were found in the early 1900?s by Clerici to provide liquids having specific gravities between 4.0 and 5.0. For the characterisation of the heavy components of mineral sand deposits (e.g. anatase RD 3.9, rutile RD 4.2, ilmenite RD 4.4 ? 4.7 and zircon RD 4.6 ? 4.8) there is currently no heavy liquid alternative to Clerici?s solution. Clerici?s solution is highly toxic and testing is now conducted by few laboratories worldwide with costs reflecting the chemical costs, infrastructure costs and health and safety regimes (e.g. blood testing of exposed staff). A simple laboratory technique of density fractionation has been developed, employing suspensions of fine tungsten carbide particles in lithium heteropolytungstates solutions, that can replace Clerici?s solution in the evaluation of fine mineral sands samples (e.g. -250 +150 microns). The developing methodology that can achieve low-cost, low toxic separations at relative densities above 4.0 is outlined and the comparison of results with Clerici?s solution presented. In addition, preliminary work on density fractionation of zircon samples is presented. Zircon fractionation relates to their inclusion, radionuclide content and metamictization.

Jan 1, 2007

By J. Ludden

By Sims Some two years ago we began investigating low coke button bituminous coal for use at our Bound Brook, New Jersey plant as a replacement for anthracite. Since August, 1957 the plant has been operating continously on this coal with the exception of a new 200,000#/hr, cyclone boiler. This study was motivated not from our desire to conduct combustion research, but for the sole purpose of reducing our steam costs, The indications were that the economics were greatly in favor of the use of the bituminous coal. The attempts to reduce the costs have developed some knowledge that has enabled this program to succeed reasonably well as will be discussed later by Mr. Ludden. The production of steam size anthracite is dependent upon either the reclamation of old culm banks or the breakage in the production of the domestic sizes. The anthracite industry has not as yet been able to cut, its mining costs to the point where the production of steam sizes has become a profitable business. This has resulted in two basic problems: (1) A constantly rising price in an attempt to have those sizes carry their share of the cost and, (2) Periodic shortages of supply when the demand is good but the market price prohibits the mining of anthracite to produce those sizes only, These conditions have made the long range forecast appear as though the price would go even higher and/or the supply at times be critically short.

Jan 1, 1958

By T. R. Roy

A prediction model, developed by Central Mining Research Institute (India) for evaluation of fire risk rating of underground coal mine panels in bord and pillar working in respect of their proneness to spontaneous heating, is presented in this paper. The concept used in this model is innovative and user friendly. This model may be applied to a panel where extraction is carried out using any of the techniques: i) depillaring with formation of small pillars as final operation, ii) extraction by broadening of galleries, iii) depillaring with hydraulic sand stowing, and iv) depillaring with caving. Here, major fire risk parameters are short-listed and divided into three broad groups in accordance with the nature of their contribution to the spontaneous heating of a mine panel. The paper describes the procedure for estimating the fire risk rating of individual groups using separate objective type models developed for this purpose. Then it evaluates the overall fire risk rating of the panel by combining the fire risk ratings of all the three broad groups. The model is tested with the field data collected from different collieries spreading across the country and with the laboratory data for critical assessment of fitness. Keywords : prediction model, fire risk rating of panel, spontaneous heating of coal, underground panel, bord and pillar working.

Jan 1, 2003

By W. M. Myers

[Utilization of small stone is recognized as one of the important problems of the lime industry. The term ?small stone' is used to designate material that is too small for calcination in tie shaft kilo. The maximum dimension A such stone rosy be placed at four inches. The introduction of any considerable quantity of stone having demensions lee: than this into the charge of a kiln impedes the draft and readers successful operation of the kiln difficult on impossible. Attempts design a shaft kiln which would calcine stall stone satisfactorily have not been successful to date. Thousands of tons of this small stone arc produced daily, and while part of it finds a market, for it has many uses, the profit is usually small an competition is teen and prices are low. Production of the material is, however, so greatly in excess of market that surplus of hundreds or possibly thousands of Jose axe place daily in stock piles and classified as waste. in a few instances a fortunate combination of circumstances, such as a program of or other work requiring large quantities of concrete aggregate, may mate it possible some quarries to market this stone later at a profit, teat in general the chances A profitable utilization are slight, and the quarry operator has the expense of handling this waste stone and providing a storage site for it. The brittle nature of limestone makes it impossible to quarry the stone and crush, it to size suitable for the shaft kilns without producing an excess of undesirable fines. Elimination of fines by changes in quarrying or crushing practices cannot lee expected. On the contrary, the adoption of more modern methods of quarrying in recent years has increased the proportion of small material. The tendency is to blast the roan with large charges of explosives and crush it with mechanical crushers, which produces more fines than the older methods of careful blasting with small char yes and sledging the rock by hand.. We increasing use of underground mining of limestone has also increased the production of small stone, as blasting in the confined space of an underground stope shatters the rocs more completely than quarrying in the open. The use of the very friable limestones, such as the limestone of Florida for the manufacture of lime adds a new factor to the calcination of small stone. These friable lime limestones have a low tensile strength and crumble in the kiln, causing trouble. Successful calcination of these stones is accomplished in specially]

Jan 1, 1926

By M. Zaki El-Sabban

Tables of chemical thermodynamic properties for the ideal gas state from 0° to 1,000° K are reported for eight alkanethiols, three cycloalkanethiols and arylthiols, six thiaalkanes, two dithiaalkanes, three thiacycloalkanes, and three thiophenes. They are based on current physical and thermochemical constants and definitions, reliable vibrational assignments, and the latest insights into molecular structure and energetics.

Jan 1, 1970

By B. Ladanyi

The design philosophies for piles in unfrozen and frozen soils are compared, and their similarities and differences are underlined. It is shown that in frozen soils, the long term behavior of a pile is difficult to predict, because of inadequate knowledge on the behavior of adfreeze bond with time, and on the value and variation of the lateral normal stress acting on the pile. Both of these problems are discussed in the paper on the basis of laboratory tests and theoretical analyses.

Jan 1, 2010

By R. Ricketts, D. G. Vanderveer, F. Kirby

"A program of mapping, sampling and testing to determine the potential of the aggregate resources throughout Newfoundland and Labrador was commenced in 1978. A 6-km-wide corridor parallel to all transportation routes was selected as the study area.The study consisted of a preliminary surficial interpretation followed by field mapping and sampling. Granular resources were sampled at a 500-m interval and non-granular materials were sampled at a 1.5- to 2-km interval. Data were gathered on landforms and stratigraphy as well as a field description of the sample and deposit types. Particle-size and lithologic analyses of the samples were also conducted.The locations of samples and deposits were mapped on 1:50,000 topographic base maps and summarized for publication at a 1:250,000 scale. Surficial geology maps were produced at a 1:50,000 scale. A computer program is being developed for the search and retrieval of field data.The first phase of the Inventory of Aggregate Resources program is nearing completion and to date has collected information on approximately 9,500 samples throughout Newfoundland and Labrador. This data will be used to provide f or the effective management of these vital non-renewable aggregate resources.The mineral aggregate industry in Newfoundland and Labrador is very competitive, but undercapitalized when compared to other provinces. The demand for aggregates is forecasted to increase to in excess of23 million tons per annum by the year 2002.In terms of over-all mineral production, the extraction of sand, gravel and stone has a significant impact when compared to other minerals in terms of value and tonnage produced.IntroductionThe province of Newfoundland has approximately 18,000 km of coastline. A large proportion of the population lives in coastal communities where, traditionally, beaches have been a major source of construction materials. Beaches have, therefore, often been subjected to overutilization, resulting in erosion of back beach areas or adjacent headlands."

Jan 1, 1982

By Emad Farouz

This paper compares the predicted axial capacity of driven Pre-cast Pre-stressed Concrete (PPC) piles for the Lake Gaston Water Treatment Plant (LGWTP) using several design methodologies versus the axial capacity measured from dynamic and static load testing. The LGWTP site is located in Chesapeake, Virginia and is part of the Great Dismal Swamp. The subsurface investigation included soil borings, in-situ dilatometer (DMT) tests, and in-situ piezocone (CPTu) tests. The axial capacity predictions of the PPC piles were performed using the computer programs DRIVEN and FB-DEEP which are based on SPT N-values. Additionally, an empirical method proposed by Martin, et al. (1987) based on local experience with PPC pile design in the Yorktown formation in the Tidewater area of Virginia was also evaluated. Finally, the ?Laboratoire Central des Ponts et Chausées (LCPC)? method developed by Bustamante and Gianeselli (1982) based on CPT measurements was also used to develop the axial pile capacity of the piles. This paper shows that the FB-DEEP computer program and the LCPC method provided a reasonably good prediction of the pile axial capacity measured from PDA, CAPWAP, and Static Load Tests in comparison with the other design methods used. The soils in this area develop significant setup over time and it was found that FB-DEEP and the LCPC method are capable of incorporating this setup in the prediction of the long-term axial capacity of driven piles in this area.

Jan 1, 2007

By Kenneth E. Merklin

The heavy media process is now being used extensively throughout the world for the gravity concentration of a great number of different minerals. The process is a commercial adaptation of the heavy liquid procedure which has been used in laboratories for many years to separate mineral of different specific gravities. In the heavy media process, a suspension of finely divided particles in water is used to increase the apparent specific weight of the fluid to the desired separating point. The original heavy media process used sand, galena, pyrite and occasionally other materials as the solid constituent of the separating suspensions. As the process developed, the need for a more universal media meeting the following requirements was recognized: 1. High specific gravity. 2. Resistance to abrasion. 3. Resistance to corrosion, 4. Readily reduced to a suitable size consist for suspension in water. 5. Available in quantity at economical price levels. 6. Easy to recover by a simple method.

Jan 1, 1958

By L. M. . Chia

The successful treatment of waste materials to recover metals with acceptable purity is often hampered by the presence of undesirable impurities. The problem is further complicated by the need to insure that any residues or solutions generated are environmentally acceptable. Hydrometallurgical processes involving leaching- solvent extraction-electrowinning offer some attractive features which address many of these problems. However, in certain instances trace impurities that contaminate the organics are difficult to chemically strip and interfere with the overall process efficiency. A new processing scheme has been developed which appears to provide some attractive alternatives for impurity removal from organics. It has been shown that many ionic impurities can be electrochemically removed from the organic by spontaneous direct reduction using solid metals. A variety of metal ion impurities have been removed from selected common organic extractants such as D2EHPA and TBP using different metals as the reducing agents. The results and probable mechanisms involved in the reactions are discussed.

Jan 1, 1994

By Lester Uren

The fluid level maintained in wells pumped for oil is an important factor in deter-mining their productivity but one that has received little attention in the literature relating to petroleum-production technology. In the present paper the writer undertakes to show how and to what extent fluid level influences productivity and suggests the use of a fluid level indicator as an aid to the oil producer in maintaining the fluid surface within the well at the proper position. IT is realized that the depth of fluid maintained in a pumping well is sometimes influenced by other considerations than the quantity of fluid that will enter the well: the prevention of sand incursion, prevention of waste of natural gas, and the maintenance of a suitable submergence for the pump, for example. These latter factors have an important influence on the productivity of the well, so that otherwise unwarranted fluid levels must sometimes be maintained to offset them; but where the handling of unconsolidated sands is not a problem of consequence and where water has been properly excluded, the principles developed here and the practices recommended, should apply. The principal objective of the producer should be to produce the maximum quantity of oil in the shortest possible time. Any method or equipment that will increase the rate of production during the early years of the life of the well, when gas pressure is high, will greatly augment the .ultimate production. The maintenance of a proper fluid level in the well at all times will go far toward accomplishing this desired result. For a given set of conditions surrounding the flow of oil into a particular well, in which the viscosity of the oil, the porosity and grain size, of the sand, and the diameter of the well appear as constants, two variables determine the quantity of oil that will flow from the sand into the well. These are: the effective pressure behind or within the oil in the reservoir sand, and the fluid level maintained within the well.. The former is the expulsive force that causes movement of oil from the sand into the well, while the latter determines the magnitude of a resisting force opposing such movement. The first of these factors is largely beyond the control of the oil producer, but it is in his interest to reduce the opposing force to the lowest economic limit.

Jan 2, 1925

By Hong-wei Ma

With social development and technological advancement, mine rescue robots used in complex environments have developed as a research hotspot. This paper reviews the progress of research on coal mine rescue robots, and key technologies of rescue robot design are put forward, such as mechanical structure, self-navigation and self-orientation, multi-sensor information fusion, multi-robot cooperation, and wireless communication technology.

Aug 1, 2013

Iowa Geological Survey, Des Momes, Ia. George F. Kay, State Geologist A list of publications will be sent upon request Most of the papers of the Survey have been published in the Annual Reports, issued since 1892. Separates of the many papers in the Reports may be had for postage, except where they are out of print, and except for vol 1 (1892), 2 (1894) and 14 (1903), where no separates are to be had. Thirty-five Annual Reports have been issued up to and including vol 35 (1929). A charge, plus postage, is made for vols, 4, 5, 7, 8, 9, 10, 28 and 33, others will be sent free upon request, plus postage on from 2 to 6 pounds Space prohibits giving more than a general picture of some of the contents; vols 4, 5, 7, 8, 9, 10, 11, 12, 13, 15, 16, 20, 27, 32, contain, among others, papers on the geology of Iowa, by counties Vol. 19 (1908), 6 lb , contains a number of papers dealing with the peats and coals of Iowa, and has bibliographies of those subjects Vol 22 (1912), 6 lb , contains an annotated bibliography of Iowa geology Vol-24 (1913), 6 lb , contains the analyses of 16 Iowa coals Vol 28 (1917, 1918), price $1 50, 4 lb , completely covers the subject of gypsum in Iowa, and has a bibliography of the sub¬ject. Each volume carries an administrative report and a review of mineral production for the period covered In addition, Technical Paper 2 (1930), Studies of Iowa coals, will be sent free upon request Also a geological map of Iowa, and maps of Iowa showing the distribution of the glacial drift sheets throughout the state, have been issued and are available

Jan 1, 1933

By Hugh Steele, Brower Dellinger

U. S. mining trends for 1956 continued steadily U+ S. uphill, technique and equipment advanced with the pull, and exploration and development of once mined districts attracted more attention than new areas. Expansion of the Ambrosia Lake district in New Mexico more than doubled known uranium ore reserves, and production began from several of the large new ore discoveries. In Canada the up trend was more spectacular, especially in exploration and development. To combat increasing problems arising from high labor costs, taxes, low grade orebodies, and dwindling discoveries, manufacturers and mining companies have continued to introduce new techniques and new products-reamer bits for enlarging small holes drilled by jacklegs, whup d'whups for drift mucking, Cryderman machines and over-the-head small crawler-type machines for shaft mucking, the 20-ton TL 220 four-wheeled tractor trailer unit for underground haulage, inertia-type dust collectors, roof bolting in conjunction with chain link fencing for wall support, wooden roof bolting using compression support of ground for wall support, and new one-use carbide bits.

Jan 2, 1957

By Dan W. Bench

PCBs are hazardous not only to human health and the environment but also to the mining industry because of potential worker exposure and improper disposal liabilities. In this sense, the paper point out the identification, management, and proper disposal of pcb-containing electrical equipment used in mines. Also it point out alternatives to PCB dielectrics, storage, and disposal. The use of PCBs in mines has been documented during U.S. Environmental Protection Agency Region 8 mine inspections and it used as dielectrics in transformers, capacitors, and fluorescent light ballasts are common throughout industry worldwide.

Sep 14, 2009

By Carol A. Pilon

"IntroductionRECENTLY, the Saskatchewan Research Council (Saskatoon ) marked the completion of one of its coal-related projects with the publication of the Bibliography and Index of Coal in Saskatchewan and Adjoining Provinces and States, hereafter referred to as the Bibliography and Index of Coal. Over a two-year time period, literature was surveyed and indexed and bibliographic data were compiled using a computer-assisted information retrieval system called FAMULUS. The final publication contains 1150 bibliographic references, which are cross-referenced by six indices.The project was initiated in September 1974, in support of Saskatchewan's Coal Resources Evaluation Program , an ongoing research program sponsored by the Department of Energy, Mines and Resources (Ottawa) and the Province of Saskatchewan. This program places emphasis on such areas of concern as the occurrence of deposits, chemical and physical properties, calculation of reserves and computer-assisted applications for the evaluation of lignite resources in the Province. Attention is also given to aspects of geophysical exploration, mining conditions and economics, by-products and the transporting of lignite. These are the subject areas .covered by the Bibliography and Index of Coal.The over -all objectives of the literature indexing project may be enumerated as follows: (1) to build a specialized resource library by surveying established public and specialized libraries, and commercial data bases; (2) to enter library data into the FAMULUS information retrieval system, to be used to generate bibliographies and indexes, and to retrieve information by the use of specified searching techniques; (3) to make this library data available to interested persons."

Jan 1, 1977

By B S. S Rao, S Chandra

IndiaÆs iron ore mining industry is growing rapidly in order to augment the capacity to meet the unprecedented demand for the iron ore. Traditionally, much of Indian iron ore production came from exploitation of high-grade haematite ores, with the exception of Kudremukh which beneficiates lean grade Banded Magnetite Quartz ore. Now with the changed scenario of demand and supply, keeping long term sustainability in mind, it is imperative to develop suitable processing technology for exploitation of banded haematite quartz (BHQ) ore available abundantly and not utilised so far. In this direction detailed characterisation and beneficiation studies were conducted with BHQ iron ore from the Bellary-Hospet region of India, assaying 36.5 per cent Fe. The mineralogical studies with the image analyser system revealed the presence of maghemite and haematite as iron-bearing minerals. The gangue mineral associations were siliceous, ferro-magnesian and carbonate minerals. Higher degrees of liberation were observed in the size range of 75 - 212 microns. Liberation grind tests were performed by grinding the ore to different top sizes in a closed circuit laboratory ball mill with the ground samples subjected to Davis tube tests. The yield, grade and recovery were used as parameters to plan a two-stage wet drum magnetic separation based on grinding the primary magnetic concentrate. After subjecting the final magnetic concentrate to flotation to remove residual silica a concentrate assaying more than 68 per cent was obtained. The non-magnetic product from the primary magnetic separation was deslimed, ground, blended with secondary magnetic tails and was subjected to a two pass wet high intensity magnetic separation (WHIMS). The WHIMS concentrate was further subjected to two-stage flotation to remove residual silica to obtain concentrates assaying 64 - 66 per cent Fe. The final combined concentrate from wet drum magnet and WHIMS after flotation could yield a blast furnace (BF) grade pellet feed concentrate assaying more than 65 per cent Fe with a yield about 39 per cent and iron recovery about 70 per cent. A direct reduction (DR) grade pellet feed concentrate assaying 67 per cent Fe with a yield of about 28 - 31 per cent and iron recovery about 53 - 57 per cent could also be produced. Based on the test work, a process flow sheet was developed to beneficiate the BHQ ore for production of BF/DR grade pellet feed concentrate. In this paper methodology adopted for selection of individual process, various diagnostic tests performed to rule out other beneficiation processes and the final process flow sheet development is presented and discussed in detail.

Jan 1, 2007

By Robert Trueman

This paper details the results of an assessment aimed at understanding the shield loading mechanisms associated with strata-related issues on a longwall face. Shield load cycle analysis theories developed by the authors were used to quantify the interaction between the shields and strata. Shield pressure data was back-analyzed using a version of the Longwall Visual Analysis (LVA) software that has been extended to enable efficient load cycle analysis to be undertaken. The software outputs enabled the shield strata interactions to be characterized. The results of the analyses indicated that the major cause of the roof falls was high-level periodic weighting, resulting in periodic shield overload. Exploration borehole data was analysed to identify and characterize the overburden unit that was the likely cause of the shield overloading.

Jan 1, 2011

By Harry J. Olson

Geothermal Energy has a great potential for meeting the electrical and thermal energy requirements of many countries and territories lying along tectonically active zones within and surrounding the Pacific Basin. Energy requirements for many of these small, scattered volcanic island nations preclude development of conventional generating facilities large enough to incorporate any economies of scale. However, by attempting to discover and develop shallow, relatively low temperature, geothermal reservoirs associated with recent vulcanism on many of the volcanic islands, exploration expenditures and risks, and problems associated with the development of high temperature resources can be reduced. Exploration and development drilling for these resources can be accomplished with truck mounted rotary drilling rigs that are less costly and more suitable for operations within the island infrastructures than the conventional rigs normally used in the drilling of deep, high temperature geothermal resources. Experience over the past decade with small, modular, binary (Rankine) cycle generating units indicates that geothermal energy can provide a reliable source of baseload electricity in the amounts required and at a cost that is competitive with other alternative and conventional energy sources. Development of shall, moderate temperature, geothermal resources with small, modular binary cycle generating units can provide ideal additions to the energy sources of many of the Pacific volcanic island nations within the framework of their island economies.

Jan 1, 1991