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By Petre Stelian Nita

In small steelmaking shops, in foundries and forging plants, there are not too many option to recycle the basic slags, which are not suitable for many purposes of recycling, because of their low chemical and structural stability. A solution of an adequate recycling is a direct recycling in EAF. Several quality requirements, physico-chemical properties and proportions of slags must be analysed. The progress in this fields permites to establish an adequate proportion of recycled slag, based on enough exact computation of the related property. For oxydizing slag, obtained during melting and in the first part of decarburization operation, the problem of phosphoms contents can be analysed using the phosphate capacity (C PO34-). For reducing periods, during deoxidization operation, desulphurization also occurs and the problem of the sulphur contents can be analysed using the sulphur and sulphide capacities ( Cs / Cs) Between this two complex thermodynamic indicators of the slags. a direct relation is established, using thermodynamic aspects, resulting from the equilibrium constants for dephosphorization and desulphurization process and also, using the optical basicity of slags, computable from the chemical analysis of the slags. On this basis starting from the steel quality requirements. adequate strategies can be established in order to obtain high rates of recycling (between 50-80%) of steelmaking slags. Important cost savings are obtained through this procedure, based on the correct amounts of the fresh lime, iron ore and fluidizers. Keywords: Slag, Properties, Recycling

Jan 1, 2003

By BLAllEY STEVENS

(Canal Zone Meeting, November, 1910.) I. INTRODUCTION. TEH object of this paper is to show how igneous intrusion is governed by definite mechanical laws. A distinction is made between dikes and fissures, and the various characteristics of intrusions are explained on an exact scientific basis. The modification of rock-stresses by intrusion is then considered and extensive isostress regions are recognized. Finally, a complete classification of intrusions is constructed covering all pos-sible cases. The generalizations of observed data, taken from Geikie's Textbook of Geology, conform to the laws of intrusion herein stated, and the deductions based upon these laws. No authority, however, is quoted for the type which I have named a corrugated intrusion. Its existence is a necessary deduction from the laws of intrusion, and even the entire absence of examples in technical publications cannot disprove its reality. In all probability, corrugated fissures would have remained undiscovered, but for the working of mineral veins. As intrusions of tabular form are seldom worked for commercial purposes, it has been left for theory to anticipate the discovery of corrugated dikes. In the light of these laws of intrusion and the corresponding laws of fissures,1 there seems to be a remarkable uniformity of stress-distribution in rocks at moderate depths. This renders .possible the mathematical calculation which should help us to approximate exact science in this and kindred branches of applied geology.

Jan 1, 1911

By William H. Engelleitner

Agglomeration by balling in cylindrical or shallow pan devices dates back to the early part of this century. The first sintering tests conducted by Dwight-Lloyd on nonferrous ores included a mixing step for ore, flux and fuel carried out in a deep pan device similar to the balling pans, or discs, presently in use. Further work directed mainly toward sintering of ferrous and nonferrous ores always included a preparatory step, usually referred to as mixing, agglomerating or green-balling of the ingredients. In the late forties and early fifties two methods of particle preparation prior to firing were in general use. In Europe the balling pan was used predominantly, both as a mixer and as a pelletizer. In the United States many pilot plants and semi¬commercial plants used balling drums. When the first iron ore pelletizing plants were built in this country, the most frequently used device for green-balling was the cylindrical drum. At the same time, the pan device was used both in Europe and the United States for many other materials such as fertilizer, cement, flyash, alumina and copper concentrates, as well as to mix the feed for sinter machines. The difference between these two balling devices - -the drum and the disc - has been the subject of much discussion and is well covered by several papers included in the 1962 publication "Agglomeration' issued by AIMS, based on their 1961 International Symposium held in Philadelphia. (1)

Jan 1, 1965

By Theo Lehner

"During my first contact with industrial metallurgy as a summer vacation worker at the Steelplant at Luleå, Sweden, I came during a visit to MEFOS into contact with works of Prof. Worner caried out during the piloting of the Worcra continuous steelmaking process. These tests are still today remarkable as an innovative step in the art of metalmaking. By that they involved the necessary ingredients for the development of our art: seeing, knowing and doing. Industrial injection as applied during slag fuming will be discussed below.Phenomena of injection metallurgyPhenomenon according to Collins dictionary is"" anything that can be perceived as an occurrence or facts by the senses"". To open the senses for the interesting phenomena in pyrometallurgy must be the main task of any educator. The investigations by Engh et al. around the mixing phenomena of the WORCRA process are an early example of combining senses with knowledge. To see what you model must be a crucial part in any development. This can also involve to see and control that one is subject to the same conditions as in published models. Below the need ""to see"" will be illustrated by some recent investigations around slag fuming. In the literature various models for reactions occuring during the fuming of slags are presented. Two recent models hint ·ata) the occurrence and importance of iron for the fuming processb) the occurrence and importance of lead droplets during respectively."

Jan 1, 1996

By D. Cantali

This paper will be presented in two parts. The first part will present the latest advancements in pile installation techniques using state-of-the-art press-in piling technology by Giken. By pressing in sheet piles and large modulus contiguous steel tube pile walls – as opposed to the more traditional installation methods using percussive hammers or vibrators – retaining structures can be constructed effectively noise and vibration free. For over water and coastal projects with limited access, this provides significant environmental benefits in the form of minimising the construction foot print and the impact to surrounding communities and the marine natural habitat. Typical noise and vibration data will also be presented. The second part of this paper will review the current manufacturing techniques for sheet piles and introduce innovative new materials used in the current piling market for embedded sheet pile walls. Materials include long service life non – ferrous materials such as new age plastics and fibre reinforced polymer piles. Their excellent long term performance and durability make them an effective solution in the marine environment. For steel piles, a number of steel grades with reduced corrosion characteristics will also be discussed including a newly developed steel to combat corrossion in the low water zone, an area often exhibiting the highest moments in a retaining wall. A number of project case studies will also be presented to reinforce their relevance in today’s changing construction landscape.

Nov 1, 2022

By Vedala Sastry

Longwall mining for coal extraction in deeper deposits is gaining momentum in India, due to the increasing stripping ratios and depletion of shallow deposits amenable for surface mining. In longwall mining, presence of multiple seams with varying interburden thickness is a major problem especially while planning for over-mining. An investigation program was taken up to analyze the effect of the presence of goaf and virgin coal blocks in already developed and extracted lower seam by bord and pillar mining, on the stress distribution in the longwall panel in upper seam. Studies revealed marginal increase in horizontal and shear stress as longwall face passes above goaf to the virgin area present in lower seam. Stress distribution over chock shields was considerably affected when the face in upper seam reached 15-25m zone above the galleries in the lower seam. A clear influence of the presence of solid coal, galleries and goaf in lower seam was found in the loading of longwall panel in upper seam.

Jan 1, 2007

By Crazy Horse - The Journal of Explosives Engineering - Vol 20 No 1

The crew at Crazy Horse Memorial has produced a w o n d e rful new video called “The Fine Art of Mountain Carving.” The video closely examines for the first time, the extraordinary explosives engineering on the Crazy Horse mountain currently in pro g ress in the Black Hills of South Dakota. The 56-minute video takes the viewer up the mountain for a behind-the-scenes look at the drilling and blasting crew at work on the mountain. The video was written, edited and produced by Robb D e Wall and is available exclusively from the Crazy Horse Memorial in both DVD and VHS formats. For i n f o rmation, see www.crazyhorsememorial.org The following, is a brief summary of the 25 steps involved in carving the mountain. The video goes into extensive detail on each of the 25 steps. Both those in the explosives industry and those outside the industry will find the video intere s t i n g .

Jan 1, 2004

By Chas. Kohl

ABOUT 1929 an engineer was engaged to organize a Safety Department, lay out an educational program, and achieve a reduction in accident frequency. Due to the large number of employees, about 12,000, and the distances between the various properties, it was a big undertaking. Most of the workmen are from the Sierra and for generations have been agricultural people, with little conception of modern tools and machinery, and to a large degree are illiterate. However, gratifying results have been obtained, as evidenced by the accident frequency curve during the sixteen-year period. Safety offices have been established in each of the six major properties, staffed by men who devote their entire efforts to inspections of working conditions and equipment, instructions as to safe methods, and investigations of accidents. The Corporation is a member of the Inter-American Safety Council, receiving their publications and literature, which serve to keep us up to date and informed on modern methods. Dissemination of this material is accomplished chiefly through word-of-mouth and bulletin boards. When it is found that the accident rate is increasing in a certain occupation, as for instance underground haulage or mine hoisting, the operators so engaged are assembled and given renewed instructions on the safety code pertaining to their work. Inter-camp competitions in accident avoidance are being conducted, with annual awards for that unit having the lowest severity rate for the year.

Jan 1, 1945

By G. Mousavian, R. Bagheri, N. Dalili

Polypropylene (PP) and its composites have an increasing use in automobile and domestic industries. Since the published results on strain rate effect on yield behavior do not match, and there is a high attention paid for effect of nanometeric fillers on deformation behavior of composites, in this research the strain rate effect on yield behavior of PP and the effect of nanometeric fillers on deformation behavior of PP have been studied. Microscopic observations and tensile tests in different strain rates on neat PP samples and on samples filled with 5, 10 and 15 %wt have been used. A dramatic change in behavior for the modulus and post-yield slope curves when the strain rate is between 0.0433-0.05 s-1 has been observed. Microscopic observations on PP indicate a change in deformation mechanism from shear yield to crazing at the same strain rate that the change in behavior of curves occurs. It has been observed that in PP nanocomposites with higher amount of calcium carbonate, fracture in early stages of deformation occurs in lower strain rates. In other words for a fixed stain rate there is a critical filler percentage such that if the filler percentage is higher then early-stage fracture will occur. Similarly for a fixed filler percentage there is a critical strain rate and in higher strain rates early fracture will occur. The critical stain rate will decrease as the filler percentage increases and vice versa.

Jan 1, 2006

By A. Yörükoglu

In this study, thorium mineral that found in the complex ore deposit bearing bastnasite, fluorite, and barite from Eskisehir - Sivrihisar district has been tried to extract by using HCl and H2SO4 leaching. Ore sample of approximately 3 tons taken from the ore deposit has been homogenized in order to obtain composite samples by means of ore preparation techniques for experiments. Results of chemical analyses of composite samples are as given; 40.8% CaF2, 35.35% BaSO4, 2.01 Ce, 1.5% La, 0.39% and 0.1% Th. HCl and H2SO4 leaching processes have been performed to gain Th in the ore. For determining the optimum particle size, the samples have been ground under controlled conditions and brought to the sizes of 0.065, 0.2, 1 and 3 mm. Leaching experiments have been carried out in both HCl and H2SO4 acids without roasting and roasting at the temperature of 900°C for 1, 3 and 6 h retention times for all particle sizes determined before. In the experiments, the highest Th recoveries reached are as follows; 78.74% Th when H2SO4 and 1 mm particle sized sample used, and 1 h roasting applied and 73.38% Th when HCl and 1 mm particle sized sample used, and 3 h roasting applied. Keywords: thorium, leaching, concentration, sivrihisar, roasting

Sep 1, 2012

By Theodore H. Budd, Douglas J. Heinz

This report concerns the successful construction of Contract No. 287 of the Northeast Side Relief Sewer System for the Metropolitan Sewerage District of the County of Milwaukee. The contract involved the construction of approximately 3316 meters (10,880 feet) of tunnel concrete lined to 1.83 meters (72 inch) internal diameter; 30.48 meters (100 feet) of 1.83 meters (72 inch) reinforced concrete pipe jacked-in-place; a river crossing of approximately 107 meters (350 feet); 197 meters (647 feet) of 1.83 meters (72 inch) reinforced concrete pipe in open-cut; several diversion and flow monitoring structures; and miscellaneous manholes and appurtenances. The contract proposal, which was extremely prescriptive, did allow alternative methods of primary support consisting of precast reinforced concrete segments, steel liner plates, steel ribs with wood lagging, and combinations thereof in designated areas. The specifications required the contractor to designate which support scheme it intended to use. The specifications also required compressed air as a means of ground water control for approximately 2316 meters (7600 feet) of tunnel. The alternative selected in the bid proposal was the support method consisting of steel ribs and wood lagging for 2263 meters (7425 feet) of tunnel and steel liner plates for the remaining section. Shaft supports, by specification, were designed to be steel liner plate with steel ribs varying in size from 4.27 meters to 6.10 meters (14 foot O.D. to 20 foot O.D. ).

Jan 1, 1983

By James R. Hein

Manganese nodules from the Cook Islands (CI) Exclusive Economic Zone (EEZ) are compositionally different from other nodule fields. CI nodules have relatively high cobalt concentrations and low nickel, copper, and manganese concentrations (e.g. Hein and Petersen, 2013). This reflects the predominantly hydrogenetic (seawater source) origin for metals in the CI nodules versus dual seawater-pore water sources for most other nodules. The concentrations of many critical and strategic metals have not been previously analyzed for CI nodules, so comparisons with other nodule fields have been limited. To address this, we analyzed a set of nodules distributed throughout the CI EEZ for a complete set of 67 elements, including all of the metals that may be of economic interest, such as the rare earth elements (REEs), yttrium, tellurium, niobium, zirconium, tungsten, titanium, and others (see selected elements in Table 1). In addition, we recalculated the tonnages of nodules and contained metals from nodule abundance areas (in square kilometers) determined by GIS ArcMap calculations based on JICA/MMAJ (2001) nodule distributions. The nodule tonnage calculated and summed from each abundance sector yields a total inferred resource estimate of 9.66 billion tonnes of nodules covering an area of 1.21 million square kilometers; using a cut-off of 6 kilograms of nodules per square meter, yields a median tonnage of 8.59 billion tonnes of nodules covering 687,647 square kilometers (Table 2).

Sep 14, 2011

By AIME

PROBABLY no greater world traveler has ever been Chairman of one of the Institute's Divisions than Henry Frederick Hebley. To begin with, he was born almost as far away as possible-in Christchurch, New Zealand, Dec. 15, 1893. There he grew up, studying mechanical engineering at the local Seddon Memorial Technical College. Then he went over to Sydney, Australia, for a bit of work before sailing for the U.S.A. in 1915. After a few months as draftsman in a San Francisco office he moved over to Clarkdale, Ariz., in the engineering department of the United Verde copper smelter, which had just gone into operation. But the war was on, and Henry thought he belonged in France with the Canadian Engineers, the United States still remaining aloof from the conflict, and that was the last the copper industry saw of him. After almost two years in France he was wounded, convalesced in England and Canada, and then went back to his native New Zealand to design concrete factory buildings. But soon the United States called again, and this time he landed in Salt Lake City with the Oregon Short Line R.R. Co. Then to Chicago in 1920. where he really got into the coal industry for good, working for the Allen K Garcia Co. on the design and operation of coal mines, beneficiation plants, and combustion equipment; and joining the Institute.

Jan 1, 1946

By A. W. Ambrose

"Records of individual wells form the basis for the successful operation of any company engaged in the production of petroleum. The expense attached to the compilation of records is negligible in comparison with the benefits resulting from their use. There a company has not a complete system of records, immediate attention should be given to the preparation of forms upon which to collect data, and, to the collection of data for these forms. The records needed vary with each district, but for each field a set should be adopted that will best meet the needs of each property. Practically all operators, and particularly all successful operators, agree on the necessity of good records, shopping what the wells have done, are doing, and may be expected to do in the future. Any operator realizes the value of records of sales of oil and should place almost equal emphasis on the records of well logs and histories showing the east and present performances of wells. Indeed, trustworthy records are absolutely necessary for the proper operation of any oil or gas property.Complete records should be kept on each well from the time the location and elevation are determined until the well is abandoned, and the engineer should review old records often enough to be familiar with the past performance of the various wells and with the conditions that affect production. Some of the forms that may be prepared are:--"

Mar 1, 1920

The kinetic and practical aspects of the extraction of copper from copper-rich solutions by cementation on iron was investigated. Tests were made on the effect of stirring speed, cupric sulphate concentration, acid concentration, temperature, and ferric sulphate concentration on the reaction rate and excess iron consumption.Most kinetic investigations were conducted under a nitrogen atmosphere to prevent any oxidation of the iron or copper metals. The stirring mechanism for all tests incorporated the use of a rotating impeller above a static disc in the solution. The activation energy for cementation on the steel disc at high stirring speed was 8·6 kcal/mole, indicating a predominant chemical control.Increasing the pH first decreased, then above pH 3, increased the reaction rate. Additions of sodium sulphate also significantly increased the reaction rate.The use of high temperature and high pH under an inert atmosphere has been suggested for increasing the reaction rate and producing a high purity sponge copper product.

Jan 1, 1972

By W. G. Robinson

"MINING is one of Canada's most important industries and exploration is the life-blood of this dynamic and exciting business. The health and growth of the mining industry of tomorrow depends on the effort and thought that go into exploration today. The Members of the Geology Division of the C.I.M. are directly concerned with exploration, and it is fitting that this Division should periodically sponsor reviews of the thoughts and practices of the exploration com-munity. Accordingly, we have invited seven leading authorities to contribute papers dealing with specialized aspects of this field.Exploration is a science, or art if you will, that is constantly changing in keeping with our expanding knowledge of geology and technology. It started with the old-time prospectors who searched the wilds for exposures of ore, and made finds that developed into some of our most important mining camps. As more discoveries were made, they were able to relate certain types of deposits with particular geological conditions, laying the foundation for modern concepts of economic geology. The mapping by the early field parties lacked detail and usually served to outline the ""greenstone"" areas considered favourable for prospecting. More de-tailed studies through the years by government and company geologists led to new thoughts on the origin, emplacement and geological control of orebodies. The continuing diversity of opinion on these subjects indicates a need for further research, but each year sees an increase in our reserves of factual information."

Jan 1, 1967

By W. J. Wenger

Oil fields in the Powder River Basin of Wyoming have produced 731 million barrels of petroleum through 1959. Production in 1959 was 32 million barrels, the highest production since 1924. The record production was in 1923, when the Basin produced 38 million barrels of oil and the Salt Creek field, then at its peak, produced 35 million barrels. In this report, the characteristics of crude oils found in the Basin are used as a basis for determining the best re-fining uses for the oils and for predicting the characteristics of oils that may be discovered in the Basin in the future. Analyses of 108 oils sampled over a period of 30 years are presented Crude oils of two major types are produced from the Powder River Basin. One has a low sulfur content and occurs in younger formations, and the other has a high sulfur content and occurs in older formations. The oils with low sulfur contents are generally light colored and waxy, and may be either paraffinic or naphthenic. The oils with high sulfur contents are usually dark colored and asphaltic; only their low boiling fractions are paraffinic. Alteration appears to account for the anomalous properties of some oils found at shallow depths. Shapes and slopes of correlation index curves classify the oils into the same two groups as their sulfur contents, with gently sloping curves representing the low-sulfur oils and steep curves representing high-sulfur, asphaltic oils,

Jan 1, 1961

By Sheldon P. Wimpfen

EVERYWHERE in mining circles the talk is of this new development of hard faced or insert bits which hints of many changes to come in mining practice and rock drill equipment. In the past fifteen years new equipment has appeared in rapid succession which brought one change after another in rock breaking practice. Detachable bits were an innovation which met with wide success. Blasthole diamond drilling has proven itself. Only recently, fusion piercing was announced as a possible solution to the problem of breaking taconite ores. For several years this interest in new methods has been growing and various experimental usages of tungsten carbides in rotary type rock drilling bits have been partially successful. American experts in rock drilling have been concerned with the subject for ten years but actual commercial practice was begun by European manufacturers and mining companies. At this time nearly every manufacturer of rock drilling bits is working on some type of an insert bit. On the Rand, European manufacturers are testing out various types of insert bits. The problems relating to rock drilling in South Africa vary greatly from ours. The bulk of the drilling there is limited to the 31/2-ft holes that are drilled for breaking the gold bearing reef ore. Rock drilling in most mines is far more diversified. Both drifting and ore breaking call for holes varying in length from 4 ft up to as much as 50 ft and more.

Jan 1, 1947

By W. Petruk

An investigation was conducted to determine the minimum number of samples that must be studied by image analysis of polished sections in order to characterize a mill product and to determine the apparent mineral liberation. It was found that a representive polished section cannot be prepared from an unscreened sample that has a wide size range of particles. Similarly individual screened' fractions are not representative of the sample because minerals are partitioned during screening. Consequently the quantities of soft brittle minerals are increased in fine grained fractions and quantities of hard minerals are increased in coarse grained fractions. It is assumed that results obtained by combining data for a series of narrow size range screened fractions (1 Tyler size range) are representative of the sample, and relatively accurate apparent mineral liberation data can be obtained for a mill product by analysing each fraction and combining the data. Somewhat less accurate data would be obtained by analysing a series of screened, fractions that have a wider size range of particles (5 Tyler size ranges). Mineral liberation analyses show that the most reliable apparent mineral liberation in each screened fraction is a value taken from a smooth curve drawn through the lowest points on a graph of % free vs size. A correlation between the apparent mineral liberation in screened fractions and calculated mineral liberations using Kings liberation model is good for sphalerite but not for chalcopyrite and galena.

Jan 1, 1985

R. H. Sweetser, Sault Ste. Marie, Ont. (communication to the Secretary*):—The recent work of furnace No. 1 of The Algoma Steel .Co., at Sault Ste. Marie, Ontario, using for fuel, first all charcoal, then a mixture of charcoal and coke, and finally all coke, upsets the estimates given by Mr. Hall in the last two paragraphs of his interesting paper. Furnace No. 1 was built for a charcoal-furnace, and it was run on charcoal fuel from March 6 until July 9, 1905; then, for a week, a mixture of charcoal and coke was used, and, since then, coke alone has been the only fuel. It is to be regretted that at no time, during the run on charcoal, was there enough charcoal on hand and " in sight" to warrant blowing the furnace as hard as it should have been blown. During April and May the supply of charcoal limited the amount of blast to about 8,000 cu. ft. of air per min.; in June, to about 8,900 cubic feet. For a few days in July about 10,000 cu. ft. were blown, and then the maximum daily output, 173 tons (2,240 lb.), was reached. At all times the quality of the charcoal was poor, having been made from wood cut from three to four years before. Doubtless this furnace could have produced 200 tons of iron per day, even with this quality of charcoal, provided the supply had been sufficient; and with

Jan 1, 1906