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By M. Pesowski

"Certain environmental problems can substantially alter the physical properties of the subsurface. In such cases, geophysical methods can be used to map the distribution of subsurface contamination or buried wastes prior to drilling or sampling. For example, inorganic contamination by acids, bases, salts, or metallic ions can be detected by instruments that measure ground conductivity; metallic objects such as buried drums, pipelines, etc. can be located by magnetic survey, and radioactive mine waste can be mapped by radiometric techniques. Geophysical methods can also be used to characterize site geology. If carried out prior to development, they can assist in identifying areas of high- and low permeability and sources of natural contamination. The methods can also be used to establish baseline values and to locate stable areas for development of environmentally sensitive facilities. Application of geophysical methods to environmental problems is illustrated with examples from base-metal mines, uranium operations, and potash and oil-sands operations. Particular attention is given to the problem of acid mine drainage. =IntroductionGeophysical methods have been used for many years by the mining industry in exploration and geotechnical investigations. The basic techniques for mapping variations in physical properties of the subsurface have been adapted to meet the special needs of resource exploration and development in the coal, potash , oil sands, industrial minerals, precious metals, and base-metal industries. Now the mining industry is facing another challenge: to operate the mining cycle, from discovery to closure, with minimum impact on the environment. This involves the rehabilitation of abandoned mining sites, the minimization and effective containment of pollutants at operating and developing sites, and the longterm containment and monitoring of sites after mine closures.Some of the most difficult aspects of environmental control and monitoring relate to the location of buried waste and contaminated fluids in the subsurface. As in the search for buried ore deposits or in geotechnical investigations, geophysics can be a valuable aid in subsur face environmental investigations. Investigations can be remedial , involving the location or monitoring of existing problems, or preventative, where problem areas are identified or background values are established before site development. In either case, geophysical methods should not be considered as a substitute for drilling. Geophysical interpretations in general do not provide the detail required for a complete environmental or geotechnical investigation. They are most useful as rapid reconnaissance methods for targeting subsequent drilling or for interpreting subsurface condit ions away from drill holes. Table I lists the common geophysical methods and the physical properties to which they are sensitive."

Jan 1, 1993

By Charteris A. Stewart

The following scanty notes on the Roumanian oil-region may serve as an introduction to more detailed future study and description. The Roumanian oil-belt follows the outer edge of the sweep of the Carpathian mountains, and may, in a broad sense, be regarded as a prolongation of the Galician belt. It is distributed over a tract of country from 300 to 400 miles in length, with a width of from 15 to 20 miles, and is believed to cover an area of at least 20,000 hectares (49,420 acres). The governmerit claims that 16,000 to 17,000 hectares of its land is petroliferous. The primary deposits of petroleum arc considered to be in the Paleogene (Oligocene) and the Neogene (the salines of the Miocene) formations. Most of the other repositories, especially those of Muntenie, are only secondary, the petroleum there having been introduced by the orogenic movements which raised the Carpathian mountains. The oil-field has been divided by the Roumanian Survey into two regions, the Flysch and the Sub-carpathian, as is shown in the accompanying sketch-map, Fig. 1. So far as is yet known, practically all the seepages and productive pits and wells are situated on anticlinals. Those which outcrop in the Flysch region (called Paleogene anticlinals), as indicated in the sketch-map, Fig. 1,are : Solontz,

Jan 1, 1907

By Lester Uren

WITH the depletion of our older, and relatively shallow, oilfields and the necessity for securing new production from deeper horizons, much attention is being given to the improvement of oil-well pumps in order that they may function satisfactorily under the more difficult conditions imposed by increased depth. Until recently, practically all of the world's petroleum was secured from wells less than 3000 ft. deep, whereas horizons are now being explored to depths of from 5000 to 7000 ft. in some of the more prolific fields, and it seems probable that the greater part of the future supply must come from depths in excess of 3000 ft. While much of the early production in a new field is obtained by natural-flow methods, when the stimulus of high gas pressure fails, recourse must be had to some method of pumping. The perfection of a pump capable of economically and efficiently lifting oil from depths ranging from 3000 to 7000 ft. is therefore a matter of prime importance to the oil-producing industry. This paper is offered as an estimate of the present state of development of the oil-well plunger pump and as a review of the general principles involved in its operation in deep-well pumping. A design for a new type of oil-well pump embodying several novel features, is also described.

Jan 9, 1925

By J. B. Cheatham, M. D. Biggs

This paper presents a systematic method for determining the forces on a simplified roller bit. The kinematics of an actual roller bit drilling in rock is complex; nevertheless, it is desirable to obtain an accurate analytical model.. As a preliminary study, the roller bit is represented here by a simple two-dimensional bit and the rock by a Coulomb plastic material. Results from previous work, plus additional assumptions, are incorporated into a computer program to determine the forces required to move the bit in a specified manner. Example problems are worked by use of this program. By studying similar drilling problems and by supporting laboratory work, one could eventually obtain an accurate analytical model for drilling by an actual roller bit. This could lead to the compilation of a catalog of results that, in turn, would allow selection of the optimum drill bit for any given situation. INTRODUCTION

Jan 1, 1970

By T. S. Golosinski

This article reviews current contract mining practices in Australia. Various types of contracts are reviewed, including partnering arrangements and alliances between the contractor and the mine owner. Applicability is also discussed of various types of contracts to specific mining situations, as is their effect on overall mine performance.

Jan 1, 1998

By S. K. Das Gupta

The rock laterite was first discovered and described in the State of Kerala, India in 1800 A.D. by Francis Buchanan. It had been used here, and elsewhere in India, for many centuries as a building stone, but in Buchanan's time it was not known that some of these laterites were highly aluminous and could be processed to produce alumina. After World War I India started searching for bauxite reserves with a minimum grade of at least 50% A12O3. By 1960, it was estimated that India had a potential reserve of 245 million tonnes of bauxite, about 10% of which was in the "Proved" category. Subsequent geological exploration now reveals that India has an overall resource of more than 2 billion tonnes of aluminium ore, not all of it bauxite, as defined by earlier geologists. In this paper, the geology, resources and distribution of bauxite and aluminium ore throughout India are described. The generalised stratigraphy, typical laterite and bauxite profiles and summary of the resource position are shown in the attached Tables 1 to 8. It is generally agreed that a tropical to sub-tropical climate, intermittent wet and dry season, good permeability of country rock and suitable drainage, as well as physiographic and ground water conditions are important in the development of bauxite.

Jan 1, 1984

By K. Hakalehto

El uso de métodos modernos en el uso de chimeneas de las minas en Finlandia permite obtener un mejor desarrollo racionalizado de la mecanizado. En ese sentido, el presente texto señala dos métodos seguros y rápidos para la perforación de chimeneas. La perforación para estas chimeneas se desarrolló en rocas duras duras y fuertes en 1972. Asimismo, el costo, itinerario y velocidad son factores a considerar en el empleo de métodos para perforación de chimeneas.

Jan 1, 1982

By J Player, G Sweby

The material properties and hence performance of saturated alluvial sediments slope can be incorrectly forecast if the water content is not preserved, and materials properties not correctly determined. The occurrence of saturated sediments in the Western Australia (WA) Goldfields, while not common, should be a significant investigation focus. Geotechnical engineers new to the area may be unaware of this and hence the importance of correct testing and determination of the material strength. Application of appropriate analysis to determine stable pit slopes to an acceptable level of risk, is not possible unless the appropriate strength and hydrogeological parameters have been established at the outset. A back analysis is presented of a pit that had extensive slope failures in alluvial clay-rich sediments with discussion on the approach adopted by the original design engineers to assess pit wall stability and consequent poor slope performance. Learnings from a full pit 3D back analysis are presented, with an approach to geotechnical and hydrogeological investigations and analysis for slopes in similar materials.

Jun 22, 2022

By H. A. Doerner

"The pure mineral chromite, FeO.Cr203, consists of ferrous and chromic oxides, chemically united in equal molecular proportions. Unfortunately, pure chromite as defined above appears to be a rare exception. In most chrome ores the mineral may be considered a combination of spinel, MgO.Al203, and chromite, with the latter predominating. The ratios between the four common constituents Fe0, Mg0, Cr203 and A203 vary greatly, and other minor constituents such as TiO2 and. Fe203 may also be present.In the mechanical concentration of chromite ores the maximum grade of concentrates that can be produced is thus limited by the composition of the chrome minerals present. Pure chromite contains 68 per cent Cr203, but the Cr203 content of the chrome minerals in commercial ores varies between 45 and 60 per cent and the average is not far from 55 per cent.Chromite is usually associated with serpentine. Other silicates, quartz, dolomite, magnetite, ilmenite and other iron Minerals are frequently present.The amenability of a chrome ore to concentration, depends upon the kind and amount of the various gangue minerals present and the amount .of crushing necessary to separate the chromite from them.A relatively small amount of chrome ore is concentrated by milling. In most cases the mine product is simply hand-sorted. Such chrome deposits as are known in the United. States can not be worked in this way on account of one or both of the following conditions: High cost of labor and finely disseminated impurities. There are, however, several deposits in the United States, Canada, and Alaska which may be able to compete with imported or by efficiently utilizing modern ore-dressing and milling methods."

Nov 1, 1930

By H. R. Babitzke

The purpose of this investigation was to develop an alloy of columbium for use at high temperatures and for nuclear applications. The properties of possible alloys were determined, and the more promising ones were selected for further improvement. Criteria for selection were machinability, hardness, workability, tensile strength, and oxidation resistance. Thirteen 100-gram ingots, ranging from 100 percent columbium to 100 percent vanadium, were prepared and subjected to various tests. Also included for comparison were zirconium and the zirconium alloy, zircaloy-2. Test results showed that a columbium alloy, containing 10 atomic percent vanadium merits further development. Besides being workable at room temperature, the columbium-10 atomic percent vanadium alloy has oxidation resistance superior to the other alloys of the series and is also superior to zirconium or zircaloy-2. The latter two materials have comparable neutron-absorption cross sections. The strength and hardness values of the alloys tested were found to increase with increasing vanadium content, reaching a maximum at 50 atomic percent vanadium and decreasing with further increase in vanadium. This behavior is typical of binary alloys wherein each element will retain any proportion of the other in solid solution. INTRODUCTION There is an increasing need for alloys for service at high temperatures. Since current world reserves of columbium metal approximate 1,500,000 tons (1),4 this metal is now readily available. Columbium can ties; be considered a practical base material for high-temperature alloys required in nuclear reactors and in aircraft and space vehicles. General requirements chosen are: (1) Workability, (2) satisfactory mechanical properties at temperatures approaching 1,000° C., and (3) resistance to oxidation at such temperatures.

Jan 1, 1962

V. H. GOTTSCHALK, Rolla, Mo. (written discussion*).-In connection with Mr. Waring's quotation of Urbain's work, attention may be drawn to a remark found in the report of the session of the Société de Chimie Physique,1 held in December, 1909, that, while all blendes contain gallium in larger or smaller quantities, those blendes carrying indium are generally free from germanium, and vice versa. Urbain, furthermore, . expresses his conviction that this behavior, being related to the condi-tions of deposition of the ore, should be an important factor in determining the origin and mode of formation of zinc blende deposits., In. searching the literature for the naturally expected sequel to these remarks, there is found a report on the extraction of germanium from blende, after many months' work, on a commercial scale;2 then a paper3 on some Spanish blendes, all containing cadmium, examined by Urbain's 'method (this paper contains, also, very important work on the com-position and color of blendes, as well as on the occurrence of organic .matter and of inclusions in such blendes), and a second paper on Spanish blendes in general, in which this original point of Urbain's concerning the relative quantities of the three rare elements is taken up.4 Angel del Campo finds that of 68 specimens examined, four only were entirely free of germanium, gallium, and indium;. 38 had small proportions, while 19 were notably, and seven relatively rich in the three rare metals. He found the relative frequency to be: gallium in 60, germanium in, 50, and indium in 38; all three occurred in 29 cases; germanium and gallium together in 18; gallium and indium together in four; germanium and indium together without gallium, in none; four had gallium only, three had germanium only, and one had indium only; in 23 it appeared feasible to extract these elements. Finally, it may be worth mentioning that the discovery of gallium in commercial aluminum5 brought forth two

Jan 1, 1918

"Shales play a major role in the stability of slopes, both natural and engineered. This paper attempts to provide a review of the state-of-the-art in shale slope stability. The complexities of shale terminology and classification are first reviewed followed by a brief discussion of the important physical and mechanical properties of relevance to shale slope stability. The varied mechanisms of shale slope stability are outlined and their importance highlighted by reference to international shale slope failures. Stability analysis and modelling of anisotropic rock slope masses are briefly discussed and the potential role of brittle rock fracture and damage highlighted. A short review of shale slopes in open pits is presented.INTRODUCTIONShales have been stated to form approximately 58% of sedimentary rock so it is not surprising that they are frequently encountered in both natural and engineered slopes. They represent challenging environments for slope stability due to the wide variation in their engineering properties, their changing behaviour with time due to geomorphic processes and the variation in the failure mechanisms as a function of both stratigraphy and tectonics. An extensive body of literature exists on the terminology and classification relevant to shales; it is not possible in the scope and length of the current paper to review these works in detail and the reader is referred to Farrokhrouz and Asef (2013), Bell (2000) and Goodman (1993) for detailed discussions. It is arguably the case that no universally accepted classification of shales exists today and depending on the field of application the terminology varies widely. Shales in slope stability, for the purpose of this keynote paper, are taken to include material varying in properties from weak rocks to soils and therein lies one of the most challenging aspects in shale slope characterisation for engineering purposes. They have been classified as “rock-like” or “soil-like’, (Underwood 1967) or compacted and cemented, Table 1, Yagiz (2001). Classifications have considered numerous factors including composition, cementation and a wide range of engineering properties.The propensity of shales to degrade with time due to geomorphic processes has resulted in an important aspect in their classification, that is, the attempts to incorporate slaking, durability and swelling and softening behavior through purpose developed testing methods (Gamble 1971, Morgenstern and Eigenbrod, 1974). Figures 1 and 2 show examples of terminology used to describe argillaceous materials and some proposed engineering classification schemes (Grainger 1984 and Bott 1986). Corominas (2014) provides a recent classification of argillaceous rocks and their durability relating five stages of slope deterioration to the texture of the rock on Ternary diagrams. No attempt will be made here to discuss the merits of the proposed terminology and classifications, suffice it to say, that the controversy and flux surrounding these issues is a strong indicator of the complexities in the behavior of these materials. In this paper the author will consider slope stability in the materials indicated in Table 1, Figures 1 and 2 without undue focus on terminology. At the lower strength limit of shales the engineer must design slopes using the principles of soil mechanics which may vary from the simple Mohr Coulomb plasticity constitutive criterion to modified critical state models, some even attempting to incorporate softening behaviour in the weaker clay shale materials. Given the transitional nature of shale materials several workers have treated overconsolidated clays and clay shales using concepts such as peak and residual shear strength, brittleness index and softening. Martin and Stacey (2013) provide a useful review of the importance of weak rocks in open pit mining, with mudrocks as a specific member, and note the importance of delayed failure, progressive failure and loosening in the stability of"

Jan 1, 2015

By D. J. Freeh, W. E. Horst, R. C. Kellner

This paper is concerned with the description of grinding characteristics in a batch grinding system. A mathematical model was developed and used for simulating the system on an analog computer. A general equation describing the change of selected size fractions with respect to time is presented. The empirical verification of the model is discussed. In order to understand the performance of a grinding system, it would be desirable to have a mathematical description of the system's behavior. The development of a mathematical model to describe the performance of a batch dry-grinding operation was investigated. This is the first step toward reaching the objective of a practical mathematical description of a grinding system that could be employed for process control and optimization of a simple or complex grinding circuit. Although this article is concerned only with batch grinding performance, experimental work is being conducted to extend the model to continuous grinding systems. BASIC PROCESS CONSIDERATIONS In a paper dealing with the probability theory of wet ball milling, Roberts1 correlated the rate of change of oversize material, C, with energy input, E, as follows where the energy input is expressed in power/unit mass and k is a constant for each particle size. Experimental grinding studies were made by Bowdish2 to extend the previous work of Roberts. The work of Bowdish also showed that the rate of breaking of oversize particles in a ball mill is proportional to the concentration of oversize particles present. He further demonstrated that breaking of oversize particles is proportional to the surface area of the balls used for grinding. Rate equations were presented and it was concluded that grinding could be considered as a first order phenomenon according to the rate equation [2] di which is in accordance with Eq. 1. In Eq. 2, the effect of ball area is included in the constant k,. Other rate equations were reported to show the effect of a change in ball area and removal of fines during grinding. Correlation studies made by Arbiter and BhranY indicate a first-order rate equation for quartz; however, their data showed less than first-order rates existed for some of the other materials evaluated. More recently Kelsall4 has shown that the rate of breakage of any narrow size range of quartz could be described by a first-order rate equation. Several other investigators5-7 have described grinding behavior in terms of rate equations or kinetics. In general, the rate equations have been described for each particle size; however, the interactions between sizes and the overall relationships that exist have not been considered, at least not in the form of solving a group of simultaneous differential equations. Extensive work has been conducted by various investigators using a probabilistic approach which has expanded stein's' earlier work. Selection and breakage matrices are incorporated in the probabilistic model as contrasted with the deterministic method presented here. A batch grinding operation may be considered as an unsteady-state process from the standpoint that the conditions within the mill are a function of time. Therefore, a plot of mass fraction of the i-th size versus time would give a set of curves as shown in Fig. 1. In these curves X , represents the mass fraction of large size material, X2 intermediate size, and X3 small size material. An examination of these curves shows a strong similarity to the curves that would be obtained from a chemical reaction of the type9 A?B?C, [3] where A would be comparable to the largest size material being broken to an intermediate size, 3, and

Jan 1, 1968

By Z. Rogovin

In order to develop more accurate procedures for scale-up and design of semi-autogenous-grinding mills through detailed mathematical models, a better understanding of the charge motion and rock/ball segregation is needed. To achieve this a 0.61 m (2.0 ft) diameter x 0.305 m (1.0 ft) length plexiglas mill was constructed as a scale model of a commercial SAG mill. Rock motion in the rotating mill was simulated using various sizes of ceramic balls. Quantitative measurements of dynamic angle of repose, water and slurry motion, holdup and size segregation of the charge were taken. In addition, a video-presentaiton (available to the public) was prepared to elucidate charge and water motion at various mill speeds, charge volumes, rock size distribution and flow rates.

Jan 1, 1985

By H. K. Livingston

A technique has been developed which makes it possible to determine the spreading pressure of liquids and solids, for simple systems. Data for surface tensions, interfacial tensions, spreading pressures, and contact angles for water, heptane, and silica are tabulated.' These results can be applied to the evaluation of capillary rise and displacement pressure in a petroleum reservoir. Appropriate equations are presented and the application of these equations is discussed. The presence of surface-active components affects both capillary rise and displacement pressure and also seems to influence the rate of fluid flow. The purpose of this paper is to supplement and bring up to date the last article on the subject of the surface chemistry of petroleum reservoirs, that of Garrison in the 1935 Oil and Gas Journa1.1 A discussion of the "adhesion tension" concept used by Garrison has been presented in another publication,2 together with the reasons for the recommendation that the term "adhesion tension" be abandoned. In view of the fact that some of the data used by Garrison have been superseded by more recent work, it seemed advisable to call attention to this fact and present the more important data currently believed to be correct. In the earlier paper, Garrison set up the equations that 'relate solid-oil and solid-water interfacial tensions to each other, and applied data from Bartell and Miller3 to these equations. However the adhesion tension measurements made by Bartell and Miller involved a confusion of symbols, so that they did not actually measure the spreading pressure, ?s — ?sf.2 The spreading pressure is a convenient method of indicating the amount by which the surface energy of a solid surface is lowered on immersion in a liquid or vapor. Since the initial value of the free surface energy is represented by the symbol ?s and the final value is ?sF, the spreading pressure is ?s — ?SF. A technique has now been developed4 that makes possible the determination of ?s — ?sF for simple systems. This method would be very difficult to carry out with a multicomponent system such as exists in the petroleum reservoir. However, already results have been obtained for ?s — ?sF for water and heptane in contact with silica and graphite. These values will be of the same order of magnitude as those in the petroleum reservoir. Accordingly, it is possible for the first time to discuss the surface-energy relations of the petroleum reservoir on a semi-quantitative basis. Preliminary Generalizations A petroleum reservoir may contain the following four phases: gas, hydrocarbon liquid, aqueous liquid, and solid. The three fluid phases are dispersed through the solid reservoir rock. If gravity were the only force acting, it is obvious that the

Jan 1, 1943

By H. K. Livingston

A technique has been developed which makes it possible to determine the spreading pressure of liquids and solids, for simple systems. Data for surface tensions, interfacial tensions, spreading pressures, and contact angles for water, heptane, and silica are tabulated.' These results can be applied to the evaluation of capillary rise and displacement pressure in a petroleum reservoir. Appropriate equations are presented and the application of these equations is discussed. The presence of surface-active components affects both capillary rise and displacement pressure and also seems to influence the rate of fluid flow. The purpose of this paper is to supplement and bring up to date the last article on the subject of the surface chemistry of petroleum reservoirs, that of Garrison in the 1935 Oil and Gas Journa1.1 A discussion of the "adhesion tension" concept used by Garrison has been presented in another publication,2 together with the reasons for the recommendation that the term "adhesion tension" be abandoned. In view of the fact that some of the data used by Garrison have been superseded by more recent work, it seemed advisable to call attention to this fact and present the more important data currently believed to be correct. In the earlier paper, Garrison set up the equations that 'relate solid-oil and solid-water interfacial tensions to each other, and applied data from Bartell and Miller3 to these equations. However the adhesion tension measurements made by Bartell and Miller involved a confusion of symbols, so that they did not actually measure the spreading pressure, ?s — ?sf.2 The spreading pressure is a convenient method of indicating the amount by which the surface energy of a solid surface is lowered on immersion in a liquid or vapor. Since the initial value of the free surface energy is represented by the symbol ?s and the final value is ?sF, the spreading pressure is ?s — ?SF. A technique has now been developed4 that makes possible the determination of ?s — ?sF for simple systems. This method would be very difficult to carry out with a multicomponent system such as exists in the petroleum reservoir. However, already results have been obtained for ?s — ?sF for water and heptane in contact with silica and graphite. These values will be of the same order of magnitude as those in the petroleum reservoir. Accordingly, it is possible for the first time to discuss the surface-energy relations of the petroleum reservoir on a semi-quantitative basis. Preliminary Generalizations A petroleum reservoir may contain the following four phases: gas, hydrocarbon liquid, aqueous liquid, and solid. The three fluid phases are dispersed through the solid reservoir rock. If gravity were the only force acting, it is obvious that the

Jan 1, 1943

By S. Chander

A mineral or metallurgical process uses various inputs, such as ores, energy and other raw materials, to make different products that fulfill societal needs. The processing of raw materials has changed in recent years due to the increased complexity of processing low-grade ores, intensifying competitiveness and greater constraints. For process improvement, various plant optimization and process modifications must be conducted under environmental, social, political and economic constraints. Processing research and education's success in meeting the process industry's future needs depends on an adequate balance between micro- and macro-engineering approaches. In its simplest form, macro-engineering is concerned with the "big picture," while micro-engineering requires looking at a subset of the process. So macro-engineering may be defined as an investigation of the larger or "whole" system to achieve the desired goals. And micro-engineering may be viewed as a quantitative investigation of a subset of the process, to determine cause-and-effect relationships within the subset. Two different approaches might be used in macro-engineering analysis. In one, the big picture may be viewed without a detailed knowledge of the subunits. With this approach, statistical tools are used to relate input and output parameters. Also, actual plant data or analog models might be used to obtain the desired information. The usefulness of such an approach increases with problem complexity. To attain the desired goals using the second, "model-based," approach, a detailed knowledge of the subunits is often useful and their interactions may be considered. In complex process analysis, the first of these approaches is more useful since less information is needed. However, it is also less exact and more likely to fail if there are significant changes in conditions and interactions. The second approach, on the other hand, is more exact, with greater predictive ability within the narrow subset being considered. Consequently, it is difficult and costly to conduct.

Jan 1, 1992

By Joe Milbourne

The potential for treating copper-nickel-cobalt-platinum group metal concentrates by a fully hydrometallurgical route is discussed. Processes specifically developed for treating these feeds and the potential application of the processes developed for the treatment of chalcopyrite copper concentrates are included in the evaluation. Block flowsheets are provided and the technical characteristics of various processes are compared. The current state of development for each process is summarized and probable economic impacts of the technical features are qualitatively assessed. Perceived risks and rewards associated with each technical concept are provided in the conclusions.

Jan 1, 2003

By J. H. Berryman

THE use of oxygen as a bath reagent in hearth furnaces during the refining period is a familiar story. Investigations and tests in which oxygen was substituted for iron ore to reduce carbon date back 25 years and include the work of Bigge,1 Browne,2 and Chelius.3 During this past year the majority of the experimental work in the use of oxygen was carried on mainly in open-hearth shops, since it was felt that the greater field for application lay in this type of furnace. Much constructive work was done in evaluating the carbon-oxygen relationships, as reported by Slottman and Lounsberry4 and by Hughes.5 Steelmakers using the electric furnace have been actively engaged meanwhile in an experimental program of their own, with such success that the oxygen injection pipe has become a tool in the day to day production of low-carbon and stainless steels.

Jan 1, 1947

By Gerard de Vries

pipeline industry and are still growing in size. Liquid epoxy and polyurethanes are an excellent choice for whatever the aggressiveness of the substance transported and whatever the harmful outside influences, maximum protection is required. They can be used as coatings on all kind of pipelines varying from the mainline coating to the field joint coating. Compared with traditional systems like dual layer FBE and 3-layer polyolefin there are some benefits to be considered like easiness of repairs, amount of coats, application temperature and film thickness. The interior coating renders the pipe surface so much smoother that considerable savings can be realized in pump stations. Apart from the interior of the pipeline, the industry is faced with new challenges like higher operating temperatures of lines and an emphasis on product benefits in order to save money. Key words: liquid epoxy, liquid polyurethane, phenolic epoxy, pipeline, field joint coating, internal coating, corrosion control

Jan 1, 2006