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By Erwin J. Durrer

The development of planning in the petroleum industry is de- scribed and the current status analyzed. Worldwide transportation networks led to corporate models which caused a differentiation between operations research and planning groups. Ranking of projects solely by ROI proved infeasible because of the diversified nature of the industry. Qualitative elements such as synergism with ongoing operations and the external socio-economic environment had to be included, leading to business plans based on scenarios of possible futures and stressing growth-opportunities over cash-flow rich mature product lines. In addition, decision analysis is finding applications in large capital, high uncertainty situations such as planning for synthetic fuel development.

Jan 1, 1977

By Forrest W. Kinsey

The use of pellets in North American blast furnaces has made the mixes used in the associated sinter plants unique. These mixes generally contain a high percentage of fine waste oxide materials as the principal iron bearing portion of the mix, with iron ores and concentrates added in minor amounts only. Additionally, the sinter basicity is always above one and can be three or higher. This paper will discuss the large body of knowledge and experience developed by one company on this type of sinter mix. Results of laboratory tests will be used to illustrate how mix composition and feed preparation affect sinter productivity and quality.

Jan 1, 1977

By C. Kasatuka

Globalization creates investment opportunities for enterprises around the world. Attracting foreign investment has been a key challenge for economic growth in developing countries. Corruption, political instability, armed conflict, and other internal problems affect foreign direct investment (FDI) inflows negatively. A framework of criteria provides a basis for comparing non-commercial risk (NCR) among twenty-three mineral economies. Countries competing for foreign direct investment inflows are ranked from least to most risky. This study compares Inward FDI Performance Index (IND) with NCR ratings in developing countries and shows that risk is increasingly mitigated by means of appropriately structured insurance. Given the option for countries with similar mineral potential, investors will generally invest in the country that offers lower non-commercial risk. Keywords: foreign direct investment, non-commercial risk, developing countries.

Jan 1, 2006

By D. Harrington

"In at least three out of every four working faces in metal mines there is no attempt made to cause air circulation other than by use of compressed air, and in at least nine cases out of ten the compressed air is released merely by opening, or partly opening, the valve and allowing the compressed air to escape through open air hose used to convey the compressed air to the drilling machines. Usually no blowers are in use during periods of drilling, as the exhaust from the drill provides cool, comparatively fresh air for the driller; however, in some instances, the compressed-air line is provided with a tea connection, which permits taking air for the drill from one side of the tee, and air for ventilation through a separate hose used as a blower, simultaneously with drilling.Table 1 contains temperature and humidity data as to compressed-air blowers from open end of air hose at 36 working places in eleven metal mines of four States, embracing the mining of gold, silver, copper, lead and zinc ores, and at horizons ranging from 500 feet below the surface to as low as 4900 feet.It is noticed that the ordinary air surrounding the worker at the face gives an average wet bulb temperature of 81.7° F. for the 36 working faces, with 84.7° F. dry bulb and 87.2 per cent relative humidity. The average wet bulb tem¬perature of 36 readings at these working faces of compressed air at the end of the,hose as the air issues from the hose was 67.4° F., or 14.3 degrees lower than the average wet bulb readings of the air of the working places; however, the average dry bulb temperature of the 36 readings of compressed air as it issued from the end of the hose was 79.7° F., or only 5 degrees less than that of the general air (84.7°); the relative humidity was 51.1 per cent as against 87.2 per cent for the surrounding air. Readings were taken in five raises, seven crosscuts, ten drifts and 14 stopes.It will be noted that the velocity or movement of the general atmosphere at each of the entire 36 working faces, was found to be practically imperceptible; this might readily be inferred since compressed air is rarely used on blowers if there is adequate circulation of the general air of the place. Where rook temperatures could be obtained readily, they are shown; it is noticeable that the dry bulb temperature of the air of the working place varies little from the rock temperature, and that the dry bulb temperature of the compressed air as it issues from end of air hose varies only a few degrees from the temperature of the surrounding rock; in some instances the dry bulb temperature of the compressed air as it issued from the end of the air hose was higher than the rock temperature or the dry bulb temperature of the surrounding air."

May 1, 1921

By Burgess JM

Research on gas distribution in the iron- making blast furnace has been conducted in three separate areas. Firstly, experimental work has been conducted to determine the important parameters which dictate the pressure losses in homogeneous and heterogen- eous packed beds. Secondly, a theoretical analysis of gas flow through the furnace softening-melting zone has been undertaken to determine the effect of the shape of the zone on the distribution of gas flow towards the furnace walls. Thirdly, a theoretical programme has been undertaken to develop methods for the prediction of furnace soften- ing-melting zone shape from furnace tempera- ture and gas composition measurements.

Jan 1, 1980

By Leon Keller, William R. Van Slyke, James Stukel

Two 4-ft wide DSM screens were installed during 1957 in one unit of the two-unit heavy media cy- clone section of the Holman-Cliffs concentrator at Taconite, Minn., following successful laboratory test work on a 1-ft screen. The two screens materially reduced the amount of media sent to the magnetic separator cleaning circuit. Wear life was good and fine size capacity was high. Briefly, the Holman-Cliffs heavy media cyclone plant uses -65 mesh magnetite as media and 10-in. diam., 30º Ni-Hard cyclones as separatory vessels. Feed to the plant averages 130 long tons per hr of -1/8 in. +65 mesh material. The conventional heavy media circuit uses drum or spiral type separatory units and treats +l/8 or 3/16-in. material. The medium is generally -65 mesh ferrosilicon. Ore and media are readily separated by screening at about 6 mesh. At this size, capacity is high and wear and maintenance are not excessive. The heavy media cyclone plant requires an efficient separation between +65 mesh ore and -65 mesh media. To reduce costs, however, the separation was made at a coarser size with the result that the media was un- duly contaminated and it was necessary to clean large tonnages of media and ore in magnetic separators. Due to the high capital cost of these units, their number was kept to a minimum and, consequently, they were overloaded. As a result, the separation between magnetic media and nonmagnetics was not sharp and the magnetite losses were high.

Jan 10, 1958

By Richard Newcomb

Since the report of the 1972 Rapid Excavation Conference in the city of Chicago, speculation has continued concerning the estimates of tunneling demand. Little has been published that would persuade me to modify substantially the rather tentative estimates that originated with the National Academy of Sciences-National Academy of Engineering (NAS-NAE) study of 1968 which were recomputed by the United States in the survey of the Organization for Economic Cooperation and Development (OECD) in 1970. The OECD estimates, of course, hedged the really difficult question of forecasting civil construction tunneling demands. In the United States contribution, this was done by predicting both an upper and lower bound for important categories of demand. A discounting procedure was then applied to each of the major sectors of expenditures, permitting a forecast that reflected the current subjective assessment of how extensively and how likely cities were to adopt plans that required tunneling. This was done for water, utilities, transportation and other novel underground facilities. The purpose of this paper is a modest one. In it I wish to describe the efforts made since 1972 to generate more thoughtful and more robust estimates of urban sector demands, and to apply what has been learned to the most difficult category of predictions: those for urban mass transit systems. The estimates of the Underground Construction Research Council funded by the National Science Foundation have been described at an earlier panel of this Conference. The principal effort I am familiar with is that of

Jan 1, 1974

By P. Chris Pistorius

Calcium treatment of alumina inclusions, to convert the alumina to molten or partially molten calcium aluminates, is a well-established treatment for steel, to improve the castability of aluminium-killed steel. However, the role of magnesium in calcium-treated steel is not fully clear, nor is the origin of the several percent of magnesium oxide that is often present in calcium-treated inclusions. To study this, steel was sampled after calcium treatment at an industrial steel plant, and the inclusions identified by energy-dispersive X-ray microanalysis (EDX) on polished sections of the samples (analysing the samples in a scanning electron microscope). The predicted fraction liquid in the inclusion was estimated from the ternary alumina-magnesia-lime phase diagram. Inclusions with higher CaO contents generally had lower MgO contents, indicating that the calcium wire is not the origin of the magnesium in the inclusions; this was also confirmed by wet chemical analysis of the calcium wire. Instead, it appears that magnesium-alumina spinel inclusions form during extended ladle contact after aluminium killing and before calcium treatment. While such spinels have been stated to cause poor castability (clogging the submerged-entry nozzle), it is clear that calcium treatment successfully modifies the spinel inclusions to mixed alumina-lime-magnesia inclusions, where the magnesia content contributes substantially to liquefaction of the inclusions: for typical MgO contents of around 10%, the range of Ca:O ratios which yield liquid (or partially liquid) inclusions is extended substantially to lower Ca:O ratios.

Jan 1, 2006

By John S. Bell, J. M. Shepherd

pressure difference of 280 psi measured initially on opposite sides of the major fault in the Hawkins Field led to pressure determinations in the Woodbine sand throughout the East Texas basin. Considering the large area, there is unusually good correlation between pressure losses and points of major withdrawals, these losses indicating that the basin pressure has been materially reduced by withdrawals, primarily from the East Texas Field and secondarily from the old fault-line fields of Limestone and Navarro counties, with the pressure loss varying inversely with the log of the distance from these two main areas of basin withdrawals to the measurement points. Apparently faults located throughout the basin serve as local blocks to continuous pressure gradients. INTRODUCTION The pressure anomalies found in the Hawkins Field, Wood County, Texas,' shortly after discovery have led to an area-wide investigation of the pressure distribution within the Woodbine sand of the East Texas basin. These pressures were obtained by drill-stem tests made for that sole purpose while drilling wildcat wells to deeper horizons. The Woodbine sand of Gulf Cretaceous Age is or has been productive of oil and gas in 42 different fields, with the 28 oil fields currently active having produced 118,000,000 bbl of oil during 1949. With one exception, producing energy for all Woodbine reservoirs has been from water drive provided predominantly by expansion of the tremendous volume of water contained in the Woodbine sand. This producing mechanism was recognized at an early date and was described mathematically by

Jan 1, 1951

By John S. Bell, J. M. Shepherd

pressure difference of 280 psi measured initially on opposite sides of the major fault in the Hawkins Field led to pressure determinations in the Woodbine sand throughout the East Texas basin. Considering the large area, there is unusually good correlation between pressure losses and points of major withdrawals, these losses indicating that the basin pressure has been materially reduced by withdrawals, primarily from the East Texas Field and secondarily from the old fault-line fields of Limestone and Navarro counties, with the pressure loss varying inversely with the log of the distance from these two main areas of basin withdrawals to the measurement points. Apparently faults located throughout the basin serve as local blocks to continuous pressure gradients. INTRODUCTION The pressure anomalies found in the Hawkins Field, Wood County, Texas,' shortly after discovery have led to an area-wide investigation of the pressure distribution within the Woodbine sand of the East Texas basin. These pressures were obtained by drill-stem tests made for that sole purpose while drilling wildcat wells to deeper horizons. The Woodbine sand of Gulf Cretaceous Age is or has been productive of oil and gas in 42 different fields, with the 28 oil fields currently active having produced 118,000,000 bbl of oil during 1949. With one exception, producing energy for all Woodbine reservoirs has been from water drive provided predominantly by expansion of the tremendous volume of water contained in the Woodbine sand. This producing mechanism was recognized at an early date and was described mathematically by

Jan 1, 1951

By Thomas P. Battle

Modern-day direct reduction of iron first developed as a small-scale, low capital and operating cost alternative to the blast furnace. Since commercialization of continuous DR technology in the late 1960s, the market for the products of direct reduction has grown to more than 74 million tonnes in 2012. The initial advantages of DR plants over BF facilities have grown over the years, for several reasons, including the increased size of DR modules, lower energy and emissions (particularly CO2), along with the flexibility to use a number of different reductants. The development of DR technology over the past forty years will be emphasized in this presentation, including recent developments that allow for even more direct sustainability comparisons with the iron blast furnace – and even combine the two technologies for improved synergies. Also briefly discussed will be the possibilities of using direct reduction for non-ferrous ores.

Jan 1, 2014

Human creativity springs from the natural desire of mankind to know and its capability to learn. Explorers and discoverers possess these features in a high degree. They are driven by an unrelenting curiosity to go beyond the boundaries of the known, to explore into the nature of things, to reveal connections between ideas, facts, conceptions, to view things from new angles, to change perceptions. A well-known fact about the construction industry - and underground construction in particular - is that all projects are unique. The degree of complexity due to the intertwining of the variety of project-related parameters is higher than in many other industries, thus forcing contractors as well as suppliers to be truly adaptable and flexible. The enormous advantages of shotcrete as a construction and rock support process and the improvement of materials, equipment and application know-how have made it a very important and necessary tool for modern underground construction works. The development of modem wet shotcreting in particular has enlarged the field of underground construction work. Projects that were impossible to be realised, have now become practicable. Subsurface structures can be placed where they are needed, without regards as to rock and soil conditions.

Jan 1, 1995

By Mao Chen, Baojun Zhao, Zhixiang Cui, Leonel Contreras, Chuanbing Wei

Bottom blown oxygen copper smelting process developed at Dongying Fangyuan Nonferrous Metals shows many advantages such as flexible feed requirement, high productivity, low energy consumption and high direct copper recovery. However, the weak acid generated during the process is not stable which influences the waste management and continuous operation. The amount of the weak acid is determined by SO3 formed in copper smelting process. SO3 can be formed inside copper smelting furnace and boiler at different conditions. Effects of temperature and oxygen partial pressure on the formation of SO3 during copper smelting process have been discussed thermodynamically. Understanding of the mechanisms for SO3 formation will enable the operation of bottom blown copper smelting furnace to be optimized and generation of the weak acid in the process can be managed. The fundamentals developed in this study can also be applied to other copper smelting processes.

Jan 1, 2016

By S. N. Monteiro, E. B. Zanelato, J. Alexandre, M. T. Marvila, A. R. G. Azevedo, G. C. Xavier

One of the parameters used in the study of mortars is the adhesion resistance, which indicate show much the mortar adhered to the substrate. The usual study is done at 28 days, to worldwide standardization. Few researchers study the adhesion of mortars to ages other than 28 days. In this scenario, the adhesion strength tests of conventional mortar with a 1:1:6 mass scale (cement, and sand) at 7, 14, 28, 56, 91, 182 and 364 days were performed in order to understand the behavior of this material. The usual characterization tests of the mortars were carried out to correlate the values obtained with the adhesion results. The obtained results demonstrate that the mortar continues to gain resistance with the passage of time. For the trait studied the gain was considerable, indicating that over time the cement continues to hydrate, reacting and contributing to the strength of the material.

Mar 1, 2018

By I. R. Firth, D. L. Taylor

Metal mining operations, in particular gold mining operations, use intensive ore control procedures in order to manage the extraction of ore zones from benches containing both ore and waste material. Typical grade control procedures rely on blast hole samples to indicate ore grade. Statistical techniques and geological controls are then used to create two-dimensional polygons, which indicate zones of material designated as ore. These ore-polygons are calculated using pre-blast material locations and are generally not corrected for rock movement caused by blasting. This lack of correction appears to exacerbate the material mischaracterization problem of sending ore to the waste dump and/or waste to the mill. One Nevada gold mining company has estimated that this could be a $10 million per year problem for their operations. Using a simplified vector field algorithm, a method of taking point movement data and interpolating post-blast positions for all nodes in a polygon has been developed. Currently working in 2-dimentions (X-Y), this algorithm utilizes the movement vectors calculated from pre-and post-blast positions of targets placed in a blast, to generate a spatial transformation function for any point on the bench. This transformation is then applied to the nodes of the ore-polygons to produce modified dig lines ore polygons reflecting distortion and movement resulting from the blast. The method as implemented uses common mine planning routines and is performed using the Surpac software suite. The method may be adapted to use any pre-and post-blast point movement data available, and most mine planning suites include the simple interpolation algorithms used. Keywords: Blast movement; Ore control; Open pit blasting; Grade control

Jan 1, 2003

By W. J. Mcgaughey

A crosshole seismic imaging (tomography) experiment has been carried out in an underground mine in order to delineate waste rock within a massive sulphide ore body. Data comprising 1526 travel time measurements were inverted to yield a compressional wave speed image consistent with, and adding to, knowledge of the extent of the waste inclusions. An effective method of resolving travel time discrepancies measured on reversed ray paths is presented.

Jan 1, 1989

By Yoshikazu Hirosaki

How big or small is the Japanese explosive market? Who are the major explosive customers? Is there any big construction project in which a large amount of explosives is expected? What is the future of the explosives industry in Japan? Is it true that there are no ANFO trucks? What is the licensing system for blasters? Is there any education system for blasters?

Jan 1, 2001

By H. A. D. Kirsten

The skills differential between manpower supply and demand is due to deeply rooted socio- and politico-educational misconceptions that can be remedied only by a concerted cooperative effort on the part of the general public, the State, organized industry, organized engineering, and engineering education. This will require the general public to recognize that the reasons for the shortages in engineering manpower should be regarded as critical. Public perceptions of engineering, of the vocational and educational prospects in engineering, and of the skills required are poor. The spectrum of engineering vocations, the corresponding function profiles, the interaction between the vocations and the relative proportions of the vocations in the engineering team are in general not adequately appreciated. The recruitment and training of students and teaching staff, teaching facilities, educational curricula, practical training, qualifications, professional registration, and financing are aspects of engineering education that should be brought to the attention of all concerned. . In addition, the educational curricula for the various vocations need to be specified clearly and definitively if the overall mission of engineering education is to be properly appreciated. The uncertainties between university and technikon education and the pursuant vocations need to be resolved. This can be done only by defining the respective curricula in terms of the mental skills and scientific techniques required. The remedial actions with regard to the rationalization of engineering education comprise informing of the public; establishment of an active political lobby; revision of existing education policy; rationalization of existing educational infrastructure; promotion, development, and guidance of engineering student intake; financing of engineering education; accelerated creation of new employment opportunities; and monitoring of the supply and demand of high-level manpower. The parties required to nitiate these remedial actions are various State departments and corporations involved in engineering and industry, various departments of education, the Directorate of Technology of the Department of Trade and Industry, organized engineering education, organized engineering, organized industry, and the Human Sciences Research Council. Only if these interest groups actively initiate the various actions under the coordinated guidance of organized engineering wil the required results be achieved. The South African Engineering Association has proposed a comprehensive programme as strategy to solving the problem, and has obtained broad consensus from various State departments, organized engineering education and research, and the private sector. A joint venture between the Foundation for Research Development, the South African Engineering Association, and organized industry has been charged by the State President with the task of launching the programme.

Jan 1, 1991

By Byron W. Cheever

In my paper on the estimation of manganese, etc., presented at the Halifax meeting, in September, 1885 (Transactions, xiv., 372), I said that the colorimetric process "can never be made to give reliable results." This statement was based on the results of many trials made by my assistant, Mr. E. D. Campbell, and myself, following in our work the printed and oral directions of others, and such modifications as suggested themselves from time to time. The accuracy of the statement having been questioned, I have, since then, endeavored to find some method of conducting the operation which would give accurate results; I have also tried the methods used by five different chemists; and I am not able to bring the process within the limits of an exact method. While it can fairly be ranked with the colorimetric carbon-process, and can be used for checking the operations of a steel plant, yet it requires more care to obtain uniform results, and is liable to greater variations from slight causes than the carbon-process, and, in my judgment, is not a safe method to employ when exact results are sought.

Jan 1, 1887

By Michael G. Nelson

In 1992, the Alaska Department of Environmental Conservation received a grant from the Environmental Protection Agency (EPA) to fund the reclamation of an abandoned placer mine. The project also included the development of a water-quality and hydrologic-monitoring program. The grant was provided under Section 319 of the Clean Water Act and is administered through EPA's Region X Water Division. For the past 100 years, Alaska's interior has been the site of extensive placer-mining operations. Early surface and underground operations left small tailings piles, some of which are still visible. Dredging left larger tailings piles, similar to those in California and elsewhere. The only reclamation of these tailings involved use as road base and fill and other civil applications. Most active mines in Alaska are on state and federal lands. The standards of reclamation for mines on federal lands are established under US Mining Laws, 43 CFR 3809. They address only mines operated since 1981. Under a state statute passed in 1990, the Alaska Department of Natural Resources, Division of Water and Mining, has issued reclamation regulations. These regulations apply to sites on state, federal and private lands, but only those mined since Oct. 15, 1991.

Jan 1, 1995