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By H. H. Hill

"The wide publicity that is given to the discover; of new oil fields has led many people to believe that our supply of crude petroleum is practically in- exhaustible and that in order to keep pace with the demand for petroleum products, it is only necessary to drill a few more wells in some of the south-western states. It is not generally realized that, although many famous fields have been developed in Oklahoma, Kansas, Texas and Louisiana during the past few years, the production of crude oil in 1919 was not sufficient to meet the demand and it was necessary to import approximately 53,000,000 barrels from Mexico.Continued efforts are being made to recover a larger percentage of the oil underground by improvements in methods of drilling and in handling producing properties. Improvements are also being made in methods for handling the oil after it has reached the surface which will result in reducing losses through leakage and through evaporation. These methods for cutting down waste in production and storage, if universally adopted, will no doubt result in appreciable increases in our supply of crude oil."

Nov 1, 1920

This paper presents the results of research aimed at proposing new solutions in the area of belt conveyor elements. Many factors, such as energy consumption costs, and operating costs of belt conveyor elements, including belts, idlers and drives have an impact on the operational costs of conveyors. The paper presents special tests of new materials for the bottom cover of an energy-saving belt conveyor, which decrease rolling resistance. It also presents large-scale in-situ tests of a high-output belt conveyor for the purpose of simultaneous measurements of various types of conveyor belts (standard vs several energysaving types) under typical operating conditions of a lignite surface mine. Improvements in materials used for the bottom belt covers, supported by specially developed comprehensive tests of the new types of belts have provided valuable results of various proposed solutions. Since the tests of belts were done at exactly the same time and in the same operating conditions, direct comparison of the results is valid and should lead to a substantial decrease in the conveyors? drives? energy consumption, which will improve the effectiveness of belt transport and minimize its negative influence on the environment.

Aug 1, 2013

By W. V. Mutler

Present day capital costs are analysed for a 2 000 metric tonne per day (MTPD) pyrite burning plant and compared with a sulphur burning plant of the same capacity. Power, raw material and steam production rates are then compared for the two facility types. A sensitivity analysis is conducted to highlight the impact changing sulphur, pyrite, capital and operating costs have on the relative economics of these feeds. Technological improvement effects on capital cost and energy recovery are also discussed. Besides the steam produced from the burning of pure sulphur or pyrite, plants using an advanced form of heat recovery can produce up to 10 bar steam using heat from acid formation. The quantity depends on the overall water balance which is influenced by such factors as gas strength and product acid concentration. Modern materials and innovative process design also improve the ability to increase the high pressure steam from the roaster boiler in pyrite plants above the traditional 1.25 kg of superheated steam per kg of acid produced.

Jan 1, 2009

By G. A. Beiswenger

The application of the law of supply and demand to the sale of crude oil is generally conceded, but the motives underlying the buyer's (refiner's) demands are not always obvious to the seller (producer). In some cases this obscurity has led to the conclusion that the refiner may be unnecessarily particular when he selects one crude and rejects another. This preference, however, is very largely the reflection of the refiner's product demands and the quality of the stocks obtainable from the selected crude. The purpose of this paper is to point out critical characteristies of the major classes of refined products and to show how crudes vary in their suitability for such products. With relatively few exceptions, available processing methods and addition agents make it theoretically possible to produce any type of refined product from any crude source, although it may not be economically sound to do so. The widespread application of thermal cracking for converting higher boiling stocks into gasoline is well known. More recently cracking and refining in the presence of catalysts9 have been developed, as well as various processes for polymerizing lighter hydrocarbons into gasolines having desirable characteristics.6 For several years, selective solvents have been applied commercially to refining inferior quality kerosene, Diesel fuel and lubricating oil distillates.3 Improved methods for refining lubricating oils from crude residual4 formerly suitable only for fuel, are now in use and a number of special solvent processes are available for dewaxing lubricating oils to low pour point.5 These improved refining methods have been developed not only to meet the demand for improved product quality but also to enable the refiner to obtain quality products from crude sources that would not yield such products by the older refining methods. In many cases, the utilization of these modern refining tools necessitates an appreciable expenditure for equipment as well as added manufacturing costs, and their application therefore must be justified economically. Despite the availability of such tools, the added processing costs involved and yields obtainable may render their application entirely impractical. To illustrate this point, inspections of typical cuts from various crudes

Jan 1, 1940

By G. A. Beiswenger

The application of the law of supply and demand to the sale of crude oil is generally conceded, but the motives underlying the buyer's (refiner's) demands are not always obvious to the seller (producer). In some cases this obscurity has led to the conclusion that the refiner may be unnecessarily particular when he selects one crude and rejects another. This preference, however, is very largely the reflection of the refiner's product demands and the quality of the stocks obtainable from the selected crude. The purpose of this paper is to point out critical characteristics of the major classes of refined products and to show how crudes vary in their suitability for such products. With relatively few exceptions, available processing methods and addition agents make it theoretically possible to produce any type of refined product from any crude source, although it may not be economi-cally sound to do so. The widespread application of thermal cracking for converting higher boiling stocks into gasoline is well known. More recently cracking and refining in the presence of catalysts9 have been developed, as well as various processes for polymerizing lighter hydro-carbons into gasolines having desirable characteristics.6 For several years, selective solvents have been applied commercially to refining inferior quality kerosene, Diesel fuel and lubricating oil distillates .3 Improved methods for refining lubricating oils from crude residua,4 formerly suitable only for fuel, are now in use and a number of special solvent processes are available for dewaxing lubricating oils to low pour point.5 These improved refining methods have been developed not only to meet the demand for improved product quality but also to enable the refiner to obtain quality products from crude sources that would not yield such products by the older refining methods. In many cases, the utilization of these modern refining tools necessi-tates an appreciable expenditure for equipment as well as added manufac-turing costs, and their application therefore must be justified economically. Despite the availability of such tools, the added processing costs involved and yields obtainable may render their application entirely impractical. To illustrate this point, inspections of typical cuts from various crudes

Jan 1, 1940

By G. F. Vander Voort

Over the past twenty years, steelmakers have introduced improved practices for reducing the inclusion content of steels. The success of these practice changes can be monitored in a variety of ways. Chemical analysis of the bulk sulphur and oxygen contents provides a relatively simple means to assess the impact of these changes. However, microscopical test methods are still needed to assess the nature of the inclusions present. Traditional chartbased measurement methods have wide acceptability, and their data are well understood by both purchaser and producer for heat acceptance purposes. However, these methods do have inherent weaknesses which limit their usefulness for quality control, SPC, and database applications. Image analysis-based chart measurements are an improvement over manually generated chart ratings, but the data still do not lend themselves to databases and statistical comparisons. ASTM Committee E-4 on Metallography has developed a stereologicallybased image analysis standard test method, E 1245, which provides the necessary data in a form which is easily databased and analyzed statistically. This paper describes E 1245 and shows how data from different heats and melting practices can be compared statistically to ascertain valid test differences.

Jan 1, 1998

By Coates J. R, Firth I. C

The Imperial Smelting Furnace at Cockle Creek, NSW, was constructed in 1961 and is the oldest facility using the Imperial Smelting process in operation. In recent years there have been significant improvements in many areas of the operation, including production, safety, hygiene and environmental performance. Steps taken to achieve these improvements are described. Plans to secure a profitable future while meeting environmental requirements are outlined.

Jan 1, 1993

Ground and air vibrations induced by large surface blasts have been monitored. These field results, as well as a large number of published results, have been used to assess the performance of existing predictors and for the development of improved prediction methods. Field monitoring has been performed, with four seismographs giving complete wave records, at limestone quarries, coal strip mines and an open pit copper mine. Conventional analysis includes least square fitting of peak particle velocities and peak air overpressures with scaled distance formulations. Frequency content has been analyzed, and correlated with blast design (detonation sequence). Two new methods have been developed for predicting ground vibrations induced by blasting. The proposed analytical predictor accounts explicitly for inelastic attenuation and geometrical spreading, and calculates the peak particle velocity as a function of charge weight and distance. Statistical analysis of case studies confirms the consistent improvement over conventional scaled distance predictors. The second new predictor is a computer program simulating blasts, including blast geometry, charge distribution and detonation sequence, and simulating propagation of individual pulses to any point of interest, where effects are summed. A complete blast vibration results, allowing prediction of frequency content and duration as well as peak velocities.

Jan 1, 1983

By Bish Chanda

In the minerals business, like any other commodity-based business, management faces the daily challenge of holding down costs while the real prices of products are continually falling on an inflation-adjusted basis. Since the marketplace sets the prices, often without any premium attached for product quality, being one of the lowest-cost producers is the most viable competitive strategy. Continuous improvement is the mantra that can make the difference in terms of long-term survival of a mining company. Yet, this message has not always been followed, especially during periods of prosperity ushered by high commodity prices. More often than not, the need for improvement is only triggered by a crisis. This may be caused by events such as the onset of a severe economic recession, a prolonged oversupply situation due to an optimistic expansion of capacity during the period of prosperity, or simply falling profits alerting management to bring costs under control. At that time, there would be a need to implement a new cost-saving program, bring in a consultant to find ways to reduce costs, or re-activate an old program that had been shelved for some time.

May 1, 2003

By Douglas A. Bartley, Davey Bickford, Raphael Trousselle

The long awaited arrival of a high accuracy detonator to reach the explosives end user will provide new opportunities the blasting community to become better equipped and able to improve upon the current approaches and methodologies used in blast design as they apply to the mitigation of adverse effects from blasting. This paper will detail the approach and findings throughout a several month research project to quantify the high accuracy detonator benefits and to mitigate a long standing vibration problem at a hard rock stone quarry in the state of New York. The tests conducted in this study were designed to provide important information as to the relationship between the use of high accuracy detonators and overall blast performance in terms of ground vibration prediction, control and improved rock fragmentation.

Jan 1, 1998

By G. A. Beiswenger

The application of the law of supply and demand to the sale of crude oil is generally conceded, but the motives underlying the buyer's (refiner's) demands are not always obvious to the seller (producer). In some cases this obscurity has led to the conclusion that the refiner may be unnecessarily particular when he selects one crude and rejects another. This preference, however, is very largely the reflection of the refiner's product demands and the quality of the stocks obtainable from the selected crude. The purpose of this paper is to point out critical characteristies of the major classes of refined products and to show how crudes vary in their suitability for such products. With relatively few exceptions, available processing methods and addition agents make it theoretically possible to produce any type of refined product from any crude source, although it may not be economically sound to do so. The widespread application of thermal cracking for converting higher boiling stocks into gasoline is well known. More recently cracking and refining in the presence of catalysts9 have been developed, as well as various processes for polymerizing lighter hydrocarbons into gasolines having desirable characteristics.6 For several years, selective solvents have been applied commercially to refining inferior quality kerosene, Diesel fuel and lubricating oil distillates.3 Improved methods for refining lubricating oils from crude residual4 formerly suitable only for fuel, are now in use and a number of special solvent processes are available for dewaxing lubricating oils to low pour point.5 These improved refining methods have been developed not only to meet the demand for improved product quality but also to enable the refiner to obtain quality products from crude sources that would not yield such products by the older refining methods. In many cases, the utilization of these modern refining tools necessitates an appreciable expenditure for equipment as well as added manufacturing costs, and their application therefore must be justified economically. Despite the availability of such tools, the added processing costs involved and yields obtainable may render their application entirely impractical. To illustrate this point, inspections of typical cuts from various crudes

Jan 1, 1940

By C. H. Snyder

The paper deals with details of construction of the Colmol, including improvements in design that will be incorporated in new models. These improvements are results of problems encountered and worked out in experimental operation with the unit. Also included is a descriptive plan of operating where roof and air conditions are of the worst. A summary of production results from the machine is presented.

Jan 6, 1950

The design, construction and operation of a 500,000 tonne per year Carbon-In-Pulp (C.I.P.) plant at Kambalda embracing the period from 1980 to 1982 has been previously discussed (Sceresini, 1982).Since that time the annual throughput rate has increased to 780,000 tpy.This paper discusses the changes and improve-ment made to allow this increased production to occur with minimal capital expenditure.

Jan 1, 1984

By Thomas Fraser

There are large coal reserves in Argentina, Brazil, Chile, Colombia, Peru and Venezuela, and growing productive industries in Brazil, Chile, Peru and Colombia. The paper describes current activities in these coal fields, and improvement programs that are in progress, or are planned. Special emphasis is placed on improvements in mining and preparation practice, and expansion of production that have been accomplished by American equipment and technical assistance.

Jan 4, 1951

By Neil Jagger, Ian Arbuthnot, Mitchell Gordon

Ultra high density underflow is required in many thickener applications and in mineral processing is typically required for tailings to improve the thickened slurry rheology for either tailings dam development or for paste backfill applications. The improved liquid-solid separation resulting from the production ofultra high density underflow has both environmental and process benefits in the gold industry. Additional cyanide is recovered in the thickener overflow thus reducing plant cyanide costs and perhaps more significantly, a reduced quantity of cyanide is discharged to the tailings thus reducing either the toxic effect on the environment or the costs of cyanide destruction. Many gold and other mineral processing plants are situated in arid regions where the cost of water is high and the quantity often very restricted. Ultra high density thickened underflow results in increased recycle of tailings process water to the plant. In Countercurrent Decantation circuits, the wash efficiency is very dependent on the degree of liquid-solid separation in each thickener stage and the benefits ofultra high density underflow are either increased efficiency or decreased equipment costs as it may be possible to reduce the number of stages in the circuit.

Jan 1, 1995

The following papers were presented at the colloquium* on `Mining methods and economics for improved coal extraction, and coal processing and preparation', which was held in Witbank on 3rd and 4th October, 1979. Review of Mining Methods for Improved Extraction of Coal, by P. King, of Gold Fields of South Africa, for¬merly of the Chamber of Mines of South Africa. The Application of Continuous Miners in South African Coal Mines, by J. D. Inch, Bosjesspruit Colliery, I. Brumby, South Witbank Coal Mine Ltd, J. D. Stone, Matla Coal Ltd, and C. J. Beukes, Usutu Colliers Ltd. Longwall Mining Experience at Coalbrook Collieries, by P. G. Henderson, General Mining and Finance Corporation Limited (with a contribution by C. J. Cloete, Sigma Colliery, Sasol I). Pillar Design in Coal Mines, by Dr H. Wagner, Chamber of Mines Research Laboratories. Open-cast Coal Mining at Kriel Colliery, by I. Buchan, L. F. Baars, and C. S. Northcote, Anglo Power Colliery, Kriel Division (with a contribution by M. F. Pleming, General Mining Coal Division). Richards Bay Coal Terminal, by B. Dunne, Richards Bay Coal Terminal. Coal Preparation in South Africa - a General Review,

Jan 1, 1979

By Roger E. Melley

Since startup of the Syncrude Canada Ltd. (SCL) oil sands facility in northern Alberta 15 years ago, numerous improvements have been made in the ore conveying system and equipment. The unique nature of the material conveyed coupled with the wide range of environmental conditions encountered results in a number of unparalleled challenges. Most of the improvements have been brought about through the use of detailed field evaluation. Numerous publications are available that detail the various aspects of conveyor technology, and a significant list of papers are presented each year adding to the knowledge in this field. In the area of power formulae in the mid- 1970s, there were two major sources for use in the design of the SCL conveyors: the Conveyor Equipment Manufactures Association Handbook, 1988, and DIN Specifications 22101: Belt Conveyors for Bulk Materials, 1982. These sources were supplemented by the knowledge of the belt and conveyor equipment vendors and from the general literature. The SCL design was based on the CEMA formula. However, it was accepted that this empirical approach had been developed for use with more conventional materials in more reasonable climates. To accommodate

Jan 1, 1993

Engineering availability of the 120/200 tonne Wabco haulpak fleet at Mt. Whaleback was in the mid fifties and unstable. The project to achieve a reliable 66% during 1980 highlighted "plannable" maintenance, short cycle scheduling, condition monitoring, backlog control, and, above all, the importance of involving all affected people. It is not sufficient for consultants to design systems and make them work. The people who use the system must understand it, support it and "own" it. In this way, they will develop it and improve results after the outside help has been withdrawn INTRODUCTION In early 1979, PA proposed a programme to improve engineering availability of the Mt. Newman Mining fleet of 70 Wabco haulpak trucks of which 53 were 120 tonne and 17 were 200 tonne units. (Subsequently five 200 tonne trucks from Hamersley Iron were added to the fleet). The ore truck workshop was also responsible for 75 tonne trucks used as water trucks and general purpose vehicles. The need for action was clear. The fleet was achieving availability in the "mid fifties" with wide variations indicating that the fleet was becoming unreliable. Projected tonnages required a reliable 66% availability to be

Jan 1, 1982

By Allen M. Newcome

The Ohio valley division of consolidation coal company has incorporated two new aspects within its coal mining concern. A new communication system, thru the cooperation of the c. & p. Telephone company, has been established in each of our mines with its central control in the general office building. In conjunction with this system, a Texas instruments 960 a computer has been incorporated into the system. The purpose for our computer is to provide modernization and improvement to our safety, production and maintenance programs. Thru proper use, the computer will help eliminate inaccuracies and inefficiences that have previously caused inaccurate analysis of problems. Due to federal requirements for more reliable communications in underground mines, Ohio valley division is making a concentrated effort to improve its communication systems. Systems such as the magneto phone and trolley phone have been looked at more critically. It was found that these systems are being used well beyond their limits. With these facts in mind, division personnel started looking for a system that would have these built in advantages: ease of maintenance and installation, increased reliability, low cost, and an inherent ability as a multiple use system.

Jan 1, 1975

In the three years to June 2005, 959 injuries associated with continuous miners (CMs), shuttle cars (SCs), load-haul-dump and personnel transport (PT) were reported by NSW underground coal mines, comprising 23% of all injuries reported. The present paper reports an analysis of the narrative field accompanying these reports to determine opportunities for controlling injury risks. The most common combinations of activity and mechanism were: strain while handling CM cable (96 injuries); caught between or struck by moving parts while bolting on a CM (86 injuries); strains while bolting on CM (54 injuries); and slipping off a CM during access, egress or other activity (60 injuries). For the other equipment considered, the common injury mechanism was the vehicle running over a pothole or other roadway abnormality causing the driver or passengers to be injured (169 injuries). Potential control measures include: monorails for CM services; hydraulic cable reefers; handrails on CM platforms; redesign of CM platforms and bolting rigs to reduce reach distances during drilling and bolting; improvements to guarding of bolting controls; standardisation and shape coding of bolting controls; two handed fast feed; improvements in underground roadway maintenance, vehicle suspension, visibility and seating; and pedestrian proximity warning devices.