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By D. W. Gunkle

Processing of various ores and materials in a reducing atmosphere has been done for many years. However, the typical device currently used is a large, often high maintenance, expensive piece of equipment; the rotary kiln. While it is a very reliable and a proven technology, the rotary kiln also has its limitations. It is limited by its ability to process very fine materials without creating a huge dust loss to the air pollution control equipment. This leads us towards the development of an alternate technology; the Gas Suspension System. Gas suspension preheating of various materials has been in commercial use since the early 1950's, but recently has been expanded to include Gas Suspension Reduction. Laboratory experience has proven successful on several materials; Nickel Laterite Fines, Iron Ore Fines, Fluorspar, and Clays. The gas suspension reduction system has many advantages over the conventional reduction kiln when processing fines. They are; lower cost, more fuel efficient, able to process fines, less real estate required, etc.

Jan 1, 1998

By M. Van Hecke, Y. Berube, L. M. de Smecht

Nitrogen solubilities in water at 100, 200, and 400 psi, in the temperature range 100 to 175C, were determined using an automated system involving flash evaporation and gas chromatography. Rates of gas transfer into a standard laboratory auto-clave were measured by the same technique. The rates at which a gas can dissolve into such a reactor were found to be close to the rates of oxygen consumption observed during the oxidation of several mineral sulfides, indicating that gas transfer might be a rate-limiting step in autoclave leaching.

Jan 1, 1977

By B. L. Moreau

Certain gas wells tend to form hydrates in the production tubing. This paper outlines a method developed and used by the Author's company to overcome the problem. The injection of glycol to control hydrates results in sufficient dehydration to allow the gas to be trans-ported through a field-gathering system b a treatment plant. Sub-surface injection of glycol also offers a method of introducing corrosion inhibitors into the gas stream. The major operating difficulties have been overcome and the system is now in use in the northeastern part of British Columbia.

Jan 1, 1958

Gas well tests were performed on 17 wells in the Roma area. The procedure used in the test programme incorporates an initial isochronal test followed by what is described as the "two flow drawdown" technique. The second flow of the two flow drawdown test was conducted for sufficient time to allow transient investigation of the surrounding reservoir. This combination of tests allows the evaluation of stabilized production capacity in addition to the determination ,of several important reservoir characteristics.It also provides a qualitative indication of reserves, by reflecting the presence or absence of reservoir boundaries within the drainage area affected during the test.

Jan 1, 1968

By AIME AIME

A discussion of the Papers by Prof. H. Hubert, Liege, Belgium ; Mr. Tom Westgarth, Middlesbrough, England ; and Mr. K. Reinhardt, Dortmund, Germany, presented at the London Meeting, July, 1906, and printed in Bi-Monthly Bulletin, No. 12, November, 1906; pp. 910 to 930, 971 to 987, 1037 to 1163. MR. ADOLPH GREINER, Seraing, Belgium :-I have nothing special to add to Professor Hubert's paper except to say that there are some little things that it would be well to have cor-rected when the paper comes to be published. In dealing with the thermal efficiency of the engine, you will find that the 29.84 per cent was a very high one. Professor Hubert has forgotten those engines built under the Cockerill type, but he has referred to them in Appendix II. At our works at Cockerill we have built 63 engines, giving 63,000 h.p., and the other companies who have received licenses have built 113 engines, making 103,000 h.p., and aggregating 176 engines and 166,000 h.p. Eight years ago I had the pleasure of giving to the Institute the results obtained up to that time. Since then a good many engines have been constructed. In 1898 I thought a blast-furnace producing 100 tons of pig iron would allow 3,000 h.p. Professor Witz and Professor Hubert show that with the same production of pig the new engines take 3,800 h.p. out of the gas. At present at Cockerill we make 700 to 800 tons of pig iron per day, and we hope to have 26,000 h.p; in a few years. At present we have only half of that in gas-engines, but we hope to have in five or six years all the gas out of these furnaces to the number of 25,000 or 26,000 h.p. MR. Tom WESTGARTH, Middlesbrough, England:-My contribution is not a paper in the ordinary sense of the word, because I am sure you will agree with me that what I have written is only supplementary to the other two papers. The notes are schedules of the larger-size gas-engines built by the engine-makers, of 500 h.p. and upwards. If you look at the schedules you will find that in England gas-engines have be-

Jan 1, 1907

By G. H. Agnew

When water floods are initiated after gas-oil ratios have increased, the transition period from the start of injection until" the gas-oil ratios are returned to the solution gas-oil ratio may be important for either economic or technical reasons. The transition period is longest, and consequently most critical in water floods where injection is equal to withdrawals. This paper describes a theoretical basis for predicting the behavior of such a system and outlines a procedure for making the necessary calculations. The calculation procedure is illustrated for two actual cases: a line drive water flood and a five spot water flood. In each case there is a reasonable similarity between the actual and calculated performance.

Jan 1, 1960

By F. W. Lake

The ultimate production from a natural reservoir of petroleum is inversely proportional to the gas-oil ratios existing during the producing life of the reservoir whenever gas is the major expulsive force in the recovery. In other words, in the period during which gas is the major expulsive force the ultimate production will be increased if the gas-oil ratio is decreased, and vice versa. This condition prevails in the greater number of the present producing districts. While this relation is difficult to prove from actual operation, on account of the present paucity of detailed observations, it must be admitted after a study of the forces and conditions governing the recovery of petroleum from natural reservoirs. Where gas and oil exist under pressure in sand interstices and water movement is not freely possible, the force expended in moving the oil to the well is the expansion and movement of the gas through the pressure differential existing between the interior of the reservoir and the well. If pressure and solution conditions in the untapped reservoir are such that the relation between gas and oil volumes at atmospheric conditions is as 100:1; and if during the producing period, until the gas is exhausted, the relation between the gas and oil volumes produced is 300:1, it follows that only one-third of the oil has been produced and the remaining two-thirds cannot be recovered unless some extraneous force is introduced into the reservoir. This serves to illustrate the importance of gas-oil ratio control during normal producing operations. Gas-oil Ratio Control Eliminating natural conditions in a reservoir, which govern gas-oil ratios, such as the physical properties of the oil and gas, the physical characteristics of the reservoir strata and the original pressure and solution conditions in the reservoir, which cannot be controlled by operation practice; and also eliminating operating conditions that apply to the reservoir as a whole, such as well spacing, well locations, relative completion dates, various penetrations and drilling practice; there remains but one condition in each well that influences the gas-oil ratio and that is

Jan 1, 1928

By L. D. van Dyk

The extraction of iron and lead from their oxides with a volatile organic ligand such as acetylacetone in the gas phase offers potential advantages of lower energy consumption, recycling of the extractant, recovery of pure metals, and a reduced environmental impact compared with conventional extraction processes. The influence of reaction temperature, ligand flow rate, and metal oxide levels on the extraction and rates of reaction of iron and lead from single metal oxide (synthetic haematite (Fe2O3) and synthetic massicot (PbO)) systems in a fluidized bed was studied. It was found that at the investigated acetylacetone flow rates, the influence of mass transfer was limited, but that the reaction suffered from reactant starvation. When the metal load increased the effect of starvation on the rate of reaction also increased. The reaction kinetics increased with an increase in temperature for both systems. At low metal oxide concentrations more that 80 per cent of the iron and lead could be extracted from their respective metal oxides after only four hours.

Jan 1, 2012

By L. D. van Dyk

The extraction of iron and lead from their oxides with a volatile organic ligand such as acetylacetone in the gas phase offers potential advantages of lower energy consumption, recycling of the extractant, recovery of pure metals, and a reduced environmental impact compared with conventional extraction processes. The influence of reaction temperature, ligand flow rate, and metal oxide levels on the extraction and rates of reaction of iron and lead from single metal oxide (synthetic haematite (Fe2O3) and synthetic massicot (PbO)) systems in a fluidized bed was studied. It was found that at the investigated acetylacetone flow rates, the influence of mass transfer was limited, but that the reaction suffered from reactant starvation. When the metal load increased the effect of starvation on the rate of reaction also increased. The reaction kinetics increased with an increase in temperature for both systems. At low metal oxide concentrations more that 80 per cent of the iron and lead could be extracted from their respective metal oxides after only four hours.

Jan 1, 2012

By A. D. Pienaar

The aqueous chemistry of niobium and tantalum compounds with hydrofluoric acid is a mature field of investigation. In contrast, very little attention has been paid to reactions of these compounds in non-aqueous environments. Similarly, reactions of elemental fluorine with niobium and tantalum compounds have received little more than cursory attention in literature. This work discusses the isothermal reaction kinetics derived from thermogravimetry, using a less redundant approach than is currently the standard. We also discuss the most likely kinetic models for this reaction.

Jan 1, 2012

By A. D. Pienaar

The aqueous chemistry of niobium and tantalum compounds with hydrofluoric acid is a mature field of investigation. In contrast, very little attention has been paid to reactions of these compounds in non-aqueous environments. Similarly, reactions of elemental fluorine with niobium and tantalum compounds have received little more than cursory attention in literature. This work discusses the isothermal reaction kinetics derived from thermogravimetry, using a less redundant approach than is currently the standard. We also discuss the most likely kinetic models for this reaction.

Jan 1, 2012

By Samuel S. Wyer

THE installation of the gas-producer power-plant in America has been so unusual that all engineers have viewed it with in¬terest; a large majority, however, regard it with a lack of con-fidence and many with positive distrust. Despite the fact that European engineers have usually been less inclined to take the initiative along experimental lines than are Americans, they have, nevertheless, developed the gas-producer plant to a very high state of efficiency to which they were forced by the neces¬sity of economy in fuel-consumption. The gas-producer power-plant is so common in Europe that engineers as well as the general public regard it with the same degree of confidence that is now universally placed in steam¬plants. Gas-engines, both small and large, are in general use there, and central stations, aggregating several thousand horse¬power, are quite numerous. The fact that gas-producer power-plants have received so little attention in America may be attributed to five conditions:-1', ignorance and prejudice; 2, newness of work; 3, in-

Mar 1, 1905

By Tateo Usui

In the course of carbonization of coal under a rising temperature condition, volatile matter (V.M.) is released. The kind and amount of V.M. released depend on the kind of coal. Components of V.M. are tar, hydrocarbons (CH4, C2H4, C2H6, C3H8), CO, CO2 and H2, which are released in this order as a function of carbonization temperature. When the carbonization of coal under a rising temperature condition is interrupted at a certain temperature, TC, max, semi-coal-char with residual V.M. is obtained. If some optimum interruption-temperature is chosen, small but most suitable amount of V.M., namely H2, is retained. When the semi-coal-char thus obtained is heated again under the same rising temperature conditions but up to more than TC, max (1), the residual V.M. is released from just around TC, max (1). We propose novel iron ore agglomerate bearing such semi-coal-char with some strength. While simple iron ore agglomerate bearing coal char will start the reduction reaction as solid-solid reaction at somewhat higher temperature, the proposed one will start the reduction reaction as gas-solid reaction at somewhat lower temperature but a little higher than TC, max. Samples of semi-coal-char and novel iron ore agglomerate bearing such semi-coal-char have been prepared and evaluated.

Jan 1, 2006

By Ricardo Morales

Reactions between solids and a gas phase have many interesting theoretical aspects as well as technological applications. The present group had carried out experimental investigations as well as theoretical studies of a number of gas-solid reactions over the past decade and was able to derive interesting results. Studies of the decomposition of alkaline earth carbonates were carried out by thermogravimetric analyses. The experiments were carried out using thin powder beds as well as iso-statically pressed compacts with thermocouples embedded in the same. The investigations revealed the complexity of the reactions and the impact of the heat- and mass transfer aspects on the reaction kinetics. In the case of BaCO3, the kinetics of decomposition was complicated by the formation of a liquid phase. In the case of SrCO3, the reaction kinetics could be simulated by theoretical modeling. Gas-solid reactions were also employed as a versatile process tool towards the production of alloys and intermetallics involving transition elements by hydrogen reduction of complex oxides involving transition metals. Thin powder beds were employed to examine the micro-kinetics, while fluidized bed technique was utilized to produce bulk alloys. Preliminary correlations could be drawn between the thermodynamic stabilities of the oxides and the activation energies of chemical reduction steps. Adjusting the process parameters, products at nano-scale could be produced. The structural, mechanical and thermal properties were investigated in the case of these products. The potentialities of this method as a green route to produce industrially important alloys and intermetallics with unique properties are demonstrated.

Jan 1, 2006

By Herbert H. Kouns, Harlan W. Nelson, Bruce O. Buckland

GASIFICATION of coal under pressure produces a gas that may be used as the fuel in a gas turbine. The pressure produced by a gas-turbine compressor (5 to 9 atm) should allow the use of high firing rates without unreasonably high solid carry-over rates. Hot make-gas with the tars contained in it in the vapor form can be used in a gas turbine. Most of the ash can be removed through a grate, and only a small portion of the ash and any of the solid combustible material carried over by the make-gas requires separation. The gas stream from which separation is required is a small portion of the total flow of a gas-turbine plant and hence the separator size will be small. The gas stream is reducing and will not, therefore, allow separator fires to occur. The response of the producer to rapid load changes is satisfactory. Only the air rate must change substantially in synchronism with the load. The coal feed, the steam addition to the blast, and the ash-removal rate can follow the load changes with time lags in the order of minutes. The necessary control equipment is simplified by these producer characteristics. With these possibilities in mind, the Steam Turbine Division of the General Electric Co. made arrangements with Battelle Memorial Institute in January 1945 to investigate the problems of the gasification process. A number of tests were made during this investigation on an updraft producer with a grate area of 1 sq ft. The equipment used has been described and the results of the tests made between 1946 and 1950 have been reported.1 The testing with this small producer was recently completed. The concluding tests were run to determine the effectiveness of a clinker-grinding grate and the effect of the operating conditions on the amount and character of the solid carry-over. The present paper describes the producer as modified, and gives the results of the tests using three coals. Another method of using coal in gas turbines is to pulverize it and burn it directly in the combustion chambers. This plan is being tried by the Loco- motive Development Committee of the Bituminous Coal Research, Inc., whose investigation has reached the stage of tests of full-sized equipment.

Jan 1, 1953

By Clinton M. Young

(Pittsburg Meeting, March, 1910.) I. INTRODUCTION. THE experiments herein. described were carried on in 1908-9 . by the State Geological Survey of Kansas. Some months before taking up work on black powder the Survey had resumed work on an interrupted investigation of explosions in coal-mines, a subject which is engaging the attention. of numerous investigators. An unusual number of serious disasters has directed to. the subject a study which discloses the disquieting fact that, in the. United States, the ratio of lives lost per ton of coal mined has been on the increase. Methods of coal-mining have changed to some extent with the great increase of output, attained in, comparatively recent years. These changes involve the working of very extensive mines, with increased difficulty of ventilation, increased accumulation of coal-dust, and. a very great increase in the amount of explosive used.. . This last point assumes truly startling proportions when it is carefully observed. In the fields of the Middle. West it is not now uncommon for a miner to use six ,kegs (150 lb.) of black powder in a "pay" of two weeks, while within the memory. of men still active, one keg (25 .lb.) would last two men for a " pay." So. great has . the use of explosives become in some fields that the skilled coal-miner is hard to find, and the coal is not mined, but blasted. A preliminary study of the subject. of explosions in coal-mines has. led to the belief . that the use of, large -quantities of explosives, in some cases by slightly-trained men, had not been * Associate Professor- of Mining Engineering, University of Kansas, Lawrence, Ran.

Aug 1, 1910

By Y Zhang, X Yi, J Deng, J Zhao, J Song

To obtain the combustion process of a coal fire, a high-temperature programmed system is used to simulate the spontaneous combustion process of fresh and weathered coals. Both fresh coal and weathered coals from Liulingou, Inner Mongolia, China, were used to examine the gas releases from constant temperature to 650°C. Moreover, gas release rate was used to calculate the characteristic temperatures. The results showed the coal samples lasted to oxidise under high temperatures, and released plenty of heat to assist self-heating. The humic acid contained inside the weathered coal went through thermal decomposition as temperature rising and generated gases. This resulted in increasing concentrations of CO, CO2, CH4, C2H4, and C2H6. Changes of CH4, C2H4, and C2H6 gases were also similar. For weathered coal, concentrations of three gases were kept in balance under low temperatures, increased rapidly with the temperature rising. After the ignition temperature, the concentration of hydrocarbon was reduced. In addition, particle size affected coal spontaneous combustion. Coal samples with less than 0.9 mm in size produced much more CO than others. This study has examined coal spontaneous combustion caused by coal weathering during mining and its impacts on self-heating and pyrolysis in the process.CITATION:Deng, J, Song, J, Zhao, J, Zhang, Y, Yi, X and Zhang, Y, 2017. Gaseous products of weathered coal during the process of spontaneous combustion, in Proceedings Australian Mine Vent Conference 2017, pp 79–84 (The Australasian Institute of Mining and Metallurgy: Melbourne).

Aug 28, 2017

By Baojun Zhao

Primary lead production using the lead blast furnace in conventional practice is carried out using sinter feed. At YMG, China, the sinter plant has been replaced with a lead ISASMELT furnace. The ISASMELT furnace produces lead bullion plus a high-lead slag, which is cast into lumps to provide a suitable feed for the blast furnace. In the present study the relative microstructures and reduction characteristics of industrial lead sinters and synthetic ISASMELT slag in CO/CO2 gas mixtures have been measured and compared. The microstructure and property changes, and the mechanisms of reduction in each case are examined and discussed. The results of the study are used to explain the successful implementation of cast slag feed in commercial ISASMELT- lead blast furnace practice. Key words: lead slag, lead sinter, lead blast furnace, reduction kinetics and mechanisms

Jan 1, 2008

By T. A. Larssen

The efficiency in production of manganese ferroalloys is dependent on the gaseous reduction of the higher manganese oxides in the ores used as raw materials. The materials, descending in the furnace, will meet the furnace gas that contains significant amounts of CO(g) and reduce in subsequent steps, the last step being reduction of Mn3O4 to MnO. This step may to varying extent occur at temperatures exceeding 800 °C, i.e. in the active region of the Boudouard reaction. The gas reduction of Assmang and Comilog manganese ores were investigated in CO-CO2-atmosphere at temperatures up to 1000 °C. It was seen that decreasing ore size correlates to a lower reduction temperature and increasing reduction rate. Similar effect was observed with increasing CO-content in the gas atmosphere. Further, it was found that Comilog ore obtained a complete prereduction at 600 °C, whereas reduction of Assmang ore was not complete at 800 °C for the majority of the experiments.

By N. A. Ziegler

THE present publication is a continuation of the work on gas analysis, described in a paper presented before the Institute of Metals Division a year ago.1 While that paper was largely descriptive in character, dealing with the various parts of the apparatus and method of operations, the present one gives numerical data obtained as a result of a series of experiments with iron-carbon alloys. The apparatus and the methods applied are essentially the same as previously described, changes being only in minor details. Attention should be called to the fact that in the present work we are dealing with the gaseous mixtures obtained as a result of vacuum melting of various ferrous alloys. It should be understood that when the terms "degasified sample" and "products of degasification" are used, they refer to the sample remaining after the vacuum fusion of the alloy and the gaseous products removed therefrom, respectively. The writer does not wish to create the impression that the metallic products of this process are absolutely free from any gaseous elements, nor that the gases obtained are present as such in the original sample. These two points are not yet definitely known and are subjects for future investigation. The point, however, which has been established beyond doubt, is that all the gases dealt with come from the metallic charge and are present either in the charge as such, or are produced as a result of chemical reactions going on within the charge. The suggestion that the gases are due to the reactions between the metallic charge and the refractory materials has no valid basis.

Jan 1, 1929