Combustion, flame and explosion of gases

Combustion, flame and explosion of gases

Book Review with the bitumen. This paper reports an investigation into the feasibility of selectively concentrating heavy metals, particularly titaniu...

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Book Review with the bitumen. This paper reports an investigation into the feasibility of selectively concentrating heavy metals, particularly titanium and zirconium, from oil sand tailings by the oil phase agglomeration method3-6. The distribution of heavy minerals in the concentrates so obtained was determined by X-ray diffractometry (SCINTAG unit with a graphite crystal monochromator and CoK, radiation; A= 1.7902 A).

Table 2 Mineral composition of various samples as determined from X-ray diffraction Sample

Minerals

1

Major: quartz, anatase, rutile, ilmenite Minor: mica, apatite, pyrite, diaspore (?) Major: quartz, siderite, kaolinite, anatase, calcite, pyrite Minor: rutile Major: zircon, anatase, rutile, quartz Major: zircon, quartz, pyrite

2

3

RESULTS AND DISCUSSION

4

Table 1 lists the elemental analyses of ashes from heavy mineral concentrates and an acid-demineralized (HCl/HF) Syncrude centrifuge tailings sample. The elemental analyses were determined using the quantitative inductively coupled plasma atomic emission spectroscopic method (ICP-AES)‘. X-ray diffraction analyses (Table 2) reveal that gangue rejection is most effective for the sample (No. 3) from Syncrude centrifuge tailings, which consists mainly of zircon, anatase, rutile and quartz. Considering that a portion of the silica is associated with zircon, the amount of quartz in this sample is small. The X-ray diffraction study of the aciddemineralized Syncrude centrifuge tailings sample (No. 4) shows zircon, quartz and pyrite as the major minerals. This result is consistent with the

zircon being most resistant to acid attack. Pyrite was also detected in sample No. 2, but not in samples Nos. 1 and 3. These results demonstrate the advantage of oil phase agglomeration techniques6 in rejecting gangue and other unwanted minerals such as pyrite. They also suggest that titanium minerals could possibly be removed from zircon in the mineral concentrate by acid dissolution. The mineralogical components of the two samples obtained from Suncor sludge pond tailings differ considerably, as shown in Table 2. Since two different modes of agitation were used in collecting these concentrates, these results support the previous observation5 that the mode of agitation plays a significant role in the

beneficiation of heavy metal minerals using oil phase agglomeration techniques. The differences between the mineralogical compositions of the samples obtained from sludge pond tailings and those from centrifuge tailings are representative of the compositions of the feed materials.

REFERENCES Kramers, J. W. and Brown, R. A. S. CIM Bull. 1976,69, 92 Baillie, R. A., Schmoyer, L. F. and Skarada, T. E. Process for Recovering Hydrocarbons and Heavy Minerals from a Tar Sand Hot Water Process Waste Stream. US Patent No. 3990885, 1976 Sirianni, A. F. and Ripmeester, J. A. Can. J. Petrol. Techn. 1981, 131 Majid, A., Sirianni, A. F. and Ripmeester, J. A. Proc. Second World Congress ofChem. Eng. 1981,434 Majid, A. and Ripmeester, J. A. Preprints, Third International Conference on Heavy Crude and Tar Sands Organized by UNITAR 1985,4,2119 Majid, A., Sirianni, F. A. and Ripmeester, J. A. Recovery of Organic and Heavy Metal Components from Aqueous Dispersions. Canadian Patent No. 1200778, 1985 Fassel, V. A. A&. Chem. 1979,51, 1290A Majid, A. and Ripmeester, J. A. Fuel 1986, 65, 1714

Book Review Combustion, Flame and Explosion of Gases Bernard Lewis and Guenther von Elbe Academic Press (3rd edn), 1987, pp. xxiv+739, f52

A book of this title was first published by the authors in 1938. Major revision led to the first edition proper of this famous work, published in 1951, which helped establish the authors as the undoubted leading figures in Combustion Science. The second edition appeared in 1961, with the recognition that the subject was growing at a remarkable pace. The rate of growth during the intervening 26 years between second and third editions has been perhaps even more dramatic, fuelled by biennial Combustion Institute conferences and by journals such as Combustion and Flame (and Fuel, although this was omitted from the authors’ list). One probably cannot expect a complete treatise in a single volume. Similarly, it is no longer possible for one or two specialists, even with the eminence of Lewis and von Elbe, to cover the whole of the field in full comprehension and awareness.

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The aim of this work, as stated in the preface, continues to be to provide ‘the chemist, physicist and engineer with the scientific basis for understanding combustion phenomena’. There is a huge amount of information captured within the text and every combustion scientist should spend some time in its pages. Since the publication of the second edition, however, a growing number of introductory works on the subject have appeared, notably that by Barnard and Bradley, which perhaps make easier teaching texts. For the third edition the authors have steered a middle course between correction of minor changes and a full rewriting. Some parts of the second edition remain virtually verbatim, perhaps augmented only by the addition of a few modern references with a throwaway line in the main text. There has, however, been a major revision of some

chapters and the inclusion of new topics, such as wrinkled flames. The book remains divided into four main sections: part I, Chemistry and Kinetics of the Reaction between Gaseous Fuels and Oxidants; part II, Flame Propagation; part III, State of the Burned Gas; part IV, Technical Combustion Processes. There are also a number of useful appendices, including a short tabulation of some important rate constants (although without any indication of the temperature range over which these may be used). The new edition sees a more attractive typeface and layout, in particular many of the diagrams are larger than before. The authors continue to mix units, for example, kcal or even ft3 h-‘; true SI units are the hardest to find. Part I contains the major revisions. I am disappointed that Thermal Explosion Theory, which has received much attention and interest in the past 30 years, still gets only a cursory mention here and no discussion elsewhere. Chapter II discusses the classic behaviour of the hydrogen-oxygen reaction in great mechanistic detail. The elementary steps

Publications authors seem to regard these (perhaps quite correctly) as a side issue. Again there is little mention of modern flow reactor studies. The new chapter IV, which extends over more than 100 pages, deals with hydrocarbon oxidation. The chance to bring the discussion fully up-todate appears to have been missed. The discussion still revolves around aspects such as the number of cool-flame pulses seen or the dependence of the period between pulses on reaction conditions in vessels. traditional unstirred closed Unfortunately it has been made abundantly clear that such systems are so badly characterized, subjected as they are to thermal gradients and the effects of continuous reactant consumption, that any quantitative matches may well only be fortuitous and even qualitative are not easily responses always interpretable. The best modern studies exploit well-stirred flow reactors which deserve some attention here. Similarly, theoretical attitudes are based on chain-

are still referred to by Roman numerals, whereas there might have been a case for changing to the Baldwin numbering scheme which is becoming adopted widely amongst researchers, to the general good of comprehension and comparison. I am surprised to find no reference to the extensive review of this reaction by Dixon-Lewis and Williams: there is little reference to modern work, beyond that included in the 1961 edition. The authors do not discuss recent work in well-stirred open systems (but I must declare a vested interest here). The emphasis on the effect of the reactor surface still remains from the second edition where modern attitudes and approaches perhaps concentrate more on the homogeneous kinetics. Chapter III, the CO +O, reaction, has been completely rewritten. It is based on a recent, ‘all-embracing’ mechanistic survey by the authors themselves. The discussion of oscillatory glow is rather brief and dismissive for my tastes: the

Publications This section briefly notes relevant books sent to Fuel, with their publication details. Inclusion here does not preclude a critical review at a later date.

Advanced Coal-Use Technology by W. C. Patterson (Financial Times Business Information, London, UK, 1987, ISBN 18533 4 1045 (1935), f180 (UK), f19O/LJS%285 (overseas) ASTM Standards on Viscosity Tables for Kinematic Conversions, Viscosity (ASTM, Philadelphia, USA, pp 42, $18.00 (members $14.40), ISBN O-803 l0990-3)

Received

thermal interpretations, which receive no mention in the text. In part II, some new aspects of flame propagation are introduced, and there is some reference to the active modern field of combustion theory. Chapters V and VI have new material included and VIII, on detonation waves in gases, starts more briskly and contains a discussion of the deflagration to from transition detonation. It is always a problem to revise a classic work, as this book undoubtedly is. One can only have the greatest respect for the authors and their breadth of mastery in this field. Hopefully a new generation of combustors will find the new edition inspirational as others (including myself) have done before. Can we have a paperback version that individuals can afford?

S. K. Scott

Received

Cogeneration: Current Prospects and Future Opportunities, edition 6th (Government Institutes, Inc., Rockville, USA, 1987, pp 272, $68 (USA), $3 and shipping handling (USA)/$S (elsewhere) Specification for Liquefied Petroleum Gus: part 1 Commercial Butane and Propane, part 2 Automotive LPG (BSI, London, UK 1987, part 1 f16.20 (f6.48 to BSI subscribing members) part 2 &ll.OO (E4.40 to subscribing members) Standards of Truining in Safe Gas Installation (Health & Safety Commission, London, UK, 1987, pp 11, ISBN 011 8839667, E4.50)

Proceedings of the Institution of Mechanical Engineers: Internationul Conference on Vehicle Emissions and Their Impact on European Air Quality (Mechanical Engineering Publications Ltd, London, UK, 1987, pp 372, ISBN 085 298 6327, f38 (UK), &48 (overseas)) Socio-Economic und Policy Implicutions of Energy Price Increases, edited by A. Pereira, A. Ulph and W. Tims (Gower, Aldershot, UK, 1987, pp xxiv+317, ISBN 0 566 05520 1, f19.50) Views of Coal Miners in South Africa on Sanctions, by H. Puhe and K. P. Schoppner (Deutsche Afrika-Siftung, Bonn, FRG, 1987, &8.95 (UK)/US $19.50/FF99/13 Rand)

Calendar 12-15 April 1988 Coal and Slurry Technology 13th International Conference Denver, USA Details from: Coal and Slurry Conference Committee, 1800 Connecticut Avenue NW, Washington DC 20009, USA

25-27 April 1988 Gasification - Status and Prospects Conference Birmingham, UK Details from: Institute of Energy, 18 Devonshire Street, London WIN 2AU, UK

2-6 May 1988 Research in Thermochemical Conversion: An International Phoenix, Arizona, USA Details from: Jim Kuester, of Chemical & Bio-Chemical ing, Arizona State University, 85287. USA

17-21 April 1988 Australian Coal Conference Gold Coast, Queensland, Australia Details from: Australian Coal Conference, G.P.O. Box 908, Brisbane, Qld 4001, Australia

May 1988 Unconventional Gas Recovery Symposium Pittsburgh, USA Details from: Society of Petroleum Engineers of AIME, P.O. Box 833836, Richardson, TX 75083-3836, USA

16/17 May 1988 Combustion-Pollution-Reduction: New Techniques in Europe Hamburg, FDR Details from: VDI Society of Energy Technology, PO Box 1139, D-4000 Dusseldorf 1, Germany

Biomass Conference Department EngineerTempe, AZ

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