Absorption, distillation and cooling towers

Absorption, distillation and cooling towers

Experimental Cryophysics. Edited by F. E. HOARE, L. C. JACKSON and N. KURTI, Buttenvorths, London, 1961. xv + 388 pp. 75s. THIS book has nineteen auth...

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Experimental Cryophysics. Edited by F. E. HOARE, L. C. JACKSON and N. KURTI, Buttenvorths, London, 1961. xv + 388 pp. 75s. THIS book has nineteen authors-a number large enough to deter many prospective purchasers who may feel they are paying for many articles that they do not want in order to buy a few that they do. This is a common complaint about books on the theoretical side of a subject but fortunately it is not one that can be made about this book. It is a coherent account of the practical side of the production, maintenance, measurement, history and the use of low temperatures. The first nine chapters are “Low Temperature Laboratories”. “The Mathematics of Gas Liauefaction and Liquefier ~Design” (F. E. HOARE); “Liquid Air Production of Liquid Hydrogen and Helium” @. H. PARKINSON); “Ancillary Equipment for the Production of Liquid Hydrogen and Helium”, “Materials and Methods for the Construction of Low Temperature Apparatus” (A. J. CROFT): “Storane and Transfer of Liauefied Gases” (A. &UER); “Magnetic Cooling” (E. ~WDOZA) and “Low Temperature Thermometry” (R. P. HUDSON). These chapters are a fully documented account of methods used to realize temperatures at and below the boiling point of air. The authors discuss not only the principles of design and the mechanical and thermal properties of the materials of construction, but they also give very many of the more homely tricks-of-the-trade. The advice ranges from the installation of a gas compressor to the silvering of a Dewar vessel. This information is supplemented by 25 pages of Appendices on the physical properties of the relevant gases, liquids and solids. The tenth chapter occupies nearly one quarter of the book and is composed of twelve very short notes on such diverse subjects as calorimetry, X-Ray diffraction techniques and the hydrogen bubble-chamber for the detection of cosmic rays. This part seems leas useful than the more coherent information in the fhst nine chapters. It is interesting to compare this book with another of similar aims and arrange ment, “Physico-Chemical Measurements at High Temperaures” edited by J. G’M. Bocmus and others, and issued by the same publisher in 1959. The earlier book had only one-quarter of its space on general methods and threequarters on specialized equipment. The present reviewer has found more useful the proportions of the later book, since, like many other users, he feels he understands tbe specialized techniques he wishes to use, and can make his own adaptation to low temperatures. It is the advice on the less familiar problems of producing the low temperatures which makes this book so useful.

TI-J~Stext-book sets out to cover the wide field of equilibrium thermodynamics and kinetics at a contemporary final year honours chemistry level. It therefore contains in many ways an increase in available knowledge over other textbooks of a similar character and several topics, previously only available in specialized monographs, are quite succintly treated here. The first 200 pages treat chemical thermodynamic concepts in a fairly classical manner, the writing being of good but not specially original quality. Then follows a useful incursion into statistical thermodynamics of about 50 pages in length. Immediately after this is a well-balanced chapter of 90 pages on adsorption equilibria, followed by a sound, but not particularly practical, exercise of 130 pages on the phase rule. The subsequent chapters on electrolytes, electrolysis and ionic equilibria, (ca. 200 pages) are lucid and informative. At page 690 begins a chapter on reaction kinetics, followed by one on theories of reactions both of which are clear, chemically interesting and calculated to teach-these combine to about 150 pages. Immediately following are chapters on reactions in the solid state, chain reactions, on reactions of species in excited states, on radio chemical kinetics and on kinetics at high temperatures. The material contained in the chapters on kinetic phenomena has often been drawn from recent journals and monographs, and is well presented and well converted to the needs and abilities of a good honours student. The last 80 pages of text is devoted to the quantum theory and contains a good coverage of notions leading to an understanding of chemical binding. This chapter seems rather an intellectual make-weight. The books finishes with an explanation of its symbology and comprehensive indexes. This volume is good value at leas than Id. per page and might well supplant some of the older long text books in physical chemistry. It has not been given a suiliciently comprehensive range of topics to do battle with the doyen of these but it shows clearly that the day of the long text book is not yet over. The book is certainly to be commended to students of chemistry; chemical engineering students will find it less valuable under current syllabuses Many young chemical engineering scientists researching in borderland territory would discover in this a comparatively readable and useful basic reference text and I feel sure that libraries will find this book well used. J. C. McCouax~~

J. S. ROWLINS~N W. S. NORMAN: Absorption, Dlstlllatlon and Cooling Towers. Longmans, Green, London, 1961. 477 pp., 70s. DR. NORMAN’Sbook is addressed both to advanced students J. ROSE: Dynamic Physical Chemistry. pitman & Sons, and research workers, and to practising chemical engineers. London, xii + 1-1218 pp., 75s. The object is to tell the former something about the practical

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Book Reviews ends to which research work should be directed, and to give the latter some realisation of the contributions which research can make to their art. In addition, the first five chapters give the standard text-book treatment of transfer processes and design calculations, in a form suitable for undergraduate teaching. This section is well-presented, although not markedly different from the treatment given in a number of other books. As regards the presentation of research and theory, the author has been diligent in collating the literature, and gives over 500 references (almost exclusively to publicatio;in the English language). The book can, from one point of view, be regarded as a bibliography of the British and American literature and as such will be of great value to research workers. In general the author has been content to present summaries of the publications to which he refers without much in the way of criticism or connecting discussion. Some of the material thus reported without comment is in fact wrong or misconceived. For instance, in the chapter on “Absorption with Chemical Reaction” the only value given for the rate-constant of the reaction between COs and OH- is that of HIMMELBLAU and BABB, which is about a hundred times greater than the values found by a number of other workers and is clearly wrong; while the references to the absorption of COs in ethanolamines present a quite erroneous view of the reaction mechanism and ignore the work of FAURHOLT. With regard to the presentation of practical aspects of the matter to the research worker, there are a number of ilhnninating passages discussing the factors which in practice determine the design of equipment, and quoting typical dimensions, flow-rates and performances. The amount of money spent on chemical engineering research in universities is substantial, and it is important that research workers should continually ask themselves whether their work will make any useful addition to the practical engineer’s knowledge. The author’s efforts in this direction are praiseworthy. One. must mention also the large number of worked examples which are a valuable feature of the book, whether regarded as exercises for students or illustrations of applications of the design theories. All told, this will prove a useful book in many ways. Although not a particularly reliable guide to the more difficult theoretical aspects of the subject, it is a very valuable compendium of information to have assembled in a single volume. P. V. DANCKWER~

B. TEPPER, HARRIETL. HARDY and R. I, C~UMBERLIN: ToxIcitv of Bervllhun Comwunds. Elsevier Publishing Company, 1961. ‘20s. THE low density of beryllium, its high modulus of elasticity, high melting point, good thermal conductivity and corrosion resistance, have led to its use in the aircraft and space vehicle industries. Research into its employment as a structural metal has continued, although here its low ductility is a handicap, and there are still difficulties to be overcome in the joining together of metallic parts. In the finely divided state beryllium may prove to be a useful rocket fuel. The metal’s ability to yield neutrons under bombardment by alpha particles, and to moderate neutron activity has been applied in the use of atomic energy. Beryllium oxide, because of its stability and high thermal conductivity, is increasingly employed in the manufacture of crucibles, rocket motor parts and nose cones, and also of special refractories. An acute illness in beryllium workers has occurred, taking the form of bronchitis or pneumonitis. Skin contact with beryllium salts may lead to dermatitis, and also to eye irritation due to conjuctivitis. The chronic form of the disease affects the hmg and other organs of the body, and is often characterized by shortness of breath and loss of weight. There has been a mortality rate of approximately 34 per cent in this form of illness, treatment so far being only partially successful. Much emphasis must therefore be placed on preventive measures. With the exception of beryl ore, all materials containing beryllium are potentially hazardous, and careful design of plant and of equipment used in handling these substances is essential. All personnel must be trained in the use of protective measures and in the maintenance of a very high standard of plant hygiene. Neighbourhood air pollution from stacks and other sources must be prevented, and workers cannot be allowed to take home contaminated clothing. The authors have been successful in assembling in a small volume all the chief facts now known concerning beryllium toxicity. The metal and its compounds have special qualities which make their preparation increasingly desirable. It is of great importance therefore that those handling these materials should inform themselves in time of the potential hazards, and guard against them. Fortunately, as this book makes clear, there is excellent reason for believing that work with beryllium can be carried out in entire safety provided the necessary precautions are taken. T. G. FAULKNERH~JD~~N

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