- Email: [email protected]
Membrane separations in biotechnology
The Chemical
Engineering
Journal,
38 (1988)
B13
- B16
B13
Book Reviews
Membrane Separations
in Biotechnology
edited by W. Courtney McGregor; published by Marcel Dekker, New York, 1986; 386 pp.; price, U.S. $78.00
Membrane operations are appearing in more and more processes every year. The growth of 10 - 20% per annum in turnover of the membrane companies has to be seen in the background of relative stagnation of the processing industries as a whole and it is certain that these operations show consistent advantages over earlier separation techniques. Naturally they have become most established in a relatively small number of fields where they have almost taken over completely from the traditional techniques, whilst in other areas there has been only token penetration. The membrane operation offers clear advantages of containment and energy savings over the competition. There have been difficulties in using membranes and early reliability problems perhaps left lingering doubts which have not been fully dispelled. Membranes used to have short lifetimes and were difficult to clean. Nowadays five year lifetimes are common in desalination plants, whilst one year guarantees are the rule in most applications. Membranes are now more robust, made of stronger materials, less liable to severe fouling, have better quality control and have taken their place as part of the armoury of the process engineer. Applications are most common in the water industry for both brackish water desalination and waste-water recycling. The food and bioprocessing industries and medicine are also avid users of membranes. The largest single market for membranes is in dialysis, principally because these membranes are virtually single-use applications. New processes using membranes are continuing to grow and take over as in fruit juice processing where evaporators are being rapidly superseded both on grounds of energy costs and on finished product quality. The world leaders in membrane technology are the Americans because of the boost given to their domestic membrane industry by the
Office of Saline Water programme in the 1960s. Now, however, the Japanese are carrying out more research with a ten year programme directed at new technology from the membrane, through new systems, to novel applications. The programme is now in its sixth year and already the Japanese are beginning to be the dominant force in the technology. Interestingly this American book appears scarcely aware of Japanese work or membranes, nor does it mention except in the briefest detail the technique of pervaporation which has been developed in Europe and researched here and in Japan. Yet to appear on the scene are the Chinese who have proposed spending over the next five years an amount equal to the world membrane market in 1983. In the face of all this the U.K. has a small directed research initiative in the SERC and DTI with a small number of active companies. Little advantage is taken of membranes by the U.K. user and most of the domestic production is exported. This collection of articles edited by McGregor is a useful primer for those thinking of using this technology in th,e bioprocessing field. It describes the successful use of membranes in a variety of areas and also gives some rudimentary theory. The book is a valuable example of a multiauthored commissioned work on a specialised topic. The contributions (six academic, four industrial) give practical information on the use of membranes in the food and fermentation industries. It is claimed that a major purpose of the work is to provide feedback from satisfied membrane users in order to encourage the less daring. The authors, when considering fundamental aspects of membrane filtration, appear not to be aware of a great deal of work on fouling of ultrafiltration and microfiltration operations that has been appearing in Europe over the past few years. Several of the chapters on practical systems are short and trivial but then there are a few of great value. A review of membrane reactors by Cheryan and Mehaia is well prepared and covers 95 references up @ Elsevier
Sequoia/Printed
in The Netherlands
B14
to 1982 with a handful of later references, mostly by one of the authors. No detailed analysis of membrane reactors is presented. Kosikowski presents a very thorough chapter on membranes in food processing mostly based on the dairy industry and including detail of the newer processes. As a report on the successful use of membranes it is most encouraging to potential users since it demonstrates that the processes are no longer experimental. Leonard’s chapter on artificial organs presents material that has normally been seen only in the medical literature. Remaining in the medical area, two chapters on blood separation give useful data on electro-dialysis processing of blood and on plasma fractionation. The articles present details of a tested technology for plasma treatment. In removing salts from plasma the salts are washed out by diafiltration which must occur at an optimum concentration of protein to minimise total processing time. The clean protein can then be ultrafiltered to its final concentration. Cell harvesting is an area where membranes are currently used but there is little quantitative material available except for pilot scale trials. Some more such information is given with correlations which allow extension to large scale system design although the author, Hamisch, does not claim that this information is based on successful experience. In this chapter it is irritating to have a mixture of flux units varying from lme2 d-l, through U.S. gal ft-” d-’ to kg min-‘/cartridge. It is also irritating that membrane types are not always fully described as to material or at least manufacturer’s code. In spite of these minor complaints the book is well worth using by those thinking of applying membrane operations in the food or bioprocessing industries, or in medical applications. J. A. HOWELL
Advanced
Biochemical
Engineering
edited by H. R. Bungay and G. Belfort; published by Wiley Interscience, New York, 1987; 300 pp.
In pharmaceutical and agrochemical biotechnology, only two or three of the recentlyformed biotechnology companies will survive
into the 1990’s, and most work will be confined to established drug and chemical companies. This is a prediction put forward in the forthright and penetrating overview of biochemical engineering which forms the opening chapter of “Advanced Biochemical Engineering”. This is, on the whole, an excellent book, stemming from the summer school on biochemical engineering at Rensselaer Polytechnic in New York. While most are academics, two of its ten contributors are from industry. The book emphasises the importance of a thorough understanding of the biosciences as well as the quantitative engineering aspects, a particularly valuable approach in an area as subject to bandwaggoneering as biochemical engineering has been. There are three excellent chapters on applied genetics and molecular enzyme engineering which deal with the subjects concisely, but avoid getting bogged down in the morass of acronyms and esoteric jargon by which accounts of these topics are all too often obfuscated. Recent developments in controllable expression vectors will be of particular interest to biochemical process engineers, but it would have been useful to have a more detailed account of yeast transformations in general, in view of the intense current interest in these organisms. On the engineering side, most attention has been given to separation processes, with excellent accounts of sorption and membrane processes. An overview chapter on product recovery, while very good as far as it goes, in fact concentrates on coagulation and filtration, and other processes which undoubtedly qualify as “advanced” are dealt with only briefly. As the whole book has only 300 pages, it would have been worthwhile making room for a chapter giving detailed coverage of chromatography and partition. The book would also be improved by inclusion of an in-depth treatment of fermentation processes, particularly the recent advances in fermentation control. A chapter on computer modelling of bioreactor performance by a professor of mechanical and aerospace engineering contains the remarkable statement, “Enzymes resemble synthetic chemical catalysts” with no further explanation. The account given of the topic is confusing, as equations are stated with little explanation of the assumptions on which they are
Engineering
Journal,
38 (1988)
B13
- B16
B13
Book Reviews
Membrane Separations
in Biotechnology
edited by W. Courtney McGregor; published by Marcel Dekker, New York, 1986; 386 pp.; price, U.S. $78.00
Membrane operations are appearing in more and more processes every year. The growth of 10 - 20% per annum in turnover of the membrane companies has to be seen in the background of relative stagnation of the processing industries as a whole and it is certain that these operations show consistent advantages over earlier separation techniques. Naturally they have become most established in a relatively small number of fields where they have almost taken over completely from the traditional techniques, whilst in other areas there has been only token penetration. The membrane operation offers clear advantages of containment and energy savings over the competition. There have been difficulties in using membranes and early reliability problems perhaps left lingering doubts which have not been fully dispelled. Membranes used to have short lifetimes and were difficult to clean. Nowadays five year lifetimes are common in desalination plants, whilst one year guarantees are the rule in most applications. Membranes are now more robust, made of stronger materials, less liable to severe fouling, have better quality control and have taken their place as part of the armoury of the process engineer. Applications are most common in the water industry for both brackish water desalination and waste-water recycling. The food and bioprocessing industries and medicine are also avid users of membranes. The largest single market for membranes is in dialysis, principally because these membranes are virtually single-use applications. New processes using membranes are continuing to grow and take over as in fruit juice processing where evaporators are being rapidly superseded both on grounds of energy costs and on finished product quality. The world leaders in membrane technology are the Americans because of the boost given to their domestic membrane industry by the
Office of Saline Water programme in the 1960s. Now, however, the Japanese are carrying out more research with a ten year programme directed at new technology from the membrane, through new systems, to novel applications. The programme is now in its sixth year and already the Japanese are beginning to be the dominant force in the technology. Interestingly this American book appears scarcely aware of Japanese work or membranes, nor does it mention except in the briefest detail the technique of pervaporation which has been developed in Europe and researched here and in Japan. Yet to appear on the scene are the Chinese who have proposed spending over the next five years an amount equal to the world membrane market in 1983. In the face of all this the U.K. has a small directed research initiative in the SERC and DTI with a small number of active companies. Little advantage is taken of membranes by the U.K. user and most of the domestic production is exported. This collection of articles edited by McGregor is a useful primer for those thinking of using this technology in th,e bioprocessing field. It describes the successful use of membranes in a variety of areas and also gives some rudimentary theory. The book is a valuable example of a multiauthored commissioned work on a specialised topic. The contributions (six academic, four industrial) give practical information on the use of membranes in the food and fermentation industries. It is claimed that a major purpose of the work is to provide feedback from satisfied membrane users in order to encourage the less daring. The authors, when considering fundamental aspects of membrane filtration, appear not to be aware of a great deal of work on fouling of ultrafiltration and microfiltration operations that has been appearing in Europe over the past few years. Several of the chapters on practical systems are short and trivial but then there are a few of great value. A review of membrane reactors by Cheryan and Mehaia is well prepared and covers 95 references up @ Elsevier
Sequoia/Printed
in The Netherlands
B14
to 1982 with a handful of later references, mostly by one of the authors. No detailed analysis of membrane reactors is presented. Kosikowski presents a very thorough chapter on membranes in food processing mostly based on the dairy industry and including detail of the newer processes. As a report on the successful use of membranes it is most encouraging to potential users since it demonstrates that the processes are no longer experimental. Leonard’s chapter on artificial organs presents material that has normally been seen only in the medical literature. Remaining in the medical area, two chapters on blood separation give useful data on electro-dialysis processing of blood and on plasma fractionation. The articles present details of a tested technology for plasma treatment. In removing salts from plasma the salts are washed out by diafiltration which must occur at an optimum concentration of protein to minimise total processing time. The clean protein can then be ultrafiltered to its final concentration. Cell harvesting is an area where membranes are currently used but there is little quantitative material available except for pilot scale trials. Some more such information is given with correlations which allow extension to large scale system design although the author, Hamisch, does not claim that this information is based on successful experience. In this chapter it is irritating to have a mixture of flux units varying from lme2 d-l, through U.S. gal ft-” d-’ to kg min-‘/cartridge. It is also irritating that membrane types are not always fully described as to material or at least manufacturer’s code. In spite of these minor complaints the book is well worth using by those thinking of applying membrane operations in the food or bioprocessing industries, or in medical applications. J. A. HOWELL
Advanced
Biochemical
Engineering
edited by H. R. Bungay and G. Belfort; published by Wiley Interscience, New York, 1987; 300 pp.
In pharmaceutical and agrochemical biotechnology, only two or three of the recentlyformed biotechnology companies will survive
into the 1990’s, and most work will be confined to established drug and chemical companies. This is a prediction put forward in the forthright and penetrating overview of biochemical engineering which forms the opening chapter of “Advanced Biochemical Engineering”. This is, on the whole, an excellent book, stemming from the summer school on biochemical engineering at Rensselaer Polytechnic in New York. While most are academics, two of its ten contributors are from industry. The book emphasises the importance of a thorough understanding of the biosciences as well as the quantitative engineering aspects, a particularly valuable approach in an area as subject to bandwaggoneering as biochemical engineering has been. There are three excellent chapters on applied genetics and molecular enzyme engineering which deal with the subjects concisely, but avoid getting bogged down in the morass of acronyms and esoteric jargon by which accounts of these topics are all too often obfuscated. Recent developments in controllable expression vectors will be of particular interest to biochemical process engineers, but it would have been useful to have a more detailed account of yeast transformations in general, in view of the intense current interest in these organisms. On the engineering side, most attention has been given to separation processes, with excellent accounts of sorption and membrane processes. An overview chapter on product recovery, while very good as far as it goes, in fact concentrates on coagulation and filtration, and other processes which undoubtedly qualify as “advanced” are dealt with only briefly. As the whole book has only 300 pages, it would have been worthwhile making room for a chapter giving detailed coverage of chromatography and partition. The book would also be improved by inclusion of an in-depth treatment of fermentation processes, particularly the recent advances in fermentation control. A chapter on computer modelling of bioreactor performance by a professor of mechanical and aerospace engineering contains the remarkable statement, “Enzymes resemble synthetic chemical catalysts” with no further explanation. The account given of the topic is confusing, as equations are stated with little explanation of the assumptions on which they are