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Biotechnology for Pulp and Paper Processing

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Biotechnology for Pulp and Paper Processing Biotechnology for Pulp and Paper Processing Pratima Bajpai Biotechnology for Pulp and Paper Processing Pratima Bajpai Thapar Research and Development Center Colony Patiala, India [email protected] ISBN 978-1-4614-1408-7 e-ISBN 978-1-4614-1409-4 DOI 10.1007/978-1-4614-1409-4 Springer New York Dordrecht Heidelberg London Library of Congress Control Number: 2011941212 © Springer Science+Business Media, LLC 2012 All rights reserved. This work may not be translated or copied in whole or in part without the written permission of the publisher (Springer Science+Business Media, LLC, 233 Spring Street, New York, NY 10013, USA), except for brief excerpts in connection with reviews or scholarly analysis. Use in connection with any form of information storage and retrieval, electronic adaptation, computer software, or by similar or dissimilar methodology now known or hereafter developed is forbidden. The use in this publication of trade names, trademarks, service marks, and similar terms, even if they are not identifi ed as such, is not to be taken as an expression of opinion as to whether or not they are subject to proprietary rights. Printed on acid-free paper Springer is part of Springer Science+Business Media (www.springer.com) Preface The pulp and paper (P&P) industry is traditionally known to be a large contributor to environmental pollution due to its large consumption of energy and chemicals. Biotechnological methods, however, offer potential opportunities for changing the industry toward more environmentally friendly and effi cient operations compared to the conventional methods. The importance of biotechnology lies in its potential for more specifi c reactions, less environmentally deleterious processes, energy savings, and capacity to be used in place of nonbiological processes. Increased pulp yield, improved fi ber properties, enhanced paper recycling, reduced processing and envi- ronmental problems, and energy effi ciency are all consequences of biotechnological processes in the pulp and paper industry. The number of possible applications of biotechnology in pulp and paper manufacture has grown steadily during the past 3 decades. Many applications have approached or are approaching commercial real- ity. Applications that have been successfully transferred to commercial use include xylanases for bleach boosting; cellulases for improved drainage; lipases for pitch removal; cellulase–hemicellulase mixture for deinking and fi ber modifi cation; esterases for stickies control; and levan hydrolase, proteases, cellulases, amylases, etc. for slime removal. “Biotechnology for Pulp and Paper Processing” gives updated information on various biotechnological processes useful in the pulp and paper industry; these processes could help in reducing environmental pollution problems, in addition to other benefi ts. Various chapters deal with latest developments in the areas like Tree improvement, Raw material preparation, Pulping, Bleaching, Deinking, Fiber modifi cation, Slime control, Stickies control, Production of dis- solving grade pulp, Shive removal, Vessel picking, Degradation of pollutants, Retting of fl ax, Treatment of exhaust gasses for removal of odorous emissions, and Biosolids management. Biotechnology for Pulp and Paper Processing also includes a chapter on Forest Products Biorefi nery. Biorefi neries actually can help pulp mills use by-products and residual products of the papermaking process to create addi- tional high-value revenue streams. The major benefi ts, limitations, and future pros- pects of these processes have also been discussed. Patiala, India Pratima Bajpai v Contents 1 Introduction ............................................................................................ 1 1.1 Introduction ..................................................................................... 1 References ................................................................................................ 4 2 Brief Description of the Pulp and Paper Making Process .................. 7 2.1 Introduction ..................................................................................... 7 2.2 Pulp and Paper Making Process ...................................................... 8 2.2.1 Pulp Making Process ........................................................... 8 2.2.2 Stock Preparation and Paper Making Process..................... 10 References ................................................................................................ 13 3 Tree Improvement .................................................................................. 15 3.1 Introduction ..................................................................................... 15 3.1.1 Forest Trees in the Age of Modern Genetics ...................... 16 References ................................................................................................ 21 4 Biodebarking .......................................................................................... 23 4.1 Introduction ..................................................................................... 23 4.2 Enzymes Used for Debarking ......................................................... 26 4.3 Application of Enzymes for Debarking .......................................... 26 4.4 Advantages of Biodebarking ........................................................... 29 4.5 Limitations and Future Prospects .................................................... 29 References ................................................................................................ 30 5 Biodepitching .......................................................................................... 33 5.1 Introduction ..................................................................................... 33 5.2 Environmental Impact of Lipophilic Extractives ............................ 34 5.3 Methods for Pitch control ............................................................... 36 5.3.1 Conventional Treatment ...................................................... 36 5.3.2 Biological Treatment ........................................................... 36 5.4 Advantages, Limitations, and Future Prospects .............................. 49 References ................................................................................................ 50 vii viii Contents 6 Bioretting ................................................................................................ 57 6.1 Introduction ..................................................................................... 57 6.2 Methods for Retting ........................................................................ 58 6.3 Enzymes Used in Flax-Retting ....................................................... 59 6.4 Application of Enzymes in Flax-Retting ........................................ 59 6.5 Effect of Enzyme-Retting on Fiber Yield and Properties ............... 64 6.6 Effect of Enzyme-Retting on Effl uent Properties ........................... 64 References ................................................................................................ 65 7 Biopulping ............................................................................................... 67 7.1 Introduction ..................................................................................... 67 7.2 Pulping Processes ............................................................................ 68 7.2.1 Mechanical Pulping ............................................................ 68 7.2.2 Semichemical Pulping ........................................................ 69 7.2.3 Chemical Pulping ................................................................ 70 7.3 Biomechanical Pulping ................................................................... 71 7.4 Biochemical Pulping ....................................................................... 79 7.5 Biopulping with Laccase Mediator System .................................... 84 7.6 Mechanism of Biopulping ............................................................... 84 7.7 Advantages of Biopulping .............................................................. 86 7.8 Limitations and Future Prospects .................................................... 87 References ................................................................................................ 87 8 Biobleaching ........................................................................................... 93 8.1 Introduction ..................................................................................... 93 8.2 Xylanase Enzymes .......................................................................... 93 8.2.1 Production and Properties of Xylanases ............................. 94 8.2.2 Performance of Xylanases in Bleaching ............................. 98 8.2.3 Effect of Xylanases on Pulp and Effl uent Quality .............. 104 8.2.4 Mechanism of Bleaching .................................................... 104 8.2.5 Conclusion and Future Prospects ........................................ 105 8.3 Lignin-Oxidizing Enzymes ............................................................. 106 8.3.1 Performance of Lignin-Oxidizing Enzymes in Bleaching ......................................................... 106 8.3.2 Effect of Lignin-Oxidizing Enzymes on Pulp and Effl uent Quality ............................................................ 116 8.3.3 Mechanism of Bleaching .................................................... 117 8.3.4 Advantages, Limitations, and
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