Mechanical Engineering Series

Frederick F. Ling Series Editor

Springer Science+Business Media, LLC

Mechanical Engineering Series

Introductory Attitude Dynamics F.P. Rimrott

Balancing of High-Speed Machinery M.S.Darlow

Theory of Wire Rope, 2nd ed. G.A. Costello

Theory of Vibration: An Introduction, 2nd ed. A.A. Shabana

Theory of Vibration: Discrete and Continuous Systems, 2nd ed. AA Shabana

Laser Machining: Theory and Practice G. Chryssolouris

Underconstrained Structural Systems E.N. Kuznetsov

Principles of Heat Transfer in Porous Media, 2nd ed. M. Kaviany

Mechatronics: Electromechanics and Contromechanics D.K.Miu

Structural Analysis of Printed Circuit Boam Systems P.A Engel

Kinematic and Dynamic Simulation of Multibody Systems: The Real-Time Challenge J. Garda de Jal6n and E. Bayo

High Sensitivity Moire: Experimental Analysis for Mechanics and Materials D. Post, B. Han, aod P. Ifju

Principles of Convective Heat Transfer M. Kaviaoy

(continued after index)

Prabir Basu Cen Kefa Louis Jestin

Boilers and Burners Design and Theory

With 250 Figures

Springer

Prabir Basu Cen Kefa Department of Mechanical Engineering Technical University of Nova Scotia P.O. Box 1000

Institute of Thermal Engineering Zhejiang University Zheda Road

Halifax, Nova Scotia B3J 2X4, Canada Hangzhou, Zhejiang 310027, China

Louis Jestin Department Equipment Electricite de France 12-14 Avenue Dutrievoz F-69628 Villeurbanne, France

Series Editor Frederick F. Ling Emest F. Gloyna Regents Chair in Engineering Department of Mechanical Engineering The University of Texas at Austin Austin, TX 78712-1063, USA

and William Howard Hart Professor Emeritus Department of Mechanical Engineering,

Aeronautical Engineering and Mechanics Rensselaer Polytechnic Institute Troy, NY 12180-3590, USA

Library of Congress CataIoging-in-Publication Data Basu, Prabir, 1946-

Boilers and bumers : design and theory / Prabir Basu, Cen Kefa. Louis Jestin.

p. em. - (MeehanicaI engineering series) Includes bibliographical references. ISBN 978-1-4612-7061-4 ISBN 978-1-4612-1250-8 (eBook) DOI 10.1007/978-1-4612-1250-8 1. Steam-boilers-Design and construction. 2. Oil bumers-Design

and construction. 1. Cen, Kefa. II. Jestin, Louis. III. Title. IV. Series : Mechanical engineering series (Berlin, Germany) TJ290.B37 1999 62 1.1'8-<1c2 I 99-17360

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© 2000 Springer Seienee+Business Media New York Originally published by Springer-Verlag New York, Ine. in 2000 Softeover reprint ofthe hardeover Ist edition 2000

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ISBN 978-1-4612-7061-4 SPIN 10707311

Series Preface

Mechanical engineering, an engineering discipline borne of the needs of the in­dustrial revolution, is once again asked to do its substantial share in the call for industrial renewal. The general call is urgent as we face profound issues of produc­tivity and competitiveness that require engineering solutions, among others. The Mechanical Engineering Series features graduate texts and research monographs intended to address the need for information in contemporary areas of mechanical engineering.

The series is conceived as a comprehensive one that covers a broad range of con­centrations important to mechanical engineering graduate education and research. We are fortunate to have a distinguished roster of consulting editors on the advi­sory board, each an expert in one of the areas of concentration. The names of the consulting editors are listed on the facing page of this volume. The areas of concen­tration are: applied mechanics; biomechanics; computational mechanics; dynamic systems and control; energetics; mechanics of materials; processing; production systems; thermal science; and tribology.

I am pleased to present this volume in the series: Boilers and Burners: Design and Theory, by Prabir Basu, Cen Kefa, and Louis Jestin. The selection of this volume underscores again the interest of the Mechanical Engineering Series to provide our readers with topical monographs as well as graduate texts in a wide variety of fields.

Austin, Texas Frederick F. Ling

Mechanical Engineering Series

Frederick F. Ling Series Editor

Advisory Board

Applied Mechanics

Biomechanics

Computational Mechanics

Dynamical Systems and Control

Energetics

Mechanics of Materials

Processing

Production Systems

Thermal Science

Trihology

F.A. Leckie University of California, Santa Barbara

V.C.Mow Columbia University

H.T. Yang University of California, Santa Barbara

K.M. Marshek University of Texas, Austin

1.R. Welty University of Oregon, Eugene

I. Finnie University of California, Berkeley

K.K. Wang Cornell University

G.-A. Klutke Texas A&M University

A.E. Bergles Rensselaer Polytechnic Institute

W.O. Winer Georgia Institute of Technology

Preface

Modern society owes a great deal to fossil fuels, which have accelerated man's progress from the cave to the present age of jets and computers. Utilization of this precious gift of nature is central and critical to our lives. This book is about rational utilization of fossil fuels for generation of heat or power. The book is intended for undergraduate and graduate students with an interest in steam power plants, burners, or furnaces. For researchers, it is a resource for applications of theory to practice. Plant operators will find solutions to and explanations of many of their daily operational problems. Designers will find this book filled with required data, design methods, and equations. Finally, consultants will find it useful for design evaluation.

This book uses a format of theory-based practice. Each chapter begins with an ex­planation of a process. Then it develops equations from first principles and presents experiment-based empirical equations. This is followed by design methodology, which in many cases is explained by worked-out examples. Thus, the book retains the interest of the reader and help remove doubts if any on the theory.

The present monograph is a joint effort of writers on three continents-Asia, Europe, and North America-and a marriage of two scientific traditions-Eastern and Western. In the West, boilers and burners are designed for high levels of performance, but their design methods and data are buried under commercial secrecy. Very few books or even research papers are available giving exact design standards. Thus, there is limited opportunity for infonnation exchange on design data and methodologies. The energy industry in the Eastern European countries and China, on the other hand, did not have much commercial impetus for burying their design standards under secrecy. So their design methods and data were freely exchanged, and debated in the scientific community. Eventually, they fonned into national standards. These elaborate thermal design standards were developed on the basis of experience in the design and operations of thousands of boilers and burners. However, the difference in language and scientific conventions prevented easy access of Western readers to this wealth of information available in China and Eastern European countries. The present book synthesizes design methods and data from both sides of the scientific world and presents the same in a simple Western format.

viii Preface

The book greatly benefitted from diverse professional backgrounds of three authors. Professor Cen Kefa, Head of the Institute of Thermal Power Engineering of Zhejiang University, is holder of the coveted distinction of Academician for his lifelong contribution to the Chinese boiler industry. He received his early education in boilers and power plants in the former Soviet Union. Thereafter, he worked closely with Chinese boiler and burncr industry manufacturers perfecting their design standards. The research and development work he and his colleagues have carried out in the past four decades on boilers and burners greatly contributed to this book.

Dr. Louis Jestin, Head of the Heat Exchanger Section ofthc Fossil Fuel Division of the Electricite de France, is a specialist in heat transfer. He is involved in the design rcvicw of all new circulating fluidized bed boilers commissioned by this company. His team also carried out in-depth technical analyses of several supercritical boiler projects. His intimate contact with modern fossil fuel boilers and familiarity with European designs greatly enriched this book.

Dr. Prabir Basu, Profcssor in Mcchanical Engineering in Dalhousie University and President of Greenfield Research Inc., is a specialist in fluidizcd bed boilers. He carried out extensive design and development work in government research laboratory, boilcr manufacturing company, and universities. He participated in the development of the Indian boiler standard. His research and design experience in fluidized bed boilers contributed much to this book.

We thank Mr. 5.5. Kelkar, Ex-Vice President, Deutsche Babcock Power System Ltd., India, who used his 30 years experience of boiler dcsign and familiarity with German, British, Indian, and U.S. boiler codes to write Chapter 17 on pressure part design.

Our special thanks go to Prof. Jianrcn Fan, Prof. Qiang Yao, and Dr. Zuohe Chi for their significant contributions to a number of chapters in this book. Their tireless effort in data collection, draft preparation, and figure drafting provided critical support to this projcct. Dr. Jayson Grcenblatt and Prof. David Mackay proofread many versions of the manuscript. Dr. Leming Cheng, Mrs. Sanja Boskovic, and Mr. Animesh Dutta greatly helped with preparation of the final manuscript.

Finally the authors thank their waves for their support to this project.

Prabir Basu Halifax, Nova Scotia, Canada Cen Kefa Hangzhou, Zhejiang, China Louis Jestin Lyon, France

Contents

Series Preface Preface

1 Introduction 1-1 Principles of Boiler Operation 1-2 Classification of Boilers . 1-3 Description of Boilers

References . . . . . . . .

2 General Design Considerations 2-1 Boiler Specifications. 2-2 Design Steps

References . . . . . .

3 Fuel and Combustion Calculations 3-1 Features of Fuel . . . . . . . . 3-2 Stoichiometric Calculations .............. . 3-3 Enthalpy Calculation of Air and Combustion Products 3-4 Heat Balance . . . . . . . . . 3-5 Generation of S02 and NOx •

Nomenclature References . . . . . . . . . .

4 Coal Preparation Systems for Boilers 4-1 Coal Preparation Systems . . . 4-2 Pulverizing Properties of Coal 4-3 Pulverizing Air System ... . 4-4 Size-Reducing Machines .. . 4-5 Other Components for Coal Preparation Systems 4-6 Design of Coal Preparation System

for Pulverized Coal Boilers ........... .

v vii

1 1 6 6

14

15 15 17 20

21 21 28 36 37 46 48 51

52 52 56 59 63 70

73

x Contents

4-7 Fuel Feeding in Fluidized Bed Boilers 76 Nomenclature 78 References . . . . 79

5 Design of Oil Burners 80 5-1 Design of Oil Supply System 80 5-2 Oil Atomizers .. . . . . . . 82 5-3 Air Registers . . . . . . . . . 108 5-4 Design Principles of Oil Fired Boilers 118

Nomenclature 125 References . . . . . . . . . . 127

6 Boiler Furnace Design Methods 128 6-1 General Design Principles. . . . . . . . . . . . . . . . 128 6-2 Flame Emissivity .................... 135 6-3 Heat Transfer Calculations for the PC Boiler Furnace. 140 6-4 Water Wall Arrangement . . . . . . . . . . . . . . . . 146 6-5 Fouling and Thermal Efficiency Factors

for Water Wall Tubes ....... 147 6-6 Temperature Field Coefficient, M .. 149 6-7 Furnace Emissivity .......... 150 6-8 Distribution of Heat Load in Furnace. 151

Nomenclature 157 References . . . . . . . . 159

7 Convective Heating Surfaces 161 7 -1 Design of Superheater and Reheater . . . . . . . . . . . . . . 161 7-2 Temperature Control in Superheater and Reheater. . . . . . . 167 7-3 Adjustment of Heat Absorption in Superheater and Reheater . 172 7 -4 Economizer .................. 178 7 -5 Air Heater . . . . . . . . . . . . . . . . . . . . . . . . . . . 180 7-6 Arrangement of Back-Pass Heating Surfaces ........ 185 7-7 Heat Transfer Calculations for Convective Heating Surfaces 187 7-8 Design Methods of Convection Heating Surfaces 206

Nomenclature 207 References 211

8 Swirl Burners 212 8-1 Design of a Swirl Burner 212 8-2 Flow Resistance in Swirl Burners. 225 8-3 Examples of Swirl Burners . . . . 226 8-4 Arrangement of Multiple Swirl Burners 230 8-5 Design Procedure of Swirl Burners. 233

Nomenclature 239 References . . . . . . . . . . . . . . 241

9 Design of Novel Burners 9-1 Types of PC Burners. . . . . . . 9-2 PC Burner With Blunt Body .. 9-3 Precombustion Chamber Burner 9-4 Boat Burner . . . . . . . . . . . 9-5 Co-Flow Jet Burner With High Differential Velocity 9-6 Counter-Flow Jet Burner ......... . 9-7 Dense and Lean Phase PC Burner .... . 9-8 Down-Shot Flame Combustion Technique . 9-9 Low NOx Burner.

Nomenclature References . . . .

10 Tangentially Fired Burners 10-1 General Descriptions . . . . . . . . . . 10-2 Design of Burners With Peripheral Air 10-3 Design of Tilting Burners ....... . 10-4 Burners for Bituminous Coal ..... . 10-5 Anthracite and Lean Coal Fired PC Burner 10-6 Brown Coal Fired Direct Burner ..... . 10-7 Multifuel Burner ............. . 10-8 Design Methods for Tangentially Fired Boilers 10-9 Example of Burner Design

Nomenclature References . . .

11 Fluidized Bed Boilers 11-1 Fluidized Bed Boiler .......... . 11-2 Major Features of Fluidized Bed Boilers 11-3 Basics of Fluidized Beds ..... 11-4 Bubbling Fluidized Bed Boilers . 11-5 Circulating Fluidized Bed Boilers 11-6 Distributor Plates . . 11-7 Loop Seals . . . . . . 11-8 Gas-Solid Separators

Nomenclature References . . . . . .

12 Steam-Water Circulation in Boiler 12-1 Natural Circulation System ............. . 12-2 Calculations for Simple and Complex Tube Circuits 12-3 Two-Phase Flow Resistance ....... . 12-4 Height of Economizer Section in the Riser 12-5 Worked-Out Example.

Nomenclature References . . . . . . .

Contents xi

242 242 243 246 248 249 250 253 257 259 266 267

269 269 279 281 284 286 291 293 294 297 300 301

302 302 304 309 314 319 327 331 334 340 344

347 346 359 360 362 364 369 371

xii Contents

13 Forced Circulation for Supercritical or Subcritical Boilers 13-1 General Description . . . . . . . . . . . . . . . 13-2 Design Principle of Forced Circulation Boiler 13-3 Features of Forced Circulation Boilers. 13-4 Supercritical Boilers ............. .

14 Corrosion and Fouling of Heat Transfer Surfaces 14-1 High-Temperature Corrosion of External Surfaces 14-2 Prevention of High-Temperature Corrosion .... 14-3 Low-Temperature Corrosion on External Surfaces 14-4 Corrosion and Scaling of Internal Surfaces 14-5 Fouling and Siagging .......... . 14-6 Calculation of Soot and Ash Deposition . . 14-7 Prediction of Siagging Potential . . . . . . 14-8 Design Measure for Reduction of Fouling and Slagging

Nomenclature References . . . . . . . .

15 Erosion Prevention in Boilers 15-1 Theory of Erosion of Heating Surfaces 15-2 Worked-Out Example ......... . 15-3 Factors Influencing Tube Erosion .. . 15-4 Analyses of Erosion of Tube Banks in Cross-Flow 15-5 Permissible Gas Velocity for Safe Operation 15-6 Erosion Protection for the Economizer,

Reheater, and Superheater .... 15-7 Erosion in Tubular Air Heaters .. 15-8 Erosion in Fluidized Bed Boilers.

Nomenclature References . . . . . . . . . . . .

16 Pressure Drop in Gas and Air Ducts 16-1 Draft Systems ................ . 16-2 Pressure Drop in Air and Gas Duct Systems 16-3 Pressure Drop Across Heating Surfaces . 16-4 Pressure Drop in Natural Draft Gas Path 16-5 Pressure Drop Through Air Ducts ... . 16-6 Selection of Fans ............ . 16-7 Pressure Drop Through Water or Steam Tubes

Nomenclature References . . . . . . . . . . . .

17 Mechanical Design of Pressure Parts 17 -1 Selection of Materials . . . . . . 17 -2 Important Mechanical Properties of Various Materials

372 373 374 375 381

385 386 392 397 402 406 412 416 421 423 424

426 426 431 433 436 439

444 448 450 454 456

457 457 459 466 471 475 479 480 481 483

485 485 487

Contents xiii

17-3 Fundamental Metallurgical Concepts to Improve Steel Properties .... .

17-4 Design Methods .......... . 17-5 Thickness (Scantling) Calculations.

Nomenclature References . .

18 Tables of Design Data Table 18-1 Specific heat of air, flue gas and

ash at atmospheric pressure. . . Table 18-2 Some physical properties of iron,

metal, and selected steels . . . . . Table 18-3 Linear thermal expansion of steel Table 18-4 Specific heat capacity of steel Table 18-5 Electrical resistivity of steel ... Table 18-6 Thermal conductivity of steel .. Table 18-7 Density, heat capacity, and heat conductivity

for metals .................. . Table 18-8 Thermal properties of the saturated water and steam

490 495 509 523 523

524

525

526 526 527 527 527

528

(arranged by temperature) .............. 530 Table 18-9 Thermal properties of the saturated water and steam

(arranged by pressure) ............ 532 Table 18-10 Thermal properties of unsaturated water and

superheated steam at different pressures. 534 Table 18-11 Conversion factors ... . . . . . . . . . . . 541

Index 553