Basu Combustion and Gasification in Fluidized Beds

Erscheinungsjahr 2006
ISBN: 978-1-4200-0515-8
Verlag: Taylor & Francis
Format: PDF
Kopierschutz: Adobe DRM (»Systemvoraussetzungen)

E-Book, Englisch, 496 Seiten

Besides being one of the best Clean Coal Technologies, fluidized beds are also proving to be the most practical option for biomass conversion. Although the technology is well established, the field lacks a comprehensive guide to the design and operating principles of fluidized bed boilers and gasifiers. With more than 30 years of research and industrial experience, Prabir Basu answers this pressing need with Combustion and Gasification in Fluidized Beds. This book is a versatile resource that explains how fluidized bed equipment works and how to use the basic principles of thermodynamics and fluid mechanics in design while providing insight into planning new projects, troubleshooting existing equipment, and appreciating the capabilities and limitations of the process. From hydrodynamics to construction and maintenance, the author covers all of the essential information needed to understand, design, operate, and maintain a complete fluidized bed system. It is a must for clean coal technology as well as for biomass power generation. Beginning with a general introduction to fossil or biofuel conversion choices, the book surveys hydrodynamics, fundamentals of gasification, combustion of solid fuels, pollution aspects including climate change mitigation, heat transfer in fluidized beds, the design and operation of bubbling and circulating fluidized bed boilers, and various supporting components such as distributor grates, feeding systems, and gas-solid separators.

Zielgruppe

Mechanical and chemical engineers in thermal and process industries, energy and environmental engineers, researchers in fluidized beds, technicians and operators involved in operating and maintaining fluidized bed boilers or plants, and undergraduate and graduate students in these fields.

Autoren/Hrsg.

Basu, Prabir

Fachgebiete

• Technische Wissenschaften Verfahrenstechnik | Chemieingenieurwesen | Biotechnologie Verfahrenstechnik, Chemieingenieurwesen

Inhaltsverzeichnis

INTRODUCTION

Background

Fluidized Bed Equipment

Features of Fluidized Beds

Fluidized Bed and Other Clean Coal Options

HYDRODYNAMICS

Regimes of Fluidization

Fast Fluidized Bed

Hydrodynamic Regimes in a CFB

Hydrodynamic Structure of Fast Beds

Gas–Solid Mixing

Scale-Up

FLUIDIZED BED GASIFICATION

Types of Gasifiers

Theory

Effect of Operating Parameters on Gasification

Effect of Feed Properties on Gasification

Fluidized Bed Gasification

Examples of Some Fluidized Bed Gasifiers

Gas Cleaning

Design Methods

Modeling of Fluidized Bed Gasification

Appendix 3A: Estimating Equilibrium Gas Composition

Appendix 3B: An Example of a Fluidized Bed Biomass Gasifier

COMBUSTION

Stages of Combustion

Factors Affecting Combustion Efficiency

Combustion in Bubbling Fluidized Bed Boilers

Combustion in Circulating Fluidized Bed Boilers

Biomass Combustion

EMISSIONS

Air Pollution

Sulfur Dioxide Emission

Nitrogen Oxide Emission

Nitrous Oxide Emission

Mercury Emission

Carbon Monoxide Emission

Carbon Dioxide Emission

Emission of Trace Organics

Particulate Emission

HEAT TRANSFER

Gas-to-Particle Heat Transfer

Heat Transfer in Circulating Fluidized Beds

Heat Transfer in Bubbling Fluidized Bed

Freeboard Heat Transfer in Bubbling Fluidized Beds

Heat Transfer in Commercial-Size CFB Boilers

BUBBLING FLUIDIZED BED BOILER

Description of a BFB Boiler

Features of BFB Boilers

Thermal Design of Bubbling Fluidized Bed Boilers

Combustion in Bubbling Fluidized Bed

Furnace Design

Start-Up Procedure and Control

Some Operational Problems and Remedies

Design of Feed Systems for BFB Bed Boiler

CIRCULATING FLUIDIZED BED BOILER

General Arrangement

Types of CFB Boilers

Non-CFB Solid Circulation Boilers

Combustion in a Circulating Fluidized Bed Furnace

Design of CFB Boilers

Furnace Design

Design of Heating Surfaces

Auxiliary Power Consumption

Control of CFB Boilers

Supercritical CFB Boiler

MATERIAL ISSUES

Material Selection Criteria

Erosion Potential

Corrosion Potentials

Steels Used in Fluidized Bed Boilers

Refractory and Insulations

Expansion Joints

SOLID HANDLING SYSTEMS FOR FLUIDIZED BEDS

Solid Handling Systems

Biomass Handling Systems

Feed System for Bubbling Beds

Feed System for Circulating Fluidized Beds

Design of Pneumatic Transport Lines for Solids

AIR DISTRIBUTION GRATE

Distributor Plates

Operation of Distributors

Design Methods

Practical Considerations

GAS–SOLID SEPARATORS

Cyclones

Impact Separator

Inertial Separators

SOLID RECYCLE SYSTEMS

Types of Non-mechanical Valves

Principles of Operation

Design of Loop-Seal

Design of L-Valve

Practical Considerations

Nomenclature

References

APPENDIX 1: CHARACTERISTICS OF SOLID PARTICLES

APPENDIX 2: STOICHIOMETRIC CALCULATIONS

APPENDIX 3: SIMPLIFIED MODEL FOR SULFUR CAPTURE

APPENDIX 4: TABLES OF DESIGN DATA