Technologies for Converting Biomass to Useful Energy Combustion, gasification, pyrolysis, torrefaction and fermentation

Editor: Erik Dahlquist School of Sustainable Development of Society and Technology, Malardalen University, Hogskoleplan Vasteras, Sweden

CRC Press Taylor & Francis Group Boca Raton

London

New York

CRC Press is an imprint of the Taylor & Francis Croup, an informa business

A BALKEMA BOOK

Leiden

Table of contents

About the book series

vii

Editorial board

ix

Contributors

xxxiii

Foreword by Yang Yong-Ping

xxxv

J

Editor's Foreword

xxxvii

About the editor

' xxxix

Acknowledgements

xli

1.

An overview of thermal biomass conversion technologies Erik Dahlquist

2.

Simulations of combustion and emissions characteristics of biomass-derived fuels Suresh K. Aggarwal 2.1 Introduction 2.2 Thermochemical conversion processes 2.2.1 Direct biomass combustion 2.2.2 Biomass pyrolysis 2.2.3 Biomass gasification 2.3 Syngas and biogas combustion and emissions 2.3.1 Syngas combustion and emissions 2.3.2 Non-premixed and partially premixed syngas flames 2.3.3 High pressure and turbulent syngas flames 2.3.4 Syngas combustion in practical devices 2.4 Biogas combustion and emissions _ 2.5 Concluding remarks

3.

Energy conversion through combustion of biomass including animal waste Kalyan Annamalai, Siva Sankar Thanapal, Ben Lawrence, Wei Chen, Aubrey Spear & John Sweeten 3.1 Introduction 3.2 Overview on energy conversion from animal wastes 3.2.1. Manure source 3.3 Biological conversion 3.3.1 Digestion 3.3.2 Fermentation 3.4 Thermal energy conversion 3.5 Fuel properties 3.5.1 Proximate and ultimate analyses 3.5.2 Empirical formula for heat values 3.5.2.1 The higher heating value per unit mass of fuel 3.5.2.2 The higher heat value per unit stoichiometric oxygen 3.5.2.3 Heat value of volatile matter 3.5.2.4 Volatile matter and stoichiometry

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5 5 6 6 7 10 11 11 19 23 25 26 28 35

35 36 36 39 39 39 40 42 42 43 43 47 51 51

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3.6 3.7

3.8

3.9 3.10

3.11

3.12 3.13 3.14

3.15 4.

3.5.2.5 Stoichiometric A:F 51 3.5.2.6 Flue gas volume 51 3.5.3 Fuel change and effect on CO2 52 3.5.4 Air flow rate and multi-fuels firing •> 53 3.5.5 CO2 and fuel substitution 53 TGA studies on pyrolysis and ignition 53 3.6.1 Pyrolysis 54 Model 54 3.7.1 Single reaction model: Conventional Arrhenius method 55 3.7.2 Parallel Reaction Model (PRM) 56 Chemical kinetics 58 3.8.1 Activation energy from single reaction model 58 3.8.2 Activation energies from parallel reaction model 59 Ignition 59 3.9.1 Ignition temperature 59 Cofiring .61 3.10.1 Experimental set up and procedure 62 3.10.2 Experimental parameters 65 3.10.3 02 and equivalence ratio 65 3.10.4 CO and CO2 emissions .65 3.10.5 Burnt fraction 69 3.10.6 NOj emissions 69 3.10.7 Fuel nitrogen conversion efficiency 72 Cofiring FB with coal 75 3.11.1 NO emissions with longer reactor 75 3.11.2 Effect of blend ratio 76 Reburn 76 Low NOj Burners (LNB) 80 Gasification 80 3.14.1 Experimental setup 81 3.14.2 Experimentation 82 3.14.3 Experimental procedure 83 3.14.4 Results and discussion 83 3.14.4.1 Fuel properties 83 3.14.4.2 Experimental results and discussion 83 3.14.4.2.1 Temperature profiles for air gasification 84 3.14.4.2.2 Temperature profiles for enriched air gasification and CO2: O2 gasification 85 3.14.4.2.3 Gas composition results with air 86 3.14.4.2.4 Gas composition results with enriched air and ' CO2: O2 mixture 88 3.14.4.2.5 HHV of gases and energy conversion efficiency 89 Summary and conclusions 91

Co-combustion coal and bioenergy and biomass gasification: Chinese experiences Changqing Dong & Xiaoying Hu 4.1 Biomass resources in China 4.1.1 Agricultural residues 4.1.2 Livestock manure 4.1.3 Municipal and industrial waste 4.1.4 Wood processing remainders 4.2 Co-combustion in China 4.2.1 Introduction

97 97 97 98 99 99 99 99

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4.2.2 4.2.3 4.2.4

Methods and technologies . Advantages and disadvantages Research status 4.2.4.1 Different biomass for co-combustion 4.2.4.2 Biomass gasification gas for co-combustion 4.2.4.3 Pollutant emissions from co-combustion 4.2.4.3.1 The influence of solid biomass fuel. 4-2.4.3.2 The. influence of biomass gasification gas 4.2.5 The applications of co-combustion in China 4.2.5.1 Chuang Municipality Lutang Sugar Factory 4.2.5.2 Fengxian XinYuan Biomass CHP Thermo Power Co., Ltd 4.2.5.3 Heilongjiang Jiansanjiang Heating and Power Plant 4.2.5.4 Baoying Xiexin Biomass Power Co., Ltd 4.2.6 Shiliquan power plant 4.3 Biomass gasification in China 4.3.1 Introduction 4.3.2 Gasification technology development 4.3.3 Biomass gasification gas as boiler fuel • 4.3.3.1 The feasibility of biomass gasification gas as fuel 4.3.3.2 The superiority of biomass gasification gas as fuel 4.3.4 Biomass gasification gas used for drying 4.3.5 Biomass gasification power generation . 4.3.6 Biomass gasification for gas supply ' 4.3.7 Hydrogen production from biomass gasification 4.3.8 Biomass gasification polygeneration scheme 4.3.9 Policy-oriented biomass gasification in China ; 4.3.9.1 Guide public awareness 4.3.9.2 Government investment in R&D of key technologies 4.3.9.3 Fiscal incentives and market regulation measures 4.4 Conclusions 4.4.1 Co-combustion 4.4.2 Gasification 5.

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Biomass combustion and chemical looping for carbon capture and storage Umberto Desideri & Francesco Fantozzi 5.1 Feedstock properties 5.1.1 Biomass and biofuels definition and classification 5.1.2 Biomass composition and analysis 5.1.3 Biomass analysis 5.1.3.1 Moisture content (EN 14774-2, 2009) 5.1.3.2 Ash content (EN 14775, 2009) 5.1.3.3 Volatile matter (EN 15148,2009) 5.1.3.4 Heating value (EN 14918,2009) 5.1.3.5 Carbon, hydrogen and nitrogen content (EN 15104, 2011) 5.1.3.6 Density (EN 15103,2010) 5.1.3.7 Sulfur content analysis (EN 15289, 2011) 5.1.3.8 Chlorine and fluorine content analysis (EN 15289, 2011) 5.1.3.9 Chemical analysis (EN 15297, 2011 and EN 15290, 2011) 5.1.3.10 Size (CEN/TS 15149-1:2006, CEN/TS 15149-2:2006, CEN/TS. 15149-3:2006) 5.2 Combustion basics. 5.2.1 Introduction 5.2.2 Heating and drying

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100 101 102 102 106 109 110 110 112 112 113 114 114 115 116 116 116 116 116 117 118 118 120 121 • 122 123 124 124 124 124 124 125 129 129 129 131 132 133 133 133 134 135 136 136 136 136 136 137 137 139

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5.3

5.4

6.

5.2.3 Pyrolysis and devolatilization 5.2.4 Char oxidation (glowing or smoldering combustion) 5.2.5 Volatiles oxidation (flaming combustion) 5.2.6 Combustion rates, flame temperature and efficiency Combustors 5.3.1 Introduction to biomass combustion systems 5.3.2 Fixed bed combustion 5.3.2.1 Pileburners 5.3.2.2 Grate burners 5.3.3 Moving bed combustors 5.3.3.1 Suspension burners 5.3.3.2 Fluidized bed combustors 5.3.4 Design and operation issues 5.3.4.1 Design principles 5.3.4.2 Deposit and slagging problems Chemical looping combustion 5.4.1 Chemical looping processes 5.4.2 Chemical looping reactions

Biomass and black liquor gasification Klas Engvall, Truls Liliedahl & Erik Dahlquist 6.1 Introduction 6.2 Theory of gasification 6.3 Operating conditions of importance for the product composition 6.3.1 Fuel types and properties 6.3.1.1 Biomass 6.3.1.2 Black liquor 6.3.1.3 Biomass properties of importance for gasification 6.3.2 Gasifying agent 6.3.3 Temperature 6.4 Gasification systems 6.4.1 Gasification technologies 6:4.1.1 Fixed bed ~ 6.4.1.1.1 Updraft gasifiers 6.4.1.1.2 Downdraft gasifers 6.4.1.1.3 Cross-draft gasifers 6.4.1.2 Fluidized bed gasifiers 6.4.1.2.1 BFB and CFB reactors 6.4.1.2.2 Dual fluidized bed reactors 6.4.1.3 Entrained flow gasifier 6.4.2 Gas cleaning and upgrading 6.4.2.1 Tar and tar removal 6.4.2.2 Thermal and catalytic tar decomposition 6.4.2.2.1 Thermal processes for tar destruction 6.4.2.2.2 Catalytic processes for tar destruction 6.4.2.2.3 Dolomite catalysts 6.4.2.2.4 Nickel catalysts 6.4.2.2.5 Alkali metal catalysts 6.4.2.3 Removal of other impurities found in the product gas 6.4.2.3.1 Alkali metal compounds 6.4.2.3.2 Fuel-bound nitrogen 6.4.2.3.3 Sulfur 6.4.2.3.4 Chlorine

140 141 143 144 148 148 150 150 152 157 157 158 159 159

162 164 165 167

175 175 176 178 178 178 178 179 180 181 181 182 182 182 183 183 184 184 185 186 188 189 191 191 191 192 193 193 193 193 194 194 194

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6.5

6.6

6.7

7.

Gasification applications 6.5.1 Biomass gasification 6.5.1.1 BFB gasifier at Skive 6.5.1.2 Cortus WoodRoll gasification technology 6.5.1.2.1 Gussing plant 6.5.2 Black liquor gasification 6.5.2.1 BL gasification using fluidized bed technology 6.5.2.2 BL gasification using entrained flow technology Modelling of gasification systems 6.6.1 Material arid energy balance models 6.6.1.1 An empirical model for fluidized bed gasification 6.6.2 Kinetic models 6.6.3 Equilibrium models 6.6.3.1 Simulations using an equilibrium model compared to experimental data Outlook 6.7.1 Biomass gasification 6.7.2 Black liquor gasification

Biomass conversion through torrefaction Anders Nordin, Linda Pommer, Martin Nordwaeger & Ingemar Olofsson 7.1 Introduction 7.2 Torrefaction history 7.2.1 Origin of torrefaction processes 7.2.2 Modern torrefaction work (1980-) 7.3 Torrefaction process • • 7.3.1 Energy and mass balances 7.3.2 Solid product characteristics 7.3.2.1 Elemental compositional changes 7.3.2.2 Heating value and volatile content 7.3.2.3 Friability, grinding energy and powder characteristics 7.3.2.4 Feeding characteristics 7.3.2.5 Hydrophobic properties and fungal durability 7.3.2.6 Molecular composition and changes 7.3.3 Gases produced 7.3.3.1 Permanent gases ,7.3.3.2 Condensable gases 7.4 Subsequent refinement processes 7.4.1 Washing 7.4.2 Densification 7.4.2.1 Pelleting 7.4.2.2 Briquetting 7.5 Torrefaction technologies 7.5.1 General 7.5.2 Technologies under development or demonstration 7.5;3 Status of the present production plants erected 7.6 End-use experience 7.7 System analyses and process integration 7.7.1 Importance of total supply chain analysis 7.7.2 Process and system integration 7.8 Economic aspects of torrefaction systems 7.8.1 Investment and operating costs 7.8.2 Costs versus total supply chain savings 7.9 Outlook

xxv

195 195 195 196 197 199 199 201 , 203 203 205 206 208 210 212 213 213

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217 218 218 219 219 221 221 222 223 223 224 225 226 229 229 229 230 230 231 231 232 232 232 233 233 234 235 235 235 236 237 239 240

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Table of contents

Biomass pyrolysis for energy and fuels production Efthymios Kantarelis, Weihong Yang & Wlodzimierz Blasiak 8.1 Introduction 8.2 Technologies 8.2.1 Biomass reception and storage 8.2.2 Fast pyrolysis reactors 8.2.2.1 Bubbling fluidized beds , . 8.2.2.2 Circulating fluidized bed reactors 8.2.2.3 Rotating cone reactors 8.2.3 Char separation 8.2.4 Liquid recovery . 8.3 Products and applications 83.1 Char 8.3.2 Bio-oil 8.3.2.1 Composition and properties 8.3.2.1.1 Homogeneity, 8.3.2.1.2 Water content 8.3.2.1.3 Viscosity/rheological properties 8.3.2.1.4 Acidity 8.3.2.1.5 Heating value 8.3.2.1.6 Stability 8.3.2.1.7 Health and safety 8.3.2.1.8 Other important properties 8.3.2.2 Bio-oil applications 8.3.2.2.1 Heat and power 8.3.2.2.2 Gasoline and diesel fuels 8.4 Modeling 8.4.1 One step models 8.4.2 Models with competing parallel reactions 8.4.2.1 Models with secondary reactions 8.5 Recent trends and developments 8.6 Conclusions Solid-state ethanol production from biomass Shi-Zhong Li 9.1 Introduction 9.1.1 The history of SSF. 9.2 The principle of SSF 9.2.1 Microorganisms in SSF.... 9.2.2 The substrate in SSF 9.2.2.1 The source of the substrate 9.2.2.2' The character of the substrate 9.2.2.3 The water content of the substrate 9.2.2.4 The solid-phase properties of substance 9.3 The process of SSF 9.3.1 The characteristics of SSF 9.3.1.1 Cell growth and measurement of products 9.3.1.2 Sterile control 9.3.2 The effective factors of SSF 9.3.2.1 Carbon and nitrogen sources 9.3.2.2 Temperature and heat transfer 9.3.2.3 Moisture and water activity

245 245 247 248 248 248 249 251 252 252 253 253 253 253 254 255 255 256 256 256 257 257 257 258 260 265 265 265 266 269 271 279 279 279 280 280 280 280 280 280 281 281 281 281 281 281 282 282 283

Table of contents

9.4 9.5

10.

9.3.2.4 Ventilation and mass transfer 9.3.2.5 pH value 9.3.3 SSF reactors 9.3.3.1 Static SSF reactor • 9.3.3.2 Dynamic SSF reactor 9.3.3.3 Rotary drum SSF reactor and modeling progress Progress of SSF research Application of SSF in biomass energy fields . 9.5.1 - Sweet sorghum stalk liquid fermentation technology 9.5.2 Sweet sorghum stalk SSF technology 9.5.3 The prospect of SSF 9.5.3.1 Basic theory for research 9.5.3.2 SSF reactor design and scale-up 9.5.3.3 The SSF process and product contamination control

Optimization of biogas processes: European experiences Anna Behrendt, S. Drescher-Hartung & Thorsten Ahrens 10.1 Introduction 10.2 Substrates for biogas processes and specialities 10.2.1 Available substrate streams for biogas processes, composition and organic amounts 10.2.1.1 Water and organic matter concentration 10.2.1.2 Requirements for pretreatment including sorting and sanitation 10.2.2 Biogas potentials and energy output . 10.2.2.1 Identification of biogas potentials - 10.2.2.2 Biogas potential results and energy output 10.2.2.3 Comparison of energy outputs through biogas and combustion of material 10.2.3 Conclusion: Can energy from waste compete with energy from renewable products? 10.3 Current biogas technologies and challenges • 10.3.1 Biogas fermenter technology 10.3.1.1 Dry digestion application-Examples of biogas plants in Germany 10.3.1.1.1 Plug flow fermenter 10.3.1.1.2 Tower fermenter • 10.3.1.1.3 Garage fermenter 1013.1.2 Wet digestion applications 10.3.1.2.1 System example 10.3.1.2.2 Use of residual waste 10.3.1.3 Laboratory scale technology 10.3.1.3.1 Plug flow fermenter 10.3.1.3.2 Garage fermenter 10.3.2 Regional implementation of fermenter technology 10.3.2.1 One European example: Conditions in Estonia (Kiili Vald) 10.3.2.2 The waste management situation in Kiili Vald 10.3.2.3 The waste management situation in Germany 10.4 Future prospects and individual regional energy solutions 10.4.1 Central and local biogas plants 10.4.1.1 Individual farm plant 10.4.1.2 Biogas parks

xxvii

283 283 283 284 284 284 285 286 287 288 288 288 288 289 293 293 293 293 294 294 296 296 297 300

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301 301 301 302 303 303 303 304 305 305 305 306 306 306 307 308 309 310 310 310 310

xxviii Table of contents

10.5 11.

12.

13.

:

10.4.2 Biogas use Questions for discussions

Biogas - sustainable energy solutions in Nigeria Adeola Ijeoma Eleri 11.1 Introduction 11.2 Review of Nigeria's current energy situation 11.3 Biogas technology in Nigeria 11.3.1 Technical characteristics of biogas digester 11.3.2 Mechanisms of methanogenesis 11.4 Potentials of biogas technology for sustainable development 11.5 Barriers to biogas technology .11.6 Recommendations for scaling up biogas technology in Nigeria 11.7 Conclusions The influence of biodegradability on the anaerobic conversion of biomass into bioenergy RodrigoA. Labatut 12.1 Introduction 12.2 Theoretical aspects and assessment of substrate biodegradability 12.3 Factors limiting substrate biodegradability 12.3.1 Bioenergetics: Cell synthesis vs. metabolic energy 12.3.2 Polymer complexity 12.3.2.1 Carbohydrates 12.3.2.2 Proteins 12.3.2.3 Lipids 12.3.3 Inhibition of biochemical reactions 12.4 Biodegradability of complex, particulate influents: Co-digestion studies 12.4.1 The effect of substrate composition on fD and Ba: BMP studies 12.4.2 Implications of influent biodegradability on anaerobic digestion systems 12.5 Conclusions Pellet and briquette production Torbjorn A. Lestander 13.1 Introduction 13.2 Standardization of solid biofuels 13.3 Feedstock for densification 13.3.1 Raw materials 13.3.2 Biomass has orthotropic mechanical properties 13.4 Pretreatment before densification 13.4.1 Grinding 13.4.2 Pre-heating (e.g. steam addition) 13.4.3 Steam explosion 13.4.4 Ammonia fiber expansion 13.4.5 Drying 13.4.6 Torrefaction 13.5 Densification techniques 13.6 Mechanisms of bonding 13.7 Health and safety aspects when handling pellets and briquettes 13.8 Conclusion 13.9 Questions for discussion

310 311 315 315 316 316 318 319 319 319 321 321

325 325 326 329 . 329 331 331 333 334 336 337 337 338 340 345 345 345 347 347 348 348 349 349 349 349 349 350 351 352 353 353 353

Table of contents xxix

14.

15.

Dynamic modeling and simulation of power plants with biomass as a fuel Yrjd Majanne 14.1 Introduction \ 14.1.1 Use of biomass as an energy source 14.1.2 Modeling, of biomass combustion 14.2 Simulation in power plant design and operation 14.2.1 Simulation tools 14.2.2 Simulator requirements _ 14.3 Biomass as a fuel 14.4 Biomass-fired power plants . , 14.4.1 Grate combustion 14.4.2 Fluidized bed combustion 14.4.2.1 Bubbling fluidized bed combustion . 14.4.2.2 Circulating fluidized bed combustion 14.5 Modelling of biomass combustion 14.5.1 Thermodynamic properties 14.5.1.1 Thermal conductivity 14.5.1.2 Specific heat ' ^ 14.5.1.3 Heat of formation ' 14.5.1.4 Heat of reaction . 14.5.1.5 Ignition temperature 14.5.2 Combustion process 14.5.2.1 Drying and ignition 14.5.2.2 Pyrolysis and combustion of volatile components 14.5.2.3 Combustion of remaining charcoal 14.6 Conclusions 14.7 Questions for discussions Optimal use of bioenergy by advanced modeling and control Bernt Lie & Erik Dahlquist 15.1 Current and future work in bioenergy system automation 15.2 Overview of processes 15.2.1 ' Biomass . ' " 15.2.2 Thermochemical processes -15.2.3 Biochemical processes 15.2.3.1 Fermentation 15.2.3.2 Anaerobic digestion 15.2.3.3 Biochemical processing 15.2.4 Characterization of processes 15.3 Process information 15.3.1 Sensors and instrumentation 15.3.2 Modeling and process description 15.3.2.1 Mechanistic models * 15.3.2.2 Models and model error 15.3.2.3 Empirical models „ 15.3.2.4 Model building and model simulation 15.3.3 Monitoring and fault detection 15.4 Process operation 15.4.1 Control and maintenance 15.4.2 Management and integration into product grids 15.5 Diagnostics and control using on-line physical simulation models 15.5.1 Introduction 15.5.2 Approach description .

357 357 357 358 358 359 359 360 361 361 363 364 365 365 365 365 366 366 366 366 366 367 368 368 369 370 373

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373 375 375 376 378 379 379 380 381 • 381 381 383, 384 385 386 386 387 387 387 ,389 390 390 391

xxx Table of contents

15.5.3 Boiler 15.5.4 Other energy conversion processes 15.5.5 Model validation and results 15.5.6 Discussion 15.6 Conclusions and questions for discussion 16.

Energy and exergy analyses of power generation systems using biomass and coal co-firing ~ Marc A. Rosen, Bale V Reddy & Shoaib Mehmood 16.1 Introduction 16.2 Background 16.2.1 Co-firirig and its advantages 16.2.2 Global status of co-firing 16.2.3 Properties of biomass and coal 16.2.4 technology options for co-firing 16.2.4.1 Direct co-firing * 16.2.4.2 Parallel co-firing 16.2.4.3 Indirect co-firing 16.3 Relevant studies on co-firing 16.3.1 Co-firing studies 16.3.2 Experimental studies 16.3.3 Modeling and simulation studies 16.3.4 Energy and exergy analyses 16.3.5 Economic studies 16.4 Characterstics of biomass fuels and coals 16.5 Co-firing system configurations 16.6 Thermodynamic modeling, simulation and analysis of co-firing systems 16.6.1 Approach and methodology 16.6.2 Assumptions and data 16.6.3 Governing equations 16.6.3:1 Analysis of boiler 16.6.3.2 Analysis of high pressure turbine _ 16.6.3.3 Analysis of low pressure turbine _ 16.6.3.4 Analysis of condenser , 16.6.3.5 Analysis of condensate pump 16.6.3.6 Analysis of boiler feedpump 16.6.3.7 Analysis of open feed water heater 16.6.4 Boiler and overall energy and exergy efficiencies 16.7 Effect of biomass co-firing on coal power generation systems 16.7.1 Effect of co-firing on overall system performance 16.7.2 Effect of co-firing on energy and exergy losses 16.7.2.1 . Effect of co-firing on furnace exit gas temperature 16.7.2.2 Effect of co-firing on energy losses and external exergy losses 16.7.2.3 Effect of co-firing on irreversibilities 16.7.3 Effect of co-firing on efficiencies 16.7.3.1 Boiler energy efficiency 16.7.3.2 Plant energy efficiency 16.7.3.3 Boiler exergy efficiency 16.7.3.4 Plant exergy efficiency 16.7.4 Effect of co-firing on emissions 16.7.4.1 Energy-based C02 emission factors

391 393 394 394 395

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16.8 16.9 17.

16.7.4.2 Energy-based NO* emission factors 16.7.4.3 Energy-based SO^ emission factors Conclusions Questions for discussions

Control of bioconversion processes K.P. Madhavan & Sharad Bhartiya 17.1 Introduction 17.2 Process dynamics 17.2.1 Physico-chemical models 17.2.1.1 Single vessel continuous digester for wood pulping 17.2.1.2 A physico-chemical model for the pulp digester 17.3 Approximate models to'capture essential dynamics 17.3.1 Single capacity element: first order system 17.3.2 Second order system 17.3.3 Dynamics of higher order processes 17.3.4 Pure time delay processes ' 17.3.5 Control relevant models for process control systems design 17.3.6 Linear system identification: single-vessel digester case study 17.3.7 Discrete-time models for sampled data system " . 17.3.8 Discrete-time models for nonlinear processes 17.4 Basic strategies for control , 17.4.1 Single feedback loop control 17.4.2 Internal model control structure 17.4.3 PI control of lower heater Kappa and blowline Kappa number 17.4.4 Single-loop control with disturbance compensation 17.4.4.1 Input disturbances: cascade control 17.4.4.2 Output disturbances: feedforward-feedback control 17.4.5 Feedback control with time delay compensation: the Smith predictor 17.4.6 Single loop control with nonlinear compensation 17.5 Uiiit-wide or multivariable control 17.5.1 Decentralized approach 17.5.1.1 Measures of multivariable interaction: relative gain array (RGA) V V 17.5.1.2 Interaction analysis for the single'vessel digester 17.6 Multiple single loop control using interaction compensators: Decoupler design 17.6.1 Decoupler design for single vessel digester 17.7 Model predictive control: A multivariable control strategy 17.7.1 Linear model predictive control for the single vessel digester 17.7.2 Control results and discussion 17.8 Realtime optimization 17.9 Concluding remarks 17.10 Questions for discussion

Subject index

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