Thermochemical Conversion of Biomass for the Production of Energy and Chemicals

This book highlights the processes of biomass thermochemical conversion, covering topics from combustion and gasification, to pyrolysis and liquefaction. Heat, power, biofuels and green chemicals can all be produced by these thermochemical processes. The different scales of investigation are presented: from the bioenergy chains, to the reactors and molecular mechanisms. The author uses current research and data to present bioenergy chains from forest to final use, including the biomass supply chains, as well as the life cycle assessment of different process chains. Biomass conversion reactors are also presented, detailing their technologies for combustion, gasification and syngas up-grading systems, pyrolysis and bio-oil upgrading. The physical-chemical mechanisms occurring in all these reactors are presented highlighting the main pathways for gas, char and bio-oil formation from biomass. This book offers an overview of biomass valorization for students, engineers or developers in chemistry, chemical, environmental or mechanical engineering.

Acknowledgments ix Introduction xi Chapter 1 Bioenergy Chain and Process Scales 1 1.1 Biomass production and ecological issues 1 1.2 Modeling of bioenergy chains 3 1.3 Technical-economical analysis of bioenergy chains 15 1.4 Life-cycle and multicriteria of bioenergy chains 20 Chapter 2 Reactor Scale 29 2.1 Introduction about the reactions occurring in biomass thermochemical reactors 29 2.2 Reactors for biomass combustion 32 2.3 Reactors for biomass gasification 38 2.4 Reactors for biomass pyrolysis 51 2.5 Reactors for biomass liquefaction 62 Chapter 3 Particle Scale and Mesoscale 67 3.1 Introduction on the main mechanisms occurring during wood pyrolysis 67 3.2 Physical-chemical mechanism of pyrolysis at the particle scale 68 3.3 Evolution of polymer network in biomass at the mesoscale 78 3.4 Structure of a char particle and mechanisms of its oxidation 89 Chapter 4 Molecular Scale 93 4.1 Introduction on the variability of biomass composition and the decoupling of reactions 93 4.2 Chemical structure of lignocellulosic biomass 94 4.3 Chemical mechanisms of primary pyrolysis 96 4.4 Molecular mechanisms of gas-phase reactions 109 4.5 Molecular mechanisms of catalytic reactions 117 Conclusion 135 Bibliography 139 Index 157