Production of biochar (the carbon (C)-rich solid formed by pyrolysis of biomass) and its storage in soils have been suggested as a means of abating climate change by sequestering carbon, while simultaneously providing energy and increasing crop yields. Substantial uncertainties exist, however, regarding the impact, capacity and sustainability of biochar at the global level. In this paper we estimate the maximum sustainable technical potential of biochar to mitigate climate change. Annual net emissions of carbon dioxide (CO 2 ), methane and nitrous oxide could be reduced by a maximum of 1.8 Pg CO 2 -C equivalent (CO 2 -C e ) per year (12 % of current anthropogenic CO 2 -C e emissions; 1 Pg = 1 Gt), and total net emissions over the course of a century by 130 Pg CO 2 -C e , without endangering food security, habitat or soil conservation. Biochar has a larger climate-change mitigation potential than combustion of the same sustainably procured biomass for bioenergy, except when fertile soils are amended while coal is the fuel being offset.

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Sustainable biochar to mitigate global climate change

An overview of the chemical composition of biomass

Entropy generation minimization (finite time thermodynamics, or thermodynamic optimization) is the method that combines into simple models the most basic concepts of heat transfer, fluid mechanics, and thermodynamics. These simple models are used in the optimization of real (irreversible) devices and processes, subject to finite‐size and finite‐time constraints. The review traces the development and adoption of the method in several sectors of mainstream thermal engineering and science: cryogenics, heat transfer, education, storage systems, solar power plants, nuclear and fossil power plants, and refrigerators. Emphasis is placed on the fundamental and technological importance of the optimization method and its results, the pedagogical merits of the method, and the chronological development of the field.

Entropy generation minimization: The new thermodynamics of finite-size devices and finite-time processes

Combustion characteristics of different biomass fuels

The carbonization of biomass residuals to char has strong potential to become an environmentally sound conversion process for the production of a wide variety of products. In addition to its traditional use for the production of charcoal and other energy vectors, pyrolysis can produce products for environmental, catalytic, electronic and agricultural applications. As an alternative to dry pyrolysis, the wet pyrolysis process, also known as hydrothermal carbonization, opens up the field of potential feedstocks for char production to a range of nontraditional renewable and plentiful wet agricultural residues and municipal wastes. Its chemistry offers huge potential to influence product characteristics on demand, and produce designer carbon materials. Future uses of these hydrochars may range from innovative materials to soil amelioration, nutrient conservation via intelligent waste stream management and the increase of carbon stock in degraded soils.

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Hydrothermal carbonization of biomass residuals: a comparative review of the chemistry, processes and applications of wet and dry pyrolysis

http://www-personal.umich.edu/~mswool/publications/cofire_prog_official_reprint.pdf

Co-firing of coal and biomass fuel blends

An experimental study on the effect of ultrasonication on viscosity and heat transfer performance of multi-wall carbon nanotube-based aqueous nanofluids

Introduction and Review of Thermodynamics Introduction Combustion Terminology Matter and Its Properties Microscopic Overview of Thermodynamics Conservation of Mass and Energy and the First Law of Thermodynamics The Second Law of Thermodynamics Summary Stoichiometry and Thermochemistry of Reacting Systems Introduction Overall Reactions Gas Analyses Global Conservation Equations for Reacting Systems Thermochemistry Summary Appendix Reaction Direction and Equilibrium Introduction Reaction Direction and Chemical Equilibrium Chemical Equilibrium Relations Vant Hoff Equation Adiabatic Flame Temperature with Chemical Equilibrium Gibbs Minimization Method Summary Appendix Fuels Introduction Gaseous Fuels Liquid Fuels Solid Fuels Other Fuels Size Distributions of Liquid and Solid Fuels Summary Appendix Chemical Kinetics Introduction Reaction Rates: Closed and Open Systems Elementary Reactions and Molecularity Multiple Reaction Types Chain Reactions and Reaction Mechanisms Global Mechanisms for Reactions Reaction Rate Theory and the Arrhenius Law Second Law and Global and Backward Reactions The Partial Equilibrium and Reaction Rate Expression Timescales for Reaction Solid-Gas (Heterogeneous) Reactions and Pyrolysis of Solid Fuels Summary Appendix Mass Transfer Introduction Heat Transfer and the Fourier Law Mass Transfer and Fick's Law Molecular Theory Generalized Form of Fourier's and Fick's Laws for a Mixture, with Simplifications Summary Appendix: Rigorous Derivation for Multicomponent Diffusion First Law Applications Introduction Generalized Relations in Molar Form Closed-System Combustion Open Systems Solid Carbon Combustion Droplet Burning Summary Conservation Relations Introduction Simple Diffusive Transport Constitutive Relations Conservation Equations Generalized Transport Simplified Boundary-Layer-Type Problems Shvab-Zeldovich Formulation Turbulent Flows Summary Appendix Combustion of Solid Fuels, Carbon, and Char Introduction Carbon Reactions Conservation Equations for a Spherical Particle Nondimensional Conservation Equations and Boundary Conditions Interfacial Conservation Equations or BCs Solutions for Carbon Particle Combustion Thermal NOx from Burning Carbon Particles Non-Quasi-Steady Nature of Combustion of Particle Element Conservation and Carbon Combustion Porous Char Summary Appendix: d Law and Stefan Flow Approximation Diffusion Flames - Liquid Fuels Introduction Evaporation, Combustion, and d2 Law Model/Physical Processes Governing Equations Solutions Convection Effects Transient and Steady-Combustion Results Multicomponent-Isolated-Drop Evaporation and Combustion Summary Combustion in Boundary Layers Introduction Phenomenological Analyses Generalized Conservation Equations and Boundary Conditions Interface Boundary Conditions Generalized Numerical Solution Procedure for BL Equations in Partial Differential Form Normalized Variables and Conservation Equations Similarity Solutions-BL Equations Applications of Generalized Similarity Equations to Various Flow Systems Solutions for Boundary Layer Combustion of Totally Gasifying Fuels Combustion Results for Fuels Burning under Convection Excess Fuel and Excess Air under Convection Summary Combustion of Gas Jets Introduction Burke-Schumann (B-S) Flame Modification to B-S Analyses Laminar Jets Planar Laminar Jets Circular Jets Summary of Solutions for 2-D and Circular Jets Stoichiometric Contours for 2-D and Circular Jets, Liftoff, and Blow-Off Jets in Coflowing Air: Jet Flame Structure in Strongly Coflowing Air for 2-D and Circular Jets Turbulent Diffusion Flames Partially Premixed Flame Summary Ignition and Extinction Introduction Modes of Ignition Ignition of Gas Mixtures in Rigid Systems: Uniform System Constant-Pressure Systems Ignition of Solid Particle Ignition of Nonuniform Temperature Systems-Steady-State Solutions Summary Deflagration and Detonation Introduction Conservation Equations Solutions for Rayleigh and Hugoniot Curves Flame Propagation into Unburned Mixture Summary Appendices Flame Propagation and Flammability Limits Introduction Phemenological Analysis Rigorous Analysis Flame Stretching Determination of Flame Velocity Flammability Limits Quenching Diameter Minimum Ignition Energy for Spark Ignition Stability of Flame in a Premixed Gas Burner Turbulent Flame Propagation Summary Interactive Evaporation and Combustion Introduction Simplified Analyses Arrays and Point Source Method Combustion of Clouds of Drops and Carbon Particles Terminology Governing Equations for Spherical Cloud Results Relation between Group Combustion and Drop Array Studies Interactive Char/Carbon Combustion Multicomponent Array Evaporation Summary Pollutants Formation and Destruction Introduction Emission-Level Expressions and Reporting Effects of Pollutants on Environment and Biological Systems Pollution Regulations NOx Sources and Production Mechanisms NOx Formation Parameters Stationary Source NOx Control CO2 Sequestration Carbon Monoxide: CO SOx Formation and Destruction Soot Mercury Emissions Summary An Introduction to Turbulent Combustion Introduction Turbulence Characteristics Averaging Techniques Instantaneous and Average Governing Equations Governing Differential Equations: Axisymmetric Case and Mixture-Fraction PDF Combustion Model Turbulent Combustion Modeling (Diffusion Flames) Probability Density Function Premixed and Partially Premixed Turbulent Flames: Modeling Approaches Summary Appendix I: Cylindrical Coordinate System with Particle-Laden Flow Problems Formulae Appendix A Appendix B References Index

Combustion Science and Engineering

Interactive processes in gasification and combustion. Part I: Liquid drop arrays and clouds

Thermolab Excel-Based Software for Thermodynamic Properties and Flame Temperatures of Fuels Introduction Importance, Significance and Limitations Review of Thermodynamics Mathematical Background Overview of Microscopic/Nanothermodynamics Summary Appendix: Stokes and Gauss Theorems First Law of Thermodynamics Zeroth Law First Law for a Closed System Quasi Equilibrium (QE) and Nonquasi-equilibrium (NQE) Processes Enthalpy and First Law Adiabatic Reversible Process for Ideal Gas with Constant Specific Heats First Law for an Open System Applications of First Law for an Open System Integral and Differential Forms of Conservation Equations Second Law of Thermodynamics and Entropy Thermal and Mechanical Energy Reservoirs Heat Engine and Heat Pump Consequences of the Second Law Entropy Entropy Balance Equation for a Closed System Irreversibility Entropy Measurements and Evaluation Local and Global Equilibrium Entropy: Energy Relation for Single Component Incompressible Fluids Third Law Entropy Balance Equation for an Open System Internally Reversible Work for an Open System Irreversible Processes and Efficiencies Cyclic Processes Entropy Balance in Integral and Differential Form Maximum Entropy and Minimum Energy Generalized Derivation of Equilibrium for a Single Phase Multiphase Multicomponent Equilibrium Availability Optimum Work and Irreversibility in a Closed System Availability or Exergy Analyses for a Closed System Generalized Availability Analysis Availability/Exergetic Efficiency Chemical Availability Integral and Differential Forms of Availability Balance Postulatory (Gibbsian) Thermodynamics Classical Rationale for Postulatory Approach Simple Compressible Substance Legendre Transform Application of Legendre Transform Work Modes and Generalized State Relation Thermodynamic Postulates for Simple Systems Fundamental Equations in Thermodynamics State Relationships for Real Gases and Liquids Equations of State Virial Equations Clausius-I Equation of State VW Equation of State Redlich-Kwong Equation of State Other Two-Parameter Equations of State Compressibility Charts (Principle of Corresponding States) Boyle Temperature and Boyle Curves Deviation Function Three Parameter Equations of State Generalized Equation of State Empirical Equations of State State Equations for Liquids/Solids Thermodynamic Properties of Pure Fluids Ideal Gas Properties James Clark Maxwell, 1831-1879 Relations Generalized Relations Evaluation of Thermodynamic Properties Pitzer Effect Kesler Equation of State (KES) and Kesler Tables Fugacity Experiments to Measure (uo - u) Vapor/Liquid Equilibrium Curve Throttling Processes Development Of Thermodynamic Tables Thermodynamic Properties of Mixtures Generalized Relations and Partial and Mixture Molal Properties Useful Relations for Partial Molal Properties Ideal Gas Mixture Ideal Solution Fugacity Excess Property Osmotic Pressure Molal Properties Using the Equations of State Phase Equilibrium for a Mixture Miscible, Immiscible, and Partially Miscible Mixture Phase Equilibrium Simplified Criteria for Phase Equilibrium Pressure and Temperature Diagrams Dissolved Gases in Liquids Deviations from Raoult's Law Stability Criteria for an Isolated System Mathematical Criterion for Stability Application to Boiling and Condensation Entropy Generation during Irreversible Transformation Spinodal Curves Determination of Vapor Bubble and Drop Sizes Chemically Reacting Systems Chemical Reactions and Combustion Thermochemistry First Law Analyses for Chemically Reacting Systems Combustion Analyses in the Case of Nonideal Behavior Second Law Analysis of Chemically Reacting Systems Mass Conservation and Mole Balance Equations Overview on Energy Consumption and Combustion Reaction Direction and Chemical Equilibrium Reaction Direction and Chemical Equilibrium Criteria for Direction of Reaction for Fixed Mass System Chemical Equilibrium Relations Van't Hoff Equation Equilibrium for Multiple Reactions Adiabatic Flame Temperature with Chemical Equilibrium Gibbs Minimization Method Appendix: Equilibrium Constant for any Reaction in Terms of Equilibrium Constants of Elements Availability Analysis for Reacting Systems Entropy Generation through Chemical Reactions Availability Fuel Cells Fuel Availability IC Engines and Exergy Thermal Sciences and Biological Systems Biomass Processing Food and Nutrients Human Body Metabolism Thermochemistry of Metabolism in Biological Systems Heat Transfer Analysis from the Body Body Temperature and Warm and Cold Blooded Second Law and Entropy Generation in Biological Systems Entropy Generation Through Chemical Reactions Lifespan, Energy and Entropy Allometry Problems A Summary of Chapterwise Formulae Appendix A: Tables Appendix B: Charts

Kalyan Annamalai

Papers

Co-firing of coal and biomass fuel blends

An experimental study on the effect of ultrasonication on viscosity and heat transfer performance of multi-wall carbon nanotube-based aqueous nanofluids

Combustion Science and Engineering

Interactive processes in gasification and combustion. Part I: Liquid drop arrays and clouds

Advanced Thermodynamics Engineering