Kinetic Modeling of Solid, Liquid and Gas Biofuel Formation from Biomass Pyrolysis

Debiagi, Paulo; Faravelli, Tiziano; Hasse, Christian; Ranzi, E.

doi:10.1007/978-981-15-2732-6_2

Cited by 6 publications

(5 citation statements)

References 140 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…The multistep pyrolytic reaction model is used in this study to simulate hardwood types of biomaterials. A more sophisticated kinetics model is available in the literature in which different types of biomass (i.e., hardwood, softwood, and grass) are handled separately, but different particle shrinkage mechanisms will be required. Figure shows the reaction pathways of three competing products: syngas, tar, and char, based on the Arrhenius reaction rate ( k i = A i e − E i / RT ) .…”

Section: Methodsmentioning

confidence: 99%

Modeling Biomass Particle Evolution at Pyrolysis Conditions Considering Shrinkage and Chemical Kinetics with Conjugate Heat Transfer

Cho

Kong

2023

Energy Fuels

View full text Add to dashboard Cite

Biomass pyrolysis is an attractive method to produce renewable biofuel in a short time scale. This paper discusses a computational study considering particle shrinkage and reaction kinetics to characterize biomass particle evolution under pyrolysis conditions. A representative elementary volume (REV) scale simulation was conducted in three dimensions to resolve the gas and solid domains. The interface was modeled using the conjugated heat transfer (CHT) and the adapted partially saturated method (PSM) in the lattice Boltzmann (LB) framework. A sufficient gas thickness was considered to simulate the interface physics, such as the thermal boundary layer and product gas outflux. The current simulation was validated using three different experiments. The particle conversion time, temperature, and shrinkage were well predicted. A parametric study investigated the effect of different modeling approaches and operating conditions. Results show that the internal heat transfer is affected by the particle size, inlet gas velocity, reactor temperature, and geometry. The Fourier number decreases to a nearly constant value as the particle size increases. The Péclet number increases linearly with the reactor temperature. Sub-particle scale simulation results reveal that the CHT model and permeability need to be considered when simulating gaseous product efflux out of the biomass particle. Three regimes are identified based on the particle permeability: diffusion-limited, mixed, and advection-limited. The gaseous product efflux delays the overall conversion in the mixed regime. A modified heat transfer coefficient is formulated based on the current numerical study.

show abstract

Section: Methodsmentioning

confidence: 99%

Modeling Biomass Particle Evolution at Pyrolysis Conditions Considering Shrinkage and Chemical Kinetics with Conjugate Heat Transfer

Cho

Kong

2023

Energy Fuels

View full text Add to dashboard Cite

show abstract

“…The kinetics include 32 chemical reactions, 29 solid species, and 29 gas species. The multistep multicomponent kinetics treat the biomass pyrolysis as a combination of the decomposition of cellulose (CELL; reactions 1-4), hemicellulose (GMSW, XYHW, XYGR; reactions 5-10), lignin (LIG-C, LIG-O, LIG-H; reactions 11-18), and extractives (TANN, TGL; reactions [19][20][21]. The mass fractions of cellulose, hemicellulose, lignin, extractives, moisture, and ash in the biomass particles are required as inputs to the kinetics, and these are usually obtained by experimental measurement or estimation using a characterization procedure that requires only the ultimate analysis [12].…”

Section: Detailed Pyrolysis Kinetic Mechanismmentioning

confidence: 99%

“…Lumped kinetics models are much simpler than the mechanistic models, where similar species are lumped together as a pseudo species, which is suitable for coupling with the reactor-scale model. In recent years, some detailed lumped biomass kinetic mechanisms with tens of reactions and species were developed [13,[18][19][20], which are more general than the extremely simplified one-step or twosteps kinetics and provides some flexibilities for modeling different kinds of biomass feedstocks.…”

Section: Introductionmentioning

confidence: 99%

Assessment of a detailed biomass pyrolysis kinetic scheme in multiscale simulations of a single-particle pyrolyzer and a pilot-scale entrained flow pyrolyzer

Gao

Shahnam

et al. 2021

Chemical Engineering Journal

View full text Add to dashboard Cite

“…As literature data are seldom complete, the missing information of biochars is obtained modeling the pyrolysis of the virgin biomass. In the present work, the kinetic model proposed by Debiagi et al was employed to evaluate the dry and ash-free elemental composition. If the elemental or biochemical composition of the virgin biomass are not available, data on the average composition of the same family of biomasses is employed (the Phyllis database may be used for this purpose).…”

Section: Model Validationmentioning

confidence: 99%

“…Several models were proposed in the literature to describe the many facets of this problem. The large majority focused on the investigation of the pyrolysis step, proposing empirical or semi-empirical chemical reaction mechanisms which usually have a limited range of applications. − Other authors accomplished important improvements toward multi-component − and mechanistic pyrolysis models. , The available literature still lacks a comprehensive approach to describe the char conversion step, encompassing fuels that exhibit widely different physical and chemical characteristics. Studies on coal chars are broadly available, including a variety of experimental and modeling activities, but a comprehensive model is still missing.…”

Section: Introductionmentioning

confidence: 99%

A Predictive Physico-chemical Model of Biochar Oxidation

et al. 2021

View full text Add to dashboard Cite

Pyrolysis of solid fuels forms a solid carbon-rich fuel, also called char, whose physico-chemical description is rather complex. Heterogeneous oxidation reactions take place during thermochemical conversion of char. The present work proposes a predictive detailed kinetic model, opening a new path for a deeper understanding of the char conversion process. This model considers porosity, surface area, density of surface sites, and their evolution along the conversion process. The chemical aspects of char oxidation are modeled assuming a carbonaceous bulk structure, surrounded by a variety of surface sites which represent the chemical functionalities typically present in such materials. The heterogeneous chemical reactions and their kinetic parameters are defined based on previous studies in the literature and by analogy to homogeneous gas-phase reactions of aromatic species. A mathematical framework is proposed to couple physical and chemical descriptions of the oxidation process. Although the proposed model benefits from experimental information, it is able to comprehensively describe the conversion rate of a broad range of carbonaceous materials such as carbon nanotubes, graphite, and chars only on the basis of their elemental composition. The proposed model represents a first step in exploring the explicit and coupled treatment given to the physical and chemical evolution of the fuel throughout its conversion, allowing us to consistently describe the particle evolution, opening a path for reliable models to manage the chemistry of char conversion.

show abstract

Kinetic Modeling of Solid, Liquid and Gas Biofuel Formation from Biomass Pyrolysis

Cited by 6 publications

References 140 publications

Modeling Biomass Particle Evolution at Pyrolysis Conditions Considering Shrinkage and Chemical Kinetics with Conjugate Heat Transfer

Modeling Biomass Particle Evolution at Pyrolysis Conditions Considering Shrinkage and Chemical Kinetics with Conjugate Heat Transfer

Assessment of a detailed biomass pyrolysis kinetic scheme in multiscale simulations of a single-particle pyrolyzer and a pilot-scale entrained flow pyrolyzer

A Predictive Physico-chemical Model of Biochar Oxidation

Contact Info

Product

Resources

About