Pyrolysis modeling of biomass: study of reaction yields using a single-particle model

Pyrolysis has been essential in the context of renewable energies, offering an innovative approach for biomass and solid waste valorization. Therefore, mathematical models that can represent its phenomena are of fundamental importance in understanding the reaction progression and optimizing the process. In this sense, we sought to analyze the capability of single-particle models in representing the yields of pyrolysis reactions in fluidized beds. To describe the behavior and interaction between the phases, we utilized an Eulerian-Lagrangian CFD modeling approach, solving the continuity, momentum, energy, species, and turbulence equations using OpenFOAM. We adopted the multicomponent and multi-stage model to describe the kinetics of pyrolysis in three different types of biomass. The numerical results obtained for the yields of pyrolysis reactions using the proposed modeling approach showed good agreement with the experimental data reported in the literature. We observed a maximum discrepancy of 3% in the study of pure cellulose reaction, 5.14% in red oak, and 0.56% in sugarcane bagasse. Therefore, we concluded that the single-particle model accurately represents the yields of pyrolysis reactions, making it suitable for estimating yields and conversion rates, providing valuable insights into pyrolysis behavior, and aiding in developing projects and optimization studies.