One-dimensional model of solar thermal reactors for the co-production of hydrogen and carbon black from methane decomposition

• Published in: International journal of hydrogen energy Vol. 36; no. 1; pp. 189 - 202
• Main Authors: Patrianakos, Giorgos, Kostoglou, Margaritis, Konstandopoulos, Athanasios
• Format: Journal Article
• Language: English
• Published: Kidlington Elsevier Ltd 2011; Elsevier
• Subjects: Alternative fuels. Production and utilization; Applied sciences; Carbon black; Convection; Convection modes; Energy; Exact sciences and technology; Fuels; Heat transfer; Hydrogen; Mathematical models; Methane; Methane decomposition; Particle; Reactors; Seeds; Solar reactor; Particle; Model; Carbon black; Hydrogen; Solar reactor; Methane decomposition; Methane; Particle size; Thermal decomposition; Gas release; Pollutant emission; One dimensional model; Kinetics; Hydrogen production
• ISSN: 0360-3199; 1879-3487
• DOI: 10.1016/j.ijhydene.2010.09.061

The solar thermal decomposition of methane is a promising route for the large scale production of hydrogen and carbon black with zero CO 2 emissions, however careful control of the reactor is required to ensure product particles of specific sizes. A one-dimensional model employing a sectional method is developed to simulate the evolution of polydisperse fresh and seed particle populations in an indirectly heated solar reactor. The model accounts for the homogeneous nucleation of fresh particles, the heterogeneous growth of the fresh and seed particles, particle coagulation, and the growth of carbon on the walls of the reactor from heterogeneous reaction and particle deposition. The heat transport mechanisms modelled include wall–gas convection, wall–particle radiation exchange, particle–gas convection and heat release from chemical reaction. The model is validated in terms of methane conversion against a 10 kW experimental solar reactor and used to extract kinetic parameters for the homogeneous and heterogeneous reaction paths. The model shows promise as a quick and simple tool for the design and control of industrial scale solar reactors.